The aim of this research is to decrease the number of inadequate tumor-free margins, probably resulting in less adjuvant therapy, less local recurrences and better quality of life.

Buccal mucosa cancer is a rare disease. In the Netherlands, approximately 100 patients are treated for this disease each year. To obtain good local control, it is important that the histological distance from the tumor to the resection plane is 5 mm or more (tumor-free margin). If the tumor-free margin is smaller, such as close (1-5 mm) or involved (<1 mm) margins, there is usually an indication for adjuvant therapy. Now, the tumor-free margins in buccal mucosa cancer are often insufficient, so that a significant proportion of patients require adjuvant treatment (re-resection or radiotherapy). Postoperative radiotherapy can greatly reduce the quality of life due to the development of, for example, osteoradionecrosis, mucositis and fibrosis. During a re-resection it is often difficult to find the location of the insufficient margin. Ultrasound-guided resection can be used to visualize the tumor during surgery, in order to improve the tumor-free margins. Currently, the tumor-free margin is only estimated palpably and frozen sections are sometimes used in case of doubt.

The aim of this research is to decrease the number of involved margins, probably resulting in less adjuvant therapy, less local recurrences, and better quality of life.

In this trial, 50 patients with a squamous cell carcinoma of the buccal mucosa will be included for treatment with ultrasound-guided resection.

50 patients with a squamous cell carcinoma of the buccal mucosa, who will be treated with surgery under general anesthesia, will be included in this study. The tumor has to be visible as an hypo-echogenic region on the ultrasound.

Inclusion Criteria:

• buccal mucosal squamous cell carcinoma
• surgical removal under general anesthesia

Exclusion Criteria:

• tumor is not visible on ultrasound as echolucent region