Introduction

Small, benign growths called pearly penile papules (PPP) grow on the edge of the penis. It is common for people to confuse them with an STI. They mainly affect young people assigned male at birth (AMAB)going through puberty and have no symptoms. PPP are similar to small fibrous growths found elsewhere on the body. They might appear after puberty and could be linked to increased sexual activity, but this isn't certain. It's important to tell PPP apart from other penile conditions like genital warts, sebaceous glands, molluscum contagiosum, and lichen nitidus, which have distinct features that can be identified through tissue examination.

Various treatments for PPP have been tried, including freezing, electric current, scraping, and laser treatments. However, these can cause scarring, and often the best approach is reassurance.¹

Aetiology

The specific aetiology (cause) of PPP remains undetermined. However, research indicates that it may be associated with benign growths called acral angiofibromas, which have similarities to other skin disorders such as adenoma sebaceum and fibrous papules that are seen in other body areas. Earlier theories suggested links to smegma (a natural secretion), or sexual activity, but these ideas have been disproven. 

PPPs appear more often after puberty and tend to decrease with age, indicating a possible link to hormonal changes. PPPs are considered benign growths with no known underlying pathology. They are believed to be a normal variant of penile anatomy rather than the result of an infection or disease, though their specific etiology is unknown. Because PPPs usually occur in late adolescence or early adulthood, research indicates that they may be related to family history or hormonal changes during puberty.²

Possible causes

• Hormonal Changes: PPPs often appear after puberty, suggesting that hormones might play a role in their development. The growth of these papules may be triggered by hormonal changes during puberty
• Genetics: there might be a genetic predisposition to developing PPPs, as they tend to run in families. However, the specific genes responsible haven't been identified yet
• Skin Type: PPPs are more common in uncircumcised men and noted to be more prevalent in certain racial groups, such as those of African descent. Still, the precise genes likely involved remain unidentified
• Skin Variation: PPPs are considered a normal variation in the skin, especially in certain populations. They are usually harmless, mainly seen in boys going through puberty and young men
• Penile Anatomy: some theories suggest that variations in penile anatomy, such as the shape or size of the glans penis (the rounded head of the penis), could contribute to the formation of PPPs
• Race and Circumcision Status: PPPs are more commonly observed in uncircumcised individuals and those of African descent, suggesting that race and circumcision status may be associated with their development

Description of PPPs' appearance

Pearly penile papules, also known as pearly-white, pink, or yellowish-colored bumps, typically appear as small, cylindrical or thread-like lumps. Their diameter and height usually vary between 1 and 2 mm. These bumps are often arranged in rows around the edge of the glans penis, though they may sometimes encircle the glans entirely. Under a dermatoscope, PPPs show a characteristic grape-like or cobblestone pattern, with each bump having a central vessel structure surrounded by crescent-shaped rims.³

Medical examination and diagnosis

PPPs are diagnosed through a clinical examination and dermatoscopic evaluation, with dermoscopy confirming their appearance. If uncertain, a biopsy may be performed, but this is rarely necessary. PPPs are diagnosed through a combination of clinical assessment, differential diagnosis, and additional tests to confirm the lesions' nature and provide patient comfort.

Clinical Examination

• Visual Inspection: PPP are usually diagnosed based on their characteristic appearance. They appear as small, dome-shaped, or thread-like bumps around the rim of the glans penis, often arranged in one or two rows
• Location and Distribution: PPP are commonly found on the rim of the glans penis, though they can also occur on the shaft

Differential diagnoses

• Genital Warts: PPP are often mistaken for genital warts, which are caused by human papillomavirus (HPV) infection
• Tyson's Glands: these are modified sebaceous glands found in the frenulum of the penis. Unlike PPP, Tyson's glands are not mainly found around the rim of the glans penis and have a glandular component.⁹

Additional Diagnostic Tests

• Dermoscopy: dermoscopy can help diagnose PPP by revealing characteristic features such as a cobblestone or grape-like pattern with central dotted or comma-shaped vessels. This may assist in differentiating PPP from other conditions with similar appearances, such as genital warts
• Histological Examination: though not usually necessary for diagnosis, a biopsy may be performed when the diagnosis is uncertain or other conditions are suspected⁷

Treatment

Most cases of PPP do not require any treatment, however, options exist for when treatment is desired or needed

• Topical Therapies: topical corticosteroids are used for inflammatory lesions like lichen sclerosus, but prolonged use can cause skin thinning. Topical treatment with 5-FU is successful, however surgery might be recommended
• Surgical Excision-Based Treatments: circumcision is recommended for isolated preputial lesions and lichen sclerosus to relieve symptoms and reduce a pro-carcinogenic environment. For certain kind of tumors with negative margins organ sparing surgery is recommended
• Other Thermal Modalities: cryoablation, electrocautery, and laser ablation are effective for non-cancerous lesions, though their effectiveness for cancerous lesions is debated
• Cryotherapy: cryotherapy, a common treatment for skin lesions, may not be the best option for PPP treatment due to potential complications like scarring and pain
• Electrodessication and Curettage (ED&C): This method involves scraping the papules with a curette and cauterizing them with an electric current, potentially causing cosmetic effects like scarring, pain, and skin color changes
• Laser Therapy: Laser therapy is a promising alternative for PPP treatment. Specifically, erbium:yttrium-aluminum-garnet (Er:YAG) and CO2 lasers were the most commonly used in studies reviewed. Laser therapy offers precise targeting, minimal damage to surrounding tissues, and potentially better cosmetic outcomes compared to traditional methods like cryotherapy and ED&C
  • Erbium:YAG Laser: this type of laser emits light at a wavelength that is well absorbed by water, making it suitable for precise tissue removal. These lasers have been reported to clear PPP lesions with some discomfort and complications
  • CO2 Laser: this type of laser is also commonly used for skin resurfacing and tissue removal. It has shown effectiveness in PPP treatment with minimal adverse effects reported.⁸
  • Pulsed Dye Laser: this type of laser targets blood vessels and can be used for various skin conditions. While not as commonly reported, it has shown promise in PPP treatment
  • Fractional Photothermolysis: This approach involves targeting microscopic columns of tissue, leaving surrounding areas intact. It has been used in PPP treatment with favorable outcomes.^4,5

Prognosis

The prognosis of PPP is influenced by the patient's compliance, therapy efficacy, and disease stage. Low-risk patients usually have an acceptable prognosis, although careful observation is necessary. Although surgical excision-based treatments have good long-term results, there may be a higher rate of recurrence with some techniques. Complications like skin thinning or recurrence require prompt monitoring and intervention.⁶

Research and advancements in PPP management

• Advancements in topical therapies, surgical techniques, and thermal modalities continue to improve the management of PPPs
• Research is ongoing to develop more effective and targeted therapies with fewer side effects for benign and malignant penile lesions
• Studies evaluating the effectiveness and long-term outcomes of newer treatments, such as laser therapies and immune-modulating agents, are needed to optimize PPP management
• Collaborative efforts between clinicians and researchers are essential to advance understanding of PPPs and develop innovative strategies for prevention, diagnosis, and treatment¹⁰

Summary

Pearly Penile Papules (PPP) are non-cancerous tumours that appear on the outer edge of the penis. They have been documented throughout history, with early misconceptions about their nature gradually dispelled through tissue examination. PPP typically appear in boys going through puberty and young men, often arranged in rows and ranging from 1 to 4 mm in size. While their exact cause is not fully understood, hormonal changes and genetic factors may play a role in their development. PPP are sometimes misdiagnosed as sexually transmitted infections (STIs) despite their benign origin, leading to needless anxiety. Clinical examination, differential diagnosis, and occasionally dermoscopy or biopsy are all necessary for a proper diagnosis. Assurance, topical medications, and procedural treatments including laser therapy or surgical excision are available as forms of treatment. PPPs have a favorable outcome overall when appropriately managed and monitored.

It's critical to get medical help right away if there are any strange growths or changes in the genital area. Even though PPP are benign and often harmless, they can have symptoms that are comparable to those of other illnesses, such as genital warts. Speaking with a healthcare provider ensures that you receive the right diagnosis and treatment, giving the peace of mind and protecting general sexual health.

Understanding PPPs and differentiating them from other conditions is crucial for maintaining overall sexual health and well-being. While PPP may cause concern due to their appearance, they do not pose a threat to sexual health or function. Open communication with healthcare providers, accurate diagnosis, and education about PPP can help alleviate anxiety and promote a positive attitude towards sexual health. Remember, seeking medical advice and being proactive about your health is key to ensuring a fulfilling and healthy sex life.