放大肠镜在结直肠肿瘤样病变诊断治疗中的应用价值

目的 探讨应用放大肠镜诊断结直肠肿瘤样病变及指导治疗的价值。方法 用放大肠镜对61例结直肠肿瘤患者的78个病灶进行了染色后的放大观察，按工藤分型进行了腺管开口类型诊断；同步进行镜下摘除或手术切除后，将放大肠镜诊断结果与组织病理诊断结果相比较，分析其一致性。结果（1）依据放大肠镜所见，诊断腺瘤等肿瘤性病变，总体符合率为96.2％，敏感性98.4％，特异性85.7％；（2）依据放大肠镜的诊断，对70个（89.7％）良性病变进行了同步微创治疗；（3）结合放大观察的肠镜检查，为决定其他8个病灶的治疗方案提供了重要依据。结论 放大电子肠镜诊断结直肠肿瘤样病变及时、准确，利用它可以同步完成病变的微创治疗。     

Pre-operative or postoperative colonic examination for synchronous lesions in colorectal cancer

A review of 130 consecutive large bowel examinations at which a cancer of the colon or rectum was diagnosed has been undertaken. Of 50 patients examined by colonoscopy, the whole colon was seen in only 21 (42 per cent) and almost half of these had a tumour in the caecum or ascending colon. In most cases, an incomplete examination was the result of narrowing of the lumen by the tumour preventing passage of the endoscope. Of 80 patients examined by double contrast barium enema, the entire length of the colon was visualized in 83 per cent but the quality of the examination was sufficient to confidently exclude synchronous neoplastic lesions in only 51 per cent. The incidence of synchronous cancer in this series was within the expected range, although two such cancers were not detected until laparotomy, but the incidence of synchronous adenomas was two-thirds of the expected number in colonoscopy patients and one-third in those examined by barium enema. It is concluded that, in patients with known colorectal cancer, preoperative investigation is unreliable for the detection of all synchronous neoplasia and that patients should have postoperative colonoscopy.     

Intraoperative colonoscopy in patients with colorectal cancer.

Sixty-seven patients underwent intraoperative colonoscopy during elective surgery for colorectal cancer. Complete examination of the colon was achieved in 65 patients (97 per cent), albeit with insertion through a colotomy in three (4 per cent). A synchronous carcinoma was found in six patients (9 per cent), which necessitated a change of planned surgical procedure. Synchronous polyps were detected and removed in 24 patients (36 per cent); two had polyps with carcinoma in situ. The mean age of patients with synchronous carcinoma was significantly higher than that of those without (74.1 versus 61.2 years, P = 0.02). Intraoperative colonoscopy took a mean of 15 min surgical time and only two minor complications (serosal lacerations) were encountered. In patients with colorectal cancer, intraoperative colonoscopy allows complete assessment of the colon and identifies synchronous lesions.     

Large hyperplastic polyps of the colon

Hyperplastic polyps are the most frequent nonneoplastic lesions of the colon. Typically, they are small sessile polyps (5 mm) located in the rectosigmoid area. Recently, they have been identified as markers of neoplastic polyps. Herein we describe four cases of large (20 mm in size) hyperplastic polyps found at our institution over a 9-year period. All four polyps were excised by endoscopic polypectomy on an outpatient basis without complications. Two polyps were in the right colon; one was pedunculated, none of them was associated with synchronous neoplastic polyps or polyposis. Up to now, follow-up in three patients has been negative for metachronous polyps. We conclude that a large hyperplastic polyp is an unexpected and rare finding, difficult to distinguish, and not related to particular colonic sites or synchronous adenomatous lesions. These polyps should be removed with a standard technique, and patients need to be followed with successive endoscopies.     

Use of computed tomography colonography to detect a synchronous early colorectal cancer in a patient with obstructive colorectal tumour

In patients with obstructive colorectal cancer, it is difficult to evaluate the oral site of the large bowel by colonoscopy. Instead of colonoscopy, previous studies have shown that computed tomography (CT) colonography is effective for detection of neoplastic lesions in the large bowel. In the present case, we carried out CT colonography and found superficial early cancer at the oral side of the obstructive cancer, and carried out surgical resection for both lesions. A 60‐year‐old man was admitted with complaints of abdominal pain and distension. Total colonoscopy could not be carried out because of the stricture of the lesion. To evaluate the proximal site of the large bowel, we carried out CT colonography, which showed a superficial lesion in the transverse colon suggestive of early cancer. He underwent surgery and an intraoperative colonoscopy of the transverse colon, which confirmed the findings of the CT colonography. The patient underwent R0 resection for both an advanced lesion and a superficial lesion. Pathological examination of the superficial lesion showed adenocarcinoma‐invading submucosa. The postoperative course was uneventful and the patient was discharged a week after the operation. The present case suggests the importance of CT colonography for patients with obstructive colorectal cancers to detect synchronous neoplastic lesions, including superficial early cancers.     

Effect of preoperative colonoscopy on the incidence of synchronous and metachronous neoplasms

Colonoscopy and air-contrast barium enema performed preoperatively in 389 patients with colorectal cancer revealed synchronous cancer in 4% and polyp in 14%. Nine of the 16 synchronous cancers were located in other surgical segments than the index cancer, and six of the nine were in stage A or B1. Of the 54 synchronous polyps, 28 were located in such other segments. Half of the synchronous cancers and almost half of the synchronous polyps were missed at double-contrast barium enema. All synchronous cancers and three-fourths of the synchronous polyps were detected at colonoscopy. No patient with preoperative colonoscopy presented with metachronous cancer within 3 years from surgery, and only two were subsequently found to have adenocarcinoma arising from an adenomatous polyp. Endoscopic polypectomy was performed in 21 cases during follow-up. Extensive use of preoperative colonoscopy is recommended in the evaluation of colorectal cancer, in order to promote detection of synchronous tumors, reduce the incidence of 'early metachronous' cancer and avoid malignant degeneration of adenomatous polyp.     

The effect of preoperative endoscopy on recurrence and survival following surgery for colorectal carcinoma

Numerous studies have elucidated the benefits of endoscopy before surgery for carcinoma of the colon and rectum. In patients with known colon cancer, the incidence of synchronous colon cancers is 1.5 to 7.6 per cent and synchronous colon polyps is 25 to 40 per cent. Standard barium contrast studies are inferior to endoscopic examination in detecting these synchronous lesions. Endoscopy has been shown to alter the planned surgical procedure in 11 to 13 per cent of patients with colorectal cancer. Nevertheless, some authors avoid preoperative endoscopy because of concern that neoplastic cells may be seeded throughout the colon during the examination. They fear that manipulation of the tumor may promote hematogenous or lymphatic spread. Our study seeks to demonstrate whether this concern is valid by comparing rates of local recurrence, distant metastases, and survival between patients who have undergone preoperative endoscopy with those who have not.     

The changed histologic paradigm of colorectal polyps

Background: Previous literature has recorded the preponderance of hyperplastic over neoplastic polyps. This study evaluated the histopathologic characteristics of colonic polyps, excised during colonoscopic polypectomy, and further determined their relationship to age, location, and gender. Methods: Of 5132 colonoscopies reviewed between 1976 and 1999, 757 were performed on 582 patients who had polyp removal. Patients with previous colon resection or incomplete cecal intubation were excluded. Results: The mean age was 67 ± 11 years for men and 66 ± 11 years for women. Of the 1050 lesions histologically analyzed, 871 (83.0%) were neoplastic, 129 (12.3%) were hyperplastic, and 50 (4.8%) were miscellaneous lesions (29 inflammatory polyps, 14 lipomas, 2 leiomyomas, 1 juvenile polyp, and 4 no pathology identified). Hyperplastic polyps were always less than 1 cm (with one exception) and were located predominantly in the left colon, the majority residing in the sigmoid colon. Peak prevalence of hyperplastic polyps occurred in the 50–70 years old age group. Of the neoplastic polyps, 566 (65.0%) were tubular, 225 (25.8%) villotubular, 63 (7.2%) villous adenomas, 4 (0.5%) mixed adenomatous hyperplastic polyps, and 12 (1.4%) invasive carcinomas. The peak prevalence of neoplastic polyps occurred in the same age group as did hyperplastic polyps. Even though adenomatous polyps outnumbered hyperplastic polyps throughout the colon and within each age group, a greater percentage of hyperplastic polyps were found distally and in younger patients compared to location and age groups for neoplastic polyps. Conclusion: Adenomatous polyps outnumber hyperplastic polyps 7:1, even in the distal colon. Even small polyps seen during colonoscopy should be removed and subjected to histologic analysis because of the advisability of follow-up examinations of patients with neoplastic polyps. The increase in the incidence of neoplastic polyps beginning at the age of 50 years supports the need for colonoscopy in these individuals.     

Minimally invasive treatment of synchronous colorectal tumours

In patients with colorectal cancers synchronous neoplastic lesions are an increasingly frequent finding at preoperative staging; 3% of the cases are other cancers while 33-35% of the synchronous lesions are villous adenomas. The treatment of most colorectal adenomas can be performed by endoscopic poplypectomy. In 5% of cases there are synchronous colorectal lesions also requiring surgical treatment. From January 1995 to June 2007 we treated 5 patients with rectal lesions by transanal endoscopic microsurgery (TEM) together with a laparoscopic colectomy for the presence of synchronous lesions at the "Clinica Chirurgica Generale e d'Urgenza" of the University of Perugia,. Surgical timing involved performing a sequential exeresis characterised by a cancer resection, followed by resection of the voluminous adenoma: TEM for rectal cancer followed by a laparoscopic right hemicolectomy with an extracorporeal anastomosis for a voluminous villous adenoma (1 patient) and laparoscopic right hemicolectomy with an extracorporeal anastomosis for cancer followed by TEM for a voluminous villous adenoma (2 patients). One patient with left colon cancer associated with a voluminous villous rectal adenoma first underwent TEM for the rectal adenoma and then a left laparoscopic hemicolectomy with an extracorporeal anastomosis in order to ease the transit of the circular mechanical stapler. Another patient with rectal and right colon adenomas first underwent TEM for a voluminous rectal sessile adenoma and later a right hemicolectomy. The use of this minimally invasive approach allowed rectum preservation and less invasive surgery.     

Colonoscopy after curative resection of colorectal cancer

Colonoscopy is generally considered to be an important part of the follow-up program for patients who have undergone curative resection of colorectal cancer. However, there are few data available concerning the frequency with which colonoscopy should be performed and for what length of time after operation. Since 1978, our policy has been to examine the colon annually in these patients using colonoscopy alternating with barium enema. We have evaluated the results in 100 patients over a four-year period. Based on size and histology, the significant colonoscopic findings were new colon cancers in three patients and 11 polyps demonstrating increased risk for malignancy in nine patients. This represents an interval yield of 3% per year. From these results and other reports, we recommend that these patients undergo total colonoscopy in the perioperative period to identify and remove synchronous lesions of the colon, and that examination of the remaining colon should be performed annually, preferably with colonoscopy, for at least the first four years after curative resection.     

双镜联合治疗复杂性结肠息肉30例临床分析

目的探讨电子结肠镜联合腹腔镜手术治疗复杂结肠息肉的可行性与安全性。方法回顾性分析30例基底直径≥2．0cm,位置特殊,无法内镜下摘除的结肠息肉,在电子结肠镜辅助下行腹腔镜手术治疗的近期疗效。结果30例均在双镜联合下顺利完成手术,其中肠镜辅助腹腔镜下部分肠壁切除19例,腹腔镜下肠段切除6例,双镜联合小切口辅助部分肠切除3例,术中病理证实为恶性者行腹腔镜结肠癌根治术2例。手术时间50～185min,平均（79．6±28．6）min;术后无吻合口漏和吻合口梗阻发生;有1例患者出现吻合口出血,经保守治疗痊愈。术后肠功能恢复时间1～4d,平均（2-3±2．7）d;住院时间3～12d,平均（5．0±2．0）d。术后随访6—15个月,平均（9．8±2．7）个月;除6例失随访外,24例复查肠镜未见息肉残留、复发。结论腹腔镜联合电子结肠镜不仅定位准确,对恶性患者更改切除术式灵活,而且术后并发症发生率较低,是一种治疗复杂结肠良恶性息肉安全、有效的方法。     

Patient management after endoscopic removal of the cancerous colon adenoma.

The subject of management of patients after endoscopic removal of cancerous adenomas is controversial. A retrospective review of 126 lesions in 121 patients who had had colonoscopic polypectomy of malignant lesions between 1971 and 1985 was used to determine the criteria for colon resection. Invasive cancer was identified in 80 patients, while 41 patients had carcinoma in situ. A synchronous colon cancer was found in five of the 121 patients. The patients who had carcinoma in situ had no evidence of residual tumor or metastatic disease on subsequent follow-up (colon resection in three patients and endoscopic surveillance in 38 patients). Of the 80 patients with invasive cancer, 44 had subsequent colon resection, and 34 of these had no evidence of tumor in the resected bowel or mesenteric lymph nodes. Ten patients had residual tumor, metastatic cancer to regional lymph nodes, or both. Each of the 10 had at least one of the following indications of inadequate resection or dissemination of disease to local lymph nodes (the first indication is a macroscopic evaluation, while the remaining four are all microscopic): incomplete excision, poorly differentiated tumor, invasion of the line of resection, invasion of the polyp stalk, and invasion of venous or lymphatic channels. Present recommendations for patient management after endoscopic removal of an invasive malignant adenoma should include colon resection with regional lymphadenectomy for patients with one or more of these five criteria. Patients without any of these risk factors should have early repeat endoscopic examination 3 months after initial polypectomy to evaluate the polypectomy site. Total colonoscopic examination is repeated at 1 year to ensure the surveillance program is begun with a colon without neoplasms.     

A prospective analysis of extended endoscopic mucosal resection for large rectal villous adenomas: an alternative technique to transanal endoscopic microsurgery

INTRODUCTION: Endoscopic mucosal resection is a safe resection tool for selected flat, sessile and lateral spreading tumours of the colon. Transanal microsurgical resection of select rectal neoplastic lesions is another accepted modality. Recent data suggests transanal microsurgery may have high complication rates. We conducted a prospective clinicopathological evaluation of an extended endoscopic mucosal resection technique for highly selected lesions of the rectum and assessed outcome data over a maximal 24-month period. PATIENTS AND METHODS: Eighty-three patients with known rectal neoplastic lesions underwent chromoscopic colonoscopy and on-table staging using a high-frequency (12.5 MHz) mini-probe EUS by a single endoscopist. Patients with T2 or node positive disease were referred for surgery. Following extended endoscopic mucosal resection patients were followed-up at 3, 6, 12 and 24 months post 'index' resection with chromoscopic endoscopy and EUS. Procedural complications, recurrence rates and outcome data were collected. RESULTS: Sixty-two patients fulfilled inclusion criteria. Median procedure time was 48 mins (range 32-126). Lateral spreading tumours (median diameter 30 mm; range 18-42 mm) and sessile lesions (median diameter 38 mm; range 25-86 mm) accounted for 19% and 81% of lesions, respectively. Ninety-seven percent of patients undergoing EMR were discharged within 6-h of procedure. Thirty-day re-admission and death rate was 0%. Bleeding complications occurred in 5/62 (8%) of patients with all achieving complete haemostasis using endo clips. None required transfusion. There were no procedural related complications or perforations. Overall 'cure' rate at a median follow-up of 16 months was 98%. CONCLUSIONS: Extended endoscopic mucosal resection for rectal neoplastic lesions can achieve superior results to those of per-anal excision and trans-anal microsurgery with regard to complications and recurrence rates. Extended endoscopic mucosal resection may be an alternative therapeutic modality in selected patients.     

Ultrasound of colonic neoplasia

BACKGROUND: The accuracy of intraoperative ultrasound of the colon in the location and assessment of neoplastic lesions at the time of resection has not been reported. METHODS: An in vitro study was performed, with ultrasound imaging of colonic specimens resected for malignancy. The specimens were imaged empty, surrounded by saline, the lumen filled with saline. RESULTS: Excellent ultrasound images were produced, particularly when the colonic lumen was filled with saline. All lesions were located by this technique, and several impalpable synchronous polyps also were found. In two specimens, the remnants of a malignant polyp not visible with intraoperative colonoscopy were found by specimen ultrasound. The clarity of the image was such that the cancer stage often could be assessed. CONCLUSIONS: Direct ultrasound of the colon, using a high-frequency intraoperative probe, produced accurate images of neoplastic lesions in an in vitro setting. This technique may have a role in the intraoperative location and assessment of colorectal cancer.     

Synchronous carcinoma of the colon and rectum: prognostic and therapeutic implications

In a series of 1,037 patients with colorectal carcinoma diagnosed at one hospital during a 9-year period, synchronous cancers of the colon and rectum occurred in 2 percent. Patient characteristics and presenting symptoms were similar in single and synchronous carcinomas. The frequency of patients with associated benign neoplasms was significantly higher than that in the parent series. An examination of the modified Dukes' classification stage of the lesion in each patient revealed a higher incidence of lymph node involvement and a greater frequency of mucinous adenocarcinoma in patients with synchronous carcinomas. The 5-year survival of patients with synchronous growths did not differ from that of patients with single lesions, even when classified by Dukes' stage. Preoperative diagnosis was difficult, being achieved in no more than 30 percent of patients. Because of the poor accuracy of barium studies, total colonoscopy is the method of choice for this evaluation. We adopted a conservative surgical policy backed by life-long follow-up.     

The elusive colonic malignancy. A need for definitive preoperative localization

Colonoscopy with biopsy is the standard of practice for the diagnosis of colonic malignancies. Unfortunately, the inability of endoscopy to obtain precise distance measurements from the anal verge can make localization of lesions at operation difficult. For this reason, preoperative barium enema or intraoperative colonoscopy have been advocated to further pinpoint the sites of those lesions not thought to be easily located at operation. Five patients are presented in whom malignant lesions of the colon were diagnosed and verified histologically, but were later undetectable at operation or subsequent colonoscopic examinations. Four of these patients underwent laparotomy and three received colon resections. None of these patients' tumors were identified during intraoperative colonoscopy, in the resected bowel on pathologic examination, or on follow-up colonoscopy. A fifth patient is presented who spontaneously passed a polyp containing invasive adenocarcinoma, but multiple colonoscopic examinations have failed to identify the site of the lesion. To date, none of these tumors have recurred with periods of follow-up ranging from 6 months to 2 years. These patients demonstrate a poorly documented and little understood aspect of the behavior of colonic malignancies, i.e., the ability to spontaneously regress or slough from the bowel wall. Based on these instances, localization of potentially malignant colon lesions is recommended with submucosal dye injections at initial endoscopy or with colonoscopy in the operating room immediately prior to operation.     

Increased incidence of colorectal adenomas in follow-up evaluation of patients with newly diagnosed hyperplastic polyps

Background: Although adenomatous polyps have been established clearly as precursor lesions for most cases of colorectal cancer, the role, if any, of hyperplastic polyps remains uncertain. The aim of the current study was to determine whether a patient with an index finding of hyperplastic polyp on colonoscopy is at increased risk for adenomatous polyps. Methods: We conducted a retrospective cohort study using the records of a single surgeon's colonoscopic experience over a 20-year period (June 1973 to December 1994). Patients found to have hyperplastic lesions on index colonoscopy were compared with those who had "clean" index colonoscopies. The two groups were compared for the subsequent diagnosis of adenomatous polyps on follow-up colonoscopies. Those with cancer or adenomas at index colonoscopy or in their history were excluded. We used Cox proportional hazard modeling with subsequent adenoma or cancer diagnosis at follow-up colonoscopy as the outcome, controlling for age and gender. Results: We identified 42 patients for whom hyperplastic polyps were the only colorectal neoplasms found on the index examination, in contrast to 362 control patients who had a "clean" index examination. In this cohort study, patients found to have only hyperplastic polyps on initial examination had a rate of subsequent adenoma diagnoses (42%) twice that of patients with a clean initial colonoscopy (21%). Mean follow-up time was 4.3 years. The relative rate ratio was 2.0 (95% confidence interval, 1.2-3.4). Conclusions: This study suggests that patients found to have hyperplastic polyps on initial colonoscopic examination may have twice the risk of adenomas on follow-up colonoscopy, as compared with those who have clean initial examinations. If this finding is borne out in larger prospective studies, surveillance strategies may need to be modified accordingly. apd: 14 May 2001     

Advanced proximal colon cancer

BACKGROUND: Two recent studies have documented that sigmoidoscopy as a screening tool for colorectal cancers may miss advanced proximal colonic neoplasms. The purpose of this study was to assess the prevalence of distal synchronous lesions in patients with proximal colon cancer. We sought to determine if screening sigmoidoscopy would have missed these proximal colon cancers. METHODS: Data were collected on all patients (n = 305) diagnosed with colorectal cancer over a 6-year period. Patients were stratified by age, sex, tumor location, presenting complaint, AJCC stage, and TNM classification. The colonoscopy results of patients diagnosed with proximal colon cancer were analyzed to determine the incidence of synchronous distal colon lesions. RESULTS: Proximal colon cancer was diagnosed in 88 patients (29%). Of those studied, 45 (54%) did not have synchronous distal lesions detected by colonoscopy. The patients with proximal colon cancer were elderly (mean age 67), had advanced tumor size [59 patients (67%) T3/T4], and had advanced AJCC stages [37 patients (42%) stage III/IV]. Nearly all patients [84 (95%)] with proximal colon cancer were symptomatic. CONCLUSION: In this study, the majority of patients with proximal colon cancer did not have a synchronous lesion in the distal colon. Current screening methods for colon cancer based on sigmoidoscopy would not have identified these proximal lesions. These findings support the incorporation of screening colonoscopy in protocols designed to identify early colon cancer.