Large loop excision of the transformation zone (LLETZ): a pathologic evaluation

Forty-six LLETZ cone biopsies were performed at the Medical College of Georgia from January 1991 through December 1991. All LLETZ cones were performed for diagnostic reasons following colposcopic biopsies. The majority of procedures were done by residents in obstetrics and gynecology with direct faculty supervision. All specimens were critically evaluated by one pathologist with regard to specimen orientation, thermal artifact, margins, histologic diagnosis, and overall specimen adequacy. The median number of specimens obtained per patient was two, with a maximum of eight. Sixteen patients had a separate endocervical specimen obtained. Thermal artifact was graded as slight in 16 cases, moderate in 18 cases, and severe in 12 cases. The transformation zone was identified in 33 cases. Margins were positive in 17 cases, negative in 21 cases, and nonevaluable in 8 cases. Only 13 LLETZ specimens were believed to compare in quality to a cold-knife cone biopsy. The main criticism about the specimens was the effect of thermal artifact on critical histologic evaluation. In three cases, the thermal artifact precluded an accurate enough evaluation to rule out microinvasion. Mucosa missing at the margins or inadequate representation of the transformation zone were major reasons to call a specimen inadequate. Endocervical specimens suffered the most thermal injury. Orientation of fragmented cone specimens present a problem in histologic evaluation. A major emphasis needs to be placed on the proper indications for LLETZ cone biopsy as well as education of practitioners and pathologists in proper specimen handling.