OP086: Buccal cancer involving masticator space: Classification and outcome after radical (compartment) resection

Purpose Buccal-cancer involving masticator-space (T4b) is a difficult problem. This study proposes classification for these tumors based on clinical-radiological-pathological findings and demonstrates outcome with radical resection. Material and methods Total 45 patients with T4b were included in this study. All patients underwent composite-resection with enbloc removal of contents in masticator space (compartment surgery). All resected specimens were pathologically evaluated for involvement of various structures (mandible, maxilla, pterygoid muscles and plates, masseter muscle) and extent of their involvement. These results were compared to clinical–radiological findings to classify patients in three categories. Category I: Mild trismus, medial pterygoid involvement (infra-sigmoid notch). Category II: Moderate-severe trismus, medial–lateral pterygoid muscle involvement with/without involvement of plates (Supra-sigmoid notch). Category III: Severe trismus, involvement of pterygo-maxillary fissure and possible intracranial extension. Results 45 patients with advanced buccal-cancer (T4b) were included in study. Skin and mandible were involved in 30 and 24 cases respectively while pterygoid-muscles in 34 cases and masseter-muscle in 32 cases. Lymphnodes were involved in 17 cases and only one lymphnode was positive in 12 instances. Average distance for soft tissue margins at depth was 2 cm. Margin was positive in three cases. Pterygomaxillary fissure margin was positive in two cases. Total 23 patients were classified in category I while 15 patients were classified in category II. Seven patients were classified in category III according to comparative findings. At 24 months median follow-up (13 to 35 months), 38 patients were alive without disease while two patients in category III developed local recurrence at skull base and intracranial level. No other patients developed local recurrence. Conclusion T4b buccal cancer has extensive soft tissue involvement in masticator space. Radical (compartment) surgery has potential to provide good margin and local control and early results good outcome for tumors contained within masticator space (categories I and II). Patients classified in category III with pterygomaxillary fissure involvement may need combined approach.