INTERPHASE FLUORESCENCE IN-SITU HYBRIDIZATION FOR TRISOMY-12 ON ARCHIVAL OVARIAN SEX CORD-STROMAL TUMORS

Trisomy 12 is a nonrandom chromosomal abnormality found in a large pro portion of ovarian sex cord-stromal tumors (OSCTs), including thecoma- fibromas (TFs) and granulosa cell tumors (GCTs). The prognostic signif icance of trisomy 12 in these tumors, however, is unknown. A series of 16 OSCTs, obtained from patients with long-term follow-up, was analyz ed for the presence of trisomy 12 by interphase fluorescence in situ h ybridization on paraffin-embedded sections. Sections of the contralate ral nonneoplastic ovary were available in five cases and utilized as c ontrols. Evidence of trisomy 12 was detected in 9 of 10 TFs, and contr ary to previous reports, in only one of six GCTs. One TF with trisomy 12 was a malignant variant that resulted in: the death of the patient in 5 months, but the remaining TFs with trisomy 12 were cytologically and clinically benign in those:with follow-up available. The single GC T with trisomy 12 was 9 nonaggressive, stage 1 lesion without evidence of recurrence after 264 months, whereas those GCTs without trisomy 12 , included one stage 2 tumor and a cytologically atypical GCT with tum or necrosis and an elevated number of mitotic figures. The evidence su ggests that the great majority of OSCTs with trisomy 12 is clinically benign, but not all benign OSCTs have trisomy 12. We conclude that the presence of trisomy 12 is of limited prognostic usefulness in OSCTs. (C) 1994 Academic Press, Inc.