A patient with a metastazing functional islet cell tumour suffering from severe hypoglycaemia was treated with streptozotocin. Four intravenous injections of 1.5 g streptozotocin each were administered in 4 to 6 days intervals. After the 4th injection there were no further episodes of hypoglycaemia, parenteral glucose administration could be stopped and blood sugar and plasma insulin, showing concentrations of up to 405 μU/ml before treatment, reached normal levels. The tumours in the pancreas disappeared and the liver metastases decreased in size and number as judged by arteriography.
A hypothesis for the mechanism of action of streptozotocin is proposed. The glucose moiety is considered to facilitate a high affinity to the islet cells whereas the N-methyl-nitrosourea residue serves the active antitumour part of the molecule.
