Re-irradiation for recurrent cervical cancer: A single institutional experience.

Purpose: Salvage treatment of recurrent cervical cancer of patients with a history of radiotherapy is currently a major clinical challenge. The purpose of our study was to retrospectively analyze clinical outcomes of radiation in patients with recurrent cancer who have previously received radiotherapy at our hospital and further explore the efficacy and safety of this treatment modality. Methods: All consecutive patients who underwent re-irradiation were included in our department between January 2015 and December 2017. All the patients received Volumetric Modulated Arc Therapy (VMAT) alone or VMAT followed by three dimensional-image-guided brachytherapy (3D-IGBT). The volume and dose for re-irradiation depended on previous radiation fields, dosimetry and recurrence sites. All patients received systemic chemotherapy before or after re-irradiation. Results: Fifty patients were included in our study. The median time from primary radiotherapy to re-irradiation was 12 months. Local recurrence, which was the most common failure following primary treatment, was present in 25 patients (50.0 %) while regional recurrence, loco-regional recurrence and distant recurrence combined in-filed recurrence was present in 8 (16.0 %), 9 (18.0 %) and 8 patients (16.0 %). Re-irradiation dose to lymph nodes was 45 Gy with or without a boost up to 55-60 Gy, and to the gross mass was 36-45 Gy with or without a boost up to 45-61 Gy. The median follow-up period was 22 (range,4-59) months. The 3-year local control (LC), progression-free survival (PFS), and overall survival (OS) rates were 58.0, 38.7, and 44.4 %, respectively. The median time of PFS and OS was 14 and 26 months, respectively. The interval between two successive radiotherapies beyond 12 months was significantly associated with better LC and PFS (p ≤ 0.05), but without the benefit of OS (p > 0.05). Serum SCC antigen level less than 1.5 ng/ml had a significantly better impact on PFS (p ≤ 0.05). Overall, 14 patients (28 %) experienced ≥ grade 3 acute toxicities, while 9 (18 %) experienced ≥ grade 3 late toxicities. Conclusions: Re-irradiation with VMAT is an effective and safe salvage treatment option with a reasonably good clinical outcome and toxicity profile in selected patients. In our experience, recurrent cancer patients with an interval between two successive radiotherapy courses beyond 12 months and with a serum SCC-Ag level less than 1.5 ng/ml, had improved outcomes.