This excision consists of a clearly exophytic tumor composed of numerous papillary fronds.
The papillae are lined by a multilayered squamous epithelium which has undergone dysplastic change. There are enlarged nuclei with disordered maturation and significant crowding, features which are beyond that of the expected mild dysplasia typical of HPV.
The squamous epithelium shows no maturation at all, consistent with a high grade dysplasia. Additionally, there are mitoses near the surface.
Mitoses are numerous and involve all layers of the epithelium.
The non-keratinizing papilloma of the larynx can be divided in those arising in adults or those in children. Human papillomavirus types 6 and 11 have been associated with benign laryngeal papilloma.
The overall incidence of developing carcinoma in these lesions is about 2%, unless there is a history of radiation, which increases this number to 14%. Transformation to squamous cell carcinoma may result in loss of the HPV expression. One report indicated that HPV-11 was the only type of HPV in all lesions comprising the morphologic spectrum of papillomatosis progressing to carcinoma (Lele).
Pharmacologic approaches (hormones, local corrosives, alkylating agents, interferon), physical methods (electrocautery, ultrasound, laser, cryotherapy), and surgical therapy, such as laser excision or microresection under microscope and open surgery (Green)
Despite surgical resection, papillomas tend to spread to surrounding tissues and recur. The treatment of choice is complete resection of the lesion while preserving the respiratory tract and protecting the voice. Lung and laryngeal carcinomas that may develop are often diagnosed at a late stage with resultant low survival rates.
Green, GE, Bauman, NM and Smith, RJ. (2000) Pathogenesis and treatment of juvenile onset recurrent respiratory papillomatosis. Otolaryngol Clin North Am 33 , pp. 187-207.
Lele SM, et al. Molecular events in the progression of recurrent respiratory papillomatosis to carcinoma. Arch Pathol Lab Med. 2002 Oct;126(10):1184-8.