Hyperthyroidism and concurrent thyroid cancer.

AIMS AND BACKGROUND

The aim of this study was to analyze the frequency of coexisting hyperthyroidism and thyroid malignancy in endemic goiter areas and review the current literature on the subject.

METHODS

During the period January 1984 to June 1998, 1853 patients were examined for hyperthyroidism at the Spedali Civili Hospital of Brescia, Italy; 512 (27.6%) subjects underwent surgery. Of these patients 108 (21%) had Graves' disease, 251 (49%) multinodular toxic goiter (MTG) and 153 (30%) uninodular toxic goiter (UTG).

RESULTS

Malignancy was found in 24 (4.7%) patients: 19 females and 5 males with a mean age of 52.2 years (range, 21-76 years). The frequency of cancer in Graves' disease was 6.4%, 5 females and 2 males; in MTG 3.9%, 2 females and 8 males, and in UTG 4.4%, 7 females and 1 male.

CONCLUSIONS

Our data confirm previous reports on the frequency of thyroid cancer in hyperthyroidism. This association is more relevant than previously suspected. The frequent coexistence of hyperthyroidism and neoplasia, demonstrated by our study and the most recent literature, underlines the importance of studying and excluding the possibility of neoplastic degeneration by means of a systematic approach.