Does the addition of radiation to adjuvant chemotherapy improve the survival for early‐stage (tumor size ≤4 cm) small cell neuroendocrine carcinoma of the cervix after surgery? A population‐based study

BACKGROUND: To assess the potential benefit of adding radiotherapy to adjuvant chemotherapy in patients with early-stage small cell neuroendocrine carcinoma of the cervix (SCNEC) (tumor size ≤4 cm) after surgery. METHODS: The Surveillance, Epidemiology, and End Results (SEER) database was queried for patients with early-stage SCNEC who received primary surgery and at least adjuvant chemotherapy from 1988 to 2018. Eligible patients were categorized into radiation and nonradiation group, survival outcomes were compared before and after propensity scoring matching (PSM). Cox regression analysis was used to identify risk factors in the nonradiation group. Accordingly, a scoring system was constructed to select patients who might benefit from the addition of radiation. RESULTS: No statistically significant difference in overall survival was observed between the two groups whether before or after PSM (P > 0.05). However, the nonradiation group exhibited better survival outcomes than the radiation group for patients aged ≤50 years (P = 0.035) and patients receiving modified/radical hysterectomy (P = 0.031). Conversely, patients with stage T2a1 disease obtained greater benefit from radiation compared with nonradiation (P = 0.016). A scoring system incorporating T stage, tumor size, and number of lymph nodes examined during surgery was developed to stratify patients into low-risk (total points ≤27.9) and high-risk (total points >27.9) groups. Notably, patients in the high-risk group had improved outcomes with the addition of radiotherapy (P = 0.0052). CONCLUSION: The addition of radiation to adjuvant chemotherapy did not confer a survival benefit for every patient with early-stage SCNEC, except for those with stage T2a1 disease. Moreover, a scoring system was developed to preliminarily identify patients who might benefit from the addition of radiation.