Is there a disadvantage to radical lymph node dissection in colon cancer?

Prognostic value of lymph node distribution after laparoscopic colectomy with Japanese D3 dissection

PURPOSE

Positive pathologic lymph nodes in colorectal cancer represent an important prognostic indicator. Whether lymph node distribution or the number of metastatic nodes is more strongly associated with survival prediction remains controversial.

METHODS

Among 3449 colorectal cancer surgeries performed at Nagasaki University Hospital and five affiliated institutions from April 2016 to March 2022, we investigated 604 patients who underwent laparoscopic radical resection and were diagnosed with pathological stage III cancer. Patients were divided into two groups according to whether they had central vessel metastasis (LND3 group, n=42) or not (LND1/2 group, n=562). After adjusting for background factors using propensity score matching, the LND3 group included 42 patients and the LND1/2 group included 40 patients. Patient background characteristics and prognosis were compared between these two groups.

RESULTS

Before matching, frequencies of right-side colon cancer (64.3% vs 38.1%, p=0.001), multivisceral resection (11.9% vs 4.4%, p=0.039), clinical N2 status (40.5% vs 22.6%, p=0.032), and pathological N2 (73.8% vs 22.6%, p<0.001) were all greater, and the number of lymph nodes retrieved was higher (24 vs 19, p=0.042) in the LND3 group. After matching, no differences in any clinical factors were evident between groups. Five-year RFS (44.8% vs 77.1%, p=0.004) and OS (43.1% vs 83.2%, p<0.001) were worse in the LND3 group. Adjuvant chemotherapy improved RFS (adjuvant chemotherapy (+) vs adjuvant chemotherapy (-): 62.1% vs 27.7%, p=0.047) in the LND3 group.

CONCLUSION

LND3-positive patients show poorer prognosis than LND1/2 patients and should be treated with an appropriate perioperative treatment strategy.

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.

Effects of Oral Pirfenidone on Colon Anastomosis Healing and Adhesion Formation in Rats

INTRODUCTION

Many experimental studies have examined multiple drugs or treatments to improve the healing of intestinal anastomoses. Synthetic prostacyclin analogs, immunosuppressants, erythropoietin, growth hormone, insulin-like growth factor type 1, synthetic metalloproteinases inhibitors, and hyperbaric oxygen therapy have produced promising results in low-risk models of anastomosis dehiscence. However, in high-risk models, only hyperbaric oxygen therapy has been shown to be useful. Pirfenidone (PFD), a commonly used antifibrosing drug, has not been shown to be effective for this purpose. Our objective was to evaluate the effects of PFD on anastomosis healing and adhesion genesis in a low-risk rat model of dehiscence of colonic anastomosis.

METHODS

An experimental study was conducted on 40 healthy Wistar rats randomly assigned to the control group or PFD experimental group (20 rats in each group). Colon anastomosis was performed 3 cm above the peritoneal reflection using the same technique in all animals. Mechanical resistance was studied by measuring bursting pressure. Adhesions were evaluated macroscopic and histologically using common staining techniques. Animals received the first PFD dose 12 h after surgery at a dose of 500 mg/kg one a day (SID) for 5 consecutive days. On day 6, the animals were reoperated on to measure the bursting pressure in situ and to classify adhesions macroscopically, and the anastomosed colon was resected for histological analysis.

RESULTS

There were no deaths, complications, or anastomosis dehiscence in either group. The mean bursting pressure was 120.8 ± 11 mm Hg and 135.5 ± 12.4 in the control and PFD groups, respectively (p < 0.001). The adhesions were less dense and had less inflammatory cell infiltration in the PFD group (p < 0.02 and 0.002, respectively). Collagen content was slightly higher in the PFD group (p = 0.04).

CONCLUSIONS

Our results revealed favorable effects of PFD in this low-risk colon anastomosis model; for example, the bursting pressure was higher, and the macroscopic adhesions were soft and exhibited less inflammatory infiltration and higher collagen content in the PFD group than in the control group. The results showing that PFD treatment was associated with better healing of minor adhesions seem to be paradoxical because the therapeutic indications for this drug are directed at treating fibrosing diseases.

A Comparison between Different Management Surgical Approaches in the Treatment of Splenic Flexure Colon Cancer

Background There are many surgical approaches which described extent of resection of the colon for adequate surgical management of splenic flexure cancer, but up till now there is no established surgical procedure, this is because the presence of double lymphatic drainage of the mesenteric vessels. Segmental resection of the colon for the management of splenic flexure cancer was a recently accepted surgical procedure.

Objective In the present study, we aimed to compare three surgical management techniques to clarify the best management approach of Egyptian patients with splenic flexure cancer regarding operative, clinical, and oncological outcomes: segmental resection, and extended left or right hemicolectomy,.

Materials and Methods In the present study, we included 90 patients with splenic flexure cancer. Cases were divided into 3 groups. Each group included 30 patients in order to compare three surgical techniques: segmental resection, extended left hemicolectomy, and extended right hemicolectomy.

Results We have found no statistically significant differences between the three included groups regarding operative findings, postoperative complications, local recurrence, distant recurrence, disease progression, recurrence-free survival rate, progression-free survival rate, and overall survival rate. The operative time was longer, and the number of lymph nodes was higher in the extended right hemicolectomy group (p < 0.001).

Conclusion We have shown that segmental resection of the splenic flexure is surgically and clinically suitable for the adequate management of operable cases of carcinoma of the splenic flexure.

Does transverse colon cancer spread to the extramesocolic lymph node stations?

BACKGROUND

Transverse colon cancers show behavioral differences in terms of the involvement of extramesocolic lymph nodes since they are closely related to all three embryological planes. These tumors have also been observed in the gastroepiploic-omental (GEOM) region, outside their usual regional areas. We will evaluate this new metastatic route in our own cases.

METHODS

Thirty-four patients (16 female, 18 male) that presented to our clinic with hepatic flexure, transverse colon, and splenic flexure cancer between October 2011 and May 2017 were included in the study. Type of surgery, histopathology, and factors causing metastasis, morbidity, and mortality were evaluated.

RESULTS

Cancer was located in the transverse colon in 20 patients (58.8%), hepatic flexure in 10 (29.4%), and splenic flexure in four (11.7%). Lymph node positivity in the GEOM region was present in four patients: in the infrapyloric region and pancreatic head, close to the hepatic flexure in three patients; and the midline of GEOM, close to the inferior body of the pancreas in one patient. Perineural invasion (p < .05) and N stage (p < .05) were associated with GEOM region metastasis. Tumor localization and age significantly increased pleural effusion.

CONCLUSIONS

In transverse colon and both flexural tumors, we recommend planning the surgery according to the localization of the tumor and including the GEOM, infrapyloric and infrapancreatic areas. It is possible to discuss whether to perform extended excision for all or only selected patients. The best approach seems to be to evaluate the co-factors to manage these patients.

Introduction of complete mesocolic excision with central vascular ligation as standardized surgical treatment for colon cancer in Greece. Results of a pilot study and bi-institutional cooperation

INTRODUCTION

Complete mesocolic excision (CME) is generally accepted as state of the art in colon cancer surgery. However, the long-term impact of CME has not been systematically examined. Therefore cohort studies might be a possible way to clarify any differences between conventional resections and CME. Following bilateral cooperation between the Department of Surgery/University Hospital of Erlangen and the 1^st Surgical Department of the General Hospital of Nikaia/Piraeus, including teaching activities for introduction of CME, a cohort study was performed, considering surgical quality criteria and clinical outcome.

MATERIAL AND METHODS

All patients with colon carcinomas (CME group, n = 31) referred to the 1^st Surgical Department of General Hospital, Nikaia/Piraeus, Greece for surgery from January 2012 to December 2013 were prospectively analyzed and compared with patients who underwent conventional surgery for colon cancer between January 2008 and December 2011 (non-CME group, n = 35). Patients' follow-up was at least 48 months.

RESULTS

There were significantly better results in terms of lymph node yield (CME group: 29.6 vs. non-CME group: 17.85; p < 0.001) and lymph node ratio (LNR) (CME group: 0.12 vs. non-CME group: 0.24; p < 0.001) and recurrence-free survival in favor of the CME group (CME group: n = 0 vs. non-CME group: n = 5) without any increase in surgical morbidity (CME group: n = 6 vs. non-CME group: n = 11; p = 0.10).

CONCLUSIONS

Complete mesocolic excision appears to offer a superior oncological result without any increase of postoperative morbidity and mortality. Furthermore, CME represents a surgical technique which can be established in a surgical department after previous teaching without increasing the postoperative complication rate.

Treatment of splenic flexure colon cancer: a comparison of three different surgical procedures: Experience of a high volume cancer center

Extended right or left hemicolectomy are the most common surgical treatments for splenic flexure colon cancer. Extended resection (including distal pancreasectomy and/or splenectomy), has been often indicated for the treatment for the splenic flexure cancer, because the lymphatic drainage at this site is poorly defined and assumed as heterogeneous. Between January 2006 and May 2016, 103 patients with splenic flexure colon cancer were enrolled in the study. We evaluated the clinicopathological findings and outcomes of all patients and associated them to the different surgical treatment. Out of 103 selected cases an extended right hemicolectomy was performed in 22 (21.4%) patients, an extended left hemicolectomy in 24 (23.3%) patients, a segmental resection of the splenic flexure in 57 (55.3%) patients; the combined resection of adjacent organs showing tumor adherence was carried out in 11 (10.7%) patients. The tumor infiltrated near organs (T4) in 5 patients. No significant differences in complications were found among the three groups. In all groups no differences were found in the total number of harvested lymphnodes. After a median follow-up of 42 months, 30 recurrences and 19 deaths occurred (12 for tumor progression). There was no difference in overall and progression free survival among the three different surgical treatments. According to our results, the partial resection of splenic flexure was not associated with a worse prognosis and it was leading for a satisfactory oncological outcome. It is our opinion that the extended surgery is seldomly indicated to cure splenic flexure cancer.

Gastrocolic trunk of Henle and its variants: review of the literature and clinical relevance in colectomy for right-sided colon cancer

PURPOSE

Venous vascular anatomy of the right colon presents a high degree of variability. Henle's Gastrocolic Trunk is considered an important anatomical landmark by colorectal surgeons. The classical description concerns a bipod vascular structure or tripod, but several variants are associated to it. The aim of this study is to merge the most updated literature on the anatomy knowledge of the Gastrocolic Trunk by evaluating all possible variants, as well as to underline its surgical importance due to its topographical relationships.

METHODS

Twelve studies describing the anatomy of the gastrocolic trunk were selected, each of them dealing with a more or less extensive series of cases. A distinction was drawn between the gastropancreatic trunk, devoid of the colonic component, and the gastrocolic trunk; and then the frequency of the different resulting variants was reported. The data obtained from cadavers and radiological studies were analyzed separately.

RESULTS

The Gastrocolic Trunk is found in 74% of cadaver studies, and in 86% of radiological studies. Its most frequent configuration is represented by the union of right gastroepiploic vein + anterior superior pancreaticoduodenal vein + superior right colic vein, respectively, 32.5% and 42.5%, followed by the right colic vein which replaces (26.9%, 12.3%) or is added (10%, 20.1%) to the superior right colic vein.

CONCLUSIONS

The superior right colic vein joins the right gastroepiploic vein and the anterior superior pancreaticoduodenal vein thus forming, in most cases, the gastrocolic trunk. The anatomical knowledge of vascular structures forms the basis for both the interpretation of preoperative radiological images and the surgical procedure itself, despite the considerable anatomical variability of tributaries.

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.

Surgical and oncological outcomes after complete mesocolic excision in right-sided colon cancer compared with conventional surgery: a retrospective, single-institution study

PURPOSE

The aim of the study was whether complete mesocolic excision (CME) with central vascular ligation (CVL) is associated with a survival benefit compared with traditional procedure in right-sided colon cancer.

METHODS

Overall, 251 consecutive patients underwent surgery for right colon cancer between 2007 and 2012. After exclusion, 95 subjects received non-CME surgery before 2010, and 97 subjects received CME surgery after January 2010, when we started to perform CME systematically. The number of lymph nodes, morbidity, and mortality was analyzed. Overall survival (OS) and disease-specific survival (DSS) were investigated.

RESULTS

The median number of examined lymph nodes was 33.28 in the CME group and 26.92 in the non-CME group, p < 0.001. Postoperative complications were 21.6% in the CME group and 17.8% in the non-CME group, without significant difference. One out of 192 patients died. Three-year OS was 88% in the CME group and 71% in the non-CME group (p = 0.003). In stage II, 3-year DSS was 97% in the CME group and 86% in the non-CME group. In stage III, the 3-year DSSs in the CME and in the non-CME groups were 86 and 67%, respectively (p < 0.001). Cox's regression showed that CME (p = 0.0012), the number of lymph nodes (p = 0.029), and TNM stage (p < 0.001) were significant independent predictors of DSS at 3 years.

CONCLUSION

Surgical standardization of CME with CVL for right-sided colon cancer is associated with better staging and prognosis, particularly in UICC stage II and III. This study shows that CME is safe and reproducible with acceptable morbidity.

Procedural difficulty differences according to tumor location do not compromise the clinical outcome of laparoscopic complete mesocolic excision for colon cancer: a retrospective analysis

Laparoscopic colectomy procedures and their corresponding difficulty levels may vary depending on the tumor location within the colon, and a laparoscopic complete mesocolic excision (CME) with central vascular ligation (CVL) would require more proficiency than a conventional laparoscopic colectomy. We aimed to report our laparoscopic CME with CVL data and to investigate the clinical outcome differences of laparoscopic CME with CVL by various tumor sub-site locations. Prospectively collected clinical data of consecutive patients who received laparoscopic colectomy for primary colon cancer between April 1995 and December 2010 from single surgeon were retrospectively reviewed. All of the included surgery was performed on the basis of CME with CVL principle with no-touch isolation technique. Data were analyzed and compared among three groups; patients who received right or extended right hemicolectomy (group A, n = 142), transverse colectomy or left or extended left hemicolectomy (group B, n = 59), and sigmoidectomy or anterior resection (group C, n = 210). Female patients were more common in group A (53.5% vs. 37.3% vs. 39.5%, p = 0.020). Other baseline characteristics were comparable. Operative time was shorter in group C than the other groups (309.0 ± 74.7 vs. 324.3 ± 89.1 vs. 280.1 ± 93.1 min, p = 0.000). There was no significant difference among groups in perioperative complication and patient recovery. Five-year overall survival, disease-free survival and local recurrence rate showed no difference for a median follow up period of 73 (1–120) months. In conclusion, laparoscopic tumor-specific CME and CVL for colon cancer can be performed with comparable short- and long-term outcomes regardless of tumor sub-site location except for the operative time.

Laparoscopic complete mesocolic excision with central vascular ligation in 600 right total mesocolectomies: Safety, prognostic factors and oncologic outcome

BACKGROUND

To analyze our experience with laparoscopic right Mesocolectomy in right colonic cancers.

METHODS

600 consecutive patients were studied.

RESULTS

Mortality was 0.5%; morbidity was 35.5%. Mean mesocolic area was 15339 ± 1639 mm3, specimen length 24.3 ± 3.3 cm, distance from the tumor to high tie was 103 ± 6 mm and mean lymph nodes harvested was 27 ± 3; mesocolic plane was achieved in 81% of cases. Survival was 83%; stratified survival in patients with stage II, IIIA/B and in the subgroup of stage IIIC patients with negative apical nodes was 88.7%, 72.4%, 71.4% respectively; stage IIIC patients with positive apical nodes showed poor survival (27.7%). Recurrence occurred in 177 patients (29.5%) and was mainly systemic (22.7%). At the multivariate analysis, "non mesocolic" plane of resection, positive N3 apical nodes and CEA levels >5 ng/dL were found to be independent prognostic factors.

CONCLUSIONS

Laparoscopic right Mesocolectomy showed to be safe and yielded surgical specimens of high quality, with impact on survival; positive N3 apical nodes and "non mesocolic" planes were independently associated to poor outcome.

Long-term results following an anatomically based surgical technique for resection of colon cancer: a comparison with results from complete mesocolic excision

AIM

Complete mesocolic excision (CME) has been advocated as likely to improve the long-term oncological outcome of colon cancer resection, although there is a paucity of long-term results in the literature. The aim of this study was to supplement our previously published results on colon cancer resection based on a standardized technique of precise dissection along anatomical planes with high vascular ligation and to compare our long-term results with those of recent European studies of CME.

METHOD

Data were drawn from a prospective hospital registry of consecutive resections for colon cancer between 1996 and 2007, including follow-up to the end of 2012. The principal outcomes from potentially curative resections were 5-year Kaplan-Meier rates of local recurrence, systemic recurrence, overall survival and cancer-specific survival. Secondary outcomes for all resections were postoperative complications, number of lymph nodes retrieved and R0 status.

RESULTS

For 779 potentially curative resections the local recurrence rate was 2.1% (95% CI 1.3-3.4), the systemic recurrence rate was 10.2% (95% CI 8.1-12.7), the 5-year overall survival rate was 76.2% (95% CI 73.0-79.0) and the cancer-specific survival rate was 89.8% (95% CI 87.3-91.9). For all 905 resections, rates of 14 surgical complications were low and not dissimilar to those in a comparable study. The median lymph node count was 15 (range 0-113). R0 status was confirmed in 883/905 patients (97.6%; 95% CI 96.4-98.5).

CONCLUSION

For colon cancer, meticulous dissection along anatomical planes together with high vascular ligation results in few complications, a high R0 rate, low recurrence and high survival.

Prognostic Impact of Distribution of Lymph Node Metastases in Stage III Colon Cancer

BACKGROUND

Complete mesocolic excision (CME) with central vascular ligation (CVL) is a well-known concept in colon cancer surgery. However, data on the oncological benefits of CVL are scarce. The objective of this study was to evaluate the prognostic significance of the distribution of lymph node metastases (LND) in patients with stage III colon cancer who underwent CME with CVL.

METHODS

In total, 446 consecutive patients who underwent curative resection for stage III colon cancer from 2005 to 2011 were analyzed. Patients were classified as having LND1 (metastases in pericolic nodes), LND2 (metastases in intermediate nodes), or LND3 (metastases in main nodes). Survival outcomes were compared among the three groups.

RESULTS

LND1, LND2, and LND3 were identified in 299 (67.0 %), 122 (27.4 %), and 25 (5.6 %) patients, respectively. The 5-year overall survival and relapse-free survival (RFS) of all patients were 86.7 and 76.2 %, respectively. The 5-year RFS of patients with LND1, LND2, and LND3 were 82.8, 65.4, and 52.0 %, respectively (p < 0.0001). Multivariate analysis showed that LND2 was an independent prognostic factor for RFS (p = 0.0185), although the significance of LND3 was marginal (p = 0.0621). Among patients with pN1, the 5-year RFS of patients with LND1 and LND2+3 were significantly different (84.4 vs. 71.5 %, respectively, p = 0.0102), and similar tendency was found between patients with pN2-LND1 and pN2-LND2+3 (72.6 vs. 53.1 %, p = 0.0428).

CONCLUSION

The high 5-year survival rates of patients with stage III colon cancer, even those with LND2 and LND3, would justify CVL as the standard procedure for advanced colon cancer.

Laparoscopic Surgery for Transverse Colon Cancer: Short- and Long-Term Outcomes in Comparison with Conventional Open Surgery

BACKGROUND

Published studies on laparoscopic surgery for transverse colon cancer are scarce. More studies are necessary to evaluate the feasibility, safety, and long-term oncologic outcomes of laparoscopic surgery for transverse colon cancer.

SUBJECTS AND METHODS

From April 1996 to December 2010, 102 consecutive patients with stage II or III disease who had undergone curative resection for transverse colon cancer were enrolled. Seventy-nine patients underwent laparoscopy-assisted colectomy (LAC), whereas 23 patients underwent conventional open colectomy (OC). Short- and long-term outcomes of the two groups were compared.

RESULTS

The OC group had a larger tumor size (7.6 ± 3.4 cm versus 5.2 ± 2.3 cm, P = .004) and more retrieved lymph nodes (26.4 ± 11.6 versus 17.5 ± 9.4, P = .002), without differences in resection margins. In the LAC group, return to diet was faster (4.5 ± 1.2 days versus 5.4 ± 1.8 days, P = .013), and postoperative hospital stay was shorter (12.1 ± 4.2 days versus 15.9 ± 4.8 days, P = .000). There were no differences in occurrence of intra- or postoperative complications. There were no statistically significant differences in overall survival rate (OS) or disease-free survival rate (DFS) between the two groups (5-year OS, 90.4% versus 90.5%, P = .670; 5-year DFS, 84.2% versus 90.7%, P = .463).

CONCLUSIONS

Laparoscopic surgery for transverse colon cancer has better short-term outcomes compared with open surgery, with acceptable long-term outcomes. As in colorectal cancer of other sites, laparoscopic surgery can be a feasible alternative to conventional surgery for transverse colon cancer.

Outcome for stage II and III rectal and colon cancer equally good after treatment improvement over three decades

PURPOSE

This study aimed to investigate the outcome for stage II and III rectal cancer patients compared to stage II and III colonic cancer patients with regard to 5-year cause-specific survival (CSS), overall survival, and local and combined recurrence rates over time.

METHODS

This prospective cohort study identified 3,355 consecutive patients with adenocarcinoma of the colon or rectum and treated in our colorectal unit between 1981 and 2011, for investigation. The study was restricted to International Union Against Cancer (UICC) stages II and III. Postoperative mortality and histological incomplete resection were excluded, which left 995 patients with colonic cancer and 726 patients with rectal cancer for further analysis.

RESULTS

Five-year CSS rates improved for colonic cancer from 65.0% for patients treated between 1981 and 1986 to 88.1% for patients treated between 2007 and 2011. For rectal cancer patients, the respective 5-year CSS rates improved from 53.4% in the first observation period to 89.8% in the second one. The local recurrence rate for rectal cancer dropped from 34.2% in the years 1981-1986 to 2.1% in the years 2007-2011. In the last decade of observation, prognosis for rectal cancer was equal to that for colon cancer (CSS 88.6 vs. 86.7%, p = 0.409).

CONCLUSION

Survival of patients with colon and rectal cancer has continued to improve over the last three decades. After major changes in treatment strategy including introduction of total mesorectal excision and neoadjuvant (radio)chemotherapy, prognosis for stage II and III rectal cancer is at least as good as for stage II and III colonic cancer.

Comparative effectiveness in colon and rectal cancer

Treatment of colorectal cancer is becoming more uniform, with wider acceptance of standardized guidelines. However, areas of controversy exist where the appropriate treatment is not clear, including: should a segmental colectomy or a more extensive resection be performed in hereditary nonpolyposis colorectal cancer? should an asymptomatic primary cancer be resected in the presence of unresectable metastatic disease? what is the role of extended lymph node resection in colon and rectal cancer? are there clinically significant benefits for a robotic approach to colorectal resection versus a laparoscopic approach? This chapter will examine these issues and discuss how they may be resolved.

Lymph node metastasis of carcinomas of transverse colon including flexures. Consideration of the extramesocolic lymph node stations

PURPOSE

Complete mesocolic excision (CME) is nowadays state of the art in the treatment of colon cancer. In cases of carcinoma of transverse colon and of both flexures an extramesocolic lymph node metastasis can be found in the infrapancreatic lymph node region (ILR) and across the gastroepiploic arcade (GLR). These direct metastatic routes were not previously systematically considered. In order to validate our hypothesis of these direct metastatic pathways and to obtain evidence of our approach of including dissection of these areas as part of CME, we initiated a prospective study evaluating these lymph node regions during surgery.

METHODS

Forty-five consecutive patients with primary tumour manifestation in transverse colon and both flexures between May 2010 and January 2013 were prospectively analyzed. Patients were followed up for at least 6 months. Mode of surgery, histopathology, morbidity and mortality were evaluated.

RESULTS

Twenty-six patients had a carcinoma of transverse colon, 16 patients one of hepatic flexure and four patients one of splenic flexure. The median lymph node yield was 40. Occurrence of lymph node metastasis in ILR was registered in five patients and in GLR in four patients. The mean lymph node ratio was 0.085. Postoperative complications occurred in nine patients, and postoperative mortality was 2 %.

CONCLUSIONS

We were able to demonstrate this novel metastatic route of carcinomas of the transverse colon and of both flexures in ILR and GLR. These could be considered as regional lymph node regions and have to be included into surgery for cancer of the transverse colon including both flexures.

Complete mesocolic resection and extended lymphadenectomy for colon cancer: a systematic review

AIM

Complete mesocolic excision (CME) and extended lympha-denectomy (EL) have been proposed as safe procedures for improving colon cancer survival outcomes. The aim of this study was to evaluate the evidence regarding oncological outcomes, morbidity and mortality after such techniques for colon cancer.

METHOD

A systematic review of the literature was conducted to evaluate evidence regarding oncological outcomes, morbidity and mortality after CME or EL. Three major databases (PubMed, MEDLINE and the Cochrane Library) were searched. The review included original articles reporting outcomes after CME or EL from January 1950 to July 2012.

RESULTS

Twenty-one, predominately retrospective, studies involving 5246 patients (mean age 68.2 years, 56.5% men) were included. Reporting of outcomes was inconsistent. Median follow up was 60 months. The operative mortality rate was 3.2% and the cumulative morbidity rate was 21.5%. The weighted mean local recurrence rate and the 5-year overall and disease-free survival rates were 4.5%, 58.1% and 77.4%, respectively.

CONCLUSION

The available data for CME and EL have numerous fundamental limitations that prohibit adoption. Contemporary controlled studies are required before universal recommendation.

[Laparoscopic surgery for colon cancer: quality requirements for (extended) right hemicolectomy]

The current S3 guidelines on the surgical treatment of colorectal cancer note that with a suitable patient selection and expertise of the surgeon the same oncological results can be achieved laparoscopically as with the open procedure. This requires that the same quality requirements have to be provided for both methods. The most important quality parameters of right sided (extended) hemicolectomy are central ligation of the supplying arteries (ileocolic artery, right branch of the middle colic artery and middle colic artery) flush to the central origin of the vessel (superior mesenteric artery or middle colic artery) and the sharp dissection of the mesocolon without any preparation tears. The photographic documentation of the fresh surgical specimens for categorizing the preparation quality as well as to determine the pedicle of the vessel can capture this quality well and is also currently the best surrogate parameter to evaluate the oncological quality of the operation. At present, there are still considerable widespread deficits not only with the laparoscopic approach but also in open surgery which must be urgently fixed.

Extended lymphadenectomy in colon cancer is crucial

No one doubts that lymph node dissection in colon cancer is necessary, it is just the extent of that dissection that is still under debate. As the individual steps of an oncologic operation cannot be separated from each other, analysis of the significance of lymph node dissection alone is difficult. It has been proven that the T category is directly related to the number and central spread of lymph node metastases. Micrometastases and isolated tumor cells may be detected in lymph nodes by using special staining techniques; their presence may worsen prognosis significantly and approximate it to UICC stage III. The numbers of dissected lymph nodes and the ratio of involved versus dissected lymph nodes have been used as markers for quality of surgery and histopathological evaluation. Recent results underscore the importance of technique and extent of dissection. Dissection must be performed along the embryologic planes of the mesocolon and leave them intact. A high vascular tie with preservation of the central hypogastric nerves must be applied in order to achieve the best oncologic results while preserving quality of life. Extended lymphadenectomy is oncologically relevant only when it is combined with removal of the primary tumor with adequate longitudinal clearance, an intact complete mesocolon, and high vascular tie. It is part of a concept in which the tumor-bearing specimen is harvested as an enveloped package to minimize the risk of tumor cell spillage and local recurrence.

Qualitative and quantitative issues of lymph nodes as prognostic factor in colon cancer

For patients undergoing curative resections for colon cancer, the nodal status represents the strongest prognostic factor, yet at the same time the most disputed issue as well. Consequently, the qualitative and quantitative aspects of lymph node evaluation are thus being scrutinized beyond the blunt distinction between 'node positive' (pN+) and 'node negative' (pN0) disease. Controversy ranges from a minimal or 'least-unit' strategy as exemplified by the 'sentinel node' to a maximally invasive or 'all inclusive' approach by extensive surgery. Ranging between these two extremes of node sampling strategies are factors of quantitative and qualitative value, which may be subject to modification. Qualitative issues may include aspects of lymph node harvest reflected by surgeon, pathologist and even hospital performance, which all may be subject to modification. However, patient's age, gender and genotype may be non-modifiable, yet influence node sample. Quantitative issues may reflect the balance between absolute numbers and models investigating the relationships of positive to negative nodes (lymph node ratio; log odds of positive lymph nodes). This review provides an updated overview of the current controversies and a state-of-the-art perspective on the qualitative and quantitative aspects of using lymph nodes as a prognostic marker in colon cancer.