Impact of neoadjuvant therapy on nodal harvest in clinical stage III rectal cancer: Establishing optimum cut-offs by disease response.

INTRODUCTION: A minimum lymph node harvest (LNH) of 12 is the current standard for appropriate nodal staging in resectable rectal cancer. However, the rise of neoadjuvant chemoradiation (NCRT) and total neoadjuvant therapy (TNT) has been associated with decreasing number of LNH. We hypothesize that as tumor response to neoadjuvant therapy increases, the optimum for LNH to achieve appropriate nodal staging should decrease. METHODS: Patients with clinical stage III rectal adenocarcinoma who underwent NCRT/TNT followed by resection were identified from the National Cancer Database. A JoinPoint regression analysis was used to determine the LNH for each tumor regression grade (TRG) category beyond which the rate of positive nodes does not significantly change. RESULTS: Thirteen thousand four hundred and twenty-six patients met inclusion criteria. Of these, 2406 (17.9%) achieved TRG 0 or ypT0 and 8210 (61.2%) achieved ypN0. Collectively, 2043 patients (15.2%) were reported to have a pathologic complete response (ypT0 ypN0). Positive pathologic nodes were found in 15%, 23%, 31%, 54%, and 53% as ypT stage increased from ypT0 to ypT4, respectively. Similarly, ypN+ rates were 15%, 36%, 41%, and 55% in TRG 0-3. No JoinPoint was identified for TRG 0, whereas inflection points were found at 6-10 nodes for TRG1 (p = 0.002) and TRG 2 (p = 0.016), and at 11-15 nodes for TRG 3. CONCLUSION: The benchmark of retrieving 12 nodes in resectable stage III rectal cancer is not consistently achieved after NCRT/TNT. We demonstrate that the LNH requirement to establish accurate pathologic nodal staging can vary depending on the tumor response to neoadjuvant therapies.

The impact of methylene blue in colon cancer: a retrospective multicentric study.

INTRODUCTION: Discussions about the optimal lymph node (LN) count and its therapeutic consequences have persisted over time. The final LN count in colorectal tissues is affected by a variety of variables (patient, tumor, operation, pathologist, immune response). Methylene blue (MB) intra-arterial injection is a simple and inexpensive procedure that can be used to enhance lymph node count. AIM: Analyze whether there is a statistically significant difference between intra-arterial methylene blue injection and conventional dissection for the quantification of lymph nodes and determine if there is a variation in the quality of lymph node acquisition. METHODS AND RESULTS: Between 2015 and 2022, we conducted a retrospective analysis of colon cancer specimens. Data on the tumor's features, the number of lymph nodes, the number of lymph nodes that were positive, and other factors had been collected. The number of identified lymph nodes was highly significantly improved in the study group (P < 0.05). There is not a significant statistical difference between groups regarding the metastatic lymph node harvest. The group with injection of intra-arterial methylene blue shows a significantly decreased (P < 0.05) of the of cases with less than 12 lymph nodes recovered comparing with the control group. CONCLUSION: Colon cancer specimens can be easily evaluated concerning lymph nodes using the methylene blue method. Therefore, we strongly advise this approach as a standard procedure in the histological evaluation of colon cancer specimens in order to maximize the identification of lymph nodes. However, the detection of metastatic lymph nodes was unaffected significantly.

Neoadjuvant Chemoradiation for Rectal Cancer Achieves Satisfactory Tumour Regression and Local Recurrence - Result of a Dedicated Multi-disciplinary Approach from a South Asian Centre.

BACKGROUND: Pre-operative long-course chemoradiotherapy (CRT) for rectal cancer has resulted in improvement in rates of restorative rectal resection and local recurrence by inducing tumour downstaging and downsizing. Total mesorectal excision (TME) is a standardised surgical technique of low anterior resection aimed at the prevention of local tumour recurrence. The purpose of this study was to evaluate tumour response following CRT in a standardised group of patients with rectal cancer. METHODS: One hundred and thirty-one patients (79 male; 52 female, median age 57; interquartile range 47-62 years) of 153 with rectal cancer who underwent pre-operative long-course CRT were treated by standardised open low anterior resection at a median of 10 weeks post-CRT. Sixteen of 131 (12%) were 70 years or older. Median follow-up at the time of analysis was 15 months (interquartile range 6-45 months). Pathology reports were analysed based on AJCC-UICC classification using the TNM system. Data recorded were overall/subgrades of tumour regression; good, moderate or poor, lymph node harvest, local recurrence, disease-free and overall survival using standard statistical methods. RESULTS: 78% showed tumour regression post-CRT; 43% displayed good tumour regression/response while 22% had poor tumour regression/response. All patients had a pre-operative T-stage of either T3 or T4. Post-operation, good responders had a median T stage of T2 vs. T3 in poor responders (P = 0.0002). Overall, the median lymph node harvest was < 12. There was no difference in the number of nodes harvested in good vs. poor responders (Good/moderate-6 nodes vs. Poor- 8; P = 0.31). Good responders tended to have a lesser number of malignant nodes vs. poor responders (P = 0.31). Overall, local recurrence was 6.8% and the anal sphincter preservation rate was 89%. Predicted 5-year disease-free and overall survival were similar between good and poor responders. CONCLUSION: Long-course CRT resulted in satisfactory tumour regression and enabled consideration for safe, sphincter-saving resection in rectal cancer. A dedicated multi-disciplinary team approach achieved a global benchmark for local recurrence in a resource-limited setting.

Lymph node stain after radical resection of rectal cancer mainly increased the harvest of mini lymph node: A randomized controlled trial.

AIM: The lymph node status plays an important role in rectal cancer, which depends on adequate lymph node harvest. Lymph node stain techniques increase the lymph node harvest. The aim of this prospective study is to investigate which subgroups of lymph nodes harvested were increased mostly. METHODS: From May 2020 to May 2022, 172 stage II-III rectal cancer patients were randomized to methylene blue (MB) stained group or unstained group to retrieve the lymph nodes. Methylene blue solution was injected into the inferior mesenteric artery, we dissected lymph nodes by palpation and sight. The lymph nodes were divided into 3 groups depending on the anatomy (main lymph nodes, superior rectal and perirectal lymph nodes (SPLNs), and pericolic lymph nodes located beyond 10 cm proximal to the tumor), and 3 groups depending on the short diameter of the nodes (big: ≥ 5 mm, small: 5-2 mm, mini: ≤ 2 mm). RESULTS: The number of lymph nodes harvested with MB was significantly higher (22.0 (14.8, 32.0) vs 14.5 (11.0, 22.0); p < 0.001) without difference in positive patients or number of positive nodes. The positive rate of the big node was 3.5%, the small node was 1.9%, and the mini node was 0.2%. In the subgroup analysis, the median number of mini lymph nodes in the MB-stained group was significantly more than that of the unstained group (median (IQR): 9.0 (6.0, 14.0) vs 4.0 (2.0,6.0), p < 0.001); and the median number of SPLNs in the MB-stained group were significantly more than that of the unstained group (median (IQR): 15.0 (9.0, 19.0) vs 10.0 (6.0, 13.3), p < 0.001); these differences were existing in both patients with and without neoadjuvant treatments. CONCLUSION: Intra-arterial injection of MB can significantly increase the number of lymph nodes harvested in rectal cancers, especially those mini lymph nodes. However, methylene blue staining did not significantly increase the number of positive lymph nodes and the proportion of patients with more than 12 lymph nodes, or affect lymph node staging accuracy after radical resection of rectal cancer.

The topographical distribution of lymph node metastases in colon cancer resections.

In accordance with international guidelines all lymph nodes in colon cancer specimens must be examined to obtain accurate staging. This study aimed to determine the topographical location of lymph node metastases and evaluate if a more limited sampling approach could be an alternative. Partial colectomies received at the Department of Pathology, Zealand University Hospital during a six-month period were included. At the macroscopic examination, each specimen was divided into three different segments: a segment containing the index tumor and the tumor-feeding artery, an oral and an anal segment. The number of lymph nodes and lymph node metastases were registered separately for each segment. Resections from 93 patients were included. Of 2466 lymph nodes, 1839 (74.6 %) were located in the tumor segment, 308 (12.5 %) in the oral, and 319 (12.9 %) in the anal segment, respectively. In 133 (5,4 %) lymph nodes a metastasis was present. Of these 129 (97.0 %) were located in the tumor segment, one (0.8 %) in the oral segment, and three (2.3 %) in the anal segment. No patients had metastasis in the oral or anal segments without metastases also being present in the tumor segment leading to consideration of the need for lymph node harvest of the complete specimen upon initial examination. As such, the segment containing the index tumor and tumor-feeding artery could be regarded as a sentinel segment indicating a potential need for lymph node dissection in the oral and anal segments.

Segmental resection of splenic flexure colon cancers provides an adequate lymph node harvest and is a safe operative approach - an analysis of the ACS-NSQIP database.

INTRODUCTION: Fewer than 10% of colon cancers are found at the splenic flexure. A standard surgical approach to these cancers has not been defined. The goal of this study was to compare lymph node harvest and post-operative morbidity between segmental resection and formal left hemicolectomy for splenic flexure colon cancers. METHOD: Patients diagnosed with a splenic flexure cancer were identified from the 2012-2018 ACS-NSQIP colectomy-targeted database. Patients were categorized based on type of surgical resection - left hemicolectomy with colorectal anastomosis or segmental colectomy with colocolonic anastomosis. Demographic, clinicopathologic, and post-operative outcomes were compared between groups. Factors independently associated with lymph node harvest, operative time, and post-operative morbidity were investigated by linear and binomial logistic regression models. RESULTS: A total of 3,049 patients underwent colectomy for a splenic flexure cancer. Of these, 83.6% had a segmental colectomy and 73% were performed by a minimally invasive approach. T- and N-stage did not differ between segmental and left hemicolectomy groups (p = 0.703 and p = 0.429, respectively). Inadequate nodal harvest (< 12 nodes) was infrequent and similar between the two procedures (7.4% vs. 9.1%, p = 0.13). Operative time was significantly shorter for segmental colectomy (213 ± 83.5 min vs. 193 ± 84.1 min, p < 0.0001) and major morbidity was similar between the two surgical techniques (8.4% vs. 8.9%, p = 0.75). After accounting for demographic, clinicopathologic, and operative factors, binomial logistic regression showed that type of procedure was not significantly associated with LN harvest (OR 0.80, 95%CI 0.54-1.17) or major morbidity (OR 1.17, 95%CI 0.36-3.81). However, on linear regression, segmental splenic flexure resection was associated with shorter operative time (estimate 20.29, 95%CI 12.61-27.97, p < 0.0001). CONCLUSION: Splenic flexure resection for colon cancer is associated with an adequate lymph node harvest. Compared to a formal left hemicolectomy, a segmental resection also has a shorter operative time with equivalent post-operative morbidity.

Quality of oncological resection criteria in minimally invasive esophagectomy.

BACKGROUND: Even though minimally invasive esophageal surgery (MIE) is spreading, questions remain regarding its oncological outcomes. The aim of this study was to assess the quality of oncological resection criteria in MIE. METHODS: All patients undergoing a two-way Ivor Lewis esophagectomy for esophageal or junctional cancer between 2010 and 2020 in a single tertiary upper gastrointestinal surgery ward were analyzed retrospectively. The following oncological criteria were analyzed: lymph node (LN) harvest and location, positive lymph node rate, margins, and R0 rates. They were compared between the MIE group (thoracoscopy + laparoscopy) and the hybrid group (H/O, thoracotomy + laparoscopy). RESULTS: Among the 240 patients included, 34 (14%) had MIE and 206 a hybrid esophagectomy. Main surgical indication was lower thoracic adenocarcinoma and the rate of neoadjuvant treatments administered (chemotherapy or chemoradiotherapy) was comparable between both groups (p = 1.0). LN harvest was significantly higher in the MIE group (31 ± 9 vs. 28 ± 9, p = 0.04) as well as thoracic LN harvest (14 ± 7 vs. 11 ± 5, p = 0.002). When analyzing patients according to T stage and response to neoadjuvant treatments, patients with T1 and T2 tumors and patients with a poor pathological response (TRG3, 4, 5) had a significantly higher LN harvest when undergoing a minimally invasive approach (p = 0.021 and p = 0.01, respectively). Positive LN rates (1.26 ± 3.63 in the MIE group vs. 1.60 ± 2.84 in the H/O group, p = 0.061), R0 rates (97% vs. 98.5%, p = 0.46) as well as proximal (p = 0.083), distal (p = 0.063), and lateral (p = 0.15) margins were comparable between both approaches. CONCLUSION: MIE seems oncologically safe and may even be better than the open approach in terms of LN harvest especially in patients with T1 and T2 tumors and in poor responders.

Higher lymph node harvest in patients with a pathologic complete response after neoadjuvant therapy for esophageal cancer is associated with improved survival.

BACKGROUND AND OBJECTIVES: Lymph node harvest during esophagectomy has been associated with improved survival for esophageal cancer but the value of enhanced lymph node harvest following complete pathologic response (pCR) is debated. This study investigated if increasing lymph node harvest in esophageal cancer patients with a pCR after neoadjuvant therapy and esophagectomy is associated with improved survival. METHODS: We queried the National Cancer Data Base for patients with esophageal cancer between 2004 and 2014 who underwent neoadjuvant chemotherapy or chemoradiation therapy followed by esophagectomy found to have pCR. Multivariable Cox modeling was utilized to evaluate the impact of increasing lymph node counts on overall survival (OS). RESULTS: A total of 1373 patients met inclusion criteria. A National Comprehensive Cancer Network compliant lymphadenectomy of ≥15 nodes was associated with improved survival (66.7% vs 51.1%; P < .001). Cox modeling showed that the first node cutoff to demonstrate a statistically significant improvement in OS was ≥7 nodes (hazard ratio [HR], 95% confidence interval [CI]: 0.81, 0.68-0.97; 5-year OS: 54.2%) with a trend of decreasing and statistically significant HRs until ≥25 nodes (HR, 95% CI: 0.52, 0.37-0.72; 5-year OS: 68.4%). CONCLUSIONS: High negative node counts after neoadjuvant therapy and esophagectomy are associated with improved survival in patients with pCR.

Predictors of lymph node metastases in patients with mucinous appendiceal adenocarcinoma.

BACKGROUND: Lymph node metastasis (LN+) is a prognostic factor in appendiceal cancers, but predictors and outcomes for LN+ in mucinous appendiceal adenocarcinoma (MAC) remain poorly defined. METHODS: Patients were identified from the 2010 to 2016 NCDB who underwent surgical resection as first-line management for Stage I-III mucinous appendiceal cancer. A LN+ risk-score model was developed using multivariable regression on a training data set and internally validated using a testing data set. Three-year overall survival (OS) was analyzed by Cox proportional hazards regression. RESULTS: Of 1158 patients, LN+ (N = 244, 21.1%) patients were more likely to have higher pT group and grade of disease, lymphovascular invasion (LVI), and positive margins on univariate analyses. Predictive factors associated with LN+ on multivariable analysis included positive surgical margins (odds ratio [OR] 3.00, P <.0001), higher grade (moderately differentiated: OR, 2.16, P < .0001; poorly or undifferentiated: OR, 3.07, P < .0001), and LVI (OR, 7.28, P < .0001). A validated risk-score model using these factors was developed with good performance (AUC 0.749). LN+ patients had a worse 3-year OS compared with LN- patients (17.4% vs 82.6%, hazard ratio 1.96, P = .001). CONCLUSIONS: LN+ is associated with worse survival in patients with MAC. A risk-score model using margin status, LVI, and grade can accurately risk stratify patients for LN+.

Effect of total number of harvested lymph nodes on survival outcomes after curative resection for gastric adenocarcinoma: findings from an eastern high-volume gastric cancer center.

BACKGROUND: Greater lymph node retrieval in gastric cancer improves staging accuracy and may improve survival from increased clearance of nodal micrometastasis. This retrospective cohort study investigated if more lymph nodes removed in gastric cancer increases survival and if such effect is stage-specific due to differential risks of nodal micrometastasis and systemic disease. METHODS: The prospectively collected database of curatively resected gastric cancer patients in National Cancer Center, South Korea between 2000 and 2009 was reviewed. Disease-free survival (DFS) and overall survival (OS) for all patients and for each stage according to number of lymph nodes examined (1-30, 31-45, > 45) were analyzed. RESULTS: Of 4049 patients, 96.6% and 98.4% underwent D2 (perigastric and extragastric) lymphadenectomy and had ≥ 15 lymph nodes examined. Mean number of nodes examined was 43. Five-year OS & DFS rates were 83.3% and 80.7%. Patients with > 45 nodes examined had significantly lower DFS (p = 0.002) and OS (p = 0.007) compared to those with 1-30 and 31-45 nodes. However, proportion of patients with > 45 nodes examined increased with stage (p = 0.0005). Per stage, there was no significant difference in DFS and OS according to number of nodes examined except for stage IIIA favoring more nodes (p = 0.018 and p = 0.044, respectively). Similar trend was seen in stage IIB. Number of examined nodes positively correlated with number of pathologic nodes for all patients (r = 0.144, p < .001) but not for stage IIB and IIIA. Number of nodes examined was a significant survival predictor in stage IIIA. CONCLUSION: Greater lymph node harvest showed improved survival in intermediate-stage gastric cancer.

The positive impact of surgical quality control on adequate lymph node harvest by standardized laparoscopic surgery and national quality assessment program in colorectal cancer.

PURPOSE: We aimed to present the factors associated with lymph node harvest (LNH) and seek whether surgical quality control measures can improve LNH. METHODS: From a prospectively collected data at a single institution, 874 CRC patients who underwent curative surgery between 2004 and 2013 were included. Factor and survival analyses were performed regarding LNH. Subgroup analysis was performed according to LNH group (LNH ≥ 12 vs LNH < 12) and year of surgery (2004-2008, 2009-2011, and 2012-2013 group). RESULTS: In the multivariate analysis, tumor location (OR 0.6, p < 0.001), stage (OR 1.95, p < 0.001), and year of surgery (OR 3.86, p < 0.001) showed an association with adequate LNH. In the subgroup analysis categorized by the year of surgery, surgical quality control measures by standardized laparoscopic surgery (OR 52.91, p < 0.001) showed notable association with adequate LNH. Comparing the 2009-2011 and 2012-2013 group, the national quality assessment program additionally improved adequate LNH percentage (83.9 vs 94.3%). In the survival analysis, disease-free survival (DFS) differed according to year of surgery, standardized laparoscopic surgery with high vascular ligation, and adequate LNH by stage. In the overall survival (OS) analysis, the LNH-related factors did not show significant difference. CONCLUSIONS: Through standardized laparoscopic surgery with high vascular ligation and national quality assessment program, surgical quality control had a positive impact on the increase of adequate LNH. Improving the modifiable LNH factors resulted in the enhancement of adequate LNH and related DFS.

A modified sentinel lymph node technique combined with endoluminal loco-regional resection for the treatment of rectal tumours: a 14-year experience.

AIM: After endoluminal loco-regional resection (ELRR) by transanal endoscopic microsurgey (TEM) the N parameter may remain undefined. Nucleotide-guided mesorectal excision (NGME) improves the lymph node harvest. The aim of the present study is to evaluate the long-term oncological results after ELRR with NGME. METHOD: A total of 57 patients were enrolled over the period January 2001 to June 2015. All patients underwent ELRR by TEM. Prior to surgery, 99 m-technetium-marked nanocolloid was injected into the peritumoural submucosa. After removal of the specimen, the residual defect was probed to detect any residual radioactivity and 'hot' mesorectal fat was excised. All patients were included in a 5-year follow-up programme. RESULTS: Significant radioactivity in the residual cavity was found in 28 out of 57 patients (49%). The mean number of lymph nodes harvest in irradiated and nonirradiated patients was 1.66 and 2.76, respectively. After 68.2 months' follow-up overall survival was 91.2%, disease-related mortality 3.5% and disease-free survival 89.5%. Two patients developed pulmonary metastases: one ypT3N0 patient underwent lung lobectomy after chemotherapy and one pT2N0 patient was managed with lung radiotherapy. Both patients are currently alive and disease-free at 48 months' follow-up. Two patients developed local recurrence 1 year after ELRR, both treated with neoadjuvant chemo-radiotherapy and total mesorectal excision. Comparing the present series with previous patients who did not undergo NGME, an increased number of harvested lymph nodes were observed, with a statistically significant difference (P = 0.0085). CONCLUSION: NGME during ELRR improves the lymph node harvest and staging accuracy. The long-term results showed satisfactory local (3.5%) and distant (7%) recurrence rates.

Intra-arterial methylene blue injection into ex vivo colorectal cancer specimens improves lymph node staging accuracy: a randomized controlled trial.

AIM: A randomized controlled trial was carried out to study the effect of a recently proposed technique of ex vivo intra-arterial methylene blue injection of the surgical specimen removed for colorectal cancer on lymph node harvest and staging. METHOD: Between May 2012 and February 2013, 100 consecutive colorectal cancer resection specimens in a single institution were randomly assigned to intervention (methylene blue injection) and control (standard manual palpation technique) groups before formalin fixation. The specimen was then examined by the histopathologist for lymph nodes. RESULTS: Both groups were similar for age, sex, site of tumour, operation and tumour stage. In the intervention group, a higher number of nodes was found [median 23 (5-92) vs. 15 (5-37), P < 0.001], with only one specimen not achieving the recommended minimum standard of 12 nodes [1/50 (2%) vs. 8/50 (16%), P = 0.014]. However, there was no upstaging effect in the intervention group [23/50 (46.0%) vs. 20/50 (40.0%); P = 0.686]. With a significantly lower number of nodes harvested in rectal cancer, the positive effect of the intervention was particularly observed in the patients who underwent preoperative neoadjuvant radiotherapy [median 30 nodes (12-57) vs. 11 (7-15); P = 0.011; proportion of cases with < 12 nodes 0/5 vs. 5/8 (62.5%), P = 0.024]. CONCLUSION: Ex vivo intra-arterial methylene blue injection increases lymph node yield and can help to reduce the number of cases with a lower-than-recommended number of nodes, particularly in patients with rectal cancer having neoadjuvant treatment. The technique is easy to perform, cheap and saves time.

The impact of methylene blue in colorectal cancer: Systematic review and meta-analysis study.

PURPOSE: In patients with colorectal cancer (CRC), the most important factor to decide the need of adjuvant chemotherapy is the histological lymph node (LN) evaluation. Our work aimed to give a broad view over the use of methylene blue and its consequences in the number of lymph node harvest. METHODS: PUBMED, WEB OF SCIENCE and EMBASE databases were consulted, retrieving clinical trials, which mentioned the used of intra-arterial methylene blue in patients with colorectal cancer. RESULTS: Eighteen clinical trials analyzing the use of intra-arterial methylene blue in specimens of colorectal cancer were selected. The articles show a statistical difference between the use of methylene blue and the classical dissection in both variable at study. The results of the statistical analysis of the lymph node harvest variable demonstrate a significant statistical difference between the group that received methylene blue injection and the group that underwent conventional dissection. There is a significant statistical difference between the experimental and control groups for the ideal lymph node harvest (lymph node harvest count greater than 12). CONCLUSION: The use of intra-arterial methylene blue revealed a high potential for the quantification of lymph nodes, considering the increase of lymph node harvest and the higher percentage of cases with more than 12 lymph nodes count, albeit the high heterogeneity between the studies in terms of reported results. Future investigations with controlled double blinded studies obtaining better categorized results should be conducted in order to better evaluate this technique and compare it to the current paradigm.

Arm lymphedema after vascularized lymph node harvest following Covid-19 vaccination.

There is evidence that COVID-19 vaccines may affect the lymphatic system. We report a case of a 40-year-old female who had undergone lymph node transfer for treating primary lymphedema of the legs. Six months later, the patient developed lymphedema of the right arm closely related to mRNA vaccination against COVID-19.

Factors related to lymph node harvest: does a recovery of more than 12 improve the outcome of colorectal cancer?

AIM: The nodal harvest was studied to identify factors that affected the number of lymph nodes (LNs) retrieved in patients undergoing curative surgery for colorectal cancer. The influence of predictive factors on overall and disease-free 5-year survival was analysed. METHOD: All patients diagnosed with colorectal cancer who underwent oncological resection consecutively from January 1996 to December 2011 in a single institution have been studied. Factors influencing LN retrieval were analysed. A logistic regression analysis was performed to determine the factors that predicted a recovery of more than 12 LNs. A Cox regression analysis was made to identify the predictive factors of overall and disease-free 5-year survival. RESULTS: A total of 1166 patients were included in the study. The factors associated with the number of LNs harvested in surgical resections were age, colorectal surgeon, right colectomy, total colectomy, year of surgery, number of LN metastases and lymphocyte response. The factors that predicted a recovery of ≥ 12 LNs were age < 60 years, right colectomy, year of surgery and expert pathologist. A recovery of ≥ 12 LNs did not show significant differences in overall and disease-free 5-year survival, but the factor of colorectal surgeon did. CONCLUSION: Number of LN metastases, lymphocyte response, type of surgical resection, age of patient and colorectal surgeon can predict the LN harvest. Survival in colorectal cancer, however, is probably more influenced by the performance of the operation by an expert surgeon than by recovery of more than 12 LNs.

The importance of lymph node retrieval and lymph node ratio following preoperative chemoradiation of rectal cancer.

AIM: Preoperative chemoradiation (CRT) for rectal cancer decreases the number of examined lymph nodes (NELN) found in the resected specimen. However, the prognostic role of lymph node evaluation including overall numbers and the lymph node ratio (LNR) in patients having preoperative CRT have not yet been defined. The study has assessed the influence of CRT on the NELN and on lymph node number and LNR on the survival of patients with rectal cancer. METHOD: Between 2003 and 2011, 508 patients with nonmetastatic rectal cancer underwent mesorectal excision. Of these 123 (24.2%) received preoperative CRT. Univariate and multivariate analysis was performed to define the role of NELN and LNR as prognostic indicators of survival. RESULTS: Neoadjuvant CRT significantly reduced the NELN (P < 0.0001). Disease-free survival (DFS) and overall survival (OS) of patients with fewer or more than 12 nodes retrieved did not differ statistically. Node-negative patients with six or fewer lymph nodes were significantly associated with a poor DFS and OS on univariate analysis (P = 0.03 and P = 0.03). LNR significantly influenced the DFS and OS on multivariate analysis [DFS, P = 0.0473, hazard ratio (HR) 2.4980, 95% confidence interval (CI) 1.2631-9.4097; OS, P = 0.0419, HR 1.1820, 95% CI 1.1812-10,710]. CONCLUSION: The cut-off of 12 lymph nodes does not influence survival and should not be considered for cancer-specific prediction of patients having neoadjuvant CRT. In contrast LNR is an independent prognostic predictor of DFS and OS in such patients.

Survival outcomes for right-versus left-sided colon cancer and rectal cancer in England: A propensity-score matched population-based cohort study.

INTRODUCTION: The aim of this study was to evaluate 5-year overall survival (OS) in patients operated on for potentially curable right versus left-sided colon cancer and rectal cancer in England. MATERIALS AND METHODS: A retrospective propensity-score matched population-based cohort study was performed using data from English Hospital Episode Statistics, Office for National Statistics and National Bowel Cancer Audit dataset. Patients ≥18 who underwent elective resection for right-colon, left-colon, or rectal cancer between 2000 and 2015 were included. Patients were matched using propensity scores with the dependant variable being site of primary tumour (right-colon, left-colon, or rectum) and independent variables age, Charlson comorbidity index, operation year and Duke's stage. The primary outcome was 5-year overall survival (OS). RESULTS: A total of 167,606 patients were included. Following propensity-score matching 26,662 patients remained in each group (right-colon, left-colon, and rectum). 5-year OS was significantly worse for patients with Duke's A-C right-sided primaries compared to left-sided and rectal cancers in the unmatched (58.8% vs 66.7% vs 70.0% p=<0.001) and matched cohorts (62.6%, 66.8%, 65.8% p=<0.001). Superior OS for patients with left-sided colon cancer was demonstrated across all stages (Duke's A HR 0.845, p = 0.003; Duke's B HR 0.947, p = 0.045; Duke's C HR 0.783, p < 0.0001). Secondary analysis demonstrated equivalent OS between study groups when ≥22 lymph nodes were harvested. CONCLUSION: There is a significant difference in survival between comparable patients with right and left sided colon cancers in England. The quality and/or extent of mesenteric resection may be of particular importance in right-sided colon cancer.

Characteristics of High-Volume Lung Segmentectomy Hospitals: A Propensity Score-Matched Analysis.

BACKGROUND: Segmental resection continues to gain favor in the treatment of early-stage non-small cell lung cancer, but there is limited data on outcomes as related to facility volume. The purpose of this study is to better define the relationship between segmentectomy outcomes, survival, and facility volume. METHODS: A retrospective cohort analysis was completed using the National Cancer Database. Patients with stage I disease undergoing segmentectomy 2004 to 2015 were included. Facility volume was determined per year; facilities performing higher than the median number of segmental resections were deemed high-volume and retained that classification for the remainder of the study. Propensity-score matching was used to compare 5-year survival and outcomes. RESULTS: Six hundred eighty-one centers performing 2481 segmentectomies were included. High-volume centers had higher utilization of minimally invasive approaches and lower conversion rates. There was no difference in readmission or 30-day mortality, but 90-day mortality differed between groups (1.2% vs. 2.6%, P = .03). High-volume centers were more likely to sample lymph nodes (88.5% vs. 80.7%, P < .01), and patients were less likely to have positives margins (1.3% vs. 2.7%, P = .03). Patients were no more likely to be upstaged based on facility volume (4.6% vs. 3.3%, P = .21). Overall, 5-year survival was better for patients treated at high-volume centers in the full cohort (69.5% vs. 66.4%, P = .014) but in propensity score-matched analysis this survival difference became non-significant (68.0% vs. 67.9% (P = .172). CONCLUSION: Segmentectomy performed at high-volume centers is associated with more frequent use of minimally invasive approach, more frequent negative margins, and improved 90-day survival.

Predictors and Outcomes of Minimally Invasive Surgery for Small Bowel Neuroendocrine Tumors : Minimally Invasive Surgery for SBNETs.

BACKGROUND: Open surgical resection with regional lymphadenectomy is the standard of care for small bowel neuroendocrine tumors (SBNETs). There is no consensus on the role of minimally invasive surgery (MIS). This study aims to evaluate the current national trends for MIS in treating SBNETs and its association with lymph node (LN) yield. METHODS: The National Cancer Database was queried for patients with Stage I-III SBNETs who underwent surgery from 2010-2017. Time trends were examined using the Cochran-Armitage test. Chi-square tests, t test, and multivariable logistic regression assessed associations of surgical approach with patient, clinical, and facility characteristics. Kaplan-Meier curves and propensity score weighted Cox proportional hazards model were used to examine survival. RESULTS: Of the 11,367 patients with Stage I-III SBNETs, 46.5% (N = 5,298) underwent MIS. From 2010-2017, the proportion of MIS increased from 35.6% to 57.7% (P < 0.001). Patients of Stage I disease (OR = 1.23), Caucasian race (OR = 1.18), private insurance (OR = 1.29), and higher volume centers (OR = 1.29) were more likely to undergo MIS (all P < 0.02). The average number of LN harvested in the MIS cohort was greater than in the open surgery cohort (13.3 vs 11.8 LN, P < 0.001). MIS patients had shorter length of stay by 2 days compared to open surgery (5.4 vs 7.6 days, P < 0.001). LN yield ≥ 8 was associated with better survival (HR = 0.77, P < 0.001). CONCLUSION: The utilization of a MIS approach to treat Stage I-III SBNETs has increased, especially at higher volume centers. We did not observe an inferior LN harvest with the MIS cohort compared to the open surgery cohort.