[Sensorimotor polyneuropathy and systemic amyloidosis as paraneoplastic symptoms of a carcinoid-like well differentiated carcinoma of the breast].

History and Admission Findings: A 75-year-old woman was admitted because of weakness and paraesthesias in both legs. 15 years earlier a chest radiogram had shown numerous round foci of uncertain cause. Physical examination confirmed muscular weakness in all limbs, especially the legs, as well as abnormal superficial and deep sensory perception.
Investigations: Electromyography registered a patchy pattern of intentional muscular activity and marked denervation activity but largely normal nerve conduction. There was no evidence of inflammatory disease in the laboratory tests, including the CNS. DIAGNOSIS, COURSE AND TREATMENT: The neurological findings indicated progressive axonal sensorimotor polyneuropathy. A paraneoplastic cause was suspected, but search for a primary tumour was unsuccessful. The patient developed a urinary infection from which she died in septic shock. A carcinoid-like well-differentiated carcinoma of the breast with hematogenous metastases to liver, spleen and lung was discovered at autopsy. It also revealed severe systemic AA-type amyloidosis, involving liver, spleen heart and kidneys. In addition there was a severe progressive axonal neuropathy and marked neurogenic atrophy of the peripheral skeletal musculature. No amyloid deposition was seen.
Conclusion: In case of amyloidosis and polyneuropathy of uncertain cause a paraneoplastic pathogenesis should be considered in the differential diagnosis, even in the absence of proven malignancy.