A rare case of recurrent malignant triton tumor in a male with NF1: Case report and mini-review

BACKGROUND: Malignant triton tumors (MTT) represent a rare subset of tumors with rhabdomyoblastic differentiation within the heterogeneous group of malignant peripheral nerve sheath tumors (MPNST). CASE PRESENTATION: Here, we report on a case of a 25 year-old male with a history of neurofibromatosis type I and MTT of the mediastinal wall who presented in our clinic with a pelvic tumor and multiple hypervascular mesenteric masses and underwent resection. Upon resection, histological findings revealed an MTT of the omentum and an atypical neurofibroma of the pelvis with focal transitions to a low-grade MPNST. The patient relapsed just one month later and died 3 months after the surgery. CONCLUSION: Clinically, MTTs are characterized as highly aggressive tumors that are fast-growing and prone to local recurrence and distant metastasis. To date, there is no treatment consensus available yet and many patients succumb to the disease shortly after diagnosis. This is because the pathogenesis of MTT remains unknown and patients with MTT are often diagnosed at a late stage of disease. Our case presents valuable teaching points in terms of providing a possible progression model based on the coexistence of a low-grade MPNST and MTT in the context of NF1 and an atypical neurofibroma in this patient. Close monitoring of patients with NF1 and atypical neurofibromas or MPNST might therefore help to diagnose MTT at an earlier stage.