TY - JOUR
T1 - Can histological grade and mitotic index replace Ki67 to determine luminal breast cancer subtypes?
AU - Oddó, David
AU - Pulgar, Dahiana
AU - Elgueta, Nicole
AU - Acevedo, Francisco
AU - Razmiliz, Dravna
AU - Navarro, María Elena
AU - Camus, Mauricio
AU - Merino, Tomás
AU - Retamal, Ignacio
AU - Pérez-Sepúlveda, Alejandra
AU - Villarroel, Alejandra
AU - Galindo, Héctor
AU - Peña, José
AU - Sánchez, César
PY - 2018/1/1
Y1 - 2018/1/1
N2 - Introduction: Breast cancer can be classified into subtypes based on immunohistochemical markers, with Ki67 expression levels being used to divide luminal BC tumors in luminal A and B subtypes; however, Ki67 is not routinely determined due to a lack of standardization. Objective: To evaluate histological grade and Eliminate: the mitotic index to determine if they can be used as an alternative method to Ki67 staining for luminal subtype definition. Methods: We evaluated estrogen receptor positive breast cancer tissue samples. Pathological analysis included determination of Ki67. A low level of Ki67 was defined as < 14% positive cells. Results: We evaluated 151 breast cancer samples; 24 (15,9%) were classified as I; 74 as HG II (49%), and 53 (35,1%) as HG III. The median value for Ki67 was 13% (range: < 1% - 82%) and for MI was 2 (0-12). Histological grade I tumors exhibited Ki67 values significantly lower than HG II and III tumors (Anova, Tamhane test p=0,001). A higher Ki67 value was related to a higher MI (Rho Sperman p=0,336; R2= 0,0273). ROC curve analysis determined that a MI ≥ 3 had a sensibility of 61.9% and specificity of 66.7% in predicting a high Ki67 value (≥14%) (area under the curve: 0,691; p =0,0001). A HG I tumor or HG II-III with MI ≤2, had a high probability of corresponding to a LA tumor (76,3%), as defined using Ki67 expression, while the probability of a LB subtype was higher with HG II-III and a MI ≥3 (57.4%). Global discrimination was 68.1%. Conclusions: For the LA subtype, our predictive model showed a good correlation of HG and MI with the classification based on Ki67 < 14%. In the LB subtype, the model showed a weak correlation; therefore Ki67 determination seems to be needed for this group of patients.
AB - Introduction: Breast cancer can be classified into subtypes based on immunohistochemical markers, with Ki67 expression levels being used to divide luminal BC tumors in luminal A and B subtypes; however, Ki67 is not routinely determined due to a lack of standardization. Objective: To evaluate histological grade and Eliminate: the mitotic index to determine if they can be used as an alternative method to Ki67 staining for luminal subtype definition. Methods: We evaluated estrogen receptor positive breast cancer tissue samples. Pathological analysis included determination of Ki67. A low level of Ki67 was defined as < 14% positive cells. Results: We evaluated 151 breast cancer samples; 24 (15,9%) were classified as I; 74 as HG II (49%), and 53 (35,1%) as HG III. The median value for Ki67 was 13% (range: < 1% - 82%) and for MI was 2 (0-12). Histological grade I tumors exhibited Ki67 values significantly lower than HG II and III tumors (Anova, Tamhane test p=0,001). A higher Ki67 value was related to a higher MI (Rho Sperman p=0,336; R2= 0,0273). ROC curve analysis determined that a MI ≥ 3 had a sensibility of 61.9% and specificity of 66.7% in predicting a high Ki67 value (≥14%) (area under the curve: 0,691; p =0,0001). A HG I tumor or HG II-III with MI ≤2, had a high probability of corresponding to a LA tumor (76,3%), as defined using Ki67 expression, while the probability of a LB subtype was higher with HG II-III and a MI ≥3 (57.4%). Global discrimination was 68.1%. Conclusions: For the LA subtype, our predictive model showed a good correlation of HG and MI with the classification based on Ki67 < 14%. In the LB subtype, the model showed a weak correlation; therefore Ki67 determination seems to be needed for this group of patients.
KW - Breast neoplasms
KW - Histology
KW - Ki67 antigen
KW - Mitotic index
UR - http://www.scopus.com/inward/record.url?scp=85040964002&partnerID=8YFLogxK
U2 - 10.22034/APJCP.2018.19.1.179
DO - 10.22034/APJCP.2018.19.1.179
M3 - Article
C2 - 29373911
AN - SCOPUS:85040964002
SN - 1513-7368
VL - 19
SP - 179
EP - 183
JO - Asian Pacific Journal of Cancer Prevention
JF - Asian Pacific Journal of Cancer Prevention
IS - 1
ER -