Paraneoplastic neurological syndromes associated with gastric cancer: a case report and review of the literature

Paraneoplastic neurological syndromes (PNS) are associated with small-cell lung cancer, breast and gynecological cancers. We describe a gastric neoplasm presented with neurological symptoms. A 74-year-old male presented with tonic–clonic seizures. Initial investigations were normal; however, brain magnetic resonance imaging showed abnormal signal intensity in the hippocampi. A diagnosis of PNS was suspected. The patient was then diagnosed with a gastric neuroendocrine carcinoma with N-type voltage-gated calcium channel antibodies. The neurological impairments improved after the primary was resected and the patient remains free of cancer and paraneoplastic syndrome. We reviewed 10 cases of PNS associated with gastric cancer and found several characteristics: (1) older men, (2) neuroendocrine component or predominance, (3) oncological outcome for patients with PNS is better than for patients without PNS, and (4) neurological impairment is diagnosed 6 months prior to the diagnosis of gastric malignancy. In conclusion, elderly men with symptoms suggestive of PNS should be investigated for a gastric neuroendocrine malignancy.