What is Recurrent Respiratory Papillomatosis?
Recurrent respiratory papillomatosis (RRP or laryngeal papillomatosis) is a medical condition affecting the voice box (larynx) and vocal cords. Although it is benign (not cancerous) it can severely impact ones quality of life. The condition is caused by infection with specific subtypes (6 and 11) of the Human Papilloma Virus (HPV). The HPV virus is common and is known to cause growths elsewhere in the body including genital warts and cervical cancer.
Who gets RRP and what causes it?
RRP can occur at different stages in life. The juvenile onset form of recurrent respiratory papillomatosis (JoRRP) affects children at the average age of 4 years old. It is thought to be cause by transmission of HPV virus from mother to baby during childbirth. The risk of developing the disease is increased if the mother has genital warts, in younger mothers and in first-born children. Even if a mother has active genital warts the risk of the child developing RRP is very low (1:300). Delivery by caesarean section does not always protect against transmission of the HPV virus.
The adult form has two peaks of incidence – in the 20 – 30 year old group and in the 50-60 year old group. It is thought to be possibly sexually transmitted – although this is unclear and not always the case. There may be a long lag period between contracting the virus and developing lesions. Only a small percentage of people exposed to HPV develop laryngeal lesions and they may have an underlying problem with their immunity, as most people exposed to HPV are able to clear the virus naturally.
Why are the symptoms of RRP?
Patients affected by RRP develop mushroom like growths on the vocal cords and voice box, which affect their ability to speak. Presentation is with a progressively husky or hoarse voice that does not improve over time. Sometimes the growths become so large that the breathing can be affected. In this case people may complain of noisy breathing or difficulty breathing. The growths can become larger over time causing worsening of voice or breathing.
Children may present with a hoarse cry or hoarse speech, which is why every child with a hoarse voice should be assessed to exclude this disease. In more severe cases, children can present with difficulty breathing, which may require urgent and repeated surgical treatments to debride or reduce the bulk of the disease. Sometimes the disease can spread into the windpipe and beyond into the lungs. HPV subtype 11 is thought to represent a more severe form of disease in children.
How is the diagnosis of RRP made?
RRP is diagnosed by visualizing the voice box (larynx) with a telescope introduced via either the nose or the mouth (laryngoscopy). Advanced technologies including stroboscopy and narrow band imaging can improve diagnostic accuracy when dealing with RRP. The diagnosis is conformed by taking a biopsy whereby a small tissue sample is sent to the laboratory for examination under a microscope. Special tests can be performed to help identify which subtype of HPV is responsible for the disease appearing. This can give some prognostic information.
What is the treatment for RRP?
Treatment is aimed at restoring voice and breathing function and reducing the rate of recurrence. Surgical treatment under general anaesthetic is initially necessary to take a biopsy and confirm diagnosis and assess degree of spread into the lungs. Surgery is designed to debulk visible lesions. There are many methods of removing papilloma lesions including cold steel resection, use of a microdebrider machine and laser resection. Care must be taken not to damage normal tissue and induce irreversible scar, which may make the voice permanently worse or obstruct the breathing. The KTP laser is a new kind of treatment designed to cause minimal collateral damage to normal tissues by targeting the blood supply of the papilloma. Typically the papilloma lesions recur over time as surgery is unable to eliminate the virus from surrounding infected cells and people usually require multiple surgeries until their immune system clears the virus naturally.
Many medical treatments have been tried however there is no one good agent which is able to cure RRP. Some affected people report than Indole-3-carbiole (I3C) or Diindylemethane (DIMM), which are natural extracts of broccoli and cauliflower can help to reduce disease severity whilst these supplements are being taken. There is a promising new agent, also used in treatment of cancer, which targets the growth of new blood vessels into the papilloma to slow down their growth.
Dr Novakovic and the team at Sydney Voice and Swallowing have expertise in the diagnosis and treatment of Recurrent Respiratory papillomatosis of the larynx with information about the latest available therapies. Dr Novakovic is the leader of the team that runs the Australian study investigating the impact of the National HPV vaccination program on the disease burden of RRP in Australia. Dr Novakovic has published multiple journal papers on RRP and has been invited to National and International scientific meetings to speak on the topic as a recognized expert in the field.