METHODS::Malignant thymoma can be invasive and may require radical resection. Here we present a case with phrenic nerve, right upper lobe, bilateral brachiocephalic vein, and superior vena cava involvement. Total venous reconstruction was performed with a cryopreserved aortic allograft by using the aortic root, ongoing transverse arch, and innominate arterial branch. The patient then had postoperative radiotherapy for a total of 63 Gy over 35 treatment days. Follow-up imaging demonstrated no evidence of recurrence and intermediate-term patency but with homograft calcification developing at 4 years.

METHODS:OBJECTIVE:To examine the CT and MRI characteristics of extraneural perineuriomas. MATERIALS AND METHODS:With IRB approval, our institutional imaging database was retrospectively reviewed for cases of pathologically proven extraneural perineuriomas. CT and MRI features were recorded, correlative imaging analyzed, and the electronic medical record cross-referenced. RESULTS:We identified ten patients [(seven males, three females, mean age 49.4 ± 18.3 years (range, 16-70 years)]. All cases were pathologically confirmed. Nine cases were conventional soft tissue extraneural perineuriomas, including one with "reticular" features and one with histologic features of malignancy; the tenth case contained admixed Schwann cells (hybrid perineurioma/schwannoma). Six out of ten patients underwent CT and ten of ten MRI evaluation. Nine out of ten MRIs were performed with IV contrast. Five lesions were subcutaneous, four intermuscular, and one intramuscular. Mean lesion diameter was 4.3 ± 2.7 cm (range, 0.9-10.2 cm). Nine out of ten lesions were well circumscribed; one had irregular margins. On CT, five of six were hypodense and one isodense compared to skeletal muscle. Most lesions were T1 isointense (5/10) or hypointense (4/10) and T2 hyperintense (7/10) relative to skeletal muscle, and demonstrated solid enhancement (6/9). There was no evidence of muscular denervation on any MRI exam, and a nerve of origin was identified in two out of ten cases. CONCLUSIONS:Extraneural perineuriomas have a distinctly different imaging appearance from intraneural perineuriomas, manifesting as rounded or ovoid soft tissue masses, without evidence of muscular denervation, and usually without an apparent nerve of origin. Because these features mimic other benign and malignant soft tissue lesions, including sarcomas, biopsy or excision is needed for definitive diagnosis.

METHODS::We present the case of a 46-year-old woman with a presumed diagnosis of multiple unprovoked pulmonary emboli. Her cardiorespiratory function continued to deteriorate despite optimal medical therapy. At surgical thrombectomy she was identified to have an intimal soft tissue lesion arising from the right pulmonary artery. This lesion was subsequently diagnosed as a pulmonary artery sarcoma, a rare neoplasm that carries a poor prognosis. It typically presents at an advanced stage with pulmonary vascular obstruction. Surgical debulking is the mainstay of therapy to restore ventilation perfusion mismatching and relieve right-sided heart strain. Median survival of these patients is 20 months with adjuvant chemoradiotherapy. At 9 months after surgery, she has undergone 6 cycles of chemotherapy and has stable disease with no metastases.