Prognostic significance of CEA levels and positive cytology in peritoneal washings in patients with colorectal cancer

OBJECTIVE: The aims of this prospective study were to determine carcinoembryonic antigen (CEA) levels and incidence of cytology in peritoneal washings of patients with colorectal cancer, correlate the results with various histopathological factors and determine their significance as prognostic factors of the disease. METHODS: From 1992 to 1999, 98 patients with adenocarcinoma of the colon or intraperitoneal rectum underwent curative surgery and enrolled in this study. RESULTS: Overall, 25 (26.3%) of 95 patients were found to have positive cytology. The proportion of patients with positive cytology was higher in the recurrence group (36.4%) than in the groups of 5-year survival and hepatic metastases (24.6% and 26.3%, respectively), but this difference was not significant. The 5-year survival group had the lowest peritoneal CEA levels compared with the other groups, but this difference was not significant. Peritoneal cytology and CEA level alone were not sensitive, specific or accurate enough indicators in predicting survival, hepatic metastases or local recurrence. The analysis of patients with positive cytology and high peritoneal CEA level revealed that their combination can predict local recurrence with accuracy of 85%. CONCLUSIONS: The presence of free malignant cells, as detected by cytology and CEA level, in the peritoneal cavity of patients with resectable colorectal cancer had no detectable impact on survival, hepatic metastases or local recurrence rate. However, local recurrence can be predicted with accuracy of 85% in patients who have positive cytology and high peritoneal CEA level at the same time.     

大肠癌患者术中腹腔冲洗液中Survivin mRNA的检测及临床意义

目的 探讨检测大肠癌患者术中腹腔冲洗液Survivin mRNA表达的临床意义.方法 收集36例大肠癌和8例大肠良性病变患者的术中腹腔冲洗液,用RT-PCR方法 测定腹腔冲洗液中游离细胞的Survivin mRNA表达,同时作腹腔冲洗液细胞学检查(PLC).结果 腹腔冲洗液用RT-PCR方法 测定Survivin mRNA的阳性率为52.7%(19/36),高于腹腔冲洗液PLC的30.5%(11/36).Survivin mRNA的阳性率与肿瘤的组织学类型、淋巴结转移、浆膜侵犯程度、肿瘤分化程度和Dukes分期有关.结论 检测腹腔冲洗液中Survivin mRNA的表达将有助于大肠癌的预后的判断及治疗方案的制定.该法较PLC方法 有更高的灵敏度和特异性.     

Influence of colorectal laparoscopic surgery on dissemination and seeding of tumor cells

Background This study aimed to compare the influence of colorectal laparoscopic surgery and conventional surgery on dissemination and seeding of tumor cells. Methods Intraoperative peritoneal lavage cytology was performed for 36 patients with colorectal cancer during colorectal laparoscopic surgery and for 45 patients with colorectal cancer during conventional surgery. Cytology was examined twice: immediately after opening of the peritoneal cavity and just before closure of the abdomen. Saline was poured into the peritoneal cavity, and 100 ml fluid was retrieved after irrigation. Laparoscopic instruments were lavaged after surgery with 100 ml of saline. Carbon dioxide (CO₂) was derived through the trocar side orifice after pneumoperitoneum during laparoscopic coloectomy and filtered through 100 ml of saline. Cytologic examination of the filtrate was performed after the filtration process, smear, cell block, and staining. Results Malignant cells were not detected in the CO₂ filtrate gas. The incidence of positive cytology in the lavage of the instruments during laparoscopic surgery was 2.78%. The incidence of positive cytology during laparoscopic surgery was 33.33% in the prelavage and 8.33% in the postlavage. The incidence of positive cytology during conventional surgery was 33.33% in the prelavage and 11.11% in the postlavage. Conclusion During colorectal laparoscopic surgery, CO₂ pneumoperitoneum does not affect tumor cell dissemination and seeding. In this study, laparoscopic techniques used in colorectal cancer surgery were not associated with a greater risk for intraperitoneal dissemination of cancer cells than the conventional technique.     

Role of pleural lavage cytology before resection for primary lung carcinoma

OBJECTIVE: To investigate the role of pleural lavage cytology (PLC) in resection for primary lung carcinoma. SUMMARY BACKGROUND DATA: The prognostic significance of PLC before manipulation is still controversial. METHODS: Cytology of pleural lavage immediately after thoracotomy but before any manipulation of the lung was examined in 500 consecutive patients with lung cancer with no pleural effusion who underwent pulmonary resections. Eighteen patients who already had pleural dissemination were excluded from this study. RESULTS: Eighteen of 482 patients (3.7%) had positive cytologic findings. The positivity of PLC was significantly correlated with histology, extension of tumor to pleura, and presence of lymphatic permeation or vascular involvement by tumor. Positive lavage findings were seen only in adenocarcinoma. Because 6.3% of the patients with adenocarcinoma had positive cytologic findings, it is vital to perform PLC before curative resections for lung cancer, especially adenocarcinoma. The 5-year survival rates of the patients having negative and positive lavage findings were 52.9% and 14.6%, respectively. The prognosis of the patients with positive lavage findings was as poor as that of the patients with stage IIIB disease and that of the patients with malignant effusion. CONCLUSIONS: Positive findings on PLC indicate exfoliation of cancer cells into the pleural cavity, which is an essential prognostic factor. In addition, we should regard positive cytologic findings as a subclinical malignant pleural effusion that is pathologic stage T4.     

Peritoneal cytology in colorectal cancer: incidence and prognostic value

BACKGROUND: The value of peritoneal washing cytology on prognosis is not clear yet. The aims of our prospective study were to consider the incidence and prognostic value of peritoneal cytology. METHODS: From 1996 to 2003, washing cytology was performed in 88 patients who underwent surgery for colorectal cancer. Before exploration and manipulation of the tumor, each of the peritoneal cavities next to the tumor site, subhepatic and rectovesical recesses, were irrigated with 50 mL saline, and then the aspirates were taken for cytological evaluation. RESULTS: Thirteen (14.7%) of 88 patients had positive cytology. Although necrosis, depth of invasion, differentiation of the tumor, macroscopic peritoneal dissemination, and ascites were correlated with positive cytology; multivariate analyses revealed the depth of invasion, presence of necrosis, and differentiation of the tumor as the factors affecting the cytology. The disease-free and overall-survival times in patients with positive and negative peritoneal washing cytology were 56.36, 61.40 and 52.08, 63.94 months, respectively (P > .05). CONCLUSION: The presence of free malignant cells in the peritoneal cavities of patients who underwent curative resection for colorectal cancer provides no further prognostic value over the current staging systems.     

A search for malignant cells in peritoneal fluid from patients with colorectal adenocarcinoma

Cytologic examination of peritoneal fluid aids in staging ovarian malignancies and in selecting gastric adenocarcinoma patients for intraoperative adjuvant chemotherapy. Tissue culture of peritoneal fluid could be potentially valuable in confirming cell viability and establishing sensitivity to a variety of anti-cancer agents. It also could be a more sensitive diagnostic tool than cytologic examination alone. We obtained peritoneal fluid specimens from 29 patients at the time of celiotomy: 22 had colorectal adenocarcinoma and seven were controls. Cytologic examination on a portion of each specimen produced only one positive result for malignant cells. Tissue culture of the remainder of the specimens grew cells from all but one of the patients with colon cancer; however, their morphology was similar to the fibroblasts and mesothelial cells that grew from the seven controls. We speculate that these negative results stem from the absence or reduced number of tumor cells in the specimens. Without additional refinement of our methods of specimen collection and processing, cytologic examination and tissue culture of peritoneal fluid from patients with colorectal cancer are of minimal value. Nevertheless, we believe that, with the necessary refinements, they may eventually become invaluable in the management of these patients.     

实时荧光定量PCR检测结直肠癌腹腔CEA水平及其临床意义的研究

目的:应用实时荧光定量PCR技术检测结直肠癌腹腔内CEA水平并探讨其临床意义.方法:2003年5月至2004年3月,收集在日本爱知癌症中心手术107例结直肠癌病例的腹腔冲洗液,每个样本的cDNA应用随机引物合成,并在罗氏的实时荧光定量PCR(LightCycler)上进行定量分析.每个样本同时进行常规细胞学检查.所有病例术后经过平均为1年的随访.结果:CEA mRNA的阳性率和水平均与肿瘤的侵润度(T),分期以及淋巴结转移相关.在一个合理界定值上,CEA和CK-20检测的敏感度与特异度均为100%和100%,而常规的细胞学检查则为33%和100%.结论:CEA定量分析是检测结直肠癌腹腔微转移的敏感和特异的方法,CEA mRNA水平的异常与术后的无瘤生存率显著相关.其临床意义有待于更长期的随访结果.     

CEA RT-PCR检测胃癌腹腔灌洗液游离癌细胞临床价值的初步观察

目的：初步观察癌胚抗原(CEA)逆转录．聚合酶链反应(RT-PCR)检测胃癌腹腔洗液中游离癌细胞的临床价值。方法：收集36例进展期胃癌和6例慢性胆囊结石病人腹腔灌洗液100ml，其中50ml行CEA RT-PCR，扩增CEA特异性片断；50ml行细胞学检查。胃癌细胞株MKN-45为阳性对照。结果：36例胃癌病人腹腔灌洗液中14例于131 bp处见CEA的特异性条带，阳性率为38．9％(14／36)；6例慢性胆囊结石病人腹腔灌洗液RT-PCR结果均为阴性；MKN-45在131bp处发现CEA的特异性条带。细胞病理学检查，36例胃癌病人中有6例腹腔灌洗液中发现有肿瘤细胞或核异形细胞，阳性率为16．6％(6／36)，且此6例RT-PCR结果均为阳性；8例RT-PCR结果阳性病人的细胞学检查为阴性。CEA RT-PCR的阳性率与肿瘤胃壁浸润深度、淋巴结转移数和胃癌分化程度明显相关。随访至今，36例进展期胃癌病人中CEA RT-PCR检查阴性的病人尚无一例腹腔内肿瘤复发，1例细胞学检查阴性而CEA RT-PCR阳性的病人术后4个月时出现腹腔内肿瘤复发。结论：腹腔灌洗液中胃癌细胞CEA mRNA的RT-PCR检测法敏感性较高．初步临床观察及随访显示该法有望作为诊断腹腔内游离癌细胞的有效辅助手段。     

Free intraperitoneal tumors cells in pancreatic cancer--significance for clinical course and therapy]

Intraoperative peritoneal cytology was performed in 36 patients with pancreatic ductal adenocarcinoma. 12 patients (33%) showed malignant cells in the peritoneal cavity. In the further course these patients developed more non-local metastases and had a significantly shorter survival rate. Peritoneal carcinomatosis became evident in 75% of the patients with free cancer cells in contrast to only 14% of the patients without. Detection of free cancer cells was directly related to the histological tumor stage (TNM-system). Iatrogenic shedding of malignant cells by surgical tumor manipulation or needle biopsy was not observed. The technique of intraoperative peritoneal lavage with consecutive cytology and its possible effects on further treatment is discussed.     

检测腹腔灌洗液中细胞内端粒酶活性对结直肠癌患者的诊断价值

目的探讨测定腹腔灌洗液中细胞内端粒酶活性对检测腹腔中游离癌细胞的敏感性。方法采用原位分子杂交(ISH)技术测定28例结直肠癌患者术始、术毕腹腔灌洗液中细胞内端粒酶活性,同时与常规细胞学检查结果进行比较。结果28例结直肠癌患者术始、术毕腹腔灌洗液中细胞内端粒酶阳性率分别为42.9%(12/28)和21.4%(6/28),P>0.05;差异无显著性意义。常规细胞学检查游离癌细胞阳性率术始、术毕分别为14.3%(4/28)和3.6%(1/28);两者差异也无显著性意义(P>0.05)。术始,腹腔灌洗液中细胞内端粒酶阳性率为42.9%,细胞学检查阳性率为14.3%,两者差异有显著性意义(P<0.05);术毕,腹腔灌洗液中细胞内端粒酶阳性率为21.4%,细胞学检查阳性率为3.6%,两者差异有显著性意义(P<0.05)。原发癌肿已侵出浆膜层者和原发癌肿侵及和未侵及浆膜层者,术始腹腔灌洗液中细胞内端粒酶阳性率分别为73.3%和7.7%,两者差异有非常显著性意义(P<0.01);腹腔灌洗液中细胞内端粒酶阳性与临床原发癌肿侵出浆膜层呈正相关,但与原发癌肿大体类型、组织学类型及有无淋巴结转移均无关(均P>0.05)。结论用ISH技术测定腹腔灌洗液中细胞内端粒酶活性对检测腹腔中游离癌细胞的敏感性明显高于常规细胞学检查。     

Long-term outcomes of laparoscopic surgery for colorectal cancer

Multiple reports have outlined the potential benefits of the laparoscopic approach to colon surgery. Recently, randomized control trials have demonstrated the safety of applying these techniques to colorectal cancer. This study examined the long-term follow-up assessment of patients after laparoscopic colorectal cancer resections and compared them with a large prospective database of open resections. A total of 231 resections were performed for adenocarcinoma of the colon or rectum between 1992 and 2004. Of these 231 resections, 93 were rectal (40.3%) and 138 were colonic (59.7%). A total of 8 (3.2%) of the resections were performed as emergencies, and 27 (11.7%) were converted to open surgery. The mean follow-up period was 35.84 months (range, 0-132 months). The disease recurred in 51 of the patients (22.1%) before death, involving 14 (6.1%) local and 37 (16%) distant recurrences. Only two patients had wound recurrences (0.8%), and both patients had widespread peritoneal recurrence at the time of diagnosis. The overall survival rate was 65.3% at 60 months and 60.3% at 120 months. The disease-free survival rate was 58% at 60 months and 56% at 120 months. Laparoscopic techniques can be applied to a wide range of colorectal malignancies without sacrificing oncologic results during a long-term follow-up period.     

Implications of peritoneal cytology for staging of early pancreatic cancer.

Cytologic examination of peritoneal washings was performed in 40 patients with pancreatic ductal adenocarcinoma (35 head, 5 body) whose tumors had been selected as potentially resectable by computed tomographic (CT) findings. Saline (100 mL) was instilled and aspirated at laparoscopy in 27 patients and at laparotomy in 13. Malignant cells were found in the peritoneal washings in 12 of 40 patients (30%): 29% in cancers of the pancreatic head versus 40% in the body; 33% at laparoscopy versus 23% at laparotomy; and in 4 of 8 patients with ascites versus 8 of 32 without ascites. The cytology was positive in 6 of 8 patients (75%) who had a prior percutaneous needle biopsy versus 6 of 32 (19%) of those who did not (p less than 0.01). Liver metastases were found in six patients, all with negative cytology. One of 10 pancreatic head cancers with positive cytology was resectable versus 13 of 25 with negative cytology (p less than 0.05). Survival was significantly longer in patients with negative cytology. We conclude that (1) pancreatic cancer sheds malignant cells into the peritoneum early and commonly; (2) laparoscopic lavage is an effective means of cytologic study; (3) ascites is not a precondition for cytologic study, nor does its presence necessarily imply carcinomatosis; (4) intraperitoneal spread of cancer cells may be promoted by tumor biopsy; (5) cytologic findings provide an additional index of resectability; and (6) cytologic findings appear to correlate with duration of survival. This study shows that even "localized" pancreatic cancer is often not contained and suggests caution with biopsy of potentially curable lesions.     

Prognostic value of peritoneal lavage cytology in gastric cancer

The microscopic detection of free peritoneal tumour cells in peritoneal lavage fluid in gastric cancer patients is a useful predictor of peritoneal recurrence and poor prognosis. The aim of this study was to verify the prognostic significance of intraoperative peritoneal lavage cytology and its value as a predictor of peritoneal recurrence. We evaluated the presence of free peritoneal tumour cells with extemporary cytological examination in a series of 170 peritoneal washing samples from patients undergoing gastrectomy for gastric cancer over the period from January 1992 to June 2001. Twenty-eight patients (16%) had positive extemporary lavage cytology and there were no false-negatives as compared with the final examination. All patients with positive cytology presented serosal infiltration (T3/T4). Positive peritoneal lavage cytology was a predictor of poor prognosis and peritoneal recurrence: the 24 month survival rate was 17% for positive and 60% for negative cases (P = 0.003); in positive cases 71% of recurrences were located in the peritoneum. Intraoperative cytological examination of peritoneal washings can detect the presence of free malignant cells in the peritoneal cavity and can be used to select patients who may benefit from intraperitoneal chemotherapy.     

Prognostic Value of CEA and CA 19-9 Tumor Markers Combined with Cytology from Peritoneal Fluid in Colorectal Cancer

Background  Early diagnosis and management of peritoneal metastases from colorectal cancer patients are difficult clinical challenges. The aims of this study were to evaluate the clinical significance of tumor markers and cytology in peritoneal effusions (PE) and peritoneal irrigation fluid (PI) and to determine their value as prognostic indicators in this disease. Methods  Two hundred thirty-four consecutive patients who underwent abdominal surgery for colorectal cancer from January 2006 to December 2007 were included, and tumor markers and cytology in PE and PI were analyzed prospectively. Results  The incidence of free cancer cells retrieved from peritoneal samples was 7.9%. Cytology was positive in 40.0% by Papanicolaou and Giemsa staining, 73.3% by hematoxylin and eosin staining of cell blocks, and 66.7% by carcinoembryonic antigen (CEA) and calretinin immunohistochemistry. Multivariate analysis revealed that peritoneal CEA and cancer antigen (CA) 19–9 in PI were correlated with peritoneal metastasis and cytology. Level of peritoneal fluid CEA was statistically significantly correlated with recurrence and peritoneal metastatic recurrence in patients with negative peritoneal cytology. Cytology, peritoneal CEA, and peritoneal CA 19-9 showed correlations with cancer-free survival and overall survival. Conclusions  These correlations demonstrate the importance of continuous follow-up of peritoneal metastasis if there is positive cytology or an increase in CEA and CA 19-9 in peritoneal fluid.     

Successful simultaneous operation of concomitant early gastric cancer, transverse colon cancer, and a common iliac artery aneurysm

In an 83-year-old Japanese man, concomitant bleeding colon cancer, early gastric cancer, and an expanding right common iliac artery aneurysm were evident. The patient underwent an artificial graft implantation, partial gastrectomy, and transverse colectomy, simultaneously. To protect against graft infection, the aneurysm was resected first, and then the retroperitoneum was tightly closed to isolate the graft from the peritoneal cavity. The postoperative course was uneventful, except for symptoms of temporary delirium. Recently, simultaneous surgery for concomitant abdominal aortic aneurysms and early gastric cancer has been commonly performed in Japan because the contamination of the peritoneal cavity during a gastrectomy is thought to be less severe than that during lower abdominal surgery. However, the positive rate for bacterial culture in colorectal resections is virtually the same as that in gastrectomies. Moreover, the incidence of graft infection is substantially lower than the positive rate for bacterial culture in surgery for aneurysms. Some surgeons object to a simultaneous resection due to fear of graft infection, but even the presence of infectious organisms does not always result in graft infection. The present case illustrates the benefits of a simultaneous operation for both an aneurysm and gastrointestinal malignancy.     

Feasibility of colectomy with mini-incision

BACKGROUND: Laparoscopic resection has been advocated as a method of colectomy for various colon and rectal disease. One advantage claimed by laparoscopy is its smaller incision size. The aim of the present study is to evaluate whether mini-incision is feasible along with the advantage of adequate exploration of the peritoneal cavity. METHODS: From December 2000 to November 2003, 316 patients with various colorectal diseases receiving colectomies through a skin incision less than 7 cm were analyzed. All of the colectomies were performed by a single surgeon. Exploration of the entire peritoneal cavity was possible for all the cases. There were 153 men and 163 women. Ages ranged from 19 to 90 years, averaging 62.4 years. Two hundred ninety-five patients were operated on for carcinoma of the colon or rectum; 4 had operations for villous tumors with severe dysplasia; 3 each for radiation enterocolitis and diverticulitis; 2 each for malignant stromal tumor and rectal prolapse; and 1 each for lymphoma, actinomycosis, volvulus, angiodysplasia, Crohn's disease, ulcerative colitis, and ovarian cancer with rectal invasion. There were 15 abdominoperineal resections, 97 low anterior resection, 49 anterior resections, 64 sigmoidectomies, 7 left hemicolectomies, 81 right hemicolectomies, 2 subtotal colectomies, and 1 restorative proctocolectomy. No Harmonic scalpel or laser was used during surgery. No hand-port or laparoscope was used in the series. RESULTS: Five patients died of acute respiratory failure, 2 patients died of terminal cancer, and 1 patient died of hypoglycemia due to poor control of diabetes mellitus. Complications included 11 urinary tract infections, 8 intestinal obstructions, 6 anastomotic leakages, 6 wound infections, 5 respiratory failures, 5 pelvic bleedings, 2 pneumonias, 2 gastrointestinal bleedings, and 1 pancreatitis. Small incisions did not prolong operation time. CONCLUSION: This experience suggests that the majority of colectomies can be accomplished by an incision of less than 7 cm, which is no larger than the incision size used in a laparoscope colectomy if multiple incisions made for trocars are added to the main incision length. The advantages of mini-incision include lower cost, faster completion of procedure, reduced bulkiness of equipment, and the possibility of exploring the entire peritoneal cavity by hand without loss of tactile sensation.     

How Uncommon are Isolated Lung Metastases in Colorectal Cancer? A Review from Database of 754 Patients Over 4 Years

Background  It is commonly thought that colon cancer metastases to the lungs without involvement of the liver are rare. Methods  We performed a retrospective review of all patients with colorectal cancer diagnosed between December 2003 and August 2007 in Singapore. Isolated lung metastases were determined as (1) Definite if there was confirmed histology or cytology of the lung lesion(s) in the absence of liver lesions on CT scan, and (2) Probable if there were only radiological evidence suggestive of lung metastases rather than lung primary also in the absence of liver lesions on CT scan. Results  There were 196 patients with rectal and 558 patients with colon cancer (369 left-sided and 189 right-sided). There were 13 definite isolated lung metastases, and the remaining 43 were probable. Twenty-three (12%) patients with rectal cancer and 33 (6%) patients with colon cancer had isolated lung metastases (OR 2.11, 95% CI 1.21–3.70). Patients with ≥pT3 lesions (OR 1.92, 95% CI 0.75–4.93) and ≥pN1 (OR 1.56, 95% CI 0.86– 2.83) were more likely to have isolated lung metastases. Conclusion  The true incidence of isolated lung without liver metastases in colorectal cancer is likely to lie between 1.7% and 7.2%. While the incidence of isolated lung metastases is twice as common in patients with rectal cancer, it is still significant in patients with colon cancer. The absence of liver involvement should not preclude a search for lung metastases.     

Invasive micropapillary carcinoma of the ascending colon--a report of a case

Micropapillary carcinoma (MC) has been recently recognized to be a rare but distinctive variant of adenocarcinoma. At present, only a limited number of colorectal MC cases have been reported. We present a case of MC of the ascending colon with distant metastasis. A 61-year-old female patient was hospitalized with a complaint of abdominal pain. A diagnostic work-up revealed cancer of the ascending colon with multiple lung metastases. The patient underwent a right hemicolectomy with lymph node dissection. A peritoneal nodule was observed in the abdominal cavity during surgery, and this nodule was also resected. The pathologic findings of the colon tumor revealed components of conventional tubular adenocarcinoma and micropapillary carcinoma. Lymph nodes and a peritoneal nodule revealed tubular adenocarcinoma. MC is a rare disease but has high malignant potential. In the present case the tumor was small in size, but the patient had a peritoneal and multiple lung metastases.     

Intra-abdominal lesions could be missed by inadequate laparoscopy

Laparoscopic resection has become one of the choices for colectomy for various colon and rectal diseases in recent years. Despite some uncertainties of laparoscopic procedures, especially during cancer surgery, its popularity has forced surgeons to pursue the approach. One of the concerns is inadequate examination of the intra-abdominal organs with a laparoscope. This study is a retrospective analysis of a single surgeon's experience of the frequencies of unexpected findings during laparotomies. From July 1990 to November 2005, 2775 patients with various colorectal diseases receiving laparotomies by a single surgeon were analyzed. Among them, 2282 patients were operated for primary colorectal cancer. Excluded were patients who did not receive a formal laparotomy, who had a recent laparotomy, who had peritoneal and omental metastasis, and whose pathology did not attract attention for management. Exploration of the entire peritoneal cavity was performed for all cases in the series. There were 1423 males and 1352 females. Ages ranged from 12 to 94 years, averaging 62.6-years-old. Forty-six patients (1.7%) were found to have unexpected intra-abdominal lesions during laparotomies. Eleven patients were found to have synchronous colorectal cancers; five patients were found to have unexpected liver metastases; three patients each were found to have gastric cancers, stromal tumors of the small bowel, and ectopic pancreas; two patients each were found to have gastric leiomyosarcomas, pancreatic cancers, mucoceles of the appendix, ulcers of the small intestine, bleeding Meckel's diverticula, pancreatitis, and perforations of the ileum; one patient each was found to have gall bladder cancer, malignant carcinoid tumor, pheochromocytoma, diverticulitis of the jejunum, diverticulitis of the colon, duplication of the colon, and aortic aneurysm larger than 6 cm. Forty-one of the lesions were likely to be missed by laparoscope. This experience suggests that incomplete laparotomies might miss various pathologies. Laparoscopy is not a complete form of laparotomy because of loss of tactile sensation. Laparoscopy might result in an inadequate or inappropriate management due to misdiagnosis.     

Current experience and future directions of completely NOTES colorectal resection

Clinical implementation and widespread application of natural orifice translumenal surgery (NOTES) has been limited by the lack of specialized endoscopic equipment, which has prevented the ability to perform complex procedures including colorectal resections. Relative to other types of translumenal access, transanal NOTES using transanal endoscopic microsurgery (TEM) provides a stable platform for endolumenal and direct translumenal access to the peritoneal cavity, and specifically to the colon and rectum. Completely NOTES transanal rectosigmoid resection using TEM, with or without transgastric endoscopic assistance, was demonstrated to be feasible and safe in a swine survival model. The same technique was successfully replicated in human cadavers using commercially available TEM, with endoscopic and laparoscopic instrumentation. This approach also permitted complete rectal mobilization with total mesorectal excision to be performed completely transanally. As in the swine model, transgastric and/or transanal endoscopic assistance extended the length of proximal colon mobilized and overcame some of the difficulties with TEM dissection including limited endoscopic visualization and maladapted instrumentation. This extensive laboratory experience with NOTES transanal rectosigmoid resection served as the basis for the first human NOTES transanal rectal cancer excision using TEM and laparoscopic assistance. Based on this early clinical experience, NOTES transanal approach using TEM holds significant promise as a safe and substantially less morbid alternative to conventional colorectal resection in the management of benign and malignant colorectal diseases. Careful patient selection and substantial improvement in NOTES instrumentation are critical to optimize this approach prior to widespread clinical application, and may ultimately permit completely NOTES transanal colorectal resection.