Skin cancer is characterized by being a disease in which there is an abnormal growth of the cells of the skin tissues. Represents the most common cancer worldwide, exceeding the prevalence of other types of malignant neoplasms combined. It is classified in melanoma and non-melanoma skin cancer (NMSC), the latter encompassing keratinocyte carcinomas which can be subclassified into BCC and SCC. NMSC represents 99% of the total of skin neoplasms [24–26]. Most of the patients included in our study present BCC (70.2%), followed by SCC and with very few patients with mixed carcinoma and melanoma. This coincides with various registries that show that the prevalence is higher in BCC than in any other type of skin cancer [27, 28]. In addition, a higher percentage of skin cancer has been reported in men compared to women, with values ranging from 60 to 63% [29, 30]. In the study, a similar amount was presented in both genders; the differences may be influenced by the type of sampling and the number of patients included.
It has been previously reported that the incidence of NMSC increases with age, the probability of presenting BCC / SCC with each year of age increases up to 10%, while in melanoma only 4%, this could be since the older the immune system is less efficient in the resolution of some DNA damage [31]. Based on the results of the present study, it was identified that the mean age of patients with skin cancer is 66.5 years and that the age group with the highest percentage is 60–90 years. These results are like various studies carried out in a European population, with means of 63 years of age in patients with BCC and 64.7 years for patients with SCC [28, 29]. While the age range with the highest percentages has been described in patients with skin cancer is 61 to 70 years [32, 33].
Although, there are previous studies that refer to an occupation as a risk factor, finding a higher prevalence in the work of welders, specialized farmers, miners, and stonemasons in patients with BCC. While in those with SCC, occupations are to a greater extent than involved direct contact with livestock, construction workers, stationary motor operators, and bricklayers [28, 30]. Meanwhile, in our study, the highest percentage of patients reported being housewives. Other factors that could be influencing are the FST and the degree of solar exposure; The latter being one of the factors with the greatest impact on human skin and is particularly important in terms of sensitivity to UV-induced DNA damage [34, 35]. As in previous studies, the results of this study identified most of the participants with FST II and III. FST is one of the factors identified with the development of skin cancer, finding a higher prevalence in populations with light skin phototypes. In addition, it has been widely described that the location of skin cancer lesions is to a greater extent in photo-exposed areas such as the head, neck, cheeks, nose, etc. [32, 33]. These data agree with those found in the study population included, finding that 68.2% of skin cancers are in the head or neck region.
Regarding the results obtained for the personality dimensions. Taking into consideration the measures provided by the EPQ-R manual applied in healthy population for the different dimensions with means of 12.7 ± 4.0 for E, 13.4 ± 5.4 for N, 5.7 ± 3.5 for P, and 8.4 ± 3.8 for L. We observe similar values except for L, which is above the mean. However, this differential behavior may be due to the age of the subjects included, as is previously reported that L scores are higher in ages between 40 to 60 years. However, it is not the only dimension that has been associated with age, E is also associated even though it is inversely associated [36, 37].
The link between personality and cancer development has not yet been demonstrated, with conflicting results in different types of tumors. According to the results of some investigations where personality was evaluated in patients with lung, colon, breast, prostate, skin, leukemia, and lymphoma cancers, no associations were obtained regarding the risk of their development [20, 38]. However, there are reports of male patients with lung cancer presenting higher extraversion scores and lower neuroticism scores [39]. Others, for their part, have found in cancer survivors patients present higher levels of psychoticism and neuroticism with low levels of extraversion, although without significant differences [40]. Although the absence of a control group eliminates the possibility of inquiring about the possible connection between personality and the diagnosis of skin cancer in the subjects included. As in the studies mentioned above, our results reveal the influence of gender by obtaining higher values in the dimension of N in the female gender. The foregoing has been previously described in open populations, showing higher levels of N in women compared to men [41].
Environmental psychological factors such as mood states can modify and trigger an organic response [42, 43]. Personality relates to mood; some authors identify high scores in neuroticism associated with intense and long-lasting emotions of stress and therefore with the development of depressive behaviors [44]. It has been observed that cancer patients present comorbidities with psychological illnesses such as depressive disorder, even being considered as a risk factor for oncological development, leading to alterations both in the genesis and in the progression of the disease [3, 10, 45]. In addition, it has been documented that in older adults the presence of this disorder is associated with increased neuroticism in cancer survivors [46–48]. Similarly, in patients with BCC, a positive association with the presence of depression has been recorded [17]. Regarding the history of depression with the risk of melanoma skin cancer, it seems to present an association, especially in the female gender [16, 21]. Our results coincide with previous studies by identifying that more than a third of patients with skin cancer show anxiety/depressive symptoms. Also, we found that there is a significant relationship between depressive symptomatology scores and female gender. These results are highly relevant when knowing that depression is associated with just over half of the incidence of suicides, in addition to the fact that there are studies that mention a high prevalence of suicides in female patients with NMSC, it is commented that the deforming capacity of the disease as the main reason [27, 49].
Subsequently, we encounter that there are positive correlations between the scores for the anxious/depressive symptoms and the personality dimensions N and P. Something that has also been mentioned in previous studies where high levels of neuroticism can generate vulnerability to depressive symptoms. In addition, psychoticism has been shown as a predictor of depressive symptoms in breast cancer survivors [50, 51]. Furthermore, we observed positive correlations between the dimensions of N and P which have not been found in the reviewed literature. However, it has been identified that high levels of both N and P are related to negative coping responses to stress and suicidal ideation [37, 52, 53]. A negative correlation between anxiety/depression and the L dimension scores was also found, people with high L scores are related to the presence of psychiatric disorders such as depression and schizophrenia [36, 54].
Limitations of this study include its cross-sectional nature and the relatively small number of subjects studied. Therefore, we believe that further studies are required to confirm our results.