Introduction
Vulvar lichen planus (LP) is an inflammatory disorder that affects
mucocutaneous tissues, including vulva, vagina and other non-genital
regions, such as oral mucosa, skin and esophagus. LP has an estimated
prevalence of 0.5-3.7%, with erosive LP being the most prevalent form.
The etiology of this condition is still not fully understood, but it is
considered to be an autoimmune disease with a T-cell-mediated
pathogenesis, with a possible role for some exogenous factors, such as
nonsteroidal anti-inflammatories and antihypertensive
drugs.1
Vulvar squamous cell cancer (VSCC) can arise from two independent
premalignant pathways: a) one HPV related (30-50% of all cases), and
having high-grade squamous intraepithelial lesions (HSIL) as the
precursor lesion; b) the other, HPV independent, related to vulvar
dermatosis (lichen sclerosus), and having differentiated vulvar
intraepithelial neoplasia (dVIN) as the precursor
lesion.2–6 While those two pathways present as
concurrent in VSCC carcinogenesis, there are reports of HPV-related
cancers in women with LP, probably due to HPV reactivation or
predisposition to acquire new HPV infection, which eventually can
originate HSIL.4,5
There is an association between LP and cancer in the upper
gastrointestinal tract neoplasia (oral cavity, tongue,
esophagus).7 However, the risk of VSCC in women with
vulvar LP is still controversial. There are studies describing an
incidence of VSCC two times higher in women with vulvar LP7,8, while another study focusing on HPV-independent
vulvar cancer did not find any evidence of hypertrophic, classic or
erosive LP in VSCC specimens.2 Importantly, in one
study that associated LP to VSCC, the disease tended to be more
aggressive when vulvar LP was present (higher rate of regional lymph
node metastases at presentation and a rate of local recurrence of
40%).8
In face of contradictory evidence when revisiting VSCC and LP, our study
aimed to analyze a series of women with vulvar LP followed during an 11
years period, to assess the risk of developing preinvasive and invasive
vulvar lesions.