Review of thyroid cancer cases among patients with previous benign thyroiddisorders

A previous register linkage study showed an increased risk of thyroid cance r among patients previously discharged from a hospital with a diagnosis of a benign thyroid disorder. In this study, we have reviewed all available me dical records, first to validate the earlier result and second to describe the symptomatology of patients with a history of benign thyroid disorder pr ior to the cancer diagnosis. The previous study identified 189 patients wit h a benign and subsequent malignant thyroid disorder. Medical records were obtainable for 156 of these patients and were reviewed. For 104 patients, b enign and malignant thyroid diseases were metachronous (a clearly separated disease history of the benign and malignant diseases), and for 48 patients synchronous. In 4 cases, thyroid cancer could not be confirmed. Among pati ents with metachronous thyroid disorders, all major benign thyroid disorder s were represented including hot nodules, diffuse and multinodular toxic an d nontoxic goiter. Symptoms preceding diagnosis of thyroid cancer included growth of goiter/nodules, globulus, strider, hoarseness, and metastasis. No major differences were found among patients with metachronous and synchron ous benign and malignant thyroid disorder, apart from the fact that all met astases were found among metachronous cases. This study confirmed the concl usion that patients with a previous history of goiter or nodules have an in creased risk of thyroid cancer. However, thyroid cancer still occurs too in frequently to warrant screening in all patients with a previous history of goiter or nodules.