The first symptoms, stages and treatment of rectal cancer

What is rectal cancer?

Rectal cancer – this is a tumor degeneration of the cells of the epithelium of the mucous membrane of any of the sections of the rectum, which has all the signs of malignancy and cellular atypia. This means that such a tumor manifests itself with the usual properties of malignant neoplasms, namely: rapid and infiltrative growth with penetration into surrounding tissues, a tendency to metastasize, and frequent relapses after treatment. Modern oncologists combine rectal cancer with colon cancer into one group and call it colorectal cancer. The disease is equally common among men and women in the age range from 40 to 75 years. The prevalence is 16 cases per 100 population per year.

Despite the frequent occurrence, this type of oncological pathology ends with a favorable outcome much more often than other cancerous tumors. This is due to the fact that the anatomical location of the primary tumor in rectal cancer is available for diagnosis in the early stages of development. To detect a tumor, the doctor needs a simple digital examination or an endoscopic examination in the presence of the slightest complaint. In addition, most cases of early stages of rectal cancer (with the exception of low-lying forms) are well amenable to removal by surgery, and are quite sensitive to radiation and chemotherapy.

When planning treatment tactics and making predictions for specific cases of rectal cancer, several of its most important characteristics are guided:

1. Growth zone in the rectum:

   • Rectosigmoid department – a tumor at a height of more than 12 cm from the anus;

   • Upper ampullar – a tumor at a height of 8 to 12 cm from the anus;

   • Medium ampulla – a tumor at a height of 4 to 8 cm from the anus;

   • Lower ampulla – from the dentate line to 4 cm;

   • Anal cancer – the tumor is located within the anus;

2. Type of cancer growth:

   • Exophytic – in the lumen of the rectum in the form of a tumor node;

   • Endophytic – the tumor grows through the wall of the organ and protrudes slightly into its lumen;

   • Infiltrative – cancer, quickly involving in the tumor process all the tissues located around the rectum, in the form of an inflammatory conglomerate;

3. The presence of metastases

   • Damage to the rectal lymph nodes;

   • Metastases in the tissue of the pelvis;

   • Involvement of para-aortic and inguinal lymphatic collectors;

   • Distant metastases in the liver, lungs and other organs;

   • The degree of histological differentiation of a cancerous tumor:

   • Poorly differentiated – grows slowly and rarely metastasizes;

   • Highly differentiated – very quickly shows all the signs of malignancy;

   • Moderately differentiated – occupies an intermediate position between the previous types of cancer.

Life expectancy with rectal cancer

The statistics for rectal cancer are not always optimistic, but they are much better than for other types of cancer:

• Despite the availability of diagnostics, the detection of the disease at stages 1-2 does not exceed 20%. Approximately the same number of patients already have metastases in the lymph nodes and internal organs;

• In most patients (about 60-70%), the disease is detected at stage 3;

• On average, about 5% of patients survive the 60-year milestone after treatment;

• In stage 4 rectal cancer, a five-year survival rate has not been reported. The average life expectancy of such patients is from 3 to 9 months;

• The life expectancy of patients with an established diagnosis of highly located low-grade rectal cancer at stages 1-2 is the highest and is measured in decades;

Symptoms of colorectal cancer

Cancer of the rectum for a long time does not manifest itself with specific symptoms. The situation is aggravated by the fact that when symptoms appear, patients often do not pay attention to them. Indeed, more than 75% of such people have a burdened anamnesis regarding the pathology of the rectum and anal canal (chronic hemorrhoids, paraproctitis and rectal fistulas, anal fissure and itching, proctitis of various origins). Therefore, perceiving the true symptoms of cancer as another exacerbation of their chronic disease, a person seeks help only when the symptoms listed in the table occur.

The first symptoms of rectal cancer

The whole difficulty of early diagnosis of rectal cancer lies in the non-specificity of its first manifestations. Usually these are symptoms that each person periodically observes in himself.

Therefore, with regard to rectal cancer, you should always be alert:

• The primary appearance of any of the symptoms characteristic of this disease and their long-term persistence (weakness, subfebrile temperature, weight loss and appetite, constipation, discomfort in the rectal area);

• Progression of symptoms characteristic of any diseases of the rectum, if they are present in history;

• The appearance of any discharge, especially with blood impurities. Patients with chronic hemorrhoidal bleeding must necessarily note their intensity and the nature of the secreted blood, which changes with rectal cancer;

• The first symptoms of the disease in the form of intestinal obstruction or severe bleeding always indicate the late stages of the tumor process.

Signs of colorectal cancer

The clinical picture of rectal cancer, consisting of complaints and objective signs of the disease, is based on the data given in the table.

Causes of colorectal cancer

The main causes of colorectal cancer include:

• Immune imbalance in the body, in which the immune surveillance cells responsible for the elimination of tissues with signs of cellular atypism are unable to provide antitumor protection. Against this background, defective cells of the rectal epithelium, constantly formed in the process of mucosal renewal, go unnoticed. As a result, their further reproduction in the form of a tumor. This mechanism of colorectal cancer is usually combined with other causative factors;

• Precancerous conditions on the part of the mucous membrane of the rectum and anal canal. These include any chronic diseases of the anorectal zone: hemorrhoids, paraproctitis, rectal fistulas, chronic anal fissure, chronic proctitis and proctosigmoiditis, Crohn’s disease and UC (ulcerative colitis). The start of tumor growth in this case is caused by a violation of the process of normal cell division caused by their long-term damage;

• Single large polyps or polyposis of the colon and rectum. The presence of benign growths of the mucosa in the form of tumor-like thickenings is accompanied by their constant growth. In this case, there is an extremely high risk of malignancy of polyps with their transformation into a cancerous tumor;

• Carcinogens. These include chemicals (nitrates, pesticides, industrial poisons and emissions), ionizing radiation, food (the predominance of meat dishes, fast food, cholesterol and animal fats in the diet), oncogenic viruses. Carcinogenesis is built in such a way that any of the carcinogens causes direct damage to the genetic material of the cells of the rectal mucosa, or affects indirectly through the formation of toxic products of lipid peroxidation. Cells with damaged DNA in the p53 gene locus, which triggers apoptosis (automatic death of a tumor cell), are immortal and multiply in the form of a tumor;

• genetic predisposition. A burdened hereditary history of colorectal cancer is one of the main risk factors for the development of this disease in first-line relatives.

Stages of colorectal cancer

The classification of rectal cancer depending on the stage of the tumor process is based on the following characteristics of the disease:

• The size of the primary tumor;

• The prevalence of the tumor in relation to the intestinal wall and lumen;

• Involvement of adjacent organs in the tumor process;

• The presence of metastases in the lymph nodes;

• The presence of metastases in distant organs.

All of these features are consistent with the TNM classification of rectal cancer. The stage reflects only a combination of different degrees of indices of each of the components of this abbreviation (from the first to the fourth degree, for example – T2N1M0). Isolation of the stage of the disease should be intertwined with the necessary treatment tactics.

	Rectal cancer stage 1 Stage 1 is said to be if the cancer in the form of a tumor or ulcer is small, mobile, and occupies a clearly defined area of ​​the mucous membrane. According to the degree of distribution, it does not penetrate deeper than the submucosal layer. Regional and distant metastases are not detected.
	Rectal cancer stage 2 Stage 2A is determined if the cancerous growth extends to an area from 1/3 to 1/2 of the mucosal circumference, but is located strictly within the intestinal lumen and its wall. There is no metastatic lesion; Stage 2B. The fundamental difference of this stage is that there are already metastases in the regional periintestinal lymph nodes. The primary tumor is similar in size to stage 2A or smaller.
	Rectal cancer stage 3 Stage 3A – the tumor occupies more than half of the circumference of the rectum. The depth of germination is characterized by the involvement in the tumor process of the entire wall of the organ and perirectal tissue. In this case, single metastases are recorded in the lymph nodes of the first order. Stage 3B. Any size and depth of tumor spread. At the same time, multiple metastatic foci are recorded in all rectal lymphatic collectors;
	Rectal cancer stage 4 Stage 4 can be represented either by a tumor of any size in the presence of distant metastases in the internal organs and lymph nodes, or a decaying tumor with destruction of the rectum and germination through the surrounding tissues of the pelvic floor in combination with regional metastases.

Prognosis of the disease

Predicting the outcome of colorectal cancer can be based on the following data:

• Stages of the disease;

• Type and degree of tumor differentiation;

• Age and general condition of the patient;

• The presence of concomitant pathologies;

• Timeliness, adequacy and effectiveness of the treatment.

Depending on this, the prognosis for rectal cancer can be as follows:

• Cancer of the anal canal and lower ampulla of the rectum has the worst prognosis even at stages 1-2, as it requires a disabling operation and often recurs. Such patients are forced to use colostomy bags for life;

• Poorly differentiated tumors always have a much better prognosis than highly differentiated tumors;

• Forecasts for life and recovery are significantly aggravated by advanced age, concomitant diseases and disorders of the general condition of patients. These factors not only limit the possibilities for performing radical surgery, but also accelerate the progression of the tumor process;

• The survival rate of patients who are in a relatively satisfactory general condition with stage 1-2 cancer ranges from 60% to 85%;

• With stage 3 tumors in patients with relatively good health, the survival rate for 5 years after diagnosis, subject to radical treatment, is about 30%;

• With stage 4 cancer, the prognosis for life is unfavorable. Almost all patients die within 6-8 months.

• Refusal of radical treatment of operable forms of cancer of any stage has an unfavorable prognosis and ends in death within a year.

rectal metastases

Most prone to metastasis are cancerous tumors of the rectum with a high degree of cell differentiation. Even their small size does not exclude the presence of distant metastatic foci.

Favorite places for metastasis of such tumors:

• Regional, pelvic and retroperitoneal lymph nodes;

• Liver;

• Lungs and pleura;

• Hollow abdominal organs and peritoneum;

• Brain;

• Flat bones and spine.

Primary distant metastases in 95% of patients appear in the liver. At the same time, it increases its size and thickens, which is manifested by discomfort and heaviness in the right hypochondrium. As new metastases grow and appear, they gradually replace the liver tissue, which disrupts the functional abilities of the liver and is manifested by yellowness of the skin.

The second most common type of distant metastases is considered to be a lesion of the peritoneum, which is called carcinomatosis. As a result of its irritation and impaired functional abilities, ascites is formed with the accumulation of a huge amount of ascitic fluid. Similar changes occur in the pleural cavity in the presence of pleuropulmonary metastasis. At the same time, one- or two-sided hydrothorax is ascertained.

Diagnosis of rectal cancer

Directions and methods for diagnosing rectal cancer can be as follows:

1. Confirmation of the presence of a tumor in the rectum:

   • Digital rectal examination;

   • Sigmoidoscopy. Informative for low-lying crayfish;

   • Fibrocolonoscopy. More appropriate for cancerous lesions of the rectosigma;

   • Irrigoscopy;

   • Determination of oncomarkers of rectal cancer in the blood.

2. Identification of metastases and extent of the tumor:

   • Transabdominal ultrasound examination of the abdomen and pelvis;

   • X-ray examination of the chest organs;

   • TRUS – transrectal pelvic ultrasound;

   • Tomography in the mode of computer or magnetic resonance research.

3. Identification of the histological type of the tumor. Achieved only by biopsy during endoscopic examination with further study of the drug from the biopsy specimen under a microscope;

4. Other research. They include general and biochemical blood tests, gastroscopy, ECG, determination of blood clotting abilities and other data that may be required when drawing up a treatment program.

Treatment of rectal cancer

The localization of rectal cancer is such that it allows the use of all methods used in oncological practice in its treatment. The choice of a specific method or their combination depends on the depth of location and the degree of germination of the tumor, the stage of the process and the general condition of the patient. In any case, surgery is rightfully considered the central method of treatment. But in an isolated version, it can only be used for small low-grade tumors of stage 1-2. In all other cases, an integrated approach is shown.

An integrated approach includes:

• Contact and remote radiation therapy in the pre- and postoperative period;

• Surgery;

• Polychemotherapy.

Features and possibilities of surgical treatment

The choice of a specific type of operation is carried out depending on the height of the location of the tumor focus.

Surgical tactics may be as follows:

1. Any forms of cancer at the height of intestinal obstruction require the removal of an unloading transversostomy. After stabilization of the patient’s condition, a radical operation is performed to remove the tumor;

2. Cancer of the rectosigmoid flexure. An obstructive resection of the rectum is performed with the removal of an unnatural anus in the form of a flat sigmostoma. The procedure is better known as the “Hartmann operation”;

3. Cancer of the upper ampulla, sometimes the middle ampulla. Anterior resection of the rectum with lymph node dissection and removal of the pelvic tissue is shown. Intestinal continuity is restored through a primary anastomosis. Sometimes an unloading preventive transversostomy is applied;

4. Cancer of the middle and lower ampullarongo of the rectum. Peritoneal-anal extirpation of the rectum is performed. In this case, almost the entire rectum with a tumor is removed, leaving only the sphincter apparatus. By bringing down the sigmoid colon and fixing it to the anal sphincter, the possibility of natural defecation is restored;

5. Cancer of the anorectal region and any tumor with damage to the sphincter. Performed peritoneal-perineal extirpation of the rectum (Kenyu-Miles operation). In this case, the entire rectum with the closing apparatus and lymph nodes is removed. An unnatural anus is removed, with which the patient remains for life.

Chemotherapy for colorectal cancer

Chemotherapy plays an important role in the prevention of rectal cancer recurrence. This method of treatment involves intravenous infusions of combinations of several antitumor chemotherapy drugs, to which colorectal cancer tumor cells are sensitive. Among these drugs: 5-fluorouracil, oxaliplatin, leucovorin. Chemotherapy using these agents is indicated as the only treatment for tumor resection, or in combination with surgery. If multiple metastases in the lymph nodes or single metastatic foci in the liver were determined at the time of the operation, chemotherapy for rectal cancer is carried out in periodic courses for a long time.

Diet for rectal cancer

Proper nutrition in rectal cancer should be given increased attention. The diet should be sufficiently nutritious and balanced in qualitative and quantitative terms, and not cause irritation of the intestines. Therefore, spicy and fatty dishes, spices, alcohol, smoked meats, marinades and canned food are excluded from the menu. They are replaced with fresh vegetable salads, low-fat fish and dietary meat, nuts, sour-milk products. It is very important to properly organize the diet in relation to the distribution of the daily volume of the diet between meals.

An indicative weekly menu for a patient diagnosed with rectal cancer is shown in the table:

Prevention of rectal cancer

It is not easy to prevent colorectal cancer. This is due to the fact that it is not always possible to influence all its causes.

But it is in the power of each person to eradicate those risk factors, the presence of which increases the likelihood of developing this disease tenfold, or to do everything so that the disease that has arisen is detected as early as possible:

• Timely treat chronic diseases of the rectum and anal canal (hemorrhoids, fissures, fistulas, etc.);

• Fight constipation;

• Refuse excessive consumption of animal fats, fast food and enrich the diet with vegetable oils;

• Minimize contact with hazardous chemicals;

• Get regular checkups once or twice a year.

Of course, all these activities do not guarantee 100% protection against rectal cancer, but they significantly reduce the risk of its occurrence.