1% of asymptomatic "health" individuals found to have cancer (early) on PET scans

[Lani]

considering the radiation exposure( not to say the cost) of the test, it is unlikely to prove a useful screening test.

24 August 2007

Whole-body FDG-PET scans reveal cancer in 1% of healthy individuals

MedWire News: Just under 1% of asymptomatic healthy individuals are diagnosed with cancer using whole-body 18F-fluorodeoxyglucose positron emission tomography (FDG-PET), Japanese investigators have discovered.

The researchers say that further studies are needed to assess the usefulness of such scanning.

FDG-PET is used worldwide for the detection, differential diagnosis, staging, and treatment evaluation of cancer, including breast cancer, lung cancer, colon cancer, esophageal cancer, head and neck cancer, malignant lymphoma, and melanoma.

For the current study, Shinsuke Kojima, from Kyoto University Hospital, and colleagues examined the diagnostic performance of cancer screening using whole-body FDG-PET, studying 5807 asymptomatic healthy volunteers who were scanned between 2002 and 2003. For each participant, whole-body FDG-PET was combined with other diagnostic tests.

Data for complete analysis were available for 4881 participants. Of these, 562 had abnormal FDG uptake on PET screening, and 324 had possible or probable malignancy. However, just 36 participants received a histological diagnosis of cancer.

These consisted of 16 cases of thyroid cancer, seven of colon cancer, four lung cancer cases, five of breast cancer, two of prostate cancer, and one each of renal cell carcinoma, and simultaneous ovarian and endometrial cancer. Of these confirmed cancer cases, three of colon cancer, two of lung cancer, one of breast cancer, and one of renal cell carcinoma were found to be at TNM stage I.

Overall, the cancer detection rate with FDG-PET whole-body screening was 0.7%, at a sensitivity of 70.6% and a specificity of 94.0%, the results, published in the European Journal of Cancer, indicate.

“In PET cancer screening... cancers were detected by PET scans in 0.7% of all subjects, a value that is comparable to the rates found in other studies,” the team writes. “This result suggests that additional prospective studies on PET cancer screening should be conducted in the future.”



Eur J Cancer 2007; 43: 1842–1848

http://www.ejcancer.info/article/PII...04029/abstract