Surgical techniques for advanced transverse colon cancer using the pincer approach of the transverse mesocolon

Laparoscopic excision of a retroperitoneal pseudocyst using a modified medial approach: A case report

INTRODUCTION

Retroperitoneal pseudocysts of non-pancreatic origin are rare. Although the laparoscopic approach has been used for their treatment, laparotomy remains the mainstream strategy for these lesions.

PRESENTATION OF CASE

We report the case of an asymptomatic 51-year-old male patient who was incidentally diagnosed with a retroperitoneal pseudocyst. Computed tomography showed a 3 × 3 cm cystic lesion in the retroperitoneum, localized between the third part of the duodenum and the inferior vena cava. The patient underwent complete laparoscopic excision using a modified right-sided colonic resection procedure (modified medial approach), and histopathological examination revealed a non-pancreatic retroperitoneal pseudocyst. The patient was discharged without any complications, and no postoperative recurrence was detected.

DISCUSSION

Complete excision is of great significance in the treatment of retroperitoneal cysts. There have been few studies on the laparoscopic approach for retroperitoneal pseudocysts. A laparoscopic procedure is less invasive and helps identify the correct tissue planes to ensure complete resection and prevent inadvertent injury to adjacent vital structures. We detached the retroperitoneal lesion from the duodenum and safely removed it without damaging the surrounding organs by a modified medial approach.

CONCLUSIONS

Retroperitoneal pseudocysts can be resected laparoscopically by identifying the correct tissue planes and adjacent vital structures.

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.

Efficacy and Safety of rCCK96-104PE38 Targeted Drug in the General Surgical Treatment of Colon Cancer

To evaluate the clinical efficacy and safety of the rCCK96-104PE38 targeted drug in patients with colon cancer in general surgery, data of 80 patients with colon cancer who were admitted to the hospital from April 2019 to July 2021 were selected and randomly divided into the treatment group and the control group, with 40 cases in each group. Patients in the treatment group were treated with the rCCK96-104PE38 targeted drug, and those in the control group were treated with oxaliplatin. The treatment efficiency and incidence of adverse reactions were compared between the two groups. The inverse cholecystokinin (CCK96-104) was fused with pseudomonas aeruginosa exotoxin (PE38 toxin) through the gene amplification technique to construct a prokaryotic expression vector. Then, the rCCK96-104PE38 was purified by Ni-nitrilotriacetate (Ni-NTA) affinity chromatography, and the antitumor activity of rCCK96-104PE38 was verified. The results showed that the amplified rCCK96-104PE38 sequence was correct and the pET-28a prokaryotic expression system was adopted to successfully achieve active expression. The purified recombinant protein could induce the apoptosis of colon cancer cells in vitro and inhibit tumor growth in vivo. The total effective rate in the treatment group (80%, 32/40) was higher than that in the control group (60%, 24/40) (P < 0.05). To sum up, the recombinant toxin rCCK96-104PE38 could not only specifically adsorb the colon cancer cells with high expression of CCK2R but also effectively inhibit tumor tissue growth and proliferation. Besides, the rCCK96-104PE38 protein had a good anticancer effect that helped effectively reduce the incidence of adverse reactions in patients, which was worthy of promoting.

Laparoscopic resection surgery for malignant transformation of extragonadal endometriosis by the “pincer” approach

Up to 1% of women with endometriosis develop endometriosis-associated neoplasms [1]. Most endometriosis-associated malignant tumors develop from the ovarian endometriomas, whereas those developing from extragonadal lesions are extremely rare, estimated at 0.2% [2]. Because they are uncommon, a treatment protocol for the malignant transformation of extragonadal endometriosis lesions has not been clearly defined. When the lesion is confined to the site of origin and R0 resection is achieved, the 5-year survival rate is between 82% and 100%; therefore, complete resection should be performed [3]. The patient in this video had previously undergone hysterectomy, bilateral salpingo-oophorectomy, left nephrectomy, and low-anterior resection of the rectum due to severe endometriosis. Ten years after the surgery, the patient had a 6 cm endometrioid adenocarcinoma developing from the residual endometriosis lesion at the left uterosacral ligament that involved the bladder, left ureter, and rectum. In this case, the tumor was attached to the pelvis due to infiltration of the left sacrospinous ligament. To completely remove the tumor, we used laterally extended endopelvic resection with abdominoperineal resection of the rectum. We used the laparoscopic-perineal-laparoscopic approach (pincer approach) because improved visualization of the left sacrospinous ligament increases the probability of achieving complete resection [4]. Pathological R0 resection was achieved without intraoperative or postoperative complications. Thus, for tumors that are firmly attached to the pelvic floor, the pincer approach can be useful for achieving R0 resection. The informed consent for use of this video was taken from the patient.

Analysis of the Positional Relationship Among the Operator, Camera, and Monitor: Overcoming the Difficulties of Mirror-image Conditions During Laparoscopic Surgery

BACKGROUND

Although methods to overcome difficulties associated with mirror-image conditions have been investigated, the ideal spatial relationship among the operator line of sight, monitor location, and camera location remains unclear. Moreover, the best training method for improving laparoscopic surgical skills under varying operator line of sight, camera, and monitor positions is unknown. We aimed to investigate the role of laparoscopic training under mirror-image conditions in improving surgical efficiency and whether prior surgical experience affects such training.

METHODS

This prospective study was conducted at the Department of Surgical Oncology, Tokyo University, Japan. Twenty-five surgeons participated. Novice (n=14), trained (n=7), and expert (n=4) participants performed the simulated task in a box trainer while varying the positional relationships among the surgeons, camera, and monitor. Five patterns were repeatedly performed 5 times per day for 4 days over 2 weeks.

RESULTS

The most significant differences in terms of the time required to complete the task under mirror-image conditions among the 3 groups were on day 1 (novices: 185.8 s, trained: 79.7 s, and experts: 46.5 s, P=0.009). However, after 4 days of training, the corresponding times did not differ among the 3 groups (26.0, 30.7, and 23.1 s, respectively; P=0.415). Laparoscopic training was sufficiently effective under mirror-image conditions.

CONCLUSIONS

Mirror-image surgical conditions provided the most difficult setting, because surgeons and assistants often became disoriented, and task performance was most degraded. However, just 4 days of training was found to be sufficient to overcome the difficulties encountered while performing laparoscopic procedures under mirror-image conditions.

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.

Current status and trend of laparoscopic right hemicolectomy for colon cancer

Laparoscopic right hemicolectomy (LRH) is utilized worldwide as one of the standard surgical treatments for right-sided colon cancer. However, there have been issues concerning its applicability, techniques, and trend. The present study aimed to elucidate the current status and trend of LRH by reviewing literature focusing on important issues associated with this surgery. Based on previous studies, LRH most likely provides better short-term outcomes and similar oncological outcomes compared to open surgery. Despite the increasing use of robotic approach in this surgery, it seems to have always been associated with longer operative times and greater hospital cost with limited advantage. Intracorporeal anastomosis seems to improve short-term outcomes, such as quicker recovery of bowel function, compared to extracorporeal anastomosis. However, it does not contribute to shorter hospital stay. With regard to dissection technique, various approaches, and landmarks have been advocated to overcome the technical difficulty in LRH. This difficulty is likely to be caused by anatomical variation, especially in venous structures. The superiority of one approach or landmark over another is still argued about due to the lack of large-scale prospective studies. However, deep understanding both of anatomical variation and characteristics of each approach would be of extreme importance to minimize adverse effects and maximize patient benefit after LRH.