Nabil AM Salmo *
Azad Kareem Saeedb**
Snur Muhammad-Amin Hassan***
and Hasanaein H Khudeir****
* Department of Pathology and Forensic Pathology, School of Medicine, Sulaimani University.
**Department of Histopathology, College of Veterinary Medicine, Sulaimani University.
MAST CELLS AND APOPTOTIC BODIES IN SEBORRHEIC KERATOSIS: A COMPARATIVE STUDY BETWEEN UVB INDUCED SEBORRHEIC KERATOSIS IN MICE AND SPORADIC CASES IN HUMANS
Exposure to ultraviolet type B (UVB) radiation induces a number of pathologic changes in skin, including
erythema, edema, epidermal hyperplasia, sunburn cell formation, immune suppression and eventually leads
to cancer development.
To elucidate the differences in histological appearances of mast cells and apoptotic bodies between the two
species (mice and human) among hyperkeratotic and acanthotic types of seborrheic keratosis (SK).
Materials and methods
Thirty paraffin blocks were used in this study; fifteen histologically confirmed acanthotic and hyperkeratotic
SK cases in human (9 acanthotic and 6 hyperkeratotic) and fifteen blocks from both types acanthotic and
hyperkeratotic SK cases in mice induced by UVB light (9 acanthotic and 6 hyperkeratotic).
Our results revealed that there was a significant correlation between mast cells and apoptotic bodies for both
groups according to Pearson Correlation test. In human cases mast cells counting ranged between 2-10 with a
mean number of 5.2/1HPF, while the total number of apoptotic bodies ranged from 1-4 with a mean number of
2.6/10HPF. When compared to mice cases, the number of mast cells were increased with a range of 12-23 and
with a mean number of 19.067/1HPF, while apoptotic bodies were decreased with a range of 3-20/10HPF and
with a mean number of 9.4/10HPF.
Dermal mast cells infiltration were remarkably increased in mice skin specimens which were exposed to
UVB. The number of apoptotic bodies in UVB induced cases were more than in human sporadic cases.
Keyword: UVB, seborrheic keratosis, apoptotic bodies, mast cells.