Are Metastatic Central Lymph Nodes (D3 volume) in right-sided Colon Cancer a Sign of Systemic Disease? A sub-group Analysis of an Ongoing Multicenter Trial.

OBJECTIVE: Assess outcomes of patients with right-sided colon cancer with metastases in the D3 volume after personalized surgery. BACKGROUND: Patients with central lymph node metastasis (D3-PNG) are considered to have a systemic disease with a poor prognosis. A 3-dimensional definition of the dissection volume allows the removal of all central nodes. MATERIALS AND METHODS: D3-PNG includes consecutive patients from an ongoing clinical trial. Patients were stratified into residual disease negative (D3-RDN) and residual disease positive (D3-RDP) groups. D3-RDN was further stratified into 4 periods to identify a learning curve. A personalized D3 volume (defined through arterial origins and venous confluences) was removed " en bloc" through medial-to-lateral dissection, and the D3 volume of the specimen was analyzed separately. RESULTS: D3-PNG contained 42 (26 females, 63.1 SD 9.9 y) patients, D3-RDN:29 (17 females, 63.4 SD 10.1 y), and D3-RDP:13 (9 females, 62.2 SD 9.7 y). The mean overall survival (OS) days were D3-PNG:1230, D3-RDN:1610, and D3-RDP:460. The mean disease-free survival (DFS) was D3-PNG:1023, D3-RDN:1461, and D3-RDP:74 days. The probability of OS/DFS were D3-PNG:52.1%/50.2%, D3-RDN:72.9%/73.1%, D3-RDP: 7.7%/0%. There is a significant change in OS/DFS in the D3-RDN from 2011-2013 to 2020-2022 (both P =0.046) and from 2014-2016 to 2020-2022 ( P =0.028 and P =0.005, respectively). CONCLUSION: Our results indicate that surgery can achieve survival in most patients with central lymph node metastases by removing a personalized and anatomically defined D3 volume. The extent of mesenterectomy and the quality of surgery are paramount since a learning curve has demonstrated significantly improved survival over time despite the low number of patients. These results imply a place for the centralization of this patient group where feasible.

Chemotherapy reduces long-term quality of life in recurrence-free colon cancer survivors (LaTE study)-a nationwide inverse probability of treatment-weighted registry-based cohort study and survey.

AIM: Stage III colon cancer is routinely treated with adjuvant chemotherapy, which causes significant short-term morbidity. Its effect on long-term quality of life (QoL) is poorly investigated. The aim of this study was to investigate long-term QoL after curative treatment for colon cancer and explore the impact of chemotherapy on general and disease-specific QoL. METHOD: All patients aged under 75 years operated on for colon cancer between 30 September 2007 and 1 October 2019 were identified by the Cancer Registry of Norway. Exclusion criteria were distant metastasis, recurrence, dementia and rectal/rectosigmoid cancer operation. The primary outcome measure was Gastrointestinal Quality of Life Index (GIQLI). Secondary outcome measures included the Short Form Health Survey (SF-36). To achieve balanced groups when assessing differences in outcome measures the analyses were weighted by inverse probability weights based on a multiple logistic regression model with prechosen confounders. RESULTS: A total of 8627 patients were invited and 3109 responded (36% response rate). After exclusions 3025 patients were included, of whom 1148 (38%) had received adjuvant chemotherapy and 1877 (62%) had surgery alone, with mean follow-up of 75.5 versus 74.5 months, respectively. The GIQLI differed significantly between the groups [mean 111.0 (SD 18.4) vs. 115.6 (SD 17.8), respectively; mean difference: -4.6 (95% CI -5.9; -3.2); p < 0.001]. Those with the highest neurotoxicity exhibited the lowest GIQLI. The adjuvant chemotherapy group scored significantly lower in six of eight SF-36 domains compared with the surgery alone group. The main differences were found in social, physical and emotional function. CONCLUSION: Long-term QoL was significantly lower in patients who received adjuvant chemotherapy than in patients who did not. Neurotoxicity was closely related to reduced QoL in these patients. The low response rate limits the generalizability of the results.

Inadvertent laparoscopic lavage of perforated colon cancer: a systematic review.

BACKGROUND: Although laparoscopic lavage for perforated diverticulitis with peritonitis has been grabbing the headlines, it is known that the clinical presentation of peritonitis can also be caused by an underlying perforated carcinoma. The aim of this study was to determine the incidence of patients undergoing inadvertent laparoscopic lavage of perforated colon cancer as well as the delay in cancer diagnosis. METHODS: The PubMed database was systematically searched to include all studies meeting inclusion criteria. Studies were screened through titles and abstracts with potentially eligible studies undergoing full-text screening. The primary endpoints of this meta-analysis were the rates of perforated colon cancer patients having undergone inadvertent laparoscopic lavage as well as the delay in cancer diagnosis. This was expressed in pooled rate % and 95% confidence intervals. RESULTS: Eleven studies (three randomized, two prospective, six retrospective) totaling 642 patients met inclusion criteria. Eight studies reported how patients were screened for cancer and the number of patients who completed follow-up. The pooled cancer rate was 3.4% (0.9%, 5.8%) with low heterogeneity (Isquare2 = 34.02%) in eight studies. Cancer rates were 8.2% (0%, 3%) (Isquare2 = 58.2%) and 1.7% (0%, 4.5%) (Isquare2 = 0%) in prospective and retrospective studies, respectively. Randomized trials reported a cancer rate of 7.2% (3.1%, 11.2%) with low among-study heterogeneity (Isquare2 = 0%) and a median delay to diagnosis of 2 (1.5-5) months. CONCLUSIONS: This systematic review found that 7% of patients undergoing laparoscopic lavage for peritonitis had perforated colon cancer with a delay to diagnosis of up to 5 months.

Prognostic Impact of Resection Margin Status in Distal Pancreatectomy for Ductal Adenocarcinoma.

BACKGROUND: Resection margin status is considered one of the few surgeon-controlled parameters affecting prognosis in pancreatic ductal adenocarcinoma (PDAC). While studies mostly focus on resection margins in pancreatoduodenectomy, little is known about their role in distal pancreatectomy (DP). This study aimed to investigate resection margins in DP for PDAC. METHODS: Patients who underwent DP for PDAC between October 2004 and February 2020 were included (n = 124). Resection margins and associated parameters were studied in two consecutive time periods during which different pathology examination protocols were used: non-standardized (period 1: 2004-2014) and standardized (period 2: 2015-2020). Microscopic margin involvement (R1) was defined as ≤1 mm clearance. RESULTS: Laparoscopic and open resections were performed in 117 (94.4%) and 7 (5.6%) patients, respectively. The R1 rate for the entire cohort was 73.4%, increasing from 60.4% in period 1 to 83.1% in period 2 (p = 0.005). A significantly higher R1 rate was observed for the posterior margin (35.8 vs. 70.4%, p < 0.001) and anterior pancreatic surface (based on a 0 mm clearance; 18.9 vs. 35.4%, p = 0.045). Pathology examination period, poorly differentiated PDAC, and vascular invasion were associated with R1 in the multivariable model. Extended DP, positive anterior pancreatic surface, lymph node ratio, perineural invasion, and adjuvant chemotherapy, but not R1, were significant prognostic factors for overall survival in the entire cohort. CONCLUSIONS: Pathology examination is a key determinant of resection margin status following DP for PDAC. A high R1 rate is to be expected when pathology examination is meticulous and standardized. Involvement of the anterior pancreatic surface affects prognosis.

Establishing correlations between normal pancreatic and submandibular gland ducts.

BACKGROUND: The objectives of this study were to evaluate the relationship between ductal morphometry and ramification patterns in the submandibular gland and pancreas in order to validate their common fractal dimension. METHODS: X-ray ductography with software-aided morphometry were obtained by injecting barium sulphate in the ducts of post-mortem submandibular gland and pancreas specimens harvested from 42 adult individuals. RESULTS: Three cases were excluded from the study because of underlying pathology. There was a significant correlation between the length of the main pancreatic duct (MPD) and the intraglandular portion of the right submandibular duct (SMD) (r = 0.3616; p = 0.028), and left SMD (r = 0.595; p < 0.01), respectively, but their maximal diameters did not correlate (r = 0.139-0.311; p > 0.05). Both dimensions of the SMD showed a significant right-left correlation (p < 0.05). The number of MPD side branches (mean = 37) correlated with the number of side branches of left SMD, but not with the right one (mean = 9). Tortuosity was observed in 54% of the MPD, 32% of the right SMD, and 24% of the left SMD, with mutual association only between the two salivary glands. CONCLUSIONS: Although the length of intraglandular SMD and MPD correlate, other morphometric ductal features do not, thus suggesting a more complex relationship between the two digestive glands.

Re-interpreting mesenteric vascular anatomy on 3D virtual and/or physical models, part II: anatomy of relevance to surgeons operating splenic flexure cancer.

BACKGROUND: The splenic flexure is irrigated from two vascular areas, both from the middle colic and the left colic artery. The challenge for the surgeon is to connect these two vascular areas in an oncological safe procedure. MATERIALS AND METHODS: The vascular anatomy, manually 3D reconstructed from 32 preoperative high-resolution CT datasets using Osirix MD, Mimics Medical and 3-matic Medical Datasets, were exported as STL-files, video clips, stills and supplemented with 3D printed models. RESULTS: Our first major finding was the difference in level between the middle colic and the inferior mesenteric artery origins. We have named this relationship a mesenteric inter-arterial stair. The middle colic artery origin could be found cranial (median 3.38 cm) or caudal (median 0.58 cm) to the inferior mesenteric artery. The lateral distance between the two origins was 2.63 cm (median), and the straight distance 4.23 cm (median). The second finding was the different trajectories and confluence pattern of the inferior mesenteric vein. This vein ended in the superior mesenteric/jejunal vein (21 patients) or in the splenic vein (11 patients). The inferior mesenteric vein confluence could be infrapancreatic (17 patients), infrapancreatic with retropancreatic arch (7 patients) or retropancreatic (8 patients). Lastly, the accessory middle colic artery was present in ten patients presenting another pathway for lymphatic dissemination. CONCLUSION: The IMV trajectory when accessible, is the solution to the mesenteric inter-arterial stair. The surgeon could safely follow the IMV to its confluence. When the IMV trajectory is not accessible, the surgeon could follow the caudal border of the pancreas.

Re-interpreting mesenteric vascular anatomy on 3D virtual and/or physical models: positioning the middle colic artery bifurcation and its relevance to surgeons operating colon cancer.

BACKGROUND: The impact of the position of the middle colic artery (MCA) bifurcation and the trajectory of the accessory MCA (aMCA) on adequate lymphadenectomy when operating colon cancer have as of yet not been described and/or analysed in the literature. The aim of this study was to determine the MCA bifurcation position to anatomical landmarks and to assess the trajectory of aMCA. METHODS: The colonic vascular anatomy was manually reconstructed in 3D from high-resolution CT datasets using Osirix MD and 3-matic Medical and analysed. CT datasets were exported as STL files and supplemented with 3D printed models when required. RESULTS: Thirty-two datasets were analysed. The MCA bifurcation was left to the superior mesenteric vein (SMV) in 4 (12.1%), in front of SMV in 17 (53.1%) and right to SMV in 11 (34.4%) models. Median distances from the MCA origin to bifurcation were 3.21 (1.18-15.60) cm. A longer MCA bifurcated over or right to SMV, while a shorter bifurcated left to SMV (r = 0.457, p = 0.009). The main MCA direction was towards right in 19 (59.4%) models. When initial directions included left, the bifurcation occurred left to or anterior to SMV in all models. When the initial directions included right, the bifurcation occurred anterior or right to SMV in all models. The aMCA was found in 10 (31.3%) models, following the inferior mesenteric vein (IMV) in 5 near the lower pancreatic border. The IMV confluence was into SMV in 18 (56.3%), splenic vein in 11 (34.4%) and jejunal vein in 3 (9.4%) models. CONCLUSION: Awareness of the wide range of MCA bifurcation positions reported is crucial for the quality of lymphadenectomy performed. The aMCA occurs in 31.3% models and its trajectory is in proximity to the lower pancreatic border in one half of models, indicating that it needs to be considered when operating splenic flexure cancer.

Reconstructing topography and extent of injury to the superior mesenteric artery plexus in right colectomy with extended D3 mesenterectomy: a composite multimodal 3-dimensional analysis.

BACKGROUND: Superior mesenteric artery plexus (SMAP) injury is reported to cause postoperative intractable diarrhea after pancreatic/colonic surgery with extended lymphadenectomy. This study aims to describe the SMAP microanatomy and extent of injury after right colectomy with extended D3 mesenterectomy for cancer. METHODS: Three groups (I) anatomical dissection, (II) postmortem histology, and (III) surgical specimen histology were included. Nerve count and area were compared between groups II and III and paravascular sheath thickness between groups I and II. 3D models were generated through 3D histology, nanoCT scanning, and finally through 3D printing. RESULTS: A total of 21 specimens were included as follows: Group (I): 5 (3 females, 80-93 years), the SMAP is a complex mesh surrounding the superior mesenteric artery (SMA), branching out, following peripheral arteries and intertwining between them, (II): 7 (5 females, 71-86 years), nerve count: 53 ± 12.42 (38-68), and area: 1.84 ± 0.50 mm2 (1.16-2.29), and (III): 9 (5 females, 55-69 years), nerve count: 31.6 ± 6.74 (range 23-43), and area: 0.889 ± 0.45 mm2 (range 0.479-1.668). SMAP transection injury is 59% of nerve count and 48% of nerve area at middle colic artery origin level. The median values of paravascular sheath thickness decreased caudally from 2.05 to 1.04 mm (anatomical dissection) and from 2.65 to 1.17 mm (postmortem histology). 3D histology models present nerve fibers exclusively within the paravascular sheath, and lymph nodes were observed only outside. NanoCT-derived models reveal oblique nerve fiber trajectories with inclinations between 35° and 55°. Two 3D-printed models of the SMAP were also achieved in a 1:2 scale. CONCLUSION: SMAP surrounds the SMA and branches within the paravascular sheath, while bowel lymph nodes and vessels lie outside. Extent of SMAP injury on histological slides (transection only) was 48% nerve area and 59% nerve count. The 35°-55° inclination range of SMAP nerves possibly imply an even larger injury when plexus excision is performed (lymphadenectomy). Reasons for later improvement of bowel function in these patients can lie in the interarterial nerve fibers between SMA branches.

Implementation and training with laparoscopic distal pancreatectomy: 23-year experience from a high-volume center.

BACKGROUND: Distal pancreatectomy is the most common procedure in minimally-invasive pancreatic surgery. Data in the literature suggest that the learning curve flattens after performing up to 30 procedures. However, the exact number remains unclear. METHODS: The implementation and training with laparoscopic distal pancreatectomy (LDP) in a high-volume center were studied between 1997 and 2020. Perioperative outcomes and factors related to conversion were assessed. The individual experiences of four different surgeons (pioneer and adopters) performing LDP on a regular basis were examined. RESULTS: Six hundred forty LDPs were done accounting for 95% of all distal pancreatectomies performed throughout the study period. Conversion was needed in 14 (2.2%) patients due to intraoperative bleeding or tumor adherence to the major vasculature. Overall morbidity and mortality rates were 35 and 0.6%, respectively. Intra- and postoperative outcomes did not change for any of the surgeons within their first 40 cases. Operative time significantly decreased after the first 80 cases for the pioneer surgeon and did not change afterwards although the proportion of ductal adenocarcinoma increased. Tumor size increased after the first 80 cases for the first adopter without affecting the operative time. CONCLUSIONS: In this nearly unselected cohort, no significant changes in surgical outcomes were observed throughout the first 40 LDPs for different surgeons. The exact number of procedures required to overcome the learning curve is difficult to determine as it seems to depend on patient selection policy and specifics of surgical training at the corresponding center.

The Use of a Vascular Roadmap at Surgery Evens out Surgeons Expectations on Operating Time, Blood Loss, Lymph Nodes Harvest and Operative Difficulty when Performing Right Colectomy with Extended D3 Mesenterectomy.

PURPOSE: To determine how individual vascular road-mapping impacts the surgeonsâ?? expectations in difficulty in D3 right colectomy for cancer, and compare these expectations to the results previously published. Aim/summary background data:Literature still lacks data on surgeons expectations using preoperative 3D roadmap of the vascular system. METHOD: Surgeons filled out a survey asking expectations about operation time, estimated blood loss, amount of lymph nodes harvested and difficulty. The patients were classified into 4 groups and 2 subgroups according to the crossing pattern of the ileocolic artery and the jejunal veins. SPSS was used for statistical analysis. Results: Twelve surgeons were included. Eight of them expected type 2 anatomy to be least time consuming while 11/12 indicated anatomy group 4 to be the most. Five surgeons expected low blood loss in group 2 anatomy patients while 10/12 expected higher blood loss in group 4 anatomy patients. Three anticipated that group 2 would generate the highest lymph node yield and while 2/12 surgeons expected the lowest in anatomy group 4. Eight surgeons perceived group 2 as the least challenging while 10/12 experienced group 4 as the most difficult. Compared to previously published results only group 4b operating time met surgeons expectations. CONCLUSION: Using a vascular roadmap at surgery evens out surgeons expectations in operation time, blood loss, lymph node harvested and difficulty. Comparing expectations to previously published data shows operating time in one anatomy group as the only factor where these expectations were met.

Stool dynamics after extrinsic nerve injury during right colectomy with extended D3-mesenterectomy.

INTRODUCTION: To improve oncological outcome in right colon cancer surgery, an extended mesenterectomy (D3) is under evaluation. In this procedure, all tissue anterior and posterior to the superior mesenteric vessels from the middle colic to ileocolic artery origin is removed, causing injury to the superior mesenteric nerve plexus. The aim was to study the effects of this injury on bowel dynamics and quality of life (QoL). METHODS: Patients undergoing right colectomy with conventional D2- and extended D3-mesenterectomy were asked to record stool number and consistency for 60 d after surgery and complete questionnaires regarding QoL and bowel function (BF) before and after recovery from surgery. We compared early postoperative stool dynamics and long-term QoL in the groups and presented graphs depicting the temporal profile of stool numbers and consistency. RESULTS: Thirty-three patients operated with a D3-resection and 12 patients with a D2-resection participated. The results revealed significantly higher stool numbers in the D3-group until day 26, with significantly more loose-watery stools until day 40. The most pronounced difference was found on day 9 (Mean difference in the total number of stools: 2.25 stools/day, p=.004. Mean difference in loose-watery stools/day: 2.81 p<.001). About 25% in the D2- and 69.7% in the D3-group reported having more than three stools/day in the early postoperative phase. There were no differences in long-term QoL and BF between the groups except in stool consistency (p=.039). DISCUSSION/CONCLUSIONS: Denervation following extended D3-mesenterectomy leads to transitory reduced consistency and increased frequency. It does not affect long-term QoL or BF.

Video-based coaching in surgical education: a systematic review and meta-analysis.

BACKGROUND: In the era of competency-based surgical education, VBC has gained increased attention and may enhance the efficacy of surgical education. The objective of this systematic review was to summarize the existing evidence of video-based coaching (VBC) and compare VBC to traditional master-apprentice-based surgical education. METHODS: We performed a systematic review and meta-analysis of randomized controlled trials (RCT) assessing VBC according to the PRISMA and Cochrane guidelines. The MEDLINE, EMBASE, and COCHRANE and Researchgate databases were searched for eligible manuscripts. Standard mean difference (SMD) of performance scoring scales was used to assess the effect of VBC versus traditional training without VBC (control). RESULTS: Of 627 studies identified, 24 RCTs were eligible and evaluated. The studies included 778 surgical trainees (n = 386 VBC vs. n = 392 control). 13 performance scoring scales were used to assess technical competence; OSATS-GRS was the most common (n = 15). VBC was provided preoperative (n = 11), intraoperative (n = 1), postoperative (n = 10), and perioperative (n = 2). The majority of studies were unstructured, where identified coaching frameworks were PRACTICE (n = 1), GROW (n = 2) and Wisconsin Coaching Framework (n = 1). There was an effect on performance scoring scales in favor of VBC coaching (SMD 0.87, p < 0.001). In subgroup analyses, the residents had a larger relative effect (SMD 1.13; 0.61-1.65, p < 0.001) of VBC compared to medical students (SMD 0.43, 0.06-0.81, p < 0.001). The greatest source of potential bias was absence of blinding of the participants and personnel (n = 20). CONCLUSION: Video-based coaching increases technical performance of medical students and surgical residents. There exist significant study and intervention heterogeneity that warrants further exploration, showing the need to structure and standardize video-based coaching tools.

Semi-automated vs. manual 3D reconstruction of central mesenteric vascular models: the surgeon's verdict.

BACKGROUND: 3D vascular anatomy roadmaps are currently being implemented for surgical planning and navigation. Quality of the reconstruction is critical. The aim of this article is to compare anatomical completeness of models produced by manual and semi-automatic segmentation. METHODS: CT-datasets from patients included in an ongoing trial, underwent 3D vascular reconstruction applying two different segmentation methods. This produced manually-segmented models (MSMs) and semi-automatically segmented models (SAMs) which underwent a paired comparison. Datasets were delivered for reconstruction in 4 batches of 6, of which only batch 4 contained patients with abnormal anatomy. Model completeness was assessed quantitatively using alignment and distance error indexes and qualitatively with systematic inspection. MSMs were the gold standard. Assessed vessels were those of interest to the surgeon performing D3-right colectomy. RESULTS: 24 CT-datasets (13 females, age 44-77) were used in a paired comparative analysis of 48 3D-models. Quantitatively, SAMs showed structural improvement from Batch 1 to 3. Batch 4, with abnormal vessels, showed the highest error-index values. Qualitatively, 91.7% of SAMs did not contain all mesenteric branches relevant to the surgeon. In SAMs, 1 (12.5%) right colic artery-RCA scored as a complete vessel. 3 (37.5%) RCAs scored as incomplete and 4 (50%) RCAs were absent. 6 (25%) of 24 middle colic arteries-MCA scored as complete vessels. 11 (45.8%) scored as incomplete while 7 (29.2%) MCAs were absent. 13 (54.2%) of 24 ileocolic arteries-ICA were complete vessels. 11 (45.8%) scored as incomplete. None (0%) were absent. Additionally, it was observed that 10 (41.7%) of SAMs contained all their jejunal arteries, when compared to MSMs. Calibers of "complete" vessels were significantly higher than in "missing" vessels (MCA p < 0.001, RCA p = 0.016, ICA p < 0.001, JAs p < 0.001). CONCLUSION: Despite acceptable results from quantitative analysis, qualitative comparison indicates that semi-automatically generated 3D-models of the central mesenteric vasculature could cause considerable confusion at surgery.

Surgical challenges and research priorities in the era of the COVID-19 pandemic: EAES membership survey.

BACKGROUND: Healthcare systems and general surgeons are being challenged by the current pandemic. The European Association for Endoscopic Surgery (EAES) aimed to evaluate surgeons' experiences and perspectives, to identify gaps in knowledge, to record shortcomings in resources and to register research priorities. METHODS: An ad hoc web-based survey of EAES members and affiliates was developed by the EAES Research Committee. The questionnaire consisted of 69 items divided into the following sections: (Ι) demographics, (II) institutional burdens and management strategies, and (III) analysis of resource, knowledge, and evidence gaps. Descriptive statistics were summarized as frequencies, medians, ranges,, and interquartile ranges, as appropriate. RESULTS: The survey took place between March 25th and April 16th with a total of 550 surgeons from 79 countries. Eighty-one percent had to postpone elective cases or suspend their practice and 35% assumed roles not related to their primary expertise. One-fourth of respondents reported having encountered abdominal pathologies in COVID-19-positive patients, most frequently acute appendicitis (47% of respondents). The effect of protective measures in surgical or endoscopic procedures on infected patients, the effect of endoscopic surgery on infected patients, and the infectivity of positive patients undergoing laparoscopic surgery were prioritized as knowledge gaps and research priorities. CONCLUSIONS: Perspectives and priorities of EAES members in the era of the pandemic are hereto summarized. Research evidence is urgently needed to effectively respond to challenges arisen from the pandemic.

Preventing chylous ascites after right hemicolectomy with D3 extended mesenterectomy.

BACKGROUND: We aim to find the incidence of chylous ascites in patients undergoing D3 extended mesenterectomy and evaluate if a routine fat-reduced diet (FRD) has a prophylactic effect. METHODS: Data from 138 patients included in a D3 extended mesenterectomy trial were collected prospectively. Surgical drains and biochemical testing of drain fluid were used to find the incidence of chylous ascites among the first 39 patients, and a prophylactic fat-reduced diet was then implemented in the next 99 patients as a prophylactic measure. RESULTS: In the first 39 patients, we found that 16 (41.0%) developed chylous ascites. After the fat-reduced diet was implemented, 1 (1.0%) of 99 patients developed chylous ascites. Drain discharge was 150 vs. 80 mL daily, respectively, and a regression analysis shows the average leakage in the group with fat-reduced diet was 105 mL/day less than in the patients with no dietary restrictions (p < 0.001). There were no significant differences in the rate of other complications (Fisher exact test, one-tailed p = 0.8845), and although there was a tendency to a shorter hospital stay when given a fat-reduced diet (7.3 ± 5.4 vs. 8.9 ± 4.9 days), the difference was not significant (p = 0.19). CONCLUSIONS: Chylous ascites is a very common postoperative occurrence after right colectomy with extended D3 mesenterectomy and may be prevented using a routine fat-reduced diet.

Bowel Motility After Injury to the Superior Mesenteric Plexus During D3 Extended Mesenterectomy.

BACKGROUND: Improvement of lymphadenectomy in right colectomy requires removal of all tissue surrounding the superior mesenteric vessels beneath the pancreatic notch. Short- and long-term bowel motility disorders after D3 extended mesenterectomy with consecutive superior mesenteric plexus transection are studied. METHODS: Patients without pre-existing motility disorders undergoing D3 extended mesenterectomy were examined 3 times using the wireless motility capsule: before, at 3 wk, and 6 mo after surgery. Segmental transit times and contractility were analyzed using mixed effect modeling. Correlation between contractility and transit time was assessed by the Pearson correlation coefficient. RESULTS: Fifteen patients (4 men), with median age 62 y, were included. Mean values for the three consecutive examinations are as follows. Gastric transit time increased from 237 to 402 and 403 min, respectively. Small bowel transit time decreased from 246 to 158 (P < 0.01) and 199 (P = 0.03) min, respectively. Colonic transit time decreased from 1742 to 1450 and 1110 (P = 0.02) min, respectively. Gastric contractions per minute (CPM) varied from 1.73 to 1.05 (P = 0.01) and 2.47 (P < 0.01), respectively. Small bowel CPM decreased from 3.43 to 2.68 and 3.34, respectively. Colonic CPM ranged from 1.59 to 1.45 and 1.91 (P = 0.08), respectively. Correlation between small bowel (SB) transit time and CPM was -0.45 (P = 0.09) preoperatively, and -0.03 (P = 0.91) 6 mo postoperatively. CONCLUSIONS: Extrinsic SB denervation leads to significantly accelerated SB transit, reduced contractility, and disturbed correlation between transit time and contractility early after denervation. Both number of contractions and transit time in the denervated SB show a clear tendency toward normalization at 6 mo.

Preoperative anatomical road mapping reduces variability of operating time, estimated blood loss, and lymph node yield in right colectomy with extended D3 mesenterectomy for cancer.

OBJECTIVE: To assess the impact of individual patient anatomy on operating time, estimated blood loss (EBL), and lymph node yield in right colectomy with extended D3 mesenterectomy, where surgeons have access to a preoperative 3-D reconstruction of the vascular anatomy of patients before surgery. Data on the impact of individual patient vascular anatomy when surgeons have an anatomical road map as a guide at surgery is still missing in the literature. METHOD: Consecutive patients enrolled in an ongoing trial were classified into 4 groups and 2 subgroups using a 3-D vascular anatomy reconstruction derived from the staging CT. Outcome measures are operating time, EBL, vascular events, and D3 volume lymph node yield. SPSS was used for statistical analysis. RESULTS: One hundred seventy-six (77 men) patients included. Mean operating time was 200 ± 50 min. Type 4b required significantly longer operating time (mean, 219 ± 59) compared to type 3 (mean, 188 ± 43) (p = 0.004). Vascular events occurred most often in anatomy type 4b (20.0%) and 3 (19.2%). No difference in EBL and lymph node yield was found (p = 0.102 and p = 0.803, respectively). CONCLUSION: The use of a roadmap at surgery seems to even differences in operating time, EBL, and lymph node yield, independent of the complexity of the individual patient's central mesenteric vascular anatomy. The incidents of vascular events requiring hemostasis do not cause differences in EBL between the anatomy groups, suggesting that preoperative awareness of the anatomy is beneficial at surgery.

Implementation of 3D printed superior mesenteric vascular models for surgical planning and/or navigation in right colectomy with extended D3 mesenterectomy: comparison of virtual and physical models to the anatomy found at surgery.

BACKGROUND: Three-dimensional (3D) printing technology has recently been well approved as an emerging technology in various fields of medical education and practice; e.g., there are numerous studies evaluating 3D printouts of solid organs. Complex surgery such as extended mesenterectomy imposes a need to analyze also the accuracy of 3D printouts of more mobile and complex structures like the diversity of vascular arborization within the central mesentery. The objective of this study was to evaluate the linear dimensional anatomy landmark differences of the superior mesenteric artery and vein between (1) 3D virtual models, (2) 3D printouts, and (3) peroperative measurements. METHODS: The study included 22 patients from the ongoing prospective multicenter trial "Safe Radical D3 Right Hemicolectomy for Cancer through Preoperative Biphasic MDCT Angiography," with preoperative CT and peroperative measurements. The patients were operated in Norway between January 2016 and 2017. Their CT datasets underwent 3D volume rendering and segmentation, and the virtual 3D model produced was then exported for stereolithography 3D printing. RESULTS: Four parameters were measured: distance between the origins of the ileocolic and the middle colic artery, distance between the termination of the gastrocolic trunk and the ileocolic vein, and the calibers of the middle colic and ileocolic arteries. The inter-arterial distance has proven a strong correlation between all the three modalities implied (Pearson's coefficient 0.968, 0.956, 0.779, respectively), while inter-venous distances showed a weak correlation between peroperative measurements and both virtual and physical models. CONCLUSION: This study showed acceptable dimensional inter-arterial correlations between 3D printed models, 3D virtual models and authentic soft tissue anatomy of the central mesenteric vessels, and weaker inter-venous correlations between all the models, reflecting the highly variable nature of veins in situ.

Right Colectomy with Extended D3 Mesenterectomy: Anterior and Posterior to the Mesenteric Vessels.

BACKGROUND: In right colectomy for cancer, complete mesocolic excision and D3 lymphadenectomy each leave behind lymphatic tissue anterior and posterior to the superior mesenteric vein (SMV) and artery (SMA). In this article, we present D3 extended mesenterectomy: a surgical technique that excises the lymphatic tissue en bloc with the right colectomy specimen. MATERIAL AND METHODS: A 3D map of the mesentery of the right colon was reconstructed from staging CT-angiogram scans. The surgical technique of right colectomy with D3 extended mesenterectomy consisted of eight steps: 1) reveal the SMV and SMA; 2) isolate the ileocolic artery; 3) isolate the middle colic artery; 4) resolve the anterior mesenteric flap; 5) specimen de-vascularization; 6) colectomy; 7) resolve the posterior mesenteric flap; and 8) anastomosis. RESULTS: One-hundred-seventy-six patients (77 men) 66 years of age were operated upon from February 2011 to January 2017. There were 169 adenocarcinomas: 16.0% Stage I, 49.1% Stage II, 33.7% Stage III, 1.2% Stage IV. Tumor locations were 50.6% cecum, 41.5% ascending colon, 4.5% hepatic flexure, and 2.3% transverse colon. Mean operating time was 200 minutes, blood loss 273 ml, and length of stay 7.9 days. There were 9 anastomotic leakages and 15 reoperations. One patient underwent small bowel resection due to SMA tear. There was no postoperative mortality. The mean number of lymph nodes per specimen (40.9) was comprised of 27.1 in the D2 volume and 13.8 in the D3 volume. The mean number of metastatic lymph nodes was 1.2 in the D2 volume and 0.13 in D3. There were 7 patients with lymph node metastasis in D3, 2 of whom had node metastasis solely within D3. CONCLUSION: This study shows that 1.2% of patients would have been incorrectly diagnosed as Stage II if extended D3 mesenterectomy had not been performed. Similarly, lymph node metastases would have been left behind in 4.1% of patients if extended D3 mesenterectomy had not been performed.