Impact of stratified resection margin classification on local tumor control and survival in patients with oral squamous cell carcinoma.

BACKGROUND: Guidelines recommended for resection of oral cancer define a free margin of ≥5 mm as clear and safe (R0). This statement was questioned recently based on the assumption that different surgical margins may hold different risk categories. The aim of this study was to investigate the impact of stratification of the surgical margins on the survival outcome of patients with oral cancer. METHODS: In a cohort of 753 patients, the hazard ratio for local recurrence-free survival (LRFS), overall survival (OS), and oral cancer-specific survival (OCSS) were estimated for R0 resection, the close margin of 1-4 mm, involved resection borders but with free frozen sections. Competing risk factors were considered in the statistical regression model. RESULTS: One hundred seventy-three (23%) patients developed local recurrence and 316 (42%) died in the 5 follow-up years. There was a gradual improvement in the LRFS, OCSS, OS with the increase of clear margin. OS showed a similar tendency. CONCLUSION: Not all patients with an R0cm status carry the same risk for impaired LRFS, OCSS, and OS. Their risk to develop recurrence is higher than those patients with R0 ≥5 mm but stratified risk management can be recommended according to the presented results.

Impact of Zoledronic Acid and Denosumab Treatment on Growth Factor Concentration in Platelet Rich Fibrin of Patients With Osteolytic Bone Metastases.

BACKGROUND/AIM: Side effects of zolendronic acid (ZA) and RANKL inhibitors (RANKL-I) include impaired wound healing and osteonecrosis of the jaw. Platelet rich fibrin (PRF) enhances wound healing and bone remodelling in vivo and in vitro. However, the topical use PRF in the surgical treatment of patients with medicament-related osteonecrosis of the jaw is relatively new and not thoroughly investigated. Furthermore, the potential attenuation of the PRF effect following antiresorptive treatment remains unclear. Therefore, we investigated the concentration of growth factors within the PRF in healthy volunteers and in patients with antiresorptive treatment. PATIENTS AND METHODS: Blood samples from healthy volunteers and patients were used to produce PRF. The levels of EGF, VEGF, PDGF-BB, TGF-ß1, BMP-2, and CD31 in the PRF was investigated by ELISA. RESULTS: ZA treatment induced a significant decrease in EGF and TGF-ß1 levels, whereas RANKL-I caused lower TGF-ß1 levels. CONCLUSION: Reduced EGF levels in PRF after ZA treatment may explain the delayed wound healing and question the positive effect of PRF in these patients. PRF use in patients undergoing RANKL-I treatment seems to be more justified.