Department of Colorectal Surgery, Digestive Disease and Surgery Institute, Cleveland Clinic, Cleveland, Ohio.
Dis Colon Rectum. 2019 Jan;62(1):33-39. doi: 10.1097/DCR.0000000000001239.
Disease-free survival estimated from the time of surgery does not account for the changing likelihood of survival based on time already accrued. Conditional disease-free survival is defined as the probability of remaining disease free after reaching a specific time point without recurrence.
The purpose of this study was to evaluate conditional disease-free survival for patients with rectal cancer who were treated by proctectomy after neoadjuvant chemoradiation.
Demographics, tumor characteristics, and tumor regression scores were assessed. Three-year conditional disease-free survival was estimated at x year after surgery based on the formula cDFS3 = DFS(x+3)/DFS(x), where DFS is disease-free survival and cDFS is conditional disease-free survival. Analyses were performed using Cox proportional hazards models.
The study was conducted at a single tertiary referral center.
A total of 545 patients with rectal cancer who were treated by neoadjuvant chemoradiation and curative intent surgery between 1992 and 2012 were included.
Disease-free survival and conditional disease-free survival were measured.
The median patient age was 57.5 years, and 28.4% were women. Median follow-up was 5.9 years. Disease-free survival at 1, 3, and 5 years was 89%, 71%, and 63%. The probability of remaining disease free for an additional 3 years for patients disease free at 1, 3, and 5 years was 75%, 83%, and 82%. Tumor regression, pathologic stage, margin status, differentiation, and procedure (low anterior versus abdominoperineal resection) were associated with disease-free survival on multivariable analysis (p < 0.05), but their relevance varied over time. R1 resection and differentiation were initially significant but not at 5 years. In contrast, tumor regression after neoadjuvant chemoradiation had a long-lasting impact on survival (at 5 y, conditional disease-free survival for an additional 3 y: 91%, 85%, 76%, and 71% for regression scores 0, 1, 2, and 3; p = 0.002).
This was a retrospective study over 20 years, with evolution in adjuvant therapies during this time.
Conditional disease-free survival estimates improved over time, confirming that most patients will see a recurrence within the first few years. The impact of specific prognostic factors evolves variably over time. This information is useful to patients and providers and can help guide counseling and surveillance. See Video Abstract at http://links.lww.com/DCR/A771.
从手术时间估计的无疾病生存并不能反映基于已经累积的时间的生存可能性的变化。条件无疾病生存被定义为在达到特定时间点而无复发后保持无疾病的概率。
本研究旨在评估接受新辅助放化疗后行直肠切除术的直肠癌患者的条件无疾病生存。
评估人口统计学、肿瘤特征和肿瘤消退评分。根据公式 cDFS3 = DFS(x+3)/DFS(x)，在术后 x 年后估计 3 年条件无疾病生存，其中 DFS 是无疾病生存，cDFS 是条件无疾病生存。使用 Cox 比例风险模型进行分析。
研究在一家单一的三级转诊中心进行。
1992 年至 2012 年间，共纳入 545 例接受新辅助放化疗和根治性手术治疗的直肠癌患者。
无疾病生存和条件无疾病生存。
中位患者年龄为 57.5 岁，28.4%为女性。中位随访时间为 5.9 年。1、3 和 5 年无疾病生存率分别为 89%、71%和 63%。1、3 和 5 年无疾病的患者在另外 3 年内保持无疾病的概率分别为 75%、83%和 82%。肿瘤消退、病理分期、切缘状态、分化和手术方式（低位前切除术与经腹会阴切除术）在多变量分析中与无疾病生存相关（p < 0.05），但它们的相关性随时间而变化。R1 切除和分化在最初是显著的，但在 5 年后就不显著了。相比之下，新辅助放化疗后的肿瘤消退对生存有持久影响（在 5 年时，对于消退评分 0、1、2 和 3，额外 3 年的条件无疾病生存分别为 91%、85%、76%和 71%；p = 0.002）。
这是一项回顾性研究，历时 20 年，在此期间辅助治疗不断发展。
条件无疾病生存估计随着时间的推移而改善，证实大多数患者将在最初几年内看到复发。特定预后因素的影响随时间而异。这些信息对患者和提供者有用，并有助于指导咨询和监测。详见视频摘要，网址：http://links.lww.com/DCR/A771。
