DIAGNOSIS, TREATMENT, AND OUTCOME OF FOLLICULAR THYROID-CARCINOMA

Background. There have been numerous studies concerning the diagnosis, treatment, and prognosis of patients with papillary thyroid carcinoma , but relatively few addressing patients with follicular carcinoma. Me thods. The authors analyzed their experience with 65 patients who unde rwent 96 thyroid operations for pure follicular thyroid carcinoma from 1956 to 1990.Results. The patients were 43 women and 22 men with a me an age of 45 years who were followed postoperatively for a mean of 10. 4 years. Fifty-two patients (80%) were seen initially with a solitary thyroid nodule, and 24 (37%) had symptoms at presentation. Median tumo r size was 2.2 cm. Fine-needle aspiration biopsy was performed in 20 p atients, revealing a follicular neoplasm in 18 patients (90%) and an i nadequate specimen in 2 patients. Nineteen patients received thyroid-s timulating hormone (TSH)-suppressive thyroid hormone therapy for an av erage of 4.5 months before surgery; tumor size remained the same in 10 patients (53%), increased in 5 (26%), and decreased in 2 (11%). At pr esentation, six patients had lymph node involvement, three had locally invasive tumors, and two had distant metastases. Initial operative tr eatment was lobectomy in 32 patients (49%), total thyroidectomy in 15 patients (23%), lobectomy plus contralateral partial or subtotal lobec tomy in 11 patients (17%), and lesser procedures in 7 patients (11%). Twenty-nine patients had a completion total thyroidectomy, so that fin al surgical treatment consisted of total thyroidectomy in 44 patients (68%). Among 39 patients having intraoperative frozen section, only 3 (8%) were correctly diagnosed as having cancer. Permanent complication s occurred during 3 of the 96 operations. Three patients (5%) have die d of thyroid cancer (one with anaplastic transformation) since thyroid ectomy, and two are living with distant metastatic disease. Conclusion s. Patients with follicular thyroid cancer, when first examined, usual ly have solitary thyroid nodules that are follicular neoplasms by aspi ration cytology, and these nodules fail to regress in response to TSH- suppressive therapy. Frozen section rarely aids in management. The pre ferred treatment for follicular neoplasms is lobectomy followed by com pletion total thyroidectomy for histologically proven carcinomas large r than 1.0 cm. Total thyroidectomy allows use of thyroglobulin and rad ioiodine scanning to detect and treat metastatic disease. Complication s of thyroidectomy were uncommon, and the mortality rate in treated pa tients was relatively low.