THE RELATIONSHIP BETWEEN ROSE RATE, BED AND LOCAL CONTROL LATE COMPLICATIONS IN DEFINITIVE RADIOTHERAPY OF CERVICAL CARCINOMA

Between 1970-1999, 865 patients with stage I-IVA cervical carcinoma who were treated by definitive radiotherapy were analyzed retrospectively to evaluate the effects of treatment schedules and Biological Effective Doses (BED) on survival and late complications. Various treatment schedules were used during those years. Patients received external radiotherapy to whole pelvis (50.4-54 Gy / 5.5-6 weeks) with Co60 or linear accelerator. 774 (89%) patients were applied intracavitary brachytherapy of whom 114 (19%) with LDR and 630 (81%) with HDR. 91 patients received only external RT. BED were calculated by using linear quadratic formula in all patients. Median age of the patients was 52 years (22-89) Mean follow up was 40.64 ± 29.54 months. Stage, I-IIA 7.5%, IIB-IIIB were 86%, IVA 6.5%. Local disease free (LDFS) and overall survivals (OS) were 71%, 73%'un stage I-IIA, 67%, 61% in stage IIB, 52%, 43% in stage III, 28%,18% in stage IVA respectively. Treatment results were similar in LDR and HDR. LDFS and OS were 56%, 52% in LDR and 62%, 53% in HDR respectively. Local failure rates (LF) and LDFS were 41%, 53% in patients with BED10 <85 Gy and 37%, 62% in BED-10 >=85 Gy. Pretreatment factors associated with improved survival in univariate and multivariate analysis include lower stage, higher age and unilateral parametrial invasion and treatment factors include application of intracavitary brachytherapy and BED10 >=85 Gy. In all patients grade 3-4 urogenital system complications were 0.5%, gastrointestinal system complications were 1%. Grade 3-4 complications were similar in LDR and HDR. BED3 120 Gy and 140 Gy were evaluated for ürogenital and gastrointestinal complications and were found to be non-significant. In this study, we found significant effect of BED on treatment results. And we suggest that BED10 >85 Gy should be used in definitive radiotherapy in cervical carcinoma.

Keywords: brachtherapy, cervical carcinoma, bed