Why does penile cancer cause new lump or swelling?

Penile cancer may begin as a persistent change on the skin, foreskin, glans, or shaft. Abnormal cells can form a firm area, ulcer, wart-like growth, or thickened patch. Local inflammation may make the tissue red, tender, or swollen. Swelling can also occur when lymphatic drainage is affected, including in nearby groin nodes. A new lump has many non-cancer causes, such as infection, irritation, cysts, scar tissue, or benign skin growths. Its appearance cannot establish the diagnosis, and a clinician may need to examine it and sometimes test a tissue sample.

Arrange a medical appointment for a lump or swelling that persists, enlarges, bleeds, breaks down, changes colour, or is associated with discharge, pain, or difficulty retracting the foreskin. Do not squeeze, cut, or repeatedly rub the area. Note when it appeared, whether it changes, and any urinary or sexual symptoms. A clinician can inspect the penis and groin, check for infection or skin disease, and decide whether further testing is needed.

Seek urgent help for inability to pass urine, rapidly increasing swelling, severe pain, heavy bleeding, fever with spreading redness, or a trapped foreskin that cannot return to its normal position. These problems can damage tissue or signal an infection requiring prompt treatment.

Ask what the lump may represent, whether infection or irritation could explain it, how quickly it should be assessed, whether a biopsy is needed, and which changes should prompt urgent care.