Lower lymph node yield following neoadjuvant therapy for rectal cancer has no clinical significance

Kuo

et al. 2019

Preprint

Background Studies reporting the results of associated factors of pathological completed response (PCR) and tumor regression response in patients with rectal cancer following neoadjuvant chemoradiation therapy (nCRT) are inconsistent. The purpose of this study was to identify the prognostic factors of tumor response and outcome in rectal cancer patients.Methods The study was a retrospective analysis. Patients with locally advanced rectal cancer underwent nCRT followed by surgery from 2010 to 2014 with 5 years of follow-up. The primary outcomes were associated factors of pathological completed response and downstaging. The risk factors of survival outcome and disease recurrence were also observed.Results A total of 169 rectal cancer patients were included. The PCR rate was 17.8%, and the downstaging rate was 60.9%. Patients with a histology type of adenocarcinoma associated with PCR, and patients positive for clinical N stage were associated with downstaging. Kaplan-Meier analysis showed the PCR group performed better to a statistically significant level both in overall survival and disease recurrence free survival than the no PCR group (p= 0.033 & 0.025, respectively). Patients with a downstaging response also showed better overall survival benefits and disease recurrence free survival benefits than their counter-parts (both p<0.001). After controlling confounding variables, the risk factors of overall survival were downstaging [Hazard Ratio (HR): 0.40, 95% CI: 0.21-0.74], male, abnormal post-nCRT CEA level and abnormal Hb level. In addition, the protective factors of recurrence were downstaging and having adjuvant chemotherapy.Conclusions Among rectal cancer patients who received the neoadjuvant therapy, histology type and clinical N stage were associated with PCR and downstaging, respectively. Downstaging was an important protective factor for better overall survival and recurrence free survival.

Section: Discussionsupporting

confidence: 90%

Pathological Response Has Survival Benefits for Rectal Cancer following Neoadjuvant Therapy

Kuo

et al. 2019

Preprint

“…Also, our study demonstrated no difference between those with less than 12 lymph nodes and those with more than 12 lymph nodes regarding OS and DFS. These findings are supported by a recent study that demonstrated that though NACRT reduces the lymph nodal yield, it still has no significance on the survival of the patient [30].…”

Section: Discussionsupporting

confidence: 61%

Lymph Node Ratio as a Prognostic Marker in Rectal Cancer Survival: A Systematic Review and Meta-Analysis

Karjol

Jonnada

Chandranath

et al. 2020

Cureus

The lymph node ratio (LNR) is defined as the ratio of the number of positive lymph nodes to the total number of nodes retrieved. LNR has recently emerged as a prognostic factor in rectal cancer. The objective of our study was to pool eligible studies to elucidate the prognostic role of LNR on overall survival (OS) and disease-free survival (DFS) in rectal cancer patients using a meta-analysis. Methods A systematic database search was performed in MEDLINE and Embase for relevant studies that reported LNR in rectal cancer. Two authors independently screened the relevant articles for selection and data extraction. As a result, a list of such studies and references, published in English up to December 2019, was obtained, and a total of 4,486 node-positive patients in 18 studies were included in this meta-analysis. RevMan software 5.3 (Cochrane Collaboration, the Nordic Cochrane Centre, Copenhagen) was used for conducting all statistical analyses. Results A higher LNR was significantly correlated with worse OS [hazard ratio (HR): 2.60; 95% confidence interval (CI): 2.21-3.06; p≤.00001] and DFS (HR: 2.43; 95% CI: 2.11-2.80; p≤.00001) in node-positive rectal cancer patients. Besides, LNR is an independent predictive and prognostic marker of OS and DFS (HR: 2.52; 95% CI: 2.17-2.94; p≤.00001 with I 2 =0%; p=.32 and HR: 2.63; 95% CI: 2.17-3.18; p≤.00001 with I 2 =0%; p=.63 respectively, irrespective of lymph nodal harvest). Conclusions Our present study demonstrates that LNR is an independent predictor of survival in rectal cancer. LNR should be considered as a parameter in future oncological staging systems. Further well-designed randomized control trials to prospectively assess LNR as an independent predictor of rectal cancer survival are necessary before its application in daily practice.

“…Lastly, our results are especially pertinent to our local population, as it allows us to apply these results to patients from a similar background. A recent local paper published by Chan et al demonstrated that the LNH cut-off of 12 had no significant impact on overall survival in patients who received neoadjuvant therapy [22]. Perhaps, a new lower cut-off of 9 can be used in our local population instead.…”

Section: Discussionmentioning

confidence: 99%

A lower cut-off for lymph node harvest predicts for poorer overall survival after rectal surgery post neoadjuvant chemoradiotherapy

et al. 2020

Background: A lymph node harvest (LNH) of < 12 is a predictor for poor prognosis in rectal cancer patients. However, neoadjuvant chemoradiotherapy (NACRT) is known to decrease LNH; hence, a cutoff of 12 is inappropriate in such patients. This paper aims to establish a LNH cutoff predictive for disease-free and overall survival in NACRT patients. Methods: A retrospective review of patients who underwent elective surgery for rectal cancer from 2006 to 2013 was performed. All patients with R1/2 resections and presence of metastases and those operated on for recurrence were excluded. Patient demographics, clinical features, operative details, LNH, 30-day mortality and disease-free and overall survival were recorded. P values of < 0.05 were considered significant. Results: A total of 257 patients were studied, with 174 (68%) males and a median age of 66 years. Ninety-four (37%) patients received long-course NACRT, and 122 (48%) patients were stage 2 and below. Median LNH was 17, which was reduced in the NACRT group (14 versus 23, P < 0.01). Average length of stay was 9 ± 8 days, with a major post-operative complication rate of 4%. Using hazard ratio plots for the NACRT subgroup, LNH cutoffs of 16.5 and 8.5 were obtained for disease-free survival (DFS) and overall survival (OS) respectively. Survival analysis showed that a LNH cutoff of 8.5 was a significant predictor of OS (P < 0.001). Conclusion: LNH is reduced in patients receiving NACRT before rectal cancer surgery. A LNH of 9 and above is associated with improved overall survival. We propose that this can be used as a tool for prognosis.