A PET scan is a very accurate method for cancer detection. The scan detects areas of active tumor, or foci of hypermetabolism. The results are compared to conventional imaging, which can only detect up to 20% of tumours. PET is not always effective, however, as it can miss some cancers. It is not a cure for cancer, so it should not be relied upon as the only way to detect cancer.
As the field of nuclear medicine has grown, so has the range of PET tests. Just fifteen years ago, the most common type of PET scan was the FDG scan. This was considered to be the gold standard in oncology, and people assumed that the accuracy would be consistent if they mastered only one type. However, it turned out to be more difficult than we thought. Adding PET to other types of imaging data makes the reconstructed images less accurate.
A PET scan can reveal tumors that were previously undetectable, enabling doctors to treat them as early as possible. They can also be used to determine whether or not a particular cancer treatment is working. By revealing the exact location of the cancer, a PET scan can also help determine whether the cancer has spread to other areas of the body. Additionally, a PET scan can catch a potential recurrence earlier than other types of cancer testing.