I strongly recommend FDGPET/CT to be performed in BC patients prior to surgery for staging, for the assessment of prognosis, and for having baseline images that will be used for comparison with the
follow-up FDG-PET/CT images.
FDG-PET/CTBC patientssurgeryassessment of prognosisFunding information was not reported in the published version of this article.
I wish to make a few important contributions from the point of diagnostic imaging of breast cancer (BC). Surgical treatment decisions for BC including modified radical mastectomy and breast conserving surgery depend on the exact data about the actual extent of BC, particularly on the presence of metastatic locoregional lymph nodes (LNs). Locoregional LNs primarily imply ipsilateral axillary LNs, but also refer to other local LNs including internal mamarian (IM), supraclavicular and infraclavicular LNs ( 1
).
Though mammography, US and magnetic resonance imaging are standard methods in the initial imaging of BC,they were not thought to be the correct tools in precise demonstration of metastatic axillary LNs ( 2
). 18-fluoro deoxyglucose (FDG)-positron emission tomography/computed tomography (PET/CT) was defined as a standard and essential method for initial staging of the BC patients because of its value in demonstration of metastatic locoregional LNs ( 3
). FDG-PET/CT also gives critical information about the prognosis. As compared with other imaging methods, only FDG-PET/CT can maintain two irreplaceable quantitative parameters for the oncologist and the surgeon: Maximum standardized uptake value (SUVmax) of the tumour (SUVmax-T) and SUVmax of the metastatic LNs (SUVmax- LN), which are used to demonstrate the quantity of FDG uptake of the tumoural mass and LNs, respectively. SUVmax-T was found to be significantly higher in patients with recurrent BC ( 4
) and poor prognosis ( 5
). SUV max-T allows to assess prognosis in BC by quantifying the tumour aggressivity.
As another predictor of prognosis, SUVmax- LN prior to therapy can be used as a determinant of disease free survival ( 6
). The presence of metastatic IM LNs is of particular significance in predicting the likelihood of distant metastases and decreased survival rates ( 7
). FDG-PET/CT is also superior to conventional imaging tools in demonstration of metastases in IM LNs ( 8
). However it should also be kept in mind that micrometastases can not be excluded by a negative FDG-PET/CT because of the limitations in the geometric resolution of PET, which was stated to be as low as 5−6 mm ( 9
).
In conclusion, I strongly recommend FDG- PET/CT to be performed in BC patients prior to surgery for staging, for the assessment of prognosis and for having baseline images which will be used for comparison with the follow-up FDG-PET/CT images.
ReferencesEubank WB, Mankoff DA, Vesselle HJ, Eary JF, Schubert EK, Dunnwald LK, et al. Detection of locoregional and distant recurrences in breast cancer patients by using FDG PET. Radiographics 2002; 22: 5−17.Fuster D, Duch J, Paredes P, Velasco M, Muñoz M, Santamaría G, et al. Preoperative staging of large primary breast cancer with [18F]fluorodeoxyglucose positron emission tomography/computed tomography compared with conventional imaging procedures. J Clin Oncol 2008; 26: 4746−51.Koolen BB, Olmos RAV, Elkhuizen PH, Vogel WV, Peeters MJ, Rodenhuis S, et al. Locoregional lymph node involvement on 18F-FDG PET/CT in breast cancer patients scheduled for neoadjuvant chemotherapy. Breast Cancer Res Treat 2012; 135: 231−40.Zhang X, Wu F, Han P. The role of (18)F-FDG PET/CT in the diagnosis of breast cancer and lymph nodes metastases and micrometastases may be limited. Hell J Nucl Med 2014; 17: 177−83.Koolen BB, Peeters MV, Wesseling J, Lips EH, Vogel WV, Aukema TS, et al. Association of primary tumour FDG uptake with clinical, histopathological and molecular characteristics in breast cancer patients scheduled for neoadjuvant chemotherapy. Eur J Nucl Med Mol Imaging 2012; 39: 1830−38.Song BI, Lee SW, Jeong SY, Chae YS, Lee WK, Ahn BC, et al. 18F-FDG uptake by metastatic axillary lymph nodes on pretreatment PET/CT as a prognostic factor for recurrence in patients with invasive ductal breast cancer. J Nucl Med 2012; 53: 1337−44.Yao MS, Kurland BF, Smith AH, Schubert EK, Dunnwald LK, Byrd DR, et al. Internal mammary nodal chain drainage is a prognostic indicator in axillary node-positive breast cancer. Ann Surg Oncol 2007; 14: 2985−93.Choi YJ, Shin YD, Kang YH, Lee MS, Lee MK, Cho BS, et al. The effects of preoperative (18)F-FDG PET/CT in breast cancer patients in comparison to the conventional imaging study. J Breast Cancer 2012; 15: 441−48.Liu Y. Role of FDG PET-CT in evaluation of locoregional nodal disease for initial staging of breast cancer. World J Clin Oncol 2014; 5: 982−89.