Department of Otorhinolaryngology, Head and Neck Surgery, Linkou Chang Gung Memorial Hospital and Chang Gung University, Taoyuan, Taiwan, ROC.
Department of Head and Neck Oncology Group, Linkou Chang Gung Memorial Hospital and Chang Gung University, Taoyuan, Taiwan, ROC.
Ann Surg Oncol. 2017 Sep;24(9):2570-2579. doi: 10.1245/s10434-017-5906-3. Epub 2017 Jun 3.
The identification of extrinsic tongue muscle invasion in oral cavity cancer remains challenging. Notably, the most recent American Joint Committee on Cancer (AJCC 2017, 8th edition) staging manual indicates that extrinsic muscle invasion does not lead to the diagnosis of a T4 tumor. Because this approach carries the risk of tumor downstaging, we compared the clinical outcomes of patients with oral tongue squamous cell carcinoma (SCC) staged as pT3 vs. pT4 according to the AJCC 2010, 7th edition criteria.
We retrospectively examined the records of consecutive patients with pT3 (n = 135) and pT4 (n = 68) tongue SCC who underwent radical surgery. Of the 68 pT4 tongue SCC, 63 (93%) had extrinsic muscle involvement alone. The 5-year locoregional control (LRC), distant metastasis (DM), and disease-free survival (DFS) rates served as outcome measures.
Compared with pT3 tongue SCC, pT4 patients presented significantly more frequently with pN2 disease, extranodal extension, poor tumor differentiation, tumor depth >15 and >20 mm, margin status ≤4 mm, perineural invasion, vascular invasion, and were more frequently treated with surgery plus concurrent chemoradiotherapy. Less favorable 5-year outcomes were observed in patients with pT4 than pT3 tumors (LRC 50 vs. 75%, p < 0.001; DM 27 vs. 14%, p = 0.013; DFS 43 vs. 69%, respectively, p < 0.001). We identified pT4 disease (vs. pT3) as an independent adverse prognostic factor for LRC and DFS.
We suggest classifying patients with tongue SCC and extrinsic muscle invasion as having pT4 disease.
口腔癌中外在舌肌侵犯的识别仍然具有挑战性。值得注意的是，最近的美国癌症联合委员会（AJCC 2017，第 8 版）分期手册表明，外在肌肉侵犯不会导致 T4 肿瘤的诊断。由于这种方法存在肿瘤降期的风险，我们比较了根据 AJCC 2010 第 7 版标准分期为 pT3 与 pT4 的口腔舌鳞癌（SCC）患者的临床结局。
我们回顾性检查了连续接受根治性手术治疗的 pT3（n=135）和 pT4（n=68）舌 SCC 患者的记录。在 68 例 pT4 舌 SCC 中，有 63 例（93%）仅存在外在肌肉侵犯。5 年局部区域控制（LRC）、远处转移（DM）和无病生存（DFS）率作为结局指标。
与 pT3 舌 SCC 相比，pT4 患者更常出现 pN2 疾病、结外延伸、肿瘤分化差、肿瘤深度＞15 和＞20mm、切缘状态≤4mm、神经周围侵犯、脉管侵犯，并且更常接受手术联合同期放化疗治疗。与 pT3 肿瘤相比，pT4 患者的 5 年结局较差（LRC 50%对 75%，p<0.001；DM 27%对 14%，p=0.013；DFS 43%对 69%，分别为 p<0.001）。我们发现 pT4 疾病（与 pT3 相比）是 LRC 和 DFS 的独立不良预后因素。
我们建议将有外在舌肌侵犯的舌 SCC 患者归类为 pT4 疾病。
