PATHOLOGY RESEARCH AND PRACTICE © Urban & Fischer Verlag http://www.urbanfischer.deljournalslprp Stereologically Estimated Mean Nuclear Volume and Histopathologic Malignancy Grading as Predictors of Disease Extent in Non-small Cell Lung Carcinoma OzgOI Sagol, Aydanur Kargl and Sermin Ozkal Dokuz EylOI Uni ve rsity School of Medicine, Department of Pathology, Izmir, Turkey Summary The aim of this study was to investigate the value of the architectural grade, cytologic atypia, mitotic counts and stereologically estimated mean nuclear volume in pre- dicting the stage of disease in non-small cell lung carci- nomas. Hematoxylin-Eosin-stained sections from 53 non-small cell lung carcinomas were evaluated in terms of the morphologic and morphometric features mcn- tioned above. Mean nuclear volume was estimated stereologically. Operable and inoperable tumor stages were compared concerning the parameters examined. There was no significant difference between operable and inoperable tumor stages in terms of the architec- tural grade in both squamous cell carcinomas and ade- nocarcinomas, although we found a positive correlation between architectural grades and increasing stages in SCC. Significant differences wcre found concerning atypia, mitosis grades, and the scorc combining both variables (C2) when comparing operable with inopcra- ble tumor stages in squamous ccll carcinomas but not in adcnocarcinomas (Chi square, p = 0.013, P = 0.008 and p = 0.008 for squamous cell carcinomas respectively). The mean nuclear volumes of tumor cells in both squa- mous cell carcinomas and adenocarcinomas showed statistically significant differences between operable and inoperable stages (p = 0.05 and 0.02 respectively). We conclude that an assessment of the proliferative activity and the degree of cell atypia, as well as an esti- mation of mean nuclear volume in conjunction with ar- chitectural gradc, may contribute to predicting the ex- tent of the disease and outcome, particularly in SCC. On the other hand, only mean nuclear volume appears to be a useful parameter for determining the course of the disease in adenocarcinomas. Pathol. Res. Pract. 196: 683-689 (2000) Key words: Non-small cell lung cancer Histologic grading Stereology Introduction Non-small cell lung carcinomas (NSCLC) comprise about 75% of lung cancers, including squamous cell carcinomas, adenocarcinomas, and large cell carcino- mas . It has been demonstrated that the stage of the dis- ease is the most use ful criterion for predicting survival in NSCLC [3, 16]. However, even with a given individ- ual morphologic type and stage, NSCLCs exhibit a very heterogeneous picture regarding the course of disease and outcome. This may partly be due to the differences in the malignant potential of the lesions, which is thought to be associated with the degree of histologic differentiation [20-22/. The unpredictable clinical behavior of tumors has stimulated the request for biologic factors evaluated by morphologic and morphometric mean s. Some of these factor s, which are considered important, arc histologic type, tumor grade, mitotic activity, nuclear pleomor- phism, nuclear and nucleolar morphometric features. The impact of these variables on the clinical behavior of the tumors is controversial [22}. Address for correspondence: bzgOI Sogol, Dokuz Eyllil Uni versitesi, TIp Fakliltesi, Paloloji ABD, 35340 inciralll Izmir, Turke y. fax: ++90 23212777 7274. E-mail: ozgu1.sagol@deu.edu.tr 0344-0338/2000/196/1 0-683 $15.0010