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We examined the best way to combine recently developed radiofrequency intracavitary hyperthermia with simultaneous high dose-rate intracavitary brachytherapy in an original experimental model. Temperature distribution was measured with an experimental phantom which was immersed in a water bath with the temperature controlled at 37 degrees C. Radiation dose distribution was calculated with a treatment-planning computer. Cell survival was measured by colony assay with HeLa-TG cells in vitro. Radiation dose response at 1 - 7 Gy and time response with hyperthermia in the range of 40 - 46 degrees C were estimated. Radiation dose-response curves in simultaneous treatment with hyperthermia for 30 min at 37 to 46 degrees C were estimated and the surviving fractions in combined treatment were plotted against temperature. For intracavitary radiation alone, cell survival rates increased with increasing distance from the source. For intracavitary hyperthermia alone, the maximum temperature was observed at a depth of 13 mm from the surface of the applicator under suitable treatment conditions. Homogeneous cell killing from the surface of the applicator to a tumor depth of 13 mm was observed under a specific treatment condition. Our experimental model is useful for evaluating the best simultaneous combined treatment.

Background: As the human society grows more aged, it is considered important to elucidate factors essential in applying radical radiotherapy (RT) to the elderly, with ages as high as 90 years and greater., Methods: A retrospective survey was conducted for patients 90 years of age or older who received radiotherapy with radical intent in eight leading institutions in Japan from 1990 through 1995., Results: Fifty-seven nonagenarian patients were studied. Their ages ranged up to 98 (median 91) and there was a strong female preponderance (M/F: 16/41). The distribution by site was as follows: head and neck, 16; skin and adnexae, 11; uterine cervix, 7; esophagus, 6. The prevailing histopathological diagnosis was squamous cell carcinoma (34), followed by adenocarcinomas (8). The highest age at RT was 98 years [female, skin cancer, died of senility 2.5 years after treatment, with no evidence of disease (NED)] and the longest survivor is 102 years old (female, glottic cancer T2, age at RT 93, alive NED for 8 years, uses wheel-chair). The rate of completion of treatment was 75% (43/57), if the treatment field was limited to the gross primary tumor volume only and if the cumulative dose was above 80% of the tolerable adult dose. Familial escort was necessary for most of the patients in completing the day-to-day RT., Conclusion: Radiotherapy is feasible with radical intent even in the elderly, if the treatment field is limited to the gross primary tumor volume only, if the cumulative dose is above 80% of the tolerable adult dose and if familial support is adequate.

Purpose: To investigate the clinical efficacy of radiation therapy for cancer in patients aged 90 years or older., Materials and Methods: Cancer cases in 32 patients (11 men, 21 women) aged 90 years or older who underwent radiation therapy in 1970-1997 were retrospectively analyzed. The mean patient age was 92.2 years, with a range of 90-98 years. Head and neck cancer (n = 14 [44%]) and skin cancer (n = 6 [19%]) were the most common., Results: Eleven (79%) of the 14 patients with head and neck cancer were treated with curative intent. Radiation response without any severe complication was observed in nine (90%) of the 10 patients with head and neck cancer treated with curative intent who finished treatment. The median survival time was 8 months (range, 3-55 months) in the 10 patients with head and neck cancer who completed treatment with curative intent. Complete response was achieved in all of the patients with skin cancer without any major sequelae. Complete response was also observed in all three of the patients with non-Hodgkin lymphoma, but two patients treated with adjuvant chemotherapy died of drug-induced pneumonitis. Palliation was achieved in all nine of the patients treated with palliative intent., Conclusion: Age of 90 years or older is not a limiting factor for radiation therapy.

Relationships between radiation-induced apoptosis and oncogenes or suppressor genes (p53, MDM2, c-myc, p21ras and bcl-2) were immunohistochemically studied in 7 human tumors transplanted to nude mice. The most radiosensitive ependymoblastoma was negative for p53 and c-myc, however, the other 6 tumors were positive for them. Following irradiation, the ependymoblastoma became p53 positive, and showed the highest incidence of apoptosis among the 7 tumors. In addition, bcl-2 expression in this tumor was slightly different from that in the others.

The effects of radiation on tumors should be divided into radiosensitivity and radioresponsiveness. The local effects of radiation are not always consistent with curability. Though local control is one requirement to attain cure, the primary factor that affects long-term survival is the natural history of the tumor. The effects of irradiation can not be predicted only by determining the histological type of tumor. However, the natural history of the tumor can be understood by careful observation of the stroma in the tumor and condition of the host. As the result, radiocurability can be predicted to some extent.

The present status of clinical application and future prospect of immunotherapy using BRMs, especially PS-K, for cancer patients treated by irradiation were described here. Prolonged survivals were revealed in the radiation therapy of patients with carcinoma of lung and uterine cervix concomitant use of PS-K. And the condition necessary for long-term survival with BRMs were thought to be that the tumor was almost disappeared by irradiation. But, there is not an evaluation criteria for BRMs without any direct effects on tumor. Then judgment of clinical usefulness of immunopotentiators are difficult and needs to make new evaluation criteria.

The effects of radiotherapy were evaluated according to the aim of treatment in 526 patients with malignant tumors. All of them underwent medical examination and were treated by irradiation for the first time in the Department of Radiology, Gunma University Hospital, in 1977 and 1978. They were divided into five groups according to the aim of treatment, which was established before the start of radiotherapy and based on curability. Groups A, B, and C (radical radiotherapy) were composed of patients with localized tumors, and Group D (palliative radiotherapy) of those with advanced or recurrent tumors. The relative five-year survival rate was 107% in Group A (110 patients), 67% in Group B (85 patients),a nd 34% in Group C (151 patients), or 66% in all patients treated radically. The cumulative 24-month survival rate was 16% in Group D (159 patients). In 21 patients treated symptomatically (Group E), the rate of effectiveness of radiotherapy was 71%. In the 526 patients as a whole, the relative five-year survival rate was 46%. We were relatively satisfied with these results, but believe that much more favorable results will be obtained in the near future if a more suitable method of individual treatment for each patient with malignant tumor can be devised.