DIFFERENTIAL-DIAGNOSIS OF MALIGNANT AND REACTIVE CELLS FROM SEROUS EFFUSIONS - IMAGE AND TEXTURE ANALYSIS STUDY

The interrelationship of textural primitives which define morphologica l texture can be estimated by quite different descriptors; the discrim inant value of which varies considerably. In the present study three d ifferent approaches to the texture analysis of nuclear chromatin were assayed to correctly allocate 332 cells from a pool obtained from sero us effusions (six malignant mesotheliomas, six reactive mesothelial pr oliferations and five pleural metastases of lung adenocarcinoma). In a ll cases, initial cytological diagnosis posed considerable problems an d final diagnosis was established by histologic examination of surgica l specimens. The three approaches were based on binarization of the im age obtained by edge detection, gradient analysis and pattern spectrum by morphological opening-closing, respectively. Characteristics affor ded by each method were: (a) spatial distribution of heterochromatin, besides geometric features, (b) features related to transitions and co ntrast between dark and light chromatin primitives, and (c) granulomet ric characteristics of the theoretically biphasic heterochromatin-euch romatin image defined by mathematical morphology. The three methods we re applied to the raw grey-tone image and did not require interactive handling. Although each of the three approaches yielded relatively sat isfactory results, with percentages of well-classified cells in the te st set ranging from 61.45 to 67.47, the best results (78.31% of well-c lassified cells) were obtained taking into consideration the three typ es of variables (area, 2nd opening, 5th closing, and S.D. of the ampli tude image). A point to be stressed is the considerably high proportio n of correctly-allocated reactive mesothelial cells (82.0%) in a field where subjective assessment commonly yields rather poor results. Neve rtheless, classification yielded 14.8% and 3.3% false positives as ade nocarcinomatous and malignant mesothelioma cells, respectively. In the theoretical situation devised in the study, results on a cell-by-cell basis are encouraging and suggest that a textural approach might be u seful in a dedicated expert system or on a more real case-by-case basi s. Copyright (C) 1996 Elsevier Science Ireland Ltd.