Biopsia rápida por congelación en el diagnóstico de tumores de ovario: correlación diagnóstica según diámetro y peso en tumores de origen epitelial / Frozen sections in the diagnosis of ovarian tumors: accuracy by diameter and weight in epithelial ovarian tumors

ABSTRACT

Background: Adequate management and treatment of ovarian carcinoma requires a complete surgical staging supported by frozen-section examination. To achieve this goal it is necessary a high level of accuracy. Aim: To evaluate the accuracy of frozen-sections in ovarian carcinoma considering the influence of tumor diameter and weight. Patients and methods: Retrospective study of frozen-sections performed in patients with ovarian tumors who underwent surgery. Frozen- and permanent- sections were divided into three categories (benign, borderline and malignant) and stratified by diameter (<10 cm, 10 to 20 cm, >20 cm) and weight (<700 g, 700 a 1400 g, >1400 g). The diagnostic correlation, sensitivity, specificity, predictive values and accuracy of each frozen-section diagnosis were determined. Results: Eight hundred forty two ovarian tumors that underwent frozen-sections between january 1988 and october 1998 were studied. Final diagnosis was 86,7 percent benign, 2,7 percent low malignant potential (LMP) and 10,6 percent malignant. The diagnosis correlation between frozen- and permanent-sections was 98,2 percent. Misdiagnosis was in epithelial ovarian tumors, particularly in LMP tumors. Sensitivity, specificity, positive- and negative- predictive values and accuracy of the four hundred eighty nine epithelial tumor were 92,6 percent, 99,2 percent, 96,7 percent, 98,2 percent and 97,9 percent, respectively. Diagnostic correlation was higher in epithelial ovarian tumors with diameter <10 cm (98,2 percent v/s 93,8 percent) and weight <700 g (96,9 percent v/s 88,9 percent). Conclusions: Diagnostic correlation with permanent-section examination, sensitivity, specificity and predictive values of frozen-sections are high in ovarian tumors. Accurate diagnosis at frozen sections of epithelial ovarian tumors with diameter >10 cm or weight >700 g (particularly in LMP tumors) is difficult because of the extensive sampling required. Frozen-sections diagnoses are important to determine the type and extent of surgery performed at the initial operation