Atypical Cerebral Carcinoids Treated with Hippocampal-Sparing Whole Brain Radiotherapy

Central nervous system (CNS) metastases of atypical carcinoid tumors are exceptionally rare. Isolated studies suggest a survival benefit in patients who receive whole-brain radiotherapy (WBRT); however, it has been known to have detrimental effects on long-term memory and executive function. Here, we present a case of a patient initially diagnosed with stage IIB bronchopulmonary carcinoid who later developed hepatic and intracranial metastases despite receiving adjuvant systemic therapy over a two-year period. She underwent hippocampal-sparing WBRT (HS-WBRT), receiving 30 Gy in 10 fractions via daily image-guided photon therapy using two coplanar arcs. Subsequent clinical evaluations and magnetic resonance imaging (MRI) of the brain at 11 months post-treatment demonstrated a decrease in the size and number of brain metastases, with the patient reporting stable memory and cognition. This case demonstrates the efficacious delivery of palliative HS-WBRT in a patient with a rare presentation of brain-metastatic atypical carcinoid, conferring effective local control and preservation of cognition. Multi-therapy regimens that incorporate HS-WBRT may be considered for improved disease control and quality of life. Further investigation of systemic agents, and possible molecular targets that could confer greater efficacy against treatment-progressive atypical carcinoids, is also warranted.