TY - JOUR
T1 - The increasing importance of histologic grading in tailoring adjuvant systemic therapy in 30,843 breast cancer patients
AU - van Dooijeweert, C.
AU - Baas, I. O.
AU - Deckers, I. A.G.
AU - Siesling, S.
AU - van Diest, P. J.
AU - van der Wall, E.
N1 - Funding Information:
The authors thank the registration team of the Netherlands Comprehensive Cancer Organization (IKNL) for the collection of data for the NCR as well as IKNL staff for scientific advice.
Funding Information:
This study was supported by the Quality Foundation of the Dutch Association of Medical Specialists (SKMS). Funding was obtained by PD. Role of the funding source The funding source had no role in the design and conduct of this study, nor did it have a role in the review or approval of the manuscript and the decision to submit the manuscript for publication.
Publisher Copyright:
© 2021, The Author(s).
PY - 2021/6
Y1 - 2021/6
N2 - Purpose: The large variation in histologic grading of invasive breast cancer (IBC) that has been reported likely influences tailoring adjuvant therapy. The role of grading in therapeutic decision-making in daily practice, was evaluated using the Dutch national guidelines for IBC-management. Methods: Synoptic reports of IBC resection-specimens, obtained between 2013 and 2016, were extracted from the nationwide Dutch Pathology Registry, and linked to treatment-data from the Netherlands Cancer Registry. The relevance of grading for adjuvant chemotherapy (aCT) was quantified by identifying patients for whom grade was the determinative factor. In addition, the relation between grade and aCT-administration was evaluated by multivariate logistic regression for patients with a guideline-aCT-indication. Results: 30,843 patients were included. Applying the guideline that was valid between 2013 and 2016, grade was the determinative factor for the aCT-indication in 7744 (25.1%) patients, a percentage that even increased according to the current guideline where grade would be decisive for aCT in 10,869 (35.2%) patients. Also in current practice, the indication for adjuvant endocrine therapy (aET) would be based on grade in 9173 (29.7%) patients. Finally, as patients with lower-grade tumors receive aCT significantly less often, grade was also decisive in tailoring aCT de-escalation. Conclusions: In the largest study published so far we illustrate the increasing importance of histologic grade in tailoring adjuvant systemic breast cancer therapy. Next to playing a key-role in aCT-indication and de-escalation, the role of grading has expanded to the indication for aET. Optimizing histologic grading by pathologists is urgently needed to diminish the risk of worse patient outcome due to non-optimal treatment.
AB - Purpose: The large variation in histologic grading of invasive breast cancer (IBC) that has been reported likely influences tailoring adjuvant therapy. The role of grading in therapeutic decision-making in daily practice, was evaluated using the Dutch national guidelines for IBC-management. Methods: Synoptic reports of IBC resection-specimens, obtained between 2013 and 2016, were extracted from the nationwide Dutch Pathology Registry, and linked to treatment-data from the Netherlands Cancer Registry. The relevance of grading for adjuvant chemotherapy (aCT) was quantified by identifying patients for whom grade was the determinative factor. In addition, the relation between grade and aCT-administration was evaluated by multivariate logistic regression for patients with a guideline-aCT-indication. Results: 30,843 patients were included. Applying the guideline that was valid between 2013 and 2016, grade was the determinative factor for the aCT-indication in 7744 (25.1%) patients, a percentage that even increased according to the current guideline where grade would be decisive for aCT in 10,869 (35.2%) patients. Also in current practice, the indication for adjuvant endocrine therapy (aET) would be based on grade in 9173 (29.7%) patients. Finally, as patients with lower-grade tumors receive aCT significantly less often, grade was also decisive in tailoring aCT de-escalation. Conclusions: In the largest study published so far we illustrate the increasing importance of histologic grade in tailoring adjuvant systemic breast cancer therapy. Next to playing a key-role in aCT-indication and de-escalation, the role of grading has expanded to the indication for aET. Optimizing histologic grading by pathologists is urgently needed to diminish the risk of worse patient outcome due to non-optimal treatment.
KW - Adjuvant systemic treatment
KW - Guideline adherence
KW - Histologic grade
KW - Invasive breast cancer
KW - Real-world data
UR - http://www.scopus.com/inward/record.url?scp=85099935814&partnerID=8YFLogxK
U2 - 10.1007/s10549-021-06098-7
DO - 10.1007/s10549-021-06098-7
M3 - Article
C2 - 33517555
AN - SCOPUS:85099935814
SN - 0167-6806
VL - 187
SP - 577
EP - 586
JO - Breast cancer research and treatment
JF - Breast cancer research and treatment
IS - 2
ER -