Trisomy 21 as the only recurrent chromosomal anomaly in a clinically aggressive ovarian carcinoma

A case of a highly aggressive grade III poorly differentiated serous adenocarcinoma of the ovary was determined to exhibit trisomy 21 as the sole chromosomal abnormality. To eliminate the possibility that this trisomy was constitutional, the patient's blood cells were subjected to locus specific 21q22.13 approximately q22.2 chromosome probe using fluorescence in situ hybridization (FISH). Concurrently, using FISH and the same probe the tumor tissue was also tested. We discovered that 48% of the cells of the tumor tissue either had trisomy or tetrasomy of chromosome 21. Two normal signal patterns for chromosome 21 in blood and absence of Down morphology in the patient confirmed the presence of trisomy to be limited to the tumor tissue. To the best of our knowledge, this is the only case where trisomy 21 was shown to be the sole chromosomal anomaly in a serous carcinoma of the ovary. Tumorigenesis in gynecologic malignancies is discussed in the light of oncogenes present on chromosome 21.