Objectives: Prostate cancer is the most frequently diagnosed cancer in elderly men, and it is the second cause of death in man today. As well as in other tumors, biomarkers useful in the early detection and diagnosis of prostate cancer, prognosis and therapy, or in determining molecular ways of carcinogenesis are intensively examined. Pre-operative serum PSA, pathological grade according to Gleason, positive surgical margins (with and without extraprostatic extension) and capsular incision are significant in predicting clinical and biochemical recurrence of the disease. However, a real prognostic importance of positive margins should still be defined. In prostate carcinomas, MMP-2 and MMP-9 are molecular biomarkers which indicate their invasive and metastatic potential. Changes in the expression and function of adhesion molecules, as for example CD44s, correlate with a progression of malignant tumors. CD44s recruits and accumulates MMP-9 on the cell membrane, enabling this kinaze to stimulate indirectly angiogenesis and invasion. CD44s is also recognized as a marker of parent tumor cells playing, in early metastasis a significant role in the renewal of the cells, preparation of pre-metastatic, epithelic-mesenchimal transition and resistance to apoptosis. Understanding a different expression of CD44s marks and metalloproteinasis in the field of invasion may help in recognizing patients with more aggressive forms of prostate tumors who should be treated surgically and also additionally.The aim of this study was the identification of a mutual connection of biomarkers, as the patients age, PSA, Gleason score, the stage of the disease in patients treated by radical prostatectomy and the influence of these biomarkers on the biochemical recurrence of the disease in prostatectomy patients, and comparing groups of patients with positive as well as those with negative resection margins. The aim was also to determine and compare tissue expression of metalloproteinasis-2 and -9 and CD44s markers in the main tumor mass and the tumor on the positive margin, and comparing this expression with the mentioned clinic pathological parameters. Patients, material and methods: The study is retrospective and it covers the period from 2000 to 2006. From the files of the medical documentation of the Clinic of urology of the Clinical Hospital Center Rijeka, 121 patients with acinous type of prostate adenocarcinoma were chosen and adequate clinical data were collected. From the files of the Department of Pathology of the School of medicine in Rijeka, tumor material was taken from chosen patients received by radical prostatectomy. Tissue expression of metalloproteinesis-2 and -9 and CD44s marks and a proliferative marker Ki67 were identified by immunohistochemic standard Avidin-Biotin immunoperoksidose technique on tissue microareas (TMA). The expression of MMP and CD44s was evaluated semiquantitively, taking into consideration the percentage and intensity of tumor cells coloring. The obtained data were analyzed using statistical methods and then compared with more recent world literature. Results: The age of the patient was not in correlation with other pathohistologic parameters and so neither in correlation with the expression of molecular markers. Also, not a single pathologic parameter was isolated as a useful and significant diagnostic tool. By analyzing an average score and comparing groups with a positive and negative margin, a significantly larger Gleason score was found in groups with a positive margin (p=0.0032), while PSA in both groups is not significantly different. A significant difference among groups exists only in frequencies of stages pT2A, pT3A and pT3B. MMP-2 and -9 coloring in tumor cells are cytoplasmic and varied in the intensity and percentage, and we did not find negative tumors. Increased expression of MMP-2 was found in tumors of poor differentiation and higher Gleason sum. MMP-2 expression at the edges was significantly higher than the expression in the main tumor mass (p=0,0301). MMP-9 shows a notably higher expression in a group of tumors with a positive group resection edge (p=0,0121). Tumors larger than 1 cm. (p=0,038) and elevated expression were significantly assiociated with biochemical recurrence in the group of patients with tumors of a negative edge of the resection (p=0,0207). CD44s shows a loss of expression of molecules on tumors cells with increased Gleason sum of discontinuous membrane staining and focal irregular distribution in the sample. CD44s and MMP-9 together are inversely dependent biomarkers (p=0,0185). Ki67 proliferation index was significantly increased in tumors in the group of patients with biochemical reccurence (p=0,01272). Conclusion: This study confirmed the influence and prognostic significance of the investigated biomarkers in prostate carcinomas in patients treated by a radical prostatectomy, especially in a tumor group with a positive margin of surgical resection which presents a problem in the choice of a postoperative treatment of the patient.