A phase II study of sorafenib in recurrent and/or metastatic salivary gland carcinomas: Translational analyses and clinical impact.

BACKGROUND: Pre-clinical and clinical evidence suggests a rationale for the use of anti-angiogenic agents, including sorafenib, in recurrent and/or metastatic salivary gland carcinomas (RMSGCs). This study evaluates the activity of sorafenib in patients with RMSGCs and also investigates whether the activity of sorafenib could be related to its main tailored targets (i.e. BRAF, vascular endothelial growth factor receptor 2 [VEGFR2], platelet-derived growth factor receptor α [PDGFRα] and ß, RET, KIT). PATIENTS AND METHODS: Patients received sorafenib at 400 mg BID. The primary end-point was response rate (RR) including complete response or partial response (PR); secondary end-points included RR according to Choi criteria, disease control rate (DCR), overall survival (OS), and progression-free survival (PFS). RESULTS: Thirty-seven patients (19 adenoid cystic cancers, ACC) were enrolled. Six PRs were recorded. RR was 16% (95% confidence interval [CI]: 6-32; 11% in ACC and 22% in non-ACC). Choi criteria could be applied in 30 out of 37 cases with a RR of 50% (95% CI: 31-69%); DCR was 76% (95% CI: 59-88%). Incidence of ≥G3 adverse events was 29.7%. Median PFS and OS for the entire population were 5.9 months and 23.4 months, respectively. Median PFS and OS were 8.9 and 26.4 months for ACC versus 4.2 and 12.3 months for non-ACC patients. All the cases showed expression of PDGFRß in the stroma and VEGFR2 in endothelial cells; PDGFRα positivity was found in the stroma of four (27%) cases. All except for two cases showed no PDGFRß, VEGFR2 and PDGFRα expression in the tumour cells. KIT expression was restricted to ACC and a weak RET expression was limited to one adenocarcinoma, not otherwise specified (NOS). No BRAF mutation was found. No correlation was observed between the sorafenib activity and the expression of its markers although all six responders (two ACC, one adenocarcinoma, NOS, one salivary duct cancer [SDC], one high-grade mucoepidermoid [HG-MEC] and one poorly-differentiated cancer) are enriched in the stromal component showing a PDGFRß immunodecoration. In ACCs, immunohistochemistry revealed MYB protein expression in 15/16 cases (94%) and the MYB-NFIB fusion oncogene was observed in 9/14 (64%). CONCLUSIONS: Sorafenib is the first anti-angiogenic agent to demonstrate activity in RMSGC patients, particularly in some histotypes such as HG-MEC, SDC and adenocarcinoma, NOS. The PDGFRß-positive rich stromal component characterising these histotypes and the lack of correlation between the activity of sorafenib and its targets suggests anti-angiogenic effect as the prevalent mechanism of action of sorafenib in SGCs.

Decreased occurrence of osteonecrosis of the jaw after implementation of dental preventive measures in solid tumour patients with bone metastases treated with bisphosphonates. The experience of the National Cancer Institute of Milan.

BACKGROUND: Screening of the oral cavity and dental care was suggested as mandatory preventive measures of osteonecrosis of the jaw (ONJ) in patients receiving bisphosphonates (BPs). We investigated the occurrence of ONJ before and after implementation of dental preventive measures when starting BP therapy. PATIENTS AND METHODS: Since April 2005, 154 consecutive patients treated with BPs (POST-Group) have undergone a baseline mouth assessment (dental visit +/- orthopantomography of the jaws) to detect potential dental conditions and dental care if required. A retrospective review was also conducted of all consecutive cancer patients with bone metastases (PRE-Group) and treated for the first time with BPs from January 1999 to April 2005 in our clinic without receiving any preventive measure. Incidence proportion and incidence rate (IR) were used to estimate the incidence of ONJ. RESULTS: Among the study population (966 patients; male/female=179/787), 73% had breast cancer. 25% of patients were given zoledronic acid (ZOL), 62% pamidronate (PAM), 8% PAM followed by ZOL and 5% clodronate. ONJ was observed in 28 patients (2.9%); we observed a reduction in the incidence of ONJ from 3.2% to 1.3%, when comparing-pre and post-implementation of preventive measures programme. Considering the patients exposed to ZOL, the performance of a dental examination and the application of preventive measures led to a sustained reduction in ONJ IR (7.8% in the PRE-Group versus 1.7% in the POST-Group; P=0.016), with an IR ratio of 0.30 (95% confidence interval 0.03-1.26). CONCLUSIONS: ONJ is a manageable and preventable condition. Our data confirm that the application of preventive measures can significantly reduce the incidence of ONJ in cancer patients receiving BPs therapy. Dental exams combined to the identification of patients at risk in cooperation with the Dental Team can improve outcomes and increase the number of ONJ-free patients.