Insidious malignant triton tumor of the chest wall with late flare-up.

Malignant triton tumor is a rare malignant peripheral nerve sheath tumor with rhabdomyoblastic differentiation. Most of these tumors are located in the head, neck, and extremities, and about half of cases are associated with neurofibromatosis type 1 featuring cafe-au-lait spots or cutaneous neurofibromas. We present a 76-year-old man with an insidious chest wall tumor with late progressive painful enlargement and pleural and pulmonary involvement. Complete resection of the affected thoracic wall as well as single separate lesions in the parietal pleura and left upper lung was carried out. The pathological examination confirmed that it was a malignant triton tumor. The patient received adjuvant chemo-radiotherapy but eventually succumbed to disease relapse and distant metastases 6 months after the surgery.