The dog was presented with a rapidly growing skin 2 nodules located near the left tarsal joint. The owner reported a bite wound at the same site approximately one year earlier, which had healed completely following routine wound care.
Recently, a small raised masses appeared at the same location and enlarged over two weeks. The lesions was non-painful and non-pruritic, but the dog occasionally licked the area. No systemic illness was noted.

• n examination, a firm, dome-shaped, alopecic nodules measuring about 3 cm in diameter each was observed on the medial aspect of the left tarsal region.
  The surface was smooth with no local heat, discharge, or pain.
  Palpation of regional lymph nodes revealed no enlargement or tenderness.

• Fine-Needle Aspiration (FNA): Showed a uniform population of round cells with moderate pale cytoplasm and round nuclei, typical of Langerhans cell origin.
• Cytological Diagnosis: Consistent with histiocytoma.
• No evidence of infection or malignant transformation was identified.

Due to the location near the joint, where friction and trauma could delay regression or cause ulceration, surgical excision
The mass was completely excised with clean margins, and Sample submitted to lab

Microscopic evaluation confirmed a proliferation of Langerhans-type round cells in the dermis, forming a dense cellular mass.
The cells exhibited abundant pale cytoplasm, round nuclei, and minimal atypia.
No invasion into surrounding tissues was observed.
Findings were consistent with Atypical (Deep )histiocytoma.