When cells are exposed to low doses of a mutagenic or clastogenic agents, they often become less sensitive to the effects of a higher does administered subsequently. Such adaptive responses were first described in Escherichia coli and mammalian cells to low doses of an alkylating agent. Since most of the studies have been carried out with human lymphocytes, it is urgently...

Hypothesis that hypoxic tumors should be more responsive to the addition of preferential hypoxic cell cytotoxin SR 4233 (tirapazamine) to fractionated irradiation was tested in the mouse SCCVII carcinoma and RIF-1 sarcoma, Model of hypoxic tumor was established using the tumor bed effect; tumors growing in the preirradiated tissue (preirradiated tumors) were more hypoxic than tumors growing in the unirradiated...

We evaluated the effect of nicotinamide on cellular O2 consumption and metabolic status i.e., adenylate phosphates and NAD+ in-vitro, and changes in blood flow in-vivo, to determine whether changes in cellular metabolism or increased oxygen availability, was responsible for increased tumor oxygenation. Thirty min. Pre-incubation of cells with~4mM (=500mg/kg) nicotinamide resulted in no change in cellular O2 consumption. Similarly, neither...

There are a number of reports suggesting that there may be a correlation between the clinical response to radiotherapy in various tumors and the clonogenic survival of cell lines derived from these tumor following exposure to 2 Gy (SF2). Authors conducted this study to determine SF2 for cells in primary culture from surgical specimens. The tumor tissues with squamous cell carcinoma...

From 1982 to 1991, sixteen patients with primary on-Hodgkin's lymphoma of the central nervous system (CNS) were seen at Kyung Hee University Hospital. The most common subtypes were large, noncleaved cell lymphoma and immunoblastic lymphoma of B cells. Lesions most commolnly involved were the parietal lobes and/or deep nuclei. Positive cerebrospinal fluid cytology was rare at initial presentation. Sixteen patients were...

A retrospective analysis was performed on 55 patients with malignant parotid tumor who were treated with radiation therapy between March, 1979 and July, 1989. Of these patients, 8 patients received radiation therapy(RT) alone and 47 patients were treated with combined operation and radiation therapy(OP+RT). The follow-up period of the survivors ranged form 1 to 129 months with a median of...

Seventy-nine patients with carcinoma of maxillary antrum treated at the department of therapeutic radiology, Kosin Medical Center, between June 1980 and December 1986 were analyzed retrospectively for survival rate and treatment failure. Forty-three patients were treated with radiotherapy alone and thirty-six patients were treated with combination of surgery and radiotherapy. The overall 5 year survival rate was 32%, patients that...

Seventy-five patients with tumors of the head and neck treated with either radiation therapy alone or combined with surgery or chemotherapy were studied prospectively to evaluate the effects of radiation therapy to the neck on thyroid gland between September 1986 and October 1992. All patients were serially monitored for thyroid function tests before and after radiation therapy. Radiation dose to...

Kimura's disease is a rare disorder which predominantly involves the head and neck region can cause eosinophilia in peripheral blood. It has beeb treated with steroids, surgical excision, irradiation, cryotherapy, and laser. The sessions have a tendency to recur after steroid and surgery. We reviewed 2 patients with Kimura's disease who recurred, because they were resistant steroid therapy and surgery, and...

From December 1989 to February 1993, 108 patients with Non-Small Cell Lung Cancers(NSCLC) were studied retrospectively to evaluate radiotherapeutic significance of serum levels of NSE. We considered elevated serum neuron specific pathologic evaluation revealed 86 squamous cell carcinomas, 11 adenocarcinomas, 3 large cell carcinomas, 3 mucoepidermoid carcinomas, and 5 unknown pathology. Eight patients had stageI, 40 stage III A, and...

PURPOSE: The aim of this study is to analyze the clinical results of thermo-irradiation treatment for surgically unresectable advanced hepatoma with or without hepatic arterial chemo-embolization (HACE), chemotherapy (CT) and interferon (IFN) therapy. MATERIALS AND METHODS: Between February 1990 and December 1992, 45 patients with surgically unresectable advanced hepatomas were treated by thermo-irradiation with or without hepatic arterial chemo-embolization and other...

PURPOSE: Despite apparently complete resection of cancer of the rectum, local recurrence rate was high. Radiation therapy has been used either alone or in combination with chemotherapy as an adjunct to surgery to reduce the risk of recurrence. This study was designed to evaluate the prognostic factors, survival rate and local recurrence rate of the rectal cancer who had received...

Among the 63 patients with histopathologically proven primary squamous cell anal cancer who were managed in Presbyterian Medical Center and Yonsei University Cancer from Jan. 1971 to Dec. 1991, 34 patients, who were managed with surgery alone (abdominoperineal resection) or post-operative radiotherapy and concurrent chemoradiotherapy were analyzed. With mean follow up time of 81.3 months, 30 patients (88%) were followed...

The purpose of this paper is to develop an efficient method for the quick determination of multiple isocenters plans to provide optimal dose distribution in stereotactic radiosurgery. A Spherical dose model was developed through the use of fit to the exact dose data calculated in a 18cm diameter of spherical head phantom. It computes dose quickly for each spherical part...

In spite of remarkable improvement of surgical skills and anesthesia, local failure still occurred in 36-45% of locally advanced colorectal cancer after curative resection with or without pre-or post-operative irradiation. Intraoperative radiation therapy (IORT) is the ideal modality which respectable lesions are removed surgically and the remaining cancer nests are sterilized by irradiation during a surgical procedure. Therefore, the excellent local...