Left-sided Colorectal Carcinoma Research Articles

Management of Acute Obstruction Caused by Left-Sided Colorectal Carcinoma

Management of Acute Obstruction Caused by Left-Sided Colorectal Carcinoma

Downregulation of RIZ1 protein expression in left-sided versus right-sided primary colorectal carcinomas and their distant metastases and the association with NF-B activation

e15112 Background: Activation of NF- B leads to enhanced proliferation and the expression of anti-apoptotic proteins, which are cancer phenotypes. RIZ1 inactivation through various molecular events was linked to increased proliferation, migration induction and apoptosis inhibition in human cancer. RIZ1 frameshift mutations were recently reported to be confined to MSI-H colorectal tumors and proximal tumor origin, while its hypermethylation was not limited to MSI-H tumors. However, RIZ1 protein expression has not been evaluated in colorectal carcinoma. Methods: TMAs included 28 left-sided and 12 right-sided primary colorectal adenocarcinomas, their matched normal mucosa and their respective distant metastases. Left-sided tumors were compared to right-sided tumors for expression of RIZ1 protein and NF- B activation. RIZ1 immunostaining was scored semiquantitatively (0–3+). NF- B activation was determined by IHC detecting nuclear translocation of its p65 subunit in more than 30% tumor nuclei. Discrepant results were defined as score difference of 2. Results: RIZ1 was less expressed in tumors than in benign mucosa (p<0.0001, r=- 0.377, Chi-Square). The difference between primary vs. metastatic carcinoma was not significant. Low RIZ1 was associated with NF- B activation (p<0.0001, Linear-by-Linear). Left-sided primary tumors showed less RIZ1 protein expression than right-sided (p=0.03, Chi-Square). NF- B activation was more frequent in left-sided primary tumors and their respective metastases (35% in right vs. 67% in left; p=0.002, Chi-Square Test). RIZ1 expression and NF- B activation were almost identical in primary and their respective metastatic tumors with only 3 discrepant results for NF- B status and 2 discrepant results in RIZ1 expression. Conclusions: While RIZ1 downregulation in colorectal adenocarcinoma due to RIZ1 mutations appears to be associated with MSI-H and proximal origin, its protein expression appears to be downregulated more often in distal tumors. NF- B activation is strongly associated with lower RIZ1 protein expression in colorectal adenocarcinoma. No significant financial relationships to disclose.

Total colectomy: Options in management of acute obstruction of the left-side colon

Emergency colorectal surgery has been associated with a high morbidity and mortality rate. The current trend for the management of obstruction of left-sided colorectal carcinoma favours primary resection and anastomosis, as a safe and acceptable approach to selected patients. Retrospective review of 81 patients (46 male and 35 female, mean 64 years). Morbidity after emergency total colectomy was 21%, and mortality was 6%. There were 6 anastomotic complications (2 anastomotic disruptions and 4 anastomotic leaks). Mean hospital stay was 13 days. 82% patients had adequate continence. Traditional approach for left-sided colon obstruction is three-stage procedure (Bloch-Paul-Mikulicz). The idea of removing dilated colon proximal to an obstructing tumor is not new, since Lane suggested this option in 1914. In 1965 Hughes and Cuthberson described their experience with 12 patients. At the moment of laparotomy 20% patients had advanced malignant disease. The cumulative morbidity and mortality are high in three-stage procedure. Three-stage approach is associated with high permanent colostomy rate. One-stage resection with primary anastomosis of the obstructed left-sided colon is a safe alternative to staged procedures. Emergency radical resection can be safely performed in majority of patients with left-colon obstruction. Total colectomy with anastomosis is a suitable procedure for treating left-sided colonic obstruction provided that pelvic floor is adequate. Total colectomy has low mortality, acceptable morbidity and good quality of life. The success of the surgery depends on the selection of patients.

Oncological Safety of a Metallic Stent for a Left-sided Obstructive Colorectal Carcinoma

Purpose: There is a controversy about the treatment of left-sided obstructive colorectal cancer. Recently, experience using an expandable metallic stent for relief of the obstruction has been increasing, but its oncological safety has not been confirmed. Therefore, we designed this study to evaluate the oncological safety of a metallic stent for the treatment of left-sided obstructive colorectal cancer. Methods: Forty-six patients with left-sided obstructive colorectal cancer who underwent a curative resection from 1994 to 2004, were retrospectively evaluated. Nineteen emergency operations (1994～2003) and 27 metallic stent insertions (2000～2004) were compared based on clinicopathologic features, postoperative complications, recurrence rates, and survival rates. Results: There were no significant differences in age, location, sex, and recurrence rate between the two groups. The complication rate in the emergency group was higher than it was in the stent group, but this difference was not statistically significant (26.3% vs. 14.8%; P=0.33). The overall and the disease-free survival rates were not significantly different. Conclusions: Because there was no significant differences in survival rate and recurrence rate between the two groups, metallic stent insertion can be used safely in the preoperative treatment of obstructive left-sided colorectal cancer.

Endolaparoscopic Left Hemicolectomy and Synchronous Laparoscopic Radical Nephrectomy for Obstructive Carcinoma of the Descending Colon and Renal Cell Carcinoma

Colorectal self-expandable metal stents (SEMS) have been used successfully as preoperative bridges to surgery for obstructive left-sided colorectal carcinoma. Endoscopic relief of the obstruction allows for full bowel preparation and accurate preoperative staging. A laparoscopic approach, considered by many to be contraindicated in the presence of obstruction, becomes feasible after endoscopic decompression. We present a case of obstructive carcinoma of the descending colon successfully treated with endoscopic decompression with colorectal SEMS. Subsequent staging with computed tomography revealed a renal cell carcinoma in the left kidney. Synchronous laparoscopic resection of the two carcinomas was performed, with no morbidity. To the best of our knowledge, this is the first report of endolaparoscopic left hemicolectomy and synchronous laparoscopic radical nephrectomy for obstructive carcinoma of the descending colon and renal cell carcinoma. The advantages of colorectal SEMS and the endolaparoscopic approach in managing obstructive colorectal carcinoma are discussed.

左側大腸癌イレウスに対する経肛門的イレウス管の有用性と問題点

左側大腸癌イレウスに対する経肛門的イレウス管の有用性と問題点

Emergency resection and primary anastomosis for left-sided obstructing colorectal carcinoma in the elderly.

Emergency colorectal surgery in the elderly has been associated with a high mortality rate. Although the current trend for the management of obstructing left-sided colorectal carcinoma favours primary resection and anastomosis, the safety and benefits of this approach in the elderly have not been studied. Some 57 elderly (aged more than 70 years) and 59 younger patients underwent emergency resection of an acutely obstructing left-sided colorectal carcinoma. Postoperative results in the two groups were compared. The primary resection rate was 95 per cent in the elderly and 89 per cent in younger patients (P = 0.70), with a primary anastomosis rate of 84 per cent and 78 per cent respectively (P = 0.64). Elderly patients had a significantly higher incidence of premorbid risk factors and postoperative cardiorespiratory complications but no increase in surgical complications. Anastomotic leaks occurred in 6 per cent of the elderly and 4 per cent of younger patients (P = 0.65), and the hospital mortality rate was 9 and 5 per cent respectively (P = 0.48). Emergency resection and primary anastomosis for left-sided obstructing colorectal carcinoma can be performed with favourable outcome in the elderly and should be the treatment of choice in most elderly patients.

Intra-operative injection of Patent Blue V dye to facilitate nodal staging in colorectal cancer.

Routine histopathology may understage colorectal cancer by failing to detect involved lymph nodes. This study examined the feasibility of dye staining those lymph nodes most likely to harbour metastases. Patent Blue V dye 2.5% was injected intra-operatively into left-sided colorectal carcinomas prior to resection in 19 patients. Blue-stained nodes were found in 12/19 patients (63%). Examination of blue-stained nodes alone correctly identified overall nodal status in 11 (92%) of these 12 patients. The technique needs to be refined further. Nonetheless, intra-operative lymph node staining using blue dye offers the prospect of improving the ease and accuracy of nodal staging in colorectal cancer.

Emergency one-stage surgery for obstructing left-sided colorectal carcinomas.

A one-stage operation for obstructing left-sided colorectal carcinoma remains controversial. This study was performed to compare our surgical management of patients with left-sided colorectal cancer (at or distal to splenic flexure) obstruction presenting to the Kaohsiung Medical University Hospital from January 1995 to December 2000. Ninety-six patients underwent immediate operation within 24 hours of admission. Of these, 73 patients (76%) who underwent immediate tumor resection and anastomosis in one stage after appropriate resuscitation were enrolled into our study. In one-stage operation subtotal coloectomy with ileocolic or ileorectal anastomosis (group 1) was performed in 46 patients (63%), and intraoperative bowel preparation followed by immediate resection (group 2) was undertaken in 27 patients (37%). In comparing the two groups, there was no significant difference in the postoperative mortality (8.7% in group 1 vs. 7.4% in group 2) or cumulative 5-year survival rate (36.7% in group 1 vs. 35.7% in group 2) (all p > 0.05). However, mean operation time (178 +/- 12 min in group 1 vs. 238 +/- 12 min in group 2) and postoperative wound infection rate were significantly lower (10.9% in group 1 vs. 29.6% in group 2). The incidence of postoperative diarrhea was more prominent in the group 1 than group 2 (32.6% in group 1 vs. 11.1% in group 2) (all p < 0.05). The results of our current study showed that primary resection and anastomosis by subtotal colectomy is an acceptable means for the treatment of patients with obstructing left-sided colorectal carcinomas when the patient's condition is feasible.

K-ras mutations, rectal crypt cells proliferation, and meat consumption in patients with left-sided colorectal carcinoma.

It has been suggested that N-nitroso compounds derived from meat may increase the risk of K-ras mutations in the human colon. We sought evidence of associations between red meat consumption, frequency and type of K-ras mutations in resected tumours, and the rate of crypt cell proliferation (CCP) in the normal mucosa of patients with left-sided colorectal carcinoma. Meat consumption was assessed by food frequency questionnaire, and CCP was determined in rectal biopsies obtained prior to surgery. K-ras mutations in the resected tumours were determined using a PCR-based oligonucleotide hybridization assay. Fifteen K-ras mutations were detected in tumours from 43 patients; 13/15 in codon 12, 3/15 in codon 13, and 1/15 in both codons 12 and 13. All mutations were G-->A or G-->T transitions. There was no statistically significant difference between intakes of red meat in patients with a K-ras mutation (92.4 +/- 9.7 g/day) and those without (82.3 +/- 7.7 g/day). Rectal CCP was significantly higher in patients than in healthy controls, but there was no correlation with meat consumption or K-ras mutation. These data do not support the hypothesis that meat consumption is a risk factor for acquisition of K-ras mutations during colorectal carcinogenesis.

A STUDY OF MULTIPLE PRIMARY CANCER ASSOCIATED WITH COLORECTAL CARCINOMA

In a recent 9-year period from January 1989 to December 1997, a series of 407 patients with colorectal carcinoma were operated on at the hospital, and 38 (9.3%) patients of them had cancers of the other organs. Clinicopathological study was carried out between patients groups with and without cancers of other organs. There was no significant difference in the clinicopathological features between two groups. Gastric carcinoma was the most common among cancers of other organs. In females, uterus cancer and breast cancer were seen often, which were accompanied by the left-sided colorectal carcinoma. There were 13 cases of synchronous and 25 cases of metachronous double cancer, including 22 cases in which colorectal cancer was preceded by other organ cancer. Rectal carcinoma was most frequently seen in regard to location of colorectal carcinoma. Operative results were satisfactory as long as each cancer was successfully resected. Double cancer has been increasing in patients with cancer after detection of the first cancer, and hence the possible association of third or forth neoplasm can be thought. It is especially important to pay attention to association of left-sided colorectal cancer in female patients after operation for uterus or breast cancer.

No difference in stem cell somatic mutation between the background mucosa of right- and left-sided sporadic colorectal carcinomas.

Epidemiological, morphological, and molecular differences exist between carcinomas of the right and left sides of the large bowel. To investigate whether this is reflected in differences in somatic mutation frequency in the background mucosa, mutation of the neutral O-acetyltransferase gene (oat) was quantified in histologically normal resection margins from 20 informative (heterozygous) patients with caecal or ascending colon cancer (11 males, median age 75 years) and 20 with sigmoid colon or rectal cancer (10 males, median age 70 years). Mutant discordant crypts lacking O-acetyltransferase activity were visualized by mPAS staining and classified as wholly or partially involved by the mutant phenotype; median frequencies (x10(-4) were compared (Mann-Whitney U-test) after assessing a sample of more than 10,000 crypts per case. No significant difference was found between the frequencies of wholly involved mPAS-positive crypts in background mucosa of left- and right-sided cancers (p = 0.4569), indicating that tumours on both sides of the colon are associated with similar levels of lifetime-accumulated stem cell mutational load. However, partially involved mPAS-positive crypts were significantly more frequent in mucosa from left-sided cancers (p < 0.04), indicating increased mutational activity during the previous 12 months. Analysis of mucosa proximal and distal to left-sided cancers showed that this increase was due to a statistically higher frequency of partially involved crypts in proximal mucosa, which probably resulted from the obstructive effects of the tumour causing increased exposure of the proximal mucosa to luminal carcinogens and/or epithelial regeneration in response to low-grade inflammation or ischaemia. The findings indicate that although left-sided colonic cancer is commoner than right-sided cancer in the British population, carcinomas on both sides of the large bowel arise in a background of similar levels of stem cell mutational activity.

The advantage of primary resection and anastomosis with intraoperative bowel irrigation for obstructing left-sided colorectal carcinoma.

Of a total 712 patients with left-sided colorectal cancer, 79 (11%) required emergency surgery due to severe obstruction by tumors. Of these 79 patients, 55 underwent tumor resection and anastomosis. Primary resection and anastomosis with intraoperative bowel irrigation was performed in 44 patients (primary group), while staged resection and anastomosis was performed in only 11 (staged group). In comparing the two groups, there was no significant difference in the rates of curative resection, being 76% versus 90%. However, the primary group demonstrated significantly lower rates of postoperative wound infection (P < 0.001), anastomotic dehiscence (P not equal to 0.05), and postoperative mortality, at 2% versus 18% (P < 0.05). The cumulative survival curve was also better in the primary group (P < 0.05). These favorable results of the primary group were confirmed by analyses which established that no bias of therapeutic backgrounds existed in either of the two groups. Thus, it was concluded that for left-sided obstructing colorectal carcinoma, intraoperative bowel irrigation, followed by primary resection and anastomosis, produces more advantageous results.