NUCLEAR MEDICINE AND ONCOLOGY 

The Quarterly Journal of Nuclear Medicine and Molecular Imaging 2004 June;48(2):109-18

Copyright © 2009 EDIZIONI MINERVA MEDICA

lingua: Inglese

Position of nuclear medicine modalities in the diagnostic work-up of breast cancer

Buscombe J. R. ¹, Holloway B. ¹, Roche N. ¹, Bombardieri E. ²

¹ Royal Free Hospital, London, UK 2 Istituto Nazionale per lo Studio e la Cura dei Tumori, Milano, Italy

Breast ­tumors can be ­imaged by dif­fer­ent modal­ities: mam­mog­ra­phy is the ­most wide­ly ­used tech­nique ­because of its diag­nos­tic val­ue, ­patient com­pli­ance and low ­costs. Some tech­niques ­such as ultra­sound (US) are ­often indi­cat­ed, ­while oth­ers, ­such as dig­i­tal mam­mog­ra­phy and mag­net­ic res­o­nance imag­ing (MRI) are ­still ­under eval­u­a­tion and ­seem to be ­very prom­is­ing. Among the nucle­ar med­i­cine tech­niques ­breast scin­tig­ra­phy ­with 99mTc-­labelled lip­o­phil­ic cat­ions (SestaMIBI or tet­ro­fos­min), posi­tron emis­sion tomog­ra­phy (PET) ­with 18F-2-­deoxy-2-flu­o­ro-D-glu­cose (FDG) ­have ­been eval­u­at­ed in ­many clin­i­cal ­trials. At ­present ­breast scin­tig­ra­phy has lim­it­ed appli­ca­tions due to its ­poor spa­tial res­o­lu­tion, ­which has a min­i­mum of 8 mm. It is ques­tion­able wheth­er sin­gle pho­ton emis­sion tomog­ra­phy (SPECT) can ­offer any sub­stan­tial­ly bet­ter infor­ma­tion on the ­breast; how­ev­er, ­SPECT is ­more accu­rate in detect­ing axil­lary ­lymph ­nodes. Recent approach­es ­using ­breast ded­i­cat­ed col­li­ma­tors and cam­e­ras ­have great­ly ­improved the ­SPECT res­o­lu­tion and sen­si­tiv­ity. The ­most inter­est­ing tech­nique ­offered by nucle­ar med­i­cine ­today are PET and lym­phos­cin­tig­ra­phy ­with the intra­op­er­a­tive detec­tion of han­dled γ ­probe. The sen­ti­nel ­node detec­tion has ­achieved a ­large con­sen­sus of reli­abil­ity and at ­present it has an impor­tant ­place in the clin­i­cal man­age­ment. In the ­same ­time ­many ­authors ­have acknowl­edged the val­ue of PET in the dif­fe­ren­tial diag­no­sis of ­breast ­lesions and in loco­re­gion­al stag­ing, ­since ­breast can­cer is strong­ly ­avid for glu­cose. PET dem­on­strat­ed ­also its effi­ca­cy in detect­ing axil­lary ­lymph ­node metas­ta­ses. Even in ­some clin­i­cal ­trials its accu­ra­cy ­proved near­ly com­par­able to ­that of lym­phos­cin­tig­ra­phy ­with sen­ti­nel ­node biop­sy, oth­er stud­ies ­showed ­that PET scan­ning ­does not cur­rent­ly ­have ade­quate spa­tial res­o­lu­tion to ­detect ­both ­micro- and ­small mac­ro­met­a­stat­ic dis­ease in axil­lary ­lymph ­nodes. The add­ed val­ue of PET in ­breast can­cer stag­ing is ­that ­with a sin­gle exam­ina­tion PET ­allows the char­ac­ter­isa­tion of ­breast ­lesions, in addi­tion to com­plete view­ing of the ­entire ­body. Whole-­body PET may sub­sti­tute oth­er diag­nos­tic assess­ments by exam­in­ing the var­i­ous ­regions of poten­tial ­tumour ­spread. The cur­rent diag­nos­tic ­work-up for pre- and ­postoper­a­tive stag­ing ­includes var­i­ous exam­ina­tions: ­chest X-­rays, US of the abdo­men, mam­mog­ra­phy of the con­tra­lat­er­al ­breast. Bone scin­tig­ra­phy ­with 99mTc-diphos­pho­nates and labor­a­to­ry ­tests can ­also be con­sid­ered in wom­en ­with ­large ­tumors or in symp­to­mat­ic ­patients. Computed tomog­ra­phy (CT) and MRI may be ­used in ­order to ­resolve par­tic­u­lar diag­nos­tic prob­lems. The cur­rent appli­ca­tion of ­some of ­these modal­ities ­depends on the ­risk of the sin­gle ­patient of devel­op­ing met­a­stat­ic ­spread, ­which is ­revealed by a num­ber of prog­nos­tic param­e­ters of ­tumor aggres­sive­ness and of ­course, clin­i­cal ­stage. Bone scin­tig­ra­phy and PET may be use­ful in mon­i­tor­ing ther­a­py ­response and in detect­ing ­tumour relaps­es dur­ing fol­low-up. In par­tic­u­lar PET guid­ed by ­tumor mark­ers meas­ure­ments ­shows to ­detect ­more ­lesions ­than oth­er non nucle­ar med­i­cine modal­ities.