Object: Carcinoid tumors are rare and have generally been regarded as indolent neoplasms. Systemic disease is often incurable; however, patients may live years with this disease. Furthermore, metastatic brain lesions are extremely uncommon. As such, few series have examined outcomes and prognostic factors in those with brain involvement.
Methods: The authors performed a retrospective review of patients who underwent primary treatment at Mayo Clinic in Rochester, Minnesota, for metastatic carcinoid tumors to the brain between 1986 and 2011. Progression-free survival (PFS) and overall survival (OS) were analyzed using Kaplan-Meier statistics. Cox proportional hazards were used to determine predictors of survival.
Results: Fifteen patients underwent primary treatment for metastatic carcinoid tumors to the brain between 1986 and 2011. Their mean age was 58 ± 12 years. Eighty percent (n = 12) of patients underwent surgery, whereas 2 received stereotactic radiosurgery and 1 had whole-brain radiation therapy (WBRT) as the primary treatment. The median follow-up duration was 19 months (maximum 124 months). Systemic disease progression occurred in 73% and was the leading cause of death in known cases, while intracranial disease recurred in 40%. The median PFS and OS were 21 and 19 months, respectively. The use of adjuvant WBRT correlated with improved PFS (HR 0.15, CI 0.0074-0.95, p = 0.044). Those who underwent surgery as primary modalities trended toward longer progression-free intervals (p = 0.095), although this did not reach significance.
Conclusions: Metastatic carcinoid disease to the brain appears to have a worse prognosis than that of other extracranial metastases. Although there was a trend toward a survival advantage in patients who underwent surgery and WBRT, further study is needed to establish definitive treatment recommendations.