Does Change in the Effect of Source Strength of the High Dose Rate sup192/supIridium Radio-Isotope on Local Control and Late Normal Tissue Toxicity (Bladder and Rectum) in the Treatment of Carcinoma Cervix

摘要

Aim: To analyse and assess the effect of dose rate of 192ir-source strength on late complications and local control rate during treatment of carcinoma cervix. Materials and Methods: One hundred and two cases of carcinoma cervix were included in the study. All patients were treated with a curative intent with radical dose of radiation as per the department protocol. All patients were treated with both EBRT plus Brachytherapy with Inj. Cisplatin 40 mg/m2 weekly. Patients were divided into 2 groups based on activity i.e. group A (10-6Ci) and group B (5-2Ci). After brachytherapy, point doses were analysed based on ICRU 38 recommendations. During follow up, morbidities were evaluated using RTOG grading system. Results: There was no difference in local control and distant metastasis in both groups after six months of follow up. Late Complications were comparable in both groups irrespective of source strength. Bladder complications were minimal with no significant difference in both study groups. Further Patients were divided into four groups i.e. BED of ICRU rectal point (3 and ≥100 Gy3) and source strength (10-6Ci and 5-2Ci), when BED was >100 Gy3 resulted in higher late rectal complication rate (P 3. Conclusion: This study suggests that change in source activity did not make a difference in local control, late rectal and bladder morbidities at 6 months of follow up. Longer follow up is required to assess long term results and morbidities.