Evaluation of a new instrument designed for directed cervical excision: cone biopsy excisor

Our objective was to compare a newly designed instrument, the Cone Biopsy Excisor (CBE; Apple Medical Corporation, Bolton, MA), with the standard loop electrosurgical excision procedure (LEEP) for providing a cervical conization specimen with the best achievable margin quality for histological evaluation.

Patients referred to the dysplasia clinics at Hartford Hospital, St. Francis/Mt. Sinai Hospital and the University of Connecticut Health Center/New Britain General Hospital were randomized to either the CBE procedure or LEEP. To be included in the study, patients had to meet at least one of the following criteria: biopsy-proven cervical intraepithelial neoplasia grade 2 or 3, unsatisfactory colposcopy, positive endocervical curettage, or one or more degrees of cytohistological discrepancy. Exclusion criteria included pregnancy, undiagnosed uterine bleeding, acute cervicitis, or biopsy-proven invasive carcinoma. Forty-seven patients were randomized to the CBE and 48 to LEEP. To obtain the cervical specimen, third- and fourth-year obstetricalgynecological residents used Force II Valley Lab Generators (Valley Lab, Boulder, CO) at a blend one setting (80/20 blend of cutting and coagulation). Wattage ranged from 25 to 45, according to the size of the instrument used. Pathological reports were reviewed by the author to determine the amount of fragmentation and for tissue diagnosis. Slides of the specimens were evaluated by two blinded gynecological pathologists. The slides were analyzed for margin quality and thermal damage. A thermal damage score was assigned, evaluating the number of cells affected and the depth of damage. This scoring system, designed by the pathologists, ranged from 3 (least thermal damage) to 9 (greatest thermal damage).

Of 47 CBE cases and 48 LEEP cases, 41 (87%) and 8 (17%), were single specimens X (1) = 44.6; (p < .0001). The mean number of specimens submitted to pathology per case was 1.2 (+/- 0.6) in the CBE group and 2.3 (+/- 0.9) in the LEEP group (t - 6.89;p < .001). Margins obliterated by thermal artifact included 3 of 47 (6%) in the CBE group and 16 of 48 (33%) in the LEEP group (X (1) = 9.16;p < .003). Mean thermal damage score was 4.1 (± 0.9) in the CBE group and 6.1 (± 1.8) in the LEEP group (t = 6.77; p < .001).

The Cone Biopsy Excisor provides a cervical specimen that exhibits less fragmentation and less thermal damage and has margins that are less likely to be indeterminate than that provided by standard LEEP.