SMTs of somatic soft tissue that lack atypia, necrosis, and mitotic activity can with reasonable confidence be labeled leiomyomas
The presence of any mitoses in SMTs of subcutaneous or deep soft tissue should be regarded as indicative of potential malignancy; WLE and careful F/U advised
M, male; F, female; HPF, high power fields; IHC, immunohistochemistry; ER, estrogen receptor protein; PR, progesterone receptor protein; SMTs, smooth muscle tumors; WLE, wide local excision; F/U, follow-up. The authors concluded that a smooth muscle tumor of somatic soft tissue with 1–5 mitoses/50 HPF should be regarded as “leiomyoma of uncertain malignant potential.”