Diagnostic and predictive validity of DNA image cytometry in soft tissue tumors

Malignant neoplasms are associated with chromosomal aberrations. This phenomenon called aneuploidy can be substantiated by interactive DNA cytometry and is accepted as a major prognostic parameter in tumor biology and oncology. In a retrospective study 114 non-infantile soft tissue tumors were analysed by DNA cytometry. The results were compared with classical morphological parameters. As a marker for malignancy in soft tissue lesions, DNA aneuploidy substantiated by cytometry has a sensitivity of 94% and a specifity of 82%: 50 of 53 malignant soft tissue tumors were DNA aneuploid; from 61 non-sarcomatous soft tissue tumors 11 were found to be aneuploid. These lesions were classified as intermediate dignity. No aneuploid tumor could be found among 30 histologically benign soft tissue tumors. The positive predictive value of DNA cytometry was 82%: of 61 aneuploid soft tissue tumors 11 were non-sarcomatous tumors with intermediate dignity. The negative predictive value of DNA cytometry was 97%: from 53 non-aneuploid soft tissue tumors only three were found to be sarcomas. Malignant soft tissue tumors demonstrate a significantly higher DNA-index (DI) and DNA grade of malignancy (DNA MG) than benign lesions. Our results show that DNA ploidy may serve as an additional parameter in problematic histological dignity assessments of soft tissue tumors. The histopathological grading levels of sarcomas show significantly different DI and DNA MG, so that DNA cytometry enables substantiated grading of soft tissue.