Neoadjuvant Chemoradiation Therapy for All Elderly Patients With Locally Advanced Rectal Cancer?

Abstract

Although the safety of rectal cancer surgery in very carefully selected elderly patients has been established, 1 data on the safety and efficacy of chemoradiation therapy in this patient population is limited. This may explain the relative underuse of radiation therapy in elderly individuals, first noted in 2001. 2 Nassoiy et al, 3 using the National Cancer Data Base in a multicenter retrospective design, demonstrate that only 58.8% of patients older than 80 years diagnosed with a locally advanced rectal cancer between 2004 and 2016 received neoadjuvant chemoradiation therapy (NACRT). Their secondary analysis led them to conclude that NACRT is associated independently with a 25% decreased risk of death compared with alternate treatment sequences (surgery + adjuvant therapy or surgery alone). However, their conclusion is based on an analysis of groups that, according to Table 1 in their article, 3 are statistically different. Although inverse probability of treatment weighting methodology was used to balance the groups, the authors do not provide any evidence that the groups were similar after inverse probability of treatment weighting adjustment. A preferred approach may have been to select patients with similar baseline characteristics, group them by treatment received, and then compare outcomes. Did the authors consider using propensity score matching methodology? Of equal concern is their decision to use binary logistic regression to compare 2 arbitrary groups (NACRT vs

How Can We Improve the Tumor Response to Preoperative Chemoradiotherapy for Locally Advanced Rectal Cancer?

“…The Lyon R 90-01 clinical trial found that pCRT increased the rate of pCR or near-pCR from 10.3% at two-week intervals to 26% at six to eightweek intervals. As a result, the optimal interval between CRT and surgery is currently considered to be six to eight weeks to improve pCR rates and reduce postoperative complications [28,29]. Despite encouraging results from trials that have extended the time between pCRT and surgery, there is still no definitive consensus on the time between the completion of pCRT and surgery, with current studies showing a cautious trend towards delaying surgery.…”

Management of Locally Advanced Rectal Cancer—Building the Plane as We Fly

“…The Interval Between Neoadjuvant Therapy and Surgery in the Treatment of Locally Advanced Rectal Cancer (CRONOS) study is a large multi-institutional retrospective analysis across several large hospitals in Spain. The authors should be commended on their effort and collaboration to bring together investigators across several large institutions and an impressive database of over 1500 patients.…”

“…Though important, the application of the conclusions of this article in the modern era of total neoadjuvant therapy (TNT) is unclear. Over the last decade, TNT is becoming more popular as the treatment of choice for locally advanced rectal cancer with the goal of higher rates of pathologic complete response .…”

“…Although this trial attempted to account for selection bias via propensity matching, the model is subject to shortcomings of all retrospective matching models in lieu of randomized clinical trial. The inverse probability of treatment weighting model used by the authors can be noted to have drastic differences in treatment intervals based on treatment location.…”

“…Despite the drawbacks in relevancy to current practice patterns, the study highlights the challenges faced with modern management of locally advanced rectal cancer. It also underscores the importance of the need to perform a large randomized clinical trial on the timing of surgery after radiation, especially if induction chemotherapy becomes more popularized …”