The value of ¹⁸F-FDG PET/CT in diagnosing brain metastases from unknown primary tumor

Objective To investigate the value of ¹⁸F-FDG PET/CT in diagnosis of brain metastases from unknown primary tumor.

Method The ¹⁸F-FDG PET/CT findings of 17 patients with brain metastases from unknown primary tumor were retrospectively analyzed.

Results Primary tumors of the seventeen cases were confirmed by biopsy, the accuracy rate was 100%. There were thirteen cases with primary lung cancer, accounted for 76%, including two cases of lung cancer which were found in the second PET/CT examination, two cases with liver cancer, accounted for 12%, one case with cardia cancer, accounted for 6%, one case with the ascending colon cancer, accounted for 6%. On the base of founding the primary tumor, ¹⁸F-FDG PET/CT also found 10 cases accompanied by lung metastasis(2 cases), lymph node metastases(3 cases), bone metastases(2 cases)and other sites of metastases(3 cases), a total of 61 lesions were detected. Two cases of liver cancer patients with single brain metastases had cerebral apoplexy.

Conclusion ¹⁸F-FDG PET/CT contributes important value in finding brain metastases from unknown primary tumor, and is very helpful for clinical staging and treatment.