June 18, 2013 - Question 3
1) A 21-year-old male with no significant past medical history presents with fatigue, shortness of breath, weight loss, and leg pain. He had previously been diagnosed with “growing pains,” six months ago, but the pain has failed to remit since that time. Plain radiographs of the chest as well as a subsequent CT scan of the chest are abnormal. A lung biopsy is performed and is seen in the image below. Alkaline phosphatase, vimentin, variable smooth muscle actin and desmin are positive; EMA and keratin are negative. Which of the following histologic characteristics are typical for this diagnosis?
a. Osteoid composed of fine, lacelike pink matrix
b. Spaces separated by septa composed of highly malignant cells
c. Purely spindle cell growth with only a small foci of matrix
d. Malignant-appearing cartilage with hyperchromasia and hypercellularity with spindling at the periphery of cartilage lobules
e. Predominance of benign giant cells
Check answer here.
Source: BoardVitals, 6/18/2013