In the published article, there was an error in the legends for Figures 1–4, as published. The legends incorrectly refer to “Four invasive ductal carcinomas,” each figure should instead refer to just one invasive carcinoma. The corrected legends appear below.
An invasive carcinoma of the breast tested for; (A) estrogen receptors, (B) progesterone receptors, (C) human epidermal growth factor receptor-2, (D) Ki-67 proliferating antigen. Following immunohistochemical testing and scoring by all ten participating laboratories, the median scores for the tumor were; (A, ER 0), (B PR 0), (C HER2 3+), (D Ki67 40%). Magnification ×20 (all images).
Histological images of invasive breast carcinomas that were tested by immunohistochemistry. The tumors show differing levels of protein expression for estrogen receptors (ER), progesterone receptors (PR), human epidermal growth factor receptor-2 (HER2) and Ki67.
An invasive carcinoma of the breast tested for; (A) estrogen receptors, (B) progesterone receptors, (C) human epidermal growth factor receptor-2, (D) Ki-67 proliferating antigen. Following immunohistochemical testing and scoring by all ten participating laboratories, the median scores for the tumor were; (A, ER 0), (B PR 0), (C HER2 1+), (D Ki67 23%). Magnification ×20 (all images).
Histological images of invasive breast carcinomas that were tested by immunohistochemistry. The tumors show differing levels of protein expression for estrogen receptors (ER), progesterone receptors (PR), human epidermal growth factor receptor-2 (HER2) and Ki67.
An invasive carcinoma of the breast tested for; (A) estrogen receptors, (B) progesterone receptors, (C) human epidermal growth factor receptor-2, (D) Ki-67 proliferating antigen. Following immunohistochemical testing and scoring by all ten participating laboratories, the median scores for the tumor were; (A, ER 8), (B PR 5), (C HER2 1+), (D Ki67 10%). Magnification ×20 (all images).
Histological images of invasive breast carcinomas that were tested by immunohistochemistry. The tumors show differing levels of protein expression for estrogen receptors (ER), progesterone receptors (PR), human epidermal growth factor receptor-2 (HER2) and Ki67.
An invasive carcinoma of the breast tested for; (A) estrogen receptors, (B) progesterone receptors, (C) human epidermal growth factor receptor-2, (D) Ki-67 proliferating antigen. Following immunohistochemical testing and scoring by all ten participating laboratories, the median scores for each tumor were; (A ER 8), (B PR 8), (C HER2 0), (D Ki67 2%). Magnification ×20 (all images).
Histological images of invasive breast carcinomas that were tested by immunohistochemistry. The tumors show differing levels of protein expression for estrogen receptors (ER), progesterone receptors (PR), human epidermal growth factor receptor-2 (HER2) and Ki67.
In the published article, the reference for Do, Whittaker and David, 2024 was incorrectly listed as reference number 37, and the reference for GLOBOCAN, 2022 was incorrectly listed as reference number 38. These should be reversed.
A correction has been made to Materials and Methods, Tissue Samples. At the end of the sentence “It was recommended that fixation time should not be shorter than 8 h and no longer than 48 h”, reference 22 was erroneously cited, instead reference 21 should be cited.
A correction has also been made to section Materials and Methods, Inter-Laboratory Testing. At the end of the sentence “Allred Score of 4, 5, 6, 7, or 8 are essentially equivalent in their reliability of predicting a favorable response to hormonal therapies” reference 21 was erroneously cited, instead reference 22 should be cited.
The authors apologize for these error and state that this does not change the scientific conclusions of the article in any way. The original article has been updated.
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