Recurrent respiratory papillomatosis (RRP) is a rare, chronic medical condition defined by the development of benign, wart-like tumors, known as papillomas, within the respiratory tract. The disease is characterized by the repeated growth of these tumors. While these growths can appear anywhere from the nose and mouth down to the lungs, they most frequently occur in the larynx (voice box). This localization on the vocal cords causes the most common and disruptive symptoms.
Understanding Recurrent Respiratory Papillomatosis
Papillomas are noncancerous growths that form on the lining of the respiratory tract. The majority of these growths cluster on the vocal cords, which is why the condition is sometimes referred to as laryngeal papillomatosis. Their presence mechanically interferes with the precise vibrations of the vocal cords necessary for producing sound.
The word “recurrent” highlights the most challenging feature of this disease, as the papillomas return even after removal. The underlying virus persists within the tissue, causing new growths to develop rapidly, sometimes within weeks of a procedure. These soft, fleshy tumors can progressively narrow the airway, creating a physical obstruction that makes breathing difficult.
The Cause: Human Papillomavirus
The direct cause of RRP is infection with the Human Papillomavirus (HPV), specifically the low-risk types 6 and 11, which account for approximately 90% of all cases. These viral types are distinct from the high-risk HPV types associated with certain cancers.
RRP presents in two main forms. Juvenile-Onset RRP (JORRP) is diagnosed before age 12 and is the more severe form. JORRP is typically acquired through vertical transmission from an infected mother during childbirth.
In contrast, Adult-Onset RRP (AORRP) appears later in life, often peaking in a person’s fourth decade. The exact transmission route for AORRP is less understood, but it may relate to sexual contact or the re-activation of a dormant infection. Infection with HPV type 11 is associated with a more aggressive and rapidly recurring disease course than HPV type 6, often requiring more frequent surgical interventions.
Recognizing Symptoms and Diagnosis
The symptoms of RRP are directly related to the physical location and size of the papillomas. The most common sign is persistent hoarseness, which occurs when the growths distort the vocal cords’ ability to vibrate normally. In infants, this may manifest as a weak or abnormal cry that progressively worsens.
As the papillomas increase in size, they can narrow the airway, leading to obstruction. This can result in stridor, a high-pitched, noisy breathing sound noticeable when inhaling. Because these symptoms can mimic conditions like asthma, diagnosis requires specialized visualization.
The definitive diagnosis of RRP is made by visualizing the growths using laryngoscopy or bronchoscopy. During this examination, a doctor uses a scope to directly observe the lesions in the larynx and surrounding tissues. A biopsy is often taken to confirm the diagnosis and to check for any signs of malignant transformation.
Current Treatment Approaches
RRP is managed rather than cured, as current treatments do not eradicate the persistent HPV infection. The primary goal of treatment is to maintain a safe and open airway while preserving the quality of the patient’s voice. This is achieved through the surgical removal, or debulking, of the papillomas.
Surgical removal, or debulking, is achieved using various techniques. These include specialized instruments like the microdebrider, which mechanically shaves away the growths. Laser ablation techniques, such as the CO2 or KTP laser, are also common, targeting the blood vessels supplying the papillomas to destroy the tissue.
The chronic nature of the disease necessitates repeated surgical procedures, often occurring multiple times per year to keep the airway clear. For patients with aggressive disease that recurs frequently, adjuvant medical therapies may be used in combination with surgery to slow the rate of regrowth. These therapies include intralesional injection of antiviral drugs (like cidofovir) or anti-angiogenic agents (like bevacizumab). These medications are injected directly into the papillomas to extend the time interval between surgical procedures.
Long-Term Management and Outlook
RRP is a lifelong disease requiring continuous monitoring and management due to the high likelihood of recurrence. The frequency of surgical procedures is highly variable, often averaging four to five surgeries annually, creating a significant burden on patients and their families.
While most papillomas remain benign, serious long-term complications exist. These include distal spread, where the growths affect the trachea and lungs. There is also a rare risk of malignant transformation into squamous cell carcinoma, with rates estimated between 1% and 7%.