Dermatosis paraneoplásicas / Cutaneous paraneoplastic syndromes

Los síntomas paraneoplásicos son patologías marcadoras de procesos malignos internos que afectan órganos y sistemas diferentes del comprometido por el proceso neoplásico. Entre los sistemas y órganos que con mayor frecuencia expresan estas alteraciones se encuentran el sistema nervioso y la piel. La asociación entre neoplasias y dermatosis había sido reconocida desde el siglo III a C. En 1986 Mc Lean estableció los criterios necesarios para definir una dermatosis como paraneoplásica: aparición simultánea o próxima entre la dermatosis y el tumor y que ambos debían tener una evolución paralela. A estas consideraciones debemos agregar como criterios de inclusión, que deben presentar características clínicas e histológicas diferentes entre ambos procesos, que exista alta frecuencia de asociación entre ambas patologías y uniformidad entre el tipo de carcinoma y la expresión cutánea, la cual a su vez debe ser de infrecuente presentación. Aunque la etiopatogenia certera de estos procesos no puede ser demostrada en forma fehaciente, si pueden esbozarse algunas hipótesis que nos permiten agrupar las diferentes manifestaciones cutáneas en cuatro grandes grupos con características etiopatogénicas comunes como la producción o consumo de sustancias biológicamentes activas (enzimas, hormonas, vitaminas), sobre producción y expresión de citocinas, producción de auto-anticuerpos y reducción de la capacidad de defensa del huésped.

Paranoplastic syndromes of malignant diseases that affect internal organs and systems different from the compromised organs by the neoplastic process. The systems and organs that most frequently express these complications are the nervous system and the skin. The association between tumors and skin diseases has been recognized since third century b.C. In 1986 Mc Lean defined the main criteria for a paraneoplastic dermatosis as: co-occurrence or proximity between the dermatosis and the tumor and a parallel evolution. As inclusion criteria to these considerations we must add that a different clinical and histological features of both processes must be present, a high frequency of association between the two conditions and uniformity in the type of skin carcinoma and the skin expression, which must be an unusual presentation. Although accurate pathogenesis of these processes can't be demonstrated some hypotheses can be stated to allow us to combine the various cuateneous manifestations in four groups with common etiopathogenic characteristics such as production or consumption of biologically active substances (enzymes, hormones, vitamins), production and expression of cytokines, production of auto-antibodies and reduced capacity of host defense.

Clinical analysis of 12 Korean Lambert-Eaton myasthenic syndrome (LEMS) patients

The Lambert-Eaton myasthenic syndrome (LEMS) heralds the occurrence of malignancy, especially small-cell lung cancer (SCLC), but it can also occur in the absence of cancer. Twelve patients were diagnosed as LEMS by clinical features and the classical electrophysiological triad, which includes a low amplitude of compound muscle action potentials (CMAP), decremental responses on low-rate stimulation, and incremental responses on high-rate stimulation on the repetitive nerve stimulation (RNS) test. There were 6 male and 6 female patients, ranging in age from 49 to 66 years. Malignancy(all were SCLC) was found in 7 patients. Males predominantly expressed the paraneoplastic form; whereas the primary autoimmune form was found only in women, who showed a good response to corticosteroid treatment. The neurological features were similar in both groups: proximal lower limb weakness, depressed muscle stretch reflexes, and dryness of mouth in nearly all patients. Bulbar dysfunction and limb paresthesia were a little more frequent in the paraneoplastic form. In RNS tests, the characteristic electrophysiological abnormalities were found in all patients and were more profound in the paraneoplastic form. We concluded that LEMS is commonly associated with malignancy, especially SCLC, but it should also be stressed that there are many female LEMS patients who do not harbor any malignancy at all, and that other treatment strategies such as immunotherapy should be considered for these patients.

Carcinoma de pequenas células de pulmäo / Small-cell lung carcinoma

O câncer de pulmäo é uma das maiores causas de mortalidade por câncer em todo o mundo. Apesar dos progressos no diagnóstico e tratamento, a sobrevida em cinco anos permanece menor que 10 por cento. O carcinoma de pequenas células de pulmäo (CPCP) totaliza aproximadamente 20 por cento de todos os casos de câncer do pulmäo e difere dos outros tipos histológicos pelo seu comportamento biológico e resposta terapêutica. Até a década de 60, a sobrevida dos pacientes com CPCP era de três meses. Com a combinaçäo de quimioterapia e radioterapia a sobrevida mediana varia de um a dois anos. O comportamento desse tipo de tumor reflete-se no grande número de síndromes paraneoplásicas que freqüentemente o acompanham, e que parecem estar relacionadas intimamente com suas células de origem. Sua propensäo para a disseminaçäo precoce torna o estadiamento da extensäo da doença parte fundamental da avaliaçäo clínica. O CPCP é sensível tanto à químio quanto à radioterapia. Existem na literatura mundial múltiplos esquemas de tratamento usando essas modalidades isoladamente ou associadas. O objetivo deste artigo é descrever sucintamente os aspectos gerais do CPCP no que ele se diferencia dos demais, assim como uma revisäo nos seus aspectos clínicos e no tratamento.