The two most common types of skin cancer are basal cell and squamous cell carcinoma, well known as nonmelanoma skin cancers. These cancers are the most common malignant tumors in white population and its incidence is increasing
dramatically. Information about the time of occurrence and cancer growth rate is a significant segment in establishing the primary skin cancer diagnosis. The aim of this prospective study is to determine the correlation between the size of basocellular and squamous cell carcinoma, represented through the function of cancer diameter and time period elapsed from their occurrence up to the surgical intervention. Apart from general anamnestic data, it was also insisted on as precise as possible datum referring to the cancer occurrence time. All cancers have been hystopathologically confirmed. Linear regressive analysis was used for establishing the interdependence between the diameters of tumors and their duration. The average growth of basocellular carcinoma in our patients was 4.3 mm on annual basis, i.e. 6.1 mm annually for squamous cell carcinoma. Tumor duration is a significant anamnestic datum for establishing diagnosis which can indicate a biological aggressiveness or skin cancer type.