Tehran University of Medical Sciences Case Reports in Clinical Practice 2538-2683 6 1 2021 05 15 33 36 EN Ghazaleh Shaker Department of Pathology, Imam Khomeini Hospital Complex, Tehran University of Medical Sciences, Tehran, Iran. Forough Alborzi Department of Gastroenterology and Hepatology, Imam Khomeini Hospital Complex, Tehran University of Medical Sciences, Tehran, Iran. Masoomeh Safaei Department of Pathology, Imam Khomeini Hospital Complex, Tehran University of Medical Sciences, Tehran, Iran. Samira Moiini Department of Pathology, Imam Khomeini Hospital Complex, Tehran University of Medical Sciences, Tehran, Iran. 2020 06 06 2020 07 03 Duodenal melanoma constitutes a very small number of gastrointestinal malignant melanomas. The small intestine is a common site for the metastatic spread of cutaneous melanomas; however, its metastatic involvement from a primary rectal melanoma origin has seldom been reported. We present the histopathologic features of an unusual case of primary rectal melanoma metastasizing to the duodenum. https://crcp.tums.ac.ir/index.php/crcp/article/view/361 https://crcp.tums.ac.ir/index.php/crcp/article/download/361/395