Results
A total of 308 patients were included in the study, comprising 178 (58%) OWs and 130 (42%) IWs. Table 1 summarizes the characteristics of each cohort with the statistical outcomes.
The mean age (SD) of the OWs was significantly higher than the IWs (75.17 [10.74] vs 69.73 [9.98] years; P<.001). The sex distribution among the 2 cohorts was significantly different (P=.002); the OW group featured a slightly higher proportion of men than women (92 [52%] vs 86 [48%]), whereas women were clearly more prevalent in the IW group than men (85 [65%] vs 45 [35%]).
No significant differences regarding eye color (blue/gray vs brown/black) between the 2 cohorts were found (P>.05). In the same way, the 2 cohorts did not show differences in the natural hair color (red/blonde vs brown/black)(P>.05).
Fitzpatrick skin type II was the most common between both cohorts (82 [46%] OWs and 75 [58%] IWs), but no statistical differences regarding the proportions of each skin type were found (P>.05).
History of sunburns (>2 episodes) was significantly different between the 2 cohorts. The incidence of second-degree sunburns in childhood was higher in IWs (P<.00001), while the incidence of second-degree sunburns in adulthood was higher in OWs (P=.002).
Most OWs had a positive family history of BCC (101 [57%]), while the majority of IWs had a negative family history of BCC (90 [69%]). This difference was statistically significant (P=.03).
Table 2 shows the distribution of anatomic sites of BCCs in OWs and IWs. The nose was the most frequently affected area in OWs (35 cases [20%]), while the cheek was the most common location (23 [18%]) in IWs. Comparison of the frequency of BCC incidence for each anatomic location revealed that only the rate for truncal BCC was significantly different; IWs had a higher incidence of truncal BCCs than OWs (P=.0035). Although the differences between groups were not statistically significant, there was a trend toward a higher incidence of BCCs on the forehead in OW (P=.06).
In both cohorts, the most prevalent histologic subtype was nodular BCC (133 [75%] OWs and 88 [68%] IWs), followed by superficial BCC (17 [10%] OWs and 27 [21%] IWs). The incidence rate of nodular BCCs was statistically different between the 2 cohorts, with OWs showing a higher incidence compared to IWs (P=.024). Regarding the superficial subtype, the opposite was observed: IWs had significantly increased risk compared to OWs (P=.05). There was a trend toward a higher incidence of morpheic BCCs in OWs than IWs, but the difference was not statistically significant (P=.07).
