Clinicopathological and virological characteristics of superficially invasive squamous-cell carcinoma of the anus

Aim The clinicopathological and virological characteristics of anal superficially invasive squamous-cell carcinoma (SISCCA) were determined. Method Seventeen patients with a completely excised stage T1N0M0 anal squamous-cell carcinoma (SCC) were included in the study. The tumours were divided into superficially invasive and invasive. Patients with anal high-grade squamous intraepithelial dysplasia, which corresponded to anal intraepithelial neoplasia (AIN) Grades 2 or 3, were used as a control group. Clinicopathological and virological characteristics were investigated. Overall survival and cancer recurrence-free survival were also assessed. Results Of the 17 patients, 12 (70.5%) were men. Ten (58.8%) were human immunodeficiency virus positive. Seven (41%) patients met the same diagnostic criteria as those recently proposed for anal SISCCA. According to the results obtained using the polymerase chain reaction, human papillomavirus (HPV) 16 was the most commonly detected (94%) type of HPV. Twelve (70.6%) patients with an inadequate surgical margin around the tumour received adjuvant radiotherapy, including the two (11.7%) tumours that locally recurred, one of which was an anal SISCCA. Superficially invasive anal cancers differed from the other T1N0M0 anal carcinomas according to the clinical presentation and the absence of lymph-vascular invasion (LVI). There were no differences in cancer recurrence-free and overall survival rates between the superficially invasive and invasive groups. Conclusion Anal SISCCAs have a low index of clinical suspicion, are associated with an absence of LVI and are linked to high-risk HPV. Prospective studies are needed to define the clinical behaviour of these anal tumours and to determine their best therapeutic strategy.