Prognostic significance of apical lymph node metastasis in patients with node-positive rectal cancer

Correlation study of functional magnetic resonance index and clinicopathological features of rectal cancer

PURPOSE

To investigate the correlation between DCE-MRI, R2*, IVIM, and clinicopathological features of rectal cancer.

METHODS

This was a prospective study, enrolling 42 patients with rectal cancer, 20 of whom underwent rectal mesorectal excision. Dynamic contrast-enhanced magnetic resonance imaging scanning was performed preoperatively in all patients, and additional preoperative scanning of R2* imaging and intravoxel incoherent motion was performed in those who underwent surgery. Artificially delineate the ROI around the tumor. Functional magnetic resonance index parameters Ktrans, Ve, R2*, D, D*, and f were estimated by computer software to analyze postoperative pathological reports of patients undergoing total mesenteric resection. Correlation and significance analyses of imaging metrics and pathologic features were performed by GraphPad Prism 9 to assess statistical significance.

RESULTS

DEC-MRI, R2*, and IVIM have certain application values in the distance from the lower margin of the tumor to the anorectal ring, imaging T stage and N stage, tumor markers CEA and CA199, immunohistochemical indexes Ki-76 and P53, lymph node cancer metastasis, and rectal fascia status (P < 0.05).

CONCLUSION

DEC-MRI, R2*, and IVIM provide reliable quantitative parameters for preoperative clinicopathological evaluation of patients with rectal cancer.

Laparoscopic D3 lymph node dissection with left colic artery and first sigmoid artery preservation in rectal cancer

BACKGROUND

D3 lymph node dissection with left colic artery (LCA) preservation in rectal cancer surgery seems to have little effect on reducing postoperative anastomotic leakage. So we first propose D3 lymph node dissection with LCA and first sigmoid artery (SA) preservation. This novel procedure deserves further study.

METHODS

Rectal cancer patients who underwent laparoscopic D3 lymph node dissection with LCA preservation or with LCA and first SA preservation between January 2017 and January 2020 were retrospectively assessed. The patients were categorized into two groups: the preservation of the LCA group and the preservation of the LCA and first SA group. A 1:1 propensity score-matched analysis was performed to decrease confounding.

RESULTS

Propensity score matching yielded 56 patients in each group from the eligible patients. The rate of postoperative anastomotic leakage in the preservation of the LCA and first SA group was significantly lower than that in the LCA preservation group (7.1% vs. 0%, P=0.040). No significant differences were observed in operation time, length of hospital stay, estimated blood loss, length of distal margin, lymph node retrieval, apical lymph node retrieval, and complications. A survival analysis showed patients' 3-year disease-free survival (DFS) rates of group 1 and group 2 were 81.8% and 83.5% (P=0.595), respectively.

CONCLUSION

D3 lymph node dissection with LCA and first SA preservation for rectal cancer may help reduce the incidence of anastomotic leakage without compromising oncological outcomes compare with D3 lymph node dissection with LCA preservation alone.

High Versus Low Ligation of the Inferior Mesenteric Artery in Colorectal Cancer Surgery: A Systematic Review and Meta-Analysis

Background and Objectives: This study aimed to compare the effects of high ligation (HL) versus low ligation (LL) in colorectal cancer surgery. Materials and Methods: We performed a comprehensive search using multiple databases (trial registries and ClinicalTrials.gov), other sources of grey literature, and conference proceedings, with no restrictions on the language or publication status, up until 10 March 2021. We included all parallel-group randomized controlled trials (RCTs) and considered cluster RCTs for inclusion. The risk of bias domains were "low risk," "high risk," or "unclear risk." We performed statistical analyses using a random-effects model and interpreted the results according to the Cochrane Handbook for Systematic Reviews of Interventions. We used the GRADE guidelines to rate the certainty of evidence (CoE) of the randomized controlled trials. Results: We found 12 studies (24 articles) from our search. We were very uncertain about the effects of HL on overall mortality, disease recurrence, cancer-specific mortality, postoperative mortality, and anastomotic leakage (very low CoE). There may be little to no difference between HL and LL in postoperative complications (low CoE). For short-term follow-up (within 6 months), HL may reduce defecatory function (constipation; low CoE). While HL and LL may have similar effects on sexual function in men, HL may reduce female sexual function compared with LL (low CoE). For long-term follow-up (beyond 6 months), HL may reduce defecatory function (constipation; low CoE). There were discrepancies in the effects regarding urinary dysfunction according to which questionnaire was used in the studies. HL may reduce male and female sexual function (low CoE). Conclusions: We are very uncertain about the effects of HL on survival outcomes, and there is no difference in the incidence of postoperative complications between HL and LL. More rigorous RCTs are necessary to evaluate the effect of HL and LL on functional outcomes.

The prognostic significance of apical lymph node metastasis in patients with high-risk stage III colon cancer

The effect of apical lymph node (APN) metastasis on the prognosis of colon cancer is unknown. The present study investigated the impact of APN metastasis on the prognosis of the patients with high-risk stage III colon cancer. This retrospective multi-institutional study included patients with pathological high-risk stage III colon cancer who underwent surgery between April 2009 and December 2014. Clinicopathological factors were examined by univariate and multivariate analyses to clarify independent risk factors for overall survival (OS) and relapse-free survival (RFS). A total of 185 patients were collected. The 5-year OS rates of patients with and without APN metastasis were 35.0% and 72.1%, respectively (p = 0.0014). The 5-year RFS rates of patients with and without APN metastasis was 16.2% and 57.2%, respectively (p = 0.0002). The rate of distant metastasis in patients with APN metastasis was significantly higher than that in patients without APN metastasis (68.8% vs. 36.7%, p = 0.012). The univariate analysis revealed that the differentiation, lymph node ratio, and APN metastasis were significantly associated with 5-year OS, and the preoperative CEA and CA19-9 levels and APN metastasis were significantly associated with 5-year RFS. The multivariate analysis showed that APN metastasis was an independent risk factor for 5-year OS and RFS. APN metastasis may be independently associated with the prognosis of patients with high-risk Stage III colon cancer.

Prognosis of Patients With Colorectal Cancer and Apical Lymph Node Metastasis at the Inferior Mesenteric Artery: A Systematic Review and Meta-Analysis

Background

This review was designed to compile the evidence on the prognosis of patients with colorectal cancer and apical lymph node (APN) metastasis and the long-term benefit of inferior mesenteric artery lymph node (IMA-LN) resection.

Methods

We searched the PubMed Central, Cochrane library, EMBASE, and MEDLINE databases from inception until May 2021 for relevant publications. We assess the quality of the studies using the Newcastle Ottawa scale. We conducted a random-effects model meta-analysis and report pooled hazard ratios (HRs) with 95% confidence intervals (CIs).

Results

We analyzed data from 13 studies conducted in Japan, China, and Korea with 6,193 participants. Most studies were retrospective in nature and of low quality. We found that patients with APN metastasis had shorter OSs (pooled HR, 2.41; 95% CI, 1.92–3.02) and PFSs (pooled HR, 2.42; 95% CI, 1.90–3.09) than the patients without the metastasis. We identified significant heterogeneity without publication bias for both outcomes. Moreover, our sensitivity analysis revealed robust estimates were robust for the individual effects.

Conclusion

Our findings suggest that patients with colorectal cancer and APN metastases have significantly worse OS and DFS than those without the metastasis. However, inclusion of low-quality retrospective studies with high heterogeneity limits the generalizability of study findings.

Preoperative carbon nanoparticle injection improves inferior mesenteric artery lymph node retrieval in patients with rectal cancer

BACKGROUND

Inferior mesenteric artery lymph node (station 253 node) metastasis occurs in approximately 0.3% to 13.9% of rectal cancer patients. This study examined whether carbon nanoparticles could aid in harvesting more station 253 nodes and evaluated the relationship between the number of station 253 nodes retrieved and station 253 node metastasis.

METHOD

A total of 480 consecutive rectal cancer patients were enrolled in this prospective cohort study between August 2014 and October 2018. Ninety-one patients (18.96%) received a preoperative submucosal injection of carbon nanoparticles (CN+ group), and 389 patients did not receive an injection (CN- group). The number of lymph node retrievals was analyzed, and the relevant risk factors for station 253 node metastasis were identified using univariate and multivariate analyses.

RESULTS

The mean number of station 251, 252, and 253 lymph nodes and total lymph nodes retrieved in the CN+ group were higher than that retrieved in the CN- group. The percentage of patients with ≥4 station 253 nodes retrieved (54.0% vs 28.3%, P = .004) were higher in the CN+ group than in the CN- group. Retrieval of ≥4 station 253 nodes was an independent risk factor for station 253 node metastasis (OR: 2.40, 95% CI: 1.22-4.74, P = .012).

CONCLUSION

The preoperative submucosal injection of carbon nanoparticles was helpful for increasing the number of station 253 nodes harvested, and a minimum of 4 examined station 253 nodes was necessary for standard D3 lymph node dissection in rectal cancer.

Prognostic Utility of Apical Lymph Node Metastasis in Patients With Left-sided Colorectal Cancer

BACKGROUND

Unlike the tumor nodes metastasis (TNM) lymph node classification, based solely on counts of nodal metastases, the Japanese system of classifying colorectal carcinoma (CRC) focuses on regional lymph node spread. In this study, we explored the prognostic utility of inferior mesenteric artery (IMA) apical lymph node (APN) metastasis.

PATIENTS AND METHODS

This was a retrospective study of patients with stage III left-sided CRC. All enrollees were subjected to D3 resection between April 2007 and December 2016 at the International Medical Center of Saitama Medical University and then stratified by histologic presence (APN+ group) or absence (APN- group) of tumor in APNs examined postoperatively. Ultimately, propensity score matching was invoked (1:2) and COX regression analysis was conducted, determining group rates of relapse-free survival (RFS) and cancer-specific survival (CSS).

RESULTS

A total of 498 patients were studied, grouped as APN+ (19/498, 3.8%) or APN- (479/498, 96.2%). Prior to matching, the APN+ (vs. APN-) group showed significantly more lymphatic involvement (73.7% vs. 47.8%; p=0.023), deep (T3/T4) tumor infiltration (100% vs. 78.9%; p=0.024), and nodal metastasis (N2: 84.2% vs. 27.6%; p<0.001). In addition, para-aortic nodal recurrences were significantly increased (15.7% vs. 2.0%; p<0.001), conferring worse RFS (p<0.001) and CSS (p=0.014) rates. Once baseline factors were matched, the two groups appeared similar in RFS (p=0.415) and CSS (p=0.649). Multivariate regression analysis indicated that elevated carcinoembryonic antigen (CEA) level and deep tumor infiltration were independent risk factors for RFS, whereas postoperative complications and tumor-positive node counts were independent risk factors for CSS. APN+ status was not a significant risk factor for RFS or CSS.

CONCLUSION

APN positivity may thus constitute a regional rather than systemic manifestation. The TNM staging based on the number of metastatic lymph nodes seems to be more reasonable than the regional lymph node classification method.

Apical Node Involvement Does Not Influence Prognosis After Potentially Curative Resection for Stage III Colorectal Cancer: A Competing Risks Analysis

OBJECTIVE

To examine the independent prognostic value of ALN status in patients with stage III CRC.

SUMMARY OF BACKGROUND DATA

Early CRC staging classified nodal involvement by level of involved nodes in the operative specimen, including both locoregional and apical node status, in contrast to the American Joint Committee on Cancer/tumor nodes metastasis (TNM) system where tumors are classified by the number of nodes involved. Whether ALN status has independent prognostic value remains controversial.

METHODS

Consecutive patients who underwent curative resection for Stage III CRC from 1995 to 2012 at Concord Hospital, Sydney, Australia were studied. ALN status was classified as: (i) ALN absent, (ii) ALN present but not histologically involved, (iii) ALN present and involved. Outcomes were the competing risks incidence of CRC recurrence and CRC-specific death. Associations between these outcomes and ALN status were compared with TNM N status results.

RESULTS

In 706 patients, 69 (9.8%) had an involved ALN, 398 (56.4%) had an uninvolved ALN and 239 (33.9%) had no ALN identified. ALN status was not associated with tumor recurrence [adjusted hazard ratio (HR) 1.02, 95% confidence interval (CI) 0.84-1.26] or CRC-specific death (HR 1.14, CI 0.91-1.43). However, associations persisted between TNM N-status and both recurrence (HR 1.58, CI 1.21-2.06) and CRC-specific death (HR 1.59, CI 1.19-2.12).

CONCLUSIONS

No further prognostic information was conferred by ALN status in patients with stage III CRC beyond that provided by TNM N status. ALN status is not considered to be a useful additional component in routine TNM staging of CRC.

Prognostic Significance of D3 Lymph Node for Survival in Patients With Colorectal Cancer

BACKGROUND

The aim of this study was to investigate the prognostic value of D3 lymph node (TSLN) for the survival of patients with colorectal cancer.

METHODS

A total of 156 patients with R0 resected colorectal cancer were selected from 2011 to 2015 to carry out a retrospective study. The survival rate according to the groups of positive lymph node number (N: 1-3, N2: 4-6, N3: ≥7) and TSLN (TSLN [-], TSLN [+]) was analyzed. The influences of covariates on the 5-year overall survival (OS) and 5-year disease-free survival (DFS) were determined by the Cox proportional risk model of backward stepwise analysis. Kaplan-Meier survival analysis was used to draw survival curves between and within groups.

RESULTS

During the median follow-up period (44.0 months), the 5-year DFS rate and OS rate were 45.0% and 46.0%, respectively. Survival analysis of the TSLN group showed that the 5-year OS rate and 5-year DFS rate in the TSLN (+) group (20.0 and 16.2%, respectively) were significantly lower than those in the TSLN (-) group (68.3 and 51.6%, respectively) (P < 0.001). The 5-year OS rate and DFS rate of the TSLN (+) and TSLN (-) subgroups in the N1 group were 16.7%, 33.3%, 56.7%, and 55.7%, respectively (P < 0.001). Multivariate analysis showed that positive lymph node, TSLN, and Pathological T stage were independent prognostic factors of DFS and OS for 5 years. Patients in the TSLN (+) group had a poorer prognosis.

CONCLUSIONS

TSLN metastasis is an independent factor influencing the prognosis of patients, and patients with TSLN (+) have a poor prognosis. As an independent prognostic factor, this factor should be considered when evaluating the prognosis of patients.

Fat-suppressed gadolinium-enhanced isotropic high-resolution 3D-GRE-T1WI for predicting small node metastases in patients with rectal cancer

Background

To investigate the application value of fat-suppressed gadolinium-enhanced isotropic high-resolution 3D-GRE-T1WI in regional nodes with different short-axis diameter ranges in rectal cancer, especially in nodes ≤5 mm.

Methods

Patients with rectal adenocarcinoma confirmed by postoperative histopathology were included, and all the patients underwent preoperative 3.0 T rectal magnetic resonance imaging (MRI) and total mesorectal excision (TME) within 2 weeks after an MR scan. The harvested nodes from specimens were matched with nodes in the field of view (FOV) of images for a node-by-node evaluation. The maximum short-axis diameters of all the visible nodes in the FOV of images were measured by a radiologist; the morphological and enhancement characteristics of these nodes were also independently evaluated by two radiologists. The χ² test was used to evaluate differences in morphological and enhancement characteristics between benign and malignant nodes. The enhancement characteristics were further compared between benign and malignant nodes with different short-axis diameter ranges using the χ² test. Kappa statistics were used to describe interobserver agreement.

Results

A total of 441 nodes from 70 enrolled patients were included in the evaluation, of which 111 nodes were metastatic. Approximately 85.5 and 95.6% of benign nodes were found to have obvious enhancement and homogeneous or mild-heterogeneous enhancement, respectively, whereas approximately 89.2 and 85.1% of malignant nodes showed moderate or mild enhancement and obvious-heterogeneous or rim-like enhancement, respectively. The area under the receiver operating characteristic (ROC) curve (AUC) values of the enhancement degree for identifying the overall nodal status, nodes ≤5 mm and nodes > 5 mm and ≤ 10 mm were 0.887, 0.859 and 0.766 for radiologist 1 and 0.892, 0.823 and 0.774 for radiologist 2, respectively. The AUCs of enhancement homogeneity were 0.940, 0.928 and 0.864 for radiologist 1 and 0.944, 0.938 and 0.842 for radiologist 2, respectively. Nodal border and signal homogeneity were also of certain value in distinguishing metastatic nodes.

Conclusions

Enhancement characteristics based on fat-suppressed gadolinium-enhanced isotropic high-resolution 3D-GRE-T1WI were helpful for diagnosing metastatic nodes in rectal cancer and were a reliable indicator for nodes ≤5 mm.

Inferior Mesenteric Artery Lymph Node Metastasis Is an Independent Prognostic Factor for Stage III Sigmoid Colon and Rectal Cancer

It is unclear whether the number or distribution of lymph node metastases can provide a more accurate prognosis. The aim of this study was to evaluate the prognostic impact of inferior mesenteric artery (IMA) lymph node metastasis (LNM) in sigmoid colon and rectal cancer. We included 188 patients who underwent curative resection for stage III sigmoid colon and rectal cancer between January 2001 and December 2012. Patients were divided into 2 groups based on the presence of IMA-LNM (LNM-positive versus LNM-negative group). Clinicopathologic characteristics, 3-year recurrence-free survival and 5-year overall survival rates, and recurrence patterns were compared between the 2 groups. Of 188 patients, 9 patients (4.79%) were in the LNM-positive group. After curative resection, 3-year recurrence-free survival and 5-year overall survival rates were significantly lower in the LNM-positive group compared to the LNM-negative group (44.44% versus 69.98%, P = 0.016 for 3-year recurrence-free survival and 48.61% versus 81.73%, P = 0.018 for 5-year overall survival). Multivariate analysis revealed that the presence of IMA-LNM (P = 0.04), not the number of LNMs (P = 0.153), was an independent prognostic factor for recurrence-free survival. The para-aortic LNM rate was significantly higher in the LNM-positive group (P = 0.0078). IMA-LNM is an independent predictor of survival for stage III sigmoid colon and rectal cancer patients. Evaluation of IMA-LNM enables accurate estimation of patient prognosis and enhances appropriate postoperative therapy.

Clinical practice guidelines for the surgical treatment of rectal cancer: a consensus statement of the Hellenic Society of Medical Oncologists (HeSMO)

In rectal cancer management, accurate staging by magnetic resonance imaging, neo-adjuvant treatment with the use of radiotherapy, and total mesorectal excision have resulted in remarkable improvement in the oncological outcomes. However, there is substantial discrepancy in the therapeutic approach and failure to adhere to international guidelines among different Greek-Cypriot hospitals. The present guidelines aim to aid the multidisciplinary management of rectal cancer, considering both the local special characteristics of our healthcare system and the international relevant agreements (ESMO, EURECCA). Following background discussion and online communication sessions for feedback among the members of an executive team, a consensus rectal cancer management was obtained. Statements were subjected to the Delphi methodology voting system on two rounds to achieve further consensus by invited multidisciplinary international experts on colorectal cancer. Statements were considered of high, moderate or low consensus if they were voted by ≥80%, 60-80%, or <60%, respectively; those obtaining a low consensus level after both voting rounds were rejected. One hundred and two statements were developed and voted by 100 experts. The mean rate of abstention per statement was 12.5% (range: 2-45%). In the end of the process, all statements achieved a high consensus. Guidelines and algorithms of diagnosis and treatment were proposed. The importance of centralization, care by a multidisciplinary team, adherence to guidelines, and personalization is emphasized.

Significance and prognostic value of increased serum direct bilirubin level for lymph node metastasis in Chinese rectal cancer patients

AIM: To determine the significance of increased serum direct bilirubin level for lymph node metastasis (LNM) in Chinese rectal cancer patients, after those with known hepatobiliary and pancreatic diseases were excluded.

METHODS: A cohort of 469 patients, who were treated at the China-Japan Friendship Hospital, Ministry of Health (Beijing, China), in the period from January 2003 to June 2011, and with a pathological diagnosis of rectal adenocarcinoma, were recruited. They included 231 patients with LNM (49.3%) and 238 patients without LNM. Follow-up for these patients was taken through to December 31, 2012.

RESULTS: The baseline serum direct bilirubin concentration was (median/inter-quartile range) 2.30/1.60-3.42 μmol/L. Univariate analysis showed that compared with patients without LNM, the patients with LNM had an increased level of direct bilirubin (2.50/1.70-3.42 vs 2.10/1.40-3.42, P = 0.025). Multivariate analysis showed that direct bilirubin was independently associated with LNM (OR = 1.602; 95%CI: 1.098-2.338, P = 0.015). Moreover, we found that: (1) serum direct bilirubin differs between male and female patients; a higher concentration was associated with poor tumor classification; (2) as the baseline serum direct bilirubin concentration increased, the percentage of patients with LNM increased; and (3) serum direct bilirubin was associated with the prognosis of rectal cancer patients and higher values indicated poor prognosis.

CONCLUSION: Higher serum direct bilirubin concentration was associated with the increased risk of LNM and poor prognosis in our rectal cancers.

Pre-operative predictive factors for intra-operative pathological lymph node metastasis in rectal cancers

BACKGROUND

A number of clinicopathologic factors have been found to be associated with pathological lymph node metastasis (pLNM) in rectal cancer; however, most of them can only be identified by expensive high resolution imaging or obtained after surgical treatment. Just like the Child-Turcotte-Pugh (CTP) and the model for end-stage liver disease (MELD) scores which have been widely used in clinical practice, our study was designed to assess the pre-operative factors which could be obtained easily to predict intra-operative pLNM in rectal cancer.

METHODS

A cohort of 469 patients who were treated at our hospital in the period from January 2003 to June 2011, and with a pathologically hospital discharge diagnosis of rectal cancer, were included. Clinical, laboratory and pathologic parameters were analyzed. A multivariate unconditional logistic regression model, areas under the curve (AUC), the Kaplan-Meier method (log-rank test) and the Cox regression model were used.

RESULTS

Of the 469 patients, 231 were diagnosed with pLNM (49.3%). Four variables were associated with pLNM by multivariate logistic analysis, age<60 yr (OR=1.819; 95% CI, 1.231-2.687; P=0.003), presence of abdominal pain or discomfort (OR=1.637; 95% CI, 1.052-2.547; P=0.029), absence of allergic history (OR=1.879; 95% CI, 1.041-3.392; P=0.036), and direct bilirubin ≥ 2.60 μmol/L (OR=1.540; 95% CI, 1.054-2.250; P=0.026). The combination of all 4 variables had the highest sensitivity (98.7%) for diagnostic performance. In addition, age<60 yr and direct bilirubin ≥ 2.60 μmol/L were found to be associated with prognosis.

CONCLUSION

Age, abdominal pain or discomfort, allergic history and direct bilirubin were associated with pLNM, which may be helpful for preoperative selection.

Drug allergy and the risk of lymph node metastasis in rectal cancer

Background

Previous epidemiologic studies have reported that a history of allergy is associated with reduced risk of colorectal cancer and other malignancies. However, no information is available for the association between allergy and the risk of lymph node metastasis. Our study was designed to determine this association in rectal cancer.

Methods

Patients who were treated at our hospital in the period from January 2003 to June 2011, and with a pathologically hospital discharge diagnosis of rectal adencarcinoma, were included. The clinical, laboratory, and pathologic parameters were analyzed. A multivariate logistic regression model was used to determine the association. Moreover, for type of allergic drug, sub-group analysis was performed.

Results

469 patients were included, including 231 with pathological lymph node metastasis (pLNM) (49.3%) and 238 without pLNM. Univariate analysis showed, compared with patients without pLNM, patients with pLNM had a younger age (60.6±12.8 yr vs. 63.6±12.2 yr, P = 0.012), a lower percentage of drug allergy (8.7% vs. 16.0%, P = 0.016), an increased CEA (median/interquartile-range 5.40/2.40–13.95 vs. 3.50/2.08–8.67, P = 0.009), and a lower serum sodium (141±3.1 mmol/L vs. 142±2.9 mmol/L, P = 0.028). Multivariate analysis showed that drug allergy was associated with a reduced risk of pLNM (OR = 0.553; 95% CI, 0.308–0.994; P = 0.048). In addition, our results showed that: (1) for tumor classification, patients with drug allergy had a higher percentage of group patients with pT1/pT2; and (2) for type of allergic drug, this inverse association was found for penicillins, not for other allergic drugs.

Conclusion

Drug allergy is associated with a reduced risk of pLNM in rectal cancer.

A scoring system to predict inferior mesenteric artery lymph node metastasis and prognostic value of its involvement in rectal cancer

PURPOSE

The aim of this study is to establish a prediction scoring system for inferior mesenteric artery (IMA) lymph node metastasis and to assess the prognostic impact of dissection of positive IMA node on patients with stage III rectal cancer.

METHODS

A retrospective study was performed in 264 patients with stage III rectal cancer undergoing curative surgery. Clinicopathological, survival, and recurrence data were compared between 29 patients with positive IMA nodes and 235 patients with negative IMA nodes. Clinicopathological data which were found to be significantly associated with IMA nodal status were incorporated into a scoring system.

RESULTS

In the training samples, tumor differentiation and preoperative serum CEA were significant predictors of IMA node metastasis in multivariate analysis, which were incorporated into a scoring system. Using receiver operating characteristic curve analysis, we determined a cutoff value of 46.5 for scores, at which the system's sensitivity was 86 % and specificity 61 %. When applied to testing sample, the sensitivity was 80 % and specificity 60 %. Survival analysis showed that 5-year disease-free survival rate (5-DFS) and 5-year overall survival (5-OS) in the positive IMA node group (24.4 and 27.6 %, respectively) were significantly lower than in the negative IMA node group (61.8 and 71.3 %, respectively) (P < 0.001). Furthermore, multivariate analysis indicated that IMA lymph node metastasis was an unfavorable independent prognostic factor for 5-DFS and 5-OS.

CONCLUSIONS

IMA lymph node metastasis is an independent poor prognostic factor for stage III rectal cancer. The prediction scoring system for IMA node metastasis would be beneficial in determining the appropriate level of IMA ligation.