ABSTRACT
Objective: Immunohistochemistry with p16 antibody is used as a diagnostic marker in
several gynecologic pathologies. The purpose of the present study was to
evaluate the diagnostic and prognostic significance of p16 immunohistochemistry
in various uterine smooth muscle tumors. Methods:
Tissue specimens, including 29 leiomyomas, 13 smooth muscle tumors of uncertain
malignant potential (STUMP), and 17 leiomyosarcomas, were obtained from 59
patients with uterine smooth muscle tumors. The prevalence of p16 expression in
various uterine smooth muscle tumors was examined using immunohistochemistry
methods and we investigated the association between p16 expression and various
clinicopathologic parameters, including prognosis of leiomyosarcomas. Results: The prevalence of p16
expression of leiomyomas, STUMP, and leiomyosarcomas tumors was 10.3%, 38.4%,
and 76.4%, respectively. The prevalence and immunohistochemistry scores of p16
were significantly higher in the leiomyosarcomas group than in the leiomyomas or
STUMP tumor groups. In the leiomyosarcomas groups, p16 immunohistochemistry
scores were significantly higher in the groups with more advanced stage, higher
mitotic activity, and recurrence. The relationship among p16
immunohistochemistry scores and age, tumor size, extent of necrosis, and degree
of myometrial invasion was not significant. High expression of p16 in
leiomyosarcomas was linked to shorter disease-free and overall survival. Conclusions: The use of p16
immunohisitochemistry is a useful marker in differential diagnosis in various
uterine smooth muscle tumors. Moreover, p16 overexpression possibly plays an
important role in tumor progression and we demonstrate that p16 may be a
predictor of overall survival in patients with leiomyosarcoma tumors.