With the maturity of the technology and surgical treatment of chemotherapy, radiotherapy, biological therapy and adjuvant therapy of continu
With the maturity of the technology and surgical treatment of chemotherapy, radiotherapy, biological therapy and adjuvant therapy of continuous improvement, the treatment of colorectal cancer in China have made great progress in the past twenty years, close to the level of developed countries, but the overall survival rate of patients with colorectal cancer for 5 years but there is still a large gap. The fundamental reason is that China's colorectal cancer early diagnosis and treatment rate is low, the vast majority of colorectal cancer cases was found nearly late in the early stage colorectal cancer confined to the mucosa and submucosa, 5 year survival rate was above 90% after resection of advanced colorectal cancer, and 5 years survival rate is less than 7%. Therefore, to improve the early diagnosis and treatment of colorectal cancer is the key to improve the 5 year survival rate of colorectal cancer patients. In this paper, some opinions about the early diagnosis and treatment of colorectal cancer at home and abroad in recent years are presented.
Early diagnosis of colorectal cancer
The typical symptoms of colorectal cancer can be diagnosed easily, but in the early stage of colorectal cancer is often only some occult symptoms such as fecal occult blood or precancerous lesions of colon adenoma causes symptoms such as increased frequency of defecation, stool intermittent bleeding, even without any symptoms. To find these non typical clinical symptoms of early colorectal cancer, the most effective way is to screening and follow-up of natural population census and high-risk population; colorectal cancer risk of universal education and reduce the iatrogenic misdiagnosis is very important; improve the colonoscopy rate and node lesion recognition level of colonoscopy is to improve early the detection rate of colorectal cancer is the most direct means.
(a) natural population screening and high risk population screening and follow-up is the most effective way to improve the early diagnosis rate of colorectal cancer
Natural population census
The natural population census is the most effective way to find the early colorectal cancer and reduce the mortality of colorectal cancer. Hewitson et al. Summary of the 320 thousand - to - 18 - year census published in the West in recent years shows that the cumulative risk of death from colorectal cancer has dropped by an average of about $16% on average in. Li Shirong and a group of 16 years of the census report shows: colorectal cancer DukesA/B was detected by the census of population accounted for 94%, 5 years after the surgery survival rate reached more than 75% colorectal cancer DukesA/B but not found in the census of population accounted for only 29%, 5 year survival rate was 33%. Obviously, it is impossible for a developing country with a population of 1 billion 300 million to achieve a nationwide census at this stage. But at least in the high incidence of colorectal cancer in the high incidence of natural population census. Zheng Shu on the high incidence of colorectal cancer in Zhejiang County of Jiashan > 30 year old natural population of 62667 census, found 34 cases of colorectal cancer, calculate the detection rate of 54.3/105 staging of colorectal carcinoma, DukesA/B accounted for 71.4%, the importance of the natural population census visible.
The natural population census currently used is still the most fecal occult blood test (FOBT), and colonoscopy on positive patients. Because the FOBT has a high false positive rate and low specificity, greatly increasing the cost of follow-up, at present there are some promising detection methods such as feces, fecal coliform cytology and fecal exfoliated cell DNA markers.
Cytology fecal coliform: normal mucosa every 24 hours from 1 to 5 * 1010 epithelial cell shedding, and the update speed of tumor epithelial cells faster, every day about 1% of the cells falling into the intestine and excreted with the feces. The difference is that normal mucosa shedding is mainly apoptosis, and colorectal cancer tissue loss is mainly large cytokeratin positive staining of colon cells and inflammatory cells, and colon cells shedding still retains characteristics of the expression of tumor associated antigen. Collecting the exfoliated epithelial cells in the stool for routine pathological examination, which has a high specificity for the diagnosis of malignant tumors .
Fecal exfoliated cell DNA markers: the study found that DNA can exist stably in the feces, and sustainable from the colorectal mucosa shedding, using PCR amplification technique can trace of DNA detection in stool, some scholars in detection of fecal exfoliated cell DNA content found in diagnosis and prognosis of colorectal carcinoma has high sensitivity and specificity that can be used as a new simple and effective non-invasive screening test.
High risk population screening and follow-up
At present generally accepted the following object for the high risk population of colorectal cancer: familial adenomatous polyposis (FAP) and hereditary non polyposis colorectal cancer (HNPCC) family members over 20 years old, I or first-degree relatives of colorectal cancer has a history or history of intestinal polyps, inflammatory bowel disease patients, requirements as for the high risk of colonoscopy.
FAP family members: FAP is an autosomal dominant genetic disease, the next generation prevalence rate was 50%, the penetrance of the disease was about 95%, and the canceration rate was about 100%. Therefore, each family member should receive genetic testing, clear whether gene carriers (APC gene on the long arm of chromosome fifth mutation). If the carrier, from the age of 20 should be a colonoscopy every year, once there are multiple polyps should be prophylactic removal of the entire colon.
HNPCC family members: HNPCC family members according to the proband gene mutation law of corresponding gene detection, once the forecast positive, there were 80% patients in the future may be cancer, these members should be early intervention, from the age of 20, every 1 ~ 2 years follow-up colonoscopy in 1, after 40 years old check 1 times a year. The results showed that the gene carriers (hMLH1, hMSH2, hMSH6, hPMS1, hPMS2 and other mismatch repair gene mutations) from the age of 20 began to increase the risk of colorectal cancer, and small adenomas can quickly develop into cancer.
I have a history of colorectal adenoma: colonoscopy revealed multiple adenomas or 1 > 1
Cm should be 1 to 3 years of adenoma, check a colonoscopy; if it is less than a single 0.5cm adenoma can review colonoscopy every 5 years.
I suffered from colorectal cancer: first years after surgery, 1 full colonoscopy, such as normal, 3 years after the check, check again is still normal, but every 5 years of colonoscopy. Any time a colonoscopy found adenoma, should be carried out supervision and inspection according to the history of colorectal adenoma.
I was suffering from inflammatory bowel disease: according to statistics, the rate of canceration of ulcerative colitis and disease duration, disease 10 years canceration rate is 2%, 20 years in 8%, 30 years after 18%. For more, a wide range of diseases of ulcerative colitis, should be sick after 8 years, every 1 to 2 years were examined 1 times total colonoscopy; if the lesions involving only the left colon can be monitored in sick 15 years after colonoscopy.
(two) the prevalence of colorectal cancer risk education and the reduction of iatrogenic missed diagnosis and misdiagnosis are the important content to improve the early diagnosis of colorectal cancer in China
1 Population Health Education
In China, people for decades before the symptoms is a medical model for the doctor, the lack of active attention to the health consciousness, to insist that intermittent bowel bleeding hemorrhoids attack without medical treatment is still There are plenty of people who. In the outpatient work often found that some patients with rectal cancer history of more than 1 years, asked the reason for the delay of medical treatment are mistaken for hemorrhoids and do not attach importance to. Therefore, consciously for colorectal cancer prevention in the natural population, people take the initiative to accept the check, improve the sensitivity to the intestinal danger signal, is the present stage cannot be achieved in the national census must be feasible and give enough attention to the means of. In the past 5 years, Zhejiang Province People's Hospital in the outpatient service to carry out the prevention and treatment of colorectal cancer, as far as possible to persuade patients with high risk factors for colonoscopy, the detection rate of early colorectal cancer increased from 6.5% to 16.3%.
2 to reduce iatrogenic missed diagnosis and misdiagnosis
In the clinical investigation of 2573 cases of colorectal cancer in Zhejiang Province People's Hospital and we found that 61.6% of the cases in the history of more than half a year before being diagnosed, including 65.3% cases of patients because of their neglect, and the other is 34.7% cases of iatrogenic misdiagnosis. In these cases, some clinical doctors for intermittent irregular bowel movements accompanied by mucus of patients with chronic colitis most probably it did not actually happen to diagnose treatment; some patients with intermittent hematochezia satisfied with "hemorrhoids"; what is more even dre do not delay and lower rectal cancer. In a few months for the treatment of anemia and ultimately diagnosed in advanced colorectal cancer. A small number of cases have been followed up by a barium enema or colonoscopy, but they are missed because of poor quality. Therefore, to improve the level of diagnosis and reduce the misdiagnosis and missed diagnosis is the key to the early diagnosis of colorectal cancer.
(three) the most direct means to improve the detection rate of early colorectal cancer is to improve the rate of colonoscopy and the identification of the lesions
Colonoscopy is the most direct means of detecting colorectal tumors, and any other indirect signs found in all other tests must be confirmed by colonoscopy. In recent years, the enlargement of the magnifying endoscopy and the narrow band endoscope have appeared, so that the detection rate of small lesions is greatly improved. However, because of the risk and pain of colonoscopy, the rate of acceptance of colonoscopy is significantly restricted. Therefore, advocating painless colonoscopy, improve the acceptance rate of colonoscopy colonoscopy, master advanced technology, improve the detection rate of lesions is the key for improving early diagnosis of colorectal cancer rate.
1 promote comfortable endoscopy and improve the acceptance rate of colonoscopy.
The patient's fear of colonoscopy is the biggest obstacle to colonoscopy, and the introduction of painless colonoscopy is an effective way to eliminate the disorder and improve the acceptance rate of colonoscopy. Zhejiang Province People's Hospital since 2005 to carry out a comprehensive painless endoscopy, colonoscopy first diagnosis acceptance rate increased from 35% to 90%, the proportion of 78% painless colonoscopy. It should be stressed that this is due to painless colonoscopy patients for operation in response, risk of complications increased, therefore requires the operator must have a colonoscopy skilled.
2 master the advanced technology of colonoscopy, improve the recognition of early colorectal cancer and precancerous lesions.
Most of the lesions of the colon under endoscope are protuberant lesions, while the flat lesions are very few, but they are closely related to the occurrence of colorectal cancer. It is easy to find that the traditional endoscopic lesions, but often missing small flat lesions, enlarged by chromoendoscopy was sprayed to the pigment can outline the contours of the lesions, clearly show the subtle changes in the shape and arrangement of intestinal mucosal glandular openings, so as to improve the recognition of the disease. There are 0.3% commonly used pigment indigo carmine (Indigo carmine) and methylene blue (Methylene 0.2% ~ 0.5%
Japanese scholar Kudo will enlarge the staining of endoscopic mucosa crypt morphology is divided into five types (Pit Patten classification): type I is a circular recess, the arrangement is neat, no atypia, generally normal glandular openings and non lesion; II
Type were stellate or papillary, arranged neatly, no atypia, pit size uniform, mostly inflammatory or proliferative lesions and non adenomatous; type III is divided into two subtypes: L III called large tube type, larger than normal crypt morphology and regular arrangement, no special structure as the basic form of uplift, of which about 86.7% of adenoma, adenoma, remaining mucosa cancer; III s called glandule canal type, is smaller than normal crypts and crypt without agglomeration, branches, the basic form for depression type tumors, this type of highly atypical adenoma has high incidence rate, can also be found in mucosal carcinoma (28.3%), type IV branch and gyriform, for this type of crypt lesions of P, I sp, i s see more, similar to coral like changes seen in villous adenoma, intramucosal carcinoma can be accounted for 37.2%. Type V V (A
Irregular type) or V N (unstructured), disappear, this type of form or structure in the crypt disorder cancer, submucosal cancer accounted for 62.5%. Tamura et al. Found that by Pit
Patten classification criteria for the diagnosis of intestinal mucosal lesions, magnifying staining endoscopy and histopathological diagnosis of the consistency of up to 90%. Hurlstone et al. Also found that the sensitivity of magnifying endoscopy in differentiating neoplastic and non neoplastic lesions was 98%, with a specificity of 92%.
Narrow band endoscopy (NBI) appears to simplify the staining procedure. NBI with a wavelength of 500 nm, respectively, 445
Nm and 415 nm narrow spectrum light source, to obtain an image of 240 m, 200 m and 170 m depth of the mucosa, and because of the maximum absorption value of hemoglobin at 415nm, the mucosal vascular network showed a clear brown. Hirata M NBI with magnifying endoscopy and magnifying endoscopy to do comparative research, results show that the consistent rate between the two Pattern for the diagnosis of Pit type 88%, s type III, 100% of type III L 98%, type IV and V 88% A type 78% and type 100% V N. Su MY, respectively, with NBI endoscopy and staining endoscopy (0.2%)
Indigo Carmine was performed on 78 patients and Pit Pattern typing was performed. The results showed that the sensitivity, specificity and accuracy of NBI endoscopy and endoscopic endoscopy in differentiating neoplastic and non neoplastic colorectal polyps were the same. Compared with chromoendoscopy, endoscopic mucosal vascular network NBI can display well, better contrast between the lesions and the surrounding tissue, is conducive to the discovery and diagnosis of flat lesions, and NBI endoscopy is performed only in conversion of two kinds of light source, without spraying pigment, convenient time-saving and avoid the harm of chromoendoscopy on the human body potential.
Two, minimally invasive treatment of early colorectal cancer
According to the concept of modern surgical treatment, it is necessary to improve the quality of life of patients with cancer
Quality of life, QOL). Under the guidance of this idea, the minimally invasive treatment of tumor has been paid more and more attention by doctors and patients. Minimally invasive treatment of early colorectal cancer was performed by endoscopic snare excision (snare resection, SR), endoscopic mucosal resection (endoscopic mucosal, EMR) and endoscopic mucosal resection (resection)
Endoscopic piecemeal mucosal resection, EPMR), endoscopic submucosal dissection
Submucosal (endoscopic dissection, ESD) and colonoscopy combined with laparoscopic resection of early colorectal cancer.
According to the endoscopic diagnosis of early colorectal cancer will generally be divided into the uplift, surface and lateral development type (lateral spreading tumor, LST) three. It is also known as type I, and can be divided into pedicle type (I P), Adige (I sp) and sessile type (i s). Pedunculated type cancer often confined within the mucosa and submucosa, rarely invade (M cancer), Iati and sessile type malignant with submucosal carcinoma (Sm carcinoma). Surface type, also known as type II, can be divided into surface uplift type (II a), surface flat type (II B) and surface depression type (II C). LST is the lateral growth than a low uplift above lesions to grow strong, the appearance of granular or nodular cluster.
SR is suitable for P type and PS type I of early colorectal cancer; i s type, a type, type II EMR is suitable for early colorectal cancer than 3cm; > 1 type s and 3cm type IIA, IIb type of early colorectal cancer with EPMR; ESD is suitable for C type and LST type early colorectal cancer. In addition to SR, in the other endoscopic resection of early colorectal cancer should be carried out under the focus of physiological saline or epinephrine saline submucosal injection test, if there is no bulge after injection (the)
Sign, indicating that there is a deep infiltration, which is no longer suitable for endoscopic treatment, which can reduce the incidence of bleeding and perforation after treatment, and the margin should be as much as possible beyond the tumor edge 1cm. Endoscopic ultrasonography is helpful in determining the depth of invasion and lymph node metastasis. When the tumor is large, the endoscopic treatment has a high risk of intestinal perforation, it can be operated under the supervision of laparoscopy. If there is no obvious bulge, endoscopic ultrasonography clearly have deep invasion or lymph node metastasis, endoscopic localization of colorectal cancer can be performed.
Pathological evaluation of endoscopic resection of early colorectal cancer. Japanese scholars identify endoscopic specimens without marginal resection of cancer cells should meet the following criteria: each slice edge no cancer cells; each slice length should be greater than the adjacent sections of cancer tumor length; the distance from the edge of specimens of broken ends should be 1.4 mm in well differentiated tubular adenocarcinoma, moderately differentiated tubular adenocarcinoma is 2 mm. The shortest distance is greater than or equal if the lesion edge and resection of 2 mm (corresponding to the normal glandular tube more than 10) for complete resection, and 2 < mm is not completely removed when resection still had residual cancer cells when residual resection. Yasuda study showed that EMR specimens such as vascular invasion, sprouting (tumor budding) and submucosal infiltration significantly, significantly increased the risk of lymph node metastasis, these patients should receive further surgical treatment. Bergmann et al. Were treated with EMR or EPMR in 59 cases of colorectal adenoma and 6 cases of early colorectal cancer. The lesions were in the range of from 10 to 50mm. All cases were resected completely except for 2 cases with positive resection margin. Complications included 1 cases of bleeding and perforation in 1 cases. After an average follow-up of 18 months, no recurrence was found in all the patients with colorectal cancer in 6 cases. Fujishiro et al. Reported 35 cases of rectal cancer with ESD, including adenoma in 17 cases, non invasive carcinoma in 13 cases, Sm1 carcinoma in 2 cases, Sm2 carcinoma in 3 cases. The complete R0 resection rate was 89%, and more than 3 patients with Sm2 were treated with further surgery. Perforation occurred in 2 cases (5.7%). 31 cases were followed up for 3 years. Saito et al. ESD was applied to treat 200 patients with large surface type of early colorectal cancer, including tubular adenoma in 51 cases, mucosal carcinoma in 99 cases, Sm3 in Sm1 in 22 cases, and Sm2 in 28 cases. The average diameter was 38mm. 10 cases (5%) had perforation, bleeding occurred in all of the 4 patients (2%), and only in the emergency surgery in 1 cases. The total resection rate and cure rate were 84% and 83%, respectively. As long as the indications, early colorectal cancer endoscopic treatment is safe.
From EMR to ESD is a major advance in endoscopic therapy for early colorectal cancer. ESD treatment of early colorectal cancer, not only can get a similar effect with surgical treatment, and most of the patients from the traditional surgical treatment of the risk and the serious impact on the quality of life after surgery. In Japan and Hongkong, ESD has become a safe, reliable and effective method for the treatment of one-time complete resection of intestinal mucosal carcinoma.
Zheng Minhua, colonoscopy combined with laparoscopic operation for 46 cases of colorectal cancer, including 21 cases of malignant polyps, all cases after 1 to 21 months of follow-up without recurrence. Laparoscopic surgery combined with endoscopic colorectal cancer, using combined laparoscopic and endoscopic techniques for local excision of rectal cancer or tumor resection by laparoscopic intestinal tumor resection and endoscopic guided laparoscopic assisted endoscopic. This technology enables endoscopic polyp removal or large intestinal cavity after tumor resection in monitoring and assisting laparoscopic can more safely and avoid unnecessary wide excision or radical surgery; and in laparoscopic resection of colorectal cancer, accurate positioning colonoscopy can make the laparoscopic operation more radical edge reliable tumor. But for patients who need to accumulate some experience of laparoscopic and endoscopic surgery.
Early diagnosis and treatment of colorectal cancer is a weak link in the prevention and treatment of colorectal cancer in china. To strengthen the research on the biological behavior of early colorectal cancer, diagnostic criteria of early colorectal cancer, improve the early diagnosis of colorectal cancer, colorectal cancer, carry out multicenter endoscopic treatment of minimally invasive treatment of large sample, randomized controlled clinical study of early, widely according to evidence-based medicine, and to guide clinical practice, is the key to improve my in the overall level of diagnosis and treatment of colorectal cancer.