Objectives: A previous study has suggested the benefit of sub-renal vein radiotherapy (SRVRT) for pelvic lymph node (PLN)-positive cervical cancer. In order to better select patients for SRVRT, this study aimed to evaluate the value of a risk-based radiation field based on PLN location and number in PLN-positive cervical cancer.
Methods: We reviewed 198 patients with FIGO stage IB2-IVA cervical cancer, positive PLNs, and negative para-aortic lymph nodes (PALNs) from 2004 to 2015 at two tertiary centers. All patients underwent pelvic radiotherapy (PRT) or SRVRT with IMRT. The SRVRT extended the PRT field cranially to the level of the left renal vein. The prescribed doses were 45-50.4Gy in 1.8Gy per fraction.
Results: Overall, 118 and 80 patients underwent PRT and SRVRT, respectively. The SRVRT group had more advanced disease based on FIGO stage, common iliac PLNs, and number of PLNs. The median follow-up was 63months (range: 7-151months). PALN failure was experienced by 28 patients (23.7%) in the PRT group and 1 patient (1.3%) in the SRVRT group (p<0.001). Compared with PRT, SRVRT significantly improved 5-year PALN recurrence-free survival (56.8% vs. 100%, p<0.001) and cancer-specific survival (56.5% vs. 93.9%, p<0.001) among patients with common iliac PLNs or ≥3 PLNs. No significant differences were observed in these outcomes among patients with PLNs below the common iliac bifurcation and 1-2 PLNs. The SRVRT did not increase severe toxicities.
Conclusions: Risk-based radiation field based on PLN location and number could optimize outcomes for PLN-positive cervical cancer.
Keywords: Cervical cancer; Clinical outcome research; Intensity-modulated radiation therapy; Para-aortic irradiation.
Copyright © 2017 Elsevier Inc. All rights reserved.