If this is not your name, click here.
| | If this is not your name, click here. | | |
| | Contact Us | Order Now | Journals | Bookstore | Register a colleague | | |
| |  PET-CT Helps Detect Underlying Cancers in Patients With Neurologic Symptoms CHICAGO -- January 11, 2010 -- A combined positron emission tomography (PET)-computed tomography (CT) scan of the whole body appears to detect cancer in individuals with related neurologic complications more accurately than some other commonly used tests, according to a study published early online and appearing in the March issue of the Archives of Neurology. “In the assessment of patients with suspected paraneoplastic neurologic disorders, routine non-invasive oncologic evaluations may be unrevealing,” the authors wrote as background information in the article. “These standard evaluations include physical examination; CT of the chest, abdomen, and pelvis; mammography in women; and testicular ultrasonography and prostate-specific antigen testing in men.” Cancers underlying paraneoplastic neurologic disorders are typically small, restricted to one site and are often not detected until autopsy. Andrew McKeon, Mayo Clinic, Rochester, Minnesota, and colleagues analysed the medical records of 56 consecutive patients with suspected paraneoplastic neurologic disorders whose standard evaluations (including CT) did not reveal cancer. All of them underwent PET-CT at Mayo Clinic between 2005 and 2008. PET-CT detected abnormalities suggestive of cancer in 22 of the patients (39%), of whom 10 (18%) had cancer diagnoses confirmed by biopsy or another method. Of these cancers, 2 were in the thyroid, 1 was in the tonsil, 3 were in the lungs, 1 was in the colon, and 3 were cancerous lymph nodes with unknown primary cancer sites. Of the 10 cancers, 9 were early-stage cancers and detection facilitated early treatment. Cancer remission was reported in 7 patients and improvement in neurologic symptoms in 5 patients after a median (of 11 months of follow-up. Before their PET-CT, patients underwent a median of 3 other screening tests; the most common was CT of the chest, abdomen, and pelvis. “However, 4 of the 10 detected cancers using PET-CT were outside the anatomical scope of CT of the chest, abdomen, and pelvis (thyroid, 2; cervical lymph node, 1; and palatine tonsil, 1),” the authors wrote. “The other 6 detected cancers were too small to be detected by appropriate regional CT (lung, 4; axillary lymph node, 1; and colon, 1). Clearly, CT alone is not sufficient to exclude cancer in cases with a high index of suspicion for cancer.” Some types of cancer, including bladder and kidney cancers, are more difficult to detect by PET-CT, the authors noted. “Recognising the limitations of PET-CT, we favour this modality for initial oncologic evaluation of patients in whom a paraneoplastic neurologic disorder is strongly suspected,” they concluded. “Elimination of whole-body imaging with CT alone before further imaging with PET-CT could reduce radiation exposure and the total financial burden of testing.”
SOURCE: Archives of Neurology
|
