Combined Mohs Micrographic Surgery in a Collision Tumor

Area of Science:

• Dermatology
• Surgical Oncology
• Pathology

Background:

• Collision tumors, where two distinct malignancies coexist in the same site, present unique diagnostic and therapeutic challenges.
• Basal cell carcinoma (BCC) and melanoma are common skin cancers, but their simultaneous occurrence as a collision tumor is infrequent.
• The management of such complex cases requires precise surgical techniques to ensure complete eradication and minimize recurrence.

Observation:

• A 73-year-old male presented with a collision tumor in the right ear, comprising both basal cell carcinoma and melanoma in situ.
• The patient underwent Mohs micrographic surgery, a specialized technique for removing skin cancer.
• The surgery involved a combination of paraffin-embedded and frozen tissue sections for accurate margin assessment.

Findings:

• Multiple surgical stages were necessary to achieve clear, tumor-free margins, indicating the complexity of the tumor.
• The surgical defect was successfully reconstructed by the plastic surgery team, preserving the anatomical structure of the ear.
• The combined use of paraffin-embedded and frozen sections proved effective in managing this specific collision tumor.

Implications:

• The successful application of Mohs micrographic surgery highlights its efficacy in treating complex skin cancer presentations.
• Combining paraffin-embedded and frozen section techniques offers a valuable approach for diagnosing and treating collision tumors of the skin.
• This case underscores the importance of tailored surgical strategies for preserving function and form in oncologic reconstruction.