The importance of standardized interpretation of molecular breast imaging with dedicated gamma cameras

Abstract

Breast cancer (BC) is the most common malignancy and the second leading cause of cancer death in females, accounting in the USA for 29% of the total new cancer cases and 14% of the total cancer deaths in 2012 [1]. Early diagnosis and treatment are of the utmost importance to improve prognosis.For detection and characterization of primary breast lesions, anatomical imaging including mammography, ultrasonography, and MRI are commonly employed. Scintimammography is a molecular nuclear medicine technique for breast imaging which uses single-photon radiopharmaceuticals such as 99m Tc sestamibi and 99m Tc tetrofosmin. It is a functional imaging modality so some of the main drawbacks of mammography are resolved [2]. It was developed almost 20 years ago with standard large field-of-view (FOV) gamma cameras. Certainly, the principal limiting factor in the clinical acceptance of scintimammography has been its low sensitivity for cancers of ≤1 cm in size, mainly because of the lack of suitable equipment specifically designed for breast imaging.Dedicated gamma cameras specifically built for breast imaging are now available. The use of these breast-optimized, small FOV, high-resolution cameras allows both greater flexibility in patient positioning (improving breast imaging by limiting the FOV and reducing image contamination from other organs, i.e. liver and heart) and breast compression, with an important increase in the target-to-background ratio [3]. In fact, the detector can be placed directly against the chest and a mild compression is possible, to reduce breast thickness and improve the camera's sensitivity. Moreover, by design, these specific cameras are also able to provide better intrinsic and extrinsic spatial resolution than standard ones, with an enhancement in contrast resolution for small lesions [4], and to acquire projections similar to those of mammography (craniocaudal, mediolateral oblique and true lateral).Studies comparing standard and breast-specific cameras have provided clinical evidence that the dedicated ones show better accuracy in molecular breast imaging, especially in increasing the sensitivity for subcentimetre lesions [4][5][6]. It is worth noting that a recent retrospective review of one institution's experience with breast-specific gamma imaging (BSGI) has indicated that this test is not only both sensitive (93%) and specific (79%) for the identification of BC, but it is also helpful as an adjunct to standard breast imaging modalities for problem solving in indeterminate cases [7]. Moreover, in this study including 416 cases, BSGI was demonstrated to be useful in evaluating lesions difficult to biopsy and in patients who desired further testing rather than biopsy or short term follow-up of their breast abnormality. These interesting data have been then confirmed in a multicentre clinical patient registry analysis, which aimed to quantify the impact of BSGI on the management of patients with BC in clinical practice, and to identify the subgroups benefiting more from the use of this examinatio...

Radioactive Molecules 2021–2022

“…The placement of the isotopes in Table 3 , Table 4 , Table 5 , Table 6 and Table 7 depends on how the isotope mainly decays—i.e., whether the main form of its decay is via positron [ 6 , 7 , 8 , 9 ], gamma [ 10 ], beta [ 11 ], Auger [ 12 ], or alpha emissions [ 13 ]. The decay of an isotope will often take place in several ways; however, this review will focus on the main form of decay.…”

Advances in nanocomposites-based electrochemical biosensors for the early diagnosis of breast cancer

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Direct-Conversion Molecular Breast Imaging of Invasive Breast Cancer: Imaging Features, Extent of Invasive Disease, and Comparison Between Invasive Ductal and Lobular Histology

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