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PURPOSE: We compare general and disease specific health related quality of life in men undergoing brachytherapy for early stage prostate cancer to those undergoing radical prostatectomy and age matched healthy controls. MATERIALS AND METHODS: Cohorts consisted of 48 men treated with brachytherapy with and without pretreatment external beam radiation therapy (brachytherapy group), 74 who underwent radical prostatectomy (prostatectomy group) and age matched healthy controls from the literature. The RAND 36-item general health survey, University of California Los Angeles Prostate Cancer Index, American Urological Association symptom index, validated Cancer Interference with Life and Family Scales, and sociodemographic and co-morbidity questionnaires were completed 3 to 17 months after treatment. RESULTS: General health related quality of life did not differ greatly among the 3 groups. Urinary function (leakage) was worse in the brachytherapy group than in controls but better than in the prostatectomy group. Brachytherapy group patients had more irritative urinary symptoms and worse bowel function than controls. Sexual function and bother were worse in prostatectomy and brachytherapy groups than in healthy controls. Physical function, bodily pain, urinary function, and bother and American Urological Association symptom index scores improved with time after brachytherapy. Patients who underwent brachytherapy after external beam radiation performed worse in all general and disease specific health related quality of life domains compared to those who did not undergo pretreatment radiation therapy. CONCLUSIONS: At an average of 7.5 months after treatment the general health related quality of life of patients undergoing brachytherapy with and without pretreatment external beam radiation was similar to age matched controls, although urinary, bowel and sexual problems were reported. These problems appeared to improve during the first year after treatment. Much of the impairment in disease specific health related quality of life among patients undergoing brachytherapy may be attributed to pretreatment radiation.

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PURPOSE: To evaluate the Monte Carlo code MCNP4B for low-energy brachytherapy calculations, including the effects of interseed attenuation and patient specific heterogeneities, on the calculated dose distribution from transperineal implantation of 125I. METHODS AND MATERIALS: The Monte Carlo code MCNP4B was used to model and benchmark the absolute dose distribution from two 125I brachytherapy seeds (model 6711 and 6702). Based upon the physical source model, the total photon intensity and differential energy spectrum were evaluated as a function of angle from the transverse bisector of the source. These spectral and intensity data were reformatted to produce probability distributions for sampling from a virtual point source. The virtual source model and a modified version of MCNP4B is then used for simulating arbitrary brachytherapy source configurations within a homogeneous or heterogeneous patient specific computed tomography (CT)-based lattice geometry. RESULTS AND CONCLUSION: Comparison with TG-43 data and the Monte Carlo calculations is excellent with MCNP4B predicting the radial dose function for the 125I 6711 and 6702 sources within 6% for all data points tested. Attenuation effects from neighboring seeds were investigated for pre- and postimplant seed distributions and found to be negligible. Preliminary dosimetry analysis of postimplant seed distributions comparing homogeneous water versus heterogeneous CT simulation geometries indicates an average decrease of approximately 5.6% for the volume of tissue irradiated to a prescription isodose line of 144 Gy.

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PURPOSE: To evaluate the effectiveness of fast neutron radiation therapy in treatment of locally advanced carcinomas of the prostate. METHODS AND MATERIALS: From April 1986 to October 1990, 178 patients were entered on a prospective, multi-institutional randomized study of the NCI-sponsored Neutron Therapy Collaborative Working Group. This trial compared external beam photon irradiation (7000-7020 cGy) with external beam neutron irradiation (2040 ncGy) for patients with high-grade T2 or T3-4, N0-1, M0 adenocarcinomas of the prostate. Eighty-nine patients were randomized to each treatment. Six patients were subsequently judged to be ineligible, leaving 85 photon and 87 neutron randomized patients eligible for analysis. RESULTS: With a follow-up time ranging from 40 to 86 months (68 months median follow-up) the 5-year actuarial clinical local-regional failure rate for patients treated with neutrons was 11%, vs. 32% for photons (p < 0.01). Incorporating the results of routine posttreatment prostate biopsies, the resulting "histological" local-regional tumor failure rates were 13% for neutrons vs. 32% for photons (p = 0.01). To date, actuarial survival and cause-specific survival rates are statistically indistinguishable for the two patient cohorts, with 32% of the neutron-treated patient deaths and 41% of the photon-treated patient deaths caused by prostate cancer (p = n.s.). Prostate specific antigen (PSA) values were elevated in 17% of neutron-treated patients and 45% of photon-treated patients at 5 years (p < 0.001). Severe late complications of treatment were higher for the neutron-treated patients (11% vs. 3%), and were inversely correlated with the degree of neutron beam shaping available at the participating institutions. Neutron treatment delivery utilizing a fully rotational gantry and multileaf collimator did not result in an increase in severe late effects when compared to photon treatment. CONCLUSION: High energy fast neutron radiotherapy is safe and effective when adequate beam delivery systems and collimation are available, and it is significantly superior to external beam photon radiotherapy in the local-regional treatment of large prostate tumors.

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PURPOSE: To determine, with a prospective, multicenter randomized study, whether fast neutron radiation therapy improves the outcome for patients with non-small cell lung cancer, as compared to conventional photon radiotherapy. METHODS AND MATERIALS: From September 1986 to March 1991, a total of 200 patients with inoperable regional non-small cell lung cancer were randomized to 20.4 Gy in 12 fractions with neutrons versus 66 Gy in 33 fractions with photons. Inoperable patients with Radiation Therapy Oncology Group Stages I, II, III, or IV(M0) disease, Karnofsky Performance Score > or = 70, and who had received no previous therapy for their non-small cell lung cancer were eligible for the study. Of the 200 patients randomized, a total of 193 patients, 99 on the neutron arm and 94 on the photon arm, were eligible for analysis. The two treatment groups were balanced with regards to prognostic factors. At the time of this analysis, the median at-risk follow-up was 33 months, with a minimum follow-up of 16 months. RESULTS: No difference in overall survival was observed; however, there was a statistically significant improvement in survival for patients with squamous cell histology (p = 0.02), and a trend toward improved survival for those with favorable prognostic factors (i.e., patients who were not T4, N3, and had no pleural effusion or weight loss > 5% from baseline) (p = 0.15), favoring the neutron-treated group. With the exception of skin and subcutaneous changes, acute and late toxicity was similar in both arms. CONCLUSION: In selected patients with inoperable regional non-small cell lung cancer (e.g., squamous cell histology, favorable prognostic factors), fast neutron irradiation provides a therapeutic benefit over conventional photon radiotherapy.

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Heart and heart-lung xenografts are a potential solution to the shortage of donors. Concern over the adequacy of conventional immunosuppression in prevention of xenograft rejection, however, has hindered their use. Cyclosporine has not been successful in suppressing the rejection process in cardiac xenotransplantation, and other methods of immunosuppression need to be investigated. Therefore we studied the effect of preoperative total lymphoid irradiation (TLI) in combination with cyclosporine in a primate heart-lung xenograft model using cynomolgus monkey donors and baboon recipients. Heart-lung grafts were harvested from donors and transplanted orthotopically in baboons with use of cardiopulmonary bypass. Recipients were treated in one of three groups: (1) cyclosporine and steroids (controls), (2) cyclosporine and steroids plus TLI 20 Gy, or (3) cyclosporine, steroids, antithymocyte globulin, and TLI 6 Gy. Mean survival time of the baboons treated with cyclosporine and steroids was 8 +/- 0.6 days. The group receiving 20 Gy TLI had prohibitive perioperative mortality; however, one baboon lived an additional 90 days, and at autopsy the heart showed minimal rejection. Treatment with TLI at 6 Gy in combination with cyclosporine, antithymocyte globulin, and steroids comparatively prolonged survival (16 +/- 7.8 vs 8 +/- 0.6 days; p less than 0.001), and all animals in this group died of infection, with only minimal evidence of heart rejection noted in animals surviving 30 days. We conclude that the addition of TLI and antithymocyte globulin to cyclosporine-based standard immunosuppression is a potent immunosuppressant in heart-lung xenotransplantation; nevertheless, infection remains a common complication.

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Thirty patients found to have residual epithelial ovarian cancer at second-look laparotomy were treated with whole abdominal radiation as salvage therapy. Dosage fractions were 120 rad per day until 3000 rad were delivered, then the pelvis was boosted to 5000 rad at 180 rad per day. Fourteen patients (47%) completed therapy without interruption and seven (23%) completed therapy with interruptions due to myelosuppression ranging from one to four weeks. Therapy was not completed in nine patients (30%). Four of 16 patients (25%) with microscopic residual disease before radiation remain alive and free of disease at 22 to 41 months. Two of six (33%) patients with minimal (less than or equal to 5 mm) residual disease remain alive and free of disease 19 to 40 months after radiation treatment. Patients with residual nodules greater than 5 mm uniformly did poorly. Patients who progressed on primary chemotherapy had a median survival of seven months, compared with more than 38 months for chemotherapy responders. Chronic bowel morbidity was a significant problem, with 30% of patients surviving at least four months from completion of radiation requiring laparotomy for small bowel obstruction. These preliminary results suggest that whole abdominal radiation may be useful in the management of patients who have responded to primary chemotherapy, but the benefit is confined to those patients who have minimal or microscopic disease at second-look laparotomy.

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