Cognitive impairment associated with carcinoid syndrome.

OBJECTIVES: To evaluate the cognitive performance of patients with carcinoid syndrome (CS) compared with population norms and cancer patients with non-neuroendocrine (non-NET) liver metastases. BACKGROUND: The release of serotonin into the systemic circulation from metastatic small bowel neuroendocrine tumors (SB NET) causes CS. Many patients with CS followed in a multidisciplinary NET clinic seemed to exhibit a unique cognitive impairment. Because serotonin is known to influence a range of cognitive function, the question arouse as to whether cognitive impairment is another manifestation of CS. METHODS: Patients were recruited from the multidisciplinary NET and the hepatobilary cancer clinics at the cancer center. The CS group consisted of patients with proven SB NETs metastatic to liver; the cancer comparison group consisted of patients with liver metastases from non-NET cancer. All completed a self-reported cognitive questionnaire and a battery of 6 standardized neurocognitive tests. Both groups were compared to age/sex/educational-matched norms. RESULTS: Thirty-six patients with CS and 20 with non-NET metastases were enrolled. Patients with CS reported greater cognitive dysfunction in all cognitive domains than both norms and the comparison cancer group. On cognitive testing, patients with CS demonstrated weakness in initiation, processing speed, visual memory, cognitive efficiency, and delayed verbal recall compared with norms. Although the patients with non-NET cancer also demonstrated some cognitive dysfunction compared with norms, the patients with CS did significantly worse on delayed recall (P = 0.03) and marginally slower on speeded mental flexibility (P = 0.097) compared with patients with non-NET cancer. CONCLUSION: This study confirmed our clinical observation that patients with CS suffer from cognitive impairment that is different from the non-NET cancer group and population norms.

Impairment of cognitive function reported by patients suffering from carcinoid syndrome.

BACKGROUND: Carcinoid syndrome (CS) is characterized by symptoms of diarrhea, flushing, bronchospasm, and valvular heart disease. It has been our impression that patients with CS also exhibit features of cognitive impairment. The purpose of this pilot study was to evaluate if symptoms of cognitive impairment were reported by patients with CS. METHODS: Patients with proven CS completed a 38-question multiple-ability self-report questionnaire (MASQ) to assess symptoms in five cognitive domains: language skills, attention/concentration (A/C), visual-perceptual function, visual memory, and verbal memory. Patients subsequently underwent neurocognitive assessment using a battery of six standardized tests. Results of the MASQ and the cognitive test were compared to published results for healthy individuals. RESULTS: Twenty-one patients with CS were studied. MASQ symptom scores were higher than published norms in all five cognitive domains. Patients reported greatest difficulty with verbal memory (mean +/- SD = 2.74 +/- 0.5), followed by A/C (2.41 +/- 0.65), language (2.31 +/- 0.55), visual memory (2.30 +/- 0.65), and visual-perceptual function (2.17 +/- 0.59). In contrast, neurocognitive tests for verbal memory immediate recall, visual memory, language, and executive function were within the normal range. CS patients, however, scored lower than expected in tests of verbal memory delayed recall and visual-perceptual function. CONCLUSIONS: Patients with CS report high levels of symptoms of impairment in all cognitive domains; however, on formal neurocognitive testing, patients scored lower than expected only in tests of verbal memory delayed recall and visual-perceptual function. These findings appear to confirm our clinical impression that cognitive impairment may be an additional feature of CS. Further studies are needed to confirm and elucidate the cause of this cognitive impairment.