We present the case of a 70-year-old man with a history of gastrectomy for gastric adenocarcinoma 12 years ago and Gleason VII prostate carcinoma (2 cylinders of 6 affected by the tumour), treated surgically by radical prostatectomy ten years ago, with a lymph node affected by the tumour and androgen blockage to date, with a PSA of 0.06 at the last check-up. He came to the Emergency Department of our hospital with a non-painful exophytic lesion on the glans penis of about five weeks' duration. He did not remember having had any previous injury or trauma in the area, and reported some episodes of bleeding with friction since the appearance of the lesion.

Examination of the patient revealed a round, dark reddish exophytic lesion on the dorsum of the glans penis, approximately two centimetres in diameter, with a tendency to bleed, elastic and non-painful consistency. No lymphadenectomy was palpable and the rest of the physical examination of the patient was normal
A biopsy of the lesion was performed and during the operation it was observed that it was a tumour with a macroscopic, non-infiltrating appearance, located in the mucosa of the glans penis, with areas of a thrombosed appearance and easily friable.

The intraoperative anatomopathological analysis was reported as a lesion composed of undifferentiated cells with nuclear hyperchromatism, pleomorphism and a large number of mitoses and blackish pigment, which would be compatible with the diagnosis of melanoma.
The resection was completed with a subtotal penectomy with a four-centimetre safety margin from the edge of the lesion and a bilateral superficial inguinal lymphadenectomy with nodes unaffected by the tumour. A thoracoabdominal CT scan was performed, which showed no metastatic disease. Pathological examination of the penectomy specimen showed a maximum depth of invasion of 1.5 mm. Immunohistochemical analysis with S-100 and HMB 45 confirmed the diagnosis of melanoma (1).

