Estimation of the Incidence of Late Bladder and Rectum Complications After High-Dose (70–78 Gy) Conformal Radiotherapy for Prostate Cancer,Using Dose–Volume Histograms

Purpose: To investigate whether Dose–Volume Histogram (DVH) parameters can be used to identify risk groups for developing late gastrointestinal (GI) and genitourinary (GU) complications after conformal radiotherapy for prostate cancer.Methods and Materials: DVH parameters were analyzed for 130 patients with localized prostate cancer, treated with conformal radiotherapy in a dose-escalating protocol (70–78 Gy, 2 Gy per fraction). The incidence of late (>6 months) GI and GU complications was classified using the RTOG/EORTC and the SOMA/LENT scoring system. In addition, GI complications were divided in nonsevere and severe (requiring one or more laser treatments or blood transfusions) rectal bleeding. The median follow-up time was 24 months. We investigated whether rectal and bladder wall volumes, irradiated to various dose levels, correlated with the observed actuarial incidences of GI and GU complications, using volume as a continuous variable. Subsequently, for each dose level in the DVH, the rectal wall volumes were dichotomized using different volumes as cutoff levels. The impact of the total radiation dose, and the maximum radiation dose in the rectal and bladder wall was analyzed as well.Results: The actuarial incidence at 2 years for GI complications ≥Grade II was 14% (RTOG/EORTC) or 20% (SOMA/LENT); for GU complications ≥Grade III 8% (RTOG/EORTC) or 21% (SOMA/LENT). Neither for GI complications ≥Grade II (RTOG/EORTC or SOMA/LENT), nor for GU complications ≥Grade III (RTOG/EORTC or SOMA/LENT), was a significant correlation found between any of the DVH parameters and the actuarial incidence of complications. For severe rectal bleeding (actuarial incidence at 2 years 3%), four consecutive volume cutoff levels were found, which significantly discriminated between high and low risk. A trend was observed that a total radiation dose ≥ 74 Gy (or a maximum radiation dose in the rectal wall >75 Gy) resulted in a higher incidence of severe rectal bleeding (p = 0.07).Conclusions: These data show that dose escalation up to 78 Gy, using a conformal technique, is feasible. However, these data have also demonstrated that the incidence of severe late rectal bleeding is increased above certain dose–volume thresholds.     

Grading-system-dependent volume effects for late radiation-induced rectal toxicity after curative radiotherapy for prostate cancer

PURPOSE: To assess the association between the dose distributions in the rectum and late Radiation Therapy Oncology Group and the European Organisation for Research and Treatment of Cancer (RTOG/EORTC), Late Effects of Normal Tissue SOMA, and Common Terminology Criteria for Adverse Events (CTCAE) version 3.0 graded rectal toxicity among patients with prostate cancer treated with RT. METHODS AND MATERIALS: Included in the study were 124 patients who received three-dimensional conformal RT for prostate cancer to a total dose of 70 Gy in 2-Gy fractions. All patients completed questionnaires regarding rectum complaints before RT and during long-term follow-up. Late rectum Grade 2 or worse toxicity, according to RTOG/EORTC, LENT SOMA, and CTCAE v3.0 criteria, was analyzed in relation to rectal dose and volume parameters. RESULTS: Dose-volume thresholds (V40>or=65%, V50>or=55%, V65>or=45%, V70>or=20%, and a rectum volumeor=70 Gy (V70) was most predictive for late Grade 2 or worse rectal toxicity with each of the grading systems. The associations were strongest, however, with use of the LENT SOMA system. CONCLUSIONS: Volume effects for late radiation-induced rectal toxicity are present, but their clinical significance depends on the grading system used. This should be taken into account in the interpretation of studies reporting on radiation-induced rectal toxicity.     

Predictive value of linear-quadratic model in the treatment of cervical cancer using high-dose-rate brachytherapy

: To determine whether a dose-response relationship exists between the biologic effective dose (BED) at Point A and the bladder and rectum and the clinical outcomes in our experience with external beam radiotherapy (EBRT) and high-dose-rate brachytherapy in the treatment of cervical carcinoma.

: This was a retrospective study. A total of 49 patients with cervical cancer were treated with a combination of EBRT (median 45 Gy, range 41.4–50.4) and high-dose-rate brachytherapy (median 18 Gy; range 18–19, in two fractions). Twenty-three patients received concomitant cisplatin-based chemotherapy. The cumulative BEDs were calculated at Point A (BED10) and at bladder and rectal reference points (BED3) using the linear-quadratic equation. The BED10 values, after incorporating a time factor (BED10tf) in the formula, were also calculated.

: In patients treated with RT alone, the local failure rate was 10% (1 of 10) and 19% (3 of 16) in patients receiving a BED10 >89 Gy10 or <89 Gy10 to Point A, respectively (p = 0.2). The corresponding local failure rates were 20% (3 of 15) and 0% (0 of 8) in patients treated with concomitant chemotherapy (p = 0.3). In patients treated with RT alone, the local failure rate was 7.7% (1 of 13) and 23% (3 of 13) in patients with a BED10tf >64 Gy10 or <64 Gy10 (p = 0.1), respectively. The median BED3 values at the rectal and bladder point was 95.5 Gy3 and 103.6 Gy3, respectively. Only 1 case of Grade 2 late rectal toxicity (2%) and no late bladder toxicity occurred.

: In patients treated with RT alone, a BED10 >89 Gy and a BED10tf >64 Gy indicated a trend toward a better local control rate. This difference was not observed in patients receiving chemotherapy. A BED3 <100 Gy3 was associated with negligible late toxicity. Although the BED10 in our study was about 10–15 Gy10 less than that in the published data, the 4-year local control rate of 80% and 83% and disease-free survival rate of 75% and 70% with and without chemotherapy, respectively, compare well with the rates in other studies in the literature.     

Effect of balloon occluded arterial infusion of anticancer drugs on the prognosis of cervical cancer treated with radiation therapy

: The effect of local injection of anticancer drugs by ballon catheter, i.e., balloon occuluded arterial infusion (BOAI), on the prognosis of cervical cancer treated with radiotherapy were retrospectively estimated.

: Sixty-five patients with cervical cancer (Stage I–IV) treated by irradiation were included in the study. Among the 65 cases, 2 were in Stage I, 13 in Stage II, 40 in Stage III, and 10 in Stage IV. Patients who received surgical resection were excluded. Thirty-nine patients received BOAI and 44 received brachytherapy. Twenty-six patients were not indicated for BOAI because of insufficient renal function, hepatic complications, hemotological complications, and refusal from the patients. Cisplatin (0.9–1.7 mg/kg), Adriamycin (0.7–0.9 mg/kg), and Pepleomycin (0.4–0.6 mg/kg) were administered simultaneously into the bilateral internal iliac arteries by BOAI. External irradiation was given by 10 MV x-ray. Total dose administered to the regional lymph nodes by the external irradiation was 48.3 ± 8.7 Gy. Radium was used at brachytherapy. The dose delivered by the brachytherapy at point A was 45.3 ± 14.9 Gy. Patients without brachytherapy received 26.1 ± 19.1 Gy of boost irradiation by the external photon beam. The survival probabilities of the patients were calculated by Kaplan-Meier method.

: The 5-year survival rates of the Stage III patients with and without BOAI were 53 ± 13% and 24 ± 18%, respectively (p = 0.036). By multivariate analyses using Cox's proportional hazard model, stage and BOAI were selected as significant predictors of the prognosis. Transient bone marrow suppression was observed in about half of the patients with BOAI. No significant increase of the incidence of the late radiation damage by BOAI in rectum or in urinary bladder was observed.

: Balloon occuluded arterial infusion of anticancer drugs may improve the prognosis of the patients with cervical cancer without increasing the incidence of the late radiation damage. A larger scale prospective randomized study is desired.     

Late toxicity results of the GORTEC 94-01 randomized trial comparing radiotherapy with concomitant radiochemotherapy for advanced-stage oropharynx carcinoma: comparison of LENT/SOMA,RTOG/EORTC,and NCI-CTC scoring systems

PURPOSE: To prospectively assess 5-year late toxicity in patients treated by concomitant radiochemotherapy for locally advanced oropharynx carcinoma using three different toxicity scales. METHODS AND MATERIALS: A total of 226 patients were entered in a Phase III multicenter, randomized trial comparing radiotherapy alone (70 Gy in 35 fractions: Arm A) with concomitant radiochemotherapy (70 Gy in 35 fractions with three cycles of a 4-day regimen containing carboplatin and 5-fluorouracil: Arm B). Five living patients, free of local or distant recurrences, could not be evaluated for late toxicity. Forty-four patients were eligible for late toxicity with a median follow-up of 5 years. Late toxicity was evaluated by the radiation oncologist using a large questionnaire containing 120 mixed items of three scales (NCI-CTC, LENT/SOMA, and RTOG). The data were then transposed on separate scales using corresponding grades. RESULTS: The 5-year overall survival rate was 22% in Arm B and 16% in Arm A (p = 0.05). The 5-year locoregional control rate was 48% in Arm B and 25% in Arm A (p = 0.002). The spinal cord was not affected by the concomitant adjunct of chemotherapy, and no deaths were caused by late toxicity. Using the three late toxicity scales, 100% of the patients treated with the combined modality (Arm B) developed one or more late complications vs. 94% in the radiotherapy-alone arm (Arm A). The difference was not statistically significant. The most commonly damaged organs (all Grade 1-4) were the salivary glands (100% in Arm B vs. 82% in Arm A, p <0.05), skin (78% vs. 47%, p <0.05), teeth (67% vs. 18%, p <0.05), mucosa (59% vs. 63% p = not significant), and mandible (44% vs. 12%, p <0.05). One or more Grade 3-4 complications occurred in 82% of the patients in Arm B vs. 47% in Arm A (p = 0.02) but concerned only the teeth. The correlation between the RTOG and LENT/SOMA scale and between the NCI-CTC and LENT/SOMA scale were low for Grade 1-4 toxicity (near 30%). The transposability of a patient's symptoms was significantly greater using the LENT/SOMA or RTOG/EORTC scaling systems than using the NCI-CTC system. CONCLUSION: Concomitant radiochemotherapy increased overall survival and locoregional control rates. The difference between the two treatment groups for Grade 3-4 complications was only significant for the teeth. The late toxicity assessment of a treatment may depend on the toxicity scale used. The LENT/SOMA scale seems to be the most accurate scale, but most of the score results were not concordant with those obtained with other scales. The results of this study confirm the necessity of using a common late toxicity scale in clinical trials.     

Conformal technique dose escalation for prostate cancer: Biochemical evidence of improved cancer control with higher doses in patients with pretreatment prostate-specific antigen ≥10 ng/ml

: Conformal radiation technology results in fewer late complications and allows testing of the value of higher doses in prostate cancer.

: We report the biochemical freedom from disease (bNED) rates (BNED) failure in Prostate Specific Antigen (PSA) ≥ 1.5 ng/ml and rising) at 2 and 3 years for 375 consecutive patients treated with conformal technique from 66 to 79 Gy. Median follow-up was 21 months. Biochemical freedom from disease was analyzed for patients treated above and below 71 Gy as well as above and below 73 Gy. Each dose group was subdivided by pretreatment PSA level (<10, 10–19.9, and ≥20 ng/ml). Dose was stated to be at the center of prostate gland.

: There was significant improvement in bNED survuval for all patients divided by a dose above or below 71 Gy (p = 0.007) and a marginal improvement above or below 73 Gy (p = 0.07). Subdividing by pretreatment PSA level showed no benefit to the PSA < 10 ng/ml group at the higher dose but there was a significant improvement at 71 and 73 Gy for pretreatment PSA 10–19.9 ng/ml (p = 0.03 and 0.05, respectively) and for pretreatment PSA ≥ 20 ng/ml (p = 0.003 and 0.02, respectively).

: Increasing dose above 71 or 73 Gy did not result in improved bNED survuval for patient with pretreatment PSA < 10 ng/ml at 2 or 3 years. Further dose escalation studies may not be useful in the patients. A significant improvement in bNED survuval was noted for patients with pretreatment PSA ≥ 10 ng/ml treated above 71 of 73 Gy; further dose escalation studies are warranted.     

Medication for hearing loss after fractionated stereotactic radiotherapy (SRT) for vestibular schwannoma

To investigate the effectiveness of corticosteroid treatments for patients showing decreases in hearing levels after stereotactic radiotherapy for vestibular schwannoma.

Twenty-one patients experienced a hearing loss in pure-tone average at greater than 20 dB or less than 10 dB within 1 year after irradiation administration of 44 Gy/22 fractions followed by a 4 Gy boost. Eight received oral prednisone at a daily dose of 30 mg, which was gradually decreased (medicated group), and 13 received none (nonmedicated group). The average observation period was 26.7 ± 16.6 (range: 6–69) months.

Hearing recovery was seen after initial onset of the hearing loss in all 8 patients in the medicated group and in 2 of 13 patients in the nonmedicated group (p = 0.001). The hearing recovery, that is, the change in pure-tone average (dB) at the last follow-up from the onset of hearing loss, was 9.8 ± 6.9 dB (recovery) in the medicated group and −9.4 ± 12.8 dB (further loss) in the nonmedicated group (p = 0.0013). The hearing recovery rate, normalizing to the degree of the hearing loss before medication, was also significantly higher in the medicated group than in the nonmedicated group (p = 0.0014).

Corticosteroidal intake is suggested to be effective in improving hearing loss after stereotactic radiotherapy, at least in young patients having a useful pretreatment hearing level, if the treatment for hearing loss is administered immediately after the hearing loss is first detected.     

A phase III comparison of radiation therapy with or without recombinant β-interferon for poor-risk patients with locally advanced non-small-cell lung cancer (RTOG 93-04)

: The results of Phase I/II data testing β-interferon with radiation therapy in a non-small-cell lung cancer population were promising. Based on these data, the Radiation Therapy Oncology Group (RTOG) initiated a Phase III trial to test the efficacy of β-interferon in poor-risk patients with Stages IIIA and IIIB non-small-cell lung carcinoma.

: Between September 1994 and March 1998, 123 patients were accrued to this trial. Enrolled patients were not eligible for other chemoradiation studies within the RTOG. Eligibility criteria included histologically confirmed Stage IIIA or IIIB non-small-cell lung cancer (according to American Joint Committee on Cancer) considered clinically inoperable or unresectable at the time of surgery. Patients were required to have a Karnofsky performance status 50–70 or >70 and at least 5% weight loss over the preceding 3 months. Betaseron (recombinant human interferon beta_ser, rHuIFN-β_ser,) was the chosen preparation of β-interferon. The patients randomized to the investigational arm received 16 × 10⁶ IU of Betaseron by i.v. bolus given 3 days a week (Monday–Wednesday) on Weeks 1, 3, and 5. The Betaseron was given 30 minutes before radiation therapy for a total of nine doses. Irradiation was delivered at 2 Gy per fraction, 5 days a week, for a total of 60 Gy over 6 weeks and was identical for both arms. The primary end point of the trial was overall survival with local control as a secondary end point. Toxicities occurring within 90 days of therapy completion were defined as acute.

: The median follow-up was 4 years (range: 2.5–6 years) for surviving patients. Seventy-six percent of all patients completed β-interferon. Toxicity was the primary reason for noncompliance. Radiotherapy (RT) compliance was excellent in the RT-alone arm, with 94% completing therapy, compared to 82% in the β-interferon arm (p = 0.0475). Grade 3 and 4 acute toxicities were higher on the β-interferon arm (p = 0.0249). Grade 3 and 4 acute toxicities were primarily related to lung (n = 8) and esophagus (n = 7). No Grade 4 or 5 late toxicities were seen for patients in the radiation-alone arm. However, three patients on the β-interferon arm experienced Grade 4 toxicity, and one patient died. The 1-year survival rate for the RT-alone arm was 44% with a median survival time of 9.5 months. The 1-year survival on the β-interferon arm was 42% with a median survival of 10.3 months. There was no statistical difference in survival times (p = 0.66).

: This multicenter, controlled Phase III trial failed to confirm the efficacy of Betaseron in patients receiving definitive radiotherapy for locally advanced, nonmetastatic non-small-cell lung cancer. The use of β-interferon led to greater rates of both acute and late treatment-related toxicity. The RTOG continues to investigate other biologic modifiers that may provide a nontoxic alternative for this poor-risk population.     

Prostate cancer radiation dose response: results of the M. D. Anderson phase III randomized trial

A randomized radiotherapy dose escalation trial was undertaken between 1993 and 1998 to compare the efficacy of 70 vs. 78 Gy in controlling prostate cancer.

A total of 305 Stage T1–T3 patients were entered into the trial and, of these, 301 with a median follow-up of 60 months, were assessable. Of the 301 patients, 150 were in the 70 Gy arm and 151 were in the 78 Gy arm. The primary end point was freedom from failure (FFF), including biochemical failure, which was defined as 3 rises in the prostate-specific antigen (PSA) level. Kaplan-Meier survival analyses were calculated from the completion of radiotherapy. The log-rank test was used to compare the groups. Cox proportional hazard regression analysis was used to examine the independence of study randomization in multivariate analysis.

There was an even distribution of patients by randomization arm and stage, Gleason score, and pretreatment PSA level. The FFF rates for the 70- and 78 Gy arms at 6 years were 64% and 70%, respectively (p = 0.03). Dose escalation to 78 Gy preferentially benefited those with a pretreatment PSA >10 ng/mL; the FFF rate was 62% for the 78 Gy arm vs. 43% for those who received 70 Gy (p = 0.01). For patients with a pretreatment PSA ≤10 ng/mL, no significant dose response was found, with an average 6-year FFF rate of about 75%. Although no difference occurred in overall survival, the freedom from distant metastasis rate was higher for those with PSA levels >10 ng/mL who were treated to 78 Gy (98% vs. 88% at 6 years, p = 0.056). Rectal side effects were also significantly greater in the 78 Gy group. Grade 2 or higher toxicity rates at 6 years were 12% and 26% for the 70 Gy and 78 Gy arms, respectively (p = 0.001). Grade 2 or higher bladder complications were similar at 10%. For patients in the 78 Gy arm, Grade 2 or higher rectal toxicity correlated highly with the proportion of the rectum treated to >70 Gy.

An increase of 8 Gy resulted in a highly significant improvement in FFF for patients at intermediate-to-high risk, although the rectal reactions were also increased. Dose escalation techniques that limit the rectal volume that receives ≥70 Gy to <25% should be used.     

A phase III study of adjuvant chemotherapy in advanced nasopharyngeal carcinoma patients

To evaluate the role of adjuvant chemotherapy in locally advanced nasopharyngeal carcinoma (NPC) patients, we conducted a randomized Phase III trial comparing radiotherapy (RT) followed by adjuvant chemotherapy to RT alone in patients with advanced NPC.

Between November 1994 and March 1999, 157 patients with Stage IV, M₀ (UICC/AJCC, 1992) advanced NPC disease were randomized to receive standard radiotherapy, as follows: 35–40 fractions, 1.8–2.0 Gy/fraction/day, 5 days/week, to a total dose 70–72 Gy with or without 9 weekly cycles of 24-h infusional chemotherapy (20 mg/m² cisplatin, 2,200 mg/m² 5-fluorouracil, and 120 mg/m² leucovorin) after RT. Of 157 patients enrolled, 154 (77 radiotherapy, 77 combined therapy) were evaluable for survival and toxicity analysis.

With a median follow-up of 49.5 months, the 5-year overall survival and relapse-free survival rates were 60.5% vs. 54.5% (p = 0.5) and 49.5% vs. 54.4% (p = 0.38) for the radiotherapy-alone group and the combined radiotherapy and adjuvant chemotherapy group, respectively. The Cox regression showed that the hazard rates ratio of combined treatment to RT alone was 0.673 (p VALUE = 0.232); the 95% confidence interval was 0.352 and 1.288, respectively. Patients who received combined treatment had a lower systemic relapse rate than radiotherapy-alone patients, according to relapse pattern analysis. The incidence of leukopenia (≥ Grade 3) occurred in 17 out of 819 (2.1%) cycles of weekly chemotherapy. No patient developed moderate to severe mucositis (≥ Grade 3).

We conclude that adjuvant chemotherapy after RT for patients with advanced NPC has no benefit for overall survival or relapse-free survival.     

Increasing the rate of late toxicity by changing the score? A comparison of RTOG/EORTC and LENT/SOMA scores

PURPOSE: The Radiation Therapy Oncology Group (RTOG) and Late Effects Normal Tissue Task Force subjective, objective, management, and analytic (LENT/SOMA) scores were compared in a group of breast cancer patients. The impact of the classification system on grading late effects was evaluated. MATERIALS AND METHODS: Telangiectasia, skin pigmentation, and fibrosis were scored according to both LENT/SOMA and RTOG criteria. The results were compared with respect to up- or downgrading and correlated (Spearman's rho). Other side effects were recorded using LENT/SOMA criteria. Interobserver variability was calculated with Cohen's kappa. Two hundred fifty-nine subsequent relapse-free patients who underwent breast-conserving therapy between 1981 and 1995 were examined. The median dose of radiotherapy to the breast was 55 Gy. Adjuvant chemotherapy was given to 31 patients and tamoxifen to 52 patients. The median follow-up was 8 years. RTOG skin and s.c. tissue scales and LENT/SOMA breast and pigmentation scales were used. Two doctors examined 45 patients jointly. RESULTS: Of all patients, 20% had telangiectasia, 22% pigmentation, 43% fibrosis, 4% breast edema, 77% retraction/atrophy, and 54% pain. In comparison, when LENT/SOMA criteria were used, telangiectasia and pigmentation were upgraded in 34% and 36%, respectively, and telangiectasia was downgraded in 45%. Fibrosis correlated well (Spearman's rho 0.78, p = 0.01). An additional 356 side effects, mainly retraction/atrophy were observed in 226 patients using LENT/SOMA criteria. Interobserver variability was similar for both classification systems and ranged from Cohen's kappa 0.3 (retraction) to 0.91 (telangiectasia). CONCLUSIONS: LENT/SOMA criteria seem to be the better tool in grading and recording late radiation toxicity compared with the RTOG scale. There was some upgrading with the RTOG score when skin toxicity is evaluated. In contrast, fibrosis scores correlated very well. Adjustments of the LENT/SOMA scoring system should be considered to standardize reporting of late radiation morbidity.     

Late rectal toxicity: dose-volume effects of conformal radiotherapy for prostate cancer

: To identify dosimetric, anatomic, and clinical factors that correlate with late rectal toxicity after three-dimensional conformal radiotherapy (3D-CRT) for prostate cancer.

: We retrospectively analyzed the dose-volume histograms and clinical records of 163 Stage T1b-T3c prostate cancer patients treated between 1992 and 1999 with 3D-CRT, to a total isocenter dose of 74–78 Gy at The University of Texas M. D. Anderson Cancer Center. The median follow-up was 62 months (range 24–102). All late rectal complications were scored using modified Radiation Therapy Oncology Group and Late Effects Normal Tissue Task Force criteria. The 6-year toxicity rate was assessed using Kaplan-Meier analysis and the log-rank test. A univariate proportional hazards regression model was used to test the correlation between Grade 2 or higher toxicity and the dosimetric, anatomic, and clinical factors. In a multivariate regression model, clinical factors were added to the dosimetric and anatomic variables to determine whether they significantly altered the risk of developing late toxicity.

: At 6 years, the rate of developing Grade 2 or higher late rectal toxicity was 25%. A significant volume effect was observed at rectal doses of 60, 70, 75.6, and 78 Gy, and the risk of developing rectal complications increased exponentially as greater volumes were irradiated. Although the percentage of rectal volume treated correlated significantly with the incidence of rectal complications at all dose levels (p <0.0001 for all comparisons), the absolute rectal volume appeared to be a factor only at the higher doses of 70, 75.6, and 78 Gy (p = 0.0514, 0.0016, and 0.0021, respectively). The following variables also correlated with toxicity on the univariate analysis: maximal dose to the clinical target volume, maximal dose to rectum, maximal dose to the rectum as a percentage of the prescribed dose, and maximal dose delivered to 10 cm³ of the rectum. Of the clinical variables tested, only a history of hemorrhoids correlated with rectal toxicity (p = 0.003). Multivariate analysis showed that the addition of hemorrhoids increased the risk of toxicity for each dosimetric variable found to be significant on univariate analysis (p <0.05 for all comparisons).

: Dose-volume histogram analyses clearly indicated a volume effect on the probability of developing late rectal complications. Therefore, dose escalation may be safely achieved by adherence to dose-volume histogram constraints during treatment planning and organ localization at the time of treatment to ensure consistent patient setup.     

Local excision and postoperative radiotherapy for distal rectal cancer

To assess the outcome following local excision and postoperative radiotherapy (RT) for distal rectal carcinoma.

Seventy-three patients received postoperative radiotherapy following local surgery for primary rectal carcinoma at Princess Margaret Hospital from 1983 to 1998. Selection factors for postoperative RT were patient preference, poor operative risks, and “elective” where conservative therapy was regarded as optimal therapy. Median distance of the primary lesion from the anal verge was 4 cm (range, 1–8 cm). There were 24 T1, 36 T2, and 8 T3 lesions. The T category could not be determined in 5. Of 55 tumor specimens in which margins could be adequately assessed, they were positive in 18. RT was delivered using multiple fields by 6- to 25-MV photons. Median tumor dose was 50 Gy (range, 38–60 Gy), and 62 patients received 50 Gy in 2.5-Gy daily fractions. The tumor volume included the primary with 3–5 cm margins. No patients received adjuvant chemotherapy. Median follow-up was 48 months (range, 10–165 months).

Overall 5-year survival and disease-free survival were 67% and 55%, respectively. Tumor recurrence was observed in 23 patients. There were 14 isolated local relapses; 6 patients developed local and distant disease; and 3 relapsed distantly only. For patients with T1, T2, and T3 lesions, 5-year local relapse-free rates were 61%, 75%, and 78%, respectively, and 5-year survival rates were 76%, 58%, and 33%, respectively. The 5-year local relapse-free rate was lower in the presence of lymphovascular invasion (LVI) compared to no LVI, 52% vs. 89%, p = 0.03, or where tumor fragmentation occurred during local excision compared to no fragmentation, 51% vs. 76%, p = 0.02. Eleven of 14 patients with local relapse only underwent abdominoperineal resection, 8 achieved local control, and 4 remained cancer free. The ultimate local control, including salvage surgery, was 86% at 5 and 10 years. The 5-year colostomy-free rate was 82%. There were 2 patients who experienced RTOG Grade 3 late complications, and 1 with Grade 4 complication (bowel obstruction requiring surgery).

The local relapse rate for patients with T1 disease was high compared to other series of local excision and postoperative RT. Patients with LVI or tumor fragmentation during excision have high local relapse rates and may not be good candidates for conservative surgery and postoperative RT.     

Intensified hyperfractionated accelerated radiotherapy limits the additional benefit of simultaneous chemotherapy--results of a multicentric randomized German trial in advanced head-and-neck cancer

To demonstrate the efficacy of radiochemotherapy (RCT) as the first choice of treatment for advanced unresectable head-and-neck cancer. To prove an expected benefit of simultaneously given chemotherapy, a two-arm randomized study with hyperfractionated accelerated radiochemotherapy (HF-ACC-RCT) vs. hyperfractionated accelerated radiotherapy (HF-ACC-RT) was initiated. The primary endpoint was 1-year survival with local control (SLC).

Patients with Stage III and IV (UICC) unresectable oro- and hypopharyngeal carcinomas were randomized for HF-ACC-RCT with 2 cycles of 5-FU (600 mg/m²/day)/carboplatinum (70 mg/m²) on days 1–5 and 29–33 (arm A) or HF-ACC-RT alone (arm B). In both arms, there was a second randomization for testing the effect of prophylactically given G-CSF (263 μg, days 15–19) on mucosal toxicity. Total RT dose in both arms was 69.9 Gy in 38 days, with a concomitant boost regimen (weeks 1–3: 1.8 Gy/day, weeks 4 and 5: b.i.d. RT with 1.8 Gy/1.5 Gy). Between July 1995 and May 1999, 263 patients were randomized (median age 56 years; 96% Stage IV tumors, 4% Stage III tumors).

This analysis is based on 240 patients: 113 patients with RCT and 127 patients with RT, qualified for protocol and starting treatment. There were 178 oropharyngeal and 62 hypopharyngeal carcinomas. Treatment was tolerable in both arms, with a higher mucosal toxicity after RCT. Restaging showed comparable nonsignificant different CR + PR rates of 92.4% after RCT and 87.9% after RT (p = 0.29). After a median observed time of 22.3 months, l- and 2-year local-regional control (LRC) rates were 69% and 51% after RCT and 58% and 45% after RT (p = 0.14). There was a significantly better 1-year SLC after RCT (58%) compared with RT (44%, p = 0.05). Patients with oropharyngeal carcinomas showed significantly better SLC after RCT (60%) vs. RT (40%, p = 0.01); the smaller group of hypopharyngeal carcinomas had no statistical benefit of RCT (p = 0.84). For both tumor locations, prophylactically given G-CSF was a poor prognostic factor (Cox regression), and resulted in reduced LRC (log-rank test: ± G-CSF, p = 0.0072).

With accelerated radiotherapy, the efficiency of simultaneously given chemotherapy may be not as high as expected when compared to standard fractionated RT. Oropharyngeal carcinomas showed better LRC after HF-ACC-RCT vs. HF-ACC-RT; hypopharyngeal carcinomas did not. Prophylactic G-CSF resulted in an unexpected reduced local control and should be given in radiotherapy regimen only with strong hematologic indication.     

Serum PSA evaluations during salvage radiotherapy for post-prostatectomy biochemical failures as prognosticators for treatment outcomes

Serum prostate specific antigen (PSA) levels have proved to be sensitive markers for the diagnosis of prostate cancer. In addition, PSA levels are useful for detecting and monitoring prostate cancer progression after radiotherapy. Serum PSA evaluations during radiotherapy, however, have not been well documented. In this study, we investigate the prognostic value of PSA evaluations during salvage radiotherapy for prostatectomy failures.

Forty-one patients with biochemical failures after prostatectomy treated with salvage radiotherapy consented to have their serum PSA levels evaluated at 30 Gy and 45 Gy of irradiation. All 41 patients had negative metastatic workup and pathologically uninvolved pelvic lymph nodes at the time of referral for salvage radiotherapy. Radiation therapy was delivered with 10–25 MV photons, with doses of 59.4–66.6 Gy. No patients received hormonal ablation therapy before irradiation.

The mean follow-up for all patients was 30.9 months. At last follow-up, 28/41 patients (68.3%) were free from biochemical failure, with 20 of 41 patients (48.8%) expressing undetectable PSA levels. Serum PSA evaluations at 30 Gy did not significantly predict for either biochemical (p = 0.0917) or clinical (p = 0.106) disease-free outcome. However, serum PSA evaluations at 45 Gy significantly predicted for both biochemical (p = 0.0043) and clinical (p = 0.0244) disease-free outcomes, with PSA elevations at 45 Gy significantly associated with poor outcomes. On univariate analysis of prognosticators for biochemical failures, the following were significant: an elevation in serum PSA levels at 45 Gy, detectable serum PSA immediately after prostatectomy, Gleason score 7–10, and serum PSA level >1 ng/ml before salvage radiotherapy.

Evaluation of serum PSA level at 45 Gy of salvage radiotherapy for biochemical relapses after prostatectomy may serve as a significant prognosticator for both biochemical and clinical disease-free outcomes.     

Metastatic melanoma to the brain: prognostic factors after gamma knife radiosurgery

To identify important prognostic factors predictive of survival and tumor control in patients with metastatic melanoma to the brain who underwent gamma knife radiosurgery.

A total of 122 consecutive patients with 332 intracranial melanoma metastases underwent gamma knife radiosurgery over a 5-year period. Of these, 39 (32%) also received whole-brain irradiation (WBI). The median tumor volume was 0.8 cm³ (range: 0.02–30.20 cm³), and the median prescribed dose was 20 Gy (range: 14–24 Gy). Median follow-up was 6.8 months. Univariate and multivariate analyses of survival and freedom from progression were performed using the following parameters: status of systemic disease, intracranial tumor volume, number of lesions, tumor location, Karnofsky performance status, gender, age, and WBI.

Overall median survival was 7.0 months from time of radiosurgery and 9.1 months from the onset of brain metastasis. In multivariate analysis, improved survival was noted in patients with total intracranial tumor volume <3 cm³ (p = 0.003) and inactive systemic disease (p = 0.0065), whereas other parameters studied were of lesser importance (tumor location, p = 0.056, and Karnofsky performance status, p = 0.086), or of no significance (number of lesions, WBI, age, and gender). Freedom from subsequent brain metastasis depended on intracranial tumor volume (p = 0.0018) and status of systemic disease (p = 0.034).

Conclusions: Stereotactic radiosurgery is an effective treatment modality for patients with intracranial metastatic melanoma. Tumor volume and status of systemic disease are good independent predictors of survival and freedom from tumor progression.     

Dose optimization of fractionated external radiation and high-dose-rate intracavitary brachytherapy for FIGO stage IB uterine cervical carcinoma

: To determine the optimal dose combination scheme of external beam radiotherapy (EBRT) and high-dose-rate (HDR) intracavitary radiation (ICR) for maximizing tumor control while conferring an acceptable late complication rate in the treatment of Stage IB uterine cervical cancer.

: We retrospectively analyzed 162 patients with International Federation of Gynecology and Obstetrics (FIGO) Stage IB squamous cell carcinoma of the uterine cervix who received definitive RT between May 1979 and December 1990. Before HDR-ICR, all patients received EBRT to a total dose of 40–46 Gy (median 45), administered during 4–5 weeks to the whole pelvis. HDR-ICR was given 3 times weeks to a total dose of 24–51 Gy (median 39) at point A, using a dose of 3 Gy/fraction. Central shielding from EBRT was begun after the delivery using 20–45 Gy (median 40) of the external dose. The total dose to point A, calculated by adding the EBRT biologically effective dose (BED) and the ICR BED to point A, was 74.1–118.1 Gy (mean 95.2). The rectal point dose was calculated at the anterior rectal wall at the level of the cervical os. The local control rate, survival rate, and late complication rate were analyzed according to the irradiation dose and BED.

: The initial complete response rate was 99.4%. The overall 5-year survival rate and 5-year disease-free survival rate was 91.1% and 90.9%, respectively. The local failure rate was 4.9%, and the distant failure rate was 4.3%. Late complications were mild and occurred in 23.5% of patients, with 18.5% presenting with rectal complications and 4.9% with bladder complications. The mean rectal BED (the sum of the external midline BED and the ICR rectal point BED) was lower in the patients without rectal complications than in those with rectal complications (125.6 Gy vs. 142.7 Gy, p = 0.3210). The late rectal complication rate increased when the sum of the external midline BED and the rectal BED by ICR was ≥131 Gy (p = 0.1962). However, 5-year survival rates did not increase with the external midline BED (p = 0.4093). The late rectal complication rate also increased, without a change in the survival rate, when the sum of the external midline BED and the ICR point A BED was >90 Gy.

: In treating Stage IB carcinoma of the uterine cervix with HDR-ICR, using fractions of 3 Gy, it is crucial to keep the point A BED at ≤90 Gy to minimize late rectal complications without compromising the survival rate. To achieve this goal, appropriate central shielding from EBRT is needed.     

Cumulative interfraction interval analysis of influence of time and interruptions on radiotherapy results in oral cancers

To present a new approach to analyze the influence of time and interruptions in fractionated radiotherapy, in terms of cumulative interfraction intervals (CIFIs), that is, the interval between nonsuccessive fractions of radiotherapy.

The subjects were 142 patients with epidermoid cancer of the buccal mucosa-gingiva-palate region treated by 60 Gy in 25 fractions during 5 weeks. The influence of CIFI between the first and sixth, eleventh, sixteenth, and twenty-first fractions (CIFI_1–6, CIFI_1–11, CIFI_1–16, and CIFI_1–21, respectively), as well as overall treatment time on local control, was analyzed by Kaplan-Meier calculation of the primary relapse-free survival and Mann-Whitney U testing of the difference in various CIFIs between the tumors that recurred (recurred group) and those that did not (controlled group).

Only CIFI_1–11 influenced local control significantly, with the 5-year primary relapse-free survival rate being 67.9%, 48.4%, and 32.6% in those with CIFI_1–11 of <14, 14, and >14 days (p = 0.0181). The median CIFI_1–11 in the controlled group was significantly lower than that in the recurred group (14 days vs. 15 days; p = 0.0037).

Interruptions during the first 11 fractions, including planned weekend gaps, decrease the effect of radiotherapy, possibly because of successful tumor cell repopulation during the protracted interfraction intervals. The analysis of time in terms of CIFI rather than overall treatment time appears to be a promising area for research.     

High-dose-rate brachytherapy in the treatment of uterine cervix cancer. Analysis of dose effectiveness and late complications

This retrospective analysis aims to report results of patients with cervix cancer treated by external beam radiotherapy (EBR) and high-dose-rate (HDR) brachytherapy.

From September 1992 to December 1996, 138 patients with FIGO Stages II and III and mean age of 56 years were treated. Median EBR to the whole pelvis was 45 Gy in 25 fractions. Parametrial boost was performed in 93% of patients, with a median dose of 14.4 Gy. Brachytherapy with HDR was performed during EBR or following its completion with a dose of 24 Gy in four weekly fractions of 6 Gy to point A. Median overall treatment time was of 60 days. Patient age, tumor stage, and overall treatment time were variables analyzed for survival and local control. Cumulative biologic effective dose (BED) at rectal and bladder reference points were correlated with late complications in these organs and dose of EBR at parametrium was correlated with small bowel complications.

Median follow-up time was 38 months. Overall survival, disease-free survival, and local control at 5 years was 53.7%, 52.7%, and 62%, respectively. By multivariate and univariate analysis, overall treatment time up to 50 days was the only statistically significant adverse variable for overall survival (p = 0.003) and actuarial local control (p = 0.008). The 5-year actuarial incidence of rectal, bladder, and small bowel late complications was 16%, 11%, and 14%, respectively. Patients treated with cumulative BED at rectum points above 110 Gy₃ and at bladder point above 125 Gy₃ had a higher but not statistically significant 5-year actuarial rate of complications at these organs (18% vs. 12%, p = 0.49 and 17% vs. 9%, p = 0.20, respectively). Patients who received parametrial doses larger than 59 Gy had a higher 5-year actuarial rate of complications in the small bowel; however, this was not statistically significant (19% vs. 10%, p = 0.260).

This series suggests that 45 Gy to the whole pelvis combined with four fractions of 6 Gy to point A with HDR brachytherapy is an effective and safe fractionation schedule in the treatment of Stages II and III cervix cancer if realized up to 50 days. To decrease the small bowel complications, we decreased the superior border of the parametrial fields to the S2-S3 level and the total dose to 54 Gy.     

Radiation dose-volume effects on growth hormone secretion

Growth hormone (GH) deficiency is a known consequence of central nervous system irradiation. The relationship between the dose to the hypothalamus and the time to onset of clinically significant GH deficiency is unknown. Conformal radiotherapy (CRT) techniques allow for a more accurate determination of hypothalamic dosimetry. We correlated the dosimetry of the hypothalamus and the peak GH value after CRT in children with localized primary brain tumors.

The arginine tolerance/ -dopa test was performed before (baseline) and repeated 6 and 12 months after CRT in 25 children (median age 4.8 years) with ependymoma (n = 15) or low-grade (n = 8) or high-grade (n = 2) astrocytoma. None had evidence of GH deficiency (arginine tolerance/ -dopa peak GH level >10 ng/mL [10 μg/L]) at baseline. Peak GH levels were modeled as a function of time after CRT and volume of the hypothalamus receiving a dose within the specified intervals of 0–20 Gy, 20–40 Gy, and 40–60 Gy. The model was used to predict the change in the peak GH levels over time (0–12 months) and fit under the assumption that the integral effect of irradiation was a linear sum of the products of the volume receiving a particular dose and the impact of that dose.

The peak GH level declined during the 0–12 months after CRT (p < 0.0001). GH deficiency was observed in 11 children at 6 months and a total of 20 children at 12 months. As expected, the effect of the dose interval 0–20 Gy was smaller than the 20–40-Gy dose interval; the largest effect was noted with the dose interval 40–60 Gy. The peak GH level may be predicted using the following estimating equation within the time limit of 0–12 months: GH(t)=Exp[ln(bGH)−(0.00058V_{0–20 Gy}+0.00106V_{20–40 Gy}+0.00156V_{40–60 Gy})×t], where bGH is the baseline peak GH level, V_{0–20 Gy}, V_{20–40 Gy}, and V_{40–60 Gy} is the percent-volume of the hypothalamus irradiated from 0 to 20 Gy, 20 to 40 Gy, and 40 to 60 Gy, respectively, and t is time after irradiation. When included in the model, the rate of decline in the peak GH response also was influenced by hydrocephalus and tumor location.

The peak GH response within 12 months after CRT depends on hypothalamic dose-volume effects and may be predicted on the basis of a linear model that sums the effects of the entire distribution of dose. The modeled effects may be used to optimize radiotherapy and minimize and treat GH deficiency.