INSULIN AND C-PEPTIDE RESPONSE TO ORAL GLUCOSE IN PATIENTS WITH BREAST CANCER

Insulin is the common denominator of some conditions (obesity, low-fiber diet, etc.) all known as etiologic risk factors for breast cancer. There are only few studies concerned with hyperinsulinemia in breast cancer patients, and none of these include insulin and C-peptide responses to glucose. In this study we aimed to determine insulin and C-peptide responses to oral glucose in patients with breast cancer. Study group consisted of 29 women with breast cancer and mean age of 50 (range 24-70); control group was formed by 29 healthy volunteer women with similar mean age and mean body mass index values. All subjects underwent an OGTT modified as follows: After a fasting period of 12 hours preceeded by a normal diet, blood samples for glucose, insulin and C-peptide were obtained and 100 gr glucose was immediately given orally. Further samples for glucose, insulin and C-peptide analysis were taken after 60 and 120 minutes following glucose ingestion. No serum glucose differences was found between two groups at zero, 60 and 120 minutes assays (p>0.05). Similarly there was no insulin and C-peptide differences at the 0 minute assays (p>0.05). Mean insulin and C-peptide levels in the breast cancer group was significantly higher than the control subjects (p<0.05). Although 120. minute insulin and C-peptide values were also higher in the breast cancer group, this difference was not statistically significant (p>0.05). Our results showed that hyperinsulinemia developed after glucose ingestion. Considering that insulin is effective in cell growth and differentiation, it was concluded that insulin may play a role in the development of breast cancer. Further work, with larger series are necessary to provide more conclusive data.