Neoplasias de origen sebáceo asociadas a Síndrome de Muir-Torre. A propósito de un caso / Sebaceous neoplasias associated to Muir-Torre syndrome. A propos of a case

El Síndrome de Muir-Torre (SMT) descrito desde 1967, es una genodermatosis con herencia autosómica dominante y penetrancia variable, caracterizada por la presencia de neoplasias cutáneas de origen sebáceo manifestado en áreas seborreicas, como la cara y cuero cabelludo. Los adenomas son los tumores sebáceos más frecuentes. Se han descrito también hiperplasias, neoformaciones sebáceas quísticas, epiteliomas o carcinoma. Los mismos pueden presentarse de manera aislada o múltiple; en conjunto con al menos una neoplasia visceral maligna. Entre las descritas con frecuencia están las gastrointestinales. Se pueden asociar a otras neoplasias, como las renales, las de endometrio, útero y de laringe. El diagnóstico clínico está dado por la presencia y asociación de un tumor visceral primario y otro de origen sebáceo. El tratamiento de esta entidad se basa en la exéresis de los tumores y el seguimiento especializado según el sistema afectado. Se presentó el caso de un hombre de 62 años de edad, cuya afección cutánea demostró múltiples lesiones de origen sebáceo de siete años de evolución por lo que se le realizaron complementarios para identificar entidades asociadas (AU).

The Muir-Torre syndrome, described since 1967, is a genodermatosis with dominant autosomal inheritance and variable penetrance, characterized by the presence of sebaceous skin neoplasias manifested in seborrheic areas as the face and scalp. Adenomas are the most frequent sebaceous tumors. Hyperplasia, cystic sebaceous neoformations, epitheliomas or carcinomas have been also described. They could appear in an isolated or multiple way, in all with at least one malignant visceral neoplasia. The gastrointestinal ones are among those frequently described. They might be associated to other neoplasias, as the renal ones, or the ones of the endometrium, the uterus and the larynx. The clinical diagnosis is given by the presence and association of one primary visceral tumor and another of sebaceous origin. The treatment of this entity is based on the tumors resection and the specialized follow-up according to the affected system. The case of a man, aged 62 years, is presented; his cutaneous condition showed multiple sebaceous lesions of seven years of evolution. Complementary exams were carried out for identifying associated lesions (AU).

The role of immunohistochemistry in the Muir-Torre Syndrome

Muir-Torre Syndrome is defined by the coexistence of sebaceous skin tumors and internal malignancies. Mutations in the DNA mismatch repair genes are found in the inherited form of the disease, resulting in the absence of crucial enzymes involved with DNA replication process. This case describes a patient with sebaceous adenoma and colorectal carcinoma, meeting the criteria for Muir-Torre Syndrome. The immunohistochemical analysis of the skin lesion was an important tool to confirm the diagnosis, as it revealed nuclear negativity for MSH2 and MSH6.

Muir-Torre Syndrome: case report and molecular characterization / Sindrome de Muir-Torre: relato de caso e caracterizacao molecular

CONTEXT: Muir-Torre syndrome is a rare autosomal dominant genodermatosis caused by mutations in the mismatch repair genes. It is characterized by the presence of sebaceous skin tumors and internal malignancies, affecting mainly the colon, rectum and urogenital tract. Awareness of this syndrome among physicians can lead to early diagnosis of these malignancies and a better prognosis. CASE REPORT: We report the case of a Chilean patient who, over the course of several years, had multiple skin lesions, endometrial cancer and colon cancer. The syndrome was diagnosed using molecular techniques such as microsatellite instability analysis, immunohistochemistry and DNA sequencing, which allowed us to find the causative mutation. CONCLUSION: Molecular diagnostics is a highly useful tool, since it allows clinicians to confirm the presence of mutations causing Muir-Torre syndrome. It is complementary to the analysis of the clinical data, such as dermatological presentation, presence of visceral malignancies and family history of colorectal tumors, and it provides important knowledge to help physicians and patients choose between treatment options. .

CONTEXTO: A síndrome de Muir-Torre é uma genodermatose autossômica dominante rara causada por mutações nos genes de reparo de incorreções. Caracteriza-se pela presença de tumores sebáceos da pele e doenças malignas internas, afetando principalmente cólon, reto e trato urogenital. A consciência desta síndrome pelos médicos pode levar ao diagnóstico precoce dessas doenças malignas e a um melhor prognóstico. RELATO DE CASO: Relatamos o caso de uma paciente chilena que, ao longo de vários anos, teve lesões cutâneas múltiplas, câncer de endométrio e câncer de cólon. A síndrome foi diagnosticada com técnicas moleculares, como a análise de instabilidade de microssatélites, imunoistoquímica e sequenciamento de DNA, o que nos permitiu encontrar a mutação causadora. CONCLUSÃO: Diagnóstico molecular é uma ferramenta muito útil, uma vez que permite que os clínicos confirmem a presença de mutações causadoras de síndrome de Muir-Torre. É complementar para a análise dos dados clínicos, tais como a apresentação dermatológica, a presença de doenças malignas viscerais e história familiar de tumores colorrectais, e fornece conhecimentos importantes para ajudar os médicos e os pacientes a escolher entre opções de tratamento. .