Frozen section evaluation of cervical cold knife cone specimens is accurate in the diagnosis of microinvasive squamous cell carcinoma

Objectives. The purpose of this study was to determine the accuracy of frozen section evaluation of cervical cold knife cone (CKC) specimens in the diagnosis of microinvasive squamous cell carcinoma (SCC). Methods. Using ICD-9 codes for invasive and microinvasive carcinoma of the cervix, a medical record from 1986 to 1998 identified 110 potential study subjects. Society of Gynecologic Oncologists criteria including depth of invasion ≤3 mm and absence of lymph-vascular space involvement were utilized for the diagnosis of microinvasion. Twenty-seven patients met study criteria including a frozen section diagnosis of microinvasive SCC on a cervical CKC specimen at our institution. A pathologist, blinded to patient diagnosis, reevaluated the histologic findings, including grade, depth of invasion, and cell type. Results. Median age of diagnosis was 41 years. Median follow up was 3.6 years. The median time for pathologic review was 28 min (range 15-44 min). Independent retrospective pathologic review of the permanent sections confirmed the diagnosis of microinvasion in 100% (27/27) of patients. No patient experienced a cervical SCC recurrence. At 10 years, disease-specific survival is 100%. Conclusions. Frozen section is reliable in the evaluation of CKC specimens with microinvasive SCC: this may afford a simplified surgical approach in certain cases. This accuracy should not be assumed to apply to adeno- or adenosquamous carcinoma of the cervix. At our institution which relies heavily on intraoperative pathologic evaluation, utilizing frozen section diagnosis as the basis for definitive surgical approach did not negatively impact disease-free survival.