The Value of Ki67 in Very Young Women with Hormone Receptor-Positive Breast Cancer: Retrospective Analysis of 9,321 Korean Women.

Abstract

BACKGROUND:

Young breast cancer patients have a poorer prognosis, especially when their tumors are hormone receptor positive. We analyzed the association between Ki67 and age and the impact of these factors on outcomes in hormone receptor-positive breast cancer.

METHODS:

The records of 9,321 hormone receptor-positive invasive breast cancer patients from three large centers were retrospectively reviewed. Each institution separately assayed Ki67 level immunohistochemically. Univariate and multivariate analysis for recurrence-free survival (RFS) was performed on 4,738 patients from a single center.

RESULTS:

Ki67 level was inversely proportional to age in all three data sets and was significantly higher for younger patients (p < 0.001, 0.03, and <0.001, respectively). This correlation was seen only in the human epidermal growth factor receptor 2 (HER2)-negative population. Survival analysis showed that both very young age (<35 years) and high Ki67 level (≥10 %) were independent prognostic factors. Although young age was a worse prognostic indicator regardless of HER2 status, Ki67 index was associated with worse prognosis only in HER2-negative patients. When patients were stratified into those with low and high Ki67, young age remained a significant factor for RFS, with hazard ratios in these two Ki67 groups of 2.15 and 2.57, respectively (p < 0.001). Also, the young age/low Ki67 group had significantly poorer RFS than the older age/high Ki67 group (p < 0.001).

CONCLUSIONS:

Ki67 level was higher in younger patients. However, very young patients had a poorer prognosis regardless of Ki67 level. Unknown biologic factors other than high cell proliferation might play a role in the aggressiveness of hormone receptor-positive breast cancer in very young patients.

• Authors: Jisun Kim, Wonshik Han, So-Youn Jung, Yeon Hee Park, Hyeong-Gon Moon, Soo Kyung Ahn, Jun Woo Lee, Min Kyoon Kim, Jong Jin Kim, Eun Shin Lee, Tae Kyung You, Han-Sung Kang, Eun Sook Lee, Jungsil Ro, Jeong Eon Lee, Seok Jin Nam, Young-Hyuck Yim, In Ae Park, Dong-Young Noh
• Journal: Annals of surgical oncology (Ann Surg Oncol) Vol. 22 Issue 11 Pg. 3481-8 (Oct 2015) ISSN: 1534-4681 [Electronic] United States
• PMID: 25652052 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Ki-67 Antigen
• Receptors, Estrogen
• Receptors, Progesterone
• ERBB2 protein, human
• Receptor, ErbB-2

Topics

• Adult
• Age Factors
• Aged
• Aged, 80 and over
• Breast Neoplasms (chemistry, pathology, therapy)
• Disease-Free Survival
• Female
• Humans
• Ki-67 Antigen (analysis)
• Lymphatic Metastasis
• Middle Aged
• Receptor, ErbB-2 (analysis)
• Receptors, Estrogen (analysis)
• Receptors, Progesterone (analysis)
• Republic of Korea
• Retrospective Studies
• Risk Factors
• Young Adult