MEDULLARY-THYROID CARCINOMA - SEARCH FOR HISTOLOGICAL PREDICTORS OF SURVIVAL (109 PROBAND CASES ANALYSIS)

A group of 13 pathologists belonging to the French Calcitonin Tumor St udy Group (GETC: Groupe d'Etude des Tumeurs a Calcitonine) examined th e histological slides and medical records of 109 proband cases of medu llary thyroid carcinoma (MTC) diagnosed on clinical features. The case s belonged to the various forms of the disease (80 sporadic and 29 fam ilial MTC). The aim of the study was to detect histological predictors for survival by comparing morphological data from patients killed by the disease versus the others. Twenty-seven histological parameters we re considered, including cellular heterogeneity, shape of the cells, a nd cytoplasmic characteristics. Other parameters such as sex, age, and phenotype of the disease were also studied. First, predictive paramet ers of interest on survival function were selected by univariate analy sis (Mantel-Cox test). Then, the extracted parameters were tested in a multifactorial analysis using the Cox's forward stepping proportional hazard model. Five parameters were significantly associated with a lo wer survival function: presence of necrosis in the tumor (P = .001), s quamous pattern (P = .002), age over 45 years (P = .004), presence of oxyphil cells in the tumor and absence of cells with intermediate cyto plasm (P = .025), less than 50% of calcitonin immunoreactive cells in the tumor (P = .04). Copyright (C) 1998 by W.B. Saunders Company.