Thyroid Research Thyroid Research Archive Thyroid Cancer

Among patients with Hurthle-cell carcinoma, older age and large tumor size predict a poor outcome

(July 2003)

The background of the study. Hurthle-cell (large granular mitochrondion-rich) tumors of the thyroid are uncommon, and little is known about their characteristics. This study examined the relationships between the clinical and pathologic features of Hurthle-cell tumors and patient outcome.

Patient characteristics and treatment. The study subjects were 38 patients with a benign Hurthle-cell adenoma and 89 patients with a Hurthle-cell carcinoma; approximately two thirds of the patients in each group were women. The tumors were considered malignant if there was invasion of the capsule of the tumor or of blood vessels. The average size of the adenomas was 2.9 cm, and that of the carcinomas was 4.3 cm. Twenty-nine patients (33 percent) had multiple microscopic foci of carcinoma within the thyroid. Thirty-five patients (39 percent) in the carcinoma group underwent unilateral surgery and 54 (61 percent) bilateral surgery; many also received radioactive iodine (I-131).

The results of the study. The patients with an adenoma were followed for 9 years and those with a carcinoma were followed for 10 years. No patient in the adenoma group died as a result of the tumor, whereas 36 patients (40 percent) in the carcinoma group died as a result of the tumor. The 20-year tumor-related mortality rate was 40 percent.

Forty-seven patients (53 percent) had progression of their disease after initial treatment. Factors associated with progression were age >45 years, larger tumor size, extrathyroidal invasion, and local and distant tumor spread. These factors, more extensive surgery, and radiation therapy were associated with an increased risk of tumor-related mortality.

The conclusions of the study. Among patients with Hurthle-cell carcinoma of the thyroid, those who are older, have large tumors, and have extensive disease at diagnosis are most likely to have disease progression and die from their disease.

The original article. Lopez-Penabad L, Chiu AC, Hoff AO, Schultz P, Gaztambide S, Ordonez NG, Sherman SI. Prognostic factors in patients with Hurthle cell neoplasms of the thyroid. Cancer 2003;97:1186-94.