[Epidemiological correlations of insulin resistance and salivary gland tumors].

BACKGROUND

The metabolic syndrome develops on the basis of peripheral insulin resistance. It is a continuously progressing metabolic disorder, which concludes finally into serious diseases. Type-2 diabetes, cardiovascular disease and--according to the recent literature--malignancies are the most important consequences. A well-known fact, that metabolic disorders; such as diabetes and obesity, can deeply influence the structure and function of the salivary glands. Considering these data, the question arises; is there any correlation among insulin resistance, type-2 diabetes and salivary gland tumors?

OBJECTIVE

A retrospective epidemiological examination was performed to analyze the correlations between salivary gland tumors and insulin resistance states (type-2 diabetes and metabolic syndrome).

METHODS

Data of 438 patients were analyzed in the Maxillofacial Surgery Clinic of the Semmelweis University. In 224 cases salivary gland tumors were surgically removed. In 214 control cases, bone replacement, or artificial root implantation was the intervention. Known, treated and newly diagnosed diabetic cases were included in the DM group. Cases exhibiting at least 3 of the 5 criteria of the metabolic syndrome composed the MS group. The remaining cases were included in the non-DM/non-MS group. The frequencies of cardiovascular diseases and of primary tumors at other sites were registered in the different groups.

RESULTS

Type-2 diabetes was significantly more frequent in the tumorous group (22.8%) than in the controls (6.5%) (p < 0.001). Similarly, the metabolic syndrome was much more frequent among the tumorous cases (31.3%) as compared with the control group (7.9%) (p < 0.001). The rate of cardiovascular diseases was significantly higher in the DM and MS subgroups of the tumorous patients (15.6% and 17.1%, respectively) as compared with the controls (5.6%) (p < 0.05 and p < 0.01, respectively). The rate of primary tumors of other sites, as concerns both tumors overall and malignancies, was significantly higher among the salivary gland tumorous cases (17.8% and 8.9%, respectively) than among the controls (8.4% and 2.8%, respectively) (p < 0.01 and p < 0.05, respectively). In the DM and MS subgroups of the tumorous cases the rate of primary tumors was even higher (28.0% and 22.9%, respectively), however, that for the non-DM/non-MS subgroup was similar to that for controls (9.7).

CONCLUSIONS

Considering the present results and the literature data a better control of insulin resistant states seems to be necessary, not only to reduce the cardiovascular risk, but also to prevent tumor promotion.