Although it is very difficult to establish a correlation between the behavior of tumor cells in vitro and in vivo tumors, in this study we tried to analyze some functions of the tumor cells isolated from head and neck tumor fragments, comparatively with the tumor cell cultures, hoping that the results could help the clinician to choose optimal treatment for head and neck cancer patients. The aim of the present study was to evaluate the expression of p53 protein, the apoptosis process and the cell cycle parameters in the cell cultures of head and neck carcinoma obtained from fragments of tumor excised from patients. Using ELISA assay and flow cytometry methods we analyzed the p53 protein expression, distribution of the cell cycle phases and the level of apoptosis in the tumor cells which were immediately isolated from the tumor fragments, as well as in the ones that were subsequently passed in culture several times. Our results showed that p53 protein expression was weak in four (33.3%) patients, moderate in three (25%) patients and intense in five (41.6%) patients. Our data showed that both tumor cells isolated from the tumor fragments (passage 0), as well as cell cultures at passage 5 had the percentage of S-phase of the cellular cycle higher than 20%, suggesting that tumors have high proliferative activity. The tumor cells cultures have a small percentage of apoptosis that may reflect a biological aggressive tumor character. In conclusion, these data may improve the diagnostic protocols and help to an efficient monitoring of therapy.