Asian Journal of Case Reports in Surgery

This case report discusses about a 42-year-old lady, who presented to our outpatient clinic with a right inguinal solitary swelling for a duration of 45 days. She had a prior history of a dysplastic naevus over the suprapubic region for which she underwent a wide local excision 16 months prior to this presentation. Cutaneous melanoma metastasizing to the colon has an incidence of < 1%. Stage IV melanoma has a poor prognosis. But if the metastasis is limited and resectable, it reduces the tumor burden and improves the efficacy of immunotherapy, thereby prolonging the survival. In our case, the metastasis was to the appendices epiploicae of the sigmoid colon, which was not picked up on imaging. The present case highlights the importance of considering surgical intervention in patients with atypical and limited metastatic disease. Given the rarity of metastasis to the appendices epiploicae, preoperative diagnosis is inherently challenging. Imaging modalities such as contrast-enhanced CT and PET-CT may fail to detect small peritoneal or subserosal lesions, particularly in the absence of significant metabolic activity. Consequently, many such lesions are identified incidentally during surgical exploration or histopathological examination. We are possibly presenting the first case in literature where cutaneous melanoma has spread to the appendices epiploicae.