Papillomas

Papillomas are benign epithelial tumours with a central core of branching connective tissue. Only squamous papillomas will be considered here. Common warts are squamous papillomas. These are caused by infection with HPV - human papillomavirus. Warts, or verrucae, are keratinized on the surface, but many other papillomas are not. Among hem are condylomas, laryngeal and oral papillomas, and sinonasal papillomas.

Sinonasal papillomas can be divided into squamous- and cylinder cell papillomas, and finally inverted papillomas. The squamous cell variant is caused by HPV, mainly type 6 and 11, but type 16 has also been found.

Condylomas are exophytic squmaous cell papillomas found in the anogenital region. They are most often caused by HPV type 6 and 11.

Laryngeal papillomas are exophytic squmaous cell papillomas found in the larynx, sometime speading to pharynx and trachea. The are caused y HPV type 6 and 11. Histologically they seem to be identical to genital exophytic condylomas, and it was resently shown that there is a strong correlation betwee patients with juvenile onset laryngeal papillomas AND the presence of genital condylomas in the mothers (her ska' laves en reference til Michael Silverberg: Human Papillomavirus Types 6 and 11, Genital Warts and Juvenile Onset Recurrent Respiratory Papillomatosis. Prospective Studies in the United States and Denmark. Doctoral Thesis, Baltimore, Maryland 2001).
See the series on laryngeal papillomas.

Focal Epithelial Hyperplasia - FEH. This condition is characterised by oral epithelial soft hyperplasias. Histological they do not resemble papillomas, but they always harbour HPV types 13 or 31.

Cervical cancer and HPV. It was unpredictable that the discovery of HPV in common warts would ever lead to a break-through in understanding and prevention of cervical cancer. However, Harald zur Hausen's reason for examining common warts back in the 1970s was actually a search for an infective that could play a role in the development of cancer.
I started working with HPV and laryngeal papillomas in 1983, but the DNA sequence of HPV-11, isolated from a laryngeal papilloma, was not published until 1986 by Dartmann et al. The number of new HPV-types was fast increasing in the period, and when HPV type 16 was found in cervical carcinomas (and later in penile cancers as well) the interest among scientists grew fast: for the first time was evidence for the cause of a major cancer disease presented. It took however many years to develop vaccine against HPV 16, but vaccination of women is now an ongoing program in Denmark and in other contries. A side-effect is that the vaccine also protects against HPV types 6 and 11, so in the future the number of patients with genital condylomas and laryngeal papillomas is expected to decrease.
Today we know that cervical carcinomas do not develop unless an infection with HPV 16 (or other of the so-called high-risk HPV types) has been present. But we also know that the majority of women with HPV-16 (or other high-risk types) will never develop cervical cancer.