Neuroendocrine tumors are a rare and heterogeneous group of tumors with a variety of primary origins and variable aggressiveness. Platinum-based chemotherapy has been the cornerstone of treatment for the poorly differentiated tumors. However, well-differentiated neuroendocrine tumors are quite chemoresistant and therapy options are limited. Octreotide analogs and tyrosine kinase inhibitors are widely acceptable treatments due to substantial efficacy and tolerable toxicity.
Cap/Tem is an oral, well-tolerated treatment for the management of the well-differentiated NETs. The toxicity profile is superior compared with streptozocin-based regimens. The recent review by Elais et al, concluded that Cap/Tem chemotherapy appears to be multiple times more efficacious than tyrosine kinase inhibitors and also less toxic. Taking into account that chemotherapy so far has produced poor results against non-pNET tumors, the Cap/Tem regimen proved effective in all neuroendocrine subtypes including GI non-pNETs and bronchial carcinoids. Prospective trials are needed to compare Cap/Tem with streptozocin and tyrosine kinase inhibitors in order to establish a standard of care.
NCCN says that no consensus had been established on chemotherapy for neuroendocrine cancers, but it lists this regimen among those “that are commonly used”. This is a recommendation as category 3.
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