Abstract:

PORPOSE: Langerhans cells and mast cells are bone marrow derived cells. They represent a critical role in the immune system in the epidermis and dermis. In the present study, we aimed to evaluate the role of mast cells and Langerhans cells in benign and malignant squamous tumors. MATERIALS and METHODS: This study included 12 patients with seborrheic keratosis, 9 patients with actinic keratosis, 15 patients with keratoacanthoma and 33 patients with squamous cell carcinoma. Dermal mast cells and epidermal peri and intratumoral Langerhans cells were labeled with mast cell tryptase and CD1a antibodies respectively. RESULTS: The number of mast cells were significantly increased in the patients with squamous cell carcinoma in comparison with seborrheic keratosis (p=0.001). However, this parameter did not show significant difference between patients of other groups. The number of intratumoral Langerhans cells in seborrheic keratosis were significantly increased in comparison with squamous cell carcinoma (p=0.026). The peritumoral Langerhans cells were increased in squamous cell carcinoma (p=0.007, p=0.001) and keratoacanthoma (p=0.001, p=0.001) in comparison with actinic keratosis and seborrheic keratosis. CONCLUSION: Our immunohistochemical study has demonstrated that peritumoral Langerhans cells and mast cells are increased in number in keratoacanthoma and squamous cell carcinoma. Both epidermal Langerhans cells and dermal mast cells which have some contributions in the immune system, are different in number in benign and malignant skin tumors.

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