Impact of histological subtype on survival of patients with surgically-treated stage IA2-IIB cervical cancer: adenocarcinoma versus squamous cell carcinoma.

OBJECTIVES: To evaluate the significance of adenocarcinoma (AC) compared with squamous cell carcinoma (SCC) with regard to the survival of surgically-treated early stage cervical cancer patients.

METHODS: We retrospectively reviewed the medical records of 520 patients with FIGO stage IA2-IIB cervical cancer who were treated with radical hysterectomy with or without adjuvant radiotherapy between January 1998 and December 2008. The patients were classified according to (i) pathological risk factors (low-, intermediate-, or high-risk group) and (ii) adjuvant radiotherapy (concurrent chemoradiotherapy [CCRT group] or radiotherapy alone [RT group]). Survival outcomes were examined by Kaplan-Meier method and compared with Log-rank test. Multivariate analysis for disease-specific survival (DSS) was performed using Cox proportional hazards regression model to investigate the prognostic significance of histological subtype.

RESULTS: AC histology was associated with significantly decreased DSS compared with SCC histology in the intermediate- and high-risk groups (hazard ratio: 3.06 and 2.88, respectively, both P<0.05) while there was no survival difference in the low-risk group (P=0.1). Among patients who received any types of adjuvant radiotherapy, DSS of AC histology patients were significantly poorer than SCC histology. Multivariate analysis demonstrated AC histology to be an independent predictor of decreased DSS in both CCRT and RT groups. Moreover, pelvic nodal metastasis significantly predicted the poor survival of patients with AC histology who received CCRT in multivariate analysis

CONCLUSIONS: Adenocarcinoma is an independent prognostic indicator of poor survival in early stage cervical cancer patients with intermediate- and high-risk factors, regardless of the type of adjuvant radiotherapy after radical hysterectomy.