When it comes to men's health, penile cancer might not be the first thing that comes to mind. But even though it's pretty rare, especially in the United States and Europe where it accounts for less than 1% of all cancers in men, it's still something all men should be aware of. Getting diagnosed with any kind of cancer is scary, but the good news is that penile cancer is treatable, especially if it's caught early.

Understanding Penile Cancer

The Cellular Origins of Penile Cancer

So what exactly is penile cancer? It's when healthy cells in the penis start growing out of control and form a tumor. Penile cancer most commonly begins in the skin cells of the penis, with the majority of cases (about 95%) being squamous cell carcinomas. These cancers originate in the flat, thin squamous cells that line the surface of the penis. Other less common types of penile cancer can start at a deeper point in the skin (basal cell carcinoma), from connective tissue, smooth muscle and/or blood vessels (sarcoma), from the glands (adenocarcinoma), or even melanocytes, the cells responsible for the skin's pigment (melanoma). Identifying the origin of a patient's cancer helps doctors determine the most effective treatment approach.

Prevalence of Penile Cancer in the United States and Worldwide

Now one might wonder - how common is this? Well, in the U.S., only about 1 in 100,000 men get penile cancer each year. However, the global incidence of penile cancer varies substantially, with higher rates observed in parts of Asia, Africa, and South America. These geographical variations can be attributed to differences in risk factors such as HPV (Human Papillomavirus) infection rates and smoking prevalence, among other factors. Despite these variations, the overall global prevalence remains low.

Penile Cancer Causes and Risk Factors

One of the most notable risk factors for penile cancer is infection with the Human Papillomavirus (HPV).

In the realm of men's health concerns, penile cancer stands out due to its potential impact on health and quality of life. Scientists don't know why healthy cells become cancer cells and form tumors. They have, however, identified factors that appear to increase a person's risk:

HPV Infection and Penile Cancer: A Significant Link

One of the most notable risk factors for penile cancer is infection with the Human Papillomavirus (HPV). High-risk strains of HPV, particularly HPV 16 and 18, are known to cause several types of cancers, including penile cancer. The virus can increase the risk of penile cells becoming cancerous by altering their DNA.

Vaccination against HPV emerges as a powerful preventive measure, significantly reducing the risk of penile cancer associated with the virus. Early vaccination is recommended and can provide a safeguard against the development of all HPV-related cancers.

Uncircumcised Men and Increased Penile Cancer Risk

Not being circumcised might increase a man's chances of getting penile cancer. Circumcision is a procedure that removes all or part of the foreskin, and it's usually done when a boy is just a baby. Some experts think that getting circumcised as an infant can help prevent penile cancer later in life.

Researchers aren't completely sure why circumcised men have a lower risk of penile cancer, but it might have something to do with other risk factors. For example, men who are circumcised can't get a condition called phimosis, and they also don't build up a substance called smegma under their foreskin (see more below).

Phimosis, Poor Hygiene, and Their Associations

Phimosis is when the foreskin of the penis cannot be fully retracted, which can create an environment that leads to penile cancer if hygiene is poor. These conditions can lead to the accumulation of smegma. This substance can irritate and inflame the penile tissues, increasing cancer risk. Addressing phimosis through medical treatment and maintaining good genital hygiene can help reduce this risk.

The Role of Tobacco Use in Increasing Risk

Smoking or other tobacco use is another well-established risk factor for penile cancer. Research shows that smokers are three to four and a half times more likely to develop this cancer compared to non-smokers. This link remains strong even when accounting for other factors like sexual history. All tobacco products (such as cigarettes, snuff, or chewing tobacco) contribute to a higher risk of developing the disease due to the harmful substances in tobacco that can damage the DNA of cells in the penis. Stopping tobacco use can decrease this risk, so men looking to improve their overall health and reduce their cancer risk might benefit from a tobacco cessation program.

Age

Penile cancer is more common in men over 50 years of age. However, penile cancer can affect men at any age.

PUVA treatment for psoriasis

Psoralen and ultraviolet A photochemotherapy (PUVA) is a type of radiation treatment for psoriasis. Researchers have found that men who undergo this treatment are at higher risk for penile cancer.

Lichen sclerosus

Lichen sclerosus is a skin condition that affects the genitals. It can raise a man’s risk for both HPV infection and penile cancer.

HIV and AIDS

Men with AIDS have a weakened immune system, which can raise their risk for both HPV infection and penile cancer.

Penile Cancer Signs & Symptoms

So what should a man look out for? The early detection of penile cancer can significantly influence outcomes and prognosis. Awareness of these warning signs can lead to early medical intervention.

Some of the more common symptoms include the following:

Alterations in Penile Skin

Initial signs often manifest as noticeable changes in the skin covering the penis, particularly on the glans, foreskin (for those who are uncircumcised), or even the shaft. These alterations might include:

• Thicker areas of skin
• Discoloration or new color variations
• The emergence of lumps or sores, which may or may not bleed
• The appearance of a reddish, velvety rash, particularly under the foreskin
• The development of small, crusty bumps or flat, bluish-brown patches
• Unusual discharge or bleeding, emitting a foul odor from under the foreskin

Sores or lumps associated with penile cancer are not always painful. However, any new growth or change that persists or worsens over a period of about four weeks warrants medical attention.

Swelling

Another sign can be swelling at the penis's end, particularly when it causes difficulty or inability to retract the foreskin. This symptom requires prompt evaluation by a healthcare professional.

Lymph Node Changes

Penile cancer can spread to lymph nodes in the groin area, leading to swelling. While swollen lymph nodes can result from various causes, including infections, their enlargement due to penile cancer would feel like smooth lumps under the skin.

The Importance of Paying Attention to Symptoms

If a man notices any of these symptoms, he shouldn't feel embarrassed - he should go see a doctor right away. Doctors have seen it all before and are there to help. The sooner penile cancer is found, the easier it is to treat. And it's important to keep in mind, these signs don't always mean it's cancer. They can also be caused by other conditions, like infections. But it's always better to get checked out just in case.

Diagnosing Penile Cancer

Understanding the process of diagnosing penile cancer can help demystify the various steps involved.

Step 1: Initial Consultation and Physical Exam

The steps involved in diagnosis often begin with a consultation and a comprehensive physical examination. During this initial visit, your healthcare provider will discuss your medical history and any symptoms you've been experiencing and conduct a thorough physical exam. Particular attention is paid to the penis, where the doctor will look for any signs of abnormal growths, lumps, or changes in the skin's appearance. This non-invasive examination identifies potential concerns that warrant further investigation.

Step 2: Biopsy – The Cornerstone of Diagnosis

The next step is a biopsy if any suspicious areas are found during the physical exam. A biopsy involves removing a small sample of tissue from the affected area, which is then examined under a microscope by a pathologist. Biopsy is the most reliable method for diagnosing penile cancer, as it allows direct observation of cancer cells. Doctors may use several types of biopsies depending on the size and appearance of the lesion. Incisional biopsies remove part of the affected area and are often used for larger or ulcerated lesions. Excisional biopsies, where the entire lesion is removed, are typically done for smaller nodules or plaques. Lymph node biopsies might also be performed to check for cancer spread, using fine needle aspiration or surgical removal for deeper nodes or when the cancer has possibly spread to lymph nodes. For all the above procedures, healthcare providers administer either local anesthesia or general anesthesia – depending on the biopsy type–to minimize discomfort.

Step 3: Imaging Tests – Understanding the Extent

After a biopsy confirms penile cancer, imaging tests like C.T. (Computed Tomography) scans, MRI (Magnetic Resonance Imaging), and ultrasound might be used; these tests help determine the cancer's extent, showing how far it has spread within the penis, to lymph nodes, or to other parts of the body. C.T. scans provide detailed cross-sectional images, MRIs offer detailed images of soft tissues, and ultrasounds use sound waves to visualize internal structures. Each imaging test has a specific role in staging the cancer and planning treatment.

Step 4: Pathology Reports and Further Evaluation

Following the biopsy and imaging tests, a pathology report will detail the type of cancer, its aggressiveness (grade), and its extent (stage). This report will guide the treatment plan. In some cases, additional tests or consultations with other medical specialists might be recommended to ensure a comprehensive approach to care. The findings in the pathology report enable healthcare professionals to recommend the most effective treatment options tailored to the individual's specific condition.

Staging and Prognosis of Penile Cancer

Staging is a process that occurs after a diagnosis of penile cancer has been confirmed. It involves determining the extent of the cancer, including its size, depth of invasion, and whether it has spread to nearby lymph nodes or distant parts of the body. The staging process is important for determining the treatment plan, as it allows clinicians to customize the approach to the patient's specific needs.
Penile cancer is typically staged using the TNM system, which considers:

T (Tumor): The size and depth of the primary tumor.
N (Nodes): Whether the cancer has spread to nearby lymph nodes.
M (Metastasis): Whether the cancer has spread to other parts of the body.

Based on the TNM classifications, penile cancer is then assigned a stage, from 0 (the least advanced) to IV (the most advanced). Lower-stage cancers are generally confined to the penis. In contrast, higher-stage cancers may have spread to lymph nodes or distant organs.

Prognosis of Penile Cancer

The prognosis of penile cancer depends on several factors, including the cancer's stage at diagnosis, the type of cells involved, and the patient's overall health. One of the most encouraging aspects of penile cancer treatment is the high success rate in early-stage diagnoses. When detected and treated early, the chances of a complete recovery and minimal impact on quality of life are significantly increased.
Factors that can affect the prognosis of penile cancer include:

Early Detection

Early-stage cancers (I and II) have a higher success rate of treatment, often with options that preserve the function and appearance of the penis.

Lymph Node Involvement

Cancer in the lymph nodes can affect the treatment choice and prognosis. Early lymph node detection and treatment are key to improving outcomes.

Type of Cancer Cells

Certain types of penile cancer may be more aggressive and require more intensive treatment.

Penile Cancer Treatment Options

Treatment options for penile cancer largely depend on the extent of the cancer and how far it has spread. Some men undergo a combination of treatments. Therapies may destroy cancer cells, stop their growth, or both.

Surgical Options: Tailored Approaches for Best Outcomes

Surgery is often the primary treatment for penile cancer, and the specific surgical procedure selected depends on the cancer's stage and location. The goal is always to remove the cancer while preserving as much normal function and appearance as possible.

Limited Excision (including circumcision): Cancer cells are cut out directly. Surrounding skin may also be removed. If the wound is small, it may be closed with stitches. More extensive wounds may be closed with a skin graft.

Mohs Micrographic Surgery: A precise technique where cancerous tissue is removed layer by layer, examining each layer under a microscope until no cancer cells are detected. It's beneficial for small, early-stage tumors and aims to preserve penile tissue.

Laser Ablation: This treatment utilizes a high-intensity light to destroy cancer cells. It is suitable for small surface tumors and offers the benefit of minimal tissue damage.

Total glans resurfacing: TGS involves the removal of the skin and lamina propria layers of the glans penis (the tip of the penis), reaching down to the corpus spongiosum, and is followed by the application of a skin graft.

Glansectomy: If the cancer cells are confined to the glans, they might be surgically removed. Surgeons may be able to build a new glans with skin grafts.

Partial Penectomy: This surgery involves removing part of the penis, but enough of the penis is preserved to allow the patient to urinate standing up. It's considered for larger tumors.

Total Penectomy: The removal of the entire penis, used for very large tumors or when the cancer is in the body of the penis. Urination is still possible through a new opening created in the perineum.

It might be possible to reconstruct the penis in a procedure called phalloplasty. Surgeons use tissue from other parts of the body and might add a penile implant to allow for erections. These surgeries are done after the penectomy once it is certain that the cancer cells are gone.

In cases where the cancer is very advanced, sometimes the scrotum and testicles are removed as well. Without the testicles, the man’s body will no longer produce adequate amounts of the hormone testosterone. However, hormone replacement therapy may be an option.

Lymph node surgery: Treating penile cancer that has spread to the lymph nodes near the groin and pelvis follows an established, step-by-step protocol. Penile cancer usually spreads from one area to another in a known pattern before it reaches more distant parts of the body. How much the cancer has spread to the lymph nodes greatly affects a person's prognosis. Doctors use different tests like ultrasounds and biopsies to examine the nodes. They then decide on the best treatment by looking at things like the primary tumor stage and tumor grade and if it has spread to the lymph channels or nerves. Men with a higher risk of their cancer spreading get more intense treatments focused on the lymph nodes. Newer surgery methods that are less harsh are now also used, especially for those whose cancer hasn't spread as extensively. What the tests show about the cancer will decide if the person needs to be watched closely or needs more treatment, like surgery or other therapies.

Non-surgical treatments

Non-surgical treatments for penile cancer may include:

Topical therapy: Topical means that medicine is applied directly to the skin of the penis.

One type is topical chemotherapy, in which a chemotherapy drug is applied as a cream to the penis. This type of chemotherapy differs from systemic chemotherapy, in which drugs flow through the bloodstream.

Another type of topical therapy uses the drug imiquimod, which helps the person’s own immune system attack cancer cells.

Topical therapies may cause skin irritation. However, other topical medicines may be prescribed to relieve this symptom.

Radiation Therapy: Radiation therapy employs high-energy rays to destroy cancer cells or slow their growth. It is often used when surgery isn't an option or to remove remaining cancer cells post-surgery. There are two methods:

• External radiation. Radiation is delivered from outside the body using a special machine.
• Internal radiation (brachytherapy). Radiation is contained in pellets or delivered through needles, wires, or catheters. It is then placed in or near the cancer itself.

Chemotherapy: Systemic chemotherapy plays a critical role in treating advanced penile cancer, especially when the disease has spread beyond the penis. With this treatment, men are given chemotherapy drugs by mouth or through an injection. The drugs then travel throughout the body.

Patients usually have chemotherapy in cycles that last a few weeks. They have treatments, a rest period, then treatments, then another rest period, and so on.

Chemotherapy can shrink tumors, relieve symptoms, and improve survival rates.

The treatment of penile cancer has seen significant advancements, with a focus on preserving quality of life while effectively combating the disease. Each treatment plan is tailored to the individual, considering not just the cancer's characteristics but the patient's preferences and overall health.

Penile Cancer Treatment Side Effects

Addressing the side effects of penile cancer treatment is crucial for patients to navigate their recovery path with dignity and strength. Healthcare teams understand the complexities involved in treating penile cancer, not just from a medical standpoint but also considering the profound emotional and physical impacts it can have on patients.

Physical Side Effects of Penile Cancer Treatment

The treatment of penile cancer, depending on the modality used, can lead to a variety of physical side effects. It's important to recognize these potential effects to prepare and manage them effectively:

Surgical Treatments Side Effects: Post-operative pain, changes in penile appearance or function, and challenges with urination can occur. For more extensive surgeries, adjustments to body image and sexual function are significant concerns. In some cases, rehabilitation and reconstructive surgeries can offer pathways to recovery and adaptation.

Radiation Therapy Side Effects: Patients may experience skin irritation in the treated area, fatigue, and potentially long-term changes in penile tissue that could affect sexual function. Skin care protocols and energy conservation strategies become key components of care.

Chemotherapy Side Effects: Common side effects include nausea, fatigue, hair loss, and increased infection susceptibility. Medications and supportive therapies can help mitigate these effects, maintaining the patient's quality of life.

Emotional Impacts

Beyond the physical side effects, the emotional and psychological impact of penile cancer and its treatment is profound.

Beyond the physical side effects, the emotional and psychological impact of penile cancer and its treatment is profound. Feelings of anxiety, depression, and concerns about body image are common. The emotional journey can be as challenging as the physical one, necessitating support from mental health professionals, support groups, and open discussions with healthcare providers about any concerns.

The Role of Communication in Side Effect Management

Open and honest communication with the healthcare team helps manage side effects effectively. No concern is too small, and no question is trivial. By discussing potential and experienced side effects:

Personalized Management Strategies can be developed and tailored to each individual's specific needs, lifestyle, and treatment plan.

Supportive Care options, ranging from physical rehabilitation services to mental health support, can be explored.

Adjustments to Treatment Plans may be possible, optimizing efficacy while minimizing discomfort.

While the side effects of penile cancer treatment can be challenging, there is a multitude of strategies and resources available to manage them so that patients can lead fulfilling lives post-treatment. Penile cancer treatment is a collaborative effort, with a dedicated team of healthcare professionals working to not only treat the cancer but also to support patients through the side effects of treatment.

Coping and Support for Penile Cancer Patients

A patient's advancement through penile cancer diagnosis, treatment, and beyond is undeniably challenging, touching not just the physical aspects of one's being but the emotional and psychological as well. Patients should embrace support and understand the role of mental health in the healing process.

The Power of Professional Counseling

Professional counseling offers a safe space to express fears, concerns, and emotions that accompany a penile cancer diagnosis and subsequent treatment. Counselors specialized in helping patients undergoing cancer treatment can provide coping strategies, emotional support, and therapeutic interventions to manage anxiety, depression, and stress related to treatment and its side effects. Seeking professional counseling is a proactive step toward maintaining mental well-being.

Finding Strength in Support Groups

Support groups present a unique avenue for connection and understanding among those with similar experiences. These groups offer an environment of empathy, shared stories, and mutual encouragement. Whether in-person or online, support groups enable patients to exchange practical advice on managing side effects, discuss emotional challenges, and celebrate milestones in recovery. The shared experiences within these groups can significantly diminish feelings of isolation, reinforcing that one is part of a community that understands and supports each other.

The Importance of Mental Health in Healing

Attending to one's mental health is a crucial part of the healing process. It influences one's outlook on treatment, promotes resilience in the face of challenges, and improves overall quality of life. Patients are encouraged to communicate openly with their healthcare providers about their emotional well-being, explore mental health support options, and actively seek resources that cater to their psychological needs.

Penile Cancer and Sexuality

Sexuality is understandably a significant concern for men with penile cancer. Most men find that they can still enjoy intimacy.

Radiation therapy and chemotherapy may affect erections temporarily. However, these issues usually get better after treatment.

Sexual function after surgery depends on the extent of the surgery. Men who undergo excision, glansectomy, or partial penectomy may still enjoy penetrative intercourse. Individuals who have undergone total penectomy may need to explore alternative methods of intimacy. Some men are able to have their penis reconstructed.

Penile Cancer Prevention and Screening

So can penile cancer be prevented? While there's no guaranteed way to stop it from developing, there are definitely steps a man can take to lower his risk:

The Shield of HPV Vaccination

The Human Papillomavirus (HPV) is linked to a variety of cancers, including penile cancer. Vaccination against HPV is a powerful tool in preventing cancer. The HPV vaccine is recommended for boys and girls. It is ideally administered before they become sexually active to maximize its protective effects against the high-risk strains of the virus known to cause cancer. For men, receiving the HPV vaccine can significantly reduce the risk of penile cancer by preventing the initial viral infection that can lead to cellular changes in the penis. Embracing HPV vaccination is a forward step in cancer prevention, safeguarding not only individual health but also contributing to the overall reduction of HPV-related cancers in the population.

Circumcision in Infancy

Some experts believe that circumcising baby boys might help protect them from getting penile cancer when they grow up. Studies have shown that men who were circumcised as babies have a lower chance of getting penile cancer later in life compared to men who weren't circumcised. However, getting circumcised as an adult doesn't seem to lower the risk as much.

Penile cancer is extremely rare in the United States, even among uncircumcised men. The American Academy of Pediatrics says that the health benefits of circumcising baby boys are greater than the risks, but they also say that these benefits aren't significant enough to advise circumcision for all newborn boys. In the end, the decision to circumcise is a personal one that often depends more on social and religious factors than on medical evidence.

The Role of Good Hygiene

Maintaining good genital hygiene is another way to reduce the risk of penile cancer. Regular washing of the penis and the foreskin for uncircumcised men helps to prevent the build-up of smegma. This substance can cause irritation and inflammation of the penile tissues, potentially increasing the risk of cancer. Good hygiene practices are simple yet effective measures that men can incorporate into their daily routines that offer a layer of protection against the development of penile cancer.

Stopping the Use of Tobacco Products to Lower Penile Cancer Risk

Stopping the use of tobacco products is a preventative strategy against numerous health conditions, including penile cancer. Using tobacco, whether by smoking or chewing, significantly raises the risk of developing penile cancer. Quitting smoking has immediate and long-term benefits for cancer prevention. Within hours of stopping, the body begins to repair the damage caused by smoking. Long-term, the risks of cancer continue to decrease. For penile cancer, the carcinogenic effects of tobacco can be significantly mitigated by cessation, potentially reducing the risk of developing this type of cancer.

The Importance of Regular Check-Ups for Early Detection

Regular medical check-ups can help detect penile cancer early. During these visits, healthcare providers can look for any signs of abnormalities or changes that could indicate the presence of cancer or precancerous conditions. Men are encouraged to perform self-examinations and promptly report any concerns, such as lumps, sores that do not heal, or changes in the color or texture of the skin. Early detection of penile cancer significantly enhances treatment outcomes and survival rates.

Other Prevention Strategies

• Having safe sex. Using condoms and dental dams can lower transmission of HPV and HIV, the virus that causes AIDS.
• Covering the genitals during PUVA treatment. Men who have PUVA treatment for psoriasis should make sure their genitals are covered to avoid radiation exposure.

Penile Cancer Research

The quest for advanced treatments and diagnostic tools for penile cancer is unfolding. Recent research efforts have focused on targeted therapies, immunotherapy, and enhanced diagnostic technologies.

Targeted Therapies: Aiming with Precision

One of the most promising areas of penile cancer research involves targeted therapies. These treatments are designed to identify and attack specific cancer cell markers while sparing healthy tissue, offering a more personalized approach to cancer care. Ongoing research is focused on understanding the genetic and molecular landscapes of penile cancer to identify targets for these therapies. Scientists are working to unravel the complexities of the disease at a molecular level with the hope of developing new drugs that can more precisely target cancerous cells without the broader side effects of conventional chemotherapy.

Immunotherapy: Harnessing the Body's Defense

Immunotherapy is a cancer treatment that leverages the body's immune system to fight cancer. This area of research holds particular promise for penile cancer, where treatments such as checkpoint inhibitors can potentially enhance the immune system's ability to detect and destroy cancer cells. Scientists are exploring various immunotherapy agents, aiming to identify those that are most effective in treating penile cancer. The prospect of immunotherapy offers hope for improved survival rates and a better quality of life for patients.

Advancing Diagnostic Tools: The Key to Early Detection

Early detection is critical in the battle against penile cancer since it significantly impacts treatment outcomes and survival rates. Researchers are dedicating efforts to develop and refine diagnostic tools to detect penile cancer at its earliest stages. Innovations in imaging technologies and molecular diagnostics, including biomarkers in blood or tissue samples, are areas of investigation. By improving our ability to identify penile cancer early, we can enhance treatment efficacy and offer patients a greater chance of a successful outcome.

Summary

While penile cancer remains a rare malignancy, its impact on men's health and well-being cannot be overstated. It is important for men to be aware of the risk factors and symptoms associated with penile cancer and to seek medical advice early for the best possible prognosis. As research progresses, the future holds promise for even more refined treatments and increased survival rates.

Resources

American Cancer Society

“Chemotherapy for Penile Cancer”
(Last revised: June 25, 2018)
https://www.cancer.org/cancer/types/penile-cancer/treating/chemotherapy.html

“HPV and Cancer”
(Last revised: July 30, 2020)
https://www.cancer.org/cancer/risk-prevention/hpv/hpv-and-cancer-info.html

“Signs and Symptoms of Penile Cancer”
(Last revised: June 25, 2018)
https://www.cancer.org/cancer/types/penile-cancer/detection-diagnosis-staging/signs-symptoms.html

“Living as a Penile Cancer Survivor”
(Last revised: June 25, 2018)
https://www.cancer.org/cancer/types/penile-cancer/after-treatment/follow-up.html

“Local Treatments (Other than Surgery) for Penile Cancer”
(Last revised: June 25, 2018)
https://www.cancer.org/cancer/types/penile-cancer/treating/topical-therapy.html

“Risk Factors for Penile Cancer”
(Last revised: June 25, 2018)
https://www.cancer.org/cancer/types/penile-cancer/causes-risks-prevention/risk-factors.html

“Surgery for Penile Cancer”
(Last revised: June 25, 2018)
https://www.cancer.org/cancer/types/penile-cancer/treating/surgery.html

American Academy of Pediatrics

“Circumcision: Where We Stand”
(Last revised: February 12, 2024)
https://www.healthychildren.org/English/ages-stages/prenatal/decisions-to-make/Pages/Where-We-Stand-Circumcision.aspx

Cancer Research U.K.

“Sex and relationships with penile cancer”
(Last reviewed: January 18, 2021)
https://www.cancerresearchuk.org/about-cancer/penile-cancer/living-with/sex-relationships

Cleveland Clinic

“Penile Cancer”
(Last reviewed: May 19, 2022)
https://my.clevelandclinic.org/health/diseases/6181-penile-cancer

Healthline.com

Purdie, Jennifer
“Common Types of Human Papillomavirus (HPV)”
(Updated: June 26, 2023)
https://www.healthline.com/health/sexually-transmitted-diseases/hpv-types

National Cancer Institute

“Penile Cancer Treatment (PDQ^®)–Patient Version”
(Updated: May 12, 2023)
https://www.cancer.gov/types/penile/patient/penile-treatment-pdq

Urology Care Foundation

“Penile Cancer”
(no date)
https://www.urologyhealth.org/urology-a-z/p/penile-cancer

UpToDate

Pettaway, Curtis A., MD, and Pagliaro, Lance C., MD
“Carcinoma of the penis: Surgical and medical treatment."
(Topic last updated: October 23, 2023)
https://www.uptodate.com/contents/carcinoma-of-the-penis-surgical-and-medical-treatment

Stecca, C.E., Alt, M., Jiang, D.M. et al. Recent Advances in the Management of Penile Cancer: A Contemporary Review of the Literature. Oncol Ther 9, 21–39 (2021).
https://doi.org/10.1007/s40487-020-00135-z