Five-fraction HDR brachytherapy in locally advanced cervical cancer: A monocentric experience

Abstract

Purpose: The 5-fraction scheme (5×5-5.5Gy) is a common High-Dose Rate (HDR) intracavitary brachytherapy regimen for locally advanced cervical cancer (LACC). Yet, its equivalence with Pulse-Dose rate (PDR) schemes remains unproved. The present study aimed at reporting on the outcome of LACC patients treated with 5-fraction HDR brachytherapy.

Materials and methods: The medical records of all consecutive patients treated with curative-intent HDR brachytherapy for a LACC in a French Cancer Center were retrospectively reviewed.

Results: Thirty-eight LACC patients underwent a 5-fraction intracavitary HDR brachytherapy between 2015 and 2019 (median dose=25Gy/5 fractions, following external-beam radiotherapy). Median age at diagnosis was 60 (range: 29-87). Thirty-one patients (81.5%) underwent concurrent chemotherapy. Tumor stages ranged from 3 IB2 (7.8%), 4 IB3 (10.5%), 4 IIA2 (10.5%), 12 IIB (31.7%), 1 IIIA (2.6%), 2 IIIB (5.3%), 7 IIIC1 (18.5%), 4 IIIC2 (10.5%), 1 IVA (2.6%) (2018 FIGO). Median D90% to CTV_HR reached 79.5Gy (EQD2). Median D90% to CTV_IR reached 59.5Gy (EQD2). Median Bladder D2cc was 69.8Gy (EQD2). Median Rectum D2cc was 58.3Gy (EQD2). Acute/late grade 3 toxicity was reported in one patient (2.6%). No grade 4-5 toxicity occurred. At a median 38 months follow-up, 10 patients (26.3%) had local (n=7, 18.4%), nodal (n=6, 15.7%) and/or distant (n=7, 18.4%) relapse. Three-year overall survival rate was of 81.6%.

Conclusion: The 5-fraction HDR scheme was well tolerated even in frail patients. Three-year local control was lower than expected. Treatment (absence of parametrial interstitial implants and use of cervical EBRT boost) and patients' characteristics (age, comorbidities) may explain such results.

Keywords: Brachytherapy; Cancer du col de l’utérus; Cervical cancer; Chemotherapy; Chimiothérapie; Curiethérapie; Débit de dose élevé; High-dose rate; Radiotherapy; Radiothérapie.