Sentinel Node (SN) Mapping in High Grade Ductal Carcinoma In-Situ (HG-DCIS)
A Anga, A Moore, B Chamberlain, P McGrath, H Wright, L Samayoa. University of Kentucky, Lexington
Background: The decision to performed SN mapping in HG-DCIS patients undergoing breast conservation remains controversial. Currently many breast cancer centers have adopted this practice based on archival data showing up to 20% incidence of axillary metastasis. This retrospective study correlates key pre-operatory mammographic findings with the incidence of invasive carcinoma (inv-ca) and metastatic disease on final surgical specimens and provides criteria for planning SN mappings in patients with this disease.
Design: Imaging data from 130 patients presenting with mammographically suspicious microcalcifications (Ca++) and Needle Core Biopsy (NCB) proven HG-DCIS, was reviewed for the following: morphology of Ca++ (linear, segmental, clustered, pleomorphic, amorphous, casting); extent of Ca++ (mm); associated parenchymal changes (masses, densities, asymmetries) and correlated with their final diagnosis and axillary status. All patients undergoing simple mastectomies had SN. Patients undergoing lumpectomies had SN only if Ca++ were associated with parenchymal abnormalities and/or at surgeon discretion.
Results: The incidence of inv-ca in patients with mammographic findings of suspicious Ca++ alone (n=91) and extending up to 5 cm. was none; microinvasive (m-inv) disease was present in 5 SN (-) patients. Parenchymal changes with Ca++ were noted in 39 patients: ill defined masses (n=23), increased densities (n = 9) and parenchymal asymmetries (n=7) all associated with Ca++ extending up to 2 cm. In this group, 9 patients had inv-ca and 6 had m-inv disease. Of the ones with inv-ca, 8 had associated ill defined masses, and one had increased parenchymal density pattern; 5 were SN (-), 3 were single (+) SN and one had 4 (+) nodes. Of the ones with m-inv disease, 4 were associated with ill defined masses and 2 with increased parenchymal densities; 5 patients were SN (-) and 1 had a single (+) node. No particular Ca++ morphology or pattern correlated best with the incidence of microinvasive disease or inv. ca. No correlation between extent of Ca++ (up to 5 cm) and incidence of inv-ca was identified.
Conclusions: The management of the axilla in HG-DCIS patients undergoing breast conservation should be planned emphasizing on the patients mammographic findings: For patients with Ca++ alone, SN biopsy is not indicated. On contraire, SN mapping is indicated in patients with suspicious Ca++ associated with parenchymal changes, particularly if the changes are ill defined masses, even if the NCB shows no evidence of inv-ca.
Wednesday, March 24, 2010 9:30 AM
Poster Session V # 44, Wednesday Morning