A Rare Case Report: Anal Malignant Melanoma and Evaluation of the Literature

Abstract

Introduction: Anal malignant melanomas are relatively rare tumors. Because of their polypoid structure, they can be confused with benign anorectal diseases. Wide excision and lymph node dissection is recommended especially in melanomas including lymph node metastasis because it reduces local recurrence. Case report: We performed abdominoperineal resection + bilateral inguinal + bilateral iliac + paraaortic lymph node dissection in our 77-year-old female patient with the diagnosis of anal malignant melanoma as a result of colonoscopic biopsy performed on the polypoid mass in the anal canal. Since 2 lymph nodes located outside the pararectal fascia persisted in postoperative MRI, we performed lymph node excision with a posterior approach. And the pathology result of the excision performed in this second session was found to be compatible with metastasis. Conclusion: Lymph node dissections are beneficial in terms of local recurrence and survival, especially in patients with anal malignant melanoma with lymph node metastases.