Effect of type 2 diabetes and antihyperglycemic drug therapy on signs of tumor invasion in papillary thyroid cancer.

This retrospective study investigated the association between worrisome pathological features of papillary thyroid cancer indicative of invasion and type 2 diabetes, as well as antihyperglycemic drug therapy for diabetes.The records of 14,167 patients who had undergone primary surgery for thyroid cancer were retrospectively reviewed and screened for concomitant diabetes. The diabetic and nondiabetic groups were age and gender matched, and further stratified by treatment, including five single antihyperglycemic drugs.The study population comprised 942 patients, including 471 patients each with and without diabetes. The rate of worrisome pathological features was higher in diabetic patients than in nondiabetic patients (49.26% cf. 30.57%, P < 0.001), mainly reflected by extrathyroidal extension (34.82% cf. 5.94%, P < 0.001) and lymph node metastasis (42.68% cf. 33.55%, P < 0.001). The number of lymph node metastases in those treated with acarbose (0.32) was significantly lower compared with groups given any of the other four antihyperglycemic drugs (ranging from 1.51 to 2.15; P = 0.001 to 0.05).Papillary thyroid cancer complicated with type 2 diabetes has a higher risk of invasive tumor growth. Compared with other antihyperglycemic drugs, patients with acarbose had the lowest risk of aggressive tumor growth. These results may evoke pathophysiological hypotheses to be explored in preclinical and clinical studies.