LUNG CANCER Who is at risk? Why and How? Diagnosis Staging Treatment After Treatment

Lungs, which are part of the respiratory system, are a couple of spongy, conical organs. The right lung consisting of three parts (lobes) is slightly larger than the left one consisting of two lobes. When we inhale, lungs take in the oxygen needed by our cells to live and to carry on with normal functions.

When we exhale, lungs remove carbon dioxide that is a waste material of body cells. Cancers originating in lungs are classified into two essential groups on the basis of their views under the microscope, namely non-small cell lung cancers (NSCLC) and small cell lung cancers (SCLC). Each lung cancer type tends to grow and proliferate in a different manner and therefore must be treated differently. Non-small cell lung cancer is more prevalent than small cell lung cancer and is slower in growth and proliferation. Small cell lung cancer has three main types named according to the type of cell where the cancer originates: squamous cell cancer (also called as epidermoid cancer), adenocarcinoma and large cell cancer. Small cell lung cancer is sometimes known as oat cell cancer and is less prevalent that the other type. This type of lung cancer grows more rapidly and tends to spread to other organs more frequently.

Who is at risk?

Researches have so far come up with several reasons for lung cancer, most of which are associated with tobacco use.

Smoking: Smoking causes lung cancer. Harmful substances in tobacco with known carcinogen effects cause damage to the lung cells. Those damaged cells may in time become cancerous. Factors influencing the development of lung cancer in smokers are starting age and period of smoking, the number of cigarettes smoked daily and the extent to which the smoker inhales the smoke. Quitting smoking considerably reduces the risk of lung cancer.

Cigars and pipes: Cigar and pipe smokers have a higher risk of developing lung cancer than non-smokers. The number of years during which the person has smoked, the number of cigars or pipes smoked daily and the extent of inhalation affect the risk of cancer development. Even cigar or pipe smokers who do not inhale are under an increased risk of developing lung, mouth or other cancers.

Environmental (passive) smoking: Exposure to environmental tobacco smoking due to smoking of other people increases the risk of developing lung cancer.

Radon: Radon is an invisible, colorless and odorless radioactive gas naturally occurring in soil and rocks. It may lead to lung cancer and cause damage to lungs. Miners may be exposed to radon and radon may be present in houses at some regions. Smoking increases the risk of lung cancer development further due to radon exposure. Tests measuring the level of radon at houses are available.

Asbestos: Asbestos, naturally occurring as fibers, is the name of a group of minerals used in particular industries. Asbestos fibers tend to break apart easily. These particles may float in air and cling to clothing. When inhaled, these particles settle in lungs and increase the risk of lung cancer by damaging the cells. Studies revealed that the risk of developing lung cancer in workers exposed to large amounts of asbestos is 3-4 times higher than those not exposed to asbestos. This exposure is common in several branches of industry such as shipbuilding, asbestos mining and production, isolation works and brake repairs etc. The risk of lung cancer is even higher in asbestos workers who are also smokers. Workers exposed to asbestos must use protective equipment made available by employers and follow the recommended work and safety rules.

Air pollution: Investigators established a relation between lung cancer and some air polluting waste such as diesel fuel products and other fossil fuels. Nevertheless, further studies must be conducted to reveal this relation more clearly.

Lung Disease: Some lung diseases (such as tuberculosis) increase the risk of lung cancer that tends to develop in parts of the lung damaged by tuberculosis.

Personal History: Those who have previously had lung cancer are under a greater risk of developing lung cancer for a second time than those who have never contracted this type of cancer. It is a proven fact that quitting smoking after contracting lung cancer may prevent lung cancer from developing for a second time.

The best way of protecting from lung cancer is to quit smoking or to never smoke. The earlier a person quits smoking the better. Even if you have been smoking for a long time, it is never too late to reap the benefit of quitting smoking.

Why and How?

The following signs may be associated with lung cancer or other conditions. It is important to have them evaluated by a physician. The main signs and symptoms of lung cancer are:

  • Continuous unremitting and worsening cough,
  • Constant chest pain,
  • Bloody phlegm,
  • Shortness of breath, wheezing or hoarseness,
  • Lung infection or bronchitis with recurring problems,
  • Swelling in the face or neck,
  • Lack of appetite or weight loss,
  • Fatigue.

Diagnosis

To find the reason for these symptoms, the physician must evaluate the person’s medical history, smoking history, exposure to environmental and vocational substances and familial history of cancer; carry out a physical examination and request lung radiography and other laboratory tests. If lung cancer is suspected, phlegm cytology (microscopic examination of cells in phlegm obtained by means of profound cough) is a simple test beneficial for diagnostic purposes. In order to verify the diagnosis of lung cancer, lung tissue must be examined. A biopsy (during which a small piece of tissue obtained from the lung is investigated under a microscope by a pathologist) may reveal whether the person has lung cancer. Various methods are available to obtain this piece of tissue.

Bronchoscopy: The physician uses a bronchoscope (a thin tube with light) inserted through the mouth or nose to examine the respiratory tract, or to collect cell or small tissue samples.

Needle Aspiration: This procedure involves the collection of a small piece of tissue by means of a needle inserted into the tumor via the patient’s chest.

Thoracentesis: This is the procedure of collecting a sample from the fluid surrounding the lungs with the purpose of checking cancerous cells.

Thoracotomy: Same patients may need to undergo open chest surgery to diagnose lung cancer. This is a major procedure that must be carried out in a hospital setting.

Mediastinoscopy / Mediastinotomy: Mediastinoscopy may be helpful in showing whether the cancer has proliferated to the lymph nodes in the chest. The center of the chest (mediastinum) and any lymph nodes in the vicinity are examined with an instrument called scope that is equipped with a light. The scope is inserted via a small incision at the throat during mediastinoscopy, whereas the incision is made at the chest during mediastinotomy. The scope is also used to collect a small piece of tissue during both procedures that are performed with general anesthesia.

Staging

After cancer is diagnosed, physicians will wish to establish the condition’s stage (dissemination). Staging is carried out to find out whether the cancer has spread and, if so, to which parts of the body. Lung cancer commonly metastasizes to the brain or bones. Knowing about the cancer’s stage will help the physician make a proper treatment plan.

Treatment

Treatment depends on numerous factors such as the type (non-small cell and small cell lung cancer), extent, location of the cancer, the spread of the tumor and the patient’s overall health status. Many different treatments and treatment combinations may be used to keep lung cancer under control and/or to enhance the quality of life by reducing the symptoms.

Surgery is performed to remove the cancerous cells. The type of surgical procedure to be carried out by the physician depends on the tumor’s location on the lung. The surgical operation conducted to remove only a small part of the lung is called “partial resection”. If the surgeon removes one lobe completely, this procedure is called “lobectomy”. Pneumonectomy is the removal of one of the lungs entirely. Some tumors are not operable due to their size or location. Some patients may not undergo surgery due to concurrent health issues.

Chemotherapy is the treatment of cancer by using anti-cancer drugs to kill cancerous cells in the body. Even after the tumor is removed from lungs, cancerous cells may be present in surrounding tissues or any other part of the body. Chemotherapy may be applied to keep the growth of the cancer under control or to eliminate symptoms.

Radiation therapy, also known as radiotherapy, involves the use of high-energy rays to kill cancerous cells. Radiotherapy targets a localized area and kills cancer cells only in that particular area. Radiotherapy may be used to shrink the tumor during the preoperative period or to damage cancer cells that remain in the surgical operation area during the postoperative period. Physicians also frequently resort to radiotherapy as first line treatment in combination with chemotherapy in lieu of surgery. Radiation therapy may also be used to eliminate symptoms such as shortness of breath.

Photodynamic treatment is a kind of laser therapy involving the injection of a special chemical agent into the blood and its absorption by the cell in the body. Although the chemical agent is rapidly segregated from normal cells, it stays in cancerous cells for a long time. A laser beam targeting the cancer activates the agent and kills any cancer cells that have previously absorbed it. Photodynamic therapy may be used to mitigate the symptoms of lung cancer such as keeping hemorrhage under control or the elimination of respiratory problems due to the respiratory tract blocked by an inoperable tumor. Furthermore, photodynamic therapy is also used in the treatment of very small tumors in lung cancer patients who are not eligible for normal treatment methods.

Treatment of Non-Small Cell Lung Cancer: Various treatment options are available for patients with non-small cell lung cancer. The selection of the treatment usually depends on the size, location and dissemination of the tumor. Surgery is the most commonly used method for the treatment of this type of lung tumors. Radiotherapy and chemotherapy are also used to slow the progression of the disease and to treat symptoms.

Treatment of Small Cell Lung Cancer: Small-cell lung cancer spreads rapidly. In many cases, cancerous cells have already spread to other parts of the body by the time the condition is diagnosed. Physicians nearly always resort to chemotherapy to catch cancerous cells throughout the body. Treatment also involves radiotherapy targeting tumors in lung or other parts of the body (such as the brain). Some patients undergo radiotherapy in spite of not having a brain tumor. This treatment is called as protective irradiation of the head and used to prevent the formation of a brain tumor. Surgical operation constitutes part of the treatment plan for a small number of patients with small cell lung cancer.

After Treatment

mportance of Follow-up: Patient follow-up is critical following lung cancer. Regular check-ups allow detection of changes in the health status, and a treatment offer as soon as possible in cases when cancer relapses or a new cancer develops. Check-ups may involve physical examination, lung radiography or laboratory tests. During the predetermined period of time, lung cancer patients must inform their physicians about any health issues as soon as possible.

Provision of Emotional Support: Living with a serious disease such as cancer means to challenge life. Apart from having to deal with physical and medical complications, cancer patients also face many worries and feelings making their lives difficult. These patients need help to overcome not only the actual aspect but also the emotional aspect of their condition. It is part of the treatment plan to take real care of the emotional and psychological aspects of cancer. The health team (physicians, nurses, social workers and others), support groups and patient-patient relations may ease the solitude and sorrow felt by patients and enhance their quality of life. Cancer support groups offer a suitable environment to allow patients to talk with other cancer patients, who experienced a similar stage in their lives, about life with cancer. Patients may wish to speak to a member of the health team to find out about support groups.

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