Diagnostic Performance of F18-FDG PET/CT in Male Breast Cancers Patients.

INTRODUCTION: F18-FDG PET/CT is the most important hybrid imaging used in the diagnostic, staging, follow-up, and treatment evaluation response in cancer patients. However, it is well-known that in breast cancer the use of F18-FDG is not included in the first line protocol of initial diagnostic, both in female and male breast cancer patients. F18-FDG PET/CT is a valuable tool to provide information on extra-axillary lymph node involvement, distant metastases, and other occult primary cancers. This study assesses F18-FDG PET/CT systemic staging in male patients with diagnosed breast cancer and determines detection rates for unsuspected distant metastases and synchronous malignancies.

METHODS: We analyzed a number of 170 male patients with breast cancer, seen between 2000-2020, in a tertiary center. From this group, between 2013-2020 a number of 23 patients underwent F18-FDG PET/CT. Rates of upstaging were determined for each case and the detection of other primary malignancies was analyzed.

RESULTS: Median age of male breast cancer group was 61.3 y (range, 34-85 y), most had intraductal carcinoma (82.4%) and unsuspected distant metastases, which increased patient stage to IV, observed in 27%. In 4 out 23 patients (17.4%), F18-FDG PET/CT identified synchronous cancers (2 prostate cancers, 1 thyroid and 1 colon cancer).

CONCLUSION: F18-FDG PET/CT is a valuable tool to provide information on extra-axillary lymph node involvement, distant metastases, and other occult primary cancers. Baseline F18-FDG PET/CT has a substantial impact on the initial staging and on clinical management in male breast patients and should be considered for use in newly diagnosed patients.