Meta-Analysis of Squamous Cell Carcinoma of Thyroid

Shim, Hyun Seok; Kwon, Oh Jin; Ko, Joon Seok; Park, Jung Je; Kim, Jin Pyeong; Jeong, Chan Ryeul; Woo, Seung Hoon

Abstract

BACKGROUND AND OBJECTIVES
Primary squamous cell carcinoma (SCC) of thyroid is an unusual tumor, accounted for approximately 1.1% of all neoplasms of the thyroid gland. It is highly lethal, like anaplastic thyroid carcinoma, in terms of aggressive clinical behavior. In the literature, the best treatment of this tumor is by surgery and the use of combination therapy that includes postoperative radiation, chemotherapy and radioiodine therapy; however, the effect of treatment is very poor. This study aims to identify the clinical features of SCC of thyroid, and to devise a better treatment method.
SUBJECTS AND METHOD
Journals citing SCC of thyroid were identified from Pubmed, Korea Med, and Google and the clinical records reported therewithin from 1990 to 2013 were reviewed. A total of 40 patients were analyzed from 21 well-organized papers by searching the following keywords: squamous cell carcinoma, primary, thyroid, excerpt of the patient's age, sex, clinical features, pathologic findings, therapy, course and prognosis.
RESULTS
We analyzed the treatment results of 40 patients from a total of 21 papers. Patients, consisting of 17 men and 23 women, were found in the age range of 24-88, with the mean age of 63.2. The follow-up period ranged from one to 96 months, with the mean being 15 months, and the size of the mass varied from 1 cm to 15 cm. Histopathologically, we found 13 patients with only SCC mixture of SCC and 22 patients with papillary thyroid carcinoma (PTC). Each of the following diseases were identified with one patient: a mixture of SCC and Hashimoto thyroiditis, a mixture of follicular thyroid carcinoma (FTC), SCC and FTC and mixed Hurtle cell cancer, SCC and PTC and mixed Hashimoto thyroiditis, and SCC, PTC with mixed insula cancer. Thirty-two patients underwent total thyroidectomy, and 30 patients underwent total thyroidectomy accompanied by neck dissection. Twelve patients received postoperative radiation therapy, and five patients received postoperative chemotherapy. Nineteen patients were observed without recurrence of the disease, and ten patients were found to be in stage III or less.
CONCLUSION
SCC of the thyroid showed aggressive clinical characteristics, however, good results can be expected with early diagnosis and treatment. If tumor is found only within the thyroid, we expect good therapeutic results after the same treatment as PTC.