Re-irradiation in oligorecurrence and oligometastatic cervical cancer in modern radiotherapy era

Recurrent cervical cancer remains a therapeutic challenge despite advances in primary treatment. The emerging paradigm of oligorecurrence and oligometastasis has opened avenues for curative-intent local therapies, including re-irradiation. Modern radiotherapy techniques have enabled high-dose delivery with acceptable toxicity. This study aims to assess clinical outcomes and treatment-related toxicities in patients with oligorecurrent or oligometastatic cervical cancer treated with modern re-irradiation techniques.

This retrospective study included 20 cervical cancer patients with oligorecurrence or synchronous/metachronous oligometastases (≤ 5 lesions) who underwent at least one course of re-irradiation. Survival outcomes including locoregional recurrence-free survival (LRRFS), distant metastasis-free survival (DMFS), progression-free survival (PFS), and overall survival (OS) were estimated using Kaplan-Meier analysis. Genitourinary (GU), gastrointestinal (GI), and hematologic toxicities were assessed and graded based on CTCAE version 5.0.

The median age was 53 years (range: 33-70), with 75% initially diagnosed at FIGO 2018 stage III. The predominant histologies were squamous cell carcinoma (50%) and adenocarcinoma (45%). Recurrences most commonly involved pelvic (30%) and para-aortic (30%) lymph nodes, with 50% occurring in-field. Stereotactic body radiotherapy (SBRT), volumetric modulated arc therapy (VMAT), and MR-guided adaptive brachytherapy (MR-GABT) were the most commonly used re-irradiation modalities, employed in 95% of patients. Median times to first and second recurrence were 11.1 months (IQR: 6.0-17.3) and 13.7 months (IQR: 5.6-21.7), respectively. At a median follow-up of 33.6 months, PFS, LRRFS, DMFS, and OS rates after the first recurrence were were 31.8%, 33.6%, 60.5%, and 84.2% respectively. Grade ≥ 2 genitourinary (GU), gastrointestinal (GI), and hematologic toxicities were observed in 40%, 25%, and 55% of patients, respectively. Grade 3 hematologic toxiciy was 25% and mostly occurred during chemotherapy administration. No grade ≥ 3 GU or GI toxicities were reported. The mean accumulated D0.03 cc after re-irradiation to bladder, rectum, sigmoid and bowel for in-fied/out-of-field were 83.8 ± 6.7/78.5 ± 7.5), 71.2 ± 3.9/69.5 ± 5.2, 68.0 ± 5.5/61.0 ± 5.3, and 62.9 ± 4.6/62.4 ± 7.1 GyEQD2₍₃₎, respectively.

Re-irradiation with contemporary radiotherapy techniques appears to be a feasible and effective salvage option for selected patients with limited recurrent or metastatic cervical cancer, yielding favorable survival and acceptable toxicity profiles.