THE RELATIVE ROLES OF ENDEMIC GOITER AND SOCIOECONOMIC-DEVELOPMENT STATUS IN THE PROGNOSIS OF THYROID-CARCINOMA

BACKGROUND. It generally is accepted that the prognosis of thyroid car cinoma is more severe in areas in which goiter is endemic. It could be assumed that this prognosis also is less favorable in developing coun tries. METHODS. Clinical features and tumor histology of 1000 consecut ive patients were studied. Patient data from the endemic area (EPI) we re compared with those from the nonendemic area (NEA). In addition, pa tients from the years 1966-1981 (P1) were compared with those from 198 2-1991 (P2). It is obvious that the country's socioeconomic status and health care system improved be tween the mio periods. RESULTS, The an aplastic and follicular types of thyroid carcinoma were more frequent in EAs (14% and 42.13%, respectively) than in NEAs (6.25% and 38.40%, respectively). The frequency of the anaplastic carcinoma during P1 (16 .03%) decreased by half during P2 (7.79%), whereas the frequency of fo llicular carcinoma remained stable (35.85% and 40.46%, respectively). Clinically, more advanced stages (tumor size, local and distant dissem inations) were observed in the study country than in developed countri es. A clearcut improvement was observed during P2 whereas differences between the EA and NEAs were few. Survival rates (follicular and papil lary types only) were not found to be different between EAs and NEAs 5 -year survival: 81.44% and 75.32%, respectively; 10-year survival: 67. 93% and 69.52%, respectively). A significant (P < 0.01) increase was o bserved between P1 and P2 (S-year survival: 72.69% and 84.80%, respect ively; 10-year survival: 58.77% and 83%, respectively). CONCLUSIONS. C ompared with endemic goiter, low socioeconomic status appeared to be t he major factor accountable for the high prevalence of advanced stage cases and anaplastic carcinomas. Iodine deficiency appeared to play a specific role in the increased prevalence of follicular types of thyro id carcinoma. (C) 1998 American Cancer Society.