Vascular anatomy of the transverse mesocolon and bidirectional laparoscopic D3 lymph node dissection for patients with advanced transverse colon cancer

Usefulness of intraoperative ultrasound examination for laparoscopic right-side colon cancer surgery: a propensity score-matched study

Complete mesocolic excision (CME) with central vascular ligation (CVL) in laparoscopic surgery for right-sided colon cancer (RSCC) requires a precise understanding of the vascular anatomy. The efficacy of intraoperative ultrasound (IUS) in the identification of blood vessels for RSCC surgery was not evaluated. The aim of this study was to compare the intraoperative and short-term outcomes of CME with CVL with or without IUS by laparoscopic surgery for RSCC. We performed IUS on 26 patients of RSCC and compared with a total of 124 patients who underwent the surgery for RSCC at our institution. Propensity score matching (PSM) was performed to reduce the confounding effects to imbalances in the use of IUS. The IUS identified the main feeding artery and the accompanying vein in all 26 cases. After PSM, the amount of intraoperative blood loss in the IUS group was significantly lower than that in the conventional group (5 ml vs. 30 ml, p = 0.035) and no significant difference of the postoperative complications was observed. The IUS reduced the risk of bleeding in the surgery for RSCC. The IUS is a safe and feasible technique that help the surgeons for anatomical understandings under real-time condition in the laparoscopic surgery of RSCC.

A multicenter prospective observational study of lymph node metastasis patterns and short-term outcomes of extended lymphadenectomy in right-sided colon cancer

Background

The lymph node metastasis rate in right-sided colon cancer is unknown, and the optimal central vascular ligation level remains controversial. We aimed to determine the lymph node metastasis rate and short-term results of radical surgery with extended lymph node dissection in right-sided colon cancer.

Methods

This prospective multicenter observational study included patients with stage II/III right-sided colon cancer from five cancer hospitals. The metastasis rate of each node station was analyzed according to tumor location and main feeding artery.

Results

Between April 2018 and August 2021, 208 patients underwent dissection around the superior mesenteric artery (SMA) and vein (SMV). In transverse colon cancer, 7.5% and 2.5% of metastases occurred around the SMV and SMA at the root of the middle colic artery (MCA), respectively; 6.7% and 6.7% at the root of the right colic artery. In caecal cancer, 1.9% of metastases occurred around the SMV and 1.9% around the SMA. In ascending colon cancer, the rate was 1.1% around the SMV. Of the tumors, 17% fed mainly by the ileocolic artery had node metastases along the middle or right colic artery, as did 66.7% fed mainly by the right colic artery and 41.2% fed by the MCA (p = 0.01). Postoperative complications occurred in 42 patients (20.2%).

Conclusion

Routine prophylactic extended lymphadenectomy around the SMA might not be necessary in caecum and ascending colon cancer. Dissection around the SMA may be necessary in cases of transverse colon cancer or when the feeding artery is the MCA.

Cadaveric and CT angiography study of vessels around the transverse colon mesentery

BACKGROUND

Laparoscopic and robotic surgery for transverse colon cancer are difficult due to complex fusion of the foregut and midgut and variation of the vessels of the transverse colon. Although the vessels of the right colon have been investigated, middle colic artery (MCA) variation and the relationship with vessels around the transvers colon are unknown. We investigated variation of the MCA using computed tomography angiography (CTA) and cadaver specimen and the relationship between the superior mesenteric vein (SMV) and MCA using CTA. The classification of vessels around the transverse colon may lead to safer and reliable surgery.

METHODS

This study included 505 consecutive patients who underwent CTA in our institution from 2014 to 2020 and 44 cadaver specimens. Vascular anatomical classifications and relationships were analyzed using CT images.

RESULTS

The MCA was defined as the arteries arising from the superior mesenteric artery (SMA) that flowed into the transverse colon at the distal ends. The classifications were as follows: type I, branching right and left from common trunk; type II, the right and left branches bifurcated separately from the SMA; and type III, the MCA branched from a vessel other than the SMA. Type II was subclassified into two subtypes, type IIa with one left branch and type IIb with two or more left branches from SMA. In the CTA and cadaver studies, respectively, the classifications were as follows: type I, n = 290 and n = 31; type IIa, n = 211 and n = 13; type IIb, n = 3 and n = 0; and type III, n = 1 and n = 0. We classified the relationship between the MCA and left side of the SMV into three types: type A, a common trunk runs along the left edge of the SMV (n = 173; 59.7%); type B, a right branch of the MCA runs along the left edge of the SMV (n = 116; 40.0%); and type C, the MCA runs dorsal of the SMV (n = 1; 0.3%).

CONCLUSIONS

This study revealed that The MCA branching classifications and relationship between the SMV and MCA. Preoperative CT angiography may be able to reliably identify vessel variation, which may be useful in clinical practice.

Vascular variations encountered during laparoscopic surgery for transverse colon, splenic flexure, and descending colon cancer: a retrospective cohort study

BACKGROUND

Laparoscopic surgery for cancer located in the transverse colon or splenic flexure is difficult because of vascular variability in this region and adjacent vital organs such as the pancreas, spleen, and duodenum.

METHODS

This retrospective cohort study involved 51 patients who underwent laparoscopic surgery for colon cancer at Tokushima University Hospital from July 2015 to December 2020. Variations of the middle colic artery (MCA), left colic artery (LCA), middle colic vein (MCV), and first jejunal vein (FJV) and short-term outcomes of laparoscopic surgery in patients with each vascular variation were evaluated.

RESULTS

Variations of the MCA, LCA, MCV, and FJV were classified into four, three, five, and three patterns, respectively. The short-term outcomes of laparoscopic surgery for transverse colon cancer in patients with MCA variations and those with FJV variations were evaluated, and no significant difference was found in the operation time, blood loss, postoperative complication rate, time from surgery to start of dietary intake, or time from surgery to discharge among the different variations. Additionally, no significant differences were found in the short-term outcomes of laparoscopic surgery for descending colon cancer in patients with LCA variations.

CONCLUSION

Preoperative assessment of vascular variations may contribute to the stability of short-term outcomes of laparoscopic surgery for transverse colon, splenic flexure, and descending colon cancer.

Surgical outcomes of various surgical approaches for transverse colon cancer

The transverse colon has anatomical peculiarities in the middle position between the foregut and the midgut. Because the transverse colon harbors a flexure at both ends, mobilization of the transverse colon can be especially challenging compared with other colons. Although transverse colon cancer is relatively uncommon, an optimal surgical management for transverse colon cancer must be established. In transverse colon cancer, proximity to the pancreas and variation in arterial and venous anatomy make radical resection more difficult. Dissection of lymph nodes around the middle colic vessels is a critical step in transverse colon cancer resection. The proximity of the middle colic vessels to the superior mesenteric vessels contributes to the complexity of this step, making it challenging for less-trained surgeons. For these reasons, patients with transverse colon cancer were not included in most landmark studies that compared laparoscopic surgery with open surgery. More radical operations, such as subtotal colectomy or extended right or left hemicolectomy, can be performed for transverse colon cancer to secure an adequate lymphadenectomy. Such cancers have also been treated with limited segmental colectomies, such as right, transverse, or left colectomy. Currently, there is still a lack of standardized definitions and procedures. Therefore, it is time to discuss and establish optimal surgical treatments for transverse colon cancer.

Vascular anatomy of the splenic flexure: a review of the literature

Surgical treatment of the transverse colon is difficult because of the many variations of blood vessels. We reviewed the patterns of vascular anatomy and the definition of the vessels around the splenic flexure. We searched the PubMed database for studies on the vascular anatomy of the splenic flexure that were published from January 1990 to October 2020. After screening of full texts, 33 studies were selected. The middle colic arteries were reported to arise independently without forming a common trunk in 8.9-33.3% of cases. The left colic artery was absent in 0-7.5% of cases. The accessory middle colic artery was present in 6.7-48.9% of cases and was present in > 80% of cases without a left colic artery. The reported frequency of Riolan's arch was 7.5-27.8%. The frequency was found to vary widely across studies, partially due to the ambiguous definition of Riolan's arch. A comprehensive preoperative knowledge of the branching patterns of the middle colic artery and left colic artery and the presence of collateral arteries would be helpful in surgery for colon cancer in the splenic flexure.

Surgical anatomy of the accessory middle colic artery: a meta-analysis with implications for splenic flexure cancer surgery

AIM

Surgical resection of splenic flexure cancers (SFCs) is technically demanding due to the complex regional anatomy, characterized by the presence of embryological adhesions, close proximity to the pancreas and spleen, and a highly heterogeneous arterial supply and lymphatic drainage. The accessory middle colic artery (AMCA) is increasingly being recognized as an important source of blood supply to the splenic flexure. The aim of this study is to determine the prevalence and anatomical features of the AMCA.

METHOD

A systematic search of the scientific literature was conducted on PubMed and Embase from inception to November 2020 to identify potentially eligible studies. Data were extracted and prevalence was pooled into a meta-analysis using MetaXL and Meta-Analyst software.

RESULTS

A total of 16 studies (n = 2203 patients) were included. The pooled prevalence (PP) of the AMCA was 25.4% (95% CI 18.1-33.4). Its prevalence was higher in patients without a left colic artery (LCA) (PP = 83.2%; 95% CI 70.4-93.1). The commonest origin for the AMCA was the superior mesenteric artery (PP = 87.9%; 95% CI 86.4-90.7). The AMCA shared a common trunk/gave rise to pancreatic branches in 23.1% of cases (95% CI 15.3-31.9).

CONCLUSION

The AMCA contributes to the vascularization of the splenic flexure in approximately 25% of individuals, and may be an important feeder artery to SFCs, especially in the absence of a LCA. Preoperative identification of this artery is important to ensure optimal surgery for SFC and minimize complications.

Securing the surgical field for mobilization of right-sided colon cancer using the duodenum-first multidirectional approach in laparoscopic surgery

Background

The aim of this study was to compare the short-term outcomes of the duodenum-first multidirectional approach (DMA) in laparoscopic right colectomy with those of the conventional medial approach to assess its safety and feasibility.

Methods

This retrospective study enrolled 120 patients who had laparoscopic surgery for right-sided colon cancer in our institution between April 2013 and December 2019. Fifty-four patients underwent colectomy using the multidirectional approach; among these, 20 underwent the DMA and 34 underwent the caudal-first multidirectional approach (CMA). Sixty-six patients underwent the conventional medial approach. Complications within 30 days of surgery were compared between the groups.

Results

There were 54 patients in the multidirectional group [29 females, median age 72 years (range 36–91 years)] and 66 in the medial group [42 females, median age 72 years (range 41–91 years)]. Total operative time was significantly shorter in multidirectional approach patients than conventional medial approach patients (208 min vs. 271 min; p = 0.01) and significantly shorter in patients who underwent the DMA compared to the CMA (201 min vs. 269 min; p < 0.001). Operative time for the mobilization procedure was also significantly shorter in patients who underwent the DMA (131 min vs. 181 min; p < 0.001). Blood loss and incidence of postoperative complications did not differ. In 77 patients with advanced T3/T4 tumors, the DMA, CMA, and conventional medial approach were performed in 13, 21, and 43 patients, respectively. Total operative time and operative time of the mobilization procedure were significantly shorter in patients undergoing DMA. Blood loss and incidence of postoperative complications did not differ. R0 resection was achieved in all patients with advanced tumors.

Conclusions

The DMA in laparoscopic right colectomy is safe and feasible and can achieve R0 resection with a shorter operative time than the conventional medial approach, even in patients with advanced tumors.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10151-021-02444-5.

Surgical Approach to Transverse Colon Cancer: Analysis of Current Practice and Oncological Outcomes Using the National Cancer Database

BACKGROUND

Surgical treatment for transverse colon cancer involves either extended colectomy or segmental resection, depending on the location of the tumor and surgeon perspective. However, the oncological safety of segmental resection has not yet been established in large cohort studies.

OBJECTIVE

This study aims to compare segmental resection versus extended colectomy for transverse colon cancer in terms of oncological outcomes.

DESIGN

This was a retrospective cohort study.

SETTINGS

This study was conducted using a nationwide cohort.

PATIENTS

A total of 66,062 patients who underwent colectomy with curative intent for transverse stage I to III adenocarcinoma were identified in the National Cancer Database (2004-2015).

MAIN OUTCOME MEASURES

Patients were divided in 2 groups based on the type of surgery received (extended versus segmental resection). The primary outcome was overall survival. Secondary outcomes were 30- and 90-day mortality, length of hospital stay, and readmission rate within 30 days of surgical discharge.

RESULTS

Extended colectomy was performed in 44,417 (67.2%) patients, whereas 21,645 (32.8%) patients underwent segmental resection. Extended colectomy was associated with lower survival at multivariate analysis (HR, 1.07; 95% CI, 1.04-1.10; p < 0.001). The subgroup analysis showed that extended resection was independently associated with poorer survival in mid transverse colon cancers (HR, 1.08; 95% CI, 1.04-1.12; p < 0.001) and in stage III tumors (HR, 1.11; 95% CI, 1.04-1.18; p < 0.001). The number of at least 12 harvested lymph nodes was an independent predictor of improved survival in both overall and subgroup analyses.

LIMITATIONS

This study was limited by its retrospective design.

CONCLUSION

Extended colectomy was not associated with a survival advantage compared with segmental resection. On the contrary, extended colectomy was associated with slightly poorer survival in mid transverse cancers and locally advanced tumors. Segmental resection was found to be safe when appropriate margins and adequate lymph node harvest were achieved. See Video Abstract at http://links.lww.com/DCR/B454.

ABORDAJE QUIRRGICO DEL CNCER DE COLON TRANSVERSO ANLISIS DE LA PRCTICA ACTUAL Y LOS RESULTADOS ONCOLGICOS UTILIZANDO LA BASE DE DATOS NACIONAL DE CNCER

ANTECEDENTES:El tratamiento quirúrgico para el cáncer de colon transverso implica colectomía extendida o resección segmentaria, según la ubicación del tumor y la perspectiva del cirujano. Sin embargo, la seguridad oncológica de la resección segmentaria aún no se ha establecido en estudios de cohortes grandes.OBJETIVO:Este estudio tiene como objetivo comparar la resección segmentaria versus la colectomía extendida para el cáncer de colon transverso en términos de resultados oncológicos.DISEÑO:Este fue un estudio de cohorte retrospectivo.ESCENARIO:Este estudio se realizó utilizando una cohorte a nivel nacional.PACIENTES:Un total de 66,062 pacientes que se sometieron a colectomía con intención curativa por adenocarcinoma de colon transverso en estadio I-III fueron identificados en la Base de Datos Nacional del Cáncer (2004-2015).PRINCIPALES MEDIDAS DE RESULTADO:Los pacientes se dividieron en dos grupos según el tipo de cirugía recibida (resección extendida versus resección segmentaria). El resultado primario fue la supervivencia global. Los resultados secundarios fueron la mortalidad a los 30 y 90 días, la duración de la estancia hospitalaria y la tasa de reingreso dentro de los 30 días posteriores al alta quirúrgica.RESULTADOS:Se realizó colectomía extendida en 44,417 (67.2%) casos, mientras que 21,645 (32.8%) pacientes fueron sometidos a resección segmentaria. La colectomía extendida se asoció con una menor supervivencia en el análisis multivariado (HR 1.07 IC 95% 1.04-1.10; p <0.001). El análisis de subgrupos mostró que la resección extendida se asoció de forma independiente con una menor supervivencia en los cánceres de colon transverso medio (HR 1.08 IC 95% 1.04-1.12; p <0.001) y en tumores en estadio III (HR 1.11 IC 95% 1.04-1.18; p <0.001). Un número de al menos 12 ganglios linfáticos cosechados fue un predictor independiente de una mejor supervivencia en los análisis general y de subgrupos.LIMITACIONES:Este estudio estuvo limitado por su diseño retrospectivo.CONCLUSIÓN:La colectomía extendida no se asoció con una ventaja de supervivencia en comparación con la resección segmentaria. Por el contrario, la colectomía extendida se asoció con una supervivencia levemente menor en cánceres de colon transverso medio y tumores localmente avanzados. Se encontró que la resección segmentaria es segura cuando se logran los márgenes apropiados y la cosecha adecuada de ganglios linfáticos. Consulte Video Resumen en http://links.lww.com/DCR/B454.

Anomalous origin of the middle colic artery from the ileocecal artery affecting laparoscopic ascending colon cancer resection

The anomalies of the middle colic artery have rarely been reported and reviewed in literature. However, in case such anomalies are observed in clinical practice, surgery must still be performed safely. This report presents the case of a 78-years-old female who underwent ileocecal resection and hepatectomy due to ascending colon cancer with liver metastasis. Preoperative abdominal contrast-enhanced computed tomography showed an anomaly of the middle colic artery. Since such anomaly is extremely rare, preoperative evaluation of vascular structure is important for safely performing the surgery.

Surgical management of adenocarcinoma of the transverse colon: What should be the extent of resection?

Transverse colon, owing its origin to midgut and hindgut and harbouring a flexure at both ends, continues to pose a surgical challenge. When compared to the rest of the colon, transverse colon adenocarcinoma is relatively uncommon. These cancers usually present late and lie in close proximity to the stomach, omentum, and pancreas. Adequate lymphadenectomy entails dissection around and ligation of the middle colic vessels. Hence, resectional surgery for transverse colon carcinoma is considered difficult. This is more so because of the variation of arterial and venous anatomy. From this perspective, the surgeon is tempted to perform a more radical operation like extended right or left hemicolectomy to secure an adequate lymphadenectomy. Such a cancer has also been dealt with a more limited transverse colectomy with colo-colic anastomosis. For all these reasons, patients with transverse colon adenocarcinoma were excluded from randomised trials which compared laparoscopic resection with traditional open operation. Surgical literature is yet to establish a definite operation for transverse colon cancer and the exact procedure is often dictated by surgeon's preference. This is primarily because this is an uncommon cancer. The rapid adoption of laparoscopic operation favoured extended colectomy as transverse colectomy can be difficult by minimally invasive technique. However, in the recent past, cohort studies and meta-analyses have shown equivalent oncological outcome between transverse colectomy and extended colectomy. It is time to resurrect transverse colectomy and consider it equivalent to its radical counterpart for cancers around the mid-transverse colon.

Comparing the safety, efficacy, and oncological outcomes of laparoscopic and open colectomy in transverse colon cancer: a meta-analysis

INTRODUCTION

In order to compare the safety, efficacy, and oncological outcomes of laparoscopic (LC) and open colectomy (OC) for transverse colon cancer (TCC) patients, the present systematic review of the literature and meta-analysis was designed.

METHODS

This study was conducted following the Cochrane Handbook for Systematic Reviews of Interventions and the PRISMA guidelines. A systematic screening of the electronic databases was performed (Medline, Web of Science and Scopus). The validity of the pooled results was verified through the performance of trial sequential analysis (TSA). The level of evidence was estimated using the GRADE approach.

RESULTS

Overall, 21 studies and 2498 patients were included in our study. Pooled comparisons and TSA analyses reported a superiority of LC over OC in terms of postoperative complications (OR 0.64, p = 0.0003), blood loss (WMD - 86.84, p < 0.00001), time to first flatus (WMD - 0.94, p < 0.00001) and oral diet (WMD - 1.25, p < 0.00001), and LOS (WMD - 2.39, p < 0.00001). Moreover, OC displayed a lower operation duration (p < 0.00001). A higher rate of complete mesocolic excision (p = 0.001) was related to OC. Although inconclusive in TSA, the recurrence rate in LC group was lower. LC and OC were equivalent in terms of postoperative survival outcomes.

CONCLUSIONS

Considering several limitations of the eligible studies and the subsequent low level of evidence, further RCTs of a higher quality and methodological level are required to verify the findings of our meta-analysis.