Adenocarcinoma of the lung

Lung adenocarcinoma is considered one of the most common forms of non-small cell lung cancer. It accounts for approximately 40% of diagnosed malignant lung tumors. It is thought to originate in cellular large bronchial structures, but when detected, it is defined as a peripheral lung cancer with an asymptomatic course.

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Causes of Lung Adenocarcinoma

According to statistics, the disease is most often detected in male patients. This can be explained by the specifics of professional activity (work in hazardous production, inhalation of chemical and toxic substances) and a greater tendency to bad habits. In female patients, only certain types of the disease are more often detected - for example, the bronchopulmonary form of adenocarcinoma.

Predisposing factors for tumor formation are considered to be:

• long history of smoking (there is evidence that daily inhalation of tar and nicotine increases the risk of developing tumors by 20-30 times);
• alcoholism;
• environmental characteristics of the area of residence (large industrial facilities located nearby, highways, as well as unsatisfactory indicators of water, atmosphere, soil);
• nutritional errors (increased consumption of carcinogens – processed foods, fast food, fat, fried foods);
• prolonged exposure to areas with polluted air (dust, soot, etc.);
• work related to the production and use of asbestos;
• regular exposure of the lungs to radon, which is associated with the peculiarities of the geographical location;
• radioactive lung damage;
• chronic infectious and viral lung diseases;
• hereditary predisposition.

Most diagnoses of lung adenocarcinoma are made in patients over 60 years of age, so age can also be considered a predisposing factor for the disease.

Also, a secondary cause of the development of the disease can be considered the uncontrolled long-term use of hormonal medications for the treatment of other pathologies in the body.

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Symptoms of Lung Adenocarcinoma

Unfortunately, malignant diseases in most cases do not reveal themselves with any specific symptoms, and lung adenocarcinoma is no exception.

Non-specific signs of oncology include the following:

• decreased or disappearance of appetite;
• general weakness, fatigue, decreased performance;
• drowsy state;
• weight loss;
• progressive anemia.

Later, the symptoms increase, intensify, and new signs appear:

• cough without cause, often with a small amount of sputum;
• shortness of breath during physical activity, and eventually at rest;
• pain and discomfort behind the breastbone;
• enlarged lymph nodes under the jaw, under the arms, etc.;
• slight increase in body temperature;
• frequently recurring lung diseases that are extremely difficult to treat.

If metastases develop – daughter cells of the tumor that spread throughout the body – then the symptoms will depend on which specific organ the metastasis occurs in.

Stages of lung adenocarcinoma

The effectiveness of therapeutic measures directly depends on the spread of the disease throughout the body. On this basis, 4 stages of the tumor process are distinguished:

• in the first stage, tissue malignancy does not leave the lung;
• in the second stage, the tumor is small, up to 60 mm, but metastases penetrate into the lymph nodes;
• in the third stage, the tumor completely covers the entire pulmonary lobe, metastases are present in the lymph nodes;
• In the fourth stage, damage to the second lung is observed, and metastases are also found in distant organs.

Due to the scarcity of symptoms, stage 4 lung adenocarcinoma is most often detected. However, this pathology can also be successfully treated with modern methods.

Diagnosis of lung adenocarcinoma

Timely diagnosis of malignant neoplasms makes it possible to make treatment more effective, and in oncology this is a very important point. Of course, much depends on the patient himself, who must seek help in time.

To identify a tumor or clarify the diagnosis, the following diagnostic methods are used:

• Chest X-ray is one of the most popular procedures for detecting malignant tumors in the lungs. Tumors are often discovered by chance, for example, during preventive fluorography.
• Computer and magnetic resonance imaging are considered the most modern methods of obtaining information, when the doctor can examine and evaluate the condition of the respiratory system from different angles. This gives the most complete picture of the pathology, with the scale of the neoplasm, spread and metastasis.
• Ultrasound examination is also the number 1 procedure for diagnosing the disease, but its information content in oncology is somewhat overstated.
• Bronchoscopic examination is performed using a special device – an endoscope. The device consists of an elastic fiber-optic tube equipped with a video device and a lighting device. The tube is inserted intratracheally and helps to examine the internal condition of the trachea with the image output to the monitor.
• A blood test for tumor markers indicates the presence of malignant diseases in the body.
• Biopsy is a very important and fundamental study, without which it is difficult to imagine modern oncology. The essence of the method is to take an element of the affected tissue with its subsequent examination. The sample taken can accurately determine the malignancy of the process. The material for analysis is taken simultaneously with a bronchoscopy, or using a transthoracic puncture (which is less desirable and is performed only as a last resort).

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Differentiation of lung adenocarcinoma

Cancerous tumors can differ in various characteristics and parameters, so they are often divided into certain types, species and subspecies.

For example, several categories of differentiation are used according to the distinctive features of malignant cells from healthy ones to tumors. By the way, highly differentiated and normal cellular structures are practically no different.

The term "highly differentiated lung adenocarcinoma" explains the fact that intracellular transformation consists only of a change in the size of the cell nucleus - its elongation is observed. This suggests that this form of the disease does not manifest itself with any symptoms for a long time until it grows to a certain size. Non-specific signs may certainly be present - this is general weakness, apathy, loss of interest in food, weight loss, erythrocytopenia.

Highly differentiated lung adenocarcinoma is found in 60% of all cases of malignant pulmonary lesions, most often in male patients. This pathology may appear as a nodule or a large tumor. It may occur in an acinar form (with a predominantly glandular structure) or in a papillary form (with a papillary structure). Both types of progression tend to increase mucus production.

As we have already said above, the disease does not manifest itself at first. The first signs appear somewhat later:

• the release of a large amount of sputum, possibly with particles of pus or blood;
• coughing fits, increased temperature (not responding to conventional antipyretic drugs);
• shortness of breath, both during exertion and at rest.

Moderately differentiated adenocarcinoma of the lung resembles a highly differentiated disease in the nature of the process. However, in this case there is a pronounced change in the cellular structures. Now they are relatively easy to distinguish from normal ones, since the number of cells with an atypical structure and those undergoing the division phase is steadily increasing, and it is impossible not to notice them.

In addition, moderately differentiated adenocarcinoma is more severe than others, with a high risk of developing concomitant diseases and consequences. This form of tumor is prone to metastasis, mainly to the lymph flow and to the nearest lymph nodes. Interestingly, in patients under 30 years of age, widespread metastases in lung adenocarcinoma are practically not observed.

Low-differentiated lung adenocarcinoma is characterized by primitive cellular development. Such structures are difficult to compare with any tissues of the body, so it is difficult to assess the structure and mechanism of development of this tumor. However, low-differentiated neoplasm has the highest degree of malignancy. The tumor grows very quickly and can spread throughout the body already in the initial period of its development. Of course, this form of adenocarcinoma is considered the most unfavorable, regardless of the stage of growth.

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Treatment of lung adenocarcinoma

Treatment for lung adenocarcinoma may include surgical removal of the tumor, chemotherapy, and radiation. Most often, these therapeutic methods are used in combination - the treatment regimen is determined by an oncologist based on the results of the patient's tests and examinations.

As with other malignancies, the goal of treatment is to completely remove the tumor or, if this is not possible, to prolong the patient's life by alleviating his or her suffering.

Surgical intervention is mandatory in stages I and II of adenocarcinoma, that is, in approximately 10-30% of cases. If the process of metastasis spreading to distant organs has already begun, then one can no longer rely on surgery alone. In addition, surgical intervention may be impossible if the malignant tumor is located close to the trachea, or the patient is diagnosed with severe heart disease.

The type of intervention on the lungs is selected depending on the size and location of the neoplasm. For example, the surgeon can remove a section of the pulmonary lobe, the entire lobe, or one lung entirely. At the same time, the lymph nodes affected by the process are removed.

The rehabilitation period for postoperative patients is not easy; patients require careful care, possibly for several months. At first, those operated on experience breathing difficulties, shortness of breath, and chest pain. Elderly patients require longer rehabilitation.

• Radiation therapy is used before or after surgery. The essence of irradiation is the use of special rays that can destroy cancer cells. In most cases, radiation therapy is combined with surgery and drug therapy.

Brachytherapy may also be prescribed instead of rays. This method is a type of radiation therapy, when a substance emitting radiation is placed directly to the affected organ in the form of granules. A huge advantage of this method is that the radiation does not affect the tumor from the outside, that is, it does not have to overcome layers of healthy tissue. Due to this, brachytherapy has much fewer side effects and complications.

Radiation therapy may be used if the patient refuses surgery for some reason, or if surgery becomes impossible or pointless. Side effects after radiation therapy include a feeling of constant weakness, fatigue, increased susceptibility to infectious diseases, and impaired blood clotting.

Chemotherapy for lung adenocarcinoma can stop the development of malignant cells, prevent their division and cause their death. More than sixty types of chemotherapy drugs are known. The most famous of them are the following:

• Cisplatin
• Carboplatin
• Gemcitabine
• Vinorelbine
• Paclitaxel
• Docetaxel.

Most often, such drugs are taken not separately, but in combination with each other. Medicines are prescribed both in tablet form and as intravenous injections. Calculating doses during chemotherapy is strictly a doctor's decision, since it is quite difficult to determine the exact amount of the drug: if the dose is too low, the treatment will become ineffective, and excessive doses are fraught with severe toxicity and the appearance of pronounced side effects. Usually, the dose is calculated based on the value of the PPT - the surface area of the patient's body. PPT is calculated individually using a specially derived formula, where the key indicators are the patient's body weight and height.

Another method of dosing may be to determine the amount of chemotherapy in the blood plasma over a certain period of time, with subsequent dose adjustment for optimal action. This allows one to calculate the minimum toxic effect of the drug against the background of effective tumor treatment.

The course of drug treatment usually lasts several days. At the end of the course, the patient is given a break to recover and relieve symptoms of intoxication, after which the treatment is resumed. The total number of procedures is calculated individually.

It is known that chemotherapy drugs often cause side effects, although doctors assure that such manifestations can be controlled. What side effects are we talking about?

• Increased sensitivity of the body to infections - this condition usually manifests itself a week after the end of the course, reaching a maximum after 2 weeks. After this, immunity begins to recover and is normalized before the resumption of treatment. This process is monitored by periodically taking blood for analysis: if the blood picture is unsatisfactory, then further procedures may be postponed.
• The appearance of hematomas and bleeding is the result of deterioration of blood clotting due to a decrease in the level of platelets. This condition is quite dangerous, since tissue bleeding can develop into full-fledged bleeding, which requires immediate medical attention.
• Anemia is a very common side effect. Anemia occurs due to a decrease in the level of red blood cells and, consequently, hemoglobin, which manifests itself as a feeling of constant fatigue, weakness and apathy.
• Attacks of nausea and vomiting may begin unexpectedly. In such cases, it is necessary to consult a doctor who will prescribe medications to eliminate this problem.
• Stomatitis and gum pain are eliminated by regular mouth rinses. To avoid unnecessary mechanical trauma to the oral mucosa, you should eat pureed food and drink enough high-calorie liquid.
• Hair loss is a common and very unpleasant side effect, especially for female patients. You can ask your doctor to change the drug that causes this effect, or resign yourself to wearing a wig or scarf. In most cases, hair growth is restored within a few months after the last course of treatment.

Treatment of adenocarcinoma does not always affect patients in the same way: one patient reacts painfully to radiation, while for another these procedures do not cause any negative consequences. Someone suffers from the side effects of drugs, while for someone they are optimally suited. This is why doctors insist on an individual approach to treatment: it is important to listen to the doctor and follow all his recommendations.

Prevention of lung adenocarcinoma

To reduce the likelihood of developing lung adenocarcinoma, you must adhere to the following rules:

• Quit smoking. It has been proven that the more cigarettes a person smokes per day, the greater their chances of developing lung cancer.
• Avoid prolonged stays in dusty rooms, as well as in enterprises where the air contains particles of harmful chemicals, carcinogenic and toxic substances. Workers in hazardous industries must take measures to protect their respiratory tract: wear respirators, gas masks, special suits. Air filtering devices, smoke and dust collectors, waste storage facilities, etc. must be installed in the workshops and premises of such enterprises.
• Treat acute and chronic respiratory diseases promptly, periodically conduct preventive examinations and studies of the respiratory organs. This especially applies to those people who have had cases of malignant lung disease in their family, as well as people living in unfavorable environmental conditions, near large highways, industrial facilities, power plants.
• Avoid contact with potentially dangerous carcinogens, which include arsenic, chromium, various resinous substances, radon, asbestos, nickel. Avoid inhaling these substances and their vapors.

Proper nutrition will also help protect yourself from malignant diseases. Experts have proven that food of predominantly plant origin, a minimum of fried foods, animal fats, salt and hot spices, as well as the exclusion of preservatives and dyes will help reduce the risk of developing oncology in the body as a whole.

Moderate physical activity is also important, as regular natural ventilation of the lungs helps improve blood circulation and accelerate the removal of toxic substances from the body.

Prognosis of lung adenocarcinoma

Survival for lung adenocarcinoma may depend on the type of tumor and its stage of development.

In stage I and II, the prognosis is considered very favorable, especially in terms of five-year survival. Overall survival is between 50 and 70%.

With stage three tumors, approximately 20-25% of patients survive for five years, while in the first year, about half of all patients have a chance.

Stage IV malignancy has the worst prognosis – only 10 out of a hundred patients can survive for five years, although within 10 months this figure can be approximately 50%.

A low-differentiated tumor is characterized by the most aggressive development of all types of adenocarcinoma. Without therapeutic measures, patients may die within 2-4 months after diagnosis. However, such a tumor is considered more sensitive to radiation and drug treatment, so there is no need to delay taking measures. The life expectancy of patients can be increased by using complex treatment, which involves the use of all possible methods.

Lung adenocarcinoma is a serious and complex disease, like any other malignant tumor. However, this disease can be cured. The main thing is not to despair and follow all the recommendations of the attending physician.