Penile cancer is a rare but serious disease where abnormal cells grow uncontrollably in the tissues of the penis. While it accounts for less than 1% of all cancers in men in the United States, understanding the warning signs and risk factors can lead to early detection and better treatment outcomes.

How Common Is Penile Cancer?

Penile cancer is considered a rare condition in developed countries like the United States. According to medical data, the disease makes up less than 1% of all male cancers in America, with an annual incidence of about 1 in 100,000 men^[1][3]. In 2025, estimates suggest approximately 2,190 new cases will be diagnosed in the United States^[13].

The picture changes dramatically when we look at other parts of the world. Penile cancer occurs much more frequently in regions of Africa, Asia, and South America^[1][11]. These geographical differences suggest that environmental factors, cultural practices, and access to healthcare all play important roles in who develops this disease.

Age is another important factor when considering how common penile cancer is among different groups. About 80% of penile cancer diagnoses in the United States occur in men who are 55 years or older^[1][11]. This means that while the disease can affect younger men, it becomes much more likely as men get older.

What Causes Penile Cancer?

The fundamental cause of penile cancer involves healthy cells in the penis changing and beginning to grow out of control^[1]. These abnormal cells multiply and form a mass called a tumor, which is a lump of cancer cells that can damage healthy tissue around it. While researchers understand that this process happens, they still don’t fully understand what triggers these healthy cells to become cancerous in the first place.

What scientists do know is that certain changes occur in the DNA of penile cells that affect how they grow and divide^[7]. DNA acts like an instruction manual for cells, telling them when to grow, when to divide, and when to die. When this instruction manual gets damaged, cells can start behaving abnormally, growing when they shouldn’t and refusing to die when they should.

The cancer can develop anywhere on the penis, though it most commonly starts on the head of the penis, called the glans, or on the foreskin in men who haven’t been circumcised^[1][5]. The shaft, which is the main body of the penis, can also be affected, though this happens less frequently.

Risk Factors That Increase Your Chances

While risk factors don’t directly cause cancer, they increase the likelihood that someone might develop the disease. Understanding these factors can help men make informed choices about their health.

Being uncircumcised is one of the most significant risk factors for penile cancer. Circumcision is a surgical procedure that removes part or all of the foreskin from the penis^[7][10]. Many boys are circumcised shortly after birth. Men who were not circumcised at birth appear to have a higher risk of developing penile cancer later in life. Researchers believe circumcision performed in infancy or early childhood may provide protection against penile cancer, though circumcision performed as an adult doesn’t seem to offer the same benefit^[3].

Human papillomavirus, commonly called HPV, is another major risk factor. HPV is a group of viruses that can infect the genital area. High-risk strains of HPV, particularly types 16 and 18, are known to cause several types of cancers^[6]. Many of the same HPV strains that cause cervical cancer in women have been found in penile cancer cases^[1]. Research shows that HPV causes about one-third of penile cancer cases^[2].

Phimosis is a condition where the foreskin cannot be pulled back over the head of the penis^[4][7]. This condition increases cancer risk, possibly because it can trap substances and create chronic irritation. Men with phimosis may also have difficulty maintaining proper hygiene in that area.

Poor genital hygiene is another risk factor worth noting. When the area under the foreskin isn’t cleaned regularly, a substance called smegma can build up^[3]. Smegma is a combination of dead skin cells, oils, and moisture. This buildup can irritate and inflame the penile tissues over time, potentially increasing cancer risk.

Smoking and tobacco use significantly raise the risk of penile cancer^[7][10]. Tobacco contains harmful chemicals called carcinogens that can damage DNA in cells throughout the body, including those in the penis. The chemicals from tobacco can affect the penis even though they enter the body through the lungs or mouth.

Having many sexual partners throughout life is associated with increased risk^[4][7]. This connection is likely related to increased exposure to HPV and other sexually transmitted infections that can contribute to cancer development.

Warning Signs and Symptoms

Unlike some cancers that grow silently without obvious signs, penile cancer usually causes visible changes to the penis. This actually works in men’s favor because it means the cancer can potentially be detected early if men pay attention to their bodies and seek medical care promptly.

One of the most common symptoms is a painless lump or sore on the penis^[1][11]. This sore may bleed at times, but often it doesn’t cause pain, which is why some men don’t seek treatment right away. The fact that something doesn’t hurt doesn’t mean it isn’t serious.

Changes in skin color on the penis can be another warning sign. Some men notice areas that look reddish or have become irritated^[4][7]. Others might see flat growths that appear blueish-brown^[1]. The skin might become thicker in certain areas, or there might be small, crusty bumps that develop.

Unusual discharge or bleeding from the penis should always prompt a medical visit. Some men notice a foul-smelling fluid underneath the foreskin^[1][11]. This can happen when abnormal tissue breaks down or becomes infected.

Swelling and irritation, especially around the head of the penis, is another possible symptom. Medical professionals call this balanitis when it specifically involves inflammation of the glans^[1]. While balanitis can have many causes besides cancer, persistent swelling should be evaluated by a doctor.

It’s crucial to understand that many less serious conditions can cause these same symptoms. Infections, allergic reactions, and other benign conditions often produce similar signs^[1]. However, the only way to know for certain what’s causing symptoms is to have a healthcare provider examine the area and potentially perform tests.

Prevention Strategies

While no prevention method is 100% effective, several strategies can significantly reduce the risk of developing penile cancer. These approaches focus on eliminating or reducing known risk factors.

Getting vaccinated against HPV is one of the most powerful preventive measures available. HPV vaccines protect against the high-risk strains of the virus that cause cancer^[2]. Vaccination is most effective when given before someone becomes sexually active, which is why it’s recommended for preteens. However, even adults who haven’t been vaccinated can benefit from discussing vaccination with their healthcare provider.

Maintaining good genital hygiene is a simple but important prevention strategy. For uncircumcised men, this means regularly cleaning under the foreskin to prevent the buildup of smegma and reduce irritation^[3][4]. Regular washing with warm water is usually sufficient.

Circumcision, when performed in infancy or early childhood, may help prevent penile cancer^[4][7]. The procedure removes the foreskin, which eliminates the environment where smegma can collect and reduces the risk of certain infections. Some observational studies suggest that circumcision is associated with a decreased risk of penile cancer, though if this relationship is truly causal, researchers estimate that about 909 circumcisions would be needed to prevent a single case of invasive penile cancer^[13].

Quitting smoking and avoiding all tobacco products is essential for cancer prevention. Tobacco use is linked to many types of cancer, including penile cancer^[7][10]. The benefits of quitting smoking extend far beyond just reducing cancer risk—it improves blood circulation, enhances immune function, and reduces inflammation throughout the body.

Practicing safer sex behaviors can reduce exposure to HPV and other infections. This includes using condoms during sexual activity and limiting the number of sexual partners^[4]. While condoms don’t provide complete protection against HPV, they do reduce transmission risk.

Regular self-examination and awareness of what’s normal for your body allows for early detection of any changes. Men should periodically check their penis for any new lumps, sores, color changes, or other abnormalities. Catching problems early, before symptoms become severe or the cancer spreads, dramatically improves treatment outcomes.

How Penile Cancer Affects the Body

Understanding how penile cancer changes normal body functions helps explain why certain symptoms occur and why treatment approaches work the way they do. The pathophysiology of penile cancer—the physical and biochemical changes the disease causes—provides insight into the disease process.

The penis is made up of several different types of tissue. The shaft contains three columns of spongy tissue filled with blood vessels^[4][7]. Two of these columns, called the corpora cavernosa, make up most of the penis. The third column, called the corpus spongiosum, surrounds the urethra, which is the tube that carries urine and semen out of the body. All of this erectile tissue is wrapped in connective tissue and covered with skin.

In about 95% of penile cancer cases, the disease starts as squamous cell carcinoma^[1][2]. This type of cancer begins in the squamous cells, which are the flat, thin cells that make up the outer layer of skin on the penis. When these cells become cancerous, they start multiplying rapidly and don’t die when they should.

As the cancer grows, it can invade deeper layers of tissue in the penis. It may penetrate through the skin into the spongy erectile tissue beneath, and eventually it can reach the blood vessels and lymphatic channels that run through the penis. This is significant because once cancer cells reach these vessels, they can travel to other parts of the body.

Penile cancer most often spreads first to lymph nodes in the groin area^[3][13]. Lymph nodes are small structures that are part of the immune system and help filter harmful substances from the body. When cancer cells travel through lymphatic vessels to these nodes, they can start growing there, forming new tumors. From the groin lymph nodes, the cancer can spread to lymph nodes in the pelvis and eventually to distant organs.

Less common types of penile cancer behave somewhat differently. Melanoma of the penis, which starts in the cells that produce skin pigment, tends to be more aggressive and can spread more quickly^[1]. Basal cell carcinoma, which begins in the bottom layer of the skin, typically grows more slowly. Adenocarcinoma starts in glandular cells, while sarcomas develop from muscle or connective tissue and are extremely rare.

Before invasive cancer develops, there’s often a precancerous stage. Doctors now use the term penile intraepithelial neoplasia (PeIN) to describe these precancerous changes in penile skin cells^[5][6]. At this stage, the abnormal cells haven’t yet invaded deeper tissues, but they have the potential to become cancer if left untreated. Detecting and treating cancer at this early stage can prevent it from progressing.

The location where cancer develops can affect symptoms and treatment options. Cancer on the foreskin may be noticed earlier simply because the foreskin moves and any changes are more visible during normal hygiene^[5]. Cancer on the glans or shaft might be detected at different stages depending on how carefully someone examines their body.

As penile cancer progresses, it can affect normal bodily functions in several ways. If the tumor grows large enough, it might interfere with urination, though this typically doesn’t happen in early stages^[6]. The cancer itself usually doesn’t cause erectile dysfunction in its initial stages, though the psychological impact of having cancer and concerns about treatment can certainly affect sexual function.

The body’s immune response to the cancer can cause inflammation in the affected area. This inflammation contributes to symptoms like swelling, redness, and irritation. Sometimes the tumor tissue breaks down or becomes infected, which is what causes the foul-smelling discharge that some men notice.

Understanding these physical and biochemical changes helps explain why certain symptoms develop and why doctors use specific approaches to diagnose and treat the disease. It also underscores why catching the cancer before it invades deeply or spreads to lymph nodes makes such a dramatic difference in treatment success and long-term outcomes.