CUTANEOUS ENDOMETRIOSIS AS A DIAGNOSTIC PITFALL OF FINE-NEEDLE ASPIRATION BIOPSY - A REPORT OF 3 CASES

We describe the cytologic features of three cases of cutaneous endomet riosis in young women (average age, 27 years); two cases presented as lower abdominal nodules associated with a previous cesarean section sc ar. The third case presented as a 5 x 4-cm inguinal mass. The smears w ere generally cellular, consisting of epithelial and stromal fragments . Epithelial cells showed large, hyperchromatic nuclei and moderate am ounts of cytoplasm, with considerable nuclear overlapping. The stromal aggregates also showed crowded, overlapping nuclei and scant, admired , hemosiderin-laden macrophages. These features, combined with isolate d cells in the background, made differentiation from metastatic carcin oma extremely difficult. Cutaneous endometriosis can present a diagnos tic pitfall on fine needle aspiration, especially in the absence of a previous history of abdominal surgery or established diagnosis of endo metriosis.