Pleural Spindle Cell Neoplasm in a Patient With Neurofibromatosis Type I

Abstract

A twenty-two year old male with NF1 presented with multiple pleural masses, consistent with spindle cell neoplasm. Given his history, malignant peripheral nerve sheath tumor is suspected and a rare presentation of this disease. CASE PRESENTATION: A twenty-two-year-old male with Neurofibromatosis Type 1 (NF1) presented to the Emergency Department with abdominal pain. Past medical history included malignant peripheral nerve sheath tumor (MPNST) of the left leg. Despite resection, there was local recurrence within one month and the patient subsequently received chemotherapy with ifosphamide and etoposide, radiation, and surgical resection with a below-knee amputation. A one-cm right lower lobe pulmonary nodule with mild FDG avidity was found on surveillance PET scan. An attempted biopsy was unsuccessful due to the location of the nodule. Unfortunately, the patient was lost to followup. He presented six months later with abdominal pain and dyspnea and was found to have a large right pleural effusion with pleural masses causing mediastinal shift (Figure 1). Tube thoracostomy was performed. Pleural fluid analysis showed a lymphocyte-predominant, exudative effusion. Infectious workup, including bacterial and fungal cultures and adenosine deaminase level, was negative. Cytology demonstrated only reactive mesothelial cells. Pleuroscopy was performed, and multiple pleural-based masses (Figure 2) were biopsied and found to be consistent with spindle cell neoplasm. Immunostaining was negative for neurofilament, CD34, STAT6, Bcl-2, SMA and desmin, CD117, Dog-1, Sox-10, ALK-1, beta-catenin. There was rare staining of S100 and WT-1 positivity, with further histopathological workup pending.