Department of Pathology, Radboudumc, PO Box 9101, 6500 HB Nijmegen, the Netherlands.
Department of Clinical Oncology, Mount Vernon Cancer Centre, Rickmansworth Road, Northwood HA6 2RN, UK.
Cancer Treat Rev. 2020 Mar;84:101964. doi: 10.1016/j.ctrv.2020.101964. Epub 2020 Jan 17.
Various methods categorize tumour response after neoadjuvant therapy, including down-staging and tumour regression grading. Response categories allow comparison of different treatments within clinical trials and predict outcome. A reproducible response categorization could identify subgroups with high or low risk for the most appropriate subsequent treatments, like watch and wait. Lack of standardization and interpretation difficulties currently limit the usability of these approaches. In this review we describe these difficulties for the evaluation of chemoradiation in rectal cancer. An alternative approach of tumour response is based on patterns of residual disease, including fragmentation. We summarise the evidence behind this alternative method of response categorisation, which explains a number of very relevant clinical discrepancies. These issues include differences between downstaging and tumour regression, high local regrowth in advanced tumours during watchful waiting procedures, the importance of resection margins, the limited value of post-treatment biopsies and the relatively poor outcome of patients with a near complete pathological response. Recognition of these patterns of response can allow meaningful development of novel biomarkers in the future.
各种方法对新辅助治疗后的肿瘤反应进行分类，包括降期和肿瘤退缩分级。反应类别允许在临床试验中比较不同的治疗方法，并预测结果。可重复的反应分类可以确定具有高或低风险的亚组，以获得最合适的后续治疗，如观察和等待。目前，缺乏标准化和解释困难限制了这些方法的可用性。在这篇综述中，我们描述了这些在评估直肠癌放化疗中的困难。肿瘤反应的另一种方法基于残留疾病的模式，包括碎片化。我们总结了这种替代反应分类方法的证据，该方法解释了许多非常相关的临床差异。这些问题包括降期和肿瘤退缩之间的差异、在观察等待过程中晚期肿瘤的局部高复发率、切除边缘的重要性、治疗后活检的局限性以及接近完全病理反应患者的预后相对较差。认识到这些反应模式可以为未来有意义地开发新的生物标志物提供帮助。
