|
February 2019
Contributors:
Karen E. Trevino MD
PGY3-Department of Pathology and Labortoey Medicine Residency
Indiana University School of Medicine
and
Ahmed K. Alomari, FEL, MD
Assistant Professor of Clinical Pathology & Laboratory Medicine
Indiana University School of Medicine
Clinical history: A 56-year-old male presented to his primary care physician with a slowly enlarging subcutaneous nodule on his upper arm. No changes to his overlying skin were seen and an excisional biopsy was performed.
Microscopic examination: The biopsy demonstrates a subcutaneous mass (Figure 1) consisting of sheets and cords of spindled to round cells in a fibrous, hyalinized stroma (Figures 2 and 3). The mass is well encapsulated with a partial rim of bone and fibrous capsule surrounding it (Figure 4). No significant atypia or mitotic activity is seen in either the spindled cells or the bone.
For PC users, right click to open image in a new window, then zoom to enlarge.
Fig. 1
Figure 1. Subcutaneous mass
Fig 2.
Figure 2. Rounded cells in hyalinized background (10x)
Fig.3
Figure 3. Rounded and spindled cells (20x)
Fig 4.
Figure 4. Bony capsule (2x)