Extended lymph node dissection for rectal cancer with radiologically diagnosed extramesenteric lymph node metastasis

Standardize the surgical technique and clarify the oncologic significance of robotic D3-D4 lymphadenectomy for upper rectum and sigmoid colon cancer with clinically more than N2 lymph node metastasis

BACKGROUND

The territory of D3-D4 lymphadenectomy for upper rectal and sigmoid colon cancer varies, and its oncological efficacy is unclear. This prospective study aimed to standardize the surgical technique of robotic D3-D4 lymphadenectomy and clarify its oncologic significance.

METHODS

Patients with upper rectal or sigmoid colon cancer with clinically suspected more than N2 lymph node metastasis were prospectively recruited to undergo standardized robotic D3-D4 lymphadenectomy. Immediately postsurgery, the retrieved lymph nodes were mapped to five N3-N4 nodal stations: the inferior mesenteric artery, para-aorta, inferior vena cava, infra-renal vein, and common iliac vessels. Patients were stratified according to their nodal metastasis status to compare their clinicopathological data and overall survival. Univariate and multivariate analyses were performed to determine the relative prognostic significance of the five specific nodal stations. Surgical outcomes and functional recovery of the patients were assessed using the appropriate variables.

RESULTS

A total of 104 patients who successfully completed the treatment protocol were assessed. The standardized D3-D4 lymph node dissection harvested sufficient lymph nodes (34.4±7.2) for a precise pathologic staging. Based on histopathological analysis, 28 patients were included in the N3-N4 nodal metastasis-negative group and 33, 34, and nine patients in the single-station, double-station, and triple-station nodal metastasis-positive groups, respectively. Survival analysis indicated no significant difference between the single-station nodal metastasis-positive and N3-N4 nodal metastasis-negative groups in the estimated 5-year survival rate [53.6% (95% CI: 0.3353-0.7000) vs. 71.18% (95% CI: 0.4863-0.8518), P=0.563], whereas patients with double-station or triple-station nodal metastatic disease had poor 5-year survival rates (24.76 and 22.22%), which were comparable to those of AJCC/UICC stage IV disease than those with single-station metastasis-positive disease. Univariate analysis showed that the metastatic status of the five nodal stations was comparable in predicting the overall survival; in contrast, multivariate analysis indicated that common iliac vessels and infra-renal vein were the only two statistically significant predictors (P<0.05) for overall survival.

CONCLUSIONS

Using a robotic approach, D3-D4 lymph node dissection could be safely performed in a standardized manner to remove the relevant N3-N4 lymphatic basin en bloc, thereby providing significant survival benefits and precise pathological staging for patients. This study encourages further international prospective clinical trials to provide more solid evidence that would facilitate the optimization of surgery and revision of the current treatment guidelines for such a clinical conundrum.

Pathologic Complete Response and Long-Term Survival After Preoperative Chemotherapy for Transverse Colon Cancer With Para-Aortic Lymph Node Metastases

A 52-year-old male patient was diagnosed with transverse colon cancer and synchronous stage IVA para-aortic lymph node (PALN) metastases (cT3N1bM1a of the lymph node). Six courses of mFOLFOX6 plus bevacizumab were administered as neoadjuvant chemotherapy. Computed tomography showed shrinkage of the primary tumor and PALN metastases. Extended right hemicolectomy, D3 lymph node dissection, and PALN dissection were performed. A pathologic examination indicated that the tumor had completely changed and comprised necrotic tissue with no viable cells. Therefore, it was considered that mFOLFOX6 plus bevacizumab resulted in a pathologic complete response. Postoperatively, six courses of mFOLFOX6 were administered. Six years postoperatively, the patient did not exhibit any signs of recurrence. There have been few reports of pathologic complete response after neoadjuvant therapy and resection for colon cancer with synchronous PALN metastases. This report describes a unique case involving a pathologic complete response with long-term survival after mFOLFOX6 plus bevacizumab and radical resection, including PALN dissection. Preoperative mFOLFOX6 plus bevacizumab followed by radical resection and adjuvant mFOLFOX6 therapy was safe and resulted in a good outcome. This regimen should be considered for advanced colon cancer with PALN metastases.

Prognostic factors of para-aortic lymph node metastasis from colorectal cancer in highly selected patients undergoing para-aortic lymph node dissection

PURPOSE

We investigated the surgical outcomes of para-aortic lymph node (PALN) dissection in patients with colorectal cancer and assessed the prognostic factors related to the survival.

METHODS

This single-center retrospective study included 31 patients with synchronous or metachronous PALN metastasis from colorectal cancer who underwent PALN dissection between January 2006 and December 2018.

RESULTS

Twenty-one patients had synchronous PALN metastasis, and 10 had metachronous PALN metastasis. Seven patients had either simultaneous distant metastasis or a history of distant metastasis other than PALN metastasis at the time of PALN dissection. Eighteen patients underwent adjuvant chemotherapy. The 5-year overall and recurrence-free survival rates were 54.2 and 17.2%, respectively. A multivariable analysis revealed that rectal cancer, metachronous PALN metastasis, and three or more pathological PALN metastases were significantly poor prognostic factors for the recurrence-free survival. Among patients with rectal cancer, lower rectal cancer and lateral pelvic lymph node metastasis were poor prognostic factors for the overall survival.

CONCLUSION

Curative PALN dissection for PALN metastasis from colorectal cancer is feasible with favorable long-term outcomes. A multidisciplinary approach, including surgery and chemotherapy, is needed for colorectal cancer with PALN metastasis to improve the long-term outcomes.

The management of clinically suspicious para-aortic lymph node metastasis in colorectal cancer: A systematic review

Approximately 1%-2% of patients with colorectal cancer (CRC) develop para-aortic lymph node (PALN) metastases, which are typically considered markers of systemic disease, and are associated with a poor prognosis. The utility of PALN dissection (PALND) in patients with CRC is of ongoing debate and only small-scale retrospective studies have been published on this topic to date. This systematic review aimed to determine the utility of resecting PALN metastases with the primary outcome measure being the difference in survival outcomes following either surgical resection or non-resection of these metastases. A comprehensive systematic search was undertaken to identify all English-language papers on PALND in the PubMed, Medline, and Google Scholar databases. The search results identified a total of 12 eligible studies for analysis. All studies were either retrospective cohort studies or case series. In this systematic review, PALND was found to be associated with a survival benefit when compared to non-resection. Metachronous PALND was found to be associated with better overall survival as compared to synchronous PALND, and the number of PALN metastases (2 or fewer) and a pre-operative carcinoembryonic antigen level of <5 was found to be associated with a better prognosis. No PALND-specific complications were identified in this review. A large-scale prospective study needs to be conducted to definitively determine the utility of PALND. For the present, PALND should be considered within a multidisciplinary approach for patients with CRC, in conjunction with already established treatment regimens.

Survival outcomes after synchronous para-aortic lymph node metastasis in colorectal cancer: A systematic review

BACKGROUND

Synchronous para-aortic lymph node metastasis (PALNM) in colorectal cancer (CRC) is a relatively rare clinical entity. There is a lack of consensus on management of these patients, and the role of para-aortic lymph node dissection (PALND) remains controversial. This systematic review aims to describe the survival outcomes in colorectal cancer with synchronous PALNM when lymph node dissection is performed.

METHODS

A systematic review of Pubmed, Embase and Web of Science databases for PALND in CRC was performed. Studies including patients with synchronous PALNM undergoing resection with curative intent, published from the year 2000 onwards, were included.

RESULTS

Twelve retrospective studies were included. Four studies reported survival outcomes for rectal cancer, two for colon cancer and six as colorectal. Survival outcomes for 356 patients were included. Average 5-year overall survival (OS) was 22.4%, 33.9% and 37.7% in the rectal, colon and colorectal groups respectively. Three year OS in the groups was 53.6%, 46.2% and 65.7%.

CONCLUSION

There remains a lack of quality data to confidently make recommendations regarding the management of synchronous PALNM in colon and rectal cancer cohorts. Retrospective data suggests a benefit in highly selective cohorts and therefore a case-by-case evaluation remains the standard of care.

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.

The Role of Preoperative Imaging in the Detection of Lateral Lymph Node Metastases in Rectal Cancer: A Systematic Review and Diagnostic Test Meta-analysis

BACKGROUND

Different techniques exist for the imaging of lateral lymph nodes in rectal cancer.

OBJECTIVE

This study aimed to compare the diagnostic accuracy of pelvic MRI, 18 F-FDG-PET/CT, and 18 F-FDG-PET/MRI for the identification of lateral lymph node metastases in rectal cancer.

DATA SOURCES

Data sources include PubMed, Embase, Cochrane Library, and Google Scholar.

STUDY SELECTION

All studies evaluating the diagnostic accuracy of pelvic MRI, 18 F-FDG-PET/CT, and 18 F-FDG-PET/MRI for the preoperative detection of lateral lymph node metastasis in patients with rectal cancer were selected.

INTERVENTIONS

The interventions were pelvic MRI, 18 F-FDG-PET/CT, and/or 18 F-FDG-PET/MRI.

MAIN OUTCOME MEASURES

Definitive histopathology was used as a criterion standard.

RESULTS

A total of 20 studies (1,827 patients) were included out of an initial search yielding 7,360 studies. The pooled sensitivity of pelvic MRI was 0.88 (95% CI, 0.85-0.91), of 18 F-FDG-PET/CT was 0.83 (95% CI, 0.80-0.86), and of 18 F-FDG-PET/MRI was 0.72 (95% CI, 0.51-0.87) for the detection of lateral lymph node metastasis. The pooled specificity of pelvic MRI was 0.85 (95% CI, 0.78-0.90), of 18 F-FDG-PET/CT was 0.95 (95% CI, 0.86-0.98), and of 18 F-FDG-PET/MRI was 0.90 (95% CI, 0.78-0.96). The area under the curve was 0.88 (95% CI, 0.85-0.91) for pelvic MRI and was 0.83 (95% CI, 0.80-0.86) for 18 F-FDG-PET/CT.

LIMITATIONS

Heterogeneity in terms of patients' populations, definitions of suspect lateral lymph nodes, and administration of neoadjuvant treatment.

CONCLUSIONS

For the preoperative identification of lateral lymph node metastasis in rectal cancer, this review found compelling evidence that pelvic MRI should constitute the imaging modality of choice. In contrast, to confirm the presence of lateral lymph node metastasis, 18 F-FDG-PET/MRI modalities allow discarding false positive cases because of increased specificity.

PROSPERO REGISTRATION NUMBER

CRD42020200319.

Development and External Validation of a Preoperative Nomogram for Predicting Lateral Pelvic Lymph Node Metastasis in Patients With Advanced Lower Rectal Cancer

Background

The preoperative prediction of lateral pelvic lymph node (LPLN) metastasis is crucial in determining further treatment strategies for advanced lower rectal cancer patients. In this study, we established a nomogram model to preoperatively predict LPLN metastasis and then externally validated the accuracy of this model.

Methods

A total of 287 rectal cancer patients who underwent LPLN dissection were included in this study. Among them, 200 patients from the Peking University First Hospital were included in the development set, and 87 patients from the First Affiliated Hospital of Xi’an Jiaotong University were included in the independent external validation set. Multivariate logistic regression analysis was used to develop the nomogram. The performance of the nomogram was assessed based on its calibration, discrimination, and clinical utility.

Results

Five factors (differentiation grade, extramural vascular invasion, distance of the tumor from the anal verge, perirectal lymph node status, and largest short-axis diameter of LPLN) were identified and included in the nomogram. The nomogram developed based on the analysis showed robust discrimination with an area under the receiver operating characteristic curve (AUC) of 0.878 (95% CI, 0.824–0.932). The validation set showed good discrimination with an AUC of 0.863 (95% CI, 0.779–0.948). Decision curve analysis showed that the nomogram was clinically useful.

Conclusions

The present study proposed a clinical-imaging nomogram with a combination of clinicopathological risk factors and imaging features. After external verification, the predictive power of the nomogram model was satisfactory, and it is expected to be a convenient, visual, and personalized clinical tool for assessing the risk of LPLN metastasis in advanced lower rectal cancer patients.

Is Surgical Treatment Effective or Contraindicated in Patients with Colorectal Cancer Liver Metastases Exhibiting Extrahepatic Metastasis?

BACKGROUND

Surgical resection for patients with hepatic and extrahepatic colorectal metastases remains controversial. This study aimed to determine the efficacy of curative resection of distant extrahepatic metastatic lesions in patients with colorectal liver metastases (CRLM).

METHODS

From 2007 to 2019, 377 patients with CRLM were treated; of these, 323 patients underwent hepatectomy, and 54 patients with extrahepatic metastases (EHM) had received only chemotherapy. Survival and recurrence were compared between patients with and without EHM. Variables potentially associated with survival were analyzed in univariate and multivariate analyses.

RESULTS

Among patients who underwent hepatectomy, the median, 3-, and 5-year overall survival rates for patients with EHM (n = 60) were 32 months, 47%, and 28%, respectively, while those for patients without EHM (n = 263) were 115 months, 79%, and 66%, respectively (p < 0.001). Furthermore, outcomes were similar in R2 patients with EHM and those with unresectable tumors. However, outcomes were significantly better in the R0/1 group than in the R2 and unresectable groups (p < 0.001). Among patients with EHM, multivariate analysis revealed that higher clinical risk score, incomplete resection of all EHM, extrahepatic disease detected intraoperatively, and previous treatment with neoadjuvant chemotherapy were independently associated with worse survival.

CONCLUSIONS

In patients with CRLM with EHM (liver + one organ), gross curative resection is necessary when surgical treatment is contemplated, and resection of liver metastases should be performed in patients with CRLM with smaller and fewer tumors (e.g., H1).

Comparison of postoperative laparoscopic and open total mesorectal excision on lower urinary tract function in men with rectal cancer

OBJECTIVES

This study investigated male voiding dysfunction (VD) or lower urinary tract function in rectal cancer (RC) patients after laparoscopic or open total mesorectal excision with pelvic autonomic nerve preservation (PANP).

METHODS

One hundred and eighty-seven male RC patients admitted between January 2016 and May 2019 were enrolled in this study, 112 of whom underwent laparoscopic total mesorectal excision (LTME) and 75 underwent open total mesorectal excision (OTME). The International Prostatic Symptom Score (IPSS) was compared between the two groups.

RESULTS

The postoperative IPSS in patients with RC was elevated on day 7 and gradually decreased during the first month after surgery. Compared with the OTME group, the IPSS scores decreased less in the LTME group at week 1, and months 1 and 3 postoperatively (6.82 ± 2.13 vs 10.15 ± 3.86, 5.70 ± 2.45 vs 7.21 ± 2.0, and 5.01 ± 2.09 vs 5.75 ± 2.55, respectively; P < 0.05). The VD rate was significantly lower in the LTME group than the OTME group at 1, 2, and 3 weeks postoperatively (21.4% vs 26.8%,13.4% vs 25.3%, and 9.8% vs18.6%, respectively; P < 0.05); however, there was no major difference in the incidence of VD 6 months postoperatively between the two groups (P > 0.05). VD was more frequent in the OTME group than the LTME group 6 months postoperatively, but the difference was not statistically significant (odds ratio = 1.857, 95% CI, 0.964-3.645, P = 0.064).

CONCLUSIONS

LTME may be superior to OTME with respect to PANP of lower urinary tract function in males with RC.

Isolated synchronous Virchow lymph node metastasis of sigmoid cancer: A case report

BACKGROUND

Colorectal cancer (CRC) is one of the most common malignant tumors of the digestive tract. Lymphatic metastases of this tumor are mostly confined to the regional lymph nodes, and distant supraclavicular lymph node metastases are very rare.

CASE SUMMARY

In this report, we describe a patient with sigmoid carcinoma and isolated synchronous supraclavicular lymph node metastases. A 56-year-old male presented with a left cervical mass that was confirmed as a lymph node metastasis from sigmoid cancer by several auxiliary examinations. After 6 cycles of chemotherapy with the 5-fluorouracil, leucovorin and oxaliplatin + cetuximab regimen, the sigmoid colon tumor and Virchow’s lymph node metastasis were significantly smaller than before treatment, and no new metastatic sites were observed. Considering the effects of chemotherapy on quality of life, resection of the primary tumor was performed followed by 4 cycles of chemotherapy with the original chemotherapy regimen. Virchow’s lymph node dissection was selected by mutual consultation between the patient and us. After the second surgery, the patient received capecitabine and cetuximab chemotherapy and did not experience recurrence or metastasis during follow-up.

CONCLUSION

In conclusion, supraclavicular lymph node metastasis without any other solid organ metastasis is a potential metastatic pathway for CRC. In addition, after resection of the primary lesion, postoperative chemotherapy combined with supraclavicular lymph node dissection is feasible for the treatment of patients with CRC and isolated synchronous Virchow’s lymph node metastases.

Lateral pelvic lymph nodes for rectal cancer: A review of diagnosis and management

The current status and future prospects for diagnosis and treatment of lateral pelvic lymph node (LPLN) metastasis of rectal cancer are described in this review. Magnetic resonance imaging (MRI) is recommended for the diagnosis of LPLN metastasis. A LPLN-positive status on MRI is a strong risk factor for metastasis, and evaluation by MRI is important for deciding treatment strategy. LPLN dissection (LPLD) has an advantage of reducing recurrence in the lateral pelvis but also has a disadvantage of complications; therefore, LPLD may not be appropriate for cases that are less likely to have LPLN metastasis. Radiation therapy (RT) and chemoradiation therapy (CRT) have limited effects in cases with suspected LPLN metastasis, but a combination of preoperative CRT and LPLD may improve the treatment outcome. Thus, RT and CRT plus selective LPLD may be a rational strategy to omit unnecessary LPLD and produce a favorable treatment outcome.

Efficacy of positron emission tomography in diagnosis of lateral lymph node metastases in patients with rectal Cancer: a retrospective study

BACKGROUND

The presence of lateral pelvic lymph node (LLN) metastasis is an essential prognostic factor in rectal cancer patients. Thus, preoperative diagnosis of LLN metastasis is clinically important to determine the therapeutic strategy. The aim of this study was to evaluate the efficacy of preoperative positron emission tomography/computed tomography (PET/CT) in the diagnosis of LLN metastasis.

METHODS

Eighty-four patients with rectal cancer who underwent LLN dissection at Osaka University were included in this study. The maximum standardized uptake value (SUV_max) of the primary tumor and LLN were preoperatively calculated using PET/CT. Simultaneously, the short axis of the lymph node was measured using multi-detector row computed tomography (MDCT). The presence of metastases was evaluated by postoperative pathological examination.

RESULTS

Of the 84 patients, LLN metastases developed in the left, right, and both LLN regions in 6, 7, and 2 patients, respectively. The diagnosis of the metastases was predicted with a sensitivity of 82%, specificity of 93%, positive predictive value of 58%, negative predictive value of 98%, false positive value of 7%, and false negative value of 18% when the cutoff value of the LLN SUV_max was set at 1.5. The cutoff value of the short axis set at 7 mm on MDCT was most useful in diagnosing LLN metastases, but SUV_max was even more useful in terms of specificity.

CONCLUSIONS

The cutoff value of 1.5 for lymph node SUV_max in PET is a reasonable measure to predict the risk of preoperative LLN metastases in rectal cancer patients.

Prevalence of Metastatic Lateral Lymph Nodes in Asian Patients with Lateral Lymph Node Dissection for Rectal Cancer: A Meta-analysis

Importance

Rectal cancers occupy the eighth position worldwide for new cases and deaths for both men and women. These cancers have a high tendency to form metastases in the mesorectum but also in the lateral lymph nodes. The therapeutic approach for the involved lateral lymph nodes remains controversial.

Objective

We performed a systematic review and meta-analysis to assess the prevalence of metastatic lateral lymph nodes in patients with lateral lymph node dissection (LLND) for rectal cancer, which seems to be a fundamental and necessary criterion to discuss any possible indications for LLND.

Methods

Data sources–study selection–data extraction and synthesis–main outcome and measures. We searched MEDLINE, EMBASE and COCHRANE from November 1, 2018, to November 19, 2018, for studies reporting the presence of metastatic lateral lymph nodes (iliac, obturator and middle sacral nodes) among patients undergoing rectal surgery with LLND. Pooled prevalence values were obtained by random effects models, and the robustness was tested by leave-one-out sensitivity analyses. Heterogeneity was assessed using the Q-test, quantified based on the I2 value and explored by subgroup analyses.

Results

Our final analysis included 31 studies from Asian countries, comprising 7599 patients. The pooled prevalence of metastatic lateral lymph nodes was 17.3% (95% CI: 14.6–20.5). The inter-study variability (heterogeneity) was high (I² = 89%). The pooled prevalence was, however, robust and varied between 16.6% and 17.9% according to leave-one-out sensitivity analysis. The pooled prevalence of metastatic lymph nodes was not significantly different when pooling only studies including patients who received neoadjuvant treatment or those without neoadjuvant treatment (p = 0.44). Meta-regression showed that the pooled prevalence was associated with the sample size of studies (p < 0.05), as the prevalence decreased when the sample size increased.

Conclusion

The pooled prevalence of metastatic lateral lymph nodes was 17.3% among patients who underwent rectal surgery with LLND in Asian countries. Further studies are necessary to determine whether this finding could impact the therapeutic strategy (total mesorectal excision with LLND versus total mesorectal excision with neoadjuvant radiochemotherapy).

Supplementary Information

The online version contains supplementary material available at(10.1007/s00268-021-05956-1)

Metachronous metastasis confined to isolated lymph node after curative treatment of colorectal cancer

BACKGROUND

The incidence of lymph node metastasis (LNM) in colorectal cancer is known to be 2-6%, but little data are available regarding metachronous metastasis confined to isolated LN. The aim of this study is to determine the distribution of isolated LNM and the risk factors for survival of isolated LNM in colorectal cancer.

METHODS

We retrospectively reviewed consecutive patients with colorectal adenocarcinoma between January 2008 and December 2015 at a tertiary referral center. A total of 5902 patients with biopsy-proven colorectal adenocarcinoma treated via surgery were included. Multivariate Cox proportional hazards analysis was used to identify prognostic factors for overall survival.

RESULTS

Of the 5902 patients, recurrent cases were 1326. Among the relapsed patients, 301 patients had isolated LNM (22.69%). Para-aortic (48.8%), pelvic (29.9%), and Lung hilum (10.0%) were the most common sites of isolated LNM; there were statistically significant differences in the distribution of isolated LNM between the colon and rectal cancer (p = 0.02). Approximately 80% of isolated LNM were diagnosed within 3 years. Multidisciplinary therapy for LNM, diagnosis time to LNM, the T-stage, and histological type of primary cancer were identified as independent prognostic factors for overall survival.

CONCLUSION

This study suggests that multidisciplinary management is a potentially effective treatment strategy for isolated LNM. Since time to LNM, the T-stage, and histological type are prognostic factors, an active follow-up program for colorectal cancer is required.

Controversies in the Management of Lateral Pelvic Lymph Nodes in Patients With Advanced Rectal Cancer: East or West?

The presence of lateral pelvic lymph nodes (LPLN) in advanced rectal cancer entails challenges with ongoing debate regarding the role of prophylactic dissection vs. neoadjuvant radiation treatment. This article highlights the most recent data of both approaches: bilateral LPLN dissection in every patient with low rectal cancer (Rb) as per the Japanese guidelines, vs. the developing approach of neoadjuvant radiotherapy as per Eastern countries. In addition, we also accentuate the importance of a combined approach published by Sammour et al. where a simple "one-size-fits-all" strategy should be abandoned. Rectal cancer treatment is well-established in Western countries. Patients with advanced rectal cancer will undergo radiation ± chemo neoadjuvant therapy followed by TME. In the Dutch TME trial, TME plus radiotherapy showed that the presacral area was the most frequent site of recurrence and not the lateral pelvic wall. Supporting this data, the Swedish study also concluded that LPLN metastasis is not an important cause of local recurrence in patients with low rectal cancer. Therefore, Western approach is CRM-orientated and prophylactic LPLN dissection is not performed routinely as the NCCN guideline does not recommend its surgical removal unless metastases are clinically suspicious. The paradigm in Eastern countries differs somewhat. The Korean study demonstrated that adjuvant radiotherapy without lateral lymph node dissection was not enough to control local recurrence and LPLN metastases. The Japanese Trial JCOG 0212 demonstrated the effects of LPLN dissection in reducing local recurrence in the lateral pelvic compartment. We agree with Sammour and Chang on the fact that rather than a mutual exclusivity approach, we should claim for an approach where all available modalities are considered and used to optimize treatment outcomes, classifying patients into 3 categories of LPLN: low risk cT1/T2/earlyT3 (and Ra) with clinically negative LPLN on MRI; Moderate risk (cT3+/T4 with negative LPLN on MRI) and high risk (clinically abnormal LPLN on MRI). Treatment modality should be based on detailed pretreatment workup and an individualized approach that considers all options to optimize the treatment of patients with rectal cancer in the West or the East.

Japanese Society for Cancer of the Colon and Rectum (JSCCR) guidelines 2019 for the treatment of colorectal cancer

The number of deaths from colorectal cancer in Japan continues to increase. Colorectal cancer deaths exceeded 50,000 in 2016. In the 2019 edition, revision of all aspects of treatments was performed, with corrections and additions made based on knowledge acquired since the 2016 version (drug therapy) and the 2014 version (other treatments). The Japanese Society for Cancer of the Colon and Rectum guidelines 2019 for the treatment of colorectal cancer (JSCCR guidelines 2019) have been prepared to show standard treatment strategies for colorectal cancer, to eliminate disparities among institutions in terms of treatment, to eliminate unnecessary treatment and insufficient treatment and to deepen mutual understanding between healthcare professionals and patients by making these guidelines available to the general public. These guidelines have been prepared by consensuses reached by the JSCCR Guideline Committee, based on a careful review of the evidence retrieved by literature searches and in view of the medical health insurance system and actual clinical practice settings in Japan. Therefore, these guidelines can be used as a tool for treating colorectal cancer in actual clinical practice settings. More specifically, they can be used as a guide to obtaining informed consent from patients and choosing the method of treatment for each patient. Controversial issues were selected as clinical questions, and recommendations were made. Each recommendation is accompanied by a classification of the evidence and a classification of recommendation categories based on the consensus reached by the Guideline Committee members. Here, we present the English version of the JSCCR guidelines 2019.

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

BACKGROUND

Lateral lymph node dissection has been 1 of the standard treatments for mid and ow rectal cancer in Japan. The aim of this ad-hoc analysis was to evaluate the impact of lateral lymph node dissection on outcomes in the randomized clinical trial, referred to as the Adjuvant Chemotherapy for Stage II/III Rectal Cancer trial.

METHODS

The Adjuvant Chemotherapy for Stage II/III Rectal Cancer trial was a randomized, phase III trial of adjuvant chemotherapy of 2 different oral fluoropyrimidines; 445 patients with lower rectal cancer were studied in this ad-hoc analysis out of 959 patients in total, 215 of whom underwent lateral lymph node dissection and 230 did not.

RESULTS

There were no significant differences in background characteristics of the patients in the group, except for in age and number of dissected lymph nodes, between the lateral lymph node dissection and without lateral lymph node dissection groups. The age of the younger patients was often used to select candidates for lateral lymph node dissection (lateral lymph node dissection versus non-lateral lymph node dissection; 63.5 ± 8.9 vs 60.7 ± 9.4 [P = .0017]). Lateral lymph node dissection had no impact on relapse-free survival (hazard ratio = 0.941, 95% confidence interval: 0.696-1.271) or overall survival (hazard ratio = 0.858, 95% confidence interval: 0.601-1.224) in all patients with mid and low rectal cancer. In subset analysis, lateral lymph node dissection improved relapse-free survival in female patients and in patients with stage B/C or N3/4 disease. For cumulative recurrence across all patients, the proportion of patients with distant recurrence was slightly greater in the lateral lymph node dissection group but there was no difference in local recurrence.

CONCLUSION

This exploratory analysis did not show that lateral lymph node dissection improves relapse-free survival and overall survival in patients with mid and low rectal cancer. Lateral lymph node dissection may, however, have a prognostic impact on patients with highly invasive rectal cancer.

Feasibility of Extended Dissection of Lateral Pelvic Lymph Nodes During Laparoscopic Total Mesorectal Excision in Patients with Locally Advanced Lower Rectal Cancer: A Single-Center Pilot Study After Neoadjuvant Chemotherapy

BACKGROUND The feasibility of additional dissection of the lateral pelvic lymph nodes (LPLNs) in patients undergoing total mesorectal excision (TME) combined with neoadjuvant chemotherapy (NAC) for locally advanced rectal cancer (LARC) is controversial. The use of laparoscopic surgery is also debated. In the present study, we evaluated the utility of laparoscopic dissection of LPLNs during TME for patients with LARC and metastatic LPLNs after NAC, based on our experience with 19 cases. MATERIAL AND METHODS Twenty-five patients with LARC with swollen LPLNs who underwent laparoscopic TME and LPLN dissection were enrolled in this pilot study. The patients were divided into 2 groups: those patients with NAC (n=19) and without NAC (n=6). Our NAC regimen involved 4 to 6 courses of FOLFOX plus panitumumab, cetuximab, or bevacizumab. RESULTS The operative duration was significantly longer in the NAC group than in the non-NAC group (648 vs. 558 minutes, respectively; P=0.022). The rate of major complications, defined as grade ≥3 according to the Clavien-Dindo classification, was similar between the 2 groups (15.8% vs. 33.3%, respectively; P=0.4016). No conversion to conventional laparotomy occurred in either group. In the NAC group, a histopathological complete response was obtained in 2 patients (10.5%), and a nearly complete response (Tis N0 M0) was observed in one patient (5.3%). Although the operation time was prolonged in the NAC group, the other perioperative factors showed no differences between the 2 groups. CONCLUSIONS Laparoscopic LPLN dissection is feasible in patients with LARC and clinically swollen LPLNs, even after NAC.

Incidence and Predictive Model for Lateral Pelvic Lymph Node Metastasis in Lower Rectal Cancer

The lateral pelvic lymph node recurrence after curative resection in rectal cancer has been reported in more than 20% of cases and the lateral pelvic lymph node (LPLN) metastasis is an independent risk factor for local recurrence. A prospective cohort study with diagnosis of lower rectal cancer stages II and III performed to identify the factors with significant correlation with LPLN metastasis was categorised based on the number of positive factors and proposed a risk stratification model to uncover a possible benefit of LPLD in specific patient subgroups. Forty-three patients with lower rectal cancer underwent curative surgery, total mesorectal excision with bilateral lateral pelvic lymph node dissection. Pre-operative, female gender, raised serum CEA (> 5 ng/mL), cT4, enlarged mesorectal lymph nodes, borderline enlarged LPLN on MRI, lower location (< 5 cm from anal verge), large size (> 5 cm) and non-circumferential lesion were significant predictors for LPLN metastasis. Histopathological, higher tumour grade, higher pT and pN stage, and the presence of LVI were significant factors. On cox-proportional hazard model analysis, female gender, large tumour, cT4, enlarged mesorectal lymph nodes, borderline enlarged LPLN, pN1 and positive LVI were associated with significant hazard. In conclusion, a specific group of patients with lower rectal cancer of stages II and III might be have treated with LPND in spite of concurrent chemo-radiation to achieve satisfactory oncological outcome. The proposed stratification grouping is strongly guiding the patient for lateral pelvic lymph node dissection. Further study to prove the oncological advantage of LPND is warranted at large scale.

Preoperative chemoradiotherapy changes the size criterion for predicting lateral lymph node metastasis in lower rectal cancer

PURPOSE

The purpose of this study was to identify the size criteria of lateral lymph node metastasis in lower rectal cancer both in patients who underwent preoperative CRT and those who did not.

METHODS

This study enrolled 150 patients who underwent resection for primary lower rectal adenocarcinoma with lateral lymph node dissection between 2013 and 2015. Patients were divided into two groups: the CRT group, treated with preoperative chemoradiotherapy before surgery, and the non-CRT group, treated with surgery alone. The short-axis diameter of each dissected lateral lymph node was measured. Receiver-operating characteristic curves were generated to reveal the optimal cutoff values for determining lateral lymph node metastasis in both groups.

RESULTS

In the non-CRT group (n = 131), the ROC curve demonstrated that the optimal cutoff value for determining metastasis was 6.0 mm, with a sensitivity of 78.5% and specificity of 82.9%, and the AUC was 0.845. In comparison, in the CRT group (n = 19), the optimal cutoff value was 5.0 mm, with a sensitivity of 71.4% and specificity of 85.3% and an AUC of 0.836.

CONCLUSION

The cutoff size for determining lateral lymph node metastasis was smaller in the CRT group than in the non-CRT group.

Prophylactic lateral pelvic lymph node dissection in stage IV low rectal cancer

AIM

To assess the clinical significance of prophylactic lateral pelvic lymph node dissection (LPLND) in stage IV low rectal cancer.

METHODS

We selected 71 consecutive stage IV low rectal cancer patients who underwent primary tumor resection, and enrolled 50 of these 71 patients without clinical LPLN metastasis. The patients had distant metastasis such as liver, lung, peritoneum, and paraaortic LN. Clinical LPLN metastasis was defined as LN with a maximum diameter of 10 mm or more on preoperative pelvic computed tomography scan. All patients underwent primary tumor resection, 27 patients underwent total mesorectal excision (TME) with LPLND (LPLND group), and 23 patients underwent only TME (TME group). Bilateral LPLND was performed simultaneously with primary tumor resection in LPLND group. R0 resection of both primary and metastatic sites was achieved in 20 of 50 patients. We evaluated possible prognostic factors for 5-year overall survival (OS), and compared 5-year cumulative local recurrence between the LPLND and TME groups.

RESULTS

For OS, univariate analyses revealed no significant benefit in the LPLND compared with the TME group (28.7% vs 17.0%, P = 0.523); multivariate analysis revealed that R0 resection was an independent prognostic factor. Regarding cumulative local recurrence, the LPLND group showed no significant benefit compared with TME group (21.4% vs 14.8%, P = 0.833).

CONCLUSION

Prophylactic LPLND shows no oncological benefits in patients with Stage IV low rectal cancer without clinical LPLN metastasis.

Prediction of lateral pelvic lymph node metastasis from lower rectal cancer using magnetic resonance imaging and risk factors for metastasis: Multicenter study of the Lymph Node Committee of the Japanese Society for Cancer of the Colon and Rectum

PURPOSE

The goal of the study was to examine prediction of lateral pelvic lymph node (LPLN) metastasis from lower rectal cancer using a logistic model including risk factors for LPLN metastasis and magnetic resonance imaging (MRI) clinical LPLN (cLPLN) status, compared to prediction based on MRI alone.

METHODS

The subjects were 272 patients with lower rectal cancer who underwent MRI prior to mesorectal excision combined with LPLN dissection (LPLD) at six institutes. No patients received neoadjuvant therapy. Prediction models for right and left pathological LPLN (pLPLN) metastasis were developed using cLPLN status, histopathological grade, and perirectal lymph node (PRLN) status. For evaluation, data for patients with left LPLD were substituted into the right-side equation and vice versa.

RESULTS

Left LPLN metastasis was predicted using the right-side model with accuracy of 86.5%, sensitivity 56.4%, specificity 92.7%, positive predictive value (PPV) 61.1%, and negative predictive value (NPV) 91.2%, while these data using MRI cLPLN status alone were 80.4, 76.9, 81.2, 45.5, and 94.5%, respectively. Similarly, right LPLN metastasis was predicted using the left-side equation with accuracy of 83.8%, sensitivity 57.8%, specificity 90.4%, PPV 60.5%, and NPV 89.4%, and the equivalent data using MRI alone were 78.4, 68.9, 80.8, 47.7, and 91.1%, respectively. The AUCs for the right- and left-side equations were significantly higher than the equivalent AUCs for MRI cLPLN status alone.

CONCLUSIONS

A logistic model including risk factors for LPLN metastasis and MRI findings had significantly better performance for prediction of LPLN metastasis compared with a model based on MRI findings alone.

Long-term outcomes after resection of para-aortic lymph node metastasis from left-sided colon and rectal cancer

PURPOSE

Para-aortic lymph node (PALN) metastasis from colorectal cancer is rare and often not suitable for surgery. However, in selected patients, radical resection may bring about longer survival. The aim of this study was to evaluate long-term outcomes of resection of left-sided colon or rectal cancer with simultaneous PALN metastasis.

METHODS

The study included 2122 patients with left-sided colon or rectal cancer (30 patients with and 2092 patients without PALN metastasis) who underwent resection with curative intent between 2002 and 2013. Clinicopathological characteristics, long-term outcomes of resection, and factors related to poor postoperative survival in patients with PALN metastasis were investigated.

RESULTS

Of a total of 2122 total patients, 16 of 50 patients (32.0%) with lymph node metastasis at the root of the inferior mesenteric artery had PALN metastasis. The 5-year overall survival rates for 18 patients who underwent R0 resection and 12 patients who did not were 29.1 and 10.4%, respectively (p = 0.017). Factors associated with poor postoperative survival among patients who underwent R0 resection were presence of conversion therapy, lack of adjuvant chemotherapy, carcinoembryonic antigen >20 ng/mL, and lateral lymph node metastasis in rectal cancer patients. The 5-year recurrence-free survival rate was 14.8%.

CONCLUSIONS

Although recurrence was frequent, R0 resection for left-sided colon or rectal cancer with PALN metastasis was associated with longer survival than R1/R2 resection. Furthermore, the 5-year overall survival rate in the R0 group was relatively favorable for stage IV. Therefore, R0 resection may prolong survival compared with chemotherapy alone in selected patients.

Impact of Lateral Pelvic Lymph Node Dissection on the Survival of Patients with T3 and T4 Low Rectal Cancer

BACKGROUND

The aim of this study was to clarify the survival benefit of lateral pelvic lymph node dissection (LPLND) for patients with pathological T3 and T4 (pT3/T4) low rectal cancer.

METHODS

We evaluated the impact of LPLND on survival for pT3/T4 low rectal cancer patients. The primary endpoint of the study was overall survival (OS). The large-scale database of the Japanese Society for Cancer of the Colon and Rectum registration system was accessed and the data were analyzed using a propensity score matching method based on the likelihood of receiving LPLND. Using seven covariates, the propensity scores were calculated with multivariate logistic regression. A total of 499 propensity score-matched pairs of patients were selected from the entire cohort of 1,840 patients who had received curative resection for pT3/T4 low rectal cancer between 1995 and 2004.

RESULTS

In the matched cohort, the 5-year OS of the patients who had and had not undergone LPLND were 68.9 and 62.0 %, respectively (p = 0.013; hazard ratio [HR], 0.755; 95 % confidence interval [CI], 0.604-0.944). The 5-year OS of the patients with node-negative disease who had and had not received LPLND differed statistically significantly (5-year OS were 82.1 and 71.4 %, respectively. p = 0.006; HR, 0.579; 95 % CI 0.389-0.862). However, those with node-positive disease did not differ significantly (5-year OS were 55.5 and 53.8 %, respectively. p = 0.415; HR 0.893; 95 % CI 0.681-1.172).

CONCLUSIONS

The impact of LPLND on OS for patients with node-negative pT3/T4 low rectal cancer was suggested in this retrospective cohort study. To determine true benefits and harms of LPLND, further prospective studies may be warranted.

Management of para-aortic lymph node metastasis in colorectal patients: A systemic review

INTRODUCTION

Para-aortic lymph node (PALN) involvement occurs in up to 2% of colorectal cancer (CRC) patients. While resection for isolated hepatic and pulmonary metastases in colorectal cancer is standard practice, the role of PALN dissection (PALND) in CRC has not been established and remains a controversy. We aim to perform a systematic review of the literature to determine if extensive lymphadenectomy improves survival, and is an acceptable strategy for PALN metastasis (PALNM).

MATERIALS AND METHODS

A systematic search of PubMed and Embase databases for studies reporting on patients with isolated PALNM in CRC was performed. Studies including patients with synchronous and metachronous PALN were included, and studies including patients with other metastases were excluded.

RESULTS

Eighteen retrospective, single-centre studies were included in the final analysis. The reported incidence of isolated PALNM ranged from 1.3 to 1.7%. A total of 370 patients with PALNM were evaluated, of which 145 had synchronous, and 225 had metachronous PALNM. For synchronous PALNM, the 5-year overall survival (OS) after metastatectomy, ranged from 22.7% to 33.9%. For metachronous PALNM, the 5-year OS ranged from 15 to 60%; median OS was 34-40 months in the PALND versus 3-14 months for patients who did not undergo PALND. There were no reported surgery related mortalities, and overall surgical morbidity was 7.8-33%.

CONCLUSION

PALND for isolated PALNM from colorectal cancer can be performed with minimal morbidity and confers a survival advantage, in comparison with conventional palliative chemotherapy or chemoradiation therapy.

Oncologic Outcomes of Colon Cancer Patients with Extraregional Lymph Node Metastasis: Comparison of Isolated Paraaortic Lymph Node Metastasis with Resectable Liver Metastasis

BACKGROUND

The treatment strategy and benefit of extended lymph node dissection among patients with preoperatively diagnosed paraaortic lymph node metastasis (PALNM) in colon cancer remains highly controversial. In the current study, we analyzed the oncologic outcomes of patients who underwent extraregional lymph node dissection for colon cancer with isolated PALNM.

METHODS

From March 2000 to December 2009, the study group included 1082 patients who underwent curative surgery for colonic adenocarcinoma with pathological lymph node metastasis.

RESULTS

Of 1082 patients who underwent curative surgery for colonic carcinoma, 953 (88.1 %) patients underwent regional lymphadenectomy, and 129 (11.9 %) patients underwent paraaortic lymph node dissection. Pathologic examination revealed N1 stage disease in 738 (68.2 %), N2 in 295 (27.3 %), and PALNM in 49 (4.5 %). Five-year overall survival (OS) and disease-free survival (DFS) rate were significantly better in the regional LNM group than in the PALNM group (OS 75.1 vs. 33.9 %, p < 0.001; DFS 66.2 vs. 26.5 %, p < 0.001). Five-year OS and DFS were not significantly different between the PALNM and resectable liver metastasis patients who underwent curative resection (OS 33.9 vs. 38.7 %, p = 0.080; DFS 26.5 vs. 27.6 %, p = 0.604).

CONCLUSIONS

PALNM in colon cancer is associated with poorer survival than regional lymph node metastasis and showed comparable survival rates with metastasectomy for liver metastasis. Further studies evaluating the net benefit of upfront chemotherapy compared with initial resection for patients with potentially resectable PALNM are needed.

Selection of Lymph Node-Positive Cases Based on Perirectal and Lateral Pelvic Lymph Nodes Using Magnetic Resonance Imaging: Study of the Japanese Society for Cancer of the Colon and Rectum

PURPOSE

To investigate the optimum cutoff for lymph node size to identify cases positive for perirectal lymph node (PRLN) and lateral lymph node (LPLN) metastasis of lower rectal cancer on magnetic resonance imaging (MRI).

METHODS

The subjects were 449 patients who underwent preoperative MRI. Mesorectal excision was performed in all patients (combined with lateral pelvic lymph node [LN] dissection in 324) between 2004 and 2013 at 6 institutes. Cases were classified as cN positive and cN negative on the basis of the short axis of the largest LN being greater than or equal to a cutoff or less than a cutoff, respectively. PRLN and LPLN diagnoses using 5 and 10 mm cutoffs were compared with histologic diagnoses. Of the 449 patients, 55 received preoperative chemoradiotherapy. MRI was only performed after this therapy in all of these patients.

RESULTS

For PRLNs, 5 and 10 mm cutoffs gave area under the curve (AUC) values of 0.6364 and 0.5794, respectively. The 5 mm cutoff gave a significantly higher AUC value (P = 0.0152), with an accuracy of 63.7 %, sensitivity of 72.6 %, and specificity of 54.7 %. For right LPLNs, the respective AUC values were 0.7418 and 0.6326 (P = 0.0034), and the variables (5 mm cutoff) were 77.6, 68.6, and 79.7 %. For left LPLNs, AUC values were 0.7593 and 0.6559, respectively (P = 0.0057), and the variables (5 mm cutoff) were 79.3, 70.8, and 81.0 %.

CONCLUSIONS

Identification of LN-positive cases on the basis of PRLN and LPLN sizes was superior at a short-axis 5 mm cutoff. Size-based diagnosis of LN metastasis is simple and useful, but further investigation is needed to clarify whether it is superior to diagnosis based on morphology, such as shape, border, and signal intensity.

Successful resection of metachronous para-aortic, Virchow lymph node and liver metastatic recurrence of rectal cancer

A 66-year-old female presented with the main complaint of defecation trouble and abdominal distention. With diagnosis of rectal cancer, cSS, cN0, cH0, cP0, cM0 cStage II, Hartmann’s operation with D3 lymph node dissection was performed and a para-aortic lymph node and a disseminated node near the primary tumor were resected. Histological examination showed moderately differentiated adenocarcinoma, pSS, pN3, pH0, pP1, pM1 (para-aortic lymph node, dissemination) fStage IV. After the operation, the patient received chemotherapy with FOLFIRI regimen. After 12 cycles of FOLFIRI regimen, computed tomography (CT) detected an 11 mm of liver metastasis in the postero-inferior segment of right hepatic lobe. With diagnosis of liver metastatic recurrence, we performed partial hepatectomy. Histological examination revealed moderately differentiated adenocarcinoma as a metastatic rectal cancer with cut end microscopically positive. After the second operation, the patient received chemotherapy with TS1 alone for 2 years. Ten months after the break, CT detected a 20 mm of para-aortic lymph node metastasis and a 10 mm of lymph node metastasis at the hepato-duodenal ligament. With diagnosis of lymph node metastatic recurrences, we performed lymph node dissection. Histological examination revealed moderately differentiated adenocarcinoma as metastatic rectal cancer in para-aortic and hepato-duodenal ligament areas. After the third operation, we started chemotherapy with modified FOLFOX6 regimen. After 2 cycles of modified FOLFOX6 regimen, due to the onset of neutropenia and liver dysfunction, we switched to capecitabine alone and continued it for 6 mo and then stopped. Eleven months after the break, CT detected two swelling 12 mm of lymph nodes at the left supraclavicular region. With diagnosis of Virchow lymph node metastatic recurrence, we started chemotherapy with capecitabine plus bevacizumab regimen. Due to the onset of neutropenia and hand foot syndrome (Grade 3), we managed to continue capecitabine administration with extension of interval period and dose reduction. After 2 years and 2 mo from starting capecitabine plus bevacizumab regimen, Virchow lymph nodes had slowly grown up to 17 mm. Because no recurrence had been detected besides Virchow lymph nodes for this follow up period, considering the side effects and quality of life, surgical resection was selected. We performed left supraclavicular lymph node dissection. Histological examination revealed moderately differentiated adenocarcinoma as a metastatic rectal cancer. After the fourth operation, the patient selected follow up without chemotherapy. Now we follow up her without recurrence and keep her quality of life high.

The significance of extended lymphadenectomy for colorectal cancer with isolated synchronous extraregional lymph node metastasis

BACKGROUND/OBJECTIVE

The significance of extended lymphadenectomy for colorectal cancer with extraregional lymph node metastasis, such as para-aortic lymph node metastasis, has not been established. The purpose of this study was to evaluate the significance of extended lymphadenectomy for colorectal cancer with synchronous isolated extraregional lymph node metastasis.

METHODS

Between July 2004 and December 2013, 16 patients with synchronous extraregional lymph node metastasis without other organ metastases underwent curative resection and extended lymphadenectomy (R0 group). The clinical characteristics and survival outcomes of the R0 group were compared with those of 12 patients with extraregional lymph node metastasis who underwent palliative surgery (control group).

RESULTS

In the R0 group, the 5-year cancer-specific survival (CSS) rate was 70.3% and the 5-year relapse-free survival (RFS) rate was 60.5%. The 5-year CSS differed significantly between the R0 and control groups (70.3% vs. 12.5%; p = 0.0003). Univariate analyses revealed that the total numbers of metastatic lymph nodes and metastatic regional lymph nodes present were significantly associated with RFS (p = 0.019 for both).

CONCLUSION

Findings from our study suggest that extended lymphadenectomy for colorectal cancer with synchronous isolated extraregional lymph node metastasis might be effective in carefully selected patients.

The Prognostic Role of Para-Aortic Lymph Nodes in Patients with Colorectal Cancer: Is It Regional or Distant Disease?

Introduction

Visible para-aortic lymph nodes of ≥2 mm in size are common metastatic patterns of colorectal cancer (CRC) seen on imaging. Their prognostic value, however, remains inconclusive. We aimed to assess the prognostic role of visible para-aortic lymph nodes (PALNs).

Methods

Patients with confirmed pathologic diagnosis of CRC were enrolled. Correlations among clinicopathologic variables were analyzed using the χ² test. The Cox proportional hazards model was applied for univariate and multivariate analyses. Survival was estimated using the Kaplan-Meier method and log-rank test. A prognostic model for visible PALNs in CRC patients was established.

Results

In total, 4527 newly diagnosed CRC patients were enrolled. Patients with visible PALNs had inferior overall survival compared to those without visible PALNs (5-year overall survival, 67% vs. 76%, P = 0.015). Lymphovascular invasion (LVI) (hazard ratio = 1.865, P = 0.015); nodal disease (pN+) status (hazard ratio = 2.099, P = 0.006); elevated preoperative serum carcinoembryonic antigen (CEA) levels (hazard ratio = 2.263, P < 0.001); and visible PALNs ≥10 mm (hazard ratio = 1.638, P = 0.031) were independent prognostic factors for patients with visible PALNs. If each prognostic factor scored one point, 5-year overall survival of lower- (prognostic score 0–1), intermediate- (prognostic score 2), and high- (prognostic score 3–4) risk groups were, 78%. 54%, and 25% respectively (P < 0.001).

Conclusions

The prognostic model, which included LVI, pN+ status, preoperative serum CEA level, and the size of visible PALNs, could effectively distinguish the outcome of patients with visible PALNs.

A systematic review of outcome reporting in colorectal cancer surgery

AIM

Evaluation of surgery for colorectal cancer (CRC) is necessary to inform clinical decision-making and healthcare policy. The standards of outcome reporting after CRC surgery have not previously been considered.

METHOD

Systematic literature searches identified randomized and nonrandomized prospective studies reporting clinical outcomes of CRC surgery. Outcomes were listed verbatim, categorized into broad groups (outcome domains) and examined for a definition (an appropriate textual explanation or a supporting citation). Outcome reporting was considered inconsistent if results of the outcome specified in the methods were not reported. Outcome reporting was compared between randomized and nonrandomized studies.

RESULTS

Of 5644 abstracts, 194 articles (34 randomized and 160 nonrandomized studies) were included reporting 766 different clinical outcomes, categorized into seven domains. A mean of 14 ± 8 individual outcomes were reported per study. 'Anastomotic leak', 'overall survival' and 'wound infection' were the three most frequently reported outcomes in 72, 60 and 44 (37.1%, 30.9% and 22.7%) studies, respectively, and no single outcome was reported in every publication. Outcome definitions were significantly more often provided in randomized studies than in nonrandomized studies (19.0% vs 14.9%, P = 0.015). One-hundred and twenty-seven (65.5%) papers reported results of all outcomes specified in the methods (randomized studies, n = 21, 61.5%; nonrandomized studies, n = 106, 66.2%; P = 0.617).

CONCLUSION

Outcome reporting in CRC surgery lacks consistency and method. Improved standards of outcome measurement are recommended to permit data synthesis and transparent cross-study comparisons.

Incidence and prognosis of lower rectal cancer with limited extramesorectal lymph node metastasis

PURPOSE

Patients with lower rectal cancer occasionally have limited extramesorectal lymph node metastasis. However, the incidence and prognosis of lower rectal cancer with limited extramesorectal lymph node metastasis remain unclear.

METHODS

A total of 714 patients with clinical stage II or III lower rectal cancer who underwent extramesorectal lymph node dissection at the National Cancer Center Hospital between 1985 and 2011 were reviewed.

RESULTS

Among the 714 patients with lower rectal cancer, 35 (4.9 %) had limited extramesorectal lymph node metastasis, of whom 28 (80.0 %) had one or two extramesorectal lymph node metastases. The 5-year overall survival rate was 74.5 %. The number of extramesorectal lymph node metastases was a significant prognostic factor. The 5-year overall survival rate of patients with three or more extramesorectal lymph node metastases was 28.6 %.

CONCLUSIONS

The incidence of limited extramesorectal lymph node metastasis in patients with lower rectal cancer was 4.9 %. Although the prognosis of patients with one or two extramesorectal lymph node metastases was favorable, that of patients with three or more such metastases was unfavorable.

Neoadjuvant chemoradiotherapy affects the indications for lateral pelvic node dissection in mid/low rectal cancer with clinically suspected lateral node involvement: a multicenter retrospective cohort study

BACKGROUND

Although lateral pelvic node dissection (LPND) is recommended for rectal cancer with clinically metastatic lateral pelvic lymph nodes (LPNs), LPNs may respond to neoadjuvant chemoradiotherapy (nCRT). Our aim was to determine the optimal indication for LPND after nCRT for mid/low rectal cancer.

METHODS

Of 2,263 patients with clinical stage II/III mid/low rectal cancer who were managed at three tertiary referral hospitals, 66 patients underwent curative surgery including LPND after nCRT were included in this study. Risk factors for LPN metastasis were retrospectively analyzed and oncologic outcomes determined according to LPN response to nCRT.

RESULTS

Persistent LPNs greater than 5 mm on post-nCRT magnetic resonance imaging were significantly associated with residual tumor metastasis, unlike responsive LPN after nCRT (short-axis diameter ≤ 5 mm) (pathologically, 61.1 % [22 of 36] vs. 0 % [0 of 30], P < 0.001). Multivariable analysis revealed post-nCRT LPN size as a significant and independent risk factor for LPN metastasis (odds ratio 2.390; 95 % confidence interval 1.104-4.069). Over a median follow-up of 39.3 months, the recurrence rate was lower in patients with responsive nodes than in patients with persistent nodes (20 % [6 of 30] vs. 47.2 % [17 of 36], P = 0.012). The 5-year overall survival and 5-year disease-free survival rates were lower in patients with persistent LPN than in patients with responsive LPN (44.6 % vs. 77.1 %, P = 0.034; 33.7 % vs. 72.5 %, P = 0.011, respectively).

CONCLUSIONS

In mid/low rectal cancer with clinically metastatic LPNs, the decision to perform LPND should be based on the LPN response to nCRT.

Robotic and laparoscopic pelvic lymph node dissection for rectal cancer: short-term outcomes of 21 consecutive series

PURPOSE

The aim of this study is to describe our initial experience and assess the feasibility and safety of robotic and laparoscopic lateral pelvic node dissection (LPND) in advanced rectal cancer.

METHODS

Between November 2007 and November 2012, extended minimally invasive surgery for LPND was performed in 21 selected patients with advanced rectal cancer, including 11 patients who underwent robotic LPND and 10 who underwent laparoscopic LPND. Extended lymphadenectomy was performed when LPN metastasis was suspected on preoperative magnetic resonance imaging even after chemoradiation.

RESULTS

All 21 procedures were technically successful without the need for conversion to open surgery. The median operation time was 396 minutes (range, 170-581 minutes) and estimated blood loss was 200 mL (range, 50-700 mL). The median length of stay was 10 days (range, 5-24 days) and time to removal of the urinary catheter was 3 days (range, 1-21 days). The median total number of lymph nodes harvested was 24 (range, 8-43), and total number of lateral pelvic lymph nodes was 7 (range, 2-23). Six patients (28.6%) developed postoperative complications; three with an anastomotic leakages, two with ileus and one patient with chyle leakage. Two patients (9.5%) developed urinary incontinence. There was no mortality within 30 days. During a median follow-up of 14 months, two patients developed lung metastasis and there was no local recurrence.

CONCLUSION

Robotic and laparoscopic LPND is technically feasible and safe. Minimally invasive techniques for LPND in selected patients can be an acceptable alternative to an open LPND.

Intra-operative tumour detection and staging in colorectal cancer surgery

AIM

Surgical resection for colorectal cancer involves segmental resection and regional lymphadenectomy. The appropriateness of this 'one-size-fits-all' strategy is questioned as bowel cancer screening programmes result in a shift to earlier stage disease. Currently, the nodal status of a colorectal cancer can only be reliably determined by histopathological examination of the resected specimen. New methods of intra-operative staging are required to allow surgical resection to be tailored to the stage of the disease.

METHOD

A literature search was performed of PubMed and Embase databases using the terms 'colon' OR 'colorectal' AND 'intra-operative detection' OR 'intra-operative staging' OR 'intra-operative detection' OR 'radioimmunoguided surgery'. Articles published between January 1980 and January 2012 were included. Technologies that have the potential to allow intra-operative staging and treatment stratification were identified and further searches performed.

RESULTS

Established techniques such as sentinel lymph node mapping and radioimmunoguided surgery have benefited from combination with other technologies to allow real-time intra-operative staging. Intra-operative fluorescence, using naturally fluorescent biomarkers or fluorescent tumour probes, probably offers the most practical means of intra-operative lymph node staging and may be facilitated using nanotechnology. Optical coherence tomography and real-time elastography have the potential to provide an in vivo'virtual biopsy'.

CONCLUSION

Technological advances may allow accurate intra-operative lymph node staging to facilitate tailored surgical resection. This may become the next paradigm shift in colorectal cancer surgery.

The role of lateral lymph node dissection in the management of lower rectal cancer

INTRODUCTION

Lateral lymph node involvement is a problem encountered in patients with low rectal cancers. This has been documented in both anatomical and pathological studies. Currently, the vast majority of centers have concentrated on the use of chemoradiation to obtain better local control and manage these nodes indirectly. In Japan, extended nodal dissection for the control of pelvic nodal disease has seen further advancement. This paper discusses the key issues involved in the management of pelvic lateral nodes in low rectal cancers.

METHODS

A review of available literature and critical appraisal of the entity of lateral nodes in low rectal cancers, the treatment options, and oncological and functional results were performed.

RESULTS

There are good data showing that the entity of pelvic lateral nodes in low rectal cancers should not be ignored. Recent data have emerged showing that radiotherapy is associated with significant long-term functional side effects. Refinement of the technique, lateral node dissection, has led to good local control as well as good functional outcomes.

CONCLUSION

In this context, there needs to be a reevaluation of the role of chemoradiation as the sole treatment for lateral nodal disease in centers outside of Japan. Individualization of the treatment of rectal cancer may require all centers to be able to offer both modalities.

EUS-FNA assessment of extramesenteric lymph node status in primary rectal cancer

BACKGROUND

Preoperative staging is an essential factor in the multidisciplinary management of rectal cancer. The accuracy of imaging alone with CT, magnetic resonance imaging, or rigid endorectal US is poor. The addition of EUS-FNA may enhance extramesenteric lymph node metastases detection (M1 disease) and overall staging accuracy.

OBJECTIVE

To evaluate the frequency of extramesenteric lymph node visualization by EUS and the rate of extramesenteric lymph node metastases by FNA. Secondary goals were to evaluate the clinical, endoscopic, and sonographic features associated with extramesenteric lymph node metastases, disease progression, and overall mortality.

DESIGN

Retrospective cohort study.

SETTINGS

Tertiary referral center.

RESULTS

Forty-one of 316 patients (13%) with primary rectal cancer over a 6-year period had M1 disease by EUS-FNA. Significant clinical, endoscopic, and sonographic features associated with extramesenteric lymph node metastases included the serum carcinoembryonic antigen level, tumor length 4 cm and longer, annularity 50% or more, sessile morphology, and lymph node size. The sensitivity and specificity of CT for extramesenteric lymph node metastases were 44% and 89%, respectively. Twenty-three of 316 rectal cancer endosonographic procedures (7.3%) were up-staged by FNA, which established extramesenteric lymph node metastases. Over a 4-year follow-up, disease progression and overall mortality of patients with extramesenteric lymph node metastases was observed in 6 patients (14.6%) and 14 patients (34%), respectively.

CONCLUSIONS

Preoperative EUS-FNA identification of extramesenteric lymph node metastases outside of standard radiation fields or total mesorectal excision resection margins could affect medical and surgical planning.

Clinical impact of lymph node status in rectal cancer

Lymph node status at the time of diagnosis remains one of the principal indicators of prognosis in patients with rectal cancer. Involvement of loco-regional lymph nodes is relevant to surgical and clinical oncologists and continues to impact significantly upon local and systemic management strategies, in both neo-adjuvant and adjuvant settings. In this review, the clinical impact of lymph node status in the surgical management of rectal cancer is considered, with particular reference to the significance of lymphadenectomy and the potential implications for rectal tumours amenable to trans-anal excision. Current standards of care are reviewed and the extent to which the determination of lymph node status influences oncological decisions regarding neo-adjuvant and adjuvant therapies are discussed with areas of controversy highlighted.

Review of histopathological and molecular prognostic features in colorectal cancer

Prediction of prognosis in colorectal cancer is vital for the choice of therapeutic options. Histopathological factors remain paramount in this respect. Factors such as tumor size, histological type and subtype, presence of signet ring morphology and the degree of differentiation as well as the presence of lymphovascular invasion and lymph node involvement are well known factors that influence outcome. Our understanding of these factors has improved in the past few years with factors such as tumor budding, lymphocytic infiltration being recognized as important. Likewise the prognostic significance of resection margins, particularly circumferential margins has been appreciated in the last two decades. A number of molecular and genetic markers such as KRAS, BRAF and microsatellite instability are also important and correlate with histological features in some patients. This review summarizes our current understanding of the main histopathological factors that affect prognosis of colorectal cancer.

Patterns of local recurrence in rectal cancer after a multidisciplinary approach

Improvements in surgery and the application of combined approaches to fight rectal cancer have succeeded in reducing the local recurrence (LR) rate and when there is LR it tends to appear later and less often in isolation. Moreover, a subtle change in the distribution of LRs with respect to the pelvis has been observed. In general terms, prior to total mesorectal excision the most common LRs were central types (perianastomotic and anterior) while lateral and posterior forms (presacral) have become more common since the growth in the use of combined treatments. No differences have been reported in the current pattern of LRs as a function of the type of approach used, that is, neo-adjuvant therapies (short-term or long-course radiotherapy, or chemoradiotherapy versus extended lymphadenectomy, though there is a trend towards posterior or presacral LR in patients in the Western world and lateral LR in Asia. Nevertheless, both may arise from the same mechanism. Moreover, as well as the mode of treatment, the type of LR is related to the height of the initial tumor. Nowadays most LRs are related to the advanced nature of the disease. Involvement of the circumferential radial margin and spillage of residual tumor cells from lymphatic leakage in the pelvic side wall are two plausible mechanisms for the genesis of LR. The patterns of pelvic recurrence itself (pelvic subsites) also have important implications for prognosis and are related to the potential success of salvage curative approach. The re-operability for cure and prognosis are generally better for anastomotic and anterior types than for presacral and lateral recurrences. Overall survival after LR diagnosis is lower with radio or chemoradiotherapy plus optimal surgery approaches, compared to optimal surgery alone.

Prognostic impact of inferior mesenteric artery lymph node metastasis in colorectal cancer

AIM

The aims of this study are to identify the natural course of inferior mesenteric artery (IMA) lymph node metastasis, and to evaluate the prognostic impact of IMA lymph node metastasis in the sigmoid colon and rectal cancer.

PATIENTS AND METHODS

From our prospectively collected database, a total of 625 patients who underwent resection with curative intent for stage III adenocarcinoma of the sigmoid colon and rectal cancer between June 1995 and June 2007 were selected. Patients were divided into the IMA-positive group (n = 33) and the IMA-negative group (n = 592) according to IMA lymph node metastasis status. Clinicopathological features, recurrence patterns, and 5-year disease-free survival rates were compared between the two groups.

RESULTS

Following curative resection, 5-year disease-free survival rate was 31.9% in the IMA-positive group and 69.4% in the IMA-negative group (p < 0.001). Cox regression analysis revealed that rectal cancer, pathologic stage, and presence of IMA lymph node metastasis were independently associated with disease-free survival. Systemic recurrence rate was significantly higher in the IMA-positive group than in the IMA-negative group (48.5 vs. 20.8%, respectively, p = 0.001). Para-aortic nodal recurrence showed significant association with presence of IMA lymph node metastasis on multivariate analysis (hazard ratio 11.8; 95% confidence interval 2.7-52.2, p = 0.001).

CONCLUSION

Presence of IMA lymph node metastasis should be considered as a predictive factor for high systemic recurrence, and should be treated and followed up with caution for para-aortic nodal recurrence.