RESUMO
Resumen Debido a la implementación de las colonoscopias como método de tamizaje, ha aumentado el diagnóstico de tumores neuroendocrinos rectales (TNER), la mayoría tiene un tamaño menor de 1 centímetro en el momento del diagnóstico, confinado a la submucosa y bien diferenciado; generalmente tienen un curso benigno y en su mayoría se tratan por métodos endoscópicos. Las metástasis son raras y dependen del tamaño tumoral y otros factores como la invasión a la submucosa, diseminación linfática y clasificación histológica, lo cual determinará el pronóstico y tratamiento a elección. Se presenta el caso de un tumor neuroendocrino rectal presentado en forma de pólipo durante un tamizaje endoscópico de rutina y una aproximación de la literatura actual.
Abstract Diagnosis of rectal neuroendocrine tumor (NET) has increased due to the implementation of colonoscopies as a screening method. Most rectal NETs are less than 1cm at diagnosis time, confined to the submucosa, and well differentiated. They generally have a benign course and are treated mainly using endoscopic methods. Metastases are rare and depend on tumor size and other factors such as submucosal invasion, lymphatic spread, and histologic classification, which will determine the prognosis and treatment. We present a case of a rectal neuroendocrine tumor as a polyp during routine endoscopic screening and a review of the current literature.
RESUMO
The rectal tonsil is a rare polypoid lesion exclusively found in the rectum and is considered a reactive proliferation of the lymphoid tissue. Although this lesion is benign, we recommend that it should be differentiated from carcinoid or polypoid type of mucosa-associated lymphoid tissue lymphomas, based on gross findings. In this case report, we describe a case of rectal lesions with a unique appearance in a 41-year-old man. Colonoscopy revealed two 5-mm-sized nodules located opposite from each other on the left and right sides of the lower rectum. Endoscopic mucosal resection was conducted. Histopathologically, both lesions were mainly located in the submucosa and consisted of prominent lymphoid follicles with germinal centers of various sizes. No immunoreactivity of Bcl-2 was seen in the germinal centers. Immunohistochemical staining for kappa and lambda light chains revealed a polyclonal pattern. Therefore, these lesions were diagnosed as rectal tonsils.