Biopsy showed a raised papillary verrucous lesion with papillae lined by squamous epithelium showing hyperkeratosis, focal parakeratosis and acanthosis with a central fibrovascular core. No koilocytes were seen.

Squamous papilloma of the vulva.

Discussion

Squamous papilloma of the vulva is a benign epithelial neoplasm commonly seen in about 1% of middle-aged women. ^[1] Altmeyer et al.[2] first described these small projections as pseudocondylomata of the vulva. It has been reported under a variety of names such as benign squamous papillomatosis, ^[3] vulval squamous papillomatosis, vestibular papillomatosis, hirsuties papillaris vulvae, hirsutoid papillomas of the vulva, micropapillomatosis labialis and squamous vestibular micropapilloma. The abundance of names reflects the uncertain origin of this condition. Squamous papilloma usually presents as a solitary verrucous exophytic growth on the vulvar vestibule. It is often considered to be a variant of skin tags by some authors. Although usually asymptomatic, rarely, it may be associated with pruritus and a burning sensation.

The significance of vulvar squamous papillomatosis is subject to controversy. Some authors consider the lesions as normal anatomical variants of the vestibular mucosa. ^[4],[5],[6] Others, however, believe that the lesions are human papilloma virus-associated as they resemble genital warts, ^[7] Of late, various molecular biology techniques have been used to clarify the origin of squamous papilloma, but the results have not been unanimous.

In order to facilitate the differentiation between vestibular papillomatosis and genital warts, several clinical parameters have been proposed by Moyal-Barracco et al. ^[8] Vestibular papillae are pink-colored (same as that of adjacent mucosa), soft, linear and symmetrically distributed. The base of individual vestibular papillae projections remain separate and no circumscribed whitening is seen by the acetic acid test. Condyloma acuminatum, on the other hand, is firm and randomly localized. The color of the condyloma acuminatum lesions can vary and individual papillary projections often coalesce in a common base. In most cases of condyloma acuminate, whitening can be observed by the acetic acid test. ^[8]

Apart from a condyloma acuminata, other differential diagnosis considered in our patient were bowenoid papulosis and seborrhoeic keratosis, each of which were aptly excluded by the absence of typical histological findings such as koilocytes and keratin horn cysts. In our patient, the typical bilateral distribution of squamous papilloma was not seen. Our patient being retrovirus positive had only a unilateral distribution of hyperpigmented soft warty lesions on the labia majora. Because the lesions were asymptomatic and not of much concern to the patient, no treatment was offered.