Askin's Tumor in an Adult: Case Report and Findings on 18F-FDG PET/CT

Abstract

Primitive neuroectodermal tumor (PNET) of the chest wall or Askin's tumor is a rare neoplasm of chest wall. It most often affects children and adolescents and is a very rare tumor in adults. In this case report, we present an Askin's tumor occurred in a 73-year-old male. The patient was admitted with a history of 3-month lower back pain and cough. In computed tomography, there was a lesion with dimensions of 70 x 40 x 65 mm in the superior segment of the lower lobe of the left lung. Positron emission tomography/computed tomography with 18F-flourodeoxyglucose revealed a pleural-based tumor in the left lung with a maximum standardized uptake value of 4.36. No distant or lymph node metastases were present. The patient had gone through surgery, and wedge resection of the superior segment of left lobe and partial resection of the ipsilateral ribs were performed. Pathology report with immunocytochemistry was consistent with PNET and the patient received chemotherapy after that.

Figure 1

Axial (a) and sagittal (b) CT images demonstrate a lesion in the upper lobe of the left lung invading pleura and adjacent ribs (arrows).

Figure 2

Axial-fused PET/CT image shows a pleural-based tumor with a calculated SUVmax of 4.36 (arrow).

Figure 3

Small-sized round cells with scanty cytoplasm were seen in light microscopic evaluation (×40).

Figure 4

Immunohistochemistry revealed positivity with (a) CD 99, (b) vimentine, and (c) synaptophysin (×400).