Early outcomes of abbreviated multi-fractionated brachytherapy schedule for cervix cancer during COVID-19 pandemic.

ABSTRACT

PURPOSE: Brachytherapy (BT) for cervix cancer was listed as a level I priority and reduced number of implants and multiple fractions were recommended during COVID-19 pandemic. We present early clinical outcome of this approach. METHODS AND MATERIALS Patients treated with (chemo)radiotherapy and BT with single implant and multiple fractions BT were included. Treatment protocol included 3-5 fractions of 5-8.5 Gy with an aim to achieve point A dose of 70 Gy EQD210Gy (or HRCTV dose of >80 Gy EQD210Gy) in those undergoing intracavitary (IC) and HRCTV dose >85 Gy EQD2 10Gy in patients undergoing Intracavitary-Interstitial (IC/IS) whereas maintaining bladder (B2cc), rectum (R2cc), sigmoid (S 2cc) doses of 90, 75, and 75 Gy EQD23Gy. Time to event analysis was used to report oncological endpoints. Toxicity was reported using crude proportions. RESULTS: From April 2020 to March, 2021, 64 patients with stage IB2-IV received single implant and multi-fraction BT after external radiation of 45 Gy/25 fractions/5 weeks. Only 76.7% (n = 49) received concurrent chemotherapy. Median overall treatment time (OTT) was 56 days (38-131 days). Overall, 62.5% (n = 40) patients received IC and 37.5% (n = 24) received IC+IS. The median HRCTV was 34.7 cc (IQR 25-41). Median (IQR) point A dose, HRCTV D90, B2cc, R2cc, and S2cc for those undergoing IC was 74 Gy (71-78), 80 Gy (73-84), 86 Gy (82-89), 70 Gy (65-74), 65 Gy (59-73) respectively. For the IC+IS cohort, HRCTV D90, B2cc, R2cc, and S2cc was 84 Gy (78-89 Gy), 89 Gy (86-92), 70 Gy (67-74), 68 Gy (59-76). At a median follow-up of 16 months (5-27) the 2-year local control, pelvic control, cause specific and overall survival was 88%, 85.3%, 92.2%, and 81.3% respectively. Late gastrointestinal and genitourinary grade ≥III toxicities were 14% and 1.5% each. CONCLUSIONS: Abbreviated BT outcomes are encouraging for oncological outcomes despite delays in overall treatment time and omission of chemotherapy. Further mature follow up is needed.