Radiotherapy for Postoperative Vaginal Recurrences of Cervical Cancer Patients: Analysis of Recurrent Causes and Prognosis

Abstract

Vagina is the most common site of cervical cancer recurrence, and salvage radiotherapy (RT) is recommended owing to its effectiveness and tolerable adverse events. Several studies have focused on prognostic factors of RT treatment for postoperative recurrent cervical cancer patients. However, few researches identified different recurrent causes as a prognostic factor and studied the relationship between recurrent causes and survival. The aim of this study was to identify the recurrent causes affecting prognosis of vaginal recurrent patients treated with salvage RT. One hundred and twenty-six female patients with vaginal recurrent cervical cancer, treated with salvage RT between July 2011 and January 2020, were reviewed in this study. Among these patients, a combination of EBRT and BRT was delivered to 94 patients, EBRT alone was delivered to 20 patients. Causes of recurrence were distributed into five groups: (1) selection of surgical indication (n = 15): included ①surgery beyond indication (n = 8) and ②neoadjuvant therapy (n = 7);(2) Positive surgical margin (n = 18); (3) nonstandard RT (n = 20): include ④no RT, despite indications of postoperative RT (n = 15), and ⑤insufficient postoperative RT dose (n = 5); (4) with risk factors but no indication for RT according to the Sedlis criteria (n = 29): include ⑥non-squamous carcinoma (n = 7) and ⑦only one intermediate risk factor in Sedlis criteria (n = 22); (5) HPV infection (n = 44). Log-rank tests and Cox proportional hazards regression methods were used to identify prognostic factors. The median follow-up time of the 126 cervical cancer patients was 39.1 months with estimated 5-year OS, PFS and LC rates of 79%, 75% and 86%, respectively. In multivariate analysis, recurrence pattern (including endovaginal recurrence, paravaginal recurrence, invasion of surrounding organs and distant metastasis, p < 0.05) and causes of recurrence were independent prognostic factors for OS. Recurrence because of "(1) the selection of surgical indication" (p < 0.05) was associated with poor OS, while recurrence because of "(2) positive surgical margin" was associated with prolonged OS. Multivariate analysis also revealed that recurrence pattern, causes of recurrence (p < 0.05) and re-irradiation were independently factors for PFS. Majority of patients with recurrence causes of HPV infection (79.5%) and positive surgical margin (77.8%) experienced endovaginal recurrence. Patients with recurrence cause of selection of surgical indication had the highest proportion (26.7%) of recurrence with invasion of surrounding organs, and 53.3% experienced re-irradiation. The results this research suggest that salvage RT is an effective treatment for vaginal recurrences in postoperative patients with cervical cancer. Causes of recurrence was an independently factor for OS and PFS, and recurrence caused by selection of surgical indication was associated poor survival.