#2: Corpus uteri
Source 1: WHO Class Female Reproductive Organs
pgs: 122, 138
Notes: 4th edition
Reportability--Corpus uteri: Is smooth muscle tumor with uncertain malignant potential (STUMP) reportable? See Discussion.
Spindled cell lesion of smooth muscle origin (desmin and SMA are positive, CD34, S100, pancytokeratin, Pax8, MDM2 and CDK4 are negative). Many of the cells have hyperchromatic, bizarre-shaped nuclei. Mitotic activity is inconspicuous. There are no areas of necrosis. The overall findings in this biopsy is best classified as a "STUMP"; however, a leiomyosarcoma cannot be excluded.
STUMP (smooth muscle tumor of uncertain malignant potential) is not reportable. According to the WHO classification of uterine corpus tumors, the behavior code for STUMP is /1.