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1.
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.  相似文献   


2.
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 (CIFI1–6, CIFI1–11, CIFI1–16, and CIFI1–21, 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 CIFI1–11 influenced local control significantly, with the 5-year primary relapse-free survival rate being 67.9%, 48.4%, and 32.6% in those with CIFI1–11 of <14, 14, and >14 days (p = 0.0181). The median CIFI1–11 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.  相似文献   


3.
The purpose of this study was to measure the effect of megestrol acetate (MA) on weight loss and quality of life (QOL) in patients with cancer of the lung or head and neck undergoing curative radiation therapy.

This was a Phase III, placebo-controlled, double-blind randomized study. Patients received either 800 mg/day of MA (20 milliliters po qAM) or placebo over a 12-week period. Patients received radiation of the head and neck or thorax using a dose of at least 50 Gy, either alone or with chemotherapy. Weight was assessed weekly, whereas QOL was assessed at baseline and at 4, 8, and 12 weeks.

Patient characteristics on the MA arm (16 lung, 12 head/neck; mean age: 60 years) were similar to those on the placebo arm (17 lung, 11 head/neck; mean age: 65.8 years). Patients in the MA group had a mean weight loss over 12 weeks of 2.7 pounds, whereas the placebo group had a mean weight loss of 10.6 pounds. There was a significant time by treatment interaction (p = 0.001), with the difference in weight between treatment groups being most pronounced after 6 weeks. Although overall QOL was similar in both arms of the study, several QOL subscale items did differ significantly. Compared to the placebo-treated patients, head-and-neck cancer patients in the MA arm reported the ability to eat as much as they liked (p = 0.02 at 12 weeks), and lung cancer patients in the MA arm reported significantly better appetite at 4 weeks (p = 0.03) and 8 weeks (p = 0.001).

MA used prophylactically is useful as an appetite stimulant; it can help patients maintain weight over the course of curative radiotherapy of the head and neck or lung and can improve specific aspects of QOL.  相似文献   


4.
: It has been suggested that postoperative tumor cell proliferation may influence the outcome of advanced head and neck squamous cell carcinomas treated by surgery and postoperative radiotherapy. This Phase I pilot study was undertaken to determine the feasibility of a biphasic accelerated radiotherapy regimen with early and late concomitant boost delivery for postoperative treatment of patients with advanced head and neck cancers.

: From April 1993 to April 1994, 29 patients with advanced head and neck cancers were enrolled in this study after they underwent complete surgical resection. The basic radiation course delivered a median dose of 49 Gy in 25 fractions over 5 weeks at 1.8–2 Gy/fraction. The concomitant boost was delivered to the high-risk areas as a second daily fraction during the first (1.4 Gy/fraction) and fifth weeks (1.6 Gy/fraction). The total dose to the high-risk areas was 64 Gy in 35 fractions over 5 weeks.

: Twenty-seven patients (93%) completed the treatment without interruptions. Only two patients experienced severe acute toxicity requiring treatment breaks of 6 and 8 days, respectively. All patients developed confluent mucositis; in 69% of the cases it covered >50% of the treated surface. No patient developed Grade 5 (ulceration/bleeding) mucosal reaction. Mucositis required a median time of 7 weeks for complete healing (range 3–43. Two patients developed transient bone exposure. The median weight loss was 5.5% of pretreatment body weight (range 1.2–17.1%), and four patients required nutritional with nasogastric feeding tube.

: The results of this study show that this biphasic acceleration regimen is feasible with acceptable acute toxicity.  相似文献   


5.
To prospectively evaluate the quality of life (QOL) before, at completion, and after therapy for patients receiving an accelerated fractionation schedule of radiotherapy for advanced, unresectable non-small-cell lung cancer in a Phase II multi-institutional trial.

The Functional Assessment of Cancer Therapy-Lung (FACT-L) patient questionnaire was used to score the QOL in patients enrolled in the Eastern Cooperative Oncology Group Phase II trial (ECOG 4593) of hyperfractionated accelerated radiotherapy in non-small-cell lung cancer. Radiotherapy (total dose 57.6 Gy in 36 fractions) was delivered during 15 days, with three radiation fractions given each treatment day. The protocol was activated in 1993, and 30 patients had accrued by November 1995. The FACT-L questionnaire was administered at study entry (baseline), on the last day of radiotherapy (assessment 2), and 4 weeks after therapy (assessment 3). The FACT-L includes scores for physical, functional, emotional, and social well-being (33 items), and a subscale of lung cancer symptoms (10 additional items). The summation of the physical, functional, and lung cancer symptom subscales (21 items) constitutes the Trial Outcome Index (TOI), considered the most clinically relevant outcome measure in lung cancer treatment trials.

The FACT-L completion rates at the designated study time points were as follows: baseline, 30 of 30 (100%); assessment 2, 29 (97%) of 30; and assessment 3, 24 (80%) of 30. At treatment completion, statistically significant declines in QOL scores were noted, compared with baseline for physical and functional well-being. Emotional well-being scores improved at both assessment 2 and assessment 3. The physical and functional scores returned approximately to baseline values at assessment 3. The change in TOI score was evaluated as a function of the clinical response to treatment, toxicity grade, and survival; no clear association was noted. A trend for the largest decrease in QOL was noted for patient groups with shorter survival times. The mean change in the TOI score from baseline to assessment 3 was −8.96 for patients surviving < 52 weeks vs. −0.95 for those surviving > 52 weeks.

The FACT-L questionnaire can be successfully administered to non-small-cell lung cancer patients enrolled in a prospective Phase II trial of accelerated radiation fractionation. The decrement in physical and functional QOL during treatment returned to baseline level at 4 weeks after treatment. Emotional well-being improved at all time points. A trend was noted for shorter survival times in patients with the largest negative change in TOI score. These data suggest that the clinical use of hyperfractionated accelerated radiotherapy did not cause a significant, long-term decrease in the QOL of the treated patients, and that it is feasible to perform a QOL study of patients enrolled in such a trial.  相似文献   


6.
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.  相似文献   


7.
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.  相似文献   


8.
To test the hypothesis that androgen ablation before and during radiotherapy for locally advanced carcinoma of the prostate may, by reducing tumor bulk and enhancing tumor cell kill, improve locoregional control and ultimately survival.

The study was conducted from 1987 to 1991. Eligible patients were those with bulky tumors (T2–T4) with or without pelvic lymph node involvement and without evidence of distant metastases. They were randomized to receive goserelin, 3.6 mg every 4 weeks; and flutamide, 250 mg t.i.d. for 2 months before radiation therapy and during radiation therapy (Arm I), or radiation therapy alone (Arm II). Of 471 randomized patients, 456 were evaluable: 226 on Arm I and 230 on Arm II.

As of November 1999, the median follow-up has reached 6.7 years for all patients and 8.6 years for alive patients. At 8 years, androgen ablation has been associated with an improvement in local control (42% vs. 30%, p = 0.016), reduction in the incidence of distant metastases (34% vs. 45%, p = 0.04), disease-free survival (33% vs. 21%, p = 0.004), biochemical disease-free SURVIVAL = PSA <1.5 (24% vs. 10%, p < 0.0001), and cause-specific mortality (23% vs. 31%, p = 0.05). However, subset analysis indicates that the beneficial effect of short-term androgen ablation appears preferentially in patients with Gleason score 2–6. In that population, there is a highly significant improvement in all endpoints, including survival (70% vs. 52%, p = 0.015). In patients with Gleason 7–10 tumors, the regimen has not resulted in a significant enhancement in either locoregional control or survival.

In patients with Gleason score 2–6 carcinoma of the prostate, a short course of androgen ablation administered before and during radiotherapy has been associated with a highly significant improvement in local control, reduction in disease progression, and overall survival.  相似文献   


9.
The role of brachytherapy in early-stage nasopharyngeal carcinoma   总被引:7,自引:0,他引:7  
To present the treatment results and assess the optimal radiation dose and the role of brachytherapy in early stage nasopharyngeal cancer (NPC).

One hundred eighty-three patients with Stage I and II (American Joint Committee on Cancer Staging System, 1987) NPC completed the planned radiotherapy in our institution from 1979 to 1991. In 133 patients, radiotherapy was given to the nasopharynx by external beam to 64.8–68.4 Gy. Further boost was done by high dose rate (HDR) brachytherapy for 5–16.5 Gy in one to three fractions. For the remaining 50 patients, a course of external radiotherapy to the nasopharynx for 68.4–72 Gy was given to nasopharynx. Age (>40 or not) sex, neck boost or not, brachytherapy, and irradiation dose were analyzed to determine significant factors that influence the probabilities of local control and actuarial survival.

The 5-year disease-specific survival was 85.8% and local control was 83%. Only the brachytherapy and irradiation dose significantly affected the results. The use of the brachytherapy had significant impact on overall survival and local control. Furthermore, we compared the prognostic effect of various radiation dosage among Group I of 50 patients (<72.5 Gy, no brachytherapy, excluding four patients who received brachytherapy), Group II of 71 patients (72.5–75 Gy; one to two fractions of brachytherapy), and Group III of 58 patients (>75 Gy; three fractions of brachytherapy). Five-year disease-specific survival rates of Group I, Group II, and Group III were 77, 95.5, and 82.4%, respectively. Five-year local control rates were: 73.7, 93.9, and 79.5%. We found that the Group II had the best actuarial survival and local control rate (log-rank test, p < 0.05). Most patients receiving brachytherapy encountered foul odor because of nasopharynx crust; 12 of them had palate or sphenoid sinus floor perforation or nasopharynx necrosis. None of the patients without brachytherapy experienced the same complications.

The optimal radiotherapy dose to the nasopharnyx area in early stage NPC may be within 72.5 to 75 Gy by our treatment protocol. A dose of more than 75 Gy did not have significant local control or survival advantage. The use of brachytherapy to elevate radiation dose had significant local control and survival benefit for early stage NPC patients, but the fractionation size should be decreased to reduce the complications.  相似文献   


10.
Acute radiation thyroiditis   总被引:1,自引:0,他引:1  
: Radiation-induced thyroid dysfunction is considered a late effect. We prospectively assessed acute reactions of thyroid to external neck irradiation.

This study included 22 patients in whom the thyroid was incidentally exposed to therapeutic does of radiation. Thyroid function tests included measurements of serum thyroid stimulating hormone (TSH), free and total triiodothyronine (T3) and thyroxine (T4), thyroglobulin, and antithyroid antibodies. These tests were performed before radiotherapy, and 3 and 6 months after the beginning of radiotherapy.

: Mean serum levels of TSH were 1.53, 0.55, 0.78, 2.14, and 7.57 μU/ml before radiotherapy, after 40 Gy irradiation, 2 weeks after the end of radiotherapy, and 3 and 6 months after radiotherapy, respectively. Thus, levels of TSH exhibited two phases: a significant decrease during radiotherapy (thyroxic phase) and an increase after radiotherapy (hypothyroid phase) (baseline vs. 40 Gy: p < 0.0001, baseline vs. 6 months: p = 0.003). Increases of thyroid hormones were subtle during radiotherapy.

: We believe that radiation promotes release of excessive amounts of thyroid hormones during radiotherapy owing to suppression of TSH secretion. In addition to the late damage (hypothyroidism), thyrotoxicosis occurs when the thyroid gland receives a therapeutic doses of external radiation.  相似文献   


11.
A Phase II multicenter trial testing an accelerated regimen of radiotherapy in locally advanced and inoperable cancers of the head and neck, in patients selected on the basis of 5-bromo-2-deoxyuridine/DNA flow cytometry-derived tumor potential doubling time (Tpot).

From September 1992 to September 1993, 23 patients consecutively diagnosed to have locally advanced, inoperable carcinomas of the oral cavity and the oropharynx, with Tpot of ≤ 5 days, received an accelerated radiotherapy regimen (AF) based on a modification of the concomitant boost technique: 2 Gy/fraction once a day, delivered 5 days a week up to 26 Gy, followed by 2 Gy/fraction twice a day, with a 6-h interval, one of the two fractions being delivered as a concomitant boost to reduced fields, up to 66 Gy total dose (off-cord reduction at 46 Gy), shortening the overall treatment time to 4.5 weeks. A contemporary control group of 46 patients with Tpot of >5 days or unknown was treated with conventional fractionation (CF):2 Gy/fraction once a fay, 5 days a week, up to 66 Gy in 6.5 weeks, with fields skrinkage after 46 Gy.

All patients completed the accelerated regimen according to protocol and in the prescribed overall treatment time. Immediate tolerance was fairly good: 65% of the patients inthe AF group experienced Grade 3 mucositis vs. 45% in thee CF group (p = n.s.). Symptoms related to mucosal reactions seemed to persist longer in AF than in CF patients. The crude proportion of mild (Grades 1 and 2) late effects on skin (p < 0.01) and salivary glands (p < 0.05) was higher in AF than in CF patients, although these reactions dis not exceed the limits of tolerance. Three patients in the AF and 1 in the CF arm experienced a late Grade 4 bone complication. Actuarial estimates of severe (Grade 3 and 4) late complications showed a 2-year hazard of 33.3% in the AF arm and 49.7% in CF (p = NS). The actuarial 2-year local control rate of the AF patients was 49.4%, while actuarial 2-year overall survival for the same patients was 43.5%.

The results suggested that this accelerated regimen is worth testing in a controlled randomized trial to compare different accelerated schedules. Our findings also confirmed the 5-bromo-2-deoxyuridine/DNA flow cytometry technique as a suitable method of evaluating tumor cell kinetics in multicenter clinical studies, on conditions thal all measurements are carried out by one most experienced laboratory.  相似文献   


12.
To test the correlation of LENT/SOMA and RTOG/EORTC late-effect scales for rectum and bladder, 116 cases with gynecologic malignancies that were treated with radiotherapy were assessed with both scales.

All cases had been treated at least 6 months before the date of assessment with external beam radiotherapy (50–54 Gy to midline) and 1–2 fractions of HDR brachytherapy (2 × 8.5 Gy to point-A for 32 inoperable cases; 1 × 9.25 Gy to 5–9 mm from the ovoid surface for 84 postoperative cases). The patients were questioned with both scales, and the correlation between the two scales was analyzed by Spearman’s rho (rank correlation) test.

There were 64 cases with uterine cervix carcinoma and 52 cases with endometrium carcinoma, The overall (external + brachy) doses to ICRU points were 57.8 ± 3.8 Gy for rectum and 59.3 ± 4.9 Gy for bladder. The statistical analysis of LENT/SOMA and RTOG/EORTC scales revealed a very good correlation for rectum (r = 0.81; p < 0.01) and a good correlation for bladder (r = 0.72; p < 0.01).

The LENT/SOMA system is a further step on the reporting of late radiation effects. Some modifications will improve its precision, and multicentric randomized studies are needed to test its validity.  相似文献   


13.
Purpose: The standard treatment for patients with unresectable or medically inoperable non-small cell lung cancer (NSCLC) and good prognostic factors (e.g., weight loss [WL] ≤5% and Karnofsky performance status [KPS] ≥70) is induction chemotherapy followed by definitive radiotherapy to the primary site at 1.8–2.0 Gy per fraction with a total dose of 60–63 Gy to the target volume. Patients with poor prognostic factors usually receive radiotherapy alone, but the fractionation schedule and total dose have not been standardized. To attempt to optimize irradiation doses and schedule, we compared the effectiveness of accelerated radiotherapy (ACRT) alone to 45 Gy at 3 Gy per fraction with standard radiation therapy (STRT) of 60–66 Gy at 2 Gy per fraction in regard to tumor response, local control, distant metastasis, toxicity, and survival.

Methods and Materials: Fifty-five patients treated with radiation for NSCLC at The University of Texas M. D. Anderson Cancer Center between 1990 and 1994 were identified. All 55 patients had node-positive, and no distant metastasis (N+, M0) of NSCLC. Two cohorts were identified. One cohort (26 patients) had borderline poor prognostic factors (KPS less than 70 but higher than 50, and/or WL of more than 5%) and was treated with radiotherapy alone to 45 Gy over 3 weeks at 3 Gy/fraction (ACRT). The second cohort (29 patients) had significantly better prognostic factors (KPS ≥70 and WL ≤5%) and was treated to 60–66 Gy over 6 to 6 weeks at 2 Gy per fraction (STRT) during the same period.

Results: In the first cohort treated by ACRT, the distribution of patients by AJCC stage was IIB 8%, IIIA 19%, and IIIB 73%. Sixty-two percent had KPS <70, and 76% had a WL of >5%. The maximum response rate as determined by chest X-ray was 60% among 45 of 55 patients who were evaluable for response: combined complete responses (20%) and partial responses (40%). Overall survival in these patients was 13% at 2 and 5 years, with a locoregional control rate of 42% and a freedom from distant metastasis rate of 54%. The ACRT cohort treated with 3 Gy per fraction had significantly lower KPS scores (p = 0.003) and greater WL (p = 0.063) than the cohort STRT treated with 2 Gy per fraction. However, treatment results and toxicity were not significantly different between the two cohorts in spite of significantly better prognostic factors in the STRT cohort.

Conclusions: Despite having worse prognostic factors, the cohort treated with radiotherapy alone to 45 Gy at 3 Gy per fraction over 3 weeks (ACRT) had response rates, locoregional control, and overall survival comparable to those in the cohort treated by a total dose of 60–66 Gy at 2 Gy per fraction over 6 to 6 weeks (STRT). Given that accelerated treatment schedules decrease treatment time and cost less, these may, in the current health care environment, be important factors for health care providers to consider in treating patients who have locally advanced NSCLC and borderline poor prognostic factors.  相似文献   


14.
: To assess the success of external beam radiation treatment in the management of loc-regional recurrence of rectosigmoid cancer.

: A retrospective analysis f 135 patients with locally recurrent rectosigmid cancer presenting to Peter MacCallum Cancer Institute between january 1981 and December 1990 was undertaken. Patients were treated with three different dose ranges of radiotherapy: 50–60 Gy (“Radical” group), 45 Gy (“High-dose palliative” group), and <45 Gy (“Low-dose palliative” group). Symptomatic response rates and overall survival for each group were determined.

: Symptomatic response rates of 85, 81, and 56% were achieved in the radical, high-dose palliative, and low-dose palliative groups, respectively. Estimated median survival times were 17.9, 14.8, and 9.1 months for the radical, high-dose palliative, and low-dose palliative groups, respectively.  相似文献   


15.
: To conduct a dose escalation clinical study with topotecan and concurrent standard dose thoracic irradiation to assess its feasibility and toxicity in the treatment of patients with locally advanced, inoperable nonsmall cell lung cancer (NSCLCA).

: Between April 1993 and August 1994, 12 patients with inoperable, loco-regionally advanced NSCLCA were entered in a prospective dose escalation trial and assigned to receive concurrent thoracic radiotherapy and topotecan. Patients received thoracic irradiation to a total tumor dose of 60 Gy in 30 fractions. Initial fields were to encompass the gross disease plus the mediastinum. Topotecan was delivered by bolus injection days 1 through 5, and days 22 through 26, beginning on the same day as the radiation therapy. The initial dose level was 0.5 mg/m2. Two additional dose levels of 0.75 mg/m2 and 1.0 mg/m2 were tested.

: Six patients were accessioned to the 0.5 mg/m2 dose level, three patients to the 0.75 mg/m2 dose level, and three patients to the 1.0 mg/m2 dose level. At the 0.5 mg/m2 dose level, zero of six patients had ≥Grade 4 hematologic toxicity. One of the six had Grade 3 esophagitis. At the 0.75 mg/m2 dose level, two of three patients had ≥Grade 3 nonhematologic toxicity including anorexia, fatigue, nausea, vomiting, and weakness; zero patients experienced ≥Grade 4 hematologic toxicity. At the 1.0 mg/m2 dose level one of three patients had ≥Grade 3 esophagitis, and two of three patients experienced Grade 4 neutropenia. With a follow-up of 12 to 24 months, two patients are alive and free of disease, three patients are alive with disease (two with distant metastasis, one with local disease and distant metastasis), and the remaining seven patients are dead of disease.

: The combination of topotecan and thoracic radiotherapy for nonsmall lung cancer, in the manner given by this protocol, could be safely given at a dose level of only 0.5 mg/m2 days 1 to 5 and 22 to 26 with 60 Gy of external beam radiotherapy. Higher doses of topotecan were associated with high hematologic and gastrointestinal toxicity. Distant metastasis was the primary pattern of failure.  相似文献   


16.
: 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.  相似文献   


17.
: To established an optimum fractionation for medium dose rate (MDR) brachytherapy from retrospective data of patients treated with different MDR schedules in comparison with a low dose rate (LDR) schedule.

: The study population consists of consecutive Stage IB-IIA-IIB patients who received radiotherapy alone with full dose brachytherapy plus external beam pelvic and parametrial irradiation from 1986–1993. Patients also receiving surgery or chemotherapy were excluded. The LDR group (n = 102, median follow-up: 80 months) received a median dose to Point A of 32.5 Gy fractions at 0.44 Gy/h plus 18 Gy of external whole pelvic irradiation. The MDR1 group (n = 30, median follow-up: 45 months) received a mean dose of two 32 Gy fractions at 1.68 Gy/h. An individual dose reduction of 12.5% was planned for this group according to the Manchester experience, but only a 4.8% dose reduction was achieved. The MDR2 group (n = 10, median follow-up: 36 months) received a dose of two 24 Gy fractions at 1.65 Gy/h. The MDR3 group (n = 10, median follow-up 33 months_ received a mean dose of three 15.3 Gy fractions at 1.64 Gy/h. And finally, the MDR4 group (n = 38, median follow-up: 24 months)_received six six 7.7 Gy fractions from two pulses 6 h apart in each of three insertions at 1.61 Gy/h/ The median external pelvic dose to MDR schedules was between 12 and 20 Gy. The linear quadratic (LQ) formula was used to calculate the biologically effective dose (BED) to tumor (BED) to tumor (Gy10) and rectum (Gy3), assuming T1/2 for REPAIR = 1.5 h.

: The crude central recurrence rate was 6% for LDR (mean BED - 95.4 Gy10) and 10% for MDR4 (mean BED = 77.0 Gy10 (p = NS). The remaining MDR groups had no recurrences. Grade 2 and 3 rectal or bladder complications were 0% for LDR (rectal BED = 109 Gy3), 83% for MDR1 (BED = 206 Gy3), and 30% for MDR3 (BED = 127 Gy3). The MDR2 and MDR4 groups presented no complications (BED, 123 Gy3, and 105 Gy3, respectively). The LQ formula appears to correlate with late complications of the different MDR regimens. A BED above 125 Gy3 was associated with Grade 2+3 rectal complications. Adequate central tumor control may be compromised with a tumor BED below 90–95 Gy10.

: Medium dose rate brachytherapy at 1.6 Gy/h to point A has a marked dose ratre effect. Increased fractionation is the cost of overcoming the less favorable therapeutic ratio for MDR than for LDR. A larger (25%) reduction of brachytherapy dose than previously reported is also necessary. Our most recently developed schedule for Stage I–II patients is three insertions on three treatment days with six 8.0 Gy brachytherapy fractions, two on each treatment day, following or preceding an external whole pelvis dose of 18 Gy, and followed by additional external parametrial dose.  相似文献   


18.
19.
Gamma Knife (GK) radiosurgery has recently been employed in patients with numerous brain metastases (METs), even those with 10 or more lesions. However, cumulative irradiation doses to the whole brain (WB), with such treatment, have not been determined.

Since the GammaPlan ver. 5.10 (ver. 5.31 is presently available, Leksell GammaPlan) became available in November 1998, 92 GK procedures have been performed for 80 patients with 10 or more brain METs at our facility. The median lesion number was 17 (range: 10–43) and the median cumulative volume of all tumors was 8.02 cc (range: 0.46–81.41 cc). The median selected dose at the lesion periphery was 20 Gy (range: 12–25 Gy). Based on these treatment protocols, the cumulative irradiation dose was computed.

The median cumulative irradiation dose to the WB was 4.71 (range: 2.16–8.51) Gy. The median brain volumes receiving >2 Gy, >5 Gy, >10 Gy, >15 Gy, and >20 Gy were 1105 (range 410–1501) cc, 309 (46–1247) cc, 64 (13–282) cc, 24 (2–77) cc, and 8 (0–40) cc, respectively.

The cumulative WB irradiation doses for patients with numerous radiosurgical targets were not considered to exceed the threshold level of normal brain necrosis.  相似文献   


20.
: 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.  相似文献   


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