Oncological safety of harvesting local flaps from the neck in clinically node positive patients with oral squamous cell carcinoma.

Abstract

e18065 Background: Reconstruction of complex orofacial defects following tumour resection has always posed as a challenge for clinicians for providing functional and morphological outcomes. Though microvascular free flaps revolutionized reconstruction, local flaps provide a viable alternative in resource constraint settings. Oncological safety of harvesting local flaps has always been a matter of debate in oral squamous cell carcinoma due to proximity of nodal stations. Available literature on oncological safety is limited to clinically node negative patients. The purpose of this study was to evaluate the oncologic safety of local flaps in clinically node positive patients. Methods: Retrospective analysis of data available of all patients diagnosed with clinically node positive oral squamous cell carcinoma who underwent modified radical neck dissection at Malabar Cancer Centre during the period January 2012 to December 2017 was done. Demographic profile, tumour characteristics and pathological outcomes were compiled. The factors included were pathological tumour, nodal stage, levels of nodes involved, extranodal extension, choice of flap and site of recurrence. Fisher's exact test was used to compare recurrence patterns between local and regional flaps. Results: A total of 309 clinically node positive patients were analyzed with a median follow up of 4 years. Overall incidence of pathologically proven nodal metastases to ipsilateral levels Ia Ib, II, III, IV and V were 8.1%, 35.3%, 39.5%,15.5%, 2.9% and 1.3% respectively. Level Ia was most commonly involved in buccal mucosa and tongue cancers. Levels Ib, II, III were most commonly involved in tongue and buccal mucosa cancers. Level IV was commonly involved in tongue cancers while level V in cancer of retromolar trigone. Local flaps analyzed were submental flap (2.6%), supraclavicular flap (2.6%), infrahyoid flap (2.6%), sternocleidomastoid muscle flap (4.5%), nasolabial flap (1.3%), facial artery myomucosal flap (1.6%). Pathological nodal positivity was 60% and 52% in local and regional flaps respectively. Amongst the patients who had reconstruction with submental flap there were no nodal recurrences at level Ia, only 1 patient had recurrence at flap site. Amongst the patients who had reconstruction with supraclavicular flap there was 1 patient with pathological involvement of level V as per histopathological report but no nodal recurrences at level V. There was no difference in pattern of nodal recurrence between local and regional flaps (p = 0.436). Conclusions: This retrospective analysis is the first of its kind analysing the oncological safety of harvesting local flaps in clinically node positive oral squamous cell carcinoma. Thus, with appropriate management of the levels Ia and V nodal compartment, oncologic outcomes are not compromised, thereby making it oncologically sound to harvest local flaps in N+ neck.