[Basal cell carcinoma of the skin--biological behaviour of the tumor and a review of the most important molecular predictors of disease progression in pathological practice].

Basal cell carcinoma of the skin is currently the most frequent malignancy in human population. Basal cell carcinoma represents a heterogeneous group of tumors with a variable clinical and morphological picture. Based on its biological behaviour, we generally differentiate between indolent (superficial and nodular) and aggressive type (infiltrative, micronodular, and metatypical) of basal cell carcinoma. Because of the different biological characteristics of these tumors, it is questionable whether they are a part of a continuous spectrum of carcinogenesis, starting with indolent and ending with aggressive forms, or they represent separate developmental lines. In the current clinical practice, there is an increasing demand for identification of tumors that are prognostically more adverse and their impact on the overall health status of patients is more serious. Recent advances in pathology and molecular medicine allow identification of various biomarkers from tumor tissue that are significantly involved in the mechanisms of malignant cell transformation. Detection of these biomarkers is of great importance in predicting further clinical behaviour of the cancer. The authors of the paper present basic information about biological behaviour of cutaneous basal cell carcinoma and provide an overview of the most important biomarkers that influence the clinical outcome and disease progression and are detectable through a routine biopsy tissue examination. It is now necessary to search for novel histological and molecular parameters that, in the future, could have a prognostic value in diagnostic and therapeutic process of this disorder.