Diagnosing lung cancer

Lung cancer is one of the highest prevailing diseases in our world today. Like any other cancer, it occurs due to the abnormal growth of cancerous cells originating either from the lung tissue itself or elsewhere in the body and metastasizing to the lung. Most of the cases are diagnosed at a later stage where the cancer has spread and increased in severity. However, proper diagnosis and treatment can go a long way.

A thorough medical history of the patient is always the first step towards establishing a diagnosis. It points the physician towards the right direction; a correct diagnosis.

Various tests are performed in patients in order to diagnose lung cancer. The information from these tests enables the physician to determine the type and stage of the cancer and the best way to treat it. The tests include physical examination, chest examination, chest X-ray, CT scan, positron emission tomography (PET) scan, MRI, sputum cytology, bronchoscopy, biopsy and spiral CT scan.

Physical examination is important for detecting any external signs of cancer such as swollen lymph nodes in the neck or nearby area that can point towards a possible diagnosis.

Examining the chest and listening to the lungs with a stethoscope provides information about abnormal breathing sounds or patterns that may be characteristic to the disease.

Computed tomography, also known as CT or CAT scan, is a sophisticated instrument that uses a computer to create a two-dimensional scan from a series of X-ray images. The newest version of the CT is called a helical or spiral scan. CT scans show much more detail than x-rays and the new helical or spiral scans are even more sensitive than regular CT scans. Extensive details of cancer affected tissues, if present, can be received through this scan. MRI is similar to a CT scan except is uses a magnetic field instead of X-rays to create an image. The spiral (or helical) CT scan can image the lungs in a single breath hold and are more sensitive than the normal CT scans.

Chest X-rays are "flat" pictures of the lungs, which help in identifying any abnormal growths. The variation in the resulting picture depends on the variable density of the tissues that the radiation is passing through.

Recently published results from a large clinical trial showed that annual screening with chest x-ray does not reduce mortality. Newer tests, such as low-dose spiral CT scans and molecular markers in sputum, have produced promising results in detecting lung cancers at earlier, more operable stages in high-risk patients. Results from the National Lung Screening Trial, showed 20% fewer lung cancer deaths among current and former heavy smokers who were screened with spiral CT compared to standard chest x-ray.

Positron Emission Tomography (PET) is a scan that makes a diagnosis using a cancer's rapidly dividing cells. Radiologists administer a radioactive substance to the patient that will be absorbed more by the cancer than by normal tissues, due to the cancer cells' increased need for energy. The PET scan records the areas where the radioactivity is focused.

Sputum cytology examines phlegm coughed out by the patient, under a microscope to check for abnormal or cancerous cells. More information on treatments can be found on healthcarevilla.com.

Bronchoscopy is viewing of the lungs through a lighted, flexible tube (bronchoscope) that is passed through the nose and throat into the main airway of the lungs. The tube, which has a light on the end, allows the doctor to see inside of the lung. If abnormal areas or tumors are seen, cell tissue samples can be obtained through special tools located at the end of the bronchoscope for evaluation under a microscope. These samples are also called biopsy samples. A biopsy sample can be obtained in other different ways, depending on the location of the tumor. For example, by inserting a needle through the chest into the lung and removing part of the tissue for testing, by removal and examination of an enlarged lymph node in the neck or by a small surgery on the lung.