%0 Journal Article
%T Can Histological Grade and Mitotic Index Replace Ki67 to Determine Luminal Breast Cancer Subtypes?
%J Asian Pacific Journal of Cancer Prevention
%I West Asia Organization for Cancer Prevention (WAOCP), APOCP's West Asia Chapter.
%Z 1513-7368
%A Oddo, David
%A Pulgar, Dahiana
%A Elgueta, Nicole
%A Acevedo, Francisco
%A Razmilic, Dravna
%A Navarro, Maria Elena
%A Camus, Mauricio
%A Merino, Tomas
%A Retamal, Ignacio
%A Perez-Sepulveda, Alejandra
%A Villarroel, Alejandra
%A Galindo, Hector
%A Peña, José
%A sanchez, cesar
%D 2018
%\ 01/01/2018
%V 19
%N 1
%P 179-183
%! Can Histological Grade and Mitotic Index Replace Ki67 to Determine Luminal Breast Cancer Subtypes?
%K Breast Neoplasms
%K Ki67 antigen
%K mitotic index
%K histology
%R 10.22034/APJCP.2018.19.1.179
%X 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.
%U https://journal.waocp.org/article_55094_ada2e78b63233f99641fe5ef1d851eef.pdf