Influence of histologic type and age on survival rates for invasive cervical carcinoma in Taiwan

Objective. The aim of this study was to assess survival rates and to evaluate histologic type and age as prognostic factors for cervical carcinoma in an ethnically homogenous population in Taiwan. Methods. A retrospective analysis was conducted of 3678 cases of squamous cell carcinoma and adenocarcinoma that were diagnosed and treated for invasive cervical carcinoma between 1977 and 1994. Observed survival rates were estimated using the Kaplan-Meier method, and prognostic factors were assessed using Cox's proportional hazards regression analysis. Results. Correlating both FIGO stage and age with histologic type revealed a higher proportion of cases with adenocarcinoma in the lower FIGO stages (P = 0.0417). Further, we found that the younger the age group the higher the proportion of cases of cervical adenocarcinoma (P = 0.0006). The 5-year survival rate was lower for patients with adenocarcinoma than for patients with squamous cell carcinoma (66.5 vs 74.0%, P = 0.0009). The 5-year survival rates for FIGO stages I, II, III, and IV squamous cell carcinoma were 81.3, 75.2, 42.7, and 26.1%, respectively, while for adenocarcinoma they were 75.9, 62.9, 29.2, and 0%, respectively. The difference in survival rates between squamous cell carcinoma and adenocarcinoma was found mainly in stage I (P = 0.0039) and stage II (P = 0.0103), where radiotherapy was used as the primary treatment. Age also affected the overall Kaplan-Meier estimate of survival. The younger the age group, the better the survival rate (P < 0.0001). Multivariate analysis confirmed a highly significant association between survival rate and both histologic type (P < 0.0001) and age (P = 0.0037). Conclusions. Early stage cervical cancer (stages I and II) with a glandular component had a lower 5- year survival rate than squamous cell carcinoma in cases where radiotherapy was the primary treatment. We speculate that this difference in survival rates between cervical adenocarcinoma and squamous cell carcinoma was due to the relative ineffectiveness of radiotherapy as a primary treatment in cases of adenocarcinoma.