Invasion of the bucco-mandibular space by oral squamous cell carcinoma: histopathological analysis of invasion pattern

• Published in: Frontiers in oncology 2023-10, Vol.13, p.1168376-1168376
• Main Authors: Kugimoto, Takuma, Nishii, Naoto, Oikawa, Yu, Kuroshima, Takeshi, Hirai, Hideaki, Tomioka, Hirofumi, Michi, Yasuyuki, Kayamori, Kou, Sakamoto, Junichiro, Iwanaga, Joe, Tubbs, R. Shane, Ikeda, Tohru, Miura, Masahiko, Harada, Hiroyuki
• Format: Article
• Language: English
• Subjects: buccinator muscle; bucco-mandibular space; gingiva-buccal complex; mandible; Oncology; oral squamous cell carcinoma
• ISSN: 2234-943X; 2234-943X
• DOI: 10.3389/fonc.2023.1168376

BackgroundThis study aimed to determine the patterns of invasion of oral squamous cell carcinoma (OSCC) into the bucco-mandibular space (BMS) using detailed histopathological analysis and to assess clinical outcomes.MethodsPatients with OSCC who underwent segmental mandibulectomy or hemi-mandibulectomy combined with resection of the BMS between 2012 and 2021 were included. The invasions of the BMS were classified into three patterns. Pattern A was defined as a horizontal invasion, Pattern B as a vertical invasion, and Pattern C as an expansive invasion.ResultsIn total, 109 patients were reviewed. Of these 109 patients, the primary tumor affected the lower gingiva in 78 patients, the buccal mucosa in 18 patients, and was a primary intraosseous carcinoma of the mandible in 13 patients. Invasion of the BMS was significantly associated with a higher pathological T stage, positive/close margins, and lower disease-free survival (DFS) rates. The DFS rates were 86.7% and 66.0% in the BMS non-invasion and invasion groups, respectively. The DFS rates for each type of invasion were 82.1% for Pattern A, 67.4% for Pattern B, and 48.0% for Pattern C (P=0.277).ConclusionPatients with BMS invasion have a poorer prognosis than those without invasion of the BMS. Therefore, adjuvant therapy is necessary, especially in Patterns B and C. Evaluation of preoperative BMS invasion patterns is important for predicting the prognosis of OSCC.