Unveiling the hidden: identification and management of overlooked blood vessels in laparoscopic left hemicolectomy for splenic flexure cancer

BACKGROUND

During laparoscopic left hemicolectomy procedures, a previously overlooked consistently thick blood vessel within the gastrocolic ligament near the splenic hilum may contribute to post-operative bleeding complications. The purpose of this study was to investigate the identification and management of the previously overlooked blood vessel.

METHODS

This is a retrospective descriptive study of patients undergoing laparoscopic left colectomy for splenic fexure cancer conducted at a national gastrointestinal surgery centre in China. Consecutive patients with splenic fexure cancer who underwent laparoscopic left colectomy using our"five-step process"(n = 34) between January 2021 and July 2023 were included.

RESULTS

The vessels can be effectively exposed using the aforementioned "five-step process." It was observed that the overlooked vessels consistently present in all patients were identified as the omental branch of the left gastroepiploic artery and vein.

CONCLUSION

We have identified the origin of previously overlooked blood vessels and recommended a safe method for their management. This may offer advantages to colorectal surgeons performing laparoscopic left colectomy for splenic flexure cancer.

Splenic flexure cancer: is right extended hemicolectomy better than left hemicolectomy?

INTRODUCTION

There is no consensus on the optimal surgery for splenic flexure cancers.

METHODS

Review of a prospectively maintained database of patients with splenic flexure cancer undergoing either a right extended hemicolectomy or left hemicolectomy at a tertiary care cancer hospital from 14.5.2010 to 16.9.2021. The primary outcome measures were postoperative morbidity and hospital stay with secondary outcomes being overall survival, disease-free survival, and long-term patient reported functional and quality of life outcomes.

RESULTS

The demographic variables were evenly distributed between groups, and median follow-up was 44 months. The groups were comparable in terms of postoperative morbidity (Clavien-Dindo complication ≥ 3a 10.6% vs 10%, p = 0.322) and hospital stay (8 days vs 7 days, p = 0.316). Oncological outcomes were similar in both groups (3-year disease-free survival 71.8% vs 67.8%, p = 0.877, and 3-year overall survival 83.9% vs 75.8%, p = 0.787), and long-term patient-reported functional outcomes were excellent in both groups.

CONCLUSION

Oncological outcomes, post operative morbidity, and long-term patient reported functional outcomes are comparable in patients undergoing either a right extended or left hemicolectomy for splenic flexure cancer.

Minimally invasive vs. open segmental resection of the splenic flexure for cancer: a nationwide study of the Italian Society of Surgical Oncology-Colorectal Cancer Network (SICO-CNN)

BACKGROUND

Evidence on the efficacy of minimally invasive (MI) segmental resection of splenic flexure cancer (SFC) is not available, mostly due to the rarity of this tumor. This study aimed to determine the survival outcomes of MI and open treatment, and to investigate whether MI is noninferior to open procedure regarding short-term outcomes.

METHODS

This nationwide retrospective cohort study included all consecutive SFC segmental resections performed in 30 referral centers between 2006 and 2016. The primary endpoint assessing efficacy was the overall survival (OS). The secondary endpoints included cancer-specific mortality (CSM), recurrence rate (RR), short-term clinical outcomes (a composite of Clavien-Dindo > 2 complications and 30-day mortality), and pathological outcomes (a composite of lymph nodes removed ≧12, and proximal and distal free resection margins length ≧ 5 cm). For these composites, a 6% noninferiority margin was chosen based on clinical relevance estimate.

RESULTS

A total of 606 patients underwent either an open (208, 34.3%) or a MI (398, 65.7%) SFC segmental resection. At univariable analysis, OS and CSM were improved in the MI group (log-rank test p = 0.004 and Gray's tests p = 0.004, respectively), while recurrences were comparable (Gray's tests p = 0.434). Cox multivariable analysis did not support that OS and CSM were better in the MI group (p = 0.109 and p = 0.163, respectively). Successful pathological outcome, observed in 53.2% of open and 58.3% of MI resections, supported noninferiority (difference 5.1%; 1-sided 95%CI - 4.7% to ∞). Successful short-term clinical outcome was documented in 93.3% of Open and 93.0% of MI procedures, and supported noninferiority as well (difference - 0.3%; 1-sided 95%CI - 5.0% to ∞).

CONCLUSIONS

Among patients with SFC, the minimally invasive approach met the criterion for noninferiority for postoperative complications and pathological outcomes, and was found to provide results of OS, CSM, and RR comparable to those of open resection.

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.

Surgical management of splenic flexure colon cancer: a retrospective propensity-matched study comparing open and minimally invasive approaches using the national cancer database

PURPOSE

Minimally invasive resection of colon cancer at the splenic flexure can be technically challenging with concerns for a suboptimal oncologic outcome. We aimed to compare open and minimally invasive approaches following curative resection.

METHODS

The National Cancer Database was queried for patients with non-metastatic colon adenocarcinoma at the splenic flexure who underwent resection from 2010 to 2016. Cohorts were separated into open and minimally invasive approaches, and demographic and clinicopathologic variables were compared. Propensity-score matching (PSM) was utilized to balance potential confounding covariates between cohorts to elucidate the independent association between surgical approach and outcomes. Kaplan-Meier estimation and Cox-proportional hazards regression were used to analyze survival. Secondary outcomes were analyzed by way of logistic regression or Mann-Whitney U test.

RESULTS

After matching, 842 patients were compared between approaches. Patients who underwent minimally invasive surgery had no significant difference in regional nodes ≥ 12 examined, positive margins, negative circumferential margins, unplanned 30-day readmission, or time from surgery to initiation of chemotherapy when compared to patients who underwent open surgery. Minimally invasive surgery was significantly associated with decreased odds of 30-day mortality, 90-day mortality, and decreased mortality hazard for 5-year overall survival compared to open surgery.

CONCLUSION

The optimal approach for surgical management of splenic flexure colon cancer has not been standardized given its rarity and exclusion from randomized controlled trials. Our retrospective review suggests that minimally invasive resection of splenic flexure colon cancers in carefully selected patients is associated with equivalent oncologic outcomes as well as improved short and long-term survival compared to an open approach.

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.

Supplementary information

The online version of this article (10.1007/s00464-020-08242-8) contains supplementary material, which is available to authorized users.

How we do it: totally laparoscopic complete mesocolon excision for splenic flexure cancer

BACKGROUND

Splenic flexure (SF) cancer is not a common condition and its treatment is still under discussion. Although laparoscopic surgery is well accepted for the treatment of colon cancer at any stage, complete mesocolon excision (CME) with selective vascular ligation using the laparoscopic approach for SF cancer remains technically demanding and represents a real challenge for surgeons.

METHODS

We present a single-institution experience of laparoscopic CME for SF cancer. Intra-operative, pathologic, and post-operative data of patients who underwent laparoscopic SF resection were reviewed to assess the technical feasibility and oncologic safety. Technical features, histopathology, morbidity, and mortality were evaluated.

RESULTS

From February 2015 to October 2017, a minimally invasive approach was proposed to 17 patients (M/F 14/3) affected by splenic flexure cancer. In all patients, the procedure was completed by laparoscopy. The anastomosis was completed intra-corporeally in 89% of cases. The distal margin was 3.1 ± 2.6 cm and the proximal margin was 6.5 ± 3.3 cm from the tumor site. The number of mean harvested nodes was 13.9 ± 7. The mean operative time was 215.5 ± 65 min, and blood loss was 80 ± 27. In one case, a laparoscopic partial gastrectomy was associated due to tumor invasion. The mean post-operative stay was 6.7 ± 3.3 days. Readmission was necessary for two patients. No major morbidity was recorded.

CONCLUSIONS

Despite the wide spread and increasing confidence in laparoscopic colectomy, SF resection remains one of the most challenging procedures in colorectal surgery with a complex learning curve. SF resection with CME and CVL is feasible and safe for the treatment of early-stage and locally advanced SF cancer.

Anatomical and embryological perspectives in laparoscopic complete mesocoloic excision of splenic flexure cancers. Surg Endosc. 2018;32:1202-1208. [PMID: 28812159 DOI: 10.1007/s00464-017-5792-6]

BACKGROUND

Laparoscopic complete mesocoloic excision (CME) with central vascular ligation for splenic flexure cancer is technically challenging because of its anatomical complexity. Although embryological and anatomical consideration should be helpful to perform CME in colorectal cancer surgery, such studies on the splenic flexure are lacking.

METHODS

The splenic flexure is located embryologically between the terminal portion of the midgut and the beginning of the hindgut, and is supplied by the superior mesenteric and inferior mesenteric arteries. The mesentery of the transverse and descending colon originally is a continuous sheet, although they rotate and partially fuse to each other during development. Our surgical strategy was excision of the transverse and descending mesocolon with ligation of the left colic artery and left branch of the middle colic artery, and extraction of the specimen in an intact package wrapped by the embryological planes.

RESULTS

We performed laparoscopic surgery according to our surgical strategy in 17 patients with splenic flexure colon cancer. There were no conversions to open surgery or serious intraoperative complications. Two patients had pathological stage (pStage) I, 5 pStage II, 9 pStage III, and 1 pStage IV disease. No patient had recurrence except for 1 with pStage IV cancer, with a median follow-up of 16 months.

CONCLUSIONS

Our laparoscopic CME technique is feasible for treatment of splenic flexure cancer. Knowledge of anatomy based on embryology is essential to perform this surgery.