Abstract：
OBJECTIVE: The choice of surgical approach for floor of the mouth (FOM) cancer, particularly for intermediate-stage tumors (cT2-cT3), remains controversial. This study aims to evaluate a method considering mylohyoid muscle (MM) invasion as a determinant for surgical approach selection, utilizing magnetic resonance imaging (MRI) preoperatively and frozen section (FS) analysis intraoperatively.
METHODS: This observational retrospective cohort study analyzed patients undergoing surgical resection of cT2 and cT3 FOM squamous cell carcinoma (SCC) between January 2013 and June 2023. MM infiltration assessed by preoperative MRI determined the surgical approach: clear infiltration led to compartmental surgery (CS), while doubtful or absent infiltration led to transoral surgery (TOS). Conversion from TOS to CS occurred intraoperatively based on macroscopic evidence or positive FS. Data collected included demographic, clinical, surgical, and pathological variables. Survival analysis was conducted using Kaplan-Meier method.
RESULTS: Among 44 patients included, majority had cT2 tumors (59.1%). MM resection was necessary in 22.7% of cases. Overall survival (OS) and progression-free survival (PFS) did not significantly differ between TOS and CS groups. Radiological depth of invasion (rDOI) < 10 mm is correlated with MM preservation in 89% of cases, while rDOI > 10 mm is correlated with MM resection only in 23.8% of cases. Pathological depth of invasion (pDOI) discrepancies were observed in the two groups: in CS group is shown a higher pDOI (> 10 mm) confirmation (90%). Surgical complications and functional outcomes differed between TOS and CS groups.
CONCLUSIONS: Considering MM invasion for surgical approach selection in cT2-cT3 FOM tumors appears oncologically safe, with better functional outcomes in muscle preservation. Preoperative MRI for MM assessment combined with intraoperative FS analysis provides reliable guidance for surgical decision-making.
METHODS: This observational retrospective cohort study analyzed patients undergoing surgical resection of cT2 and cT3 FOM squamous cell carcinoma (SCC) between January 2013 and June 2023. MM infiltration assessed by preoperative MRI determined the surgical approach: clear infiltration led to compartmental surgery (CS), while doubtful or absent infiltration led to transoral surgery (TOS). Conversion from TOS to CS occurred intraoperatively based on macroscopic evidence or positive FS. Data collected included demographic, clinical, surgical, and pathological variables. Survival analysis was conducted using Kaplan-Meier method.
RESULTS: Among 44 patients included, majority had cT2 tumors (59.1%). MM resection was necessary in 22.7% of cases. Overall survival (OS) and progression-free survival (PFS) did not significantly differ between TOS and CS groups. Radiological depth of invasion (rDOI) < 10 mm is correlated with MM preservation in 89% of cases, while rDOI > 10 mm is correlated with MM resection only in 23.8% of cases. Pathological depth of invasion (pDOI) discrepancies were observed in the two groups: in CS group is shown a higher pDOI (> 10 mm) confirmation (90%). Surgical complications and functional outcomes differed between TOS and CS groups.
CONCLUSIONS: Considering MM invasion for surgical approach selection in cT2-cT3 FOM tumors appears oncologically safe, with better functional outcomes in muscle preservation. Preoperative MRI for MM assessment combined with intraoperative FS analysis provides reliable guidance for surgical decision-making.
摘要：
目的：口底癌手术入路的选择，特别是对于中期肿瘤（cT2-cT3），仍然有争议。本研究旨在评估一种将舌骨肌（MM）侵袭作为手术入路选择决定因素的方法。术前利用磁共振成像（MRI）和术中冷冻切片（FS）分析。
方法：这项观察性回顾性队列研究分析了2013年1月至2023年6月期间接受cT2和cT3FOM鳞状细胞癌（SCC）手术切除的患者。术前MRI评估MM浸润确定手术入路：明确浸润导致房室手术（CS），而怀疑或缺乏浸润导致经口手术（TOS）。根据宏观证据或FS阳性，术中发生从TOS到CS的转换。收集的数据包括人口统计，临床,外科,和病理变量。采用Kaplan-Meier法进行生存分析。
结果：包括44例患者，大多数有cT2肿瘤（59.1%）。22.7%的病例需要MM切除。TOS组和CS组的总生存期（OS）和无进展生存期（PFS）没有显着差异。在89％的病例中，放射侵入深度（rDOI）<10mm与MM保留相关，而rDOI>10mm仅在23.8％的病例中与MM切除相关。在两组中观察到病理浸润深度（pDOI）差异：在CS组中显示出更高的pDOI（>10mm）确认（90％）。TOS组和CS组的手术并发症和功能结果不同。
结论：考虑到MM侵袭，cT2-cT3FOM肿瘤的手术入路选择在肿瘤学上是安全的，在肌肉保存方面具有更好的功能效果。术前MRI评估MM结合术中FS分析为手术决策提供可靠指导。
方法：这项观察性回顾性队列研究分析了2013年1月至2023年6月期间接受cT2和cT3FOM鳞状细胞癌（SCC）手术切除的患者。术前MRI评估MM浸润确定手术入路：明确浸润导致房室手术（CS），而怀疑或缺乏浸润导致经口手术（TOS）。根据宏观证据或FS阳性，术中发生从TOS到CS的转换。收集的数据包括人口统计，临床,外科,和病理变量。采用Kaplan-Meier法进行生存分析。
结果：包括44例患者，大多数有cT2肿瘤（59.1%）。22.7%的病例需要MM切除。TOS组和CS组的总生存期（OS）和无进展生存期（PFS）没有显着差异。在89％的病例中，放射侵入深度（rDOI）<10mm与MM保留相关，而rDOI>10mm仅在23.8％的病例中与MM切除相关。在两组中观察到病理浸润深度（pDOI）差异：在CS组中显示出更高的pDOI（>10mm）确认（90％）。TOS组和CS组的手术并发症和功能结果不同。
结论：考虑到MM侵袭，cT2-cT3FOM肿瘤的手术入路选择在肿瘤学上是安全的，在肌肉保存方面具有更好的功能效果。术前MRI评估MM结合术中FS分析为手术决策提供可靠指导。
