RECURRENCE OF MALIGNANT PERIPHERAL NERVE SHEATH TUMOR

Peripheral nerve sheath tumor (PNST) is known as a benign tumor called Schwannomas, developed from the Schwann cells that produce myelin and collagen, and can occur in a wide variety of locations. In some cases, it can take a malignant turn and grow as a pelvic mass known as malignant peripheral nerve sheath tumor (MPNST), malignant schwannoma, malignant neurofibroma, malignant mesenchynoma and neurogenic sarcoma. Our case report presents a female patient presenting dysuria and pelvic pain. The clinical examination revealed a palpable mass in the lower abdomen. The computer tomography (CT) scan of the abdomen and pelvic region showed a tumor mass that was in contact with the nearby organs, but not infiltrating them. After the surgery, histopathology confirmed the MPNST proliferation. A month after, the patient returned for a follow-up and presenting pelvic pain. The CT scan of the abdomen and pelvic region showed a tumoral mass compressing the nearby organs, but not infiltrating them. The patient was referred to oncology board for palliative treatment. The particularity of this case report is the short period of time recurrence of the MPNST, rather than metastases. The most important treatment for MPNSTs remains surgery, trying to achieve negative margins. However, there have been reported two cases of unresectable MPSNT with partial remission to chemo- and radiotherapy.