Unusual Malignant Thyroid Tumours - a Clinical Study of 20 Cases

The aim of this study is to assess late results of surgical treatment for primary non-Hodgkin lymphoma (PNHL), thyroid sarcomas (TS) and tumour metastases (TM) of the thyroid gland.

Materials and methods : Between January 1^st, 1990 and December 31^st, 2005, 12725 patients were surgically treated for various types of goitre. Malignant tumour was diagnosed in 617 (4.9%) cases, consisting of 597 (96.8%) patients with thyroid carcinoma and 20 (3.2%) with other tumours, which included 9 (1.5%) cases of PNHL, 9 (1.5%) cases of TM and 2 (0.2%) patients who showed TS.

Results : In the group of patients diagnosed with PNHL, variant B-cell lymphoma predominated (77.8%), and in cases of patients with TM renal cell carcinoma prevailed (77.8%). In all cases, hypo-echogenic nodules were observed in ultrasonography and cold nodules in scintigraphy. All patients were surgically treated with possible complementary chemotherapy and/or radiotherapy. At present, 5 patients with PNHL are alive - 43–93 (average of 63.8) months after the operation. Others have died within a period of 2 days to 3 months after the operation. Two patients with TM are alive - 19 and 46 (median 32.5) months after the operation. Others have died within a period of 3 to 62 (median 21) months after the operation. Patients with TS have died respectively 19 days and 13 months after the operation. Conclusions :

1. Patients with primary thyroid lymphomas should be approached individually using all available methods of treatment, including surgery and radiotherapy and/or chemotherapy.

2. Diagnosis of cold nodules in patients with oncological history should always arouse suspicion of metastases to the thyroid gland.

3. Diagnosis of non-thyroid cancer prior to surgery is difficult to obtain.

4. The need for surgery is usually based on local compression.