Stress denotes a real or perceived perturbation to an organism’s physiological homeostasis or psychological well-being [11]. The American Psychological Association states some stress can be beneficial at times, producing a boost that provides the drive and energy to help people get through situations like exams or work deadlines. However, they emphasize that an extreme amount of stress can have health consequences and adversely affect the cardiovascular, immune, neuroendocrine and central nervous systems [12]. So stress can lead to psychological and physical health issues.

Chronic stress is defined as stress that persists for several hours, days, weeks, months or years and it has been shown to have immunosuppressive effects that causes suppression of skin cell mediated immunity [13].

Ultraviolet radiation is considered a “complete carcinogen” due its mutagen and non-specific damaging agent properties. It is a tumor initiator and tumor promoter [14]. The ultraviolet B radiation causes DNA damage, epidermal hyperplasia, inflammation, and subsequent tumor development [15].

Saul et al. performed a study to test the hypothesis that chronic stress could accelerates the emergence and progression of UVB induced squamous cell carcinoma and as well that it could inhibit the regression of this type of cancer. The researchers examined the effects of chronic stress on the emergence, progression, and regression of squamous cell carcinoma induced by low level exposure to UVB radiation in a mouse model and they found that chronic stress suppresses Type 1 cytokines and protective T cells and increases regulatory/suppressor T cell numbers. These events increased susceptibility to UV-induced squamous cell carcinoma in this mouse model. They also explained that because squamous cell carcinoma and basal cell carcinoma are immunogenic non-melanoma skin cancers, these findings could also be applicable to basal cell carcinoma [13].

In contrast to chronic stress that suppresses immunological function, acute or short-term fight-or-flight stress response experienced during immune activation can enhance innate and adaptive immunity. Dhabhar and colleagues performed a study to evaluate effects of short-term stress on cellular immunity and resistance to squamous cell carcinoma. The authors compared a control group and a short-term stress group of mice’s. They were treated identically except that the short-term stress group was restrained (2.5 h) before each of nine UV-exposure sessions during weeks 4–6 of the 10-week UV-exposure protocol. Tumors were measured weekly, and tissue collected at weeks 7, 20 and 32. Compared to controls, the short-term stress group showed that activation of short-term stress physiology increased chemokine expression and T cell trafficking and/or function during/following UV exposure, and enhanced Type 1 cytokine-driven cell-mediated immunity that is crucial for resistance to SCC. This research suggests that short-term stress has adjuvant-like immuno-enhancing effects that may provide a novel mechanism for enhancing immune system mediated tumor-detection and elimination [16].

Higher levels of anxiety can also increase the progression of squamous cell carcinoma. Another study performed by Dhabhar and colleagues found that high-anxious, stress-prone behavioral phenotype resulted in a higher chronic stress burden, lower protective-immunity, and increased progression of this immuno-responsive type of skin cancer. These researchers found that the deleterious effects of high trait anxiety could be: exacerbated by life-stressors, accentuated by the stress of cancer diagnosis/treatment, and also mediate increased tumor progression and/or metastasis. The use of anxiolytic medications after the diagnosis and during the treatment could improve the disease outcome [17].

Stressful events during childhood may predispose an individual to developing basal cell carcinoma. Child emotional maltreatment can result in lasting immune dysregulation that may be heightened in the context of more recent life stress. Fagundes et al. investigated 91 patients with diagnosis of BCC and found that maternal and paternal emotional maltreatment during childhood interacted with the occurrence of severe life events and predicted the local immune response to the tumor. The authors also found that the immunoreactivity observed in BCCs and the surrounding stroma reflected an anti–tumor-specific immune response that can be altered by stress [18].

Oxidative stress is defined as a disturbance in the balance between the production of reactive oxygen species (free radicals) and antioxidant defenses [19]. Normal cell function includes the free radical production that occurs in all cells of the body. Excess free radical production originating from exogenous or endogenous sources contributes to development of many diseases including skin cancers [20]. An increased amount of oxidants causes chronic inflammation, collagen fragmentation and disruption in skin cell functions causing skin cancer. Oxidative stress also participates of carcinogenesis process [21]. Sander and colleagues explains that melanoma cells presents increased oxidative stress. This could cause tissue damage and lead to metastasis. While in non-melanoma skin cancer, the reduction of the antioxidants defense caused by chronic UV exposure contributes to the complex and multistep carcinogenesis [22].

Antioxidants functions include lowering oxidative stress, DNA damage, and malignant transformation. They attenuate the damaging effects of ROS and impair and/or reverse many of the events that contribute to epidermal toxicity and disease and can lower the incidence of certain types of cancer such as skin cancers [23, 24]. Different types of oral or topical exogenous antioxidants have been studied as adjuvants to skin cancer prevention [25]. Some examples include β-carotene, vitamin C, vitamin E, caffeine, retinoids, green tea, glutathione and silymarin [24, 25].

The emotional stress of receiving the diagnosis of skin cancer, the fear of recurrence and treatment implications can create new or worsen preexisting psychological stress [26].

Melanoma is the leading cause of death from skin diseases. França et al. explains that the possibility of recurrence, metastasis, and mortality levels related to this type of skin cancer is responsible for psychological distress [27]. Approximately 30 % of all patients diagnosed with this type of cancer report levels of psychological distress indicative of the need for clinical intervention. Risk factors for distress include younger age, female sex, lower education, visibility of affected body site, lack of social support, and negative appraisal of melanoma [28].

The emotional impact of melanoma can be profound and long lasting and severely impact patients and family members quality of life [29]. Baesley et al. performed a study with 386 patients and found that 32 % had anxiety and 15 % had depression. Forty-six percent of patients reported unmet needs. The three highest needs were for help with fears about cancer spreading (17 %), information about risk of recurrence (17 %) and outcomes when spread occurred (16 %). These authors emphasize the need to provide further melanoma specific information and better support with psychological concerns [30]. Erim et al. investigated anxiety, posttraumatic stress, and fear of cancer progression in a group of 70 patients with malignant melanoma who attended cancer aftercare. These patients were surveyed using the psychometric instruments Hospital Anxiety and Depression Scale (HADS), Posttraumatic Symptom Scale (PTSS-10), and Fear of Progression Questionnaire (FoP-Q). The researchers reported that the scores for the three anxiety parameters were low, but 7 % of the patients presented an increased HADS score, and 17 % an increased PTSS-10 value. These patients should receive the support indicated for their specific distress. Another finding in this study was that patients feared physical disabilities more than mental distress or lack of social support [31].

Dermatologists must be trained to identify patient’s needs and to screen the one’s that need further psychological support [32]. Patients who are younger, with lower educational levels, distressed and socially isolated are part of group risk for developing more psychological problems [33]. Anxiety and depression symptoms may persist many years after the treatment of melanoma. According to Beutel et al. patients may continue experiencing distress and reduced quality of life predicted by fear of recurrence, lack of social support, pessimism and self- blame [34].