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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: OBJECTIVE, METHODS, RESULTS. Meshes: Adult, Aged, CA-19-9 Antigen, Female, Fluorodeoxyglucose F18, Humans, Male, Middle Aged, Neoplasms, Positron-Emission Tomography, Predictive Value of Tests, Radiopharmaceuticals, Retrospective Studies.
user
Is increase of serum CA19-9 level without an evident lesion on conventional imaging insufficient for justification of 18FDG-PET examination? Context: The serum tumor marker carbohydrate associated antigen 19-9 (CA19-9) has been used for screening for cancer, because its increase has been associated with many cancers. We aimed to evaluate the clinical value of positron emission tomography using F-18 fluorodeoxyglucose (18FDG-PET) that was prompted by increases of serum CA19-9 without findings on conventional imaging. Twenty-two patients were retrospectively selected. Eleven were without a history of cancer and eleven had a history of cancer and were treated with curative intent. All 18FDG-PET findings were compared with the findings of histopathology by surgery or biopsy, or clinical follow-up for at least 1 year. We found only two true positive cases, and eleven cases without a cancer history included 10 true negatives and one false positive.
assistant
Increases in serum CA19-9 are caused by many benign conditions. Increases of CA19-9 without findings on conventional imaging do not justify 18FDG-PET examination, particularly in patients without a cancer history. Final Decision: yes