Although tumors of the lung may be benign or malignant, benign tumors are rare. Lung cancer is a malignant abnormal growth or change in the epithelium of the lung. It may be primary or secondary with metastasis from other parts of the body by way of the bloodstream or lymphatic system. Primary bronchogenic carcinoma is mainly a result of chronic exposure to environmental and occupational carcinogens with cigarette smoke being of primary importance in more than half of all cases.
Causes of lung cancer can include exposure to certain carcinogens at work such as asbestos, radiation, chloromethyl ether, other carbon-containing products originating from coal or petroleum, arsenic, nickel and iron oxide. Rarely is cancer of the lung inherited in the genetic sense, but transmission of genetic material provides the framework for potential reaction in individuals. Chromosomes in mitotic cell division may be altered by specific carcinogenic agents, causing permanent chromosomal changes.
Lung cancer symptoms are dependent on many variables such as cell type, biologic behavior of the tumor, location of origin within the lung, and relationship between the tumor and the immunologic defense mechanism of the host, Interaction of these factors largely determine the health of the patient during the clinical course of the disease. Usually patient seeks medical attention because of worsening respiratory symptoms felt and it seems like medications given or bought over the counter could not even alleviate them.
Chronic cough, enlarged lymph nodes, dyspnea, chest pain, hemoptysis, or a change in the character of the sputum are what is commonly experienced. It is not just a temporary cough just like when hit with pepper spray guns. This time, it is even more sever and chronic. The change in symptoms is often slow and subtle and you may not be able to perceive it until late in the course of the cancer. Earlier detection is always a best action to prevent complications.
If the tumor invades adjacent structures in the mediastinum or chest wall, you may seek medical attention for hoarseness, difficulty in swallowing, pleuritic pain like being hit hard with a stun baton on the chest or dyspnea. Occlusion of a larger bronchus may cause post-obstructive atelectasis and pneumonitis with symptoms of pneumonia. Horner’s syndrome may result if the tumor invades the cervical sympathetic nerves. Symptoms include loss of sweating, drooping of the eyelids, abnormal papillary constriction, and recession of eyeball into the orbit.
Initially the most common diagnostic aid is the chest x-ray. The changes are variable and depend on whether the tumor is localized or has spread to adjacent structures. The most important sign is evidence of a change from a previous x-ray result. Cytologic studies are performed on the sputum the patient has coughed to detect malignant cells. Bronchoscopy is indicated in any patient with a chronic cough, wheezing, hemoptysis or a suggested chest x-ray of lung cancer.
Treatment of this type of cancer is determined by cardiac and pulmonary status, immunologic status, histologic type of tumor, and the location and extent of the tumor. Once the tumor has been evaluated and staged, routine treatment modalities are usually instituted.