In our study, the prevalence of keratinocytes skin cancers was 11.8%, lower than the 26% reported in Brazil [8], 25% in Tanzania [11], 23% in South Africa [12] and 20,98% in Nigeria [13], but higher than the 4.6% reported in France [14]. The reason for our low rate would be that other PWA in more remote areas, which do not even have access to health care centres, have not been affected by these activities. While the mobile consultation strategy is the one we have used in the campaigns, the majority of our consultations are limited to urban PWA. Moreover, PWA are the target of prejudice and social exclusion and have limited access to specialized medical care and resources [8, 15].
The average age of keratinocytes skin carcinomas onset among the PWA in this study was 38.6 years, much lower than that of the general Togolese population (42 years) [10]. However, it is similar to the 35.5 years found in Tanzania [6] with an earlier onset of BCC (median age 35.5 years) compared to SCC (median age 39 years). PWA develop sun damage earlier due to lack of sun protection (covering clothes, wide-brimmed hats, sunscreen, indoor occupations to avoid repeated sun exposure), so malignant tumours occur from the second decade of life [2, 6].
We have identified 54 cases of keratinocytes skin carcinomas dominated by BCC (57.4%), with some patients having multiple cases and types. This finding of multiple lesions has already been made in the literature in this population [8, 9, 16, 17], including 14% (4 cases) of combined BCC and SCC in Brazil [8], one case of multiple BCC in India [16] and one case of SCC, Bowen's disease in Japan [17]. In our study, there was a predominance of BCC with a BCC/SCC ratio of 1.47. This predominance could be explained by the fact that in our country, it is the dermatologist who goes to the PWA, allowing us to detect mild cases. As in our study in Nigeria [13], malignant skin lesions comprising 55% of BCCs, 22% of SCCs, 18% basosquamous carcinoma and 5% collision tumour (BCC and SCC). In Brazil [8], it was 62% BCC, 51% SCC and 7% melanoma. These three studies including ours, are cross sectional community based studies. However, most African studies, all retrospective hospital based, show that SCC is the most common cancer in this population [4, 6, 9, 18]. In Tanzania, there were 72 cases (53.7%) of SCC versus 61 (45.5%) of BCC and one case of melanoma (0.75%) [6]. In another study in Nigeria, there were 68.2% SCC, 22.7% BCC and 9.1% melanoma [9]. A review had shown that BCC was observed in 5–88% of cases compared to 9–23% and 1.3-3% respectively for BCC and melanoma [19]. Indeed, the incidence of SCC doubles with every 8–10 degrees of decline in latitude with a maximum incidence at the equator [6]. Finally, melanoma is rare in PWA with a similar incidence in the general population [8], a tumour that we did not find in our study.
Skin cancers develop at sites in the body exposed to ultraviolet radiation [4, 18, 20]. In our study, the lesions were mainly located in the cephalic region (33 cases; 61.1%), followed by the upper limbs (15 cases; 27.8%). The cephalic region and the neck are similar locations reported in other studies [13, 20, 21]. Female resellers (21.2%), traders (15.2%) and farmers (12.2%) were the predominant occupations in our study. In Nigeria [9], these were artisans and farmers. These activities chronically expose the head and neck to the sunlight, which is the major risk factor for skin cancer [5, 20].
Limitations Of Study
The main limitation of this study is that the two campaigns concerned only 10 towns in Togo, without forgetting that rural areas were not concerned. Although awareness campaigns and statements have been advertised to invite PWA to these campaigns, the number of PWA reached by these activities is far below the estimates of the number of PWAs in Togo according to the National Association of Albinos in Togo (ANAT). This fact partly explains the low rate of 11.8% of PWA diagnosed with skin carcinomas.