Use of cytogenetic analysis of body fluids in cancer diagnosis.

Direct chromosome preparations were made from 52 malignant and 21 non-malignant effusions. An effusion was classified as malignant if 2% of the counted cells showed abnormal karyotypes. There was a significant relationship between diversified karyotypes and the pathological nature of tumours: diversity of karyotypes was much higher in undifferentiated adenocarcinoma, anaplastic carcinoma and embryonal cell carcinoma cells than in well-differentiated cancer cells. Diagnosis was positive for 38 of the 52 malignant effusions by cytological examination (73% sensitivity), and positive for 41 of the 52 by cytogenetic analysis (78% sensitivity). There were no false positive results using both cytogenetic and cytologic examinations (92% sensitivity). Particularly in patients with equivocal cytology, cytogenetic analysis appears to be a useful tool in the diagnosis of malignant effusions.