Improved outcomes of palliative radiotherapy combined with immune checkpoint inhibitors in recurrent or metastatic cervical cancers.

Background: Immunotherapy provides a remarkable survival advantage for patients with recurrent or metastatic cervical cancer (R/M CC). However, the role of immunotherapy in combination with radiotherapy in R/M CC remains unclear.

Methods: We retrospectively analyzed factors affecting immunotherapy effectiveness in patients with R/M CC. Clinical outcomes including tumor response and patient survival were assessed. Kaplan-Meier curves with the log-rank test were employed to compare survival data. Cox regression analysis was utilized to investigate prognostic factors.

Results: A total of 65 R/M CC patients treated with immune checkpoint inhibitors were eligible for analysis. We found that immunotherapy combined with palliative radiotherapy showed a significant positive correlation with complete response (OR = 6.31; 95 %CI: 1.74-22.91; p = 0.005). The 36-month progression-free survival (PFS) rate (73.7 % vs 33.8 %, p = 0.0048) and 36-month overall survival (OS) rate (85.7 % vs 38.7 %, p = 0.0043) were also prominently increased. We further demonstrated that patients prolonged 36-month PFS rate (69.9 % vs 15.2 %; p < 0.001) and 36-month OS rate (64.6 % vs 39.7 %; p = 0.032) when they had more than 4 cycles of immunotherapy. Meanwhile, our findings showed that patients with only recurrence had longer 36-month OS rate (77.7 % vs 44.4 % vs 40.1 %; p = 0.024) compared to those with only metastasis and both. We also observed that patients with squamous carcinoma had higher 2-year PFS rate (57.9 % vs 14.6 %; p = 0.042) than those with other pathological subtypes (adenocarcinoma, adenosquamous carcinoma and neuroendocrine carcinoma).

Conclusions: The combination of immunotherapy and palliative radiotherapy increased complete response rates and improved survivals in recurrent or metastatic cervical cancer patients.