Effect of lateral lymph node dissection for mid and low rectal cancer: An ad-hoc analysis of the ACTS-RC (JFMC35-C1) randomized clinical trial

Does Neoadjuvant Chemoradiotherapy Have an Additional Effect to Lateral Pelvic Lymph Node Dissection for Rectal Cancer?

Objectives

A total mesenteric excision (TME) with lateral pelvic lymph node dissection (LLND) is the standard treatment for advanced low rectal cancer in Japan. Recently, neoadjuvant (chemo)radiotherapy (n(C)RT) has been used with LLND to improve outcomes at multiple Japanese institutes. This study evaluates the benefits of adding nCRT to TME with LLND.

Methods

Seventy-two consecutive patients who underwent TME and LLND with or without nCRT between 2006-2019 to treat advanced low rectal cancer were retrospectively reviewed. The clinicopathological data were compared and the risk factors for local recurrence were evaluated.

Results

Fifty-seven patients (79.1%) underwent TME and LLND with nCRT, and 15 patients (20.9%) without nCRT. There was no significant difference in the clinicopathological characteristics except the clinical T stage. The occurrence of postoperative complications was statistically insignificant. The 5-year local recurrence rate of patients with nCRT was significantly lower than those without (4.0% versus 26.6%, in all patients, p=0.002). Multivariate analysis revealed that the absence of nCRT was an independent risk factor for local recurrences in patients who underwent TME with LLND (hazard ratio: 6.04, p=0.04).

Conclusions

The administration of nCRT prevented local recurrences more effectively in patients with advanced low rectal cancer who underwent TME with LLND.

Contemporary management of rectal cancer

The management of rectal cancer has undergone significant changes over the past 50 years, and this has been associated with major improvements in overall outcomes and quality of life. From standardization of total mesorectal excision to refinements in radiation delivery and shifting of chemoradiotherapy treatment to favor a neoadjuvant approach, as well as the development of targeted chemotherapeutics, these management strategies have continually aimed to achieve locoregional and systemic control while limiting adverse effects and enhance overall survival. This article highlights evolving aspects of rectal cancer therapy including improved staging modalities, total neoadjuvant therapy, the role of short-course and more selective radiotherapy strategies, as well as organ preservation. We also discuss the evolving role of minimally invasive surgery and comment on lateral pelvic lymph node dissection.

Key message

Rectal cancer management is constantly evolving through refinements in radiation timing and delivery, modification of chemoradiotherapy treatment schedules, and increasing utilization of minimally invasive surgical techniques and organ preservation strategies. This manuscript aims to provide a synopsis of recent changes in the management of rectal cancer, highlighting contemporary modifications in neoadjuvant approaches and surgical management to enhance the knowledge of surgeons who care for this challenging population.

Clinical implication and management of rectal cancer with clinically suspicious lateral pelvic lymph node metastasis: A radiation oncologist's perspective

Rectal cancer is the eighth most common malignancy worldwide. With the introduction of total mesorectal excision (TME) and neoadjuvant chemoradiation (NCRT), intrapelvic local control has been remarkably improved. However, lateral pelvic recurrence remains problematic, especially in patients with clinically suspicious lateral pelvic lymph node (LPLN). LPLN dissection has been applied for the management of LPLN metastasis, mainly in Japan and other Eastern countries, while the role of NCRT is more emphasized and LPLN dissection is performed in very limited cases in Western countries. However, the optimal management strategy for patients with rectal cancer with suspicious LPLN metastasis has not been determined. Herein, we review the latest studies on the optimal management of LPLN metastasis to suggest the most appropriate treatment policies according to current evidence and discuss future research directions.

Efficacy and Safety of Radical Resection of Rectal Cancer Combined with Selective Lateral Lymph Node Dissection in the Treatment of Low Rectal Cancer under Meta-analysis

Rectal cancer mostly occurs in the middle and low position in China, and many anatomical evidence has confirmed that Lateral Lymph Node Metastasis (LLNM) exists in middle and low rectal cancer. Laparoscopic surgery can penetrate into the pelvic cavity and magnify and narrow the visual field, which is helpful for lymph node dissection and vascular nerve protection, while it has minimally invasive characteristics and is considered to be more suitable for LLND. Relevant articles published from January 2000 to May 2022 are searched using "Rectal cancer, Lateral lymph node dissection, Radical resection of rectal cancer, Low rectal cancer, Laparoscopic therapy, Treatment of rectal cancer" as test terms, analyzed and assessed using Rev Man 5.3 software and Stata software to assess the risk bias of included references, and heterogeneity among each study is evaluated using Q test and heterogeneity (I2). The experimental results show that there is no heterogeneity among the studies (I2 = 8.46%). The heterogeneity of lymphatic metastasis in the included literature is evaluated, and the results show that there is heterogeneity between the studies (I2 = 52.06%).

Mesorectal excision with lateral lymph node dissection for mid-low rectal cancer with lateral lymph node metastasis: efficacy and prognostic analysis

Background

The aim of this study was to evaluate the efficacy of lateral pelvic lymph node (LPN) dissection (LPND) for rectal cancer patients with LPN metastasis (LPNM) and investigate the impact of LPNM on prognosis.

Methods

One hundred twenty-five matched pairs were selected and divided into the total mesorectal excision (TME) group and TME + LPND group for evaluation after propensity matching.

Results

No significant difference was observed in the 3-year local recurrence rate between the TME group and the TME + LPND group (10.7% vs 8.8%, P = 0.817); however, the rate of distant metastasis after TME + LPND was significantly higher (15.2% vs 7.2%, P = 0.044). When the mesorectal LN and LPN groups were subdivided, 3-year RFS was not significantly different between the internal LPN and N2 groups (57.1% vs. 55.3%, P = 0.613). There was no significant difference in RFS between the external group and the stage IV group (49.1% vs. 22.5%, P = 0.302), but RFS in the former group was significantly worse than that in the N2 group (49.1% vs. 55.3%, P = 0.044).

Conclusion

Although patients with suspected LPNM can achieve satisfactory local control after TME + LPND, systemic metastases are more likely to develop after surgery. Patients limited to internal iliac and obturator LN metastasis appear to achieve a survival benefit from LPND and can be regarded as regional LN metastasis. However, patients with LPNM in the external and common iliac LN metastasis have a poor prognosis that is significantly worse than that of N2 and slightly better than that of stage IV, and LPND should be carefully selected.

Extended Lymphadenectomy in Locally Advanced Rectal Cancers: A Systematic Review

Purpose

The surgical treatment of advanced low rectal cancer remains controversial. Extended lymphadenectomy (EL) is the preferred option in the East, especially in Japan, while neoadjuvant radiotherapy is the treatment of choice in the West. This review was undertaken to review available evidence supporting each of the therapies.

Methods

All studies looking at EL were included in this review. A comprehensive search was conducted as per PRISMA guidelines. Primary outcome was defined as 5-year overall survival, with secondary outcomes including 3-year overall survival, 3- and 5-year disease-free survival, length of operation, and number of complications.

Results

Thirty-one studies met the inclusion criteria. There was no significant publication bias. There was statistically significant difference in 5-year survival for patient who underwent EL (odds ratio, 1.34; 95 confidence interval, 0.09–0.5; P=0.006). There were no differences noted in secondary outcomes except for length of the operations.

Conclusion

There is evidence supporting EL in rectal cancer; however, it is difficult to interpret and not easily transferable to a Western population. Further research is necessary on this important topic.

The additional diagnostic impact of positron emission tomography-computed tomography for lymph node metastasis from colorectal cancer: A prospective lymph node level analysis

BACKGROUND

We conducted a prospective study to determine the diagnostic performance of positron emission tomography-computed tomography (PET-CT) for lymph node metastasis in colorectal cancer patients.

METHODS

We enrolled patients scheduled to receive curative surgery with lymph node dissection for colorectal adenocarcinoma who underwent contrast-enhanced abdominopelvic CT and PET-CT before surgery and who had primary lesions of cT2 or deeper. A radiologist determined the fluorodeoxyglucose uptake and the standardized uptake value (SUV) and metabolic volume (MV) to diagnose metastasis in cases with enlarged lymph nodes (≥7 mm long in minor diameter) on contrast-enhanced CT. Two gastrointestinal surgeons intraoperatively identified target lymph nodes to assess the association between images and pathological findings. The diagnostic performance (i.e., sensitivity, specificity, and positive and negative predictive values) for lymph node metastasis was determined using multilevel logistic modeling.

RESULTS

A total of 205 colorectal cancer patients were enrolled from February 2018 to April 2020 and 194 patients were analyzed in this study. The sensitivity, specificity, and positive and negative predictive values of PET-CT were 15.3% (13.4%-17.5%), 100.0% (99.0%-100.0%), 100.0% (51.2%-100.0%), and 98.7% (98.5%-99.0%), respectively.

CONCLUSION

PET-CT is a useful modality for determining the presence of metastasis in swollen lymph nodes on contrast-enhanced CT in colorectal cancer patients.

Prognostic Value of Lateral Pelvic Lymph Node Dissection for Rectal Cancer: A Meta-analysis

BACKGROUND AND AIMS

The benefit of lateral pelvic lymph node dissection (LPLD) for locally advanced rectal cancer remains controversial. This meta-analysis aimed to evaluate the prognostic value of LPLD in patients with locally advanced rectal cancer.

METHODS

We performed a systematic search in PubMed, Embase, and the Cochrane Library for publications comparing radical resection plus LPLD (LPLD group) with single radical resection (non-LPLD group) for locally advanced rectal cancer. A total of 15 studies satisfied our inclusion criteria and were assessed. Random-effects and fixed-effects meta-analytical models were used where indicated, and between-study heterogeneity was assessed.

RESULTS

LPLD significantly increased grade 3-4 postoperative complications (odds ratio [OR]1.44, 95% CI 1.03-2.02; P = 0.03) compared with non-LPLD. There were no significant differences in 5-y overall survival (hazard ratio = 0.90, 95% CI 0.77-1.05; P = 0.17), 5-y disease-free survival (hazard ratio 1.12, 95% CI 0.60-2.09; P = 0.73), local recurrence (OR 0.89, 95% CI 0.53-1.51; P = 0.68) or distant recurrence (OR 0.85, 95% CI 0.64-1.12; P = 0.24).

CONCLUSIONS

We found that LPLD significantly increased grade 3-4 postoperative complications but did not increase 5-y overall survival or 5-y disease-free survival compared with single radical resection for locally advanced rectal cancer. Furthermore, it did not decrease the local recurrence or distant recurrence rates. Thus, more multicenter large-scale randomized controlled trials should be conducted to further explore whether the long-term survival benefits of LPLD truly exist.

Meta-analysis of direct-to-surgery lateral pelvic lymph node dissection for rectal cancer

AIM

Direct-to-surgery rectal resection with lateral pelvic lymph node dissection (LPLND) is a treatment strategy commonly employed in Japan to improve oncological outcomes for rectal cancer. The aim of this study was to assess oncological outcomes in the literature for patients with low rectal cancer who underwent direct-to-surgery resection and LPLND compared with those who underwent total mesorectal excision (TME) alone.

METHOD

A literature search of Medline, Embase and PubMed databases was performed to identify relevant studies published between 1989 and 2020. The primary outcomes were 5-year overall survival (OS) and 5-year disease-free survival (DFS). The secondary outcomes were cancer recurrence (local, distant and total) and operative burden (operative time and blood loss). Pooled relative risk (RR) of oncological outcomes was performed using the DerSimonian-Laird method random-effect model.

RESULTS

Twenty-one studies fulfilled inclusion criteria, including 19 nonrandomized studies of interventions and two studies from one randomized controlled trial. No differences were observed in 5-year OS or 5-year DFS. Local recurrence in nonrandomized studies was worse in patients who underwent LPLND [RR 1.41 (95% CI 1.21-1.64, p < 0.001)], as was total recurrence [RR 1.44 (95% CI 1.25-1.67, p < 0.001)]. No differences were observed for distant recurrence.

CONCLUSION

In the published literature, direct-to-surgery resection with LPLND was associated with worse local and total recurrence. These predominantly nonrandomized data suggest that a nonselective approach to LPLND does not provide optimal management in radiotherapy-naïve patients with low rectal cancer. Further prospective randomized studies with a focus on patient selection are required.

Lateral lymph node dissection for mid-to-low rectal cancer: is it safe and effective in a practice-based cohort?

BACKGROUND

Most evidence regarding lateral lymph node dissection for rectal cancer is from expert settings. This study aimed to evaluate the safety and efficacy of this procedure in a practice-based cohort.

METHODS

A total of 383 patients who were diagnosed with stage II-III mid-to-low rectal cancer between 2010 and 2019 and underwent primary resection with curative intent at a general surgery unit were retrospectively reviewed. After propensity matching, 144 patients were divided into the following groups for short- and long-term outcome evaluation: mesorectal excision with lateral lymph node dissection (n = 72) and mesorectal excision (n = 72).

RESULTS

This practice-based cohort was characterized by a high pT4 (41.6%) and R1 resection (10.4%) rate. Although the operative time was longer in the lateral dissection group (349 min vs. 237 min, p < 0.001), postoperative complications (19.4% vs. 16.7%, p = 0.829), and hospital stay (18 days vs. 22 days, p = 0.059) did not significantly differ; 5-year relapse-free survival (62.5% vs. 66.4%, p = 0.378), and cumulative local recurrence (9.7% vs. 15.3%, p = 0.451) were also in the same range in both groups. In the seven locally recurrent cases in the lateral dissection group, four had undergone R1 resection.

CONCLUSIONS

Lateral lymph node dissection was found to be safe in this practice-based cohort; however, the local control effect was not obvious. To maximize the potential merits of lateral lymph node dissection, strategies need to be urgently established to avoid R1 resection in clinical practice.

Rise and fall of total mesorectal excision with lateral pelvic lymphadenectomy for rectal cancer: an updated systematic review and meta-analysis of 11,366 patients

The role of lateral lymph node dissection (LLND) during total mesorectal excision (TME) for rectal cancer is still controversial. Many reviews were published on prophylactic LLND in rectal cancer surgery, some biased by heterogeneity of overall associated treatments. The aim of this systematic review and meta-analysis is to perform a timeline analysis of different treatments associated to prophylactic LLND vs no-LLND during TME for rectal cancer.

METHODS

A literature search was performed in PubMed, SCOPUS and WOS for publications up to 1 September 2020. We considered RCTs and CCTs comparing oncologic and functional outcomes of TME with or without LLND in patients with rectal cancer.

RESULTS

Thirty-four included articles and 29 studies enrolled 11,606 patients. No difference in 5-year local recurrence (in every subgroup analysis including preoperative neoadjuvant chemoradiotherapy), 5-year distant and overall recurrence, 5-year overall survival and 5-year disease-free survival was found between LLND group and non LLND group. The analysis of post-operative functional outcomes reported hindered quality of life (urinary, evacuatory and sexual dysfunction) in LLND patients when compared to non LLND.

CONCLUSION

Our publication does not demonstrate that TME with LLND has any oncological advantage when compared to TME alone, showing that with the advent of neoadjuvant therapy, the advantage of LLND is lost. In this review, the most important bias is the heterogeneous characteristics of patients, cancer staging, different neoadjuvant therapy, different radiotherapy techniques and fractionation used in different studies. Higher rate of functional post-operative complications does not support routinely use of LLND.

Outcome of lateral pelvic lymph node dissection with total mesorectal excision in treatment of rectal cancer: A systematic review and meta-analysis

BACKGROUND

Total mesorectal excision is the gold standard treatment of mid- and low-lying rectal cancer. Lateral pelvic lymph node dissection has been suggested as an approach to decrease recurrence and improve survival. Our meta-analysis presented here aimed to review the current outcomes of lateral pelvic lymph node dissection and total mesorectal excision in comparison with total mesorectal excision alone.

METHODS

A systematic literature search querying electronic databases was conducted in accordance with the Preferred Reporting Items for Systematic reviews and Meta-Analyses guidelines. We reviewed articles that reported the outcomes of lateral pelvic lymph node dissection combined with total mesorectal excision in comparison with total mesorectal excision alone. The main outcome measures were local recurrence, distant metastasis, overall and disease free-survival, and complications.

RESULTS

This systematic review included 29 studies of 10,646 patients. Of those patients, 39.4% underwent total mesorectal excision with lateral pelvic lymph node dissection. The median operation time for the lateral pelvic lymph node dissection + total mesorectal excision was significantly longer than total mesorectal excision alone (360 minutes versus 294.7 minutes, P = .02). Lateral pelvic lymph node dissection + total mesorectal excision was associated with higher odds of overall complications (odds ratio = 1.48, 95% confidence interval: 1.18-1.87, P < .001) and urinary dysfunction (odds ratio = 2.1, 95% confidence interval: 1.21-3.67, P = .008) than total mesorectal excision alone. Both groups had similar rates of male sexual dysfunction (odds ratio = 1.62, 95% confidence interval: 0.94-2.79, P = .08), anastomotic leakage (odds ratio = 1.15, 95% confidence interval: 0.69-1.93, P = .59), local recurrence (hazard ratio = 0.96, 95% confidence interval: 0.75-1.25, P = .79), distant metastasis (hazard ratio = 0.96, 95% confidence interval: 0.76-1.2, P = .72), overall survival (hazard ratio = 1.056, 95% confidence interval: 0.98-1.13, P = .13), and disease-free survival (hazard ratio = 1.02, 95% confidence interval: 0.97-1.07, P = .37).

CONCLUSION

Lateral pelvic lymph node dissection was not associated with a significant reduction of recurrence rates or improvement in survival as compared with total mesorectal excision alone; however, LPLND was associated with longer operation time and increased complication rate.

Lateral lymph node dissection reduces local recurrence of locally advanced lower rectal cancer in the absence of preoperative neoadjuvant chemoradiotherapy: a systematic review and meta-analysis

Background

The impact of lateral lymph node dissection (LLND) in locally advanced lower rectal cancer remains controversial. This study is to compare total mesorectal excision (TME) with or without LLND in lower rectal cancer cases of stage II/III.

Methods

The electronic databases were systematically searched that compared TME with or without LLND among patients with lower rectal cancer in clinical stage II/III. Subgroup analysis was performed considering neoadjuvant chemoradiotherapy (nCRT). The hazard ratios (HR), relative risk (RR), and weighted mean difference (WMD) were pooled.

Results

Twelve studies of 4458 patients of this meta-analysis demonstrate, LLND alone significantly reduced the local recurrence rate of patients who did not receive nCRT (RR 0.71, P = 0.004), while the difference was not significant when combined with nCRT (RR 0.70, P = 0.36). The analysis shows TME with LLND was associated with significantly longer operation time (WMD 90.73 min, P < 0.001), more intraoperative blood loss (WMD 303.20 mL, P < 0.001), and postoperative complications (RR = 1.35, P =0.02). Whereas urinary dysfunction (RR 1.44, P = 0.38), sexual dysfunction (RR 1.41, P = 0.17), and postoperative mortality (RR = 1.52, P = 0.70), were similar between these two groups. Statistically, no significant differences were observed in OS (HR 0.93, P = 0.62), DFS (HR 0.99, P = 0.96), total recurrence (RR 0.98, P = 0.83), lateral recurrence (RR 0.49, P = 0.14), or distal recurrence (RR 0.95, P = 0.78) between these two groups regardless of whether nCRT was performed or not.

Conclusions

The study shows LLND alone decreases the local recurrence without using nCRT irrespective of the survival advantage in locally advanced lower rectal cancer. The benefit of controlling local recurrence by LLND alone makes us reconsider the usage of nCRT with LLND.

Trial registration

The protocol for this meta-analysis was registered prospectively with PROSPERO (CRD42020135575) on 16 May 2019.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12957-020-02078-1.

Total mesorectal excision with and without lateral lymph node dissection: a systematic review of the literature

PURPOSE

Treatment of lateral lymph node metastasis in rectal cancer is still under debate. While these nodes are routinely resected by Japanese teams, neoadjuvant radiochemotherapy alone is performed in Western countries. We aimed to systematically report the current literature assessing the overall and disease-free survivals of patients with rectal cancer treated with total mesorectal resection (TME) with or without lateral lymph node dissection (LLND).

METHODS

MEDLINE/Pubmed, Embase, Cochrane, and Web of Science were searched from database implementation until 19 January 2019. Studies reporting overall survival or recurrence-free survival in patients with LLND for rectal cancer were included. We excluded studies including patients with recurrent rectal cancer, multivisceral resection, and/or without control group (patients with rectal surgery without LLND).

RESULTS

Eleven studies were included, accounting for a total of 4159 patients. Overall survival ranged between 55.6 and 92.6% for TME with LLND versus 49.2 and 90.2% for TME alone, with one study reporting statistically significant benefit of LLND. Recurrence-free survival ranged between 58.3 and 74.1% for TME with LLND versus 39.5 and 76.5% for TME alone. Two studies showed statistically significant differences between the two strategies, one randomized controlled trial showed improved recurrence-free survival in TME alone group (74.5% versus 74.1% with LLND at 5 years) and one observational retrospective study reported increased recurrence-free survival with more extensive resection (65.4% versus 39.5% without LLND, at 5 years).

CONCLUSION

Benefits of LLND are not clear and further randomized controlled trials should be performed to determine which strategy would allow improving survival in rectal cancer patients.

TRIAL REGISTRATION

The study protocol was registered in PROSPERO prior to study screening (CRD42019123181) and published in September 2019.

Long-term follow-up of the randomized trial of mesorectal excision with or without lateral lymph node dissection in rectal cancer (JCOG0212)

BACKGROUND

Japan Clinical Oncology Group (JCOG) 0212 (ClinicalTrials.gov NCT00190541) was a non-inferiority phase III trial of patients with clinical stage II-III rectal cancer without lateral pelvic lymph node enlargement. The trial compared mesorectal excision (ME) with ME and lateral lymph node dissection (LLND), with a primary endpoint of recurrence-free survival (RFS). The planned primary analysis at 5 years failed to confirm the non-inferiority of ME alone compared with ME and LLND. The present study aimed to compare ME alone and ME with LLND using long-term follow-up data from JCOG0212.

METHODS

Patients with clinical stage II-III rectal cancer below the peritoneal reflection and no lateral pelvic lymph node enlargement were included in this study. After surgeons confirmed R0 resection by ME, patients were randomized to receive ME alone or ME with LLND. The primary endpoint was RFS.

RESULTS

A total of 701 patients from 33 institutions were assigned to ME with LLND (351) or ME alone (350) between June 2003 and August 2010. The 7-year RFS rate was 71.1 per cent for ME with LLND and 70·7 per cent for ME alone (hazard ratio (HR) 1·09, 95 per cent c.i. 0·84 to 1·42; non-inferiority P = 0·064). Subgroup analysis showed improved RFS among patients with clinical stage III disease who underwent ME with LLND compared with ME alone (HR 1·49, 1·02 to 2·17).

CONCLUSION

Long-term follow-up data did not support the non-inferiority of ME alone compared with ME and LLND. ME with LLND is recommended for patients with clinical stage III disease, whereas LLND could be omitted in those with clinical stage II tumours.