Clinical outcomes of high-dose-rate brachytherapy and external beam radiotherapy in the management of clinically localized prostate cancer

PurposeTo report prostate-specific antigen (PSA) relapse-free survival and treatment-related toxicity outcomes after combining high-dose-rate (HDR) brachytherapy with external beam radiotherapy (EBRT) for patients with clinically localized prostate cancer.Methods and MaterialsBetween 1998 and 2009, 229 patients were treated with HDR brachytherapy followed 3 weeks later by supplemental EBRT. The HDR brachytherapy boost consisted of three fractions of ¹⁹²Ir (5.5–7.5 Gy per fraction), and EBRT consisted of intensity-modulated radiotherapy delivering an additional 45.0–50.4 Gy directed to the prostate gland and seminal vesicles. Median follow-up was 61 months.ResultsSeven-year PSA relapse-free survival for low-, intermediate-, and high-risk patients were 95%, 90%, and 57%, respectively (p < 0.001). Among high-risk patients treated with biological equivalent doses in excess of 190 Gy, 7-year PSA relapse-free survival was 81%. In multivariate analysis, Gleason scores of ≥8 predicted for increased risk of biochemical failure, whereas the use of short-term neoadjuvant androgen deprivation therapy did not influence tumor-control outcomes even among intermediate- or high-risk patients. Seven-year incidence of distant metastases for low-, intermediate-, and high-risk patients were 5%, 3%, and 17%, respectively. Seven-year incidence of late Grade 2 and 3 genitourinary toxicities were 22.1% and 4.9%, respectively and the 7-year incidence of Grade 2 and 3 gastrointestinal toxicities were 1% and 0.4%, respectively.ConclusionHDR prostate brachytherapy in conjunction with supplemental EBRT results in excellent biochemical relapse-free survival rates with a low incidence of severe late genitourinary or gastrointestinal toxicities. The use of short-term neoadjuvant androgen deprivation did not influence long-term biochemical tumor control in this cohort.     

Use of a rectal spacer with low-dose-rate brachytherapy for treatment of prostate cancer in previously irradiated patients: Initial experience and short-term results

BackgroundSalvage brachytherapy in patients with prior pelvic radiation carries a risk of rectal injury. Herein, we report our initial experience using a hydrogel spacer between the prostate and the rectum during salvage brachytherapy.Methods and MaterialsA total of 11 patients with prostate cancer and prior radiotherapy (5 prostate brachytherapy, 2 prostate external beam radiation therapy [EBRT], and 4 rectal cancer EBRT) received ¹²⁵I brachytherapy after attempted placement of 10 cc of a diluted hydrogel spacer between the prostate and rectum.ResultsSpacing was achieved in 8 of the 11 (73%) patients but was not possible in 3 (1 prior brachytherapy and 2 prior EBRT) owing to fibrosis and adhesions. For the 8 patients in whom spacing was accomplished, the median space between the prostate and rectum was 10.9 mm (prior EBRT) vs. 7.7 mm (prior brachytherapy), p = 0.048. Median followup was 15.7 months. One patient developed a prostato-rectal fistula requiring a diverting colostomy. The 16-month estimate of late Grade 3 or 4 gastrointestinal or genitourinary toxicity was 26%. One patient developed lymph node–positive recurrence. The 16-month prostate-specific antigen failure-free survival rate was 89%. Compared with baseline, Expanded Prostate Cancer Index Composite for Clinical Practice urinary quality of life (QoL) was significantly worse at 3 and 6 months but not significantly worse by 1 year. There were no significant changes throughout the study period in bowel or sexual QoL.ConclusionHydrogel spacer placements may be feasible in most patients with prior pelvic radiation. Further followup is needed to determine whether spacer placement will produce long-term improvements in toxicity or QoL.     

Brachytherapy provides comparable outcomes and improved cost-effectiveness in the treatment of low/intermediate prostate cancer

PurposeTo evaluate the cost-effectiveness and outcomes of low-dose-rate (LDR) and high-dose-rate (HDR) brachytherapy compared with intensity-modulated radiation therapy (IMRT) in patients with low/intermediate risk of prostate cancer.Methods and MaterialsOne thousand three hundred twenty-eight patients with low or intermediate risk of prostate cancer were treated with LDR (n = 207), HDR with four fractions (n = 252), or IMRT (n = 869) between January 1992 and December 2008. LDR patients were treated with palladium seeds to a median dose of 120 Gy, whereas HDR patients were treated to a median dose 38.0 Gy (four fractions). IMRT patients received 42–44 fractions with a median dose of 75.6 Gy. Clinical outcomes were compared, including biochemical failure, cause-specific survival, and overall survival.ResultsOverall, no differences in 5-year biochemical control (BC) or cause-specific survival were noted among treatment modalities. The calculated reimbursement for LDR brachytherapy, HDR brachytherapy with four fractions, and IMRT was $9,938; $17,514; and $29,356, respectively. HDR and LDR brachytherapy were statistically less costly to Medicare and the institution than IMRT (p < 0.001), and LDR brachytherapy was less costly than HDR brachytherapy (p = 0.01 and p < 0.001). Incremental cost-effectiveness ratios for cost to Medicare for BC with IMRT were $4045 and $2754 per percent of BC for LDR and HDR brachytherapy, respectively. Incremental cost-effectiveness ratio using institutional cost comparing IMRT with LDR and HDR brachytherapy was $4962 and $4824 per 1% improvement in BC.ConclusionsIn this study of patients with low and intermediate risk of prostate cancer, comparable outcomes at 5 years were noted between modalities with increased costs associated with IMRT.     

Analysis of high–dose rate brachytherapy dose distribution resemblance in CyberKnife hypofractionated treatment plans of localized prostate cancer

The present study is to analyze the CyberKnife hypofractionated dose distribution of localized prostate cancer in terms of high–dose rate (HDR) brachytherapy equivalent doses to assess the degree of HDR brachytherapy resemblance of CyberKnife dose distribution. Thirteen randomly selected localized prostate cancer cases treated using CyberKnife with a dose regimen of 36.25 Gy in 5 fractions were considered. HDR equivalent doses were calculated for 30 Gy in 3 fractions of HDR brachytherapy regimen. The D_5% of the target in the CyberKnife hypofractionation was 41.57 ± 2.41 Gy. The corresponding HDR fractionation (3 fractions) equivalent dose was 32.81 ± 1.86 Gy. The mean HDR fractionation equivalent dose, D_98%, was 27.93 ± 0.84 Gy. The V_100% of the prostate target was 95.57% ± 3.47%. The V_100% of the bladder and the rectum were 717.16 and 79.6 mm³, respectively. Analysis of the HDR equivalent dose of CyberKnife dose distribution indicates a comparable resemblance to HDR dose distribution in the peripheral target doses (D_98% to D_80%) reported in the literature. However, there is a substantial difference observed in the core high-dose regions especially in D_10% and D_5%. The dose fall-off within the OAR is also superior in reported HDR dose distribution than the HDR equivalent doses of CyberKnife.     

Localized prostate cancer with intermediate- or high-risk features treated with combined external beam radiotherapy and iodine-125 seed brachytherapy

ObjectiveThe aim of the study is to compare the results of the combined external beam radiotherapy (EBRT) with iodine-125 seed brachytherapy vs. brachytherapy alone for prostate cancer treatment in patients with intermediate and high risk of disease recurrence.Methods and MaterialsNinety-six patients were treated from January 1998 to December 2006. Twenty-four patients received combined treatment and 72 patients received brachytherapy alone. Patients were classified into intermediate or high risk of recurrence according to the D’Amico’s classification. The prescribed dose for brachytherapy was 145 Gy as monotherapy and 110 Gy for combined treatment. The dose of EBRT was 45 Gy over 5 weeks, with 1.8 Gy daily fractions. Results were analyzed based on Phoenix definition of biochemical recurrence, that is, nadir plus 2 ng/mL.ResultsBiochemical control was achieved by 96% (23 of 24) of patients receiving combined treatment and by 72% (52 of 72) in the group treated by brachytherapy alone (p < 0.015). The addition of EBRT resulted in a 94% biochemical disease-free survival at 5 years; and in brachytherapy alone group, the rate was 54% (p < 0.011). Mean followup was 96 months (24–132 months; confidence interval 95%: 90–102).ConclusionThis study shows that in patients with localized prostate cancer, with intermediate and high risk of biochemical recurrence, the addition of EBRT can confer a significant biochemical control advantage when added to brachytherapy.     

Efficacy of high-dose-rate interstitial brachytherapy in patients with oral tongue carcinoma

PurposeTo evaluate the results of high-dose-rate (HDR)-interstitial brachytherapy (ISBT) in oral tongue carcinomas.Methods and MaterialsBetween September 1999 and August 2007, 50 patients were treated for oral tongue carcinoma with HDR-ISBT. The patient's mean age was 58 years. Forty-two patients were in T1–2 stage and 8 patients were in T3 stage; 16 patients were in N+ stage and 34 patients in N0 stage. Exclusive ISBT was given to 17 patients (34%) in T1–2 N0 stage and complementary to external beam radiotherapy (EBRT) to 33 patients (66%). A perioperative technique was performed on 14 patients. The median total dose was 44 Gy when HDR was used alone (4 Gy per fraction) and 18 Gy when complementary to 50 Gy EBRT (3 Gy per fraction).ResultsThe median followup was 44 months. Actuarial disease-free survival rates at 3 and 5 years were 81% and 74%, respectively. Local failure developed in 7 patients. Actuarial local control (LC) rates were 87% and 79% at 3 and 5 years in T1–2 stage 94.5% and 91% and T3 stage 43% and 43% (with salvage surgery). Exclusive HDR cases showed LC in 100% of the cases, and the combined group (EBRT + HDR) showed LC in 80% and 69% of the cases at 3 and 5 years (p = 0.044). Soft-tissue necrosis developed in 16% and bone necrosis in 4% of the cases.ConclusionsHDR brachytherapy is an effective method for the treatment of oral tongue carcinoma in low-risk cases. Doses per fraction between 3 and 4 Gy yield LC and complication rates similar to low-dose rate. The perioperative technique promises encouraging results.     

The use of supplemental external beam radiotherapy in men with low-risk prostate cancer undergoing brachytherapy before and after the 1999 American Brachytherapy Society Guideline statement

PurposeIn 1999, the American Brachytherapy Society (ABS) recommended brachy-monotherapy for men with low-risk prostate cancer because of the potential for increased toxicity with combined external beam radiotherapy (EBRT) and brachytherapy without the proof of increased efficacy. We investigated the patterns of care in the community in this patient population before and after the reporting of the ABS guideline.Methods and MaterialsThe study cohort consisted of 4943 men (median age, 69.0 years) with low-risk prostate cancer treated with brachytherapy with or without supplemental EBRT from 1991 to 2007 across 21 community radiation oncology centers. Multivariable logistic regression analysis was performed to determine if there was a significant association between the year of brachytherapy, prostate-specific antigen level, clinical tumor (T) category, patient's age, and the use of supplemental EBRT.ResultsSupplemental EBRT was used in 647 men (13%). The EBRT use initially increased until 2001 and then decreased yielding a significant association (adjusted odds ratio [AOR], 0.92; p < 0.001) between the EBRT use and the year of brachytherapy using a quadratic formulation. Specifically, EBRT use peaked at 24.6% in 2001 and subsequently declined to 3.3% by 2007. Men with clinical category T2a as compared with T1c disease (AOR, 1.43; p < 0.001) were more likely to receive combined modality therapy.ConclusionsThe use of supplemental EBRT in men with low-risk prostate cancer treated with brachytherapy has decreased since 2001. This change in practice patterns suggests gradual adoption of the 1999 ABS practice guidelines.     

High-dose-rate brachytherapy in combination with conformal external beam radiotherapy in the treatment of prostate cancer

PurposeTo report long-term outcomes for treatment of prostate cancer using dose escalation with high-dose-rate (HDR) brachytherapy and 3-dimensional conformal external beam radiotherapy (3DCRT), and compare them with outcomes for treatment of prostate cancer with 3DCRT alone at the same institution.Methods and MaterialsFrom 1998 to 2003, 587 patients were treated for clinically localized prostate cancer. Patients received either 3DCRT (median, 46 Gy) with a single HDR brachytherapy implant (196 patients) delivering a fractionated dose of 18 Gy (combined group) or 3DCRT (median, 70 Gy; 387 patients; “3DCRT alone”). There were 41.9% patients with intermediate-risk and 42.6% with high-risk disease. In all, 441 patients (75.1%) received neoadjuvant and 116 patients (19.8%) received adjuvant androgen deprivation therapy. The American Society of Therapeutic Radiology and Oncology Phoenix definition for biochemical failure was used.ResultsThe median followup was 5.5 years. The 5- and 7-year biochemical control (BC) rates were 82.5% and 80.3%, respectively, for the combined group and 81.3% and 71%, respectively, for 3DCRT alone; for overall survival, they were 91.9% and 89.5% vs. 88.7% and 86.2%, respectively, whereas for cause-specific survival, they were 96.9% and 96.1% vs. 97.6% and 96.2%, respectively. Cox proportional hazard regression analysis for BC revealed that low Gleason grade, HDR brachytherapy combined with 3DCRT, and adjuvant androgen deprivation therapy were significant in predicting BC. Radiation Therapy Oncology Group Grade 3 late urinary and rectal morbidity rates were 7.1% and 0%, respectively. No Grade ≥4 reactions were detected.ConclusionsHDR brachytherapy combined with 3DCRT was associated with improved BC and minimal toxicity in patients with unfavorable prostate cancer compared with conventional 3DCRT.     

Prostate gland edema after single-fraction high-dose rate brachytherapy before external beam radiation therapy

PurposeHigh–dose rate brachytherapy (HDRB) is frequently used as a boost to external beam radiation therapy (EBRT) in prostate cancer patients. With the increasing use of small planning target volume margins in EBRT, prostatic edema induced by HDRB can be a contributing factor to geometric miss when HDRB is performed before or during EBRT. We assessed prostate gland volumetric change after single-fraction HDRB and its impact on definition of treatment volume for EBRT.Methods and MaterialsThirty-one consecutive patients with intermediate-risk prostate cancer treated with single-fraction HDRB (10 Gy) combined with hypofractionated EBRT were analyzed. A second CT scan was performed 7 days after HDRB, and images were coregistered with the planning CT scan that contained the original clinical target volume (CTV). The post-HDRB prostate CTV volume was compared with the original CTV by a single observer.ResultsAll patients presented volumetric variation. In most cases (68%), the prostate increased in volume, whereas it decreased in 32%. The mean prostatic volume was 42.2 cc before HDRB and 43.6 cc after HDRB, representing a mean volume difference of 3.4%, ranging from ?14.2% to 23.8% (p = 0.756). This difference is the result of mean changes of 0.6 mm (?6.1 to 6.6) in the anterior–posterior, 0.5 mm (?5.5 to 3.0) in the lateral, and 0.2 mm (?5.0 to 5.0) in the superior–inferior axes.ConclusionsAlthough a nonsignificant volumetric change occurs after single-fraction HDRB, individual variations on specific axis could lead to important uncertainties during EBRT.     

High-dose-rate afterloading intraluminal brachytherapy for advanced inoperable rectal carcinoma

PurposeHigh-dose-rate (HDR) intraluminal brachytherapy for advanced or inoperable tumors of the rectum has been used both palliatively and to dose escalate after chemoradiation for curative treatment.MethodsBetween 1993 and 2007, 79 patients were treated with HDR afterloading brachytherapy for rectal cancer; 70 patients had adenocarcinoma of the rectum; and 9 patients had squamous cell carcinoma of the anal canal. Fifty-two patients had localized disease but were unfit for major surgery and received radiotherapy with radical intent. Twenty-seven patients with advanced or metastatic disease received palliative treatment. The median age was 82 years (range, 33–97). Radical treatment comprised either chemoradiation followed by intraluminal brachytherapy delivering 12 Gy at 1 cm in two fractions or radical monotherapy delivering up to 36 Gy at 1 cm in six fractions two to three times weekly. Palliative HDR brachytherapy schedules were predominantly 10 Gy at 1 cm single dose.ResultsObjective local tumor response was seen in 41 of 48 assessable patients (85%); of whom, 28 patients (58%) had a complete response and 13 (27%) had a partial response. The most common symptom was rectal bleeding, which was controlled with a complete response rate of 63%. The median duration of the symptom response was 3 months (range, 1–73), and the median survival of the palliative patients was 6 months (range, 1 week–37 months). The median survival for patients treated with radical intent was 18.5 months (range, 2–119). Six patients reported late toxicity with three cases of rectal ulcer, two strictures, and one fistula.ConclusionsIntraluminal HDR brachytherapy is effective as local treatment in both the radical and palliative setting, with high tumor and symptom response rates, and acceptable late toxicity.     

Electronic brachytherapy for postsurgical adjuvant vaginal cuff irradiation therapy in endometrial and cervical cancer: A retrospective study

PurposeA new platform for brachytherapy called electronic brachytherapy (EBT) has been developed, which uses a miniature X-ray source to generate low-energy radiation. A retrospective study of adverse events and clinical outcomes in patients treated with EBT to the vaginal cuff, either as monotherapy or in combination with external beam radiation therapy (EBRT), was conducted.Methods and MaterialsMedical records were reviewed from 16 patients treated with postoperative EBT for endometrial (n = 13) or cervical cancer (n = 3) between February 2009 and November 2010. Patients received either intracavitary vaginal EBT alone or EBT in combination with EBRT. The radiobiologic effectiveness of EBT was assumed to be one.ResultsMedian follow-up was 20.5 months (range, 7–36 months). When EBT was used alone (n = 5), the median dose per fraction, number of fractions, and total dose delivered were: 6 Gy (range, 5.5–6.2 Gy), 5 fractions (range, 5–6), and 30 Gy (range, 30–34 Gy), respectively. When EBT was combined with EBRT, the EBT component median dose per fraction, number of fractions, and total dose delivered were: 5 Gy (range, 4.5–7 Gy), 2 fractions (range, 2–4), and 14 Gy (range, 9–20 Gy), respectively. The median EBRT dose was 45 Gy (range, 45–49.2 Gy). Our local control rate, locoregional (pelvic) control rate, and overall survival rate were 94%, 94%, and 88%, respectively. Of the 16 patients, 4 patients reported Grade 2 or greater toxicity (25%); however, there were no Grade 4–5 adverse events. Gynecologic, genitourinary, and gastrointestinal adverse events accounted for 57% (n = 4), 43% (n = 3), and 0% (n = 0) of all Grade 2 or greater side effects. No Grade 2 or higher toxicities were noted in patients treated with EBT alone.ConclusionEBT is an acceptable means of delivering postoperative vaginal brachytherapy and appears comparable with other methods; as the sole method of treatment, the toxicity rates of EBT are low.     

Long-term outcome for prostate cancer using pseudo pulse–dosed rate brachytherapy,external beam radiotherapy,and hormones

PurposeWe report the long-term outcomes of pulse-dose rate (PDR) brachytherapy used in a nonstandard style (pseudo-PDR) with an high-dose rate brachytherapy technique in conjunction with external beam radiotherapy (EBRT) and hormonal manipulation on prostate cancer (PC).Methods and MaterialsWe treated 253 patients with Stage T1–T3 N0M0 PC, between December 1999 and March 2006. All patients received neoadjuvant androgen deprivation for a median 6 months. Treatment consisted of three pulses of pseudo-PDR brachytherapy to a median dose of 18 Gy with 50.4 Gy in 28 fractions of EBRT.ResultsAt a median 6 years followup, (range, 1–11 years), 5-year overall survival was 92%, and PC-specific survival was 96%. The 5-year biochemical control (biochemical no evidence of disease) by the Phoenix definition for low-, intermediate-, and high-risk groups was 95%, 90%, and 71%, respectively (p < 0.00001). At 6 years, the incidence of Radiotherapy Oncology Group Grade 2 and 3 genitourinary toxicity was 1% and 6%; Radiotherapy Oncology Group Grade 2 and 3 gastrointestinal toxicity was 4% and 0%. Erectile preservation at 3 years was 58%. The Phoenix definition best predicted clinical failure with a high specificity (94%).ConclusionsPseudo-PDR brachytherapy plus EBRT with limited neoadjuvant hormonal manipulation is an effective treatment option in localized PC, with minimal and tolerable morbidity and provides excellent control. This technique of a modified PDR-delivery technique appears as effective as high-dose rate therapy.     

Phase I/II trial of single-fraction high-dose-rate brachytherapy-boosted hypofractionated intensity-modulated radiation therapy for localized adenocarcinoma of the prostate

PurposeA Phase I/II protocol was conducted to examine the toxicity and efficacy of the combination of intensity-modulated radiation therapy (IMRT) with a single-fraction high-dose-rate (HDR) brachytherapy implant.Methods and MaterialsFrom 2001 through 2006, 26 consecutive patients were treated on the trial. The primary objective was to demonstrate a high rate of completion without experiencing a treatment-limiting toxicity. Eligibility was limited to patients with T stage ≤2b, prostate-specific antigen (PSA) ≤20, and Gleason score ≤7. Treatment began with a single HDR fraction of 6 Gy to the entire prostate and 9 Gy to the peripheral zone, followed by IMRT optimized to deliver in 28 fractions with a normalized total dose of 70 Gy. Patients received 50.4 Gy to the pelvic lymph node. The prostate dose (IMRT and HDR) resulted in an average biologic equivalent dose >128 Gy (α/β = 3). Patients whose pretreatment PSA was ≥10 ng/mL, Gleason score 7, or stage ≥T2b received short-term androgen ablation.ResultsMedian followup was 53 months (9–68 months). There were no biochemical failures by either the American Society of Therapeutic Radiology and Oncology or the Phoenix definitions. The median nadir PSA was 0.32 ng/mL. All the 26 patients completed the treatment as prescribed. The rate of Grade 3 late genitourinary toxicity was 3.8% consisting of a urethral stricture. There was no other Grade 3 or 4 genitourinary or gastrointestinal toxicities.ConclusionsSingle-fraction HDR-boosted IMRT is a safe effective method of dose escalation for localized prostate cancer.     

Clinical outcomes of high-dose-rate interstitial gynecologic brachytherapy using real-time CT guidance

PurposeTo evaluate clinical outcomes of CT-guided high-dose-rate (HDR) interstitial brachytherapy for primary and recurrent gynecologic cancer.Methods and MaterialsRecords were reviewed for 68 women (34 with primary disease and 34 with recurrence) treated with CT-guided HDR interstitial brachytherapy between May 2005 and September 2011. Interstitial application was performed under general anesthesia using an iterative approach of catheter insertion and adjustment with serial image acquisition by CT in a dedicated brachytherapy suite. The median fractional brachytherapy dose was 3.9 Gy delivered twice daily in seven fractions. The median cumulative dose in equivalent 2-Gy fractions was 74.8 Gy. Actuarial survival estimates were calculated using the Kaplan–Meier method, and toxicity was reported by Common Toxicity Criteria.ResultsPrimary disease sites were endometrial (34), cervical (17), vaginal (11), ovarian (3), and vulvar (3). Median age was 61.5 years, and tumor size at diagnosis was 3.4 cm. Median D₉₀ and V₁₀₀ were 73.6 Gy and 87.5%, respectively; median D_2cc for bladder, rectum, and sigmoid were 67.1, 64.6, and 53.7 Gy, respectively. With a median followup of 17 months, actuarial rates of local control, progression-free survival, and overall survival at 2 years for all patients were 86%, 60%, and 64%, respectively. There were 9 grade 3 late toxicities (six gastrointestinal and three vulvovaginal).ConclusionsHDR interstitial brachytherapy with CT-guided catheter placement results in acceptable local control, toxicity, and survival rates for women with primary or recurrent gynecologic cancer. Durable pelvic control may be achieved in most patients with this specialized brachytherapy technique.     

An age-corrected matched-pair study of erectile function in patients treated with dose-escalated adaptive image-guided intensity-modulated radiation therapy vs. high-dose-rate brachytherapy for prostate cancer

PurposeTo compare erectile dysfunction (ED) after adaptive dose-escalated image-guided intensity-modulated radiotherapy (IG-IMRT) and high-dose-rate interstitial brachytherapy (HDR) monotherapy.Methods and MaterialsLow- and intermediate-risk prostate cancer patients treated with IG-IMRT or HDR were matched on pretreatment ED, age, Gleason score, T-stage, and prostate specific antigen. Patients who received androgen deprivation therapy were excluded. ED was graded by Common Terminology Criteria for Adverse Events v4. Actuarial rates of ED were computed by the Kaplan–Meier method.ResultsThere were 384 patients with median followup of 2.0 years (0.5–6.1) for IG-IMRT and 2.0 years (0.5–8.7) for HDR. The median IG-IMRT dose was 75.6 Gy and HDR dose 38 Gy in four fractions. For patients with no pretreatment ED, actuarial rates of requiring intervention (Grade ≥2 ED) at 3 years were 31% for IG-IMRT and 19% for HDR (p = 0.23), and impotence despite medical intervention (Grade 3) were 0% for IG-IMRT and 6% for HDR (p = 0.06). For patients with Grade 1 pretreatment ED, Grade ≥2 ED at 3 years were 47% for IG-IMRT and 34% for HDR (p = 0.79), and Grade 3 ED were 15% in both groups (p = 0.59). For patients with Grade 2 pretreatment ED, Grade 3 ED at 3 years were 22% for IG-IMRT and 37% for HDR (p = 0.70). No variables were predictive of Grade ≥2 ED following treatment.ConclusionsRates of ED requiring medical intervention for both IG-IMRT and HDR are low and equivalent. Even patients with ED before treatment are likely to maintain potency with medication use at 3 years following treatment.     

The equivalent dose contribution from high-dose-rate brachytherapy to positive pelvic lymph nodes in locally advanced cervical cancer

PurposeDefinitive radiation therapy for locally advanced cervical cancer involves external beam radiation therapy (EBRT) and high-dose-rate (HDR) brachytherapy. There remains controversy and practice pattern variation regarding the optimal radiation dose to metastatic pelvic lymph nodes (LNs). This study investigates the contribution of the pelvic LN dose from HDR brachytherapy.Methods and MaterialsFor 17 patients with 36 positive pelvic LNs, each LN was contoured on a computed tomography (CT) plan for EBRT and on brachytherapy planning CTs using positron emission tomographic images obtained before chemoradiation. The mean delivered dose from each plan was recorded, and an equivalent dose in 2-Gy fractions (EQD2) was calculated. A Student's t test was performed to determine if the mean delivered dose is significantly different from the mean prescribed dose and EQD2.ResultsThe average prescribed dose from the total EBRT was 54.09 Gy. The average prescribed HDR dose to International Commission on Radiation Units point A was 26.81 Gy. The average doses delivered to the involved LNs from EBRT and brachytherapy were 54.25 and 4.31 Gy, respectively, with the corresponding EQD2 of 53.45 and 4.00 Gy. There was no statistically significant difference (p < 0.05) between the mean delivered and the prescribed doses for EBRT and between the delivered dose and the EQD2 for EBRT and brachytherapy.ConclusionsOur study shows that the HDR contribution is 7% (4.00 Gy) of the total EQD2 (57.45 Gy). The HDR contribution should be accounted for when prescribing the EBRT boost dose to pelvic LNs for the optimal therapeutic dose.     

High-dose-rate interstitial brachytherapy as monotherapy in one fraction and transperineal hyaluronic acid injection into the perirectal fat for the treatment of favorable stage prostate cancer: treatment description and preliminary results

PurposeTo evaluate the technical feasibility, acute and late genitourinary (GU) toxicity, and gastrointestinal toxicity after high-dose-rate (HDR) brachytherapy as monotherapy in one fraction with transperineal hyaluronic acid injection into the perirectal fat to displace the rectal wall away from the radiation sources to decrease rectal toxicity.Methods and MaterialsBetween April 2008 and January 2010, 40 consecutive patients were treated with favorable clinically localized prostate cancer; the median followup was 19 months (range, 8–32). No patients received external beam radiation, and 35% received hormone therapy before brachytherapy. All patients received one implant and one fraction of HDR. Fraction dose was 19 Gy. Toxicity was reported according to the Common Toxicity Criteria for Adverse Event, Version 4.0.ResultsAll patients tolerated the implantation procedure very well with minimal discomfort. No intraoperative or perioperative complications occurred. Acute toxicity Grade 2 or more was not observed in any patients. No chronic toxicity has been observed after treatment. Logistic regression showed that the late Grade 1 GU toxicity was associated with D₉₀ (p = 0.050). The 32-month actuarial biochemical control was 100% and 88%, respectively (p = 0.06) for low- and intermediate-risk groups.ConclusionsThis is the first published report of the use of HDR brachytherapy as monotherapy in one fraction for patients with favorable-risk prostate cancer. This protocol is feasible and very well tolerated with low GU morbidity, no gastrointestinal toxicity, and the same level of low-dose-rate biochemical control at 32 months.     

High-dose-rate brachytherapy boost for carcinoma of external auditory canal

PurposeTo report dosimetry and outcome in a case of early stage carcinoma of external ear (T1N0M0) treated with radical radiotherapy alone using a combination of external beam radiotherapy (EBRT) and intracavitary irradiation with a high-dose-rate (HDR) ¹⁹²Ir remote afterloading system.Methods and MethodsA 64-year-old gentleman who was diagnosed as T1N0M0 carcinoma of external ear was treated with combination of external beam radiation therapy followed by brachytherapy (BRT). A total dose of 40 Gy was delivered by EBRT, following which a 6-Fr catheter for the HDR ¹⁹²Ir remote afterloader, fixed by a customized acrylic mold, was inserted into the external auditory canal (EAC) and a total intracavitary radiation dose of 22.5 Gy (4.5 Gy/F) was given.ResultsEvaluation at the completion of treatment and at the end of 4-year followup revealed no evidence of the disease.ConclusionsIn the radical treatment of early stage EAC carcinoma, combination of external beam radiation therapy and BRT may be a modality of choice for its efficacy, less severe side effects, and better cosmetic results.     

External beam radiotherapy plus high-dose-rate brachytherapy for treatment of locally advanced prostate cancer: The initial experience of the Catalan Institute of Oncology

PurposeThe objective of this study was to report initial outcomes in patients with locally advanced prostate cancer (CaP) who underwent external beam radiation therapy (EBRT) treatment combined with high-dose-rate brachytherapy (HDR-BT) as a boost.Methods and MaterialsFrom 2002 to 2007, 114 CaP patients underwent EBRT followed by ¹⁹²I HDR-BT. The patients were classified into intermediate- (Group 1) or high- (Group 2) risk groups. The mean total EBRT dose was 60.0 Gy (95% confidence interval [CI]: 59.9–60.1) at 2 Gy per fraction. After a mean of 20.6 days (95% CI: 18.4–22.8), all the patients received a single-fraction 9-Gy dose of HDR-BT boost. Of the 114 patients in the study, 103 (90.4%) underwent up to 3 years of complete androgen deprivation therapy after diagnosis.ResultsThe mean followup for the entire group was 32.1 months (95% CI: 29.9–34.4). The 4-year biochemical failure-free survival rate was 97.4% and treatment was well-tolerated.ConclusionsPreliminary biochemical control rates after EBRT plus one fraction of 9-Gy HDR-BT are encouraging. This atypical fractionation schedule is cost-effective and reduces patient discomfort and treatment-related risks. More followup is required to confirm these findings.