title: Cystic adult ovarian granulosa cell tumor as a potential source of false negative diagnosis in ovarian cytology. A case report.
abstract: BACKGROUND
  Adult granulosa cell tumors (AGCT), unilocular or multilocular, with thin-walled cysts, are extremely rare. They can be erroneously diagnosed as follicular cysts by sonography and fine needle aspiration and therefore may be a source of false negative results.
  
  
  METHODS
  Laparoscopy was performed on a 29-year-old woman in whom a cystic ovarian mass, probably benign, was diagnosed by transvaginal sonography. The smears obtained from the cyst revealed a moderate amount of regular, small cells with scant cytoplasm and round to oval nuclei with finely granular chromatin without longitudinal grooves. These granulosa cells were arranged singly and in small groups. Very scarce cellular aggregates, microfollicular or rosettelike, some containing amorphous material and resembling Call-Exner bodies, were identified. Histologic study of the cystic wall confirmed the diagnosis of multilocular cystic AGCT with a microfollicular pattern.
  
  
  CONCLUSIONS
  The finding of a moderate to abundant amount of regular granulosa cells, with or without nuclear longitudinal grooves, during cytologic examination of ovarian cysts considered benign by ultrasonography requires a careful search for microfollicular differentiation and Call-Exner bodies due to the rare but possible occurrence of cystic AGCT.
mesh_terms: D000328:Adult; D003581:Cytodiagnosis; D003937:Diagnosis, Differential; D005188:False Negative Reactions; D005260:Female; D005500:Follow-Up Studies; D006106:Granulosa Cell Tumor / Q000000981:diagnostic imaging / Q000473:pathology*; D006801:Humans; D010535:Laparoscopy; D010048:Ovarian Cysts / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery; D010051:Ovarian Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology*; D014463:Ultrasonography