Seite - 108 - in Cancer Nanotheranostics - What Have We Learnd So Far?

Alcantaraet al. Molecular imagingofbreast cancer FIGURE1 |Microcalcifications inbreastmammography.Highly suggestiveofmalignancyBIRADS5. homogenize the diagnosis and injury treatmentmethods in all centers. BIRADSCLASSIFICATION Category0: Additional imaging evaluation and/or comparison topriormammograms isneeded. Category1: Negative. Category2: Benign(non-cancerous)finding. Category3: Probablybenignfinding–Follow-upinashort time frameis suggested. Category4: Suspicious abnormality –Biopsy shouldbe consid- ered: Category4A:Findingwitha lowsuspicionofbeing cancer. Category 4B: Finding with an intermediate suspi- cionofbeingcancer. Category4C:Findingofmoderateconcernofbeing cancer,butnotashighasCategory5. Category5: Highly suggestive of malignancy – Appropriate actionshouldbetaken. Category6: Known biopsy-proven malignancy – Appropriate actionshouldbetaken. The main diagnosis and monitoring techniques of breast dis- ease includemammography,ultrasoundandmagnetic resonance imaging(MRI). MAMMOGRAPHY Mammographyis themostcommonlyusedmethodforthemon- itoring and diagnosis of breast disease. In recent years, digital mammography has been developed, which requires lower doses of radiation as compared to a conventionalmammography, and alsoallows thepost-processingof images. Mammographyisalsousedtoguideinterventionalbreasttech- niques, suchas stereotacticmammography.Twomammographic views, cranio-caudal andobliquemediumlateral areusuallyper- formed and complementedwith other projections according to needs. This technique has high sensitivity for the diagnosis of microcalcifications. It is also used for breast screening, allowing thedetectionofbreast lesionsataveryearlystage,whichincreases considerably the life expectancy of affected patients. According to the screeningprogram,amammography isusuallyperformed every two years (two projections) in women over the age of 40 or 50,with double readby twodifferent radiologists (Houssami etal., 2009). However,mammographystillpresentsomedrawbacks.Firstly, it is an ionizing technique, and although the radiation dose has considerably decreased, it is still relevant ifwe take into account that the breast is a radiosensitive tissue. Secondly, mammogra- phy cannot differentiate between liquid lesions, including cysts, and solid lesions, which is a major limitation for the accurate identificationof tumormasses. Two innovative techniques are included within mammography: Contrast-enhancedmammography Contrastmammography, aswell asMRI, allowsdynamic vascu- lar studies to beperformed. Several parameters canbe extracted fromtheenhancementcurvethatprovideusefuldiagnostic infor- mation, such as the slope and the time to peak. Thus, lesions withearlyandintenseenhancementaresuggestiveofmalignancy (Fallenbergetal., 2014). This type of study has been satisfactorily used for the anal- ysis of inconclusive lesions, the detection of occult lesions, the monitoring of disease progression and to assess chemotherapy response(Dromainetal., 2009). Tomosynthesis Tomosynthesis techniques allow us to carry out three- dimensional breast studies. It consists of a mammography device that uses a rotaryhead tube, performingdifferent projec- tions of a static breast with a specified angle (between 15◦ and 45◦). It can be considered a tomographic application of digital mammography.Tomosynthesishas evenbeenproposedasanew screening method (Waldherr et al., 2013). Tomosynthesis has demonstrated superior accuracy compared tomammography in tumormeasurements and reduced the suspicious presentations of normal tissues and tissue overlap, and facilitated accurate differentiation of lesion types (Fornvik et al., 2010; Alakhras etal., 2013). ULTRASOUND Ultrasound complements mammography, being a required method for themanagement and diagnosis of breast pathology (Figure2).Because itdoesnotuse ionizingradiation,ultrasound isnotonly thefirstdiagnostic tool inyoungwomenwhohave lit- tle riskofbreast cancer, but also thefirst diagnostic technique in Frontiers inChemistry | ChemicalEngineering December2014 |Volume2 |Article112 | 108