ABSTRACT
Objective To study the clinicopathology characteristics of chronic lymphocytic thyroiditis (Hashimoto's thymiditis, HT) with occult papillary thyroid carcinoma (occult PTC) in order to improve its diagnostic and therapeutic accuracy. Methods A restrospective analysis was done on the clinical materials of 28 cases of HT with occult PTC from July 1999 to July 2005. All cases were confirmed by operation and pathologic biopsy. Clinical and gross findings were collected. All HE slides were reexamined and immunostains for CK19, galectin-3,and bcl-2 were performed (Envision method). Results In total 189 cases of chronic lymphocytic thyroiditis,28cases (14.8%,28/189)had coexistent occult papillary thyroid carcinoma. There were 19 females and 9 males with median age of 36.7 years old. Normal TSH presented in 11cases (39.3%), high in 8 cases(28.6%), and low in 9cases (32.1%). All tumor diameter was counted for <0.8 cm, 16 cases (57.1%) tumor diameter 0.2～0.5 cm, 12 cases (42.9%) >0.5 cm. Coarse calcification was seen in 6 cases(21.4%) in color ultrasonic exam and CT scans. Follow-up data showed that 28 patients were all alive with no evidence of recurrence or metastasis for 2 to 7 years by December 2007. Conclusion There are no special clinical characteristics in coexistent HT with occult PTC.Coarse calcification in HT in the group of middle-aged women increase the likelihood of the diagnosis. But the diagnosis depends on pathology. Because of the high incidence of occult PTC in HT population, it would be necessary to keep an eye on this particular type of thyroid carcinoma, and multiple sampling in suspected area of HT specimen is advised in the hope not to miss any small tumor in clinical practice.