{Reference Type}: Journal Article
{Title}: Prognostic value of the 21-Gene Breast Recurrence Score® assay for hormone receptor-positive/human epidermal growth factor 2-negative advanced breast cancer: subanalysis from Japan Breast Cancer Research Group-M07 (FUTURE trial).
{Author}: Iwamoto T;Niikura N;Watanabe K;Takeshita T;Kikawa Y;Kobayashi K;Iwakuma N;Okamura T;Kobayashi T;Katagiri Y;Kitada M;Tomioka N;Miyoshi Y;Shigematsu H;Miyashita M;Ishiguro H;Masuda N;Saji S;
{Journal}: Breast Cancer Res Treat
{Volume}: 0
{Issue}: 0
{Year}: 2024 Jun 26
{Factor}: 4.624
{DOI}: 10.1007/s10549-024-07414-7
{Abstract}: OBJECTIVE: This study aimed to determine whether the 21-Gene Breast Recurrence Score® assay from primary breast tissue predicts the prognosis of patients with hormone receptor-positive and human epidermal growth factor 2-negative advanced breast cancers (ABCs) treated with fulvestrant monotherapy (Group A) and the addition of palbociclib combined with fulvestrant (Group B), which included those who had progression in Group A from the Japan Breast Cancer Research Group-M07 (FUTURE trial).
METHODS: Progression-free survival (PFS) and overall survival (OS) were compared using the log-rank test and Cox regression analysis based on original recurrence score (RS) categories (Low: 0-17, Intermediate: 18-30, High: 31-100) by treatment groups (A and B) and types of ABCs (recurrence and de novo stage IV).
RESULTS: In total, 102 patients [Low: n = 44 (43.1%), Intermediate: n = 38 (37.5%), High: n = 20 (19.6%)] in Group A, and 45 in Group B, who had progression in Group A were analyzed. The median follow-up time was 23.8 months for Group A and 8.9 months for Group B. Multivariate analysis in Group A showed that low-risk [hazard ratio (HR) 0.15, 95% confidence interval (CI) 0.04-0.53, P = 0.003] and intermediate-risk (HR 0.22, 95% CI 0.06-0.78) with de novo stage IV breast cancer were significantly associated with better prognosis compared to high-risk. However, no significant difference was observed among patients with recurrence. No prognostic significance was observed in Group B.
CONCLUSIONS: We found a distinct prognostic value of the 21-Gene Breast Recurrence Score® assay by the types of ABCs and a poor prognostic value of the high RS for patients with de novo stage IV BC treated with fulvestrant monotherapy. Further validations of these findings are required.