Chronicles of hyperthermia oncology, especially differential cellular thermosensitivities based on the heating temperature, cell phase response to heating under given condition, hyperthermic modification of radiosensitivities of cells and tissues, heat shock proteins as a part of physiological stress proteins etc were reviewed.

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In therapy of lung cancer it is important to be decided what type of therapeutic strategy is most appropriate and what kind of results can be anticipated. Selection of type of therapy in primary lung cancer depends on the following factors: Histological type, Location and Stage.
The differences of methodology, which is necessary in deciding therapeutic strategy, employed to diagnose and evaluate cases which are X-ray-negative and sputum cytology-positive (roentgenologically occult lung cancer) and cases which reveal abnormal findings on chest X-ray are described. Especially in occult lung cancer cases, with the remarkable improvements that have been made in the fiberoptic bronchoscope, bronchoscopy has become relatively simple to perform and is extremely effective for detailed examination as far as 4th order bronchi for tumor localization.
Surgery treatment is the treatment of choise for lung cancer. Until 1960s, pneumonectomy was a common surgical method for lung cancer, but after that period lobectomy and systemic mediastinal lymph node dissection bacame standard. As for the survical rate according to pathological stage, out of a total of 1, 211 resected cases, among stage I and II cases in which the surgical procedure was thought to be curative, the 5-year survival rate were 67.4% and 41.1%, respectively. The 5-year survival rates of stage IIIA and IIIB, on the other hand, were only 14.7% and 0% respectively. In order to improve the survival rate of lung cancer, more efforts must be made for early detection of early stage lung cancer cases, and the development of more effective adjuvant therapy is anticipated.

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The purpose of this study was to determine the relationship between tumor control dose (TCD) and the number of cells for non-palpable (microscopic) tumors. The tumor-bearing legs of BDF₁ mice were irradiated locally within 4 days after implantation of Lewis lung carcinoma. The number of viable cells at the time of irradiation was estimated from the number of implanted cells and the mean doubling time of cells during the microscopic phase. The mean doubling time of 0.91 days was calculated from the growth times to reach a volume of 100 mm³ when a varying number of cells was implanted. The number of viable tumor cells eradicable at a tumor control dose at a 50% or 14%(1/7) level depended strongly upon radiation dose (radiosensitive phase) up to 10⁵ cells, but was weak (radioresistant phase) for over 10⁵cells: the TCD⁵⁰s were 12 Gy for 10⁵ viable tumor cells and 36 Gy for 10⁶ cells. It was suggested that radioresistance developed with the increasing number of cells in the microscopic tumors. Combination with a hypoxic radiosensitizer, RP-170, enhanced tumor control rates for the radioresistant tumors.
In conclusion, tumor control rates were remarkably reduced by the presence of radioresistant cells, including hypoxic cells in the microscopic tumors containing a large number of cells. The hypoxic radiosensitizer would be of value for such microscopic tumors.

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Factors considered to influence local control of esophageal squamous cell carcinoma treated with radiotherapy were analyzed retrospectively using multivariate method. This study involved 65 patients who had received more than 60 Gy between 1982 and 1990 at Niigata University Hospital.
There were 22 cases with locally controlled lesions at the time of analysis. The two-year local control rate was 32%. Factors studied for the analysis included sex, age, performance status, tumor location, radiologic type, T-stage, tumor volume, tumor length, radiation dose, and type of chemotherapy.
As a result, radiologic type, T-stage, tumor location and age were considered to be important to predict local control. Tumor volume did not influence local control significantly. In patients with radiographically ulcerative and localized type lesions, however, tumors with a volume of greater than 80cm³ failed more frequently than those with less than 80cm³. It is suggested that tumor volume can predict local control in such cases.

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From 1972 to 1992, 15 patients with medulloblastoma have been treated with surgery and post-operative radiotherapy. Whole central nervous system (CNS) irradiation followed by boost to posterior fossa was used as a standard treatment. Various dose schedules were used. The 5 and 10 years disease free survival was 43% and 33%, respectively. In 7 patients who received grossly total resection and radiotherapy, only one patient relapsed 106 months after treatment. All of 8 patients who received partial resection or biopsy followed by radiotherapy have died with the median survival of 16 months. Diagnostic procedures, total dose of radiation to the posterior fossa, and technical factors of whole CNS irradiation were suggested to be prognostic factors. Mental retardation was observed in two patients who received whole brain irradiation of 35Gy. Five out of 6 patients who survived more than 3 years experienced growth retardation.

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A treatment planning on a small lung cancer has been made for the multi-portal irradiations of narrow proton beams and compared with that for 4MV X-ray beams. The low dose tails with those incident beams are visible for X-rays, while these are below the explicit dose level and not visible for proton beams. Further difference is noticed between these two dose distributions at the high dose peaks. For the proton irradiations, the flat high dose peak of 1cm width with 5mm marginal region covers the target, while for X-rays the peak of Gaussian distribution reaches 100% dose level only just for 2cm field beams. This suggests the target can be covered well by use of the broader X-ray beams followed by increase in DVH at the surrounding normal tissue.

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Between December 1990 and November 1993, 21 cases of squamous cell carcinoam of the oral region were treated with twice-a-day irradiation (1.2 Gy/fraction, 4-hour interfraction interval). Ten of the patients had T4 tumors. Seventeen patients received irradiation alone to the primary site. The total dose administered was 70.8-74.4 Gy in the majority of cases. In all cases except one, the treatment was completed without a rest interval. Local control results at two years and the time of assessment were 1/2 and 1/2 for T1 tumors, 4/6 and 5/8 for T2 tumors, 0/1 and 0/1 for T3 tumors and 1/7 and 2/10 for T4 tumors. T stage was a significant prognostic factor for local control (p=0.007). The local control rate did not correlate well with the total dose (P=0.103). Only one pathologic fracture of the mandible was observed as a complication. It was considered that this treatment regimen was preferable for T1 and T2 tumors in respect of local control but was not sufficient for T3 and T4 tumors.

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