Background: To assess the prognostic capability of the maximum standardized uptake values (SUV max ) measured in the primary tumor and axillary lymph nodes (ALNs) by pretreatment fluorine-18-fluorodeoxyglucose positron emission tomography/computed tomography and analyze outcomes according to the molecular breast cancer subtypes.Methods: The databases were systematically searched using keywords for breast cancer, positron emission tomography/ computed tomography, and SUV max ; the extracted studies reported at least 1 form of survival data, event-free survival (EFS) and overall survival. Comparative analyses of the pooled hazard ratios (HRs) for EFS and overall survival were performed to assess their correlations with SUV max . The pooled HR was estimated using random-effects model according to the results of heterogeneity.Results: Thirteen eligible studies comprising 3040 patients with breast cancer were included. The pooled HRs of high SUV max in the primary tumor and ALN were 3.01 (95% CI 1.83-4.97, P < .00001; I2 = 82%) and 3.72 (95% CI 1.15-12.01; I2 = 92%; P = .03), respectively. Patients with higher SUV max demonstrated a poorer survival prognosis. Furthermore, comparative analyses according to the molecular subtypes demonstrated that the SUV max in the primary tumor or ALN can be a predictive parameter in patients with the luminal subtype disease. Subtype analysis results indicated a significant association of the luminal group, with a HR of 2.65 (95% CI 1.31-5.37; I2 = 27%; P = .007).Conclusions: SUV max from pretreatment is a significant prognostic factor for EFS in patients with breast cancer. Despite several limitations, correlation with molecular subtype (luminal type) was demonstrated. Further large-scale studies are required to investigate the precise prognostic capability of SUV max .Abbreviations: 18 F-FDG PET/CT = fluorine-18-fluorodeoxyglucose positron emission tomography/computed tomography, ALN = axillary lymph node, EFS = event-free survival, ER = estrogen receptor, HER2 = human epidermal growth factor receptor 2, HR = hazard ratios, MFS = metastasis-free survival, OS = overall survival, SUV max = maximum standardized uptake values.

Metastasis to breast from ovarian cancer is very rare, and it is very difficult to distinguish the primary breast cancer from the secondary one. In our case, a 61-year-old woman presented to the hospital with complaints of lower abdominal pain and distention. Abdominal-pelvic computed tomography (CT) imaging revealed a solid ovarian cystic tumor with numerable ascites in the abdominal cavity and disseminated peritoneal carcinomatosis. To confirm the presence of metastasis in other organs, a preoperative imaging studies including chest CT was performed. Chest CT imaging revealed an enlargement of both the axillary lymph nodes (r/o metastatic lymphadenopathy) and breast imaging studies (breast sonography and mammography) revealed masses penetrated the pectoralis major muscle in the left breast and metastatic lymphadenopathy in Lt axilla. The core needle biopsy result of breast lesion showed unknown origin carcinoma with micropapillary features and no psammoma bodies. So, we could not distinguish primary breast cancer and breast metastasis from ovarian cancer because breast metastasis from ovary could be contained psammoma bodies, generally. Although the possibility of primary breast cancer could not be ruled out absolutely, the neoadjuvant chemotherapy included Paclitaxel and Carboplatin is known to be effective for both breast and ovarian cancer. So after neoadjuvant chemotherapy, mastectomy concurrently with ovarian cancer surgery was performed. The histopathologic features of the ovaries and breast were similar and psammoma bodies also could be observed, which were not detected in previous core needle biopsied specimen. And lymph nodes from the breast and the ovaries also showed consistent findings. Combined with histopathologic report and medical records, the final diagnosis confirmed as a metastasis of ovarian cancer to breast. After surgery, the patient has continued with metastatic ovarian cancer specific treatment. Breast metastatic tumors must be distinguished from primary breast tumors to avoid any unnecessary surgery. It might be difficult to diagnosis precisely by using only core needle biopsy because of inadequate specimen volume. Although surgical resection may be effective for both diagnosis and palliative treatment, further studies focused on less invasive biopsy are needed for exact histopathological diagnosis.