Hughes Ryan T, Farris Joshua, Steber Cole, Frizzell Bart A, Greven Kathryn M
Radiation Oncology, Wake Forest School of Medicine, Winston-Salem, USA.
Cureus. 2021 Feb 3;13(2):e13094. doi: 10.7759/cureus.13094.
Introduction Postoperative radiotherapy (PORT) is routinely recommended for patients with head and neck squamous cell carcinoma (HNSCC) based on pathologic risk factors (pRFs) such as perineural invasion (PNI). Patients with PNI as the sole pRF after resection of HNSCC are uncommon and their prognosis is less clear. The aim of this study is to assess the role of PNI as a sole risk factor in patients with otherwise pathologically low-risk HNSCC. Methods Patients with HNSCC of the oral cavity, pharynx, or larynx treated with primary surgical resection from 2013 to 2018 were identified from an institutional cancer registry. Those with pRFs (pathologic T3-4 disease, lymphovascular space invasion [LVSI], multiple positive lymph nodes, close [within 2 mm] or positive margins, extranodal extension [ENE], or recurrent disease) were excluded, yielding an otherwise pathologically low-risk cohort with or without incidental, pathologic PNI. Locoregional control (LRC), overall survival (OS) and disease-specific survival (DSS) were estimated and compared between PNI groups and by adjuvant therapy. Results A total of 1,058 patients were identified as having undergone surgical resection. Exclusion of patients with other pRFs, those with unknown PNI, and oral cavity patients with depth of invasion > 10 mm yielded a study cohort of 85 patients. Eight patients (10% of study group, <1% of all patients) had PNI as the sole pRF, none of which had clinical signs or symptoms of perineural tumor spread. The remaining 77 were negative for PNI and thus pathologically low risk. Patients with PNI were more likely to have oral cavity cancer, to be younger, and to have received PORT than those without PNI; no patient received concurrent chemotherapy. At a median follow-up of 46.4 months, two- and five-year LRC rates were 81.4% and 78.5%, respectively. No differences were noted between PNI-positive and PNI-negative groups (p=0.73) or PORT v. no-PORT groups (p=0.39). While the utility of PORT is not possible to assess given limited sample size, four patients with PNI who did not receive PORT did not experience locoregional failure. Seventeen patients overall experienced locoregional failure and 14 were ultimately salvaged. Five-year OS and DSS were 77.4% and 90.8%, respectively. Conclusion Patients with pathologically low-risk HNSCC after surgical resection experience high rates of LRC. In this large institutional cohort, PNI as the sole pRF was exceedingly rare, and the benefit of adjuvant therapies is difficult to assess. Within this limitation, PORT remains the standard of care for patients with PNI to reduce the risk of locoregional failure. Further collaborative studies are required to adequately assess the prognostic impact of PNI alone in resected HNSCC.
引言
基于病理危险因素（pRFs），如神经周围侵犯（PNI），术后放疗（PORT）通常被推荐用于头颈部鳞状细胞癌（HNSCC）患者。在HNSCC切除术后，PNI作为唯一pRF的患者并不常见，其预后也不太明确。本研究的目的是评估PNI作为唯一危险因素在其他方面病理低危HNSCC患者中的作用。
方法
从机构癌症登记处确定2013年至2018年接受原发性手术切除的口腔、咽或喉HNSCC患者。排除有pRFs（病理T3-4期疾病、淋巴管血管间隙浸润[LVSI]、多个阳性淋巴结、切缘接近（2mm内）或阳性、结外扩展[ENE]或复发性疾病）的患者，从而得出一个在其他方面病理低危的队列，无论有无偶然的病理PNI。估计并比较PNI组之间以及通过辅助治疗的局部区域控制（LRC）、总生存期（OS）和疾病特异性生存期（DSS）。
结果
共确定1058例患者接受了手术切除。排除有其他pRFs的患者、PNI未知的患者以及浸润深度>10mm的口腔患者后，得到一个85例患者的研究队列。8例患者（研究组的10%，所有患者的<1%）PNI作为唯一pRF，均无神经周围肿瘤扩散的临床体征或症状。其余77例PNI阴性，因此病理低危。与无PNI的患者相比，有PNI的患者更可能患口腔癌、更年轻且接受了PORT；没有患者接受同步化疗。中位随访46.4个月时，两年和五年LRC率分别为81.4%和78.5%。PNI阳性组和PNI阴性组之间（p=0.73）或PORT组与非PORT组之间（p=0.39）未发现差异。虽然由于样本量有限无法评估PORT的效用，但4例有PNI但未接受PORT的患者未发生局部区域失败。17例患者总体发生了局部区域失败，14例最终得到挽救。五年OS和DSS分别为77.4%和90.8%。
结论
手术切除后病理低危的HNSCC患者LRC率较高。在这个大型机构队列中，PNI作为唯一pRF极为罕见，辅助治疗的益处难以评估。在此限制范围内，PORT仍然是有PNI患者降低局部区域失败风险的标准治疗方法。需要进一步的合作研究来充分评估单独PNI对切除的HNSCC患者的预后影响。
