Complementary value of the Ki-67 proliferation index to the oncotype DX recurrence score.
Oncotype DX is a 21-gene assay that quantifies the recurrence risk in estrogen receptor-positive breast cancer, which is expressed as the recurrence score (RS). Studies have shown that patients with a high-risk RS will most likely benefit from adjuvant chemotherapy, but there is no proven advantage for patients with a low-risk RS who still face an average recurrence risk of 7%. In this study, the relationship between the RS and the cell cycle-related antigen Ki-67 was assessed in 32 breast carcinomas and evaluated for a potential association. Comparison of the RS with tumor type, grade, and the Ki-67 proliferation index (PI) revealed an overall concordance. However, some tumors with a low RS revealed a surprisingly high Ki-67 PI. These cases may correspond to the 7% of low-risk RS carcinomas that recur. Therefore, the authors propose a combined evaluation of the RS and Ki-67 PI to identify tumors with high recurrence potential from the low-risk and intermediate-risk RS groups.
Gwin
Katja
K
Department of Pathology, Yale University School of Medicine, New Haven, Connecticut, USA. katja.gwin@uchospitals.edu
Pinto
Marguerite
M
Tavassoli
Fattaneh A
FA
D000230:Adenocarcinoma / Q000175:diagnosis* / Q000235:genetics / Q000378:metabolism / Q000556:secondary; D000328:Adult; D014408:Biomarkers, Tumor / Q000378:metabolism; D001943:Breast Neoplasms / Q000175:diagnosis* / Q000235:genetics / Q000378:metabolism; D049109:Cell Proliferation; D005260:Female; D020869:Gene Expression Profiling / Q000379:methods*; D006801:Humans; D007150:Immunohistochemistry; D019394:Ki-67 Antigen / Q000378:metabolism*; D008198:Lymph Nodes / Q000378:metabolism / Q000473:pathology; D008207:Lymphatic Metastasis; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000175:diagnosis* / Q000235:genetics / Q000378:metabolism; D011237:Predictive Value of Tests
D014408:Biomarkers, Tumor; D019394:Ki-67 Antigen