Fine-needle aspiration cytodiagnosis of endometriosis in cesarean section scar and rectus sheath mass lesions -- a study of seven cases.

The diagnosis of endometriosis is usually established by a biopsy. Since endometriotic lesions can present as a mass lesion, it seems feasible to investigate them by the noninvasive method of fine-needle aspiration cytology (FNAC). In this study, seven cases (5 from a cesarean scar and 2 from rectus sheath) are presented in which FNAC was indicative of endometriosis. The aspirate was obtained using a disposable 10 ml syringe and 22 gauge needle. The material was collected as syringe and needle washings in a cytology container in which 30% ethyl alcohol was present. From half of this material, filter preparations were made on size 3 mum filters and stained by Papanicolaou method, while the remaining aspirate was spun and a cell block was made from the sediment and sections cut and stained with hematoxylin-eosin stain. In all cases the cytologic preparations showed tubular structures indicative of endometrial tissue and stromal cells indicative of endometriosis. This was further confirmed on examination of cell blocks, which showed histologic features of endometriosis characterized by endometrial glands separated by endometrial stroma and rare siderophages. The seven cases described are interesting, since the cytohistological finding in FNAC sample and cell block not only were indicative of the diagnosis of endometriosis, but also obviated the need for an invasive surgical procedure. (c) 2008 Wiley-Liss, Inc.