Colon cancer - a pathological cancer of a tumor formed from the epithelial layer of mucous membrane that lines the inside of the entire colon and is divided into a straight line, colon and cecum with characteristicfor him localization of tumor process.
cancer that affects the large intestine, approximately 5% of different malignancies and is much more common among men 50 to 60 years.Some types of diseases, including ulcerative colitis nonspecific etiology, diffuse polyposis and adenomas are considered in the development of the underlying pathology of the intestine as the predisposing factors in the appearance of tumors.Therefore, 100% diffuse polyposis is the cause of malignancy.But colorectal carcinomas are most common in developed countries and this is mainly due to increased consumption in food of animal fat and meat, especially pork and beef, and a reduced amount of fat.Conversely, reduced cases of colon cancer in people who consume a vegetarian diet.
Colon cancer causes
Basically the main reason for the development of colon cancer is the effect of the carcinogenic nature of substances that are formed in the intestinal contents of the food remains under the influence of various bacteria.It is in the stool is a huge amount of bacterial flora, which is calculated billionaire content in one gram of the substance.Many enzymes that are released by microorganisms, are involved in metabolic processes and bacterial action of amino acids released ammonia formed phenols, nitrosamines, primary bile acids are converted into secondary shapes.Already it is proven that these secondary derivatives have an activating, carcinogenic and mutagenic.And for the development of colon cancer (colon), they are a fundamental part in contrast to the toxic metabolites of amino acids.The process of conversion into secondary bile acids, acid occurs under the influence of a special enzyme, which is produced by bacteria of the intestinal flora.Activity holanoin 7-degidroksilazy increases with elevated levels of bile acids.Their concentration depends on the type of power supply, so it increases with each meal rich in fats and proteins, raising the percentage increase in morbidity.
In addition, factors in the development of colon cancer is considered to be precancerous lesions, which includes polyps.They are formed from the expanding epithelia and connective tissue, representing a small papillae or circular formations that rise above the mucosal surface and are a product of inflammation, presenting a benign tumor.Hyperplastic polyps are much more common etiology adenomatous group, but their malignancy rather questionable.Therefore adenomatous polyps are pre-cancerous abnormalities of the nature of the large intestine.They appear in the form of rounded formations of pink with a red shade, have a soft texture and is located on a narrow leg with a velvety surface.These polyps are mainly in the rectum, and then can be localized in the sigmoid, cecum and descending part of the colon.These villous polyps with significant amounts become cancerous.Severe dysplasia increases the development of colon cancer, even in the independence of these dimensions.Suschestvuyut polyps single and multiple location, and even the nature of diffuse polyposis.
Colon cancer can develop in 100% with family history.In addition, this disease is hereditary and occurs quite early malignancy.
Colon cancer symptoms
Clinical symptoms of colon cancer is conventionally divided into two halves of the colon: right and left.No specific anatomical clear separation of these parts.Basically tumor relating to the right side, are located in a blind section of the large intestine in the uplink part and the right bending.In this case, the right side of the symptoms of tumors of the colon characterized by five key features that caused by intoxication, and compression, and for the left half - obturation manifestations in a tubular organ and tumor destruction.
colon cancer observed symptoms are varied and numerous, united in a certain group of syndromes, of which emit some clinical forms.Such as a tumor, obstructive, dyspeptic, psevdovospalitelnaya, enterokolicheskaya and toxic-anemic.
colon cancer in the right half manifested by pain, the presence of palpable tumors, loss of appetite, general weakness and anemia.Almost 90% of patients complain of pain, which is the primary symptom of the disease, and there is basically a right abdomen without specific localization.Pain appear different character and intensity.Typically, the pain is dull and aching with not very intense and constant action, for which is characteristic of a tumor or inflammation of her sprouting in other somatic organs.Sometimes it is expressed by short sharp bouts resembling attacks of cholecystitis or acute appendicitis.The pain caused by the changes in the bauginievoy flap.In this case, the faeces that are in the blind section colon, are thrown into the iliac section and its reduction of spasms and cause the appearance of pain.
About 70% of patients with colon cancer suffer hypochromic anemia, which is also the first sign of a tumor disease.Thus not anemia associated with bleeding in the intestine.Laboratory diagnosis is not always found in the intestinal contents, with right-sided tumors, hidden or visible blood.Therefore, many clinicians degree of anemia associated more with intoxication as a result of the suction of infected feces and tumor degradation products.
much rarer among clinical symptoms characteristic of colon cancer, identified as a manifestation of lack of appetite, general malaise and fatigue.Sometimes they appear very early, but patients are not in a hurry to seek the advice of a specialist.It is important to know that weight loss for the pathology of the colon is not a characteristic feature, and is extremely rare.
One of the important symptoms of colon cancer is considered to be probing the tumor.Patients rarely (7% of cases) fails to detect a tumor itself, but already at the time of admission, palpation, it is diagnosed in 75% of patients.When exophytic growth, unlike endophytic, certain tumors passes much easier.During palpation of the tumor it is felt in the form of dense or plotnoelasticheskoy consistency with the bumpy surface.If there are no inflammatory complications, the tumor does not cause pain and a little sensitive probing with precise contours and rounded edges.The neoplasm may shift depending on the movements of the affected parts of the colon and of the proliferation of colon cancer in other tissues.A feature of the mobility of the tumors in the cross sections of the large intestine, with lower mobility in the blind.For tumors of the right bend and ascending colon are characterized by low mobility.
For percussion, sound is heard over the tumor dull, and at the rear wall lesions, especially the blind gut department, the sound may not be determined.
there is also a very rare clinical signs of colon cancer.These include belching, nausea, epigastric bloating, vomiting (in rare cases), and the feeling of an unpleasant taste in the mouth.This complex is symptomatic evidence of the dysfunction of the stomach, and was named the syndrome of intestinal discomfort.
nearly five patients among one, colon cancer right causes an increase in temperature.This fever can last for a long time, while achieving high performance.Sometimes the temperature is considered to be the first symptom of the tumor.And at the protracted fever of unknown etiology, it is necessary to investigate the gut, using X-rays.
clinical picture of cancer left colon is completely different from all of these symptoms.With existing tumors, there is difficulty in the distribution of feces in the intestines, which has varying degrees.Almost half of the patients complained of persistent constipation, which are difficult to treat with medicines and diet, and may be accompanied by weight in the intestines, bloating and rumbling.After his release in copious amounts of gases and feces, all of these features for some time pass.
Diarrhea for this section of the large intestine in colon cancer are not typical, but the change of diarrhea with constipation, which is a rare phenomenon may indicate malignancy.This is related to the intensity of the fermentation which occurs after a delay of a chair, and then the liquid is released into the intestinal lumen and the dilution of feces, and then they are accumulated over the restriction.Thus, at first it appears after a delay stool, diarrhea, and then - constipation.
After a significant narrowing of the lumen of the intestine occurs its obstruction, chronic etiology, manifested by pain of short-term nature, repeated periods of detention gas and stool, bloating and transient pain.In some cases, intestinal obstruction in the form of pathology is developing rapidly with the emergence of severe abdominal pain in the form of labor, which is characterized by the sudden arrest of the chair and gases, and pain with symptom Shchetkina.
ileus tend to develop large tumors, which narrows the lumen of the intestine.However, acute or chronic obstruction, not a symptom in which it is impossible to conduct the operation.
characteristic of colon cancer on the left side of the intestine with the pathology considered impurities in the stool.Impurities are characterized by blood from injuries, which are formed as a result of the passage of stool through the solid portion narrowed by the tumor.It is often found in the study of occult blood in the stool scatology.In patients with tumor pathology of the colon in the analysis determined a small amount of mucus, and in some inflammatory changes - impurities of pus.
Many patients have epigastric bloating.Sometimes this is a result of accumulation of gases in the cross section of the colon.Very few clinical signs of cancer of the left half is a general weakness, intestinal discomfort, poor appetite, anemia, and weight loss, so they can not argue about the presence of a tumor.
colon cancer right half is a gradual progressive disease, and increases the number and severity of symptomatic picture.The distal parts of the disease occurs with a sudden onset of intestinal obstruction.
addition, each manifestation of symptoms of colon cancer has its own peculiarities in the course of the disease.
When toxic-anemic form of colon cancer observed symptoms such as malaise, weakness, fatigue, rise in temperature, change in skin as pale and progression of anemia.This form of cancer develops in the blind department colon and ascending colon.
For enterokoliticheskoy form of colon cancer is characterized by a full range of symptoms of bowel disorders in which the identified long constipation, diarrhea, flatulence, rumbling stomach, the appearance of pus and bleeding of mucous secretions from the colon.
for diarrheal form of colon cancer - heaviness in the epigastric region, nausea, belching, loss of appetite, recurrent vomiting, bloating and abdominal pain.
for obstructive form of colon cancer characterized by the early occurrence of intestinal obstruction.First and characteristic blunt abdominal pain, passing in aching pain without specific localization.Then they become stronger appearing attacks which are associated with retention of the chair and gases.Later, these attacks are becoming more frequent, they become longer and formed a chronic form of intestinal obstruction.After some attack comes absolute obstructive ileus.
When psevdovospalitelnoy form of colon cancer characteristic symptoms resemble the process of inflammation of the abdominal cavity.In this form, marked abdominal pain attacks, irritated and tense the muscles abdominal wall, fever, leukocytosis and increases in ESR increases.
During the development of atypical forms palpable tumor with few clinical symptoms.
When diagnosing colon cancer the main point is to establish the stage of the disease, because of this in the future depends on the patient's treatment.To detect colon cancer using different diagnostic and laboratory tests, which are determined as a result of all the signs that correspond to a particular stage of the disease.In attention should always be taken by the patients themselves and feel.
have colon cancer classification is divided into four stages, which depend on the behavior of cancer in the body.
first stage of colon cancer - is when the tumor occupies less than half intestinal circumference is limited only defeat mucosal and submucosal layers, with no spread to lymph nodes.
second stage of colon cancer - this is when the disease process is localized to more than half the circumference of the intestinal or distributed in the muscular layer with a single penetration of the lymph nodes.
third stage of colon cancer - tumor occupies more than half the circumference of the intestine, grows in the serosa, or gives metastases to regional lymph nodes.
fourth stage of colon cancer - this is when the tumor occupies a vast surface that extends to nearby tissue and organs, and gives distant metastases.
In medical practice, use two classification stages of colon cancer.In 1932 he was offered one of them, and in 1997 - the second (TNM).In the first classification of the disease is divided into stages: A, B, C, D.
A step - becoming the tumor is not affecting the layers below submucosal.
In stage - during germination of all layers of the intestine.
On stage - at various sizes with additional tumor metastases to the regional lymph nodes.
D stage - in the diagnosis of distant metastases.
But most informative at the moment is considered the classification of colon cancer, which is proposed in 1997, as it reveals all the indicators in each category of the tumor, and this makes it possible to more accurately describe it.This classification (TNM) involves three stages on the title.For each stage of their characteristic markers that define the status of the tumor.
Colon cancer treatment
only and radical treatment for colon cancer is surgery.Chemotherapy and radiation exposure have the effect of palliative effects, and is used mainly as a complementary therapy to surgery.
beam radiation for colon cancer may be performed as an independent therapy as a palliative treatment for patients with locally advanced colon cancer in the rectum, and in parallel with the radical surgery in the second and third stages of the disease.In this case, use kilocuritherapy.As an independent treatment to palliative care, it is assigned to small doses (amounting to 50-60 Gy).
Today, treatment of colon cancer conducted shaded courses of therapy.During radiotherapy for locally advanced cancer of the colon is sometimes possible to conduct radical surgery.With combination therapy beam radiation do before surgery increased dose (total - 20-30 Gy).Then, two days later proceed to resection of the tumor.