INSULINOMA DISCOVERED DURING EARLY-PREGNANCY

Insulinoma is a rare tumour reported in 10 cases during pregnancy. In most cases, hypoglycaemia occurred during the first trimester and no f etal malformations were noted. We report a new clinical case of insuli noma diagnosed at 6 weeks of amenorrhoea in a 25-year-old woman. Surge ry performed at 17 weeks of amenorrhoea confirmed the presence of a 7 mm diameter endocrine tumour in the head of the pancreas and led to a cure. The pregnancy continued without complications, and at 35 weeks t he patient gave birth to a 3.5 kg infant with no malformation. This ca se was investigated in terms of a possible physiopathological cause of insulinoma during pregnancy. There is good evidence that insulin secr etion increases rapidly from the beginning of pregnancy because of bet a-cell proliferation and enhanced beta-cell sensitivity to glucose sti mulus as a result of hormonal changes, i.e., prolactin and/or placenta l lactogen secretion. Moreover, some studies have suggested that insul in sensitivity is enhanced during early pregnancy. Taken together, the se phenomena may explain why insulinoma occurs early during pregnancy. Although repeated hypoglycaemia has caused teratogenic effects in ani mal models, no fetal malformation has been described in previous repor ts of insulinoma during pregnancy, whether cured or not. This is in ag reement with prospective studies in insulin-treated pregnant diabetic women showing no correlation between hypo glycaemia and malformations. These results are encouraging with respect to such pregnancies which, however, require careful supervision.