Lymph Node Harvest After Neoadjuvant Treatment for Rectal Cancer and Its Impact on Oncological Outcomes

Prognostic impact of log odds of positive lymph nodes (LODDS) in the stratification of patients with rectal cancer

INTRODUCTION

The use of the N category of the TNM staging system, lymph node ratio (LNR) and log odds of positive lymph nodes (LODDS) in predicting overall survival (OS) and disease-free survival (DFS) in patients with rectal cancer is still controversial.

MATERIAL AND METHODS

A retrospective study of 445 patients with rectal cancer who underwent surgery between 2008 and 2017 in the University Complex Hospital of Vigo was performed. Patients were stratified according to number of lymph nodes examined (NLNE), N staging, LNR and LODDS. The analysis was performed using the log-rank test, Kaplan-Meier functions, Cox regression and ROC curves.

RESULTS

Five-year OS and DFS were 73.7% and 62.5%, respectively. No statistically significant differences were observed depending on NLNE. Increased LNR and LODDS were associated with shorter OS and DFS, independently of NLNE. Multivariate analysis showed that N stage, LNR and LODDS were independently associated with OS and DFS; however, the LODDS system obtained the best area under the curve, with greater predictive capacity for OS (AUC: 0.679) and DFS (AUC: 0.711).

CONCLUSION

LODDS and LNR give prognostic information that is not related to NLNE. LODDS provides better prognostic accuracy in patients with negative nodes than LNR and N stage.

Short-term outcomes of short- and long-course chemoradiotherapy before total mesorectal excision for locally advanced rectal tumors: A single-center study in Taiwan utilizing propensity score matching

BACKGROUND

Locally advanced rectal tumors are typically treated with neoadjuvant chemoradiotherapy. Short-course chemoradiotherapy (SCRT, 2500 cGy in five fractions) is a convenient alternative to concurrent chemoradiotherapy with long-course radiotherapy (CCRT, 4500 cGy in 25 fractions) without sacrificing efficacy. We aimed to compare the short-term outcomes of SCRT and CCRT in patients with mid- and low- rectal tumors who underwent total mesorectal excision using real-world data.

METHODS

We retrospectively reviewed the data of patients with locally advanced rectal cancer who underwent radical resection after neoadjuvant chemoradiotherapy from 2011 to 2022. We analyzed the clinicopathological findings and prognostic factors for disease-free and overall survival in the SCRT and CCRT groups and compared the outcomes using propensity score matching.

RESULTS

Among the 66 patients in the two groups, no disparities were noted in the demographic features, pathological remission, or downstaging rates. Nonetheless, the SCRT group exhibited superior 3-year disease-free survival (81.8% vs 62.1%, p = 0.011), whereas the overall survival did not differ significantly between the two groups. The initial carcinoembryonic antigen (CEA) levels and neoadjuvant SCRT were associated with the recurrence rates [hazard ratio (HR) = 1.13-4.10; HR = 0.19-0.74], but the harvested lymph node count was not (HR = 0.51-1.97).

CONCLUSION

Among patients with locally advanced rectal cancer, SCRT combined with four cycles of FOLFOX was shown to enhance short-term disease-free survival. Factors impacting recurrence include the initial CEA level and SCRT, but not the harvested lymph node count.

Association between the number of retrieved lymph nodes and demographic/tumour-related characteristics in colorectal cancer: a systematic review and meta-analysis

OBJECTIVE

Clinical practice guidelines recommend retrieving at least 12 lymph nodes for correct staging in colorectal cancer. However, it is difficult to retrieve adequate lymph nodes because of various factors. We aimed to evaluate the association between the number of retrieved lymph nodes and demographic/tumour-related characteristics in colorectal cancer.

DESIGN

Systematic review and meta-analysis of primary studies.

DATA SOURCES

PubMed, Embase, Cochrane and Web of Science were searched from January 2016 to June 2023.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Studies that evaluated the association between retrieved lymph nodes and demographic/tumour-related characteristics in colorectal cancer were included.

DATA EXTRACTION AND SYNTHESIS

OR with 95% conference intervals was extracted and pooled.

RESULTS

A total of 54 studies containing 2 05 821 patients were included in this meta-analysis. The results showed that fewer nodes were retrieved from elderly patients (OR=0.70, 95% CI (0.54 to 0.90), p=0.005), and from tumours located in the left colon than in the right colon (OR=0.43, 95% CI (0.33 to 0.56), p<0.001). More lymph nodes were obtained from females than males (OR=1.15, 95% CI (1.04 to 1.28), p=0.006), from the advanced T stage (T3+T4) than T1+T2 stage (OR=1.57, 95% CI (1.25 to 1.97), p<0.001) and from the N2 stage than N0 stage (OR=1.32, 95% CI (1.15 to 1.51), p<0.001). Body mass index, ethnicity, N1 stage, M stage, tumour differentiation and lymph-vascular invasion were not significantly associated with the lymph node yield.

CONCLUSIONS

The study results suggest that clinicians have an increased opportunity to retrieve sufficient lymph nodes for accurate pathological staging to guide treatment decisions in patients with colorectal cancer who are young, female, with tumours located in the right colon, advanced T stage and N2 stage.

Propensity-score matched analysis of the pathologic outcomes and survival benefits of neoadjuvant therapy in stage II-III anal adenocarcinoma

BACKGROUND

Anal adenocarcinomas are a rare condition which account for less than 10% of anal cancers. The present study aimed to assess the impact of neoadjuvant therapy on the clinical and pathologic outcomes and overall survival (OS) of patients with stage II-III anal adenocarcinomas after abdominoperineal resection (APR).

METHODS

A retrospective cohort study of patients with anal adenocarcinoma in the US National Cancer Database (NCDB) (2010-2020) was conducted. Propensity-score matching was used to compare patients who received neoadjuvant therapy (neoadjuvant therapy group) to the no-neoadjuvant group. The primary outcome was 5-year OS whereas secondary outcomes included conversion to open surgery, hospital stay, surgical margins, 30-day mortality, 90-day mortality, and 30-day readmission.

RESULTS

A total of 742 patients (56% male) with a mean age of 63.6 ± 12.4 years were included. A total of 214 patients in the neoadjuvant group were matched with 107 in the no-neoadjuvant group. The mean OS was similar between the two groups (47.5 vs. 44.8 months, p = 0.253). Patients who received neoadjuvant therapy had a longer median time between diagnosis and surgery (151 vs. 54 days, p < 0.001), lower 90-day mortality (1.9% vs. 6.7%, p = 0.046), more pT0 tumors (15.7% vs. 0%), less pT3-4 tumors (28.4% vs. 36.4%, p = 0.001), less pN1-2 tumors (22.9% vs. 34.7%, p < 0.001), and less lymphovascular invasion (16.2% vs. 40%, p < 0.001) than the no-neoadjuvant group. Both groups had similar conversion rates, hospital stay, 30-day mortality, 30-day readmission, and positive surgical margins.

CONCLUSIONS

Neoadjuvant therapy before APR was associated with significant downstaging of anal adenocarcinomas and lower 90-day mortality, yet similar OS to patients who were surgically treated without neoadjuvant treatment.

Total Neoadjuvant Therapy in Rectal Cancer: Multi-center Comparison of Induction Chemotherapy and Long-Course Chemoradiation Versus Short-Course Radiation and Consolidative Chemotherapy

BACKGROUND

Total neoadjuvant therapy for locally advanced rectal cancer may include induction chemotherapy and chemoradiation or short-course radiotherapy and consolidative chemotherapy.

METHODS

Patients with clinical stage 2 or 3 rectal cancer who received induction chemotherapy followed by long-course chemoradiation at the University of Colorado (2016-2020) or short-course radiotherapy followed by consolidative chemotherapy at Washington University (2017-2020) were assessed.

RESULTS

Eighty-four patients received induction chemotherapy and chemoradiation and 83 received short-course radiotherapy and consolidative chemotherapy. Among patients with complete re-staging evaluation, clinical complete response rates were similar, 49% (18/37) and 53% (44/83), respectively (p = 0.659). In the induction chemotherapy and chemoradiation group, 80% (n = 67) underwent surgery and 28% (n = 19) achieved a pathologic complete response. In the short-course radiotherapy and consolidative chemotherapy group, 44 (53%) patients underwent surgery and 11% (n = 5) had a pathologic complete response. Overall, a complete response was observed in 43% (n = 36) of patients who received induction chemotherapy and chemoradiation compared to 53% (n = 44) who received short-course radiotherapy and consolidative chemotherapy (p = 0.189). Perioperative outcomes were similar in patients who received induction chemotherapy and chemoradiation compared to short-course radiotherapy and consolidative chemotherapy: intraoperative complications (2% vs 7%), complete mesorectal specimen (85% vs 84%), anastomotic leak (9% vs 7%), organ/space infection (9% vs 5%), readmission (19% vs 21%), and reoperation (8% vs 9%), respectively (all p > 0.05).

CONCLUSIONS

In patients with clinical stage 2 or 3 rectal cancer, total neoadjuvant therapy with either induction chemotherapy and chemoradiation or short-course radiotherapy followed by consolidative chemotherapy were associated with similar perioperative morbidity and complete response rates.