Is there really a difference in survival of women with squamous cell carcinoma, adenocarcinoma, and adenosquamous cell carcinoma of the cervix?

Background: The authors' aim was to assess whether there is a difference in biologic behavior and survival in comparing adenocarcinoma (AdCA), squamous cell carcinoma (SCC), and adenosquamous carcinoma (Ad/SC) of the cervix.
Methods: Cancer registrars at 703 hospitals submitted anonymous data on 11,157 patients with cervical cancer diagnosed and/or treated in 1984 and 1990 for a Patient Care Evaluation Study of the American College of Surgeons. Among these patients, 9351 (83.8%) had SCC; 1405 (12.6%), AdCA; and 401 (3.6%), Ad/SC cancers. There were no significant changes in percentages of the different histologic types between the study years 1984 and 1990, nor was the patient distribution different regarding age, race/ethnicity, and socioeconomic background for each histologic group. Furthermore, the distribution of patients who had had a hysterectomy did not change between 1984 and 1990.
Results: A larger percent of patients with SCC (63.8%) than those with Ad/SC (59.8%) or AdCA (50.2%) had tumors larger than 3 cm at greatest dimension. Early stage patients (IA, IB, IIA) often were treated by hysterectomy alone (45.5%) or combined with radiation (21.1%). The remaining patients (21.9%) received radiation alone. Of the patients with clinical stage I disease, 7.6% of Ad/CA patients, 15.5% of Ad/SC patients and 12.6% of SCC patients had positive nodes. Although patients with SCC had higher survival rates for all four clinical stages (I-IV), the differences were only significant for Stage II patients. Patients with clinical stage IB SCC and AdCA treated by surgery alone were found to have significantly better survival rates (93.1% and 94.6% at 5 years, respectively) than women treated by either radiation alone or a combination of surgery and radiation (P < 0.001, both histologic comparisons). For women with Ad/SC tumors, however, the 5-year survival rate was 87.3% for those receiving combined treatment compared with those receiving surgery alone (69.2%) or radiation alone (79.2%). However, these survival curves were not significantly different (P = 0.496). One hundred six patients with positive nodes were available for analysis. The 5-year survival rate of patients with SCC and positive nodes was 76.1%. Surprisingly, patients with Ad/SC and positive nodes had the highest 5-year survival rate (85.7%), whereas, women with AdCA and positive nodes had a sharply reduced 5-year survival rate (33.3%). The curves were significantly different (P < 0.01). For patients with clinical stage I, the risk factors for age, tumor size, nodal status, histologic features, and treatment were analyzed with Cox's multivariate regression. In this analysis, subset IB, greater tumor size, age 80 or older, and positive nodal status were each independently significant for poorer survival. Patients who were treated by surgery alone had a significantly better survival than patients who had other types of treatment or no treatment. Histologic characteristics had no significant effect on survival. In the analysis of patients with pathologic stage I disease, those with SCC had significantly poorer survival and those with Ad/SC had significantly better survival than patients with Ad/CA. Positive nodes had no significant independent effect on survival. In another analysis, tissue type was not found to be an important factor in recurrence time.
Conclusions: 1. Ad/CA and Ad/SC tumors were found to represent 12.6% and 3.6%, respectively, of a large series (N = 11,157) of cervical cancers diagnosed in 1984 and 1990 and reported to the Commission on Cancer of the American College of Surgeons. 2. Two thirds of women with early clinical stage disease (IA, IB, IIA) had hysterectomy as all or part of their primary therapy. 3. No significant differences were found in 5-year survival among the three tissue types in any clinical stage except American Joint Committee on Cancer stage II.