###### Abstract  
The incidence and prevalence of skin cancers is currently increasing worldwide, with early detection, adequate treatment, and prevention of recurrences being topics of great interest for researchers nowadays. Although tumor biopsy remains the gold standard of diagnosis, this technique cannot be performed in a significant proportion of cases, so that the use of alternative methods with high sensitivity and specificity is becoming increasingly desirable. In this context, liquid biopsy appears to be a feasible solution for the study of cellular and molecular markers relevant to different types of skin cancers. Circulating tumor cells are just one of the components of interest obtained from performing liquid biopsy, and their study by complementary methods, such as dielectrophoresis, could bring additional benefits in terms of characterizing skin tumors and subsequently applying personalized therapy. One purpose of this review is to demonstrate the utility of liquid biopsy primarily in monitoring the most common types of skin tumors: basal cell carcinoma, squamous cell carcinoma, and malign melanoma. In addition, the originality of the article is based on the detailed presentation of the dielectrophoretic analysis method of the most important elements obtained from liquid biopsy, with direct impact on the clinical and therapeutic approach of skin tumors. can cause significant morbidity due to its destructive local spread [8]. High prevalence together with the accessibility of skin examination have allowed researchers to obtain detailed information about BCC's pathogenesis, clinical presentation, and histopathology. The complexity of the disease is noticed when trying to summarize its pathogenesis, with several environmental (UV radiation, UV-sensitive phenotype) and genetic risk factors (genetic polymorphisms) coming into interplay [9]. Additionally, BCC heterogeneous histological classification, its immunohistochemical and genetic profile bring relevant [10], however frequently incomplete, data for the therapeutic approach. Squamous cell carcinoma (SCC), the second most frequent cancer in humans, accounts for the majority of the remaining cases of NMSC [11]. In trend with the enhanced incidence and prevalence of BCC, epidemiological data on SCC estimates a doubling of its incidence in European countries by 2030 [12]. Although SCC usually exhibits a benign clinical behavior, it can be locally invasive and have a significantly higher risk of metastasis compared to BCC, caring in that case poor survival prognosis [13]. SCC arises from dysplastic epidermal keratinocytes, the malignant proliferation being sustained by several risk factors, including immunosuppression, previous history of actinic keratosis (AK), and chronic sun exposure [14]. Both BCC and SCC have been intensively studied in recent years, and a huge amount of new data related to pathogenesis and treatment is emerging. Although still incompletely elucidated, the underlying mechanism of the neoplastic process is better understood nowadays thanks also to a better knowledge of the molecular and genetic factors involved [15]. Subsequently, a fast development within the therapeutic field can also be observed, in addition to surgical intervention, with the emergence in current clinical practice of new agents that inactivate key molecules in the malignant process. PTCH1 drug efflux antagonist [16] and Smoothened (SMO) inhibitors [17] used in BCC therapy, together with Anti-EGFR agents [18] and Janus kinase (JAK) inhibitors suited for SCC pharmacological treatment are just a couple of examples of currently available drugs in the NMSC therapeutic approach. Malign melanoma (MM), one of the most aggressive cancers in humans, is becoming one of the most common malignancies worldwide [19]. Recording a continuous increase in incidence, MM is the cause of more than 90% of skin-disease-related deaths [20].