[Value of endocervical margin examination of conization specimens. Prospective study conducted on 150 patients]

To assess the usefulness of frozen sections (FS) on endocervical margin in surgical conization or loop electrosurgical specimens.

In a prospective study, 150 patients were treated from October 1995 to December 1997: 69 cases without FS, 81 cases with FS. CIN on frozen section resulted in an immediate additional resection.

In the group without FS, 13 patients had involved endocervical margin by high-grade CIN (18.8%). Frozen section was impossible in a conization specimen that was too short. FS revealed 64 normal glandular epitheliums, seven squamous metaplasias in which two lesions were under-evaluated (being in fact CIN on permanent sections), eight high-grade CIN followed by additional resection in six cases and two invasive carcinomas. Endocervical margin on additionals section were always free of disease. The rate of failure was 2.6% among 77 cases. This rate corresponded to two under-evaluations. Invasive carcinoma and CIN without additional resection were excluded because frozen section only allowed a peroperative diagnosis. The average height of the cone and the rate of complications were similar. Repeat surgery was necessary in nine cases in the group without frozen section, in which five showed residual lesions, absent in the other group.

The ultimate histological interpretation was never difficult after frozen section. This method permits reduction of cases with involved cone margin and residual lesions and, despite some limitations, it may be useful for surgical management.