Schwannoma retroperitoneal maligno / Malign retroperitoneal schwannoma

Los tumores del retroperitoneo son poco frecuentes y se clasifican según el tejido del que se originan. Se presenta el caso de una paciente con dolor en el hipocondrio derecho y tumor en esta zona, pérdida de peso y molestia dolorosa en la cara anterolateral del muslo derecho. En el examen físico se halló palidez cutáneo-mucosa y tumoración indolora en el hipocondrio y flanco derecho. El ultrasonido abdominal mostró una masa homogénea de 14,11 cm y la tomografía computarizada de abdomen permitió observar un tumor retroperitoneal derecho que rechazaba el riñón. El urograma excretor mostró rechazamiento anteromedial del riñón derecho. Se extirpó un tumor encapsulado con pocas adherencias peritumorales. Mediante estudio histológico se confirmó un tumor de células fusiformes con hipercromatismo y pleomorfismo nuclear, numerosas mitosis y áreas de necrosis y el diagnóstico de tumor maligno de la vaina de un nervio periférico(AU)

The retroperitoneal tumors are infrequent and are classified according to the original tissue. This is a case presentation of a patient presenting with pain in right hypochondrium and a tumor in this zone, weight loss and painful discomfort in the anterolateral face of right thigh. In physical examination we found cutaneous-mucous paleness and painless tumor in hypochondrium and right flank. Abdominal ultrasound (US) showed a homogenous mass of 14,11 cm and abdominal computed tomography allows to see a right retroperitoneal tumor rejecting the kidney. Excretory urogram showed a anteromedial rejection of right kidney. An encapsulated tumor with a few peritumoral adherences was removed. By histological study it was possible to confirm a fusiform cells tumor with hyperchromatism and nuclear pleomorphism, numerous mitosis and areas of necrosis and in the diagnosis of malign tumor of the sheath of a peripheral nerve(AU)

[Mandibular malignant triton tumor: a case report]

Malignant peripheral nerve sheath tumors [MPNSTs] are very rare. Malignant triton tumor is an aggressive variety of MPNSTs with rhabdomyoblastic differentiation. In this study we reported the clinical, radiographic, histopathologic and immunohistochemical features of an intramandibular malignant triton tumor. The patient was a 31 year-old male who was referred to maxillofacial surgery ward of Mashhad dental school with a painful swelling in the anterior part of mandible and facial asymmetry. After histopathological evaluation, surgery was performed and immunohistochemical staining confirmed the diagnosis of Triton tumor. Patient was referred for further necessary treatments. In cases of mandibular tumors with initial histopathologic findings of sarcoma, uncommon differential diagnosis such as peripheral nerve sheath tumors must be considered as well