Objective malignancy grading of squamous cell carcinoma of the lung. Stereologic estimates of mean nuclear size are of prognostic value, independent of clinical stage of disease.

Abstract

The prognostic value of quantitative histopathologic parameters was evaluated in 55 consecutively treated patients with operable lung carcinoma of squamous (N = 39) and mixed, adenosquamous (N = 16) cell type. Patients alive were followed for at least 12 years. Using a projection microscope and a simple test system in fields of vision systematically selected from the whole tumor area of one routine section, five quantitative histopathologic variables were estimated: the mean nuclear volume, the mean nuclear profile area, the density of nuclear profiles, the volume fraction of nuclei to tissue, and the number of mitotic profiles per 10(3) nuclear profiles. For each patient, information was recorded regarding sex, age at diagnosis, and clinical stage of disease. Single-factor analyses showed that a favorable prognosis was associated with early clinical stages (Stages I and II) and young age (P < or = 0.03), and that females tended to do better than males (P = 0.09). Estimates of the mean nuclear volume were of prognostic significance (P = 0.02), small nuclei being associated with the worst prognosis. In a multivariate Cox analysis, clinical stage, age, and mean nuclear volume were found to be parameters of significant, independent prognostic value. The present feasibility study indicates that estimates of the mean nuclear volume are of prognostic value, independent of the clinical stage of disease. This quantitative histopathologic variable is highly reproducible and easily obtained using an unbiased stereologic method. Thus, the mean nuclear volume may be a parameter of future importance in the clinical management of patients with carcinoma of the lung.