Differential expression of prognostic biomarkers between interval and screen-detected breast cancers: does age or family history matter?

• Published in: Breast cancer research and treatment Vol. 129; no. 1; pp. 211 - 219
• Main Authors: Lowery, Jan T., Byers, Tim, Kittelson, John, Hokanson, John E., Mouchawar, Judy, Lewin, John, Merrick, Dan, Hines, Lisa, Singh, Meenakshi
• Format: Journal Article
• Language: English
• Published: Boston Springer US 01.08.2011; Springer; Springer Nature B.V
• Subjects: Adult; Age; Age Factors; Aged; Aged, 80 and over; Antineoplastic agents; Biological and medical sciences; Biomarkers; Biomarkers, Tumor - metabolism; Breast cancer; Breast Neoplasms - diagnosis; Breast Neoplasms - metabolism; Breast Neoplasms - pathology; Cancer research; Cancer therapies; Diagnostic tests; Epidemiology; Family medical history; Female; Gynecology. Andrology. Obstetrics; Host-tumor relations. Immunology. Biological markers; Humans; Mammary gland diseases; Medical sciences; Medicine; Medicine & Public Health; Middle Aged; Oncology; Pharmacology. Drug treatments; Prognosis; Risk factors; Tumors; Biomarkers; Interval breast cancer; Tissue micro-arrays; Breast disease; Prognosis; Etiopathogenesis; Biological marker; Breast cancer; Malignant tumor; Medical screening; Gene expression; Mammary gland diseases; Family story; Treatment; Tissue microarrays; Age; Antecedent; Cancer; Interval
• ISSN: 0167-6806; 1573-7217
• DOI: 10.1007/s10549-011-1448-8

The aim of this study was to compare tumor expression of prognostic biomarkers between interval breast cancers and screen-detected breast cancers overall, and according to age at diagnosis and familial risk. Tissue micro-arrays were constructed from 98 breast cancers (47 interval and 51 screen-detected) diagnosed in women in the Cancer Genetics Network. Arrays were immuno-stained to compare protein expression of six biomarkers including estrogen and progesterone receptor (ER/PR), Her2/neu, EGFR, cytokeratin 5/6, and Ki67. Fisher’s Exact test was used to compare expression between interval and screen-detected cancers. Interval cancers were larger ( P  = 0.04), higher stage ( P  < 0.001), and more likely to have lobular histology ( P  = 0.01) than screen-detected cancers. Overall, interval cancers more often overexpressed EGFR ( P  = 0.01) and were somewhat more likely to be ER− (55% vs. 43%, P  = 0.3), and triple negative (ER−/PR−/Her2−) (21 vs. 12%, P  = 0.26). A greater difference in the proportion of interval versus screen-detected tumors that were ER− (53 vs. 35%; P  = 0.29), PR− (35 vs. 21%; P  = 0.25) and EGFR+ (17 vs. 0%; P  = 0.02) was evident among women over 50. There was a trend toward differential expression among women with familial risk for PR− ( P  = 0.005) and triple negative status ( P  = 0.02). This study provides new data indicating that EGFR may be important in the etiology of interval cancer and be a possible therapeutic target. Our data also suggest that biological differences between interval and screen-detected cancers are more defined in older women. Future studies to confirm this finding and to elucidate novel markers for characterizing interval cancers may be more beneficial to this subgroup.