It is generally accepted that Lambert-Eaton myasthenic syndrome (LEMS) is associated with cancer in 50% to 60% of cases, the overwhelming majority of these cancers being small cell carcinomas of the lung. O’Neill et al 1stated that in cases in which the cancer is not small cell carcinoma of the lung the association may be fortuitous. However, small cell carcinomas can sometimes arise in other organ systems. They are considered, like small cell carcinomas of the lung, to be of neuroendocrine origin and presumably have the same antigenic potential. Posner2 states that occasional cases of LEMS can be seen in association with non-pulmonary small cell carcinoma, particularly of the prostate and cervix, although reference to these occurrences in the literature is scant. We present a case of LEMS clearly causally related to extrapulmonary small cell carcinoma.

A 70 year old housewife presented in April 1996 with a three month …