Paraneoplastic Limbic Encephalitis

replaced by oat-shaped cells, appearing identical to those seen in anaplastic bronchial carcinoma’; no tumour was found in the lungs or elsewhere. Their third patient had ‘an encapsulated mass at the root of the right lung’, which consisted of fi brotic lymph nodes. Although in 1956 Charatan and Brierley [7] had previously reported patients with a ‘mental disorder associated with primary lung carcinoma’, interestingly, they concluded that it was ‘most unlikely that this fi nding (lung cancer in patient 2) is in any way related to the encephalitis but its occurrence should be noted’. They did recognize that a lung cancer had been clinically suspected in patient 3. In 1961, Verhaart [8] described 2 patients with infl ammatory lesions of the medial temporal lobe and nerve cell loss in the brainstem and cerebellum, both of whom had tumour in the mediastinal lymph nodes but no proven lung lesion. In 1962, Storring et al. [9] described an ‘undifferentiated bronchial carcinoma and an encephalitic-like picture in the limbic system’. Yahr et al. [10] reported a patient with ‘encephalopathy associated with carcinoma’ who had small-cell lung cancer (SCLC) and limbic system infl ammatory changes. In 1967, Ulrich et al. [11] described SCLC and neuronal degeneration in Ammon’s horn with some perivascular lymphocytic cuffi ng. However, it was Corsellis et al. [12] , who, in 1968, applied the term ‘limbic encephalitis’. They reported 3 additional patients and extensively reviewed the literature [12] . More reports followed and established the syndrome Paraneoplastic neurological syndromes are associated with neoplasia but are neither caused by the tumour nor by metastases in the nervous system. By defi nition, they are not caused by metabolic complications, secondary infections, nutritional disorders or toxicity of chemotherapy. Oppenheim [1] , that greatly undervalued 19th century neurologist, was probably the fi rst to associate cancer and neurological disease [2] , discussing ‘brain symptoms in carcinomatosis without demonstrable lesions in the brain’, which he shrewdly considered the result of a toxic process. Auche [3] was the fi rst to describe peripheral neuropathy in a patient with cancer. Among these syndromes [4] , clinically the most important ( table 1 ) are cerebellar degeneration, sensory neuropathy, Lambert-Eaton myasthenic syndrome, opsoclonus-myoclonus syndrome and encephalomyelitis. An original account of the sensory neuropathy complicating carcinoma was given by Denny-Brown in 1948 [5] .