Clinical value of DNA image cytometry in effusions with atypia

Malignant cells in serosal effusions provide essential information about the extent of malignant disease. The main aim of this study was to examine the additional diagnostic value of DNA image cytometry for cases with uncertainty in the cytological diagnosis. In addition, the feasibility of automated nuclei detection was investigated. Out of 457 cases, 33 samples in 32 patients were diagnosed with "atypia" (probably benign) and 21 as "suspicious for malignancy." DNA image cytometry was performed on these 54 cases and on an additional group of 14 cytologically malignant cases. The results show that automatic classification is useful for separation of control cells, i.e., lymphocytes and neutrophilic granulocytes from other mononuclear cells. In 21 cases an insufficient number of control cells were measured. Seventy-two percent of the cytologic malignant cases were aneuploid. In contrast, in none of the cases with "atypia" and in only 2 of the cases "suspicious for malignancy" was aneuploidy present (2 of the remaining 32, 6%). From the cases with follow-up, a malignancy in the pleural fluid was present in 2 out of 17 cases with "atypia" and in 5 out of 10 with a "suspicious for malignancy" cytologic diagnosis, respectively. In conclusion, the additional diagnostic value of DNA image cytometry in cases with a cytological diagnosis of "atypia" or "suspicious for malignancy" is limited. Diagn. Cytopathol. 1999;21:112-116.