Comparison of clinical behaviors and responses to radiation between squamous cell carcinomas and adenocarcinomas/adenosquamous carcinomas of the cervix.

BACKGROUND

Adenocarcinomas/adenosquamous carcinomas (AC/ASC) are relatively uncommon histological subtypes in cervical cancer. In this study, we retrospectively compared the clinical behaviors and responses to radiation of squamous cell carcinomas (SCC) and AC/ASC in patients with stage I-IVA cervical cancer primarily treated by radiotherapy (RT).

METHODS

Nine hundred twenty-eight patients with cervical cancer primarily treated with RT were included in this study. Ninety-four percent of the patients had SCC and 6% had AC/ASC. The association of histological subtype to various clinical parameters was assessed. Tumor response and failure patterns were analyzed, and the prognostic significance of histological subtype and other clinical parameters were evaluated by univariate and multivariate analyses.

RESULTS

(1) Patients with AC/ASC had a significantly higher percentage of bulky I-IIA disease, a younger age (< 45 years), and an elevated carcinoembryonic antigen (CEA) level, but a lower percentage of elevated squamous cell carcinoma antigen (SCC-Ag) level, than patients with SCC. Hemoglobin (Hb) levels and lymph node status were not significantly different between SCC and AC/ASC patients. (2) A higher percentage of AS/ASC patients had residual induration 2 to 3 months after RT than those with SCC (40% vs. 21.6%, p = 0.008). Higher local failure rates were found for AC/ASC patients compared to SCC patients (38% vs. 15%, p = 0.001). (3) The 5-year disease-specific survival rate was 66% and 50% for SCC and AC/ASC patients, respectively (p = 0.016). Advanced stages, Hb levels lower than 10 g/dl, positive lymph nodes, AC/ASC histological subtype, and SCC-Ag levels higher than 10 ng/ml were independent prognostic factors for worse survival for all patients. For patients with AC/ASC in particular, only stage and positive lymph nodes were significant prognostic factors.

CONCLUSION

Cervical cancer patients with AC/ASC are relatively younger and have a higher incidence of elevated CEA and a lower incidence of elevated SCC-Ag levels than those with SCC. For AC/ASC patients, the tumor responses to RT were relatively slow and poor. This group of patients had a worse survival rate than patients with SCC, mainly because of the higher incidence of uncontrolled local disease for AC/ASC patients.