Detecting cancer can you trust all the tests – australian national review bleeding after endometrial biopsy

“Many different conditions can cause an increase in CA 125, including normal conditions, such as menstruation, and noncancerous conditions, such as uterine fibroids. Certain cancers may also cause an increased level of CA 125, including ovarian, endometrial, peritoneal and fallopian tube cancers.”

“Your doctor may recommend a CA 125 test for several reasons: But such monitoring hasn’t been shown to improve the outcome for those with ovarian cancer, and it might lead to additional and unnecessary rounds of chemotherapy or other treatments.”

“…some people with ovarian cancer may not have an increased CA 125 level. And no evidence shows that screening with CA 125 decreases the chance of dying of ovarian cancer. An elevated level of CA 125 could prompt your doctor to put you through unnecessary and possibly harmful tests.”


From acrin.org, About PET Scans: “A PET scan uses a small amount of a radioactive drug, or tracer, to show differences between healthy tissue and diseased tissue. The most commonly used tracer is called FDG (fluorodeoxyglucose), so the test is sometimes called an FDG-PET scan. Before the PET scan, a small amount of FDG is injected into the patient…”

Introduction to PET/CT Imaging: “Cancer cells are not always the only ‘PET avid cells’ (or cells that take up the FDG) in the body. It is important to remember that a PET scan is not able to distinguish metabolic activity due to tumor from activity due to non cancerous processes, such as inflammation or infection.”

PET scan findings can be false positive: “In cancer cells, there is an overproduction of glucose transporters and, as a result, increased FDG uptake. However, not all PET-positive lesions are cancer, and in many instances, PET findings can be false positive. … Inflammatory cells also have increased metabolic rates and, as a result, are FDG avid.”

“Many of us have had patients or know of patients who were treated by the medical oncologist for stage IV cancer only to find out what was assumed to be a metastatic lesion was benign on pathology. Other patients have undergone multiple biopsies of supposed metastatic mesenteric lymph nodes that subsequently turned out to be fat necrosis or a granulomatous reaction. FDG-positive lesions often mean cancer, but not always. A variety of lesions have increased FDG radiotracer [the “lighting up” phenomenon]including infection, inflammation, autoimmune processes, sarcoidosis, and benign tumors. If such conditions are not identified accurately and in a timely manner, misdiagnosis can lead to inadequate therapies.”

Causes and imaging features of false positives and false negatives on 18F-PET/CT in oncologic imaging: Causes and imaging features of false positives and false negatives on 18F-PET/CT in oncologic imaging “Glucose however acts as a basic energy substrate for many tissues, and so 18F-FDG activity can be seen both physiologically and in benign conditions. In addition, not all tumors take up FDG [3–5]. The challenge for the interpreting physician is to recognize these entities and avoid the many pitfalls associated with 18F-FDG PET-CT imaging.”

The question is, after a patient is told he has received a positive PET scan, indicating cancer, will the physician spell out all the factors that could have made the test read FALSELY POSITIVE? Will an intelligent and honest and informed conversation take place, or will the doctor shove the test results at the patient and declare: “You have cancer.”