e15021 Background: Sunitinib is a standard of care for first-line treatment of advanced or metastatic RCC. Recently, the association of sunitinib and bisphosphonates has been described to increase osteonecrosis of the jaw (Bozas and al, Oncologie 2010). We measured the potential impact of sunitinib on buccodental toxicities. Methods: Between Oct and Dec 2010, 58 patients with metastatic RCC treated by sunitinib (S) and 52 patients treated by chemotherapy (C) agreed to fill a self administered questionnaire assessing buccodental status included varying oral hygiene/care practices, history of bisphosphonate treatment, occurence of dental or gingival pathologies during treatment, and quality of life. T-tests and Chi-square analyses were used to compare differences between the two groups. Results: Median age of the 110 pts analyzed was 62,5 years (28-84) with majority of male in group S (73%) and female in group C (67%). Smokers were more represented in group C (23.1%) than in group S (8.6%) (p = 0.036). Among 58 pts in the group S, 9 had previously received bevacizumab, and 5 Sorafenib. Among 52 pts in the group C, 13 received an adjuvant chemotherapy, 39 had metastatic chemotherapy line, and 8 combination of chemotherapy and bevacizumab. Some pts in each group received bisphosphonates: 8 in group S (13.8%) and 4 in group C (7.7%) (p= 0.306). Higher frequencies of dental and gingival toxicities in group S were observed: pain (53.7% vs 46.3%, p= 0.007), teeth instability (43.1% vs 22.5%, p= 0.037), gingival bleeding (62% vs 42.4%, p= 0.010) and cavities (51.6% vs 25%, p= 0.005). Consequently, 62% (S) vs 42.3% (C) needed to change their alimentary habits (p= 0.010). Indeed, the pts of the group S had more frequently visited their dentist within the few months following treatment to remove pathological teeth (15 patients vs 4 patients, p= 0.013). Results were similar with or without bisphosphonate treated patients. Conclusions: Sunitinib seems to increase buccodental toxicity as compared to chemotherapy with or without bisphosphonate association. This work emphasizes the need of an optimal dental care and follow-up for patients treated with sunitinib.