Relationship between histopathologic typing and morphonuclear assessments of 238 thyroid lesions. Digital cell image analysis performed on Feulgen-stained nuclei from formalin-fixed, paraffin-embedded materials.

Abstract

A digital cell image processor was used to compute 15 parameters on Feulgen-stained thyroid nuclei from 238 archival, i.e., formalin-fixed, paraffin-embedded thyroid lesions. The morphonuclear parameters were related to morphometric (nuclear area), densitometric (nuclear DNA content), and textural (chromatin pattern characteristics) features. With respect to development of a malignant condition, their variations were compared with the World Health Organization's International Histological Classification of thyroid tumors. The relationship between morphonuclear parameter assessments and tumor size and the presence or absence of metastasis at the time of diagnosis was also investigated: no relationship with respect to cytomorphonuclear assessments was found. Nuclear area and nuclear DNA content discriminated between simple multinodular goiters and multinodular goiters with adenomatous hyperplasia. In the same way, the mean parameter values describing the chromatin pattern of multinodular goiters were significantly distinct from those describing the chromatin pattern of adenomas and carcinomas. Furthermore, chromatin pattern descriptions made it possible to discriminate between cell nuclei from papillary carcinomas and follicular carcinomas, and further between follicular carcinomas and follicular adenomas. A marked variation was observed within individual cases of multinodular goiters, adenomas, and carcinomas, a feature suggesting that morphonuclear assessment is of limited value for the diagnosis of individual clinical cases. In contrast, these results show that morphometric, densitometric, and textural nuclear assessments are useful aids for thyroid tumor typing, adding interesting results with respect to thyroid tumor progression. Indeed, the primary findings demonstrate that nodules with adenomatous hyperplasia from multinodular goiter lesions and microvesicular adenomas more closely resemble follicular carcinomas than do simple multinodular goiters and normomacrovesicular adenomas. Such data might reflect a biologic progression from benign to malignant follicular thyroid lesions.