Endocrine Abstracts

Introduction: Increasing incidence of thyroid cancer might be a consequence of an increase detection of subclinical disease. The aim of this study was to compare the clinical and pathologic characteristics of nonincidentally discovered (NID) thyroid cancer with incidentally discovered (ID) on postoperative pathology.

Methods: A retrospective medical record review of 104 patients with thyroid cancer was performed. A group I of 69 patients with NID thyroid cancer was compared with a group II of 35 patients with ID thyroid cancer.

Results: At diagnosis the mean age was 51.5 years for the group I and 56.1 years for the group II (P=0.13). The rate of male was 18.8% in the group I and 14.3% in the group II (P=0.56). Hashimoto’s thyroiditis was present in 21.7 and 14.3% of patients in groups I and II respectively (P=0.65). Papillary tumor was the most frequent in both groups (87.0% in group I and 91.4% in group II). At TNM stage III and IV were present at a rate of 36.2 and 25.7% in the groups I and II respectively. There was no statistical difference in the mean size of tumor (P=0.13), focality (P=0.61), capsular involvement (P=0.20), and lymphovascular invasion (P=0.33). There weren’t lymph nodes metastasis in group II compared with a rate of 11.6% in group I (P=0.05). Radioactive iodine treatment was most frequent in group I (68.1 vs 45.7%) P=0.03.

Conclusions: There weren’t significant differences in the age, sex, presence of thyroiditis, size of tumor, focality, capsular, or lymphovascular invasion between the groups. There was an important rate of higher stage disease in the group II, nevertheless the ID thyroid cancer seems to be biologically less aggressive than NID, such as reported in other studies.