Cervical neuroendocrine carcinoma with non-neuroendocrine components has a poorer prognosis than pure neuroendocrine carcinoma

OBJECTIVE: To investigate whether neuroendocrine carcinoma of the cervix (NECC) with coexisting non-neuroendocrine tumor components (mixed subtype) is associated with a worse prognosis compared to the pure subtype. METHODS: A total of 121 patients diagnosed with NECC at 4 participating hospitals in the Republic of Korea between August 1997 and November 2023 were included. All diagnoses were confirmed through surgical specimens obtained via conization or hysterectomy. Clinical and pathological variables were collected through medical record review. The association between tumor heterogeneity (pure vs. mixed subtype) and progression-free survival (PFS) was analyzed using a Cox proportional hazards model. RESULTS: The majority of patients was diagnosed at stage I (62%), had small cell histology (63%), and presented with the pure subtype (66%). Most patients (n=106) underwent surgery with or without adjuvant therapy as initial treatment. In univariate analysis, there was no significant difference in PFS between the pure and mixed subtypes (p=0.952). However, after adjusting for covariates, the mixed subtype was significantly associated with worse PFS compared to the pure subtype (adjusted hazard ratio=3.16; 95% confidence interval=1.58-6.35; p=0.001). CONCLUSION: NECC with non-neuroendocrine components is associated with significantly worse prognosis than the pure subtype.