How important is removal of the parametrium at surgery for carcinoma of the cervix?

OBJECTIVES: The aims of this study were (1) to determine the incidence and factors predictive for pathologic parametrial involvement in clinical stage IA1/2 and IB1 cervical cancer after radical surgery and (2) to identify a population at low risk for pathologic parametrial involvement. METHODS: All patient information was collected prospectively and extracted from a cervical cancer radical surgery database. Selection criteria for surgery were generally based upon tumor size, with the cutoff for surgery between 3 and 4 cm. Parametrial involvement (PI) was defined as either positive parametrial lymph nodes (PMLN) or malignant cells in the parametrial tissue (PT) (including lymphovascular channels) by either contiguous or discontiguous spread. Statistical analysis included the chi2 test, the Wilcoxon rank test, and the Mantel-Haentzel test. RESULTS: Between July 1984 and January 2000, 842 patients underwent radical surgery for clinical stage IA1/2 and IB1 cervical cancer at our center. Forty-nine patients (6%) had positive pelvic lymph nodes. Thirty-three patients (4%) had pathologic PI, 8 in the PMLN and 25 in the PT (none had both). PI was associated with older age (42 vs 40 years, P < 0.04), larger tumor size (2.2 vs 1.8 cm, P < 0.04), higher incidence of capillary-lymphatic space invasion (85% vs 45%, P = 0.0004), tumor grades 2 and 3 (95% vs 65%, P = 0.001), greater depth of invasion (18.0 vs 5.0 mm, P < 0.001), and pelvic lymph node metastases (44% vs 5%, P < 0.0001). The incidence of PI in patients with tumor size < or =2 cm, negative pelvic lymph nodes, and depth of invasion < or =10 mm was 0.6%. CONCLUSION: Pathologic parametrial involvement in clinical stage IA1/2 and /IB1 cervical cancer is uncommon. Acknowledging that almost all patients with pelvic lymph node metastases and a high proportion of patients with tumor invasion >10 mm will receive adjuvant radiation regardless of the radicality of surgery, a population at low risk for pathologic parametrial involvement can be identified. These patients are worthy of consideration for studies of less radical surgery performed in conjunction with pelvic lymphadenectomy.