FDG PET of alveolar soft part sarcoma

Alveolar soft part sarcoma of the orbit: A case report

Alveolar soft part sarcoma is a rare soft tissue neoplasm that accounts for approximately 1% of all sarcomas and is usually identified in the extremities in adults. The occurrence of alveolar soft part sarcoma in the orbit is extremely rare, estimated at approximately 5% – 15% among all cases of alveolar soft part sarcoma . Here, we present a case of 29-year-old woman with orbital alveolar soft part sarcoma. We describe the magnetic resonance and F-18 2-fluoro-2-deoxy-D-glucose-position emission tomography/computed tomography findings of this case. This young woman had a spindle-shaped mass. A higher signal compared to the extraocular muscle on T1-weighted images, numerous flow voids on T2-weighted images, and intense enhancement could be key findings of this disease.

CT, MRI, and FDG PET/CT in a patient with alveolar soft part sarcoma

Alveolar soft part sarcoma (ASPS) is a rare malignant soft tissue tumor. We present a case, who had a history of a left pulmonary ASPS resection 5 years ago, with a tumor in the left lower extremity showing high vascularity mimicking hemangioma on enhanced CT and MRI. This tumor showed intense FDG uptake on FDG PET/CT with SUVmax of 6.8, indicating a malignant soft tissue tumor. Complete resection of the tumor was performed. A diagnosis of ASPS was confirmed by pathology. This case highlights FDG PET/CT is helpful for differentiating ASPS from hemangioma according the degree of FDG uptake.

Alveolar soft part sarcoma arising from the kidney: imaging and clinical features

Alveolar soft part sarcoma (ASPS) is an extremely rare malignant soft tissue sarcoma primarily affecting young patients. It usually occurs in the lower extremities, although it can occur in soft tissue anywhere in the body. However, to our knowledge, there has been no case of primary ASPS originating from the kidney in the literature. We herein present the imaging and clinical features of an ASPS which occurred in a 16-year-old male presented as a palpable mass in the left side of the abdomen.

Imaging features of primary and metastatic alveolar soft part sarcoma: single institute experience in 25 patients

OBJECTIVE

To describe imaging features of primary and metastatic alveolar soft part sarcoma (ASPS).

METHODS

In this institutional review board-approved and Health Insurance Portability and Accountability Act-compliant retrospective study, 25 patients (14 males; mean age, 25 years; range, 18-40 years) with pathologically proven ASPS seen at our institute between 1995 and 2013 were included. Imaging of primary tumours in 5 patients and follow-up imaging in 25 patients were reviewed by 2 radiologists in consensus. Clinical information was obtained from electronic medical records.

RESULTS

The most common sites for the primary tumour were extremities (17/25, 68%) and torso (6/25, 24%). Primary tumours (n = 5) were well circumscribed, compared with skeletal muscle, were isodense on CT, hyperintense on T1 and T2 weighted images with intense post-contrast enhancement, prominent feeders on CT and flow voids on MRI. Metastases developed in 23/25 (92%) patients, 18 at presentation. The most common sites of metastases were the lungs (100%), lymph nodes (74%), bones (57%) and brain (43%). Visceral and nodal metastases were hypervascular. At the time of reporting the results, 15 patients have died, 6 are alive and 4 were lost to follow-up. Median survival was 74 months for those without brain metastases (n = 8) and 60 months for those with brain metastases (n = 7). Median survival was shorter for patients with metastases at presentation.

CONCLUSION

ASPS most commonly involves the lower extremities of young adults, is hypervascular on imaging, often metastasizes at presentation, frequently to lung, nodes, bones and brain, and has an indolent course despite metastases. Brain metastases and high tumour burden (number of metastatic sites) at presentation decreased survival in our study.

ADVANCES IN KNOWLEDGE

ASPS has an unusual pattern of metastases to the brain and nodes in addition to lung and bones. It has an indolent course despite metastases.