Subacute bulbar palsy as the initial sign of follicular thyroid cancer

Thyroid disease and the nervous system

Thyroid disorders are common in the general population and in hospitalized patients. Thyroid disease may present first with neurological complications or else may occur concurrently in patients suffering other neurological disorders, particularly those with an autoimmune etiology. For this reason neurologists will commonly encounter patients with thyroid disease. This chapter provides an overview of the neurological complications and associations of disorders of the thyroid gland. Particular emphasis is placed on conditions such as thyrotoxic periodic paralysis and myxedema coma in which the underlying thyroid disorder may be occult leading to a first, often emergency, presentation to a neurologist. Information about clinical features, diagnosis, pathogenesis, therapy, and prognosis is provided. Emphasis is placed on those aspects most likely to be relevant to the practicing neurologist and the interested reader is directed to references to good, recent review articles for further information.

Follicular thyroid carcinoma: From diagnosis to treatment

Unusual presentations with bone, lung or soft tissue metastases in initial diagnosis of follicular thyroid carcinoma have been reported occasionally. This implies how difficult it is to diagnosis this type of cancer at the pre-operative or intra-operative stage of treatment. Fine needle aspiration cytology has been shown to be an ineffective method for diagnosing vascular or capsule invasion of follicular thyroid cancer. Multiple frozen sections, usually 5 to 12 depending on the size of the tumor, can achieve a diagnostic accuracy of 98%. Clinical application of various gene expressions in thyroid follicular tumors by needle aspiration using in situ hybridization requires further investigation. Although radioactive iodide (131I) has been used as the standard treatment for follicular thyroid carcinoma with distant metastases, the effectiveness of 131I treatment for follicular thyroid carcinoma depends on the differentiation of cancer cells. The possibility of 131I for thyroid remnant ablation replacing a secondary operation for follicular thyroid carcinoma has been debated. Recent studies applied more expressions of sodium iodide symporters to attain the effect of 131I treatment and slow the proliferation of thyroid cancer cell which, in turn, slows the progression of follicular carcinoma. Consensus for the surgical procedures for the specific prognostic risks for follicular thyroid carcinoma is needed. Dedifferentiated, anti-angiogenic, or gene therapies for follicular thyroid cancer with distant metastases or anaplastic transformation comprise the principal directions in future research for this cancer.