Prognostic factors and related complications/sequalae of squamous cell carcinoma located in the gingivobuccal complex

Abstract

Background: Gingivobuccal complex (GBC) was a relatively new concept of oral subsite that was comprises of the upper and/or lower gingiva, gingival buccal sulcus, and adjacent buccal mucosa. Squamous cell carcinoma (SCC) of the GBC had a poor prognosis, with few studies analyzing this particular entity. The objective of this study was to analyze the risk factors affecting the prognosis and complications/sequalae of gingivobuccal complex cancer.

Methods: Between December 2014 and August 2019, a total of 122 patients diagnosed with primary gingivobuccal complex cancer in Beijing Stomatological Hospital, Capital Medical University were enrolled in the study. Through outpatient reviewed and telephone followed-up for 2-5 years postoperatively, postoperative relapse and complications/sequalae were assessed. The primary outcome parameter was 2-year disease-free survival.

Results: The most common central site of the tumor was the buccal mucosa (45.1%), followed by the lower gingiva (36.9%). The most diseases were pT4a (45.1%) and there was lymph node invasion (pN+) in 41.8% of patients. Moderate differentiated squamous carcinoma (77.9%) accounted for the vast majority of the histopathological differentiation. A total of 62.3% of tumors invaded the bone, while, 5.7% invaded the skin layer. Survival analysis found that 44.3% of patients experienced relapse within two years postoperatively and the mortality rate after relapse was 75.9%. Almost 60.0% of the tumors involving the maxilla and/or mandible developed relapse. Cox proportional hazards model found that pN stage (p= 0.002) and bone invasion (p= 0.007) were significant independent predictors of 2-year disease-free survival. Importantly, 63.1% of patients had postoperative (and postradiotherapy) complications/sequalae. It was noteworthy that 18 of 43 patients (41.9%) who implanted with titanium plates had hardware-related complications/sequalae, and the most of them were titanium plate exposure (61.1%).

Conclusions: Squamous cell carcinoma of the gingivobuccal complex cancer, as a new subsite worthy of attention in oral cancer, has a high complication/sequalae rate, high relapse rate and poor prognosis.

Trial registration: Prospective, Observational, Real-world Oral Malignant Tumors Study ( clinicaltrials.gov identifier: NCT02395367). The approval of the Institutional Review Board of the Beijing Stomatological Hospital of Capital Medical University (Approval number: CMUSH-IRB-KJPJ-2015-08).

Keywords: Bone invasion; Gingivobuccal complex cancer; Hardware-related complication; Oral squamous cell carcinoma; Sequalae.

Conflict of interest statement

The authors declare that they have no conflicts of interest to this work.

© 2022. The Author(s).

Figures

Fig. 1

Typical primary tumor of GBC cancer (A); The defect after en bloc resection of the primary tumor and neck lymph tissue (B); Specimens of primary tumor and neck dissection (C); Reconstruction using a free fibula flap and rigid internal fixation (the arrow shows that only the skin and subcutaneous tissue will cover the surface of the fibular flap and the reconstructed titanium plate, and the platysma and buccal muscles have been removed) (D); Profile image at one week postoperatively (the arrow shows that only the thin layer of skin and subcutaneous tissue was wrapped on the outside of the titanium plate) (E); Orthopantomography one week postoperatively (F)

Fig. 2

K-M curves drawn by dividing pathological T stage into early (pT1 and pT2) and late (pT3 and pT4) stages (A); K-M curves drawn by dividing pathological N stage into pN0 and pN+ (pN1, pN2 and pN3) (B)

Fig. 3

K-M curves comparing whether the jaw was involved