Malignant peripheral nerve sheath tumor (Triton tumor) located in mesentery. Case report

Background: Triton malignant tumor is a variant of malignant peripheral nerve sheath tumors with rhabdomyosarcomatous differentiation, It's most frequent location is in head, neck, limbs and trunck. The diagnosis is based on morphological com position and inmunohistochemical studies.Clinical case: Male 44 years old, electively scheduled for resection of a mesen teric cyst and abdominal wall plasty for incisional hernia, with adequate postoperative course and discharged at the third day. The pathology report shown a malignant peripheral nerve sheath tumor with rhabdomyoblastic differentiation (Triton tumor) with positive inmunohistochemistry for S-100 protein, actin muscle specific, CD34, desmin, myogenin, Ki-67, and CK18. Discussion: Malignant Triton tumor is about 5% of all MPNST and presents rhabdomyoblastic differentiation; the diagnosis is histopathological and inmunohistochemical, positive for S-100 protein, desmin, vimentin, myogenin, actin, and myosin. Complete resection of the tumor is the most effective therapeutic approach, with RO resections if possible, as the role of adyuvant therapy with chemotherapy and radiotherapy is not well defined and has not been proven to be effective. Conclusions: Triton tumor is associated with a high incidence of local recurrence or distant metastases as well an aggres sive behavior and poor prognosis.