HER2 Testing Characteristics Can Predict Residual Cancer Burden following Neoadjuvant Chemotherapy in HER2-Positive Breast Cancer

Objectives. The response to HER2-targeted neoadjuvant chemotherapy (NAC) in HER2-positive (+) breast cancer can be quantified using residual cancer burden (RCB) pathologic evaluation to predict relapse free/overall survival. However, more information is needed to characterize the relationship betwee...

Full description

Saved in:
Bibliographic Details
Main Authors: Tamera J. Lillemoe, Mara Rendi, Michaela L. Tsai, Monica Knaack, Rina Yarosh, Erin Grimm, Barbara Susnik, Janet Krueger, Susan Olet, Karen K. Swenson
Format: Article
Language:English
Published: Wiley 2021-01-01
Series:International Journal of Breast Cancer
Online Access:http://dx.doi.org/10.1155/2021/6684629
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1849685929047883776
author Tamera J. Lillemoe
Mara Rendi
Michaela L. Tsai
Monica Knaack
Rina Yarosh
Erin Grimm
Barbara Susnik
Janet Krueger
Susan Olet
Karen K. Swenson
author_facet Tamera J. Lillemoe
Mara Rendi
Michaela L. Tsai
Monica Knaack
Rina Yarosh
Erin Grimm
Barbara Susnik
Janet Krueger
Susan Olet
Karen K. Swenson
author_sort Tamera J. Lillemoe
collection DOAJ
description Objectives. The response to HER2-targeted neoadjuvant chemotherapy (NAC) in HER2-positive (+) breast cancer can be quantified using residual cancer burden (RCB) pathologic evaluation to predict relapse free/overall survival. However, more information is needed to characterize the relationship between patterns of HER2 testing results and response to NAC. We evaluated clinicopathologic characteristics associated with RCB categories in HER2+ patients who underwent HER2-directed NAC. Methods. A retrospective chart review was conducted with Stage I–III HER2+ breast cancer cases following NAC and surgical resection. HER2 immunohistochemistry (IHC) staining and fluorescence in situ hybridization (FISH), histologic/clinical characteristics, hormone receptor status, and RCB scores (RCB-0, RCB-I, RCB-II, and RCB-III) were evaluated. Results. 64/151 (42.4%) patients with HER2+ disease had pathologic complete response (pCR). Tumors with suboptimal response (RCB-II and RCB-III) were more likely to demonstrate less than 100% HER2 IHC 3+ staining (p<0.0001), lower HER2 FISH copies (p<0.0001), and lower HER2/CEP17 ratios (p=0.0015) compared to RCB-I and RCB-II responses. Estrogen receptor classification using ≥10% versus ≥1% staining showed greater association with higher RCB categories. Conclusions. HER2+ characteristics show differing response to therapy despite all being categorized as positive; tumors with less than 100% IHC 3+ staining, lower HER2 FISH copies, and lower HER2/CEP17 ratios resulted in higher RCB scores.
format Article
id doaj-art-bb78fc25820f448b871f0e9180395daa
institution DOAJ
issn 2090-3170
2090-3189
language English
publishDate 2021-01-01
publisher Wiley
record_format Article
series International Journal of Breast Cancer
spelling doaj-art-bb78fc25820f448b871f0e9180395daa2025-08-20T03:22:54ZengWileyInternational Journal of Breast Cancer2090-31702090-31892021-01-01202110.1155/2021/66846296684629HER2 Testing Characteristics Can Predict Residual Cancer Burden following Neoadjuvant Chemotherapy in HER2-Positive Breast CancerTamera J. Lillemoe0Mara Rendi1Michaela L. Tsai2Monica Knaack3Rina Yarosh4Erin Grimm5Barbara Susnik6Janet Krueger7Susan Olet8Karen K. Swenson9Allina Health Laboratory-Hospital Pathology Associates, 800 East 28th Street, Minneapolis, MN 55407, USAAllina Health Laboratory-Hospital Pathology Associates, 800 East 28th Street, Minneapolis, MN 55407, USAAllina Health System, Virginia Piper Cancer Institute Clinical Research Program, 800 East 28th Street, Minneapolis, MN 55407, USAAllina Health System, Virginia Piper Cancer Institute Clinical Research Program, 800 East 28th Street, Minneapolis, MN 55407, USAAllina Health System, Virginia Piper Cancer Institute Clinical Research Program, 800 East 28th Street, Minneapolis, MN 55407, USAAllina Health Laboratory-Hospital Pathology Associates, 800 East 28th Street, Minneapolis, MN 55407, USAAllina Health Laboratory-Hospital Pathology Associates, 800 East 28th Street, Minneapolis, MN 55407, USAAllina Health System, Virginia Piper Cancer Institute Clinical Research Program, 800 East 28th Street, Minneapolis, MN 55407, USAAllina Health System, Research Informatics, 925 Chicago Avenue, Minneapolis, MN 55407, USAAllina Health System, Virginia Piper Cancer Institute Clinical Research Program, 800 East 28th Street, Minneapolis, MN 55407, USAObjectives. The response to HER2-targeted neoadjuvant chemotherapy (NAC) in HER2-positive (+) breast cancer can be quantified using residual cancer burden (RCB) pathologic evaluation to predict relapse free/overall survival. However, more information is needed to characterize the relationship between patterns of HER2 testing results and response to NAC. We evaluated clinicopathologic characteristics associated with RCB categories in HER2+ patients who underwent HER2-directed NAC. Methods. A retrospective chart review was conducted with Stage I–III HER2+ breast cancer cases following NAC and surgical resection. HER2 immunohistochemistry (IHC) staining and fluorescence in situ hybridization (FISH), histologic/clinical characteristics, hormone receptor status, and RCB scores (RCB-0, RCB-I, RCB-II, and RCB-III) were evaluated. Results. 64/151 (42.4%) patients with HER2+ disease had pathologic complete response (pCR). Tumors with suboptimal response (RCB-II and RCB-III) were more likely to demonstrate less than 100% HER2 IHC 3+ staining (p<0.0001), lower HER2 FISH copies (p<0.0001), and lower HER2/CEP17 ratios (p=0.0015) compared to RCB-I and RCB-II responses. Estrogen receptor classification using ≥10% versus ≥1% staining showed greater association with higher RCB categories. Conclusions. HER2+ characteristics show differing response to therapy despite all being categorized as positive; tumors with less than 100% IHC 3+ staining, lower HER2 FISH copies, and lower HER2/CEP17 ratios resulted in higher RCB scores.http://dx.doi.org/10.1155/2021/6684629
spellingShingle Tamera J. Lillemoe
Mara Rendi
Michaela L. Tsai
Monica Knaack
Rina Yarosh
Erin Grimm
Barbara Susnik
Janet Krueger
Susan Olet
Karen K. Swenson
HER2 Testing Characteristics Can Predict Residual Cancer Burden following Neoadjuvant Chemotherapy in HER2-Positive Breast Cancer
International Journal of Breast Cancer
title HER2 Testing Characteristics Can Predict Residual Cancer Burden following Neoadjuvant Chemotherapy in HER2-Positive Breast Cancer
title_full HER2 Testing Characteristics Can Predict Residual Cancer Burden following Neoadjuvant Chemotherapy in HER2-Positive Breast Cancer
title_fullStr HER2 Testing Characteristics Can Predict Residual Cancer Burden following Neoadjuvant Chemotherapy in HER2-Positive Breast Cancer
title_full_unstemmed HER2 Testing Characteristics Can Predict Residual Cancer Burden following Neoadjuvant Chemotherapy in HER2-Positive Breast Cancer
title_short HER2 Testing Characteristics Can Predict Residual Cancer Burden following Neoadjuvant Chemotherapy in HER2-Positive Breast Cancer
title_sort her2 testing characteristics can predict residual cancer burden following neoadjuvant chemotherapy in her2 positive breast cancer
url http://dx.doi.org/10.1155/2021/6684629
work_keys_str_mv AT tamerajlillemoe her2testingcharacteristicscanpredictresidualcancerburdenfollowingneoadjuvantchemotherapyinher2positivebreastcancer
AT mararendi her2testingcharacteristicscanpredictresidualcancerburdenfollowingneoadjuvantchemotherapyinher2positivebreastcancer
AT michaelaltsai her2testingcharacteristicscanpredictresidualcancerburdenfollowingneoadjuvantchemotherapyinher2positivebreastcancer
AT monicaknaack her2testingcharacteristicscanpredictresidualcancerburdenfollowingneoadjuvantchemotherapyinher2positivebreastcancer
AT rinayarosh her2testingcharacteristicscanpredictresidualcancerburdenfollowingneoadjuvantchemotherapyinher2positivebreastcancer
AT eringrimm her2testingcharacteristicscanpredictresidualcancerburdenfollowingneoadjuvantchemotherapyinher2positivebreastcancer
AT barbarasusnik her2testingcharacteristicscanpredictresidualcancerburdenfollowingneoadjuvantchemotherapyinher2positivebreastcancer
AT janetkrueger her2testingcharacteristicscanpredictresidualcancerburdenfollowingneoadjuvantchemotherapyinher2positivebreastcancer
AT susanolet her2testingcharacteristicscanpredictresidualcancerburdenfollowingneoadjuvantchemotherapyinher2positivebreastcancer
AT karenkswenson her2testingcharacteristicscanpredictresidualcancerburdenfollowingneoadjuvantchemotherapyinher2positivebreastcancer