A papilloma is a benign growth that forms on the surface of skin or the lining of internal organs, driven by the abnormal proliferation of epithelial cells. Most papillomas are caused by human papillomavirus (HPV), though some arise without any clear viral trigger. The word covers a surprisingly wide family of growths, from a painless wart on your finger to a tumor inside a breast duct or a mass on the vocal cords, and the path from diagnosis to treatment looks different depending on where the papilloma shows up and what caused it.
How HPV Drives Most Papillomas
Human papillomavirus is one of the most common viral infections on the planet. There are more than 200 known HPV types, and many of them specifically target epithelial cells, the flat, tightly packed cells that line your skin, throat, and internal surfaces. Once HPV infects an epithelial cell, it hijacks the cell’s replication machinery to copy its own DNA. That forced cell division is what produces the characteristic outward or inward overgrowth we call a papilloma. A comprehensive review of skin lesions caused by HPV, covering 135 studies from 2000 to 2023, described the virus as “omnipresent” and noted that its effects range from harmless warts to malignant skin growths.1PubMed Central. Skin Lesions Caused by HPV-A Comprehensive Review
Not every papilloma is HPV-related, though. Intraductal papillomas of the breast, for instance, grow from the cells lining the milk ducts and have no established viral cause. Choroid plexus papillomas in the brain arise from the tissue that produces cerebrospinal fluid, and they are not linked to HPV either. So while the virus explains the majority of papillomas you are likely to encounter, the term itself is anatomical rather than viral: it simply describes a finger-like or cauliflower-like projection of epithelial tissue, whatever kicked off the growth.
How the Virus Avoids Your Immune System
If HPV is so common, you might wonder why your immune system does not just clear it before a papilloma ever forms. In most people, it eventually does. But HPV has evolved a set of tactics that buy it time. The virus keeps a low profile by confining its activity to the outer layers of skin or mucosa, where immune surveillance is weaker. It also actively blocks pathways the immune system relies on to detect infected cells, including the molecular machinery that flags abnormal proteins on a cell’s surface.2PubMed Central. Mechanisms of virus immune evasion lead to development from chronic inflammation to cancer formation associated with human papillomavirus infection By suppressing key inflammatory signals, HPV can persist in tissue for months or years without triggering a strong immune response.3PubMed Central. Papillomavirus Immune Evasion Strategies Target the Infected Cell and the Local Immune System
This immune evasion is a big part of why some papillomas keep coming back after treatment. The virus can linger in nearby tissue at levels too low to detect, and once conditions shift, it reactivates and drives new growths. In people with weakened immune systems, the problem tends to be worse, with papillomas appearing in greater numbers, growing faster, and recurring more stubbornly after removal.
Skin Papillomas and Common Warts
The papillomas most people are familiar with are ordinary skin warts. Common warts (verruca vulgaris), plantar warts on the soles of the feet, and flat warts on the face or hands are all papillomas driven by specific HPV types. They spread through direct skin-to-skin contact or by touching contaminated surfaces like gym floors or shared towels. Most are painless, though plantar warts can hurt because of pressure from walking.
The majority of skin warts clear on their own within a year or two as the immune system catches up with the virus. Over-the-counter treatments containing salicylic acid work by peeling away layers of the wart over several weeks. Cryotherapy, where a clinician freezes the wart with liquid nitrogen, is another standard option. For stubborn warts, clinicians sometimes turn to prescription topicals or minor surgical removal.
A question that comes up regularly is whether the HPV vaccine, designed to prevent cervical and other cancers, also helps with ordinary warts. A study in pediatric patients found no significant link between vaccination status and whether warts resolved.4PubMed Central. HPV Vaccination Status and Resolution of Warts in Pediatric Patients That makes sense because the vaccine targets the HPV types most associated with cancer, not the types that cause most common warts. So the vaccine is still tremendously valuable, just not as a wart remedy.
Oral Papillomas
Papillomas also grow inside the mouth, typically appearing as small, painless, finger-like projections on the tongue, inner cheek, gums, or palate. They tend to be white or pink and are usually solitary. Oral papillomas are almost always benign and rarely recur after removal.
Excision is the standard treatment, and clinicians increasingly use laser surgery rather than a traditional scalpel. A case report comparing CO₂ laser removal to scalpel excision of oral papillomas on opposite sides of the tongue in the same patient found that both methods produced comparable tissue specimens for pathological examination. Interestingly, the scalpel side healed slightly faster with less postoperative discomfort.5PubMed. Papilloma excision. Scalpel or CO2 Laser? A case report A separate report on a lingual papilloma treated with a diode laser noted uneventful healing at one month, with the laser offering advantages like built-in wound sterilization and no need for sutures.6PubMed Central. The Efficacy of Low-Level Laser Therapy in Treating Oral Papilloma: A Case Reporting A Lingual Location In practice, the choice between scalpel and laser often comes down to the clinician’s equipment and preference; both work well for these small growths.
Intraductal Papillomas of the Breast
Intraductal papillomas are wart-like growths that form inside the breast’s milk ducts. They are the most common cause of spontaneous nipple discharge, especially when the discharge is clear or blood-tinged. In a large retrospective study of 4,450 intraductal papilloma cases, roughly 37% of patients had nipple discharge, about 51% had a palpable breast mass, and around 28% had only mild discomfort or no symptoms at all.7PubMed Central. A retrospective observational study of intraductal breast papilloma and its coexisting lesions: A real‐world experience
Because breast papillomas can coexist with atypical cells or even carcinoma, any lump or unexplained nipple discharge warrants imaging. Ultrasound is typically the first step, but MRI outperforms it significantly. One study comparing the two in 243 cases found ultrasound detected roughly 65% of papillomas while MRI detected about 99%.8PubMed Central. The role of magnetic resonance imaging in detection and surgical treatment of breast intraductal papillomas Even with strong imaging, a tissue biopsy is usually needed to confirm the diagnosis and rule out cancer. Treatment for solitary papillomas often involves surgical excision, particularly when they are associated with atypia. Small, clearly benign papillomas discovered incidentally may be monitored with follow-up imaging instead.
Recurrent Respiratory Papillomatosis
Recurrent respiratory papillomatosis, or RRP, is one of the more disruptive forms of this condition. Papillomas grow on the vocal cords and surrounding airway tissue, causing hoarseness, breathing difficulty, and in severe cases partial airway obstruction. RRP is caused by HPV types 6 and 11, the same low-risk types responsible for most genital warts. Children can acquire the virus during birth if the mother has an active infection; adults can develop it later in life, sometimes decades after initial exposure.
The frustrating hallmark of RRP is recurrence. Papillomas are surgically removed, often with a microdebrider or laser, and they grow back. Some patients require dozens of procedures over a lifetime. Adjuvant therapies have been explored to slow regrowth. Intralesional injection of cidofovir, an antiviral drug, has shown promise as an add-on after surgical debulking.9PubMed. Squamous cell carcinoma associated with intralesional injection of cidofovir for recurrent respiratory papillomatosis More recently, the immunotherapy bevacizumab and systemic antiviral agents have entered clinical trials, though no single adjuvant treatment has eliminated recurrence entirely.
RRP takes a real toll beyond the physical symptoms. A study measuring health-related quality of life in children with RRP found a mean health utility score of 0.76 on a 0-to-1 scale, along with marked impairment in voice-related quality of life and significant psychosocial strain on families.10PubMed. The quality of life and health utility burden of recurrent respiratory papillomatosis in children For context, a score of 1.0 represents perfect health. Repeated surgeries, voice changes, and chronic uncertainty weigh heavily on patients and caregivers alike.
Sinonasal Inverted Papillomas
Inside the nasal cavity and paranasal sinuses, a specific type called an inverted papilloma grows inward into the underlying tissue rather than projecting outward. These are relatively uncommon but deserve attention because they behave more aggressively than typical papillomas. Symptoms usually include one-sided nasal obstruction, sometimes with blood-tinged discharge or a reduced sense of smell.
Surgical removal is the standard treatment, usually via an endoscopic approach. But recurrence rates are high. A study of 44 patients who underwent surgery for sinonasal inverted papilloma found that about 34% experienced recurrence, with regrowth appearing on average around two years after the initial operation. Malignant transformation, where the papilloma progressed to squamous cell carcinoma, occurred in roughly 14% of cases.11PubMed Central. Sinonasal inverted papilloma: rate of recurrence and malignant transformation in 44 operated patients That cancer risk is why long-term follow-up with periodic imaging is critical after removal. If you have had a sinonasal inverted papilloma taken out, surveillance appointments are not optional.
Papillomas of the Urinary Tract
Papillomas can grow in the bladder and ureters, arising from the urothelium, the specialized lining of the urinary tract. An inverted urothelial papilloma appears on cystoscopy as a smooth, stalk-like mass projecting into the bladder. Under the microscope, the growth pattern is endophytic, meaning the tumor grows inward beneath a surface layer of urothelial cells. The cells themselves look bland and uniform, with no significant mitotic activity.12PubMed Central. Inverted urothelial papilloma: A review of diagnostic pitfalls and clinical management
The main diagnostic challenge here is distinguishing a benign inverted papilloma from low-grade urothelial carcinoma, which can look similar on initial inspection. A pathologist’s evaluation of the tissue biopsy is essential. True inverted papillomas have an excellent prognosis and a low risk of recurrence after complete removal, but misdiagnosis can lead to either unnecessary treatment or, worse, missed cancer. That diagnostic ambiguity means most urologists treat any suspicious bladder growth with a transurethral resection, which serves as both biopsy and treatment in one step.
Choroid Plexus Papillomas
Among the rarest papilloma types are choroid plexus papillomas, benign tumors that grow from the tissue inside the brain’s ventricles responsible for producing cerebrospinal fluid. These mostly appear in infants and young children. The tumor’s danger comes not from malignancy but from overproduction of cerebrospinal fluid, which can cause hydrocephalus, a dangerous buildup of pressure inside the skull. A case report described an infant whose choroid plexus papilloma produced enough fluid to form a large cyst; initial drainage through a shunt provided temporary relief, but definitive treatment required surgical excision of the tumor itself.13PubMed. Choroid plexus papilloma producing symptoms by secretion of cerebrospinal fluid
Complete surgical removal is curative in most cases. The challenge is the delicate location. These tumors sit deep in the brain’s fluid-filled chambers, and the surgery requires careful navigation to avoid damaging surrounding structures. Outcomes have improved significantly with modern neurosurgical techniques and imaging, and recurrence after total removal is uncommon.
When Papillomas Turn Cancerous
Most papillomas stay benign, but a minority can progress to cancer. The risk depends heavily on the type and location. Certain high-risk HPV types, especially types 16 and 18, are well established as causes of cervical, throat, and anal cancers. The mechanism involves viral proteins that interfere with tumor-suppressor genes in the host cell, pushing the cell toward genomic instability and eventually malignant transformation.14PubMed Central. Molecular mechanisms of human papillomavirus-induced carcinogenesis
Sinonasal inverted papillomas carry a meaningful cancer risk, as noted above. Breast papillomas with atypical cells raise the risk of subsequent breast cancer enough that excision is generally recommended. For common skin warts and most oral papillomas, malignant transformation is extremely rare. RRP occasionally progresses to squamous cell carcinoma, particularly in patients with HPV type 11 and a long history of disease.
The practical takeaway is that a papilloma’s location and HPV type matter more than the word “papilloma” itself when assessing cancer risk. Your clinician’s recommendation for follow-up surveillance versus one-and-done removal should reflect that nuance.
The Psychosocial Side of HPV-Related Papillomas
The physical symptoms of papillomas get most of the attention, but the emotional burden is real and often underappreciated, particularly for genital warts and recurrent respiratory disease. A UK observational study found that younger adults with genital warts reported significantly lower health-related quality of life compared to age-matched population norms, with the impact especially pronounced in 18- to 24-year-olds.15PubMed Central. Impact of human papillomavirus-related genital diseases on quality of life and psychosocial wellbeing: results of an observational, health-related quality of life study in the UK Shame, anxiety about transmission, and worry about cancer risk contributed to the reduced wellbeing. For children with RRP and their families, repeated surgical interventions and voice impairment create ongoing stress that standard clinical visits rarely address in depth.
If you or a family member is dealing with recurrent papillomas of any kind, it is worth raising the psychological dimension with your care team. Support groups exist for both RRP and HPV-related conditions, and brief psychological interventions have been shown to help with the anxiety and stigma that often accompany these diagnoses.
Papillomas in Dogs, Cats, and Other Animals
Papillomas are not a uniquely human problem. Papillomaviruses infect a wide range of species, and the lesions they cause in animals mirror many of the patterns seen in people. In dogs, oral papillomatosis, clusters of wart-like growths inside the mouth, is common in puppies and young dogs with immature immune systems. It is caused by canine papillomaviruses, of which 24 types have been identified so far. Most canine oral papillomas regress on their own as the dog’s immune system matures, though occasionally they persist or, rarely, progress to squamous cell carcinoma.16PubMed Central. Canine and feline papillomaviruses: an update
Cats have their own set of feline papillomaviruses, six types identified to date. Feline papillomavirus type 2 is particularly noteworthy because of its association with a subset of malignant skin lesions in cats, making it an emerging concern in veterinary oncology.17PubMed. An Update on Canine, Feline and Bovine Papillomaviruses Bovine papillomaviruses affect cattle worldwide and can cause economically significant disease, including large skin warts that interfere with milk production and hide quality. Crucially, animal papillomaviruses do not cross over to humans. Your dog’s mouth warts are not a risk to you, and your wart is not a risk to your dog. Each species’ papillomaviruses are adapted to their specific host.