Gastrointestinal cancer refractory to chemotherapy: a role for octreotide?

Abstract

Although octreotide has been shown to inhibit the growth of gastrointestinal (GI) tumors in vitro and in vivo, preliminary clinical trials have reported disappointing results for this somatostatin analog in patients with GI cancers. The results of these trials probably reflect the difficulty in assessing the therapeutic potential of an agent such as octreotide in GI cancers. Thus, it is possible that treatment with octreotide could be useful in the stabilization of disease if it is associated with an improvement in survival. On the basis of these considerations five randomized trials were carried out to evaluate the therapeutic potential in patients with GI cancers. Four trials (one in patients with colorectal carcinoma and three in patients with carcinoma of the pancreas) did not show any advantage of octreotide in untreated patients; in contrast, one trial reported that octreotide prolonged survival in patients with GI cancers refractory to chemotherapy. Some clinical features of the latter study (treatment with chemotherapy, different schedules) may explain these conflicting results. Although data from randomized trials suggest that octreotide is not effective in untreated asymptomatic advanced GI cancer patients, further studies are warranted to assess the efficacy of octreotide in chemotherapy refractory patients in order to clarify the impact of octreotide in terms of not only survival but also on the patients' quality of life.