Colorectal cancer: symptoms, treatment, prognosis, stages and metastases
Colorectal cancer — a collective term that includes epithelial neoplasia of the colon and rectum. The disease affects mainly older people, often male, and is widespread in economically developed countries.
There has recently been a significant increase in the incidence of colorectal cancer. Almost every tenth case of established malignancy is carcinoma of the intestine, and the disease came to the fourth position in the list of cancer. The highest frequency observed in the United States, Western Europe, and Australia. Much less suffer the inhabitants of Asia and Africa.
Still not determined for sure the cause of cancer of the colon. It is assumed the combined influence of external conditions, lifestyle, and heredity. Diet with an abundance of meat products and lack of fiber, low physical activity, abuse of fried and fatty foods predispose to increased carcinogenic effects on the bowel wall.
Among the precipitating factors also polyps, inflammatory disease of the colon — ulcerative colitis, Crohn’s disease. Equally important are the bad habits (Smoking, alcohol abuse) that contribute to poledourisbasil, chronic colitis and cancer. Chronic fissures the anal canal, chronic constipation can cause rectal cancer.
Colorectal cancer refers to those tumors that if detected early give good numbers of survival and cure. This is largely due to the introduction of screening, enabling to start treatment in the early stages of the disease. At the same time, and running form more is not uncommon. In view of nespecificnomu symptoms cancer may long remain outside the purview of oncologists.
Symptoms of colorectal cancer
Symptoms of colorectal cancer, especially its treatment and prognosis are determined by the stage of the tumor, which is established on the basis of its size, speed and nature of growth of metastasis. There are 4 stages of the disease:
- The first stage is represented by the small size of the tumor node with clear boundaries, which does not go beyond the submucosal layer of the colon. The carcinoma has not metastasized.
- In the second stage, the cancer grows into the muscle layer and can give a single regional nodal metastases.
- At the third stage, the tumor spreads to adjacent organs and metastasized actively.
- Stage IV — carcinoma of any size and type of growth, but giving distant metastatic foci.
Metastases of colorectal cancer can be detected in mesenteric lymph nodes, colourfully etc. and distant metastasis is possible in the supra — and infraclavicular nodes. By hematogenous cells to cancer fall mainly in the hepatic tissue, but can be detected in the lungs and bones. Tumor, germinating in the intestinal wall to the serous layer that could disseminirovanne of the peritoneum, giving the implant causing metastasis and carcinomatosis.
Symptoms of colorectal cancer depend on the location of the tumor, stage of complications. For a long time the disease may have latent period, especially for tumors of the right side of the colon. In this Department the contents of the liquid, and the lumen is quite large, so usually takes a long period of time before the disease will manifest itself.
Cancer of the left half of the colon will be manifested sooner than the right one, as there the stool start to get rid of water and thicken, causing the growing tumor, which, moreover, has a tendency to stenotic growth. Colon cancer is bleeding, and it becomes one of the first symptoms of trouble, so even with hemorrhoids and other nonneoplastic lesions blood in the stool should be a cause to the exclusion of cancer.
Dyspeptic disorders characteristic of colonic carcinoma of any localization. The patient in this case complains of pain, rumbling, bloating, belching, bad taste in the mouth, vomiting. If the tumor has invaded the colon of the division to the stomach, the vomit formed fecal contents of the intestine, which is extremely painful for the patient.
The first signs of cancer of the right half of the colon is usually reduced to dyspeptic disorders. The patient complains of discomfort in the abdomen, violations of the chair, weakness caused by anemia. In the later stages with pain, increases toxicity, possible intestinal obstruction. The lean patients a large tumor available to probe through the abdominal wall.
Carcinoma of the left half of the colon are prone to stenosis of the lumen of the body, so early signs may be nonspecific symptoms — bloating, rumbling, constipation alternating with profuse diarrhoea, possible intestinal colic. In the chair present impurities of blood, mucus.
Cancer of the rectum accompanied by pain in the region of the anal canal, stool disorders, pain during defecation and separation of blood. Blood in the stool — a rather characteristic symptom of rectal cancer.
Already in the early stages of tumor may show signs of intoxication and metabolic disorders — weakness, fever, fatigue, associated with metabolic disorder, anemia, poisoning of the body products of tumor growth.
For stenosing neoplasia of the large intestine high risk of difficulty of the content up to the passage of intestinal obstruction, which is indicated by the following symptoms:
Neoplasms of the rectum do not give the prominent symptoms of intoxication due to the fact that the products of tumor growth are not absorbed into the systemic circulation. The clinic is at the forefront of pain, feeling of incomplete emptying of the bowels, impurities of blood, pus and mucus in the stool. Unlike hemorrhoids, fresh blood is the first defecation.
Prevalence of symptoms of certain manifestations of cancer has allowed to identify several clinical forms of the disease:
- Toxic-anemic — is dominated by signs anemizatsii in the form of weakness, tendency to fainting, fatigue on the background of the phenomena of intoxication and fever.
- Enterocolitica — occurs with symptoms of intestinal inflammation, stool disorder.
- Dyspeptic form is manifested by pain syndrome, dyspepsia (rumbling, bloating, diarrhea and constipation, vomiting), weight loss.
- Obstructive — is characteristic of stenosing cancers and is manifested by bowel obstruction.
Metastasis is one of the main hallmarks of malignant tumors. Colorectal cancer is actively metastasize through the lymphatic ducts into local and distant lymph nodes, and hematogenous — liver, first take on «blow» carcinoma, because the blood flowing to her from the gut via the portal vein. Metastatic site in the liver causes jaundice, pain in right abdomen, enlarged liver.
Malignant tumors of the colon tend to lead to serious complications, the most common of which I think bleeding. Recurrent bleeding can result in anaemia and massive can be deadly. Another possible complication of intestinal tumors is the need due to the closure of the lumen of the intestine tumor.
A serious complication of cancer that requires urgent surgery, is perforation of the intestinal wall with subsequent peritonitis. In advanced stages, complications can be combined and then the risk of surgical intervention increases significantly.
Video: symptoms of colorectal cancer in the «About the main thing»
How to detect cancer?
Diagnosis of colorectal cancer involves screening predisposed individuals, as well as a targeted survey of people with symptoms suspicious of cancer of the colon and rectum.
The term «screening» means the complex of measures to ensure early diagnosis of disease in a wide range of individuals In the case of colorectal cancer, its value is difficult to overestimate, because the disease may be asymptomatic or with minimal symptoms until the tumor is of considerable size, or even the beginning of metastasis. It is clear that in the absence of complaints, the patient is unlikely he will go to the doctor, so for those at risk of developed compulsory survey within the framework of the examination of the population.
Screening for cancer of the colon and rectum include:
Subject to screening people with increased risk of colorectal carcinoma. Among them, those who have the closest blood relatives with the described pathology, as well as patients with inflammatory diseases, adenomas, polyps of the colon. These persons have shown a preventive diagnosis until they reach 40 years, with known cases of adenoma of the intestine in the family or the screening begins 10-15 years earlier than it was revealed the «young» cancer among close relatives.
Examination for suspected malignant tumor of the colon:
- General clinical blood and urine tests, biochemical blood tests (to detect anemia, signs of inflammation), as well as the identification of specific tumor markers (CA 19-9, cancer-embryonic antigen);
- Examination of feces for hidden blood, especially shown in carcinomas of the right side and the transverse part of the colon;
- Colonoscopy, sigmoidoscopy with taking pieces of tissue from the most suspicious areas for histological analysis.
- Radiopaque study barium suspension, CT, MRI, ultrasound.
Treatment of colorectal cancer
For the treatment of colorectal cancer the use of surgical methods, radiotherapy, chemotherapy, but surgery remains the most effective and most common way of dealing with the disease.
The type, volume and technique of surgery depend on the location of the tumor, the nature of its growth, the stage of the disease. The best results can only be achieved by early diagnosis, but even under the presence of a single metastasis, surgical treatment is carried out and allows you to extend the life of patients.
When the tumors described by localization the main point is the removal of a fragment on education, the regional lymph apparatus and fiber. In advanced stages of growth are subject to removal and other nearby tissues involved in neoplastic growth. After excision of the tumor tissue often requires reconstructive and restorative operations that can be performed immediately or some time after a bowel resection.
The presence of complications of the tumor in the form of peritonitis, intestinal obstruction, perforation makes the long-running operation is very risky, and the result it quite natural can be unsatisfactory, therefore, in such cases, surgeons have resorted to two — and even three-stage treatment when urgently removed the tumor and eliminates symptoms of its complications, and then, after stabilization of the patient, and plastic. The period between operations is usually the patient spends with a functioning colostomy.
The location of the tumor node is a key point that determines the kind of surgery. For cancer of the right colon is most often performed to remove the entire half of the body, the right hemicolectomy. Such a volume is carried out in cases where the neoplasia is limited to the caecum in connection with the anatomy and blood supply, predisposing to metastasis and spread of the disease in the overlying units.
In carcinoma of the hepatic angle of the colon surgeon had to do a hemicolectomy, extended to the middle third of the transverse part of the large intestine, crossing during the operation of supply vessels.
Cancer of the transverse colon can be removed by resection of the fragment body, but only in the earliest phases of tumor growth. In other cases, it shows the removal of the entire transverse section of the intestine. If the neoplasia was formed in the left half of colonic intestine, then a left hemicolectomy.
Tumors of the rectosigmoid Department present the greatest difficulties from the point of view of surgical treatment due to the need of the patient, where possible, the natural act of defecation. They often require complex plastic surgery, and in severe cases, the patient has to put up with irrecoverable loss of the ability of normal emptying of the rectum.
Neoplasia of the sigmoid and upper part of rectum most favorable to the integrity of the anal canal and sphincter, as can be removed by resection with restoration of normal bowel. When tumors of the lower rectum are shown either sphincter surgery (brusnianka resection) or total removal (excision) of an organ without the possibility of recovery zamechatelnogo rectal apparatus.
Modern surgical techniques allow organ-preserving microsurgery by colono — rectoscopy, but their capabilities are limited to only the first stage of the disease. During germination of the tumor in the muscle layer of the intestine without radical treatment is not enough. Given that the first stage of colorectal cancer is often asymptomatic, few patients fall into this period in the field of view of the doctor, so invasive treatment is significantly inferior to the frequency of usual transactions.
The colostomy is quite common in patients with colorectal cancer. Unnatural back pass is displayed on the anterior abdominal wall or in the area of the perineum. If the location of the tumor allows you to keep the rectal channel, then create a temporary colostomy until the stabilization of the patient. When will be the possible re-operation — a colostomy close and restore continuity of the bowel.
With advanced forms of disease, intestinal obstruction as the result of inoperable cancer, for whom further surgical treatment a colostomy is intended to provide for the removal of feces out, but she will not be able to be closed, and the patient will have to live with it constantly.
Palliative treatment aims to alleviate the condition of patients who are not subject to radical surgery because of the neglect of cancer and severe General condition. As a palliative method is used, the imposition of a permanent colostomy, so the stool is moving to bypass the tumor site. The tumor itself is not removed because of the inability to distinguish it from the surrounding tissues, massively germinated it, and in connection with active metastasis. Palliative colostomy facilitates not only the removal of feces out, but a significant reduction in pain and suspend the growth of neoplasia that stops injury to the intestinal contents.
Surgery on the large intestines require an adequate preparation of the body (cleansing from content), management of shock, antibiotics, infusion therapy. The postoperative period is complicated, require the patient’s endurance and patience.
After the intervention with the formation of colostomy patients need to follow a diet excluding irritant foods, meats, sodas, cakes, fresh fruits and vegetables and much more. Hygiene is very important area of the exit of the intestine on the abdominal wall, to prevent the development of infectious-inflammatory complications.
Chemotherapy and radiation for cancer of the colon are complementary. The most commonly prescribed drugs is considered to be 5-fluorouracil and leucovorin, but since the beginning of this century, a list of updated effective chemotherapeutic agents — oxaliplatin, tomudex, Avastin (targeted therapy drug) that is used as monotherapy or in combination with each other.
Irradiation can be carried out before surgery — a short course for five days or in combination with chemotherapy for one and a half months during germination of the tumor to surrounding tissues. Preoperative radiation therapy is able to reduce tumor volume and to reduce the likelihood of metastasis.
The presence of isolated liver metastases is not always is the reason for the failure of the operation. On the contrary, if it is possible to remove the primary lesion, the surgeons will go for it, and the metastasis or subjected to irradiation, either resolve quickly, if it takes more than one lobe of the liver.
The prognosis of colorectal cancer depends on how quickly the patient gets to the oncologist and how soon it will be carried out the appropriate treatment. To achieve good results allows screening of the disease, so in any case can not neglect the visits to the specialists those people who have a particularly high risk of colonic localization.
Overall, colorectal cancer occurs most favorably to many other forms of cancer. Timely diagnosis and treatment provide an increased five-year survival rate to 80%, but in the second stage of the disease, this figure is reduced to 40-70%, and the metastasis of tumors the chances of survival are only every tenth patient.
To prevent the recurrence of the tumor and early detection of possible metastases, patients should be under the clear control of the oncologist, especially the first two years after surgery when the risk of relapse is highest. Shown studies specific tumor markers, colonoscopy, CT scan, ultrasound, and the doctor should be twice a year the first two years after surgery and annually next 3-5 years.