Analysis of Primary Squamous Cell Carcinoma of Thyroid / 대한이비인후과학회지

ABSTRACT

BACKGROUND AND OBJECTIVES: Squamous cell carcinoma of thyroid is uncommon and accounts for less than 1% of all primary thyroid malignancies. Clinical features mimic the natural course of anaplastic carcinoma. This study reviewed the clinical course of six cases of primary squamous cell carcinoma of thyroid. SUBJECTS AND METHOD: We diagnosed six cases of primary squamous cell carcinoma of thyroid diagnosed from 1999 to 2006 at the College of Medicine Department of Pathology. Clinical data, treatment modality, and pathologic test results from medical records were retrospectively analyzed. RESULTS: We found five women and one man (with the mean age of 52.1 years) with squamous cell carcinoma of thyroid. The main presenting features were abruptly enlarging neck swelling and obstructive symptom. Pre-operative needle aspiration biopsy revealed papillary carcinoma in five cases. Only one patient was diagnosed as squamous cell carcinoma through pre-operative needle aspiration biopsy. Three patients had massive adjacent organ invasion, and four patients had lymph node metastasis according to the pathology review. There were no cases of distant metastasis at the time of treatment. All patients received surgery and adjuvant therapy (radiation therapy, chemotherapy, radioiodine therapy). Three patients are still alive with a mean follow up period of 47.3 months (range, 44-49 months). The other three patients died within one year post-operatively. CONCLUSION: Primary squamous cell carcinoma of thyroid should be considered in patients diagnosed with papillary carcinoma and who exhibit aggressive clinical behavior. Complete tumor resection and radiotherapy should be performed if thyroid squamous cell carcinoma is confirmed.