Abstract

Aim: Radiation induced apoptosis has been shown in various animal experiments and cell culture assays. Although the exact mechanism of spontaneous or radiation induced apoptosis has not been fully understood yet. It is clear that radiation effects by inducing apoptosis. The cases presenting with rapidly increasing apoptotic index in the early course of radiotherapy may be more radiosensitive. The aim of this study was to investigate the changes in apoptotic index during the early course of radiotherapy and its relation with the response to treatment in patients with inoperable carcinoma of the uterine cervix. Methods: Punch biopsy specimens were obtained from 10 patients with stage IIB ceruix carcinoma receiving definitive radiotherapy prior to radiotherapy and after 9 Gy, and apoptosis was determined using immunhistochemical staining of bcl-2 proteins. Results: Median age of the patients vuas 47 (range 40-77). Brachytherapy was also applied to 7 patients and 3 patients received only external radiotherapy due to poor tumor response. Five patients with good performance status and renal functions received concurrent cisplatin 40 mg 2. During a median follow-up duration of 38 months (10- 53 months) two patients developed distant metastasis and one developed local recurrence at the 3rd, 17th and 21st months respectively and these patients were lost due to disease progression Bcl-2 staining was detected in pretreatment specimens of 9 patients. Apoptotic index was defined as (+) or (++) according to staining density (higher and lover than 33%). Staining density decreased in 3 patients following 9 Gy when compared with the pretreatment staining density. No change of staining density was noted in 6 patients. The correlation between the pretreatment staining pattern and disease progression was weak. The prognosis of patients with high density staining was worse than patients with lovu density staining or no staining (p: 0. 3, r: 0. 37). Conclusion: To increase our knowledge about the radiobiology or molecular biology of cervix cancer will help to improve new treatment approaches. The prognosis is different even in tumors with identical stage and histology and it is mandatory to define radiosensitive or radio resistant subgroups in order to achieve better treatment results. In this study changes of bcl-2 apoptotic index during radiotherapy did not help to predict the radio sensitivity of cervix cancer. Further studies on this topic with larger patient populations are needed.