INTRODUCTION: Recurrent respiratory papillomatosis (RRP) is a benign, often multifocal neoplasm caused by the human papilloma virus (HPV), characterized by the formation of recurrent, epithelial neoplastic lesions in the larynx, but in 2 to 5% of the cases can affect the lower airways where they can produce airway obstruction. Treatment usually involves repeated surgical debulking with carbon dioxide (CO2) laser or the microdebrider with medical interventions reserved as adjuvant therapies. We describe a case with RRP involving all the distal airways using a combination of argon plasma coagulator (APC) and intralesional cidofovir.
CASE PRESENTATION: A 60 year old male presented with a five year history of progressive dyspnea and wheezing. An outside bronchoscopy reported partial obstruction of both main bronchus by multiple endobronchial lesions. Two different biopsies confirmed the diagnosis of RRP. His physical exam was remarkable for the presence of dyspnea at rest and bilateral wheezing. Our initial bronchoscopy showed a near complete obstruction of both main bronchus due to tumor growth (Figure 1 A and B), which extended to all the distal airways (Figure 1 C and D). APC was used to successfully desiccate all the intrabronchial lesions. Once the airways were patent (Figure 2) we used a Wang needle to inject cidofovir into the few visible lesions encrusted on the bronchial walls. The patient had a complete resolution of his symptoms and remains asymptomatic with repeat bronchoscopy performed at 18 and 36 months showed no recurrence of endobronchial lesions.
DISCUSSIONS: The treatment of the RRP lesions is challenging and usually involves repeated surgical debulking with CO2 laser or increasingly with the microdebrider. Adjuvant treatments include cidofovir, indole-3-carbinol, ribavirin, mumps vaccine, and photodynamic therapy. As illustrated in this case, APC can be used as an alternative treatment for RRP. The APC uses a high frequency electric current fed from a probe tip, that fits inside the working channel of the bronchoscope, through ionized argon plasma that causes superficial thermal coagulation of tissue. Argon flow was set between 0.5 and 1.0 L/min, and the current between 40 to 60 Watts. The probe was placed between 3 and 5 mm from and in a tangential position to the lesion of interest. Coagulation was activated by a foot pedal and repeatedly applied for 1- to 5-seconds intervals until the lesion appeared to be desiccated. Loose debris was removed with suction or forceps. Because argon coagulation is dependent on the water content of the targeted tissue, desiccation of the treated area prevents deeper thermal effect and damage to underlying structures. The APC offers significant advantages, including tissue damage is mild and predictable, argon coagulation does not result in tissue carbonization or vaporization, and can be used in the distal airways. It is cheaper than CO2 laser and requires much less training. There are only two reports of the use of APC in RRP but in both cases papillomas were limited to the trachea [1, 2]. Our report is unique in two aspects: first it describes an extreme case of RRP with involvement of all the segments of all the distal airways and second, this is the first report in which combination of APC and intralesional cidofovir is used.
CONCLUSION: APC may be an alternative for the treatment of RRP, especially with distal airway involvement. Whether the concomitant use of intralesional cidofovir will be effective requires further studies.
DISCLOSURE: Vichaya Arunthari, No Financial Disclosure Information; No Product/Research Disclosure Information