Practice parameters for the management of colon cancer

Colorectal cancer: Recent advances in management and treatment

Colorectal cancer (CRC) is the third most common cancer worldwide, and the second most common cause of cancer-related death. In 2020, the estimated number of deaths due to CRC was approximately 930000, accounting for 10% of all cancer deaths worldwide. Accordingly, there is a vast amount of ongoing research aiming to find new and improved treatment modalities for CRC that can potentially increase survival and decrease overall morbidity and mortality. Current management strategies for CRC include surgical procedures for resectable cases, and radiotherapy, chemotherapy, and immunotherapy, in addition to their combination, for non-resectable tumors. Despite these options, CRC remains incurable in 50% of cases. Nonetheless, significant improvements in research techniques have allowed for treatment approaches for CRC to be frequently updated, leading to the availability of new drugs and therapeutic strategies. This review summarizes the most recent therapeutic approaches for CRC, with special emphasis on new strategies that are currently being studied and have great potential to improve the prognosis and lifespan of patients with CRC.

Sigmoid colon cancer presenting as a large abdominal mass accompanied by abscess and rupture: a case report and literature review

Introduction and Importance

Colon cancer presenting as a large abdominal mass accompanied by abscess and rupture is rare and prone to be misdiagnosed and delayed. In addition, the treatment plan is not clear when combined with abdominal wall metastasis.

Case Presentation

A 79-year-old woman presented with a large abdominal mass accompanied by abscess and rupture. It was misdiagnosed as a soft tissue infection in a local hospital, and after a comprehensive examination, it was diagnosed as sigmoid colon cancer with abdominal wall metastasis and abscess formation. The patient underwent a one-stage surgery, including en bloc resection of the tumor and invaded abdominal wall, as well as autologous tissue abdominal wall reconstruction, with a good clinical prognosis.

Clinical Discussion

For the diagnosis of large abdominal masses, abdominal CT, and pus culture are more valuable than ultrasound. For colon cancer with abdominal wall metastasis, one-stage surgery to completely remove the tumor and full-thickness of the abdominal wall, and the use of autologous tissue abdominal wall reconstruction technology to repair defects is feasible.

Conclusion

This case highlights the importance of using colon cancer as one of the differential diagnoses for the diagnosis for large abdominal mass accompanied by abscess and rupture in elderly patients, as well as the possibility of one-stage surgical resection of the tumor and invasion of the abdominal wall and reconstruction of the abdominal wall with autologous tissue when there is abdominal wall metastasis.

Robotic versus laparoscopic right colectomy for nonmetastatic pT4 colon cancer: A European multicentre propensity score-matched analysis

AIM

Minimally invasive surgery has been increasingly adopted for locally advanced colon cancer. However, evidence comparing robotic (RRC) versus laparoscopic right colectomy (LRC) for nonmetastatic pT4 cancers is lacking.

METHODS

This was a multicentre propensity score-matched (PSM) study of a cohort of consecutive patients with pT4 right colon cancer treated with RRC or LRC. The two surgical approaches were compared in terms of R0, number of lymph nodes harvested, intra- and postoperative complication rates, overall (OS), and disease-free survival (DFS).

RESULTS

Among a total of 200 patients, 39 RRC were compared with 78 PS-matched LRC patients. The R0 rate was similar between RRC and LRC (92.3% vs. 96.2%, respectively; p = 0.399), as was the odds of retrieving 12 or more lymph nodes (97.4% vs. 96.2%; p = 1). No significant difference was noted for the mean operating time (192.9 min vs. 198.3 min; p = 0.750). However, RRC was associated with fewer conversions to laparotomy (5.1% vs. 20.5%; p = 0.032), less blood loss (36.9 vs. 95.2 mL; p < 0.0001), fewer postoperative complications (17.9% vs. 41%; p = 0.013), a shorter time to flatus (2 vs. 2.8 days; p = 0.009), and a shorter hospital stay (6.4 vs. 9.5 days; p < 0.0001) compared with LRC. These results were confirmed even when converted procedures were excluded from the analysis. The 1-, 3- and 5-year OS (p = 0.757) and DFS (p = 0.321) did not significantly differ between RRC and LRC.

CONCLUSION

Adequate oncological outcomes are observed for RRC and LRC performed for pT4 right colon cancer. However, RRC is associated with lower conversion rates and improved short-term postoperative outcomes.

Lymph node yield: Impact on oncologic outcomes in oral cavity cancer

BACKGROUND

Lymph node metastases are associated with poor prognosis in oral cavity squamous cell carcinoma (OCSCC). In other cancers, clinical guidelines on the number of lymph nodes removed during primary surgery, lymph node yield (LNY), exist. Here, we evaluated the prognostic capacity of LNY on regional failure, locoregional recurrence, and disease-free survival (DFS) in patients with OCSCC treated by primary neck surgery.

METHODS

This retrospective cohort study took place at Sunnybrook Health Sciences Centre in Toronto, Canada and involved a chart review of all adult patients with treatment-naive OCSCC undergoing primary neck dissection. For each outcome, we first used the maximally selected rank statistics and an optimism-corrected concordance to identify an optimal threshold of LNY. We then used a multivariable Cox proportional hazards model to assess the association between high LNY (>threshold) and each outcome.

RESULTS

Among the 579 patients with OCSCC receiving primary neck dissection, 61.7% (n = 357) were male with a mean age of 62.9 years (standard deviation: 13.1) at cancer diagnosis. When adjusting for sociodemographic and clinical factors, LNY >15 was significantly associated with improved DFS (adjusted HR [aHR]: 0.73, 95% CI: 0.54-0.98), locoregional recurrence (aHR: 0.68, 95% CI: 0.49-0.95), and regional failure (aHR: 0.61, 95% CI: 0.39-0.93).

CONCLUSIONS

Our study findings suggested high LNY to be a strong independent predictor of various patient-level quality of surgical care metrics. The optimal LNY we found (15) was lower than the conventionally recommended (18), which calls for further research to establish validity in practice.

High Ligation of the Inferior Mesenteric Artery in Left-Sided Colon and Rectal Cancer Resection: Rates of Success and Outcomes

BACKGROUND

High ligation of the inferior mesenteric artery, defined as ligation before the takeoff of the left colic artery, is often described as the gold standard in low left-sided colon and rectal cancer surgery. The aim of this study is to quantify the rate of ligation at the described level at a single academic center. Additionally, we examined the relationship between level of ligation and cancer-related outcomes.

METHODS

This retrospective cohort study included patients ages 18 and over with low left-sided colon, rectal, and anal cancers undergoing surgical resection. Radiographic evidence of high ligation was defined as ligation of the inferior mesenteric artery before the takeoff of the left colic artery. Patients with and without radiographic evidence of high ligation on CT were compared. Secondary outcomes include lymph node yield and positivity, need for adjuvant therapy, and time from surgery to adjuvant therapy.

RESULTS

169 patients (54% male) were included in the study. 61.5% of operative reports described high ligation of the IMA. There was radiographic evidence of high ligation in 55.6% of total patients and in 70.2% of patients where high ligation was intended. There was no significant difference in surgeon experience, surgical procedure, or surgical approach. There was no difference in lymph node yield, time to adjuvant chemotherapy, or recurrence rates.

CONCLUSION

This study demonstrates good technical success rate of high ligation of the inferior mesenteric artery but shows no difference in short-term patient-measured outcomes between high and low ligation (or successful and unsuccessful high ligation).

Colorectal cancer treatment guidelines and shared decision making quality and reporting assessment: Systematic review

INTRODUCTION

Physicians must share decisions and choose personalised treatments regarding patients´ beliefs and values.

OBJECTIVE

To analyse the quality of the recommendations about shared decision making (SDM) in colorectal (CRC) and anal cancer treatment clinical practice guidelines (CPGs) and consensus statements (CSs).

METHODS

Guidelines were systematically reviewed following prospective registration (Prospero: CRD42021286146) without language restrictions searching 15 databases and 59 professional society websites from January 2010 to November 2021. A validated 31-item SDM quality assessment tool was employed to extract data in duplicate.

RESULTS

We identified 134 guidelines. Only 46/134 (34.3 %) mentioned SDM. Fifteen (11.1 %) made clear, precise and actionable recommendations, while 9/134 (6.7 %) indicated the strength of the SDM-related recommendations. CPGs underpinned by systematic reviews reported SDM more often than those based on consensus or reviews (35.9 % vs 32.0 %; p = 0.031). Guidelines that reported following quality tools (i.e., AGREE II) more commonly commented about SDM than when it was not reported (75.0 % vs 32.0 %; p = 0.003).

CONCLUSION AND PRACTICE IMPLICATIONS

Most of the CRC and anal treatment guidelines did not mention SDM and it was superficial. Guidelines based on systematic reviews and those using quality tools demonstrated better reporting of SDM. Recommendations about SDM in these guidelines merit urgent improvement.

Case Report: Long-term survival of a patient with advanced rectal cancer and multiple pelvic recurrences after seven surgeries

Background

Rectal cancer has a high risk of recurrence and metastasis, with median survival ranging from 24 months to 36 months. K-RAS mutation is a predictor of poor prognosis in rectal cancer. Advanced rectal cancer can be stopped in its tracks by pelvic exenteration.

Case summary

A 51-year-old woman was diagnosed with advanced rectal cancer (pT4bN2aM1b, stage IV) with the KRAS G12D mutation due to a change in bowel habits. The patient had experienced repeated recurrences of rectal cancer after initial radical resection, and the tumor had invaded the ovaries, sacrum, bladder, vagina and anus. Since the onset of the disease, the patient had undergone a total of seven surgeries and long-term FOLFIRI- or XELOX-based chemotherapy regimens, with the targeted agents bevacizumab and regorafenib. Fortunately, the patient was able to achieve intraoperative R0 resection in almost all surgical procedures and achieve tumor-free survival after pelvic exenteration. The patient has been alive for 86 months since her diagnosis.

Conclusions

Patients with advanced rectal cancer can achieve long-term survival through active multidisciplinary management and R0 surgery.

Association between Enhanced Recovery After Surgery (ERAS) protocol, risk factors and 3-year survival after colorectal surgery for cancer in the elderly

INTRODUCTION

As life expectancy is currently growing, more elderly and fragile patients need colorectal resection for cancer. We sought to assess the link between enhanced rehabilitation after surgery (ERAS), risk factors and overall survival at 3 years, in patients aged 65 and over.

METHODS

Between 2005 and 2017, all patients undergoing colorectal resection for cancer were included. Overall survival at 3 years was compared for patients treated in following ERAS guidelines compared to conventional treatment (pre-ERAS).

RESULTS

661 patients were included (ERAS, n = 325; pre-ERAS, n = 336). The 3-year overall survival rate was significantly better regardless of age for ERAS vs pre-ERAS patients (73.1% vs 64.4%; p = 0.016). With overall survival rates of 83.2% vs 73.8%, 65.4% vs 62.8% and 59.6% vs 40% for the age bands 65-74, 75-84 and ≥ 85 years. The analysis of survival at 3 years by a multivariate Cox model identified ERAS as a protective factor with a reduction in the risk of death of 30% (HR = 0.70 [0.50-0.94], p = 0017) independently of other identified risk factors: age bands, ASA score > 2, smoking, atrial fibrillation and abdominal surgery. This result is confirmed by an analysis of the propensity score (HR = 0.67 [0.47-0.97], p = 0.032).

CONCLUSIONS

Our study shows that ERAS is associated with better 3-year survival in patients undergoing colorectal resection for cancer, independent of risk factors. The practice of ERAS is effective and should be offered to patients aged 65 and over.

Effect of placing double-lumen irrigation-suction tube on closure of anastomotic defect following rectal cancer surgery

PURPOSE

This study aimed to investigate the effect of placement of double-lumen irrigation-suction tubes (DLIST) on the closure of anastomotic defect (AD) after rectal cancer surgery.

METHODS

The study was carried out at two centers managed by one surgeon, both adopted the same treatments. Patients with postoperative AD after rectal cancer surgery from January 2011 to June 2020 were eligible and were divided into a passive drainage (PD) group and a DLIST group according to whether the PD, placed in the rectal cancer surgery, had been replaced with the DLIST. The effect of DLIST on the AL was evaluated.

RESULT

There distributed 76 patients in the DLIST group and 52 in the PD group. A higher closure rate was reported in the DLIST group (46 patients in DLIST group, for a closure rate of 60.5%, and 21 patients in PD group, for a closure rate of 40.4%. HR = 3.05; 95% CI: 1.79-5.19; P < 0.001). Both length of stay and costs of the treatment in the DLIST group were lower (54 days [interquartile range, IQR: 41-17] days vs. 112 days [IQR: 66-27] days, P = 0.005; and $18,721 [IQR: $14,982-4,960] vs. $40,840 [IQR: $20,932-50,529], P < 0.001).

CONCLUSION

Placement of DLIST might serve as an effective method for treating AD following rectal cancer surgery. In comparison with PD, it costs lower to apply DLIST in the treatment of AD and the length of stay is shorter.

Effect of implementation of enhanced recovery after surgery (ERAS) protocol and risk factors on 3-year survival after colorectal surgery for cancer-a retrospective cohort of 1001 patients

PURPOSE

Several recent studies have shown that the enhanced recovery after surgery (ERAS) protocol reduces morbidity and mortality and shortens the length of stay compared to conventional recovery strategy (pre-ERAS). The aim of this study was to evaluate the effect of the implementation of this protocol on 3-year overall survival and postoperative outcome in patients undergoing colorectal resection for cancer.

METHODS

This was a retrospective, single-center, comparative, and non-randomized study. Between January, 2005, and December, 2017, 1001 patients were included (ERAS, n = 497; pre-ERAS, n = 504).

RESULTS

The 3-year overall survival rate was significantly better for ERAS than for pre-ERAS patients (76.1 vs 69.2%; p = 0.017). The length of hospital stay (median 10 days vs 15; p =  ≤ 0.001) and the 90-day readmission rate (15 vs 20%; p = 0.037) were significantly lower in the ERAS group. Three-year recurrence-free survival (p = 0.398) and 90-day complications (p = 0.560) were similar in the two groups. Analysis of 3-year survival by a multivariate Cox model identified ERAS as a protective factor with a 30% reduction in the risk of death: (HR = 0.70 [0.55-0.90]).

CONCLUSION

The implementation of the ERAS protocol was associated with an improvement in 3-year survival, a reduction of the length of hospital stay and the rate of readmission. ERAS is associated with better 3-year survival, independent of other commonly considered parameters. An ASA score > 2, smoking, a history of cancer, and atrial fibrillation are deleterious risk factors linked to earlier mortality.

Laparoscopic versus open colectomy for locally advanced T4 colonic cancer: meta-analysis of clinical and oncological outcomes

BACKGROUND

The aim of this study was to review the early postoperative and oncological outcomes after laparoscopic colectomy for T4 cancer compared with open surgery.

METHOD

MEDLINE, Embase, and the Cochrane Central Register of Controlled Trials were searched for any relevant clinical study comparing laparoscopic and open colectomy as treatment for T4 colonic cancer. The risk ratio (RR) with 95 per cent c.i. was calculated for dichotomous variables, and the mean difference (m.d.) with 95 per cent confidence interval for continuous variables. Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology was implemented for assessing quality of evidence (QoE).

RESULTS

Twenty-four observational studies (21 retrospective and 3 prospective cohort studies) were included, analysing a total of 18 123 patients: 9024 received laparoscopic colectomy and 9099 underwent open surgery. Laparoscopic colectomy was associated with lower rates of mortality (RR 0.48, 95 per cent c.i. 0.41 to 0.56; P < 0.001; I2 = 0 per cent, fixed-effect model; QoE moderate) and complications (RR 0.61, 0.49 to 0.76; P < 0.001; I2 = 20 per cent, random-effects model; QoE very low) compared with an open procedure. No differences in R0 resection rate (RR 1.01, 1.00 to 1.03; P = 0.12; I2 = 37 per cent, random-effects model; QoE very low) and recurrence rate (RR 0.98, 0.84 to 1.14; P = 0.81; I2 = 0 per cent, fixed-effect model; QoE very low) were found.

CONCLUSION

Laparoscopic colectomy for T4 colonic cancer is safe, and is associated with better clinical outcomes than open surgery and similar oncological outcomes.

The Impact of Frailty on Patients Undergoing Liver Resection for Colorectal Liver Metastasis

BACKGROUND

The aim of this study is to assess the impact of frailty on short-term outcomes after hepatectomy for colorectal liver metastasis (CRLM).

METHODS

Patients were identified using the National Surgical Quality Improvement Program (NSQIP). Patients were divided into 3 categories using the 5-item Modified Frailty Index (mFI).

RESULTS

There were 5230 patients included. 52%, 35%, and 13% had mFI scores of 0, 1, and ≥ 2 respectively. Patients with a ≥ 2 mFI score were more likely to experience minor complication (OR 1.34, 95% CI 1.06-1.69), major complication (OR 1.56, 95% CI 1.15-2.12), readmission (OR 1.55, 95% CI 1.12-2.14), unfavorable discharge (OR 2.48, 95% CI 1.62-3.80), 30-day mortality (OR 3.02, 95% CI 1.02-8.95), prolonged length of stay (OR 1.47, 95% CI 1.18-1.83), and bile leak (OR 1.51, 95% CI 1.02-2.24).

CONCLUSION

Frailty is associated with increased post-operative complications. The 5-item mFI can guide risk stratification, optimization, and counseling.

Postoperative Quality Assessment Score Can Select Patients with High Risk for Locoregional Recurrence in Colon Cancer

BACKGROUND

Monitoring surgical quality has been shown to reduce locoregional recurrence (LRR). We previously showed that the arterial stump length (ASL) after complete mesocolic excision (CME) is a reproducible quality instrument and correlates with the lymph-node (LN) yield. We hypothesized that generating an LRR prediction score by integrating the ASL would predict the risk of LRR after suboptimal surgery.

METHODS

502 patients with curative resections for stage I-III colon cancer were divided in two groups (CME vs. non-CME) and compared in terms of surgical data, ASL-derived parameters, pathological parameters, LRR and LRR-free survival. A prediction score was generated to stratify patients at high risk for LRR.

RESULTS

The ASL showed significantly higher values (50.77 mm ± 28.5 mm) with LRR vs. (45.59 mm ± 28.1 mm) without LRR (p < 0.001). Kaplan-Meier survival analysis showed a significant increase in LRR-free survival at 5.58 years when CME was performed (Group A: 81%), in contrast to non-CME surgery (Group B: 67.2%).

CONCLUSIONS

The prediction score placed 76.6% of patients with LRR in the high-risk category, with a strong predictive value. Patients with long vascular stumps and positive nodes could benefit from second surgery to complete the mesocolic excision.

Is neoadjuvant therapy an alternative strategy to immediate surgery in locally perforated colon cancer?

BACKGROUND

Perforations are a rare but serious complication of colorectal cancer. The current standard of treatment is emergent surgery followed by adjuvant chemotherapy. The concern with this approach is not only the uncertainty of achieving a R0 resection but also potential injury to adjacent vessels, nerves and ureters due to inflamed tissue planes. A subset of this patient population with a contained perforation who are clinically stable may have superior oncological outcomes with local sepsis control, neoadjuvant therapy followed by radical resection. The aim of this study is to report on the pre-operative safety profile for neoadjuvant therapy in the setting of an abscess from colon cancer perforation and the short-term oncological surgical quality outcomes.

METHODS

In this retrospective observational study, all consecutive perforated colon cancer receiving neoadjuvant therapy from Jan 2010 to Dec 2019 were included.

RESULTS

There were 21 patients that met the inclusion criteria. The most common symptom at presentation was abdominal pain (71.4%) and most common site of perforation was sigmoid colon (61.9%). Local sepsis control was achieved with a combination of radiological or surgical drainage, diverting ostomy and/or intravenous antibiotics. Thirteen patients had long-course chemoradiation and eight patients had neoadjuvant chemotherapy. Of these, 13 (61.9%) had tumour regression, with one patient having a pathological complete response. All patients achieved a R0 resection.

CONCLUSIONS

In a small subset of patients with colon cancer perforation, this study has demonstrated the potential safe usage of neoadjuvant therapy first before radical surgery to achieve a clear resection margin.

Evaluating the Regional Uptake of Minimally Invasive Colorectal Surgery: a Report from the Surgical Care Outcomes Assessment Program

BACKGROUND

Minimally invasive surgery (MIS) for colorectal disease has well-known benefits, but many patients undergo open operations. When choosing an MIS approach, robotic technology may have benefits over traditional laparoscopy and is increasingly used. However, the broad adoption of MIS, and specifically robotics, across colorectal operations has not been well described. Our primary hypothesis is that rates of MIS in colorectal surgery are increasing, with different contributions of robotics to abdominal and pelvic colorectal operations.

METHODS

Rates of MIS colorectal operations are described using a prospective cohort of elective colorectal operations at hospitals in the Surgical Care Outcomes Assessment Program (SCOAP) from 2011 to 2018. The main outcome was proportion of cases approached using open, laparoscopic, and robotic surgery. Factors associated with increased use of MIS approaches were described.

RESULTS

Across 21,423 elective colorectal operations, rates for MIS (laparoscopic or robotic surgery) increased from 44% in 2011 to 75% in 2018 (p < 0.001). Approaches for abdominal operations (n = 12,493) changed from 2 to 11% robotic, 43 to 63% laparoscopic, and 56 to 26% open (p < 0.001). Approaches for pelvic operations (n = 8930) changed from 3 to 33% robotic, 40 to 42% laparoscopic, and 57 to 24% open(p < 0.001). These trends were similar for high-(100 + operations/year) and low-volume hospitals and surgeons.

CONCLUSIONS

At SCOAP hospitals, the majority of elective colorectal operations is now performed minimally invasively. The increase in the MIS approach is primarily driven by laparoscopy in abdominal procedures and robotics in pelvic procedures.

Treatment of Patients With Late-Stage Colorectal Cancer: ASCO Resource-Stratified Guideline

PURPOSE

To provide expert guidance to clinicians and policymakers in resource-constrained settings on the management of patients with late-stage colorectal cancer.

METHODS

ASCO convened a multidisciplinary, multinational Expert Panel that reviewed existing guidelines, conducted a modified ADAPTE process, and used a formal consensus process with additional experts for two rounds of formal ratings.

RESULTS

Existing sets of guidelines from four guideline developers were identified and reviewed; adapted recommendations from five guidelines form the evidence base and provided evidence to inform the formal consensus process, which resulted in agreement of ≥ 75% on all recommendations.

RECOMMENDATIONS

Common elements of symptom management include addressing clinically acute situations. Diagnosis should involve the primary tumor and, in some cases, endoscopy, and staging should involve digital rectal exam and/or imaging, depending on resources available. Most patients receive treatment with chemotherapy, where chemotherapy is available. If, after a period of chemotherapy, patients become candidates for surgical resection with curative intent of both primary tumor and liver or lung metastatic lesions on the basis of evaluation in multidisciplinary tumor boards, the guidelines recommend patients undergo surgery in centers of expertise if possible. On-treatment surveillance includes a combination of taking medical history, performing physical examinations, blood work, and imaging; specifics, including frequency, depend on resource-based setting.

Additional information is available at www.asco.org/resource-stratified-guidelines.

Synovial sarcoma of the transverse colon metastatic to the chest wall after 3 years of follow-up

We report a fifth case of a transverse colon primary synovial sarcoma. A 31-year-old man with history of grade I obesity presented to an outpatient clinic reporting 6 months of intermittent colicky abdominal pain associated with haematochezia and rectal bleeding. Colonoscopy reported a partially obstructive intraluminal tumour lesion located in the transverse colon. There was no evidence of metastatic disease in the extension studies, so the patient was admitted to the hospital for a laparoscopic subtotal colectomy. Histopathology demonstrated intermediate-grade synovial sarcoma. At the third year of follow-up, the patient presented metastases on the chest wall, which required extensive resection and complementary oncological management.

Prognostic significance of lymph node count in high-risk node-negative colon carcinoma

BACKGROUND

the prognostic value of the number of lymph nodes isolated (< 12 versus ≥ 12) in the surgical specimen continues to be controversial. In this study, the impact of isolating fewer or more than 12 lymph nodes in stage II colon cancer with a high-risk biologic phenotype was analyzed, such as the presence of perineural invasion.

METHODS

all cases of stage II disease (T3-4N0M0) with perineural invasion (PNI+) were retrospectively identified from a prospective database of patients undergoing surgery for colon cancer. The cohort was divided into two groups depending on the number of lymph nodes isolated (< 12 vs ≥ 12). Apart from clinical and surgical data, the patterns of recurrence, overall (OS) and disease-free survival (DFS) at five and ten years were analyzed.

RESULTS

sixty patients met the inclusion criteria, 31.7 % had < 12 lymph nodes isolated and 68.3 % had more than 12 isolated. There were no clinical or surgical differences between the two groups. OS at five and ten years was significantly lower in the patients with < 12 lymph nodes isolated (84.2 %, 62.7 % vs 94.6 % and 91.6 %, p = 0.01). DFS at five and ten years was 51 % vs 86.5 %, respectively (p = 0.005).

CONCLUSION

the number of lymph nodes isolated (with a cutoff of 12) in stage II colon cancer with PNI+ has prognostic value and should therefore be borne in mind when planning adjuvant chemotherapy.

Neoadjuvant chemoradiotherapy in patients with unresectable locally advanced sigmoid colon cancer: clinical feasibility and outcome

Background

Patients with locally advanced sigmoid colon cancer (LASCC) have limited treatment options and a dismal prognosis with poor quality of life. This retrospective study aimed to further evaluate the feasibility and efficacy of neoadjuvant chemoradiotherapy (NACRT) followed by surgery as treatment for select patients with unresectable LASCC.

Methods

We studied patients with unresectable LASCC who received NACRT between November 2010 and April 2019. The NACRT regimen consisted of intensity modulated radiotherapy (IMRT) of 50 Gy to the gross tumor and positive lymphoma node and 45 Gy to the clinical target volume. Capecitabine‑based chemotherapy was administered every 2 (mFOLFOX6) or 3 weeks (CAPEOX). Surgery was scheduled 6–8 weeks after radiotherapy.

Results

Seventy‑two patients were enrolled in this study. Patients had a regular follow-up (median, 41.1 months; range, 8.3–116.5 months). Seventy‑one patients completed NACRT, and sixty-five completed surgery. Resection with microscopically negative margins (R0 resection) was achieved in 64 patients (88.9%). Pathologic complete response was observed in 15 patients (23.1%), and multivisceral resection was necessary in 38 patients (58.3%). The cumulative probability of 3-year overall survival (OS) and progression-free survival (PFS) were 75.8 and 70.7%, respectively.

Conclusions

For patients with unresectable LASCC, neoadjuvant chemoradiotherapy is feasible, surgery can be performed safely and may result in increased survival and organ preservation rates.

Incidence of and Risk Factors for Gastroepiploic Lymph Node Involvement in Patients with Cancer of the Transverse Colon Including the Hepatic Flexure

BACKGROUND

To define the incidence of gastroepiploic lymph node (GLN) metastasis in patients with cancer of the transverse colon, including the hepatic flexure, and to identify the preoperative predictors of GLN involvement in a large-volume center in China.

METHODS

This retrospective monocentric cross-sectional study respected the STROBE statement. Of 3208 consecutive patients who underwent colon cancer resection, a total of 371 patients with cancer of the transverse colon including the hepatic flexure who underwent complete mesocolic excision and GLN resection in our center were retrospectively reviewed between November 2010 and November 2017. Logistic regression was performed to identify predictors of GLN metastasis. Endoscopic obstruction was defined as a luminal obstruction of the colon severe enough to prevent the colonoscope from passing beyond the tumor regardless of the presenting symptoms.

RESULTS

The GLN involvement rate was 4.0 (2.0-6.1)%. Patients who had GLN involvement had a significantly higher rate of endoscopic obstruction (P = 0.030), higher rate of signet ring adenocarcinoma or lymphovascular invasion (P < 0.05), higher preoperative CEA level (P = 0.037), more advanced pN stage (P < 0.001) and more advanced M stage (P = 0.003) than the patients without GLN involvement. ROC curve analyses showed that the cutoff value for CEA was 17.0 ng/ml (46.7% sensitivity, 84.3% specificity, P = 0.037) for the prediction of GLN metastasis. Multivariate analysis showed that endoscopic obstruction, signet ring adenocarcinoma, a CEA level ≥17 ng/ml and M1 stage were independently correlated with the GLN metastasis.

CONCLUSION

The incidence rate of GLN metastasis was low. To the best of our knowledge, the present study was the first to evaluate the preoperative predictors of GLN metastasis. Combinations of predictive factors may be useful for stratifying patients at high risk of GLN metastasis.

Predictive Risk Factors for Postoperative Complications and Its Impact on Survival in Laparoscopic Resection for Colon Cancer

BACKGROUND

Laparoscopic resection is the ideal treatment of colon cancer. The aim of the study was to analyze the predictive factors for postoperative complications and their impact on oncologic outcomes in laparoscopic resections in colon cancer.

MATERIALS AND METHODS

In all patients undergoing elective laparoscopic surgery the number and degree of severity of postoperative complications were recorded and classified according to Clavien-Dindo. A univariate analysis was made of the demographic, surgical, and oncologic variables of patients with and without complications. The statistically significant variables were then entered into a multivariate model. In both groups overall and disease-free survival were analyzed using Kaplan-Meier estimates.

RESULTS

Of 524 patients, 138 (26.3%) experienced some type of complication, 110 less severe (79.7%) and 28 (20.4%) severe. Twenty-nine conversions to open surgery occurred (5.5%) and hospital mortality was 0.2%.In the multivariate analysis, use of corticosteroids [odds ratio (OR): 3.619], oral anticoagulants (OR: 3.49), blood transfusions (OR: 4.30), and conversion to open surgery (OR: 3.93) were significantly associated with the development of complications. However, sigmoid resections were associated with fewer complications (OR: 0.45).Overall 5-year and 10-year survival in both groups, was 83.3%, 74.1%, 76.0%, and 67.1%, respectively (P=0.18). Disease-free survival at 5 and 10 years, excluding stage IV tumors, was 88.6% and 90.4%, respectively (P=0.881).

CONCLUSIONS

The use of corticosteroids, oral anticoagulants, blood transfusions, and conversion to open surgery are all independent predictive factors of postoperative complications. Sigmoid resections are associated with fewer complications. In laparoscopic resections of the colon, complications do not negatively affect long-term oncologic outcomes.

Adnexal masses in patients with colorectal cancer

OBJECTIVE

To evaluate the clinicopathological features and outcomes of patients undergone surgery for benign and metastatic adnexal masses during the surveillance of colorectal cancer (CRC).

METHODS

A single institute retrospective study involving 90 patients diagnosed with CRC that undergone surgery at Hacettepe University Hospital between 2000-2018. Clinicopathological and survival data was obtained from hospital records.

RESULTS

Elevated blood levels of CEA (HR, 1.23; 95 % CI: 1.03-1.24; p = 0.01), adnexal masses larger than 5 cm (HR, 3.296; 95 % CI: 1.527-7.076; p = 0.002), bilaterality of adnexal mass (HR, 2.200; 95 % CI: 2.464-11.969; p = 0.001) and high PCI score (HR, 0.150; 95 % CI: 0.044-0.479; p = 0.01) were found to be significantly associated with ovarian metastasis. There was a significant difference in overall survival (OS), with respect to complete and incomplete resection in adnexal surgery of ovarian metastasis (46.6 vs. 29.6 months; p = 0.004). The median survival time was 32.8 months for patients with ≤ 24 months interval time to adnexal metastasis surgery, and 48.5 months for patients with >24 months interval time to adnexal metastasis surgery (p = 0.001).

CONCLUSION

This study showed that numerous clinicopathological variables such as bilaterality and size of adnexal mass, serum blood levels of CEA and PCI score may have a significant impact on the prediction and management of ovarian masses diagnosed during CRC surveillance. Complete resection and interval time to adnexal surgery is significantly associated with OS.

Mucinous Histology Might Be an Indicator for Enhanced Survival Benefit of Chemotherapy in Stage II Colon Cancer

Background: It was a difficult question to identify candidates who would benefit most from adjuvant chemotherapy in stage II colon cancer because of the paucity of relevant conclusive clinical trial results. We aimed to assess if mucinous adenocarcinoma (MUA) could be an indicator for the efficacy of adjuvant chemotherapy in stage II colon cancer.

Methods:Using SEER^*Stat software V.8.3.5, eligible patients were then recruited from the SEER database. A χ² test was applied to compare the distribution of different categorical variables between nonmucinous adenocarcinoma (NMUA) and MUA groups. We then used the Kaplan–Meier method to analyze overall survival (OS) of different histological types in stage II colon cancer, and the log-rank test was then used to assess the OS differences. The Cox proportional regression risk models were also built in our analyses to eliminate potential crossed bias from other prognostic factors.

Results:A total of 50,065 patients diagnosed with stage II colon cancer were recruited from the SEER database from 2004 to 2011; all the patients were divided into two groups, including NMUA (n = 44,785) and MUA (n = 5,280). The Cox analysis of the histological type indicated that the survival difference between MUA and NMUA failed to reach statistical significance in stage II colon cancer (P = 0.360). In NMUA, patients treated with adjuvant chemotherapy were independently associated with 37.2% decreased risk of overall mortality compared with those not [hazard ratio (HR) = 0.628, 95% confidence interval (CI) = 0.601-1.656, P < 0.001]; in MUA, the number increased to 41.5% (HR = 0.585, 95% CI = 0.515-0.665, P < 0.001).

Conclusions:Our study showed that the survival difference between MUA and NMUA failed to reach statistical significance in stage II colon cancer. More importantly, our study had provided the first evidence that chemotherapy would offer higher survival improvement in MUA compared with NMUA in stage II colon cancer; mucinous histology might be an indicator for enhanced survival benefit of chemotherapy in stage II colon cancer.

MicroRNA-196b-5p promotes malignant progression of colorectal cancer by targeting ING5

Background

miR-196b-5p expression is deregulated in many malignant tumors. Although miR-196b-5p has been implicated in the malignant transformation of colorectal cancer, its role in this specific type of cancer has not been fully explored. Thus, the present study was aimed to examine the cellular function of miR-196b-5p and its role in malignant biological behavior in colorectal cancer.

Methods

miR-196b-5p expression was measured in colorectal cancer tissues and cell lines using quantitative real-time PCR. Cell counting kit-8 (CCK-8) assay and Transwell assay were used to detect proliferation, migration, and invasion in cell lines, whereas flow cytometry was applied to study apoptosis. Western blot analysis was performed to measure the protein levels. Dual luciferase reporter assay was used to investigate the interaction between miR-196b-5p and ING5. Tumor formation was evaluated in mice.

Results

MiR-196b-5p was abundantly expressed in colorectal cancer tissues and cell lines, whereas ING5 was expressed at low levels. MiR-196b-5p was successfully overexpressed or knocked down in colorectal cancer cells. We found that miR-196b-5p overexpression significantly accelerated the proliferation, cell cycle, migration and invasion, while inhibited cell apoptosis in colorectal cancer cells. However, miR-196b-5p inhibitor showed the opposite effects. Moreover, ING5 overexpression or knockdown was successfully performed in colorectal cancer cells. ING5 overexpression suppressed proliferation, migration, invasion, the phosphorylation of PI3K, Akt as well as MEK, and promoted cell apoptosis, which could be reversed by ING5 knockdown. Additionally, ING5 was identified as a target of miR-196b-5p through bioinformatics analysis and a luciferase activity assay. Furthermore, ING5 knockdown could attenuate the decrease in proliferation, migration, invasion, and the protein levels of p-PI3K, p-Akt, and p-MEK, which were induced by miRNA-196b-5p inhibitor. Besides, miR-196b-5p knockdown inhibited tumor growth, whereas ING5 knockdown elevated it in vivo.

Conclusions

In conclusion, miR-196b-5p promotes cell proliferation, migration, invasion, and inhibits apoptosis in colorectal cancer by targeting ING5.

How Soon Should Patients With Colon Cancer Undergo Definitive Resection?

BACKGROUND

Timing of surgery has been shown to affect outcomes in many forms of cancer, but definitive national data do not exist to determine the effect of time to surgery on survival in colon cancer.

OBJECTIVE

This study aimed to determine whether a delay in definitive surgery in colon cancer significantly affects survival.

DATA SOURCES

A retrospective cohort study using 2 independent population-based databases, The Surveillance, Epidemiology, and End Results Medicare-linked database and the National Cancer Database, was performed.

STUDY SELECTION

All patients had American Joint Committee on Cancer stage 1 through 3 colon cancer. Patients were more than 18 years of age in the National Cancer Database cohort and older than 66 years of age in the Medicare cohort. Patients had a minimum of 3 years of follow-up.

MAIN OUTCOME MEASURES

The main outcome was overall survival as a function of time between diagnosis and surgery in 4 intervals (1-2, 3-4, 5-6, >6 weeks).

RESULTS

The Medicare cohort demonstrated an adjusted 5-year survival of 8% to 14% higher in patients with a surgical delay between 3 and 6 weeks, with significantly lower hazard ratios in that interval. The National Cancer Database cohort demonstrated an adjusted 5-year survival of 9% to 16% higher in patients with surgery 3 to 6 weeks after diagnosis, with comparatively similar improvements in survival hazard.

LIMITATIONS

Because this was a retrospective study of administrative databases, with Medicare data limited to billing data, the causality of outcomes must be interpreted with caution.

CONCLUSIONS

The ideal timing of definitive resection in colon cancer is between 3 and 6 weeks after initial diagnosis. All efforts should be made for patients to obtain definitive surgery within this interval to achieve a modest but significant improvement in overall survival. See Video Abstract at http://links.lww.com/DCR/B76. ¿CUÁNDO DEBEN SOMETERSE LOS PACIENTES CON CÁNCER DE COLON A UNA RESECCIÓN DEFINITIVA?: Se ha demostrado que el momento de la cirugía afecta los resultados en muchas formas de cáncer, pero no existen datos nacionales definitivos para determinar el efecto del tiempo hasta la cirugía en la supervivencia en el cáncer de colon.Determinar si un retraso en la cirugía definitiva en el cáncer de colon afecta significativamente la supervivencia.Un estudio de cohorte retrospectivo que utiliza dos bases de datos independientes basadas en la población; Se realizó la base de datos vinculada a la vigilancia, la epidemiología y los resultados finales y la base de datos nacional del cáncer.Pacientes con cáncer de colon en estadíos 1 a 3 del Comité Estadounidense Conjunto sobre el Cáncer. Los pacientes tenían más de 18 años en la cohorte de la National Cancer Database y más de 66 años en la cohorte de Medicare. Los pacientes tuvieron un mínimo de 3 años de seguimiento.El resultado principal fue la supervivencia general en función del tiempo entre el diagnóstico y la cirugía en 4 intervalos (1-2, 3-4, 5-6, y mas de 6 semanas).La cohorte de Medicare demostró una supervivencia ajustada de 5 años de 8 a 14% más en pacientes con un retraso quirúrgico entre 3 a 6 semanas, con razones de riesgo significativamente más bajas en ese intervalo. La cohorte de la National Cancer Database demostró una supervivencia ajustada a 5 años de 9 a 16% más en pacientes con cirugía de 3 a 6 semanas después del diagnóstico, con mejoras comparativamente similares en el riesgo de supervivencia.Dado que este fue un estudio retrospectivo de bases de datos administrativas, con datos de Medicare limitados a datos de facturación, la causalidad de los resultados debe interpretarse con precaución.El momento ideal para la resección definitiva en el cáncer de colon es entre tres y seis semanas después del diagnóstico inicial. Se deben hacer todos los esfuerzos para que los pacientes obtengan una cirugía definitiva dentro de este intervalo para lograr una mejora modesta pero significativa en la supervivencia general. Consulte Video Resumen en http://links.lww.com/DCR/B76.

Impact of perioperative transfusions and sepsis on long-term oncologic outcomes after curative colon cancer resection. A retrospective analysis of a prospective database

OBJECTIVE

Intra-abdominal septic complications (IASC) affect short-term outcomes after surgery for colon cancer. Blood transfusions have been associated with worse short-term results. The role of IASC and blood transfusions on long-term oncologic results is still debated. This study aims to assess the impact of these two variables on survival after curative colon cancer resection.

PATIENTS AND METHODS

Retrospective analysis of a prospectively maintained database of patients who underwent curative surgery for colon cancer at a university hospital, between 1993 and 2010. Cox regression was used to identify the role of IASC and transfusions (alone and combined) on local recurrence (LR), disease-free survival (DFS), and cancer-specific survival (CSS).

RESULTS

Out of the 1686 patients analyzed, 1277 fit in the inclusion criteria. Colorectal surgeons performed the procedure in 82.2% of the patients. Blood transfusions were administered to 25.8% of the patients. Thirty-day complication and mortality rates were 34.5% and 6.1%. IASC occurred in 9.9%. The mean follow-up was 66 months. The 5-year rates of LR, DFS, and CSS were 7%, 79.8%, and 85.1%. The year of surgery and pT (Hazard ratio 9.35, 95% CI 1.23-70.9, for T4) and pN (Hazard ratio 2.57, 95% CI 1.39-4.72, for N2) stages were independent risk factors for LR. The same variables, bowel obstruction and surgeries performed by surgeons not specialized in colorectal surgery, were also associated with worse DFS and CSS. IASC and blood transfusions were not associated with LR, DFS, and CSS, whether alone or combined.

CONCLUSIONS

IASC and transfusions were not associated with worse oncological outcomes after curative colon cancer surgery per se. Other factors were more important predictors of survival.

Emergency Surgery for Obstructive Colon Cancer in Elderly Patients: Results of a Multicentric Cohort of the French National Surgical Association

BACKGROUND

Although elderly patients constitute most of the patients undergoing surgery for obstructed colon cancer, available data in the literature are very limited.

OBJECTIVE

The purpose of this study was to assess the management and outcomes of elderly patients treated for obstructed colon cancer.

DESIGN

This was a multicenter, retrospective cohort study.

SETTINGS

Between 2000 and 2015, 2325 patients managed for an obstructed colon cancer in member centers of the French National Surgical Association were identified. Data were collected by each center on a voluntary basis after institutional approval. Bowel obstruction was defined clinically and confirmed by imaging.

PATIENTS

Three age groups were defined, including patients <75 years, 75 to 84 years, and ≥85 years.

MAIN OUTCOME MEASURES

Postoperative and oncologic results in elderly patients with an obstructed colon cancer were measured. Relative survival was calculated as the ratio of the overall survival with the survival that would have been expected based on the corresponding general population.

INTERVENTIONS

A total of 302 patients (13%) underwent colonic stent insertion, and 1992 (87%) underwent surgery as emergency procedure.

RESULTS

A total of 2294 patients were analyzed (<75 y, n = 1200 (52%); 75-84 y, n = 650 (28%); and ≥85 y, n = 444 (20%)). Elderly patients were more likely to be women (p < 0.0001), to have proximal colon cancer (p < 0.0001), and to have a higher incidence of comorbidities (p < 0.0001). The use of colonic stent or the type of surgery was identical regardless of age. In patients with resected colon cancer, elderly patients had less stage IV disease (p < 0.0001). The absence of tumor resection (p < 0.0001) and definitive stoma rate increased with age (p < 0.0001). Postoperative mortality and morbidity were significantly higher in elderly patients (p < 0.0001), but surgical morbidity was similar across age groups (p = 0.60). Postoperative morbidity was correlated to the 6-month mortality rate in elderly (p < 0.0001). Overall and disease-free survivals were significantly lower in more elderly patients (p < 0.0001) but relative survival was not (p = 0.09).

LIMITATIONS

It is quite difficult to know how to interpret these data as a whole, given the inherent bias in the study population, lack of ability to stratify by performance status, and long study period duration.

CONCLUSIONS

Elderly patients have high morbidity with lower survival in the highest age ranges of elderly subgroups. These data should be considered when deciding on an operative approach. See Video Abstract at http://links.lww.com/DCR/A964.

Randomized clinical trial of accelerated enhanced recovery after minimally invasive colorectal cancer surgery (RecoverMI trial)

BACKGROUND

Minimally invasive surgery (MIS) and enhanced recovery protocols (ERPs) have improved postoperative recovery and shortened length of hospital stay (LOS). Telemedicine technology has potential to improve outcomes and patient experience further. This study was designed to determine whether the combination of MIS, ERP and a structured telemedicine programme (TeleRecovery) could shorten total 30-day LOS by 50 per cent.

METHODS

This was a phase II prospective RCT at a large academic medical centre. Eligible patients aged 18-80 years undergoing minimally invasive colorectal resection using an ERP were randomized after surgery. The experimental arm (RecoverMI) included accelerated discharge on postoperative day (POD) 1 with or without evidence of bowel function and a televideoconference on POD 2. The control arm was standard postoperative care. The primary endpoint was total 30-day LOS (postoperative stay plus readmission/emergency department/observation days). Secondary endpoints included patient-reported outcomes measured by EQ-5D-5L™, Brief Pain Inventory (BPI) and a satisfaction questionnaire.

RESULTS

Thirty patients were randomized after robotic (21 patients) or laparoscopic (9) colectomy, including 14 patients in the RecoverMI arm. Median 30-day total LOS was 28·3 (i.q.r. 23·7-43·6) h in the RecoverMI arm and 51·5 (43·8-67·0) h in the control arm (P = 0·041). There were no differences in severe adverse events or EQ-5D-5L™ score between the study arms. The BPI revealed low pain scores regardless of treatment arm. Satisfaction was high in both arms.

CONCLUSION

In patients having surgery for colorectal neoplasms, the trimodal combination of MIS, ERP and TeleRecovery can reduce 30-day LOS while preserving patients' quality of life and satisfaction. Registration number: NCT02613728 ( https://clinicaltrials.gov).

MicroRNA (miR)-597-5p Inhibits Colon Cancer Cell Migration and Invasion by Targeting FOS-Like Antigen 2 (FOSL2)

Our previous work had shown that FOS-like antigen 2 (FOSL2) is regulated by miR-143-5p in colorectal cancer (CRC). Given that it has been shown by others that FOSL2 is also a target of miR-597-5p in breast adenocarcinoma, the objective of the current work was to determine whether FOSL2 is regulated by miR-597-5p in CRC and the role of miR-597-5p in CRC. MiR-597-5p expression was determined in RNA obtained from 30 paired samples of colon cancer and tumor adjacent normal tissue, as well as in the LoVo (CRC cell line) and FHC (normal colonic epithelial cells) by quantitative real time polymerase chain reaction (qRT-PCR). MiR-597-5p expression was significantly downregulated in both CRC tissue and LoVo cells. Reporter assays using wild-type and miR-597-5p seed mutant FOSL2 confirmed that FOSL2 is a bona fide target of miR-597-5p. Modulating miR-597-5p expression levels in FHC and LoVo cells using antagomir and mimic, respectively, impacted expression of epithelial and mesenchymal cell markers as well as in vitro migration and invasion, without any effect on cell proliferation, showing that miR-597-5p functions as a suppressor of epithelial to mesenchymal transition. Restoration of FOSL2 expression rescued pro-metastatic functional properties of LoVo cells conforming that effect of miR-597-5p was being mediated by targeting FOSL2. Xenograft assays in athymic nude mice showed that miR-597-5p mimic did not reduce tumor incidence or growth in LoVo cells. However, using a hepatic metastasis model showed that miR-597-5p mimic can significantly prevent hepatic metastatic nodule formation as well as FOSL2 expression in these metastatic nodules. Importantly, FOSL2 mRNA and miR-597-5p expression was found to be inversely correlated in an independent cohort of 21 CRC patients Cumulatively our results show that miR-597-5p functions as a suppressor of metastatic progression in CRC by targeting FOSL2. Replenishment of miR-597-5p can be a potential therapeutic target where its expression along with FOSL2 can serve as potential diagnostic markers in CRC.

Prognostic Impact of pT Stage and Peritoneal Invasion in Locally Advanced Colon Cancer

BACKGROUND

TNM stage has been identified as an independent variable for local recurrence and survival after colon cancer resection. It is still unclear whether peritoneal invasion (pT4a) is a risk factor for adverse oncologic outcome or whether these patients have better results compared with contiguous organs infiltration (pT4b), independent from nodal status (pN).

OBJECTIVE

The purpose of this study was to analyze whether peritoneal invasion is an independent risk factor for worse oncologic outcome after curative colon cancer resection.

DESIGN

This was a retrospective analysis with multivariate regression of a prospective database, according to Strengthening the Reporting of Observational Studies in Epidemiology Statement.

SETTINGS

The study was conducted in a specialized colorectal unit of a tertiary hospital.

PATIENTS

A consecutive series of pT3-pT4a-pT4b patients with colon cancer who underwent curative surgery (1993-2010) were included, and patients with metastasis were excluded.

MAIN OUTCOME MEASURES

A multivariate Cox regression analysis was performed to assess independent risk factors for 5-year local recurrence, peritoneal carcinomatosis-like recurrence, disease-free survival, and cancer-specific survival.

RESULTS

A total of 1010 patients were analyzed (79.3% pT3, 9.9% pT4a, and 10.8% pT4b). At diagnosis, 22.0% had obstructive symptoms, and 10.5% had bowel perforation. A total of 72.2% of the surgeries were elective, and in 15.6% en bloc resection of contiguous organs was performed. Median follow-up was 62 months (38-100 mo). For the whole group, 5-year actuarial rates were 8.8% for local recurrence, 2.5% for peritoneal carcinomatosis, 75.5% for disease-free survival, and 81.8% for cancer-specific survival. At multivariate analysis, pT4a stage was an independent risk factor for local recurrence (p = 0.002; HR = 3.1), peritoneal carcinomatosis (p = 0.02; HR = 4.9), worse disease-free survival (p = 0.002; HR = 1.9), and cancer-specific survival (p = 0.001; HR = 2.2). When considering only the 566 patients with ≥12 nodes identified, T stage was still associated with higher local recurrence (p = 0.04) and carcinomatosis rate (p = 0.04), as well as worse disease-free (p = 0.009) and cancer-specific survival (p = 0.014).

LIMITATIONS

This was a retrospective, single-center study.

CONCLUSIONS

pT4a stage is an independent risk factor for worse oncologic outcome after curative colon cancer resection compared with pT3 and pT4b stages. The current pT4a-pT4b classification should be reconsidered. Of note, even in pT4a patients, 5-year carcinomatosis rate does not exceed 6%. See Video Abstract at http://links.lww.com/DCR/A926.

Post-operative computed tomography scan – reliable tool for quality assessment of complete mesocolic excision

BACKGROUND

Quality control in colon cancer surgery is an ongoing debate ever since standardization proved to be highly efficient in improving survival in rectal cancer. Complete mesocolic excision (CME) is widely acclaimed as the new gold-standard in colon cancer resections, thus it is imperative to establish quality criteria of CME in order to make it easily understood and verified by surgeons worldwide. One simple and reproducible tool could be the measurement of arterial stumps postoperatively and a straightforward way to test its reliability is to test it in a comparative study between CME and non-CME surgery.

AIM

To validate arterial stump measurement as a surgical quality tool by comparing CME with conventional radical colectomies.

METHODS

This was a retrospective study, carried out on a prospective database. We collected data from two groups of patients, divided according to standard CME with D2 central vascular ligation (group A) and non-standardized surgery (group B). The two groups were compared with regard to the arterial stump length after right- and left-sided colectomies for colon cancer. The actual stump lengths of the ileocolic artery (ICA) and inferior mesenteric artery (IMA) were compared with their theoretical best D2 position of predicted ligation levels (D₂PLLs) for calculating the potential for improvement. Measurements on follow-up computed tomography scans were carried out by three observers. Pathological data were recorded (specimen length, lymph node yield) and correlated with stump length.

RESULTS

We analysed 58 colectomies. The stump lengths (mean ± SD) in group A were 16.97 ± 4.77 mm for ICA and 31.70 ± 15.71 mm for IMA, whereas group B had 49.93 ± 20.29 mm for ICA and 67.24 ± 28.71 mm for IMA. Shorter lengths were obtained in group A, by a mean difference of 35.66 mm (χ² = 27.38, P < 0.001), which was significant for all types of colectomies. Except for a 5.85 ± 4.71 mm difference for right colectomies, all the ligations from group A significantly reached their potential height (0.26 ± 12.18 mm from D₂PLL; χ² = 0.005, P = 0.944). Apart from three left colectomies, group B failed to reach D₂PLL, by a mean difference of 32.14 ± 26.15 mm (χ² = 21.77, P < 0.001). The calculated improvement potentials were significantly shorter in group A than in group B, by a mean of 31.88 mm (χ²= 22.13, P < 0.001). The large spread of results in group B showed that there is significant variability (P = 0.004) when compared to standard surgery. Significant correlations were found between stump length, specimen length and number of lymph nodes (P = 0.018 and P = 0.008 respectively). No statistical difference was found between observers’ measurements (P = 0.866).

CONCLUSION

Arterial stump monitoring is a significant step in defining surgical quality, as longer stumps contain residual mesocolic tissue and correlate with major prognostic factors.

[Standardization of surgical care for malignant colonic obstruction]

AIM

To standardize surgical care for malignant colonic obstruction.

MATERIAL AND METHODS

There were 572 patients with malignant colonic obstruction: 247 of them were hospitalized in 2011-2013 (I group); 325 - in 2014-2017 (group II). Forty-six patients underwent medication; 302 - acute resection; 141 - stoma construction; 83 - stent deployment. Elective surgery and radiation or chemotherapy was performed after 0.5-6 months in 110 patients of group II. Acute resection was more common in I group, elective resection - in group II. Early and long-term results including Kaplan-Meier 3-year overall survival were compared in both groups.

RESULTS

Complications occurred in 46.69% (group I) and 21% (group II). Postoperative mortality was significantly higher in group I compared with II group: 26.11 and 10.33%, respectively. Three-year overall survival was higher in group I compared with group II: 0.82 and 0.69, respectively.

CONCLUSION

Advisability of new two-stage surgical standard is confirmed for malignant colonic obstruction. Stoma formation and stenting may be a valid alternative in some patients with malignant colonic obstruction due to significantly lower postoperative mortality.

The Impact of a Multivisceral Resection and Adjuvant Therapy in Locally Advanced Colon Cancer

BACKGROUND

Multivisceral resection for locally advanced colon cancer is mandatory to achieve complete tumor resection. We aimed to determine if local multivisceral resections (LMR) for pT4 and pT3 tumors impact perioperative and long-term oncological outcomes.

METHODS

All stage II or III colon cancer patients who had surgery between 2004 and 2014 were identified. We analyzed patients with non-multivisceral resections (NMR) for pT4 tumors vs. pT4-LMR. In addition, outcomes were compared to both NMR and LMR pT3 patients.

RESULTS

LMR was performed in 55 (29.7%) of all patients with pT4 tumors and in 48 (8.9%) of all patients with pT3 tumors. The most commonly involved areas of extension were the abdominal wall and the small intestine. Transverse colon cancer was correlated with LMR. Morbidity rates were comparable between NMR and LMR, with the exception of higher rates of blood transfusion and postoperative ileus. Over one third of all pT4-NMR patients developed recurrent disease, which was higher compared to all other groups. Subsequently, overall and disease-specific survival, as well as disease-free survival (DFS), was worse for pT4-NMR, even after adjustment for pTN-staging, adjuvant therapy, and R0 resection. Furthermore, when analyzing only curative resections, radial margin < 1 cm along with nodal disease was independent predictor for worse DFS. Long-term outcomes were comparable between pT4-LMR and pT3 patients.

CONCLUSIONS

Multivisceral resection for locally advanced colon cancer preserves long-term oncological outcomes without increased postoperative morbidity. Moreover, LMR in pT3 tumors does not contribute to postoperative morbidity. Our study underlines the feasibility and importance of performing LMR when locally advanced cancer is suspected.

Treatment of Patients With Early-Stage Colorectal Cancer: ASCO Resource-Stratified Guideline

PURPOSE

To provide resource-stratified, evidence-based recommendations on the treatment and follow-up of patients with early-stage colorectal cancer.

METHODS

ASCO convened a multidisciplinary, multinational Expert Panel that reviewed existing guidelines and conducted a modified ADAPTE process and a formal consensus process with additional experts for one round of formal ratings.

RESULTS

Existing sets of guidelines from 12 guideline developers were identified and reviewed; adapted recommendations from six guidelines form the evidence base and provide evidence to inform the formal consensus process, which resulted in agreement of 75% or more on all recommendations.

RECOMMENDATIONS

For nonmaximal settings, the recommended treatments for colon cancer stages nonobstructing, I-IIA: in basic and limited, open resection; in enhanced, adequately trained surgeons and laparoscopic or minimally invasive surgery, unless contraindicated. Treatments for IIB-IIC: in basic and limited, open en bloc resection following standard oncologic principles, if not possible, transfer to higher-level facility; in emergency, limit to life-saving procedures; in enhanced, laparoscopic en bloc resection, if not possible, then open. Treatments for obstructing, IIB-IIC: in basic, resection and/or diversion; in limited or enhanced, emergency surgical resection. Treatment for IIB-IIC with left-sided: in enhanced, may place colonic stent. Treatment for T4N0/T3N0 high-risk features or stage II high-risk obstructing: in enhanced, may offer adjuvant chemotherapy. Treatment for rectal cancer cT1N0 and cT2n0: in basic, limited, or enhanced, total mesorectal excision principles. Treatment for cT3n0: in basic and limited, total mesorectal excision, if not, diversion. Treatment for high-risk patients who did not receive neoadjuvant chemotherapy: in basic, limited, or enhanced, may offer adjuvant therapy. Treatment for resectable cT3N0 rectal cancer: in enhanced, base neoadjuvant chemotherapy on preoperative factors. For post-treatment surveillance, a combination of medical history, physical examination, carcinoembryonic antigen testing, imaging, and endoscopy is performed. Frequency depends on setting. Maximal setting recommendations are in the guideline. Additional information can be found at www.asco.org/resource-stratified-guidelines .

NOTICE

It is the view of the American Society of Clinical Oncology that health care providers and health care system decision makers should be guided by the recommendations for the highest stratum of resources available. The guidelines are intended to complement but not replace local guidelines.

[The optimal terms of the second stage of treatment of patients with malignant colonic obstruction]

AIM

To determine the optimal terms of the second stage of treatment of patients with malignant colonic obstruction.

MATERIAL AND METHODS

There were 110 patients with colorectal cancer stage T_3-4N₀M₀ (groups I-III, n=69) and T_3-4N_0-2M_0-1 (group IV, n=41). Everybody has been previously treated for colonic obstruction 0,5-6 months ago: stoma in 62 cases, stenting - in 48 cases. Elective radical surgery and radiotherapy and/or chemotherapy were applied in 2 (I group, n=23), 3 (II, n=23), 4 (III, n=23) weeks or 4-6 months (IV, n=41) after colonic decompression. The optimal terms of radical surgery are determined depending on CT-data, histological examination.

RESULTS

Bowel wall thickness was significantly higher in I-II groups compared with III-IV groups: 3.7; 2.5; 1.9; 1.7, respectively (p≤0,5). The maximum number of tumor emboli was found in III-IV groups. Signs of focal colitis were absent in III-IV groups.

CONCLUSION

The expediency of the new surgical standard is confirmed. Bridging strategy (stenting and stoma) may be a valid alternative in some patients with malignant colonic obstruction due to reduced postoperative mortality. The optimal terms for resection in patients with local cancer is 4 weeks after colonic decompression, in locally advanced cancer - 4-6 months.

Survival and quality of life after surgery for colorectal cancer in the elderly: a comparative study

BACKGROUND

the aim of this study was to analyze the clinical results of the multidisciplinary management of elderly patients with colorectal cancer in a single center and to describe postoperative quality of life.

METHODS

a comparative study was designed to compare the results and quality of life of patients treated in our center for colon cancer, aged from 80 to 84 years (study group) compared to a control group (aged form 75 to 79 years of age). Morbidity, mortality, oncological results and quality of life were analyzed.

RESULTS

eighty-seven patients aged between 80 and 84 years of age (study group) were compared to a control group, which was formed by 91 patients aged from 75 to 79 years of age. There were no significant differences in technique and morbidity. Survival at 30 days, 90 days and at the end of follow-up (median 48 months) were similar in both groups. There were no differences in quality of life except for one item with regard to physical function (p = 0.0138).

CONCLUSION

similar clinical results and quality of life were achieved after treating elderly patients with colon cancer with a multidisciplinary management approach.

Krukenberg tumours from gastrointestinal cancers-analysis from a tertiary care centre in India

Background

Krukenberg tumour (KT) is clinically defined as any ovarian metastatic carcinoma derived from a primary malignancy (usually from the gastrointestinal tract). Our aim was to analyse the incidence, demographic profile, clinical features, management and survival of patients with KTs from gastrointestinal tract malignancies at our centre.

Methods

This was a retrospective analysis data at our centre between Jan 2015 and Dec 2017.

Results

A total of 8 patients of KTs (2 from gastric and 6 from colorectal cancers) were observed with an incidence of 0.66% in gastric and 2.90% in colorectal cancers. The mean age of all the patients was 40 years (44 in gastric and 39 in colorectal group) and most of them (5 out of 8) occurred in premenopausal women. They were also most commonly bilateral (6 out of 8) and synchronous (6 out of 8). Surgical debulking was possible in 7 patients and all patients underwent systemic chemotherapy. Interestingly, 4 patients in the colorectal KT group with metastasis limited to ovary alone managed by surgical debulking and chemotherapy had a significantly higher 1-year survival compared to the others with peritoneal disease are alive at an average of 14.5 months.

Conclusions

The incidence of KTs from colorectal cancers is on the rise. KTs from colorectal cancers and KTs without peritoneal metastases have a better prognosis showing significantly higher 1-year survival rates following complete surgical resection and systemic chemotherapy.

Complete resection of colorectal cancer with ovarian metastases combined with chemotherapy is associated with improved survival

BACKGROUND

Ovarian metastases (OM) from colorectal cancer (CRC) are uncommon, and data about optimal management are lacking. The aim of this study was to examine the management and outcomes of patients with OM from CRC.

METHODS

A retrospective review of records of patients with a histopathological diagnosis of OM from CRC who were treated at Christchurch Hospital between 1 January 2000 and 31 December 2016. Data related to presentation, clinicopathological characteristics, treatment and outcomes were recorded. The primary outcomes were overall survival and disease-free survival.

RESULTS

Thirty-one patients were identified (median age 55 years, range 28-77), with a median follow-up of 23 months (range 3-84 months). Abdominal pain was the most common presenting symptom (22 patients). Synchronous OM occurred in 22 patients, 14 patients had bilateral ovarian involvement. Twenty-one patients received adjuvant chemotherapy. R0 resection was achieved in 14 patients. For all patients the 5-year disease-free and overall survival were 11% and 12%, respectively, while 5-year overall survival for R0 resections was 30%. Improved median survival was associated with negative colon resection margins (26.7 months versus 7.8 months, P = 0.03), R0 resection (30.5 months versus 23.5 months, P = 0.04), and use of adjuvant chemotherapy (28.8 months versus 8.2 months, P < 0.0001); however, on multivariate analysis adjuvant chemotherapy was the only independent factor associated with improved prognosis (P = 0.01).

CONCLUSIONS

OM from CRC are uncommon and carry a poor prognosis. Improved survival was associated with complete surgical resection of the primary tumour and metastatic disease in combination with systemic chemotherapy.

TISSUE EXPRESION OF THE GENES MUTYH AND OGG1 IN PATIENTS WITH SPORADIC COLORECTAL CANCER

BACKGROUND

MTUYH and OGG1 genes have importance in the base excision repair systems of oxidized DNA bases. Modification of the tissue expression of these genes is related to the increased risk of developing colorectal cancer.

AIM

To evaluate the tissue expression of MUTYH and OGG1 comparing normal and neoplastic tissues of patients with sporadic colorectal cancer and to correlate it with clinical and histopathological variables.

METHOD

MUTYH and OGG1 tissue expression was quantified by RT-PCR in patients with colorectal cancer and the values were compared in normal and neoplastic tissues. MUTYH and OGG1 expression was measured and normalized to the constitutive 18S gene. The level of expression of both genes was correlated with the variables: age, gender, tumor location, size of the tumor, histological type, degree of cell differentiation, invasion depth in the intestinal wall, angiolymphatic infiltration, lymph node involvement and TNM staging.

RESULTS

Was found downregulation of both genes in neoplastic when compared to normal tissue. There was downregulation of the MUTYH in larger tumors and in patients with angiolymphatic invasion. Tumors with more advanced TNM stages (III and IV) presented downregulation of both genes when compared to those with earlier stages (I and II).

CONCLUSION

The MUTYH and OGG1 genes present downregulation in the more advanced stages of colorectal cancer.

2017 WSES guidelines on colon and rectal cancer emergencies: obstruction and perforation

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Obstruction and perforation due to colorectal cancer represent challenging matters in terms of diagnosis, life-saving strategies, obstruction resolution and oncologic challenge. The aims of the current paper are to update the previous WSES guidelines for the management of large bowel perforation and obstructive left colon carcinoma (OLCC) and to develop new guidelines on obstructive right colon carcinoma (ORCC).

Methods

The literature was extensively queried for focused publication until December 2017. Precise analysis and grading of the literature has been performed by a working group formed by a pool of experts: the statements and literature review were presented, discussed and voted at the Consensus Conference of the 4th Congress of the World Society of Emergency Surgery (WSES) held in Campinas in May 2017.

Results

CT scan is the best imaging technique to evaluate large bowel obstruction and perforation. For OLCC, self-expandable metallic stent (SEMS), when available, offers interesting advantages as compared to emergency surgery; however, the positioning of SEMS for surgically treatable causes carries some long-term oncologic disadvantages, which are still under analysis. In the context of emergency surgery, resection and primary anastomosis (RPA) is preferable to Hartmann’s procedure, whenever the characteristics of the patient and the surgeon are permissive. Right-sided loop colostomy is preferable in rectal cancer, when preoperative therapies are predicted.

With regards to the treatment of ORCC, right colectomy represents the procedure of choice; alternatives, such as internal bypass and loop ileostomy, are of limited value.

Clinical scenarios in the case of perforation might be dramatic, especially in case of free faecal peritonitis. The importance of an appropriate balance between life-saving surgical procedures and respect of oncologic caveats must be stressed. In selected cases, a damage control approach may be required.

Medical treatments including appropriate fluid resuscitation, early antibiotic treatment and management of co-existing medical conditions according to international guidelines must be delivered to all patients at presentation.

Conclusions

The current guidelines offer an extensive overview of available evidence and a qualitative consensus regarding management of large bowel obstruction and perforation due to colorectal cancer.

Case of laparoscopic right hemicolectomy for ascending colon cancer after aortic graft replacement and revascularization of the superior mesenteric artery

A 67-year-old man who presented with a bloody stool was diagnosed with ascending colon cancer. He had previously experienced thoracic and abdominal aortic dissections, which were treated with thoracic and abdominal aortic grafts and superior mesenteric artery revascularization. We performed a laparoscopic right hemicolectomy with a D3 lymph node dissection. During the laparotomy, we identified the superior mesenteric artery and an enlarged anterior superior pancreaticoduodenal artery. Injury to the latter artery could lead to severe ischemia in multiple organs; therefore, it was crucial to identify the primary feeding artery and vascular anatomy before and during surgery. We chose the laparoscopic right hemicolectomy to avoid injuring the anterior superior pancreaticoduodenal artery and the intra-abdominal abscess. This case study was the first to describe a laparoscopic hemicolectomy after thoracic and abdominal aortic grafts and superior mesenteric artery revascularization.

Screening-detected colorectal cancers show better long-term survival compared with stage-matched symptomatic cancers

PURPOSE

the aim of this study was to compare overall and disease-free survival among patients with colorectal cancer detected via a screening program as compared to those with symptomatic cancer.

MATERIAL AND METHODS

patients diagnosed via colonoscopy (screening group) and those with clinical symptoms (non-screening) were identified from 1995 to 2014. Demographic, clinical, surgical and pathologic variables were recorded. Stage I, II and III cancers were included. Overall and disease-free survival were calculated at five and ten years after tumor resection and survival was calculated by matching both groups for cancers at stage I, II and III.

RESULTS

two hundred and fifty patients were identified as a result of screening procedures and 1,330 patients presented with symptomatic cancers. There were no significant differences in the baseline characteristics between the two groups. Pathologic stage, degree of differentiation, perineural invasion and lymphovascular invasion were lower in the screening group (p < 0.01). Overall and disease-free survival at five and ten years were higher in the screening group (p < 0.01). However, when the subjects were matched for pathologic stage, significant differences were found between the two groups with regard to stage I and III tumors. Disease-free survival in stage III at five years (79.1 vs 61.7%; p < 0.001) and ten years (79.1% vs 58.5%; p < 0.001) were significantly higher in the screening group.

CONCLUSIONS

patients with stage I and III tumors that were diagnosed via a screening program have a higher overall and disease-free survival at five and ten years.

Defining the learning curve for transanal total mesorectal excision for rectal adenocarcinoma

BACKGROUND

Early observational data suggest that this approach is safe and feasible, but it is technically challenging and the learning curve has not yet been determined. The objective of this study was to determine the number of cases required achieve proficiency in transanal total mesorectal excision (TA-TME) for rectal adenocarcinoma.

METHODS

All TA-TME cases performed from 03/2012-01/2017 at a single high-volume tertiary care institution for rectal adenocarcinoma were included. A cumulative summation (CUSUM) analysis was performed to determine the number of cases required to reach proficiency, defined as high-quality TME (complete or near-complete mesorectal envelope, negative distal (DRM), and circumferential resection (> 1 mm; CRM) margin). The acceptable and unacceptable rates of good quality TME were defined based on the incidence of high-quality TME in laparoscopic (unacceptable rate = 81.7%) and open (acceptable rate = 86.9%) arms of the ACOSOG Z6051 trial.

RESULTS

A total of 87 consecutive cases were included with mean tumor height 4.8 cm (SD 2.7) and 80% (70/87) received neoadjuvant chemoradiation. Post-operative morbidity occurred in 44% (38/87) of cases, including 21% (18/87) readmissions. Median length of stay was 4 days [IQR 3-8]. A good quality TME was performed in 95% (83/87) of cases including 98% (85/87) negative CRM, 99% (86/87) negative DRM, and 99% (86/87) complete or near-complete mesorectal envelope. CUSUM analysis reported that the good quality TME rate reaches an acceptable rate after 51 cases overall, and 45 cases if abdominoperineal resections are excluded.

CONCLUSION

TA-TME is a complex technique that requires a minimum of 45-51 cases to reach an acceptable incidence of high-quality TME and lower operative duration.

Achieving high quality standards in laparoscopic colon resection for cancer: A Delphi consensus-based position paper

AIM

To investigate the rate of laparoscopic colectomies for colon cancer using registries and population-based studies. To provide a position paper on mini-invasive (MIS) colon cancer surgery based on the opinion of experts leader in this field.

METHODS

A systematic review of the literature was conducted using PRISMA guidelines for the rate of laparoscopy in colon cancer. Moreover, Delphi methodology was used to reach consensus among 35 international experts in four study rounds. Consensus was defined as an agreement ≥75.0%. Domains of interest included nosology, essential technical/oncological requirements, outcomes and MIS training.

RESULTS

Forty-four studies from 42 articles were reviewed. Although it is still sub-optimal, the rate of MIS for colon cancer increased over the years and it is currently >50% in Korea, Netherlands, UK and Australia. The remaining European countries are un-investigated and presented lower rates with highest variations, ranging 7-35%. Using Delphi methodology, a laparoscopic colectomy was defined as a "colon resection performed using key-hole surgery independently from the type of anastomosis". The panel defined also the oncological requirements recognized essential for the procedure and agreed that when performed by experienced surgeons, it should be marked as best practice in guidelines, given the principles of oncologic surgery be respected (R0 procedure, vessel ligation and mesocolon integrity).

CONCLUSION

The rate of MIS colectomies for cancer in Europe should be further investigated. A panel of leaders in this field defined laparoscopic colectomy as a best practice procedure when performed by an experienced surgeon respecting the standards of surgical oncology.

A pooled analysis of en bloc right hemicolectomy with pancreaticoduodenectomy for locally advanced right-sided colon cancer

PURPOSE

The aim of this study was to evaluate the safety and efficacy of en bloc right hemicolectomy with pancreaticoduodenectomy (RHCPD) for locally advanced right-sided colon cancer (LARCC).

METHOD

A pooled data analysis was performed on individual patients identified from the literature and the authors' institutions. The short- and long-term outcomes were assessed.

RESULTS

Recruited in this study were 81 LARCC patients undergoing RHCPD, including 75 patients reported in the literature and 6 patients from our own institutions. R0 resection was achieved in 97.5% cases. Morbidity and the 30-day mortality rate were 53.8 and 3.7%, respectively. The median survival duration was 70.4 months, and the 1-, 3- and 5-year overall survival rates were 77.8, 64.6, and 55.2%, respectively. Multivariable analysis identified only lymph node metastasis (hazard ratio 3.474, 95% confidence interval 1.323-9.120; P = 0.011) as independent predictors of poor survival.

CONCLUSION

En bloc RHCPD for LARCC can be performed safely with a high proportion of R0 resection and a good postoperative survival outcome.

Using a Video-Laparoscope for Intraoperative Colonoscopy: An Experimental Study on Intraluminal Temperature Values and Tissue Damage

Laparoscopy systems possess remarkable heat production. Video-laparoscopy was used for colonoscopy intraoperatively in rabbits. Rod lens type laparoscopes 5 and 10 mm in diameter connected with 175 and 300-W xenon light sources were used in combination. Physiological parameters including blood pressure, pulse, oxygen saturations, and luminal temperatures were investigated during 20 minutes of colonoscopy. Thermal damage scores were obtained by histopathologic analysis of the intestinal wall. The changes were categorized as physiological and structural. Damage scores were not different when 175-W light source was used with 5- and 10-mm laparoscopes. Intraluminal heat values most increased with 300 W plus 10-mm laparoscope and caused significant increase in damage scores. Structural damage indicating tissue necrosis was not observed with any of the combination in all groups. Video-laparoscopy systems did not cause significant tissue damage when used at low and moderate levels of xenon light source in the rabbit bowel intraoperatively.