MammaPrint Feasibility in a Large Tertiary Urban Medical Center: An Initial Experience. (31st December 2012)

• Record Type: Journal Article
• Authors: Espinel, C. Francisco; Keating, Shaughn; Hibshoosh, Hanina; Taback, Bret; Joseph, Kathie-Ann; El-Tamer, Mahmoud; Feldman, Sheldon
• Other Names: Chiarugi Massimo Academic Editor.; Dahiya Sonika Academic Editor.
• Is Part Of: Scientifica. Volume 2012(2012)
• Publication Date: 2012-12-31
• Subjects: Life sciences -- Periodicals; Biology -- Periodicals; Medicine -- Periodicals; Biological Science Disciplines; Medicine; Biology; Life sciences; Medicine; Periodicals; Electronic journals; Periodicals; 500
• DOI: 10.6064/2012/942507
• Languages: English
• ISSNs: 2090-908X

Abstract

Abstract : Background . The MammaPrint (MP) diagnostic assay stratifies breast cancer patients into high- and low-risk groups using mRNA analysis of a 70-gene profile. The assay is validated for assessment of patients with estrogen receptor positive or negative tumors less than 5 cm with 3 or fewer malignant lymph nodes. TargetPrint (TP) is an assay for assessing estrogen, progesterone, and HER2-neu receptor status based on mRNA expression. A potential limitation of these assays is that they require an evaluation of fresh tissue samples. There is limited published experience describing MP or TP implementation. Methods . Over 10 months, 4 breast surgeons obtained samples from 54 patients for MP/TP analysis. The samples were analyzed by Agendia Labs. The tumors were independently evaluated for receptor status using immunohistochemistry (IHC). Retrospectively, we identified patients who were assessed by MP/TP during this period. Patients who underwent OncotypeDx evaluation were also identified. Results . Of the 54 patients receiving MP, 4 were found ineligible for MP risk assessment because >3 lymph nodes were found to be malignant. Out of all eligible patients, 14/50 (28%) had samples whose quantity of tumor was not sufficient for analysis (QNS). Out of eligible patients with tumors <1 cm, 7/8 (88%) had QNS samples. 7/42 with tumors ≥1 cm (17%) had QNS samples. Nine patients had discordant receptor results when evaluated by IHC versus. TP. Of patients who also underwent OncotypeDx testing, 6/14 (43%) had discordant results with MP. Conclusions . This study indicates that using MP/TP assay is feasible in a tertiary care center but there may be utility in limiting MP testing to patients with tumors between 1 and 5 cm due to high likelihood of uninformative results in subcentimeter tumors. Further study is needed to explore the discordance between oncotype and MP results.