Sir

Alison Abbott's summary1 of the controversial cancer therapies of Luigi Di Bella accurately documents the fact that Di Bella has so far resisted efforts to have a committee of experts review his data, which raises further concerns that his combinations of a somatostatin analogue with vitamins and/or melatonin are not as effective as he claims.

The situation is more complex, however, as there is formal preclinical evidence indicating antineoplastic activity of somatostatin analogues such as octreotide and RC-160 in tumour model systems (reviewed in 23). These molecules appear to act by lowering systemic IGF-I levels (which may be relevant to cancer risk and prognosis4) and/or by activating specific growth inhibitory signal transduction pathways linked to specific somatostatin receptors which are expressed by neoplastic cells3. The preclinical evidence is sufficiently impressive, particularly in low tumour burden models, for both the US National Cancer Institute and the National Cancer Institute of Canada to be conducting randomized clinical trials to evaluate the activity of octreotide in the adjuvant treatment of breast cancer. A trial based at the Mayo Clinic comparing tamoxifen to the combination of tamoxifen and low dose octreotide in the treatment of advanced breast cancer showed no difference between treatment arms5.

Somatostatin analogues may or may not be shown in formal clinical trials to be useful in the treatment of specific neoplastic diseases, but it would be a mistake to use Di Bella's conduct to discredit rigorous research in this area.