TY - JOUR
T1 - Comparison of Ki-67 labeling index measurements using digital image analysis and scoring by pathologists
AU - Morioka, Toru
AU - Niikura, Naoki
AU - Kumaki, Nobue
AU - Masuda, Shinobu
AU - Iwamoto, Takayuki
AU - Yokoyama, Kozue
AU - Ogiya, Rin
AU - Oshitanai, Risa
AU - Terao, Mayako
AU - Tsuda, Banri
AU - Okamura, Takuho
AU - Saito, Yuki
AU - Suzuki, Yasuhiro
AU - Tokuda, Yutaka
N1 - Funding Information:
Acknowledgements This work was supported by CTC Laboratory Systems Corporation, Tokyo, Japan as a license of Tissue Studio 3 for the DIA. In addition, this study was funded by MEXT KAKENHI (Grant Number 26870597; 2014–2015), JSPS KAKENHI (Grant Number 15H04796), and Tokai University School of Medicine Research Aid (2013–2015). We would like to thank Editage (http://www.editage.jp) for English language editing.
Publisher Copyright:
© The Japanese Breast Cancer Society 2018.
PY - 2018/1/1
Y1 - 2018/1/1
N2 - Background Routine analysis of Ki-67 is not widely recommended for clinical decision-making because of poor reproducibility. Furthermore, counting numerous cells can be laborious for pathologists. Digital image analysis for immunohistochemical analysis was recently developed; however, the clinical efficacy of the Ki-67 index obtained using image analysis is unknown. Methods We retrospectively identified female patients with breast cancer with immunohistochemical Ki-67 and survival data using the pathology database at the Tokai University, Japan. Ki-67 expression was scored by three pathologists. Slides were scanned and converted to virtual slides; Ki-67-positive cells were counted using image analysis. Ki-67 indices obtained by the pathologist’s scoring and image analysis were evaluated by 2 × 2 analysis. Relationships between Ki-67 index and survival outcomes were evaluated using the Kaplan-Meier method and compared using the log-rank test. Results Based on the 2 × 2 analysis, Ki-67 index obtained using image analysis was moderately correlated with the pathologist’s scoring for all patients (κ 0.41; sensitivity, 0.573; specificity, 0.878). Poorer relapse-free survival was associated with high Ki-67 index than with low Ki-67 index for estrogen receptor-positive, human epidermal growth factor receptor 2-negative, and stage I or II patients scored by pathologists (p < 0.001) and obtained using image analysis (p = 0.031). Conclusions The Ki-67 indices obtained using image analysis were moderately correlated with those scored by pathologists. Digital image analysis can be effective for measuring Ki-67 values, because they are associated with relapse-free survival in estrogen receptor-positive, human epidermal growth factor receptor 2-negative, and patients at stage I or II.
AB - Background Routine analysis of Ki-67 is not widely recommended for clinical decision-making because of poor reproducibility. Furthermore, counting numerous cells can be laborious for pathologists. Digital image analysis for immunohistochemical analysis was recently developed; however, the clinical efficacy of the Ki-67 index obtained using image analysis is unknown. Methods We retrospectively identified female patients with breast cancer with immunohistochemical Ki-67 and survival data using the pathology database at the Tokai University, Japan. Ki-67 expression was scored by three pathologists. Slides were scanned and converted to virtual slides; Ki-67-positive cells were counted using image analysis. Ki-67 indices obtained by the pathologist’s scoring and image analysis were evaluated by 2 × 2 analysis. Relationships between Ki-67 index and survival outcomes were evaluated using the Kaplan-Meier method and compared using the log-rank test. Results Based on the 2 × 2 analysis, Ki-67 index obtained using image analysis was moderately correlated with the pathologist’s scoring for all patients (κ 0.41; sensitivity, 0.573; specificity, 0.878). Poorer relapse-free survival was associated with high Ki-67 index than with low Ki-67 index for estrogen receptor-positive, human epidermal growth factor receptor 2-negative, and stage I or II patients scored by pathologists (p < 0.001) and obtained using image analysis (p = 0.031). Conclusions The Ki-67 indices obtained using image analysis were moderately correlated with those scored by pathologists. Digital image analysis can be effective for measuring Ki-67 values, because they are associated with relapse-free survival in estrogen receptor-positive, human epidermal growth factor receptor 2-negative, and patients at stage I or II.
KW - Antigen Ki-67
KW - Breast cancer
KW - Computer-assisted image analysis
KW - Immunohistochemistry
KW - Prognosis
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U2 - 10.1007/s12282-018-0885-1
DO - 10.1007/s12282-018-0885-1
M3 - Article
C2 - 29959636
AN - SCOPUS:85049122285
VL - 25
SP - 768
EP - 777
JO - Breast Cancer
JF - Breast Cancer
SN - 1340-6868
IS - 6
ER -