Skin cancer: Genetics, immunology, treatments, and psychological care

Non-melanoma skin cancer (NMSC), consisting of basal cell carcinoma and squamous cell carcinoma, is considered the most common form of malignancy in humans. Melanoma is another major skin cancer, accounting for a small percentage of skin cancers, but is the deadliest form of skin cancer. Several players contribute in the pathogenesis of skin cancers, including genetics and epigenetics, various types of immune cells, and environmental risk factors. During recent years, some novel genes, numerous new therapeutic options, and also some new approved drugs associated with skin cancer have been introduced in the literature. Moreover, psychological care, which might be underestimated and remains unmet in case of many patients, is being emphasized of late. Considering the fact that skin cancer is a multifactorial condition that could be developed or influenced by genetic alterations, immune system alterations, and also environmental and lifestyle changes, it needs to be discussed from different points of view. In this chapter, all the mentioned factors were discussed both in case of NMSC and melanoma. After giving a clinical insight, risk factors, clinical manifestations, and the pathology of these conditions, recognized mutated genes as well as rare syndromes associated with NMSCs and melanoma have been discussed. Additionally, epigenetic factors (methylation, histone modifications, and microRNAs) have also been introduced. Since immune responses are the determinants of outcome, the role of the most studied immune cells in skin cancer patients such as T cells, natural killer cells, dendritic cells, macrophages, and mast cells have been discussed in detail. There is also some limited evidence of the contribution of autoimmune diseases and some viruses in the pathogenesis of skin cancer. Having an overview of the signaling pathways involved in skin cancer development and several clinical trials has led to the approval of some drugs belonging to various treatment strategies, including targeted therapy, immunotherapy, and the oncolytic viruses. These treatments seem to be potent enough to replace traditional non-surgical treatment options for skin cancer. Since patients with cancer not only need physical improvement but also psychological Interventions, the last section of this chapter covers the psychological issues in patients with skin cancer. Psychological outcomes, psychoneuroimmunology, and supportive cares for those who suffer from psychological problems are covered in this chapter.