PET Scan Lung Cancer: May Eliminate Surgery

Research by the Dutch scientist, Harm van Tinteren, MD, has shown that 20% of patients could avoid unnecessary surgery with the use of PET scans lung cancer.

During the study, to test the accuracy of PET scans in discovering the extent of lung cancer tumors, Dr. Tinteren tested 188 patients in all. 92 of them had a series of the usual tests to diagnose lung cancer and 96 patients had the same set of conventional tests followed up with a PET scan.

The results were very compelling in favor of the accuracy of the PET scans and their ability to prevent unnecessary surgery. Of the patients in the standard treatment group, 78 of the 92 had surgery, of which approximately half turned out to be unnecessary or futile. In the group that had the PET scans, 60 of the 96 had surgery of which only a third were considered to be unnecessary or futile.

So, what is a PET scan?
PET stands for Positron Emission Tomography, which doesn't really explain it any better. PET refers to a scanning technology that uses small amounts of glucose containing a radioactive substance. This technique is able to more accurately define the anatomy of the lungs and any abnormalities or tumors that exist.

This glucose mixture is either injected into the patient or inhaled by them, and it then accumulates in the lungs. The radioactive atoms start to break down, releasing smaller particles which are called Positrons (the 'P' of PET). The scanner picks up these radio-labeled compounds and the information is sent to a computer which generates a three dimensional cross section of the lungs. The technique allows doctors to accurately diagnose the size and position of tumors. As the positrons move around the body, any additional tumors are able to be detected.

The traditional method of diagnosis of lung cancer uses chest x-rays and MRI, which are less effective in accurately determining the extent and spread of lung cancers. The standard procedure for early stage lung cancer, that hasn't spread to other organs and tissues, is to surgically remove the tumor from the lungs. Usually one third to a half of the lung is removed during this surgery, and sometime even the whole lung.

Lung cancer patients who have surgery are faced with a hospital stay of between one and two weeks, followed by a recovery period of between one and two months. If the surgery was successful, this time-frame is not a problem. However, if the surgery was unnecessary or futile, the time would have been better spent with family and friends.

So, why would surgery for lung cancer be unnecessary or futile?
With the traditional diagnostic tools of x-ray and MRI, doctors have been unable to clearly assess the stage of the lung cancer. If it is considered that the cancer is in its early stages and has not spread outside the lung, surgery is the best option for successful removal of the tumor. Unfortunately, what often happens is that, during surgery, it is discovered that the cancer had spread more than was estimated, and therefore cannot be removed by the surgery. In these cases, the surgery was futile.

It also happens that, during surgery, the mass seen in the standard tests is actually benign or non-cancerous. A benign tumor doesn't need to be removed because it is harmless, or at the very least, could have been treated with medication, so this surgery was unnecessary. These reasons are behind the research into PET scans lung cancer.