Contributed by Ibrahim Batal, MD and Teresa McHale, MD
Published on line in January 2006
A 79-year-old male is status post distal pancreatectomy for low-grade multilocular intraductal papillary mucinous tumor (Image 1), and post splenectomy for incidental B cell chronic lymphocytic leukemia (Image 2) in 2002.
A follow-up abdominal CT scan in 2005 showed 2.9 x 2.5 cm lesion in the head of the pancreas. Serum CA19-9 was 2.9 U/ml.
The patient underwent endoscopic ultrasound guided FNA which revealed a hypoechoic and heterogenous area 2.0 x 1.5 cm. The cytology slide was read as "suspicious for low-grade mucinous neoplasm". A Whipple procedure was performed.
A tan, hemorrhagic, well circumscribed, and rubbery mass measuring 2.3 x 2.0 x 1.6 cm was identified. The mass involved the head of the pancreas. It was 0.1 cm from the post-surgical pancreatic margin. (Images 3 and 4)
Microscopic examination revealed a nodular lesion surrounded in some areas by a pseudo-capsule (Image 5). The nodule consisted of spindle cells in a background of an edematous stroma containing blood vessels, with extravasated red blood cells, few lymphocytes, histiocytes, and monocytes. The spindle cells had a fascicular pattern of growth with minimal degree of atypia and no mitoses (Images 6, 7 and 8).
Giant cell reactions to suture material (Image 9), and tangle masses of nerve fibers surrounded by fibrous tissue (Image 10) were presented at the periphery of the lesion. Also, few papillary mucinous lesions were identified in the remaining of the pancreas; the epithelial cells were pseudostratified with elongated nuclei (Image 11). CD34 (Image 12) and c-kit (Image 13) immunostains were performed on the nodular lesion, and were negative. Smooth muscle actin (SMA) was focally positive (Image 14).