Pain, weakness, and incontinence in a patient with sacral malignant peripheral nerve sheath tumor and neurofibromatosis type 1.
Patient is a 33-year-old male who presented as a transfer with concern for cauda equina syndrome. He experienced worsening lower extremity weakness over the past year with increase in pain over the past 2-3 months with recent bowel and bladder incontinence. MRI revealed a mass measuring 14 x 10 x 11 cm with severe sacral destruction. He was not a surgical candidate due to size of mass. He participation in therapy sessions was limited due to severity of pain.
Oncology recommended a biopsy which was positive for high-grade sarcoma with abundant necrosis, consistent with malignant peripheral nerve sheath tumor (MPNST). He underwent an inpatient chemotherapy regimen of four cycles of etoposide and ifosfamide. Pain control included methadone, PCA hydromorphone, pregabalin, and tizanidine.
Follow up imaging showed interval increase of the mass with dimensions 14 x 15 x 14 cm and subsequent mass effect on the colon, ureters, and bladder.
MPNST is a rare malignancy most commonly seen in patients with neurofibromatosis type 1, often arising from a plexiform neurofibroma. Surgical removal is the first line treatment however was not considered in this patient due to the extensive size and invasion of adjacent structures including sacral spinal nerves and pelvic soft tissue. 5-year survival rate of MPNST in a patient with neurofibromatosis type 1 is as low as 10%.
Presented is a rare case of giant sacral MPNST that produced profound lower extremity weakness, bowel/bladder incontinence, and intractable pain.
This patient elected to be discharged to SNF near his parent’s home with subcutaneous hydromorphone PCA pump with hospice care.