Extent of prevalence and size of flat neoplasms in a heterogeneous population undergoing routine colorectal cancer screening

Background The importance of identifying flat colorectal neoplasms is increasingly appreciated, although the extent of prevalence of these lesions in a general population is not known. Objective To determine the extent of prevalence of flat neoplasms in a diverse population undergoing routine endoscopic screening for colorectal cancer. Design Patients referred to the Colorectal Cancer Screening Clinic over a 12‐month period (n = 642). Results The patient population was 56% African American and 21% Caucasian; with a mean age of 59 ± 9 years. Flat neoplasms were detected in 5.5% of all patients, similar to that reported elsewhere, with extent of prevalence being similar regardless of gender or race. Average size of flat neoplasms was of 2.8 ± 2.3 mm (range 1–20 mm). However, there was no evidence of advanced pathology in any of the flat neoplasms identified. Conclusions Flat neoplasms are common but may not be associated with advanced pathology in a population undergoing routine screening.     

腹腔镜外科技术在结直肠恶性肿瘤切除术中的应用

目的探讨腹腔镜在结直肠恶性肿瘤切除手术中的应用. 方法经腹腔镜施行结直肠恶性肿瘤切除术17例,其中行右半结肠根治性切除术3例,乙状结肠根治性切除3例,直肠癌行Dixon术7例、Mile术2例、Park术2例.采用完全腹腔镜手术6例,腹腔镜辅助手术8例,手助腹腔镜手术3例. 结果全部病例均治愈出院,无死亡病例,无并发症发生,无中转开腹病例,手术时间150～240 min,平均190 min,术中出血20～300 ml,平均55 ml,术后平均住院9.6 d,有6例使用镇痛剂,术后近期随访1～6个月无复发. 结论经腹腔镜结直肠恶性肿瘤切除术是安全可行的,近期效果满意.     

Initial experience with a general population colorectal cancer screening clinic

BACKGROUND: Recognition of adenoma to carcinoma progression has established colorectal cancer as a preventable malignancy. Colorectal cancer is, therefore, an ideal malignancy for preventative screening given the presence of a benign precursor. We set out to establish a pilot low-risk endoscopic screening clinic and we discuss our initial results. METHODS: A retrospective chart review of all patients referred to a new low-risk colorectal cancer endoscopic screening clinic from October 1, 2004 to September 30, 2005 was performed. Those patients found to have adenomas or carcinomas were analyzed further regarding location of neoplasm and pathologic findings. RESULTS: A total of 379 low-risk patients attended the colorectal cancer screening clinics. The age range of the patients was 50 to 86 years. The male to female ratio was 254 to 128. A total of 257 patients had flexible sigmoidoscopy as the initial screen, 24 patients had partial colonoscopy, and 98 patients had complete initial colonoscopy. A total of 152 patients had polyps removed, of which 63 patients had adenomas, 3 had adenocarcinomas, 1 had a carcinoid, and the remaining had an assortment of nonneoplastic polyps. Of the 67 patients with neoplasms, 50 were left of the splenic flexure, 11 were right of the splenic flexure, and 5 patients had lesions both proximal and distal to the flexure. Thirty-two of the 67 patients had complete colonoscopy at the initial procedure and, thus far, 21 patients have had completion colonoscopies, of which 9 patients had further neoplasms identified beyond the splenic flexure. All 3 patients with carcinoma had early tumors resected with curative intent, with negative margins and negative nodes. CONCLUSIONS: Our initial experience with a low-risk general population colorectal cancer endoscopic screening clinic yielded 18% of patients with neoplasms, and 1% had curable cancers resected.     

腹腔镜下结直肠癌根治术的临床应用研究

目的:探讨腹腔镜结直肠癌根治术的临床应用价值。方法:回顾分析77例腹腔镜下结直肠癌根治术的临床病例资料,其中右半结肠切除术12例、横结肠切除术2例、左半结肠切除术12例、乙状结肠切除术8例、直肠癌行直肠前切除术19例、直肠癌行结肠拖出式切除术8例、Miles术12例、结肠次全切除术2例、全结肠切除术2例。结果:75例均在腹腔镜下完成,腹腔镜手术切除率97.4%(75/77),2例中转开腹行Miles术;手术时间平均175min;术中出血量平均110ml;术后肠蠕动恢复时间平均1.9d;术后无出血、吻合口漏、伤口感染等并发症,4例出现轻度尿潴留症状,6例术后轻度性功能障碍;术后平均住院7.5d;术后随访2~42m;死亡2人。结论:运用腹腔镜技术进行结直肠癌根治术,具有操作安全、创伤小、恢复快等特点,不仅技术上可行,而且完全可达到开腹根治术的效果。     

Invasive colorectal cancer within 5 years of negative colonoscopy in a Japanese population

Aim Colonoscopy provides imperfect protection against colorectal cancer (CRC). In an attempt to improve cancer detection we evaluated the clinical features of invasive CRC detected within 5 years of a negative colonoscopy. Method The details of colonoscopies performed in a rural hospital in Japan were prospectively recorded at the time of the examination. The patients were followed over 5 years for the subsequent occurrence of cancer. Results In a 5‐year period, 10 148 patients underwent colonoscopy and 202 without previous colonoscopy were diagnosed with invasive CRC. Of 3212 patients with a colonoscopy negative for cancer, nine developed invasive cancer within 5 years. The ratios for invasive CRC detected without/with previous colonoscopy were 60:1 in the rectum, 54:1 in the sigmoid colon, 15:1 in the descending colon, 28:0 in the transverse colon, 31:5 in the ascending colon and 14:1 in the caecum (P = 0.041). The ratio between left‐ and right‐sided colonic cancer was also significantly different (129:3 and 45:6, P = 0.0078). Six (67%) of the invasive CRCs were in the ascending colon or caecum. Five of six patients with invasive CRC in the ascending colon and caecum had right‐sided small adenomas at prior colonoscopy. Conclusion The majority of early/missed CRCs were right‐sided and associated with prior right‐sided colonic adenomas. Repeated colonoscopy of patients with right‐sided adenomas at a shorter surveillance interval deserves consideration.     

Carcinoembryonic antigen to detect hepatic metastases of colorectal cancers

Purpose. The spread of colorectal carcinoma (CRC) affects both staging and treatment. In this prospective study we examined the relationship between carcinoembryonic antigen (CEA) levels in bile, mesenteric venous blood, and peripheral venous blood, and the presence of occult hepatic metastases in patients with CRC.Methods. Sixty patients who underwent elective surgery at Ankara Oncology Hospital were voluntarily assigned to one of the three groups of 20 patients each. The control group consisted of patients operated on for benign biliary disorders, the second group consisted of patients with CRC without metastases, and the third group consisted of patients with CRC and isolated liver metastases. Bile, mesenteric venous blood, and peripheral venous blood was collected perioperatively for the measurement of CEA levels.Results. The bile CEA levels were significantly higher in the CRC patients with metastases than in those without metastases and the controls. The CEA levels in the mesenteric venous blood and peripheral venous blood were significantly higher in the two groups of CRC patients than in the control group. Overt hepatic metastases later developed in seven patients from the CRC without metastases group who had relatively high CEA levels, but the difference was not significant.Conclusion. The CEA levels in bile, mesenteric venous blood, and peripheral venous blood were increased in patients with CRC and liver metastases. The detection of elevated CEA levels in bile taken at surgery did not herald metachronous hepatic metastases in CRC patients without liver metastases.     

Observations of aggressive,small, flat,and depressed colon cancer

Three cases of small, flat, and depressed colon cancers are reported. One lesion is less than 1 cm in diameter with lymphatic invasion in the submucosa; the other measures 0.8 cm in the longest dimension and penetrates through the muscular layers to the subserosa. The third one, 1.2 cm in diameter, has had liver metastasis. The endoscopic appearances of two lesions with a resected specimen are presented in color to demonstrate some difficulties in visualizing these lesions for endoscopists. The biologic aggressiveness of these three lesions appears due to their rapid growth, which is expressed by a high mitotic rate of the cancer cells. Their histogenesis is considered to derive from (1) flat adenoma, from (2) serrated adenoma, and (3) from hyperplastic epithelium (or de novo in origin), respectively.     

Small, flat colorectal cancers in the UK population: an analysis of resected specimens

OBJECTIVES: To establish the prevalence of small, flat carcinomas in surgically resected colon. To determine whether tumour morphology influences stage at presentation. METHOD: 1763 surgically resected colorectal cancers from one UK centre excised between 1995 and 2004 were examined. Age 69 years, (42-90), M:F equal. Sixty-one tumours < or =20 mm across were identified. Slides were reviewed by a consultant histopathologist and classified using Japanese Research Society Classification, JRSC and TNM staging. Fisher's exact test was used for analysis. RESULTS: In 61 small cancers, 64% (39/61) showed flat morphology and 33% (20/61) polypoid. Two lesions were unclassifiable. Prevalence was 2.2% of all resected colorectal cancers. More T1 tumours at presentation were polypoid, (30% vs. 8%; P = 0.033). T3 tumours were more likely to be flat than polypoid, (49% vs. 20%; P = 0.016). Infiltration into musclaris mucosa occurred in 77% (30/39) flat tumours. Rates of metastases were high in both groups, (30% polypoid vs. 39% flat, not significant). CONCLUSIONS: The prevalence of small, flat cancers in resected specimens in the UK concurs with that of Japanese studies. Small, flat cancers should be staged carefully because of high rates of T3/4 disease. The results support the theory of accelerated carcinogenesis in flat cancers.     

Thirty-day mortality from colorectal cancer surgery within a deprived population

OBJECTIVE: A recently published model for predicting 30-day mortality has been devised using data from 73 hospitals in the UK. Deprivation category was not one of the data sets used in predicting mortality and was not included in formulating this model. We wished to assess if the model was applicable to a population with high deprivation category scores. METHODS: Data on all colorectal cancer operations included in the model (age, ASA, cancer resected, Dukes stage and urgency) had been collected prospectively since January 1999. This data was applied to the model. RESULTS: Two hundred and thirty patients were included in analysis. Overall predicted mortality was 8.2% and actual mortality 7.8%. Within different categories of deprivation, predicted and actual mortality are similar and not significantly different. 137 patients lived in areas of deprivation category 3-5. Predicted and actual mortality were 8.4% and 8.0%, respectively. In areas of deprivation category 6-7, 91 patients had a predicted and actual mortality of 8.0% and 7.7%. CONCLUSION: Although deprivation data was not included in the production of the mathematical model to predict postoperative death, the model appears to predict well in the deprived population. It is likely that poorer socio-economic status is accounted for by increased ASA and cancer stage.     

Management of colorectal polyp cancers

INTRODUCTION

Management of malignant colorectal polyps is controversial. The options are resection or surveillance. Resection margin status is accepted as an independent predictor of adverse outcome. However, the rate of adverse outcome in polyps with a resection margin of <1mm has not been investigated.

METHODS

A retrospective search of the pathology database was undertaken. All polyp cancers were included. A single histopathologist reviewed all of the included polyp cancers. Polyps were divided into three groups: clear resection margin, involved resection margin and unknown resection margin. Polyps were also analysed for tumour grade, morphology, Haggitt/Kikuchi level and lymphovascular invasion. Adverse outcome was defined as residual tumour at the polypectomy site and/or lymph node metastases in the surgical group and local or distant recurrence in the surveillance group.

RESULTS

Sixty-five polyps (34 male patients, mean age: 73 years, range: 50–94 years) were included. Forty-six had clear polyp resection margins; none had any adverse outcomes. Sixteen patients had involved polyp resection margins and twelve of these underwent surgery: seven had residual tumour and two of these patients had lymph node metastases. Four underwent surveillance, of whom two developed local recurrence. Three patients had resection margins on which the histopathologist was unable to comment. All patients with a clear resection margin had no adverse outcome regardless of other predictive factors.

CONCLUSIONS

Polyp cancers with clear resection margins, even those with <1mm clearance, can be treated safely with surveillance in our experience. Polyp cancers with unknown or involved resection margins should be treated surgically.     

腹腔镜辅助结直肠癌根治术的临床应用

目的：探讨腹腔镜辅助结直肠癌根治术的可行性、安全性及近期疗效。方法：回顾分析2007年8月至2009年6月施行的32例腹腔镜辅助结直肠癌根治术的临床资料。其中右半结肠切除术5例,横结肠切除术1例,左半结肠切除术7例,乙状结肠切除术5例,结肠次全切除术1例,直肠癌行Dixon手术7例,Miles手术6例。结果：除2例中转开腹外,余30例均在腹腔镜辅助下顺利完成手术,无手术死亡病例;结肠癌切除包括肿块在内的12~23cm肠管;直肠癌行Dixon术或Miles术时,下端切缘距肿瘤下缘3~5cm,术后病理证实所有标本残端均无肿瘤细胞残留、浸润。手术时间130~248min,平均152min;术中出血90~320ml,平均160ml;术后肠蠕动恢复时间36~72h,平均48h;淋巴结清扫4~22枚,平均12.6枚。术后无出血、吻合口瘘和狭窄等并发症发生,术后仅1例切口感染,2个月后再次清创缝合后痊愈;术后住院5~9d,平均7.2d;术后电话随访至2010年2月,死亡1例,局部复发1例,余患者随访期内均未发现转移、复发及切口种植。结论：腹腔镜辅助结直肠癌手术具有患者创伤小、操作安全、术后康复快等优点,不仅技术上可行,而且完全可取得与传统开腹手术同样的治疗效果。     

Microsatellite and chromosomal stable colorectal cancers demonstrate poor immunogenicity and early disease recurrence

Objective  Colorectal cancers may demonstrate chromosomal instability (CSI) or microsatellite instability (MSI-H). A third group of microsatellite and chromosome stable (MACS) colorectal cancer has been described more recently. Patients with MSI-H colorectal cancers demonstrate improved outcome and a pronounced inflammatory infiltrate. Enhanced host immune response and increased immunogenicity might explain these observations. This study aims to further characterize colorectal cancer immunogenicity.
Method  Microsatellite stability status was determined in resected tumour samples. Microsatellite stable (MSS) tumour samples were stratified by DNA ploidy status, as determined by flow cytometry into aneuploid MSS (CSI) and diploid MSS (MACS) cancers. Lymphocyte proliferation, quantified by bromodeoxyuridine incorporation assays assessed tumour protein immunogenicity and ELISA assays quantified inflammatory cytokine release. Kaplan–Meier survival curves and multivariate analyses were used to determine prognostic value.
Results  Patients with MSI-H colorectal cancer had improved outcome but those with MACS cancers undergoing curative surgery had significantly poorer disease-free survival ( P  = 0.002). The MACS phenotype was an independent predictor of poor outcome (HR = 2.44, 1.33–4.47, P  = 0.004). Lymphocyte proliferation assays confirmed enhanced immunogenicity of MSI-H proteins and reduced immunogenicity of MACS proteins ( P  < 0.0001). In vitro levels of IFN-γ ( P  = 0.004) and IL-18 ( P  < 0.0001) mirrored these differences in lymphocyte activity.
Conclusions  Stratification of colorectal cancer by MSI and ploidy status may have prognostic value in patients undergoing curative surgery. MSI-H cancers display enhanced immunogenic properties but the immune response to MACS cancers appears to be absent and this may contribute to their poor prognosis.     

The influence of a colorectal service on the outcome of patients with colorectal cancer

Objective To perform a prospective audit of outcomes and survival of all patients presenting to a colorectal service with colorectal cancer, and to compare these results with an historical control group. Patients and methods At a community based teaching hospital, a prospective audit of outcomes and survival of patients with colorectal cancer was compared with a historical control. The study included all patients referred to a colorectal service with colorectal cancer from 1996 to 2000 (5‐year period). The control group was a retrospective review of patients presenting to the same hospital with colorectal cancer from 1989 to 1994 (6‐year period). A Kaplan‐Meier survival analysis compared the overall survival (all‐cause mortality) between the two groups. Results When comparing the study periods 1989–95 (n = 477) to 1996–2000 (n = 323), there has been a significant reduction in postoperative stay (16.2 vs 8.0 days, P < 0.05), and a reduction in postoperative mortality (4.5%vs 2.7%, n.s.). There was a significant increase in the overall 2 years survival for patients with colorectal cancer (62% to 71%, P < 0.01). There was also a significant increase in the overall 2 years survival of patients with rectal cancer (66% to 74%, P < 0.01), patients with ACPS C colon cancers (64% to 83%, P < 0.05), and ACPS C rectal cancers (74% to 85%, P < 0.01). Conclusions There have been significant gains in the survival of patients presenting to a community based teaching hospital with colorectal cancer. These improvements have been most notable in patients with nodal metastases at the time of diagnosis.     

Survival outcome of patients with screening versus symptomatically detected colorectal cancers

Aim The national Bowel Cancer Screening Programme has been rolled out nationwide following pilot screening in two health authorities in the UK. The aim of this study was to define overall 5‐year survival of screen detected cancers and to compare the overall survival outcome of screened vs symptomatic patients over a 10‐year period. Method All patients with colorectal cancer treated at one trust in patients of screening age (50–69 years) during the pilot screening programme (2000–2008) were analysed. Patients were defined as screen detected or symptomatically detected. Disease pathology and recurrence data were obtained from the hospital’s computerized results reporting system and mortality was cross‐matched with data from the West Midlands Cancer Intelligence Network. Results In all, 633 patients aged 50–69 were identified in the study period; 155 patients had a screen detected cancer and 478 did not. A log‐rank test completed on survival outcomes indicated that survival was significantly worse in the symptomatic group. This difference persisted if only patients treated with curative intent were considered. Conclusion Survival outcome was significantly better in the screened vs the symptomatic population in all groups and also in those treated for curative intent. There was a trend towards better survival for screen detected cancer when compared stage for stage.     

From small acorns--developing a laparoscopic colorectal surgical service

INTRODUCTION

Randomised controlled trials have shown that laparoscopic colorectal surgery is equal in terms of safety to open surgery. Benefits have been seen for length of stay, blood loss, immune suppression and analgesia requirements. The aim of this study was to assess the safety and feasibility of introducing laparoscopic colorectal surgery to our unit.

PATIENTS AND METHODS

Prospectively collected cases of all patients undergoing laparoscopic colorectal surgery between July 2003 and July 2007 were reviewed.

RESULTS

A total of 143 patients (75 males and 68 females) with amean age of 65.8 years (range, 21–95 years) underwent surgery. Laparoscopic resection for colorectal malignancy was performed in 93 patients (65%). The conversion rate for all cases was 14.7%. Mean operative time was 203 min (range, 100–400 min), with amean blood loss of 180 ml. The mean number of lymph nodes in malignant cases was 13.8 with clear resection margin in all but one case. The mean postoperative stay was 5.6 days (median, 4 days; range, 2–35 days). UKCCR standard for lymph node retrieval was achieved in 62.6% of cases. There were four postoperative deaths. The overall 30-day morbidity rate was 21.7%. The service is consultant-led with 9.8% of cases performed by senior trainees and 37% of procedures performed by two consultants.

CONCLUSIONS

Laparoscopic colorectal surgery is technically feasible and safe in our hands. Although operative time is longer, this is counterbalanced by shorter hospital stay. The results from this series support the findings of others and continuing development of this service.     

Antioxidants in the chemoprevention of colorectal cancer and colorectal adenomas in the general population: a systematic review and meta‐analysis

Aim Antioxidants, such as vitamin A, C and E, selenium and β‐carotene, have been proposed as possible agents in the chemoprevention of colorectal cancer and have been the subject of recent trials and reviews. This review aimed to assess the present evidence on the effect of antioxidants on the incidence of colorectal neoplasms in the general population. Method A systematic review of randomized controlled trials was undertaken comparing antioxidants alone or in combination with other agents vs placebo. The following databases were searched for published and unpublished literature: Cochrane Library, MEDLINE, PreMEDLINE, CINAHL, EMBASE, Web of Science, and Biological Abstracts and Research Registers. Studies were quality appraised and extracted. Meta‐analysis was performed. Results Twelve studies were identified as relevant. In the nine comparing antioxidants with no antioxidants (n = 148 922), there was no difference in the incidence of colorectal cancer [relative risk (RR) 1.00, 95% confidence interval (CI) 0.88–1.13]. One study assessed the effect of antioxidants on adenoma formation (n = 15 538) and did not demonstrate a statistically significant effect (RR 1.47, 95% CI 0.97–2.23). Of 14 discrete analyses for different combinations of antioxidants, only one reported a statistically significant increase in relative risk of adenoma formation in participants receiving vitamin E (RR 1.74, 95% CI 1.09–1.79, P = 0.02) or vitamin E plus β‐carotene (RR 1.63, 95% CI 1.01–2.63, P = 0.04). Effectiveness did not seem to differ between healthy populations, participants with cardiovascular risk factors or populations exposed to smoking or asbestos. Conclusion The review demonstrates that antioxidants (vitamin A, C and E, selenium and β‐carotene), as single agents, in combination with other antioxidants or in combination with other agents, are not effective in the chemoprevention of colorectal neoplasia in the general population. This questions their involvement in future randomized controlled trials of chemoprevention in colorectal cancer.     

Laparoscopic total colectomy for colorectal cancers: a comparative study

Background No previous report could be found in the literature comparing laparoscopic and open total colectomy for colorectal cancers, especially synchronous colorectal cancers. This study aimed to compare the short-term clinical outcomes and oncologic results of laparoscopic and open total colectomy or proctocolectomy for colorectal cancers. Methods Between July 1997 and January 2005, six patients with colorectal cancers underwent elective laparoscopic total colectomy or proctocolectomy at the authors’ institution. Clinical data for 12 patients who underwent elective open total colectomy or proctocolectomy for colorectal cancers during the same period were prospectively collected and compared. Results The median follow-up periods were 43.9 months for the laparoscopic group and 48.2 months for the open group. Conversion to open procedure was required for one patient (16.7%) in the laparoscopic group because of bleeding. The median operative time was significantly longer in the laparoscopic group (427.5 min; range, 280–480 min vs 172.5 min; range, 90–260 min; p = 0.001). The patients in the laparoscopic group required a significantly shorter duration of parenteral analgesia (3 vs 5 days; p = 0.01), but there were no differences in time to first bowel motion, time to resumption of diet, time to full ambulation, and duration of hospital stay between the two groups. Perioperative morbidity rates were comparable between the two groups, and there was no operative mortality. The oncologic results, including number of lymph nodes removed, recurrence rates, and survival rates, were similar in the two groups. Conclusions Laparoscopic total colectomy has short-term clinical outcomes (postoperative recovery and perioperative morbidity and mortality rates) and oncologic results similar to those of open surgery for treating patients with colorectal cancers. Our study has shown that the only advantage of laparoscopic over open surgery is a shorter duration of analgesic requirement, but at the expense of a longer operative time.     

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目的 研究遗传性非息肉病性大肠癌（ＨＮＰＣＣ）在大癌中的比例及临床病理特点。方法 收集和分析５５０例大肠癌的临床病理及随访资料，符合Ａｍｓｔｅｒｄａｍ标准或日本标准者诊断为ＨＮＰＣＣ。结果 ５５０例大肠癌中６例（１．１％）符合Ａｍｓｔｅｒｄａｍ标准，１９例（３．５％）符合日本标准。本组ＨＮＰＣＣ的临床病理特点是肿瘤发病年龄早，多位于右半结肠，粘液癌及多原发大肠癌多见，家族中肠外肿瘤增多，息肉伴随增     

结直肠癌根治术后单纯性肺转移60例临床病例分析

目的:结直肠癌患者根治术后大约有50%会发生远处转移,最常见的转移部位是肝,其次是肺,本文旨在探讨结直肠癌根治术后肺转移的特点、治疗效果和影响预后的因素.方法:随访1967年至2002年间的结直肠癌根治术后发生单纯性肺转移的60例病例,对其临床资料进行回顾性分析和总结.结果:自原发灶切除术后全组病例中位生存时间 37 个月,其中有15例行转移灶的切除手术,中位生存 51个月;其余 45例行非手术治疗,中位生存34 个月;转移瘤大于3个组生中位生存时间 30月,转移瘤小于等于3个组中位生存时间43个月.患者的总生存率可能和是否手术、转移灶的个数有关,而年龄、性别、原发灶病理类型、分期、转移灶大小对生存率无明显影响.结论:结直肠癌根治术后单纯性肺转移的积极治疗是有效的,手术及转移灶个数可能是影响治疗效果的因素.