Incidence and Risk Factors of Thyroid Malignancy in Patients with Toxic Nodular Goiter

Abstract

Background. Although hyperfunctioning thyroid disorders were thought to be protective against malignancy, some recent studies reported a high incidence of incidentally discovered cancer in patients with hyperfunctioning benign thyroid disorders. We performed this study to estimate the incidence and predictors of malignant thyroid disease in patients with toxic nodular goiter (TNG). Patients and Methods. The data of 98 patients diagnosed with TNG were reviewed (including toxic multinodular goiter SMNG and single toxic nodule STN). The collected data included patients age, gender, systemic comorbidities, family history of thyroid malignancy, previous neck radiation, type of disease (multinodular or single), size of the dominant nodule by the US, operative time, and detection of significant lymph nodes during operation. Based on the histopathological analysis, the cases were allocated into benign and malignant groups. Results. Malignancy was detected in 21 patients (21.43%). Although age distribution was comparable between the two groups, males showed a significant increase in association with malignancy. Medical comorbidities and family history of cancer did not differ between the two groups. However, TMNG showed a statistically higher prevalence in the malignant group. Operative data, including operative time and lymph node detection, were comparable between the two groups. On regression analysis, both male gender and TMNG were significant predictors of malignancy. Conclusion. The presence of thyroid hyperfunction is not a protective factor against malignancy, as malignancy was detected in about 1/5 of cases. Male gender and TMNG were significant risk factors of malignancy in such patients.

Risk of malignancy in cytologically indeterminate thyroid nodules harboring thyroid stimulating hormone receptor mutations

“…Though it is often taught that toxic thyroid nodules are benign, and hyperthyroidism is correlated with a low risk of thyroid cancer, several surgical series show a higher-than-expected incidence of thyroid cancer. Mohamed et al reported a 21% malignancy rate in patients who underwent surgery with toxic multinodular goiter or toxic adenomas, though there was not specification of the presence of thyroid cancers within the autonomous thyroid tissue (9). Tam et al found a similar 19% malignancy rate in toxic nodular goiter resections with specification that half (9.5%) of these malignancies arose from the autonomous nodule/s (10).…”

“…Mohamed et al. reported a 21% malignancy rate in patients who underwent surgery with toxic multinodular goiter or toxic adenomas, though there was not specification of the presence of thyroid cancers within the autonomous thyroid tissue ( 9 ). Tam et al.…”