Abstract
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.
Highlights
Some components, such as multi-leveled equations, graphics, and tables are not prescribed, the various table text styles are Cancer of the cervix is the most common cancer in India [1]
The probable reason for such under reporting is due to variation in the fractionation schedules between various institutions.192Ir Radioisotope which is commonly used as HDR Brachytherapy source and has very short half-life of 78.3 days
When ICRU rectal point BED was analysed in 50 patients in group A, BED ranged from 85 Gy - 154 Gy3 and majority of patients BED was between 100 - 130 Gy3
Summary
Some components, such as multi-leveled equations, graphics, and tables are not prescribed, the various table text styles are Cancer of the cervix is the most common cancer in India [1]. External Beam Radiotherapy and Brachytherapy are widely practicing in many centers in the world as well as in India [2] [3]. Over the years the external beam radiotherapy has been well standardized and uniform but the brachytherapy component has experienced tremendous variation from LDR to HDR Intracavitary radiation therapy. While there are four decades of published literature on the efficacy of HDR brachytherapy over LDR brachytherapy, variation in fractionation schedules and its effect of change in dose rate on treatment outcome and normal tissue complications is well reported but very few reports on the effect of source strength of HDR brachytherapy on local control and late rectal and bladder morbidity is available. This study was undertaken to compare and understand the radiobiological relationships of Iridium source activity on local control and late rectal, bladder morbidities
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have