A 46-year-old Arabic man presented with a penile pain and erectile dysfunction for 6 months. Eight months previously, he had undergone abdomino-perineal resection for a moderately differentiated adenocarcinoma of the rectum. Before surgery, neo-adjuvant radio-chemotherapy had been prescribed for him. The pathological examination of his resected specimen disclosed a ypT3N0 tumor (American Joint Committee on Cancer (AJCC) 2009), with negative margins and a very poor therapeutic response (around 5%). There was no tumor instability, as tumor cells were positive for MLH1 (mutL homolog 1), MSH2 (mutS homolog 2), MSH6 (mutS homolog 6) and PMS2 (PostMeiotic segregation increased 2) at immunohistochemical evaluation. At multidisciplinary meeting (MDM), an adjuvant chemotherapy has been decided for the patient, with six cycles of XELOX regimen (capecitabine plus oxaliplatin). Eight months later, before the end of the adjuvant chemotherapy, he presented with a painful induration located at the right-lateral side of the penile root. The magnetic resonance imaging (MRI) showed tumoral infiltration of the right corpora cavernosa, penile bulb and neighboring perineal soft tissues. A biopsy of the corpora cavernosa was performed and the histological examination on hematoxylin-eosin-saffron (HES) stained sections, showed tumoral glands invading the penile structures. Tumor cells had eosinophilic cytoplasm with oval nuclei and irregular contours. At immunohistochemistry, tumor cells were positive for CK20 (cytokeratin 20) and CDX2 (caudal type homeobox transcription factor 2), negative for CK7 (cytokeratin 7) and PSA (prostatic specific antigen). The diagnosis of penile metastasis from rectal adenocarcinoma has been disclosed. At present, the patient is still under his adjuvant chemotherapy (XELOX regimen).