Lymphocyte radiosensitivity is a significant prognostic factor for morbidity in carcinoma of the cervix

Purpose: To study the relationship between pretreatment peripheral blood ly mphocyte radiosensitivity and morbidity following radiation therapy. Methods and Materials: A prospective study was carried out in which patient s with carcinoma of the cervix underwent radiation therapy. Intrinsic radio sensitivity was measured on pretreatment peripheral blood lymphocytes, usin g a limiting dilution clonogenic assay. Late morbidity was assessed using t he Franco-Italian glossary. Results were correlated in an actuarial analysi s. Results: There were no correlations between the measured lymphocyte radiose nsitivity (SF2) and colony-forming efficiency, patient age, tumor grade, or disease stage. For 83 patients, lymphocyte SF2 was a significant prognosti c factor for the probability of developing both any (p = 0.002) and Grade 3 (p = 0.026) morbidity. In 174 patients, stage showed borderline significan ce as a prognostic factor for morbidity (p = 0.056). However, the type of t reatment (intracavitary alone, intracavitary plus parametrial irradiation, single insertion plus whole-pelvis irradiation) was significantly associate d with the probability of developing late complications (p = 0.013). There was a weak significant inverse correlation between lymphocyte SF2 and grade of morbidity (r = -0.34, p 0.002). Conclusion: These data highlight the importance of normal cell radiosensiti vity as a factor determining radiation therapy response. They also show tha t peripheral blood lymphocyte SF2 is a highly significant prognostic factor for the probability of developing late radiation morbidity, and that carci noma of the cervix is a good model for testing radiobiologic principles in the clinic. (C) 2001 Elsevier Science Inc.