Histopathological study of perilesional skin in patients diagnosed with nonmelanoma skin cancer.

Abstract

Epidemiological and clinical data suggest that actinic damage to the skin is an important predictor of skin carcinogenesis. To investigate the association of squamous cell carcinoma (SCC) and basal cell carcinoma (BCC) with sun-damage alterations seen by histopathology. In the current prospective study, perilesional skin of SCC or BCC lesions was evaluated for presence of alterations associated with chronic photodamage. Presence of scarring, perineural/perivascular invasion, haemorrhage/haemorrhagic crust, ulceration/erosion and margin involvement were also assessed. Of 6038 included lesions, 4523 (74.9%) were BCCs and 1515 (25.1%) were SCCs. Presence of actinic damage was five times more frequent in SCC than in BCC (OR=5.29, 95% CI 4.44-6.00, P<0.001), and diagnosis of SCC was twice as common in photo-exposed than nonphoto-exposed body sites (OR=2.34, 95% CI 2.03-2.70, P<0.001). There were twofold higher odds for actinic damage in SCC compared with Bowen disease (OR=2.015, 95% CI 1.55-2.61, P<0.001). Assessing the different BCC histological subtypes, we found that nodular BCC had at least twofold higher odds (OR=2.63, 95% CI 2.09-3.32), infiltrative BCC had 48% higher odds (OR=1.487, 95% CI 1.18-1.87) and basosquamous BCC had fourfold higher odds (OR=4.10, 95% CI 3.01-5.57) of having actinic damage compared with superficial BCC. Histological verification of ultraviolet-associated alterations in the perilesional skin in patients with NMSC in our study confirms the aetiopathogenic link between sun exposure and epithelial carcinogenesis on a histopathological basis. This correlation was stronger for SCCs than for BCCs.