Correlation of clinicopathologic features of Filipino primary breast cancer patients with HER2 Subgroups classified according to the ASCO/CAP 2018 breast cancer HER2 testing guidelines

Background@#Guidelines for testing human epidermal growth factor receptor 2 (HER2) in breast cancer using fluorescence in situ hybridization (FISH) were released in 2018. These guidelines were jointly developed by the American Society of Clinical Oncology (ASCO) and the College of American Pathologists (CAP) to achieve a clearer designation of breast cancer HER2 status. Clinical correlation with other factors was also considered appropriate, especially for those cases classified under ISH groups 2, 3, and 4.@*Objective@#In this study, we examined clinicopathologic features among Filipino breast cancer patients whose HER2 status was reclassified based on the 2018 ASCO/CAP guidelines.@*Methodology@#One hundred and thirty-two (132) breast cancer cases with immunohistochemistry (IHC) equivocal results in the Medical City were enrolled from January 2017 up to December 2020. HER2 FISH results classified under groups 2, 3, and 4 were then re-evaluated for HER2-IHC status in accordance with the 2018 ASCO/CAP guidelines. The relationship between clinicopathologic features and HER2 status was analyzed using the Fisher exact test.@*Results@#Significant differences were found in histologic type, nuclear pleomorphism, mitotic rate, progesterone receptor (PR) status, and regional lymph node involvement among the reclassified ISH groups. In the conv+ group, the tumor cells did not involve the regional lymph nodes as compared to group 5, where the tumor cells were involved. The conv- group had a higher grade for nuclear pleomorphism, mitotic count, and overall Nottingham Histologic Grade than group 5. There was a significant association between progesterone receptors among the conv- group and group 1.@*Conclusion@#Filipino breast cancer cases whose HER2 status was reclassified to negative following the 2018 ASCO/CAP guidelines had statistically different clinicopathologic features from those classified as group 5.

Concordance between core needle biopsy and surgical specimen for oestrogen receptor, progesterone receptor and human epidermal growth factor receptor 2 status in breast cancer

<p><b>INTRODUCTION</b>This study aimed to analyse the concordance rate, sensitivity, specificity, positive predictive value (PPV) and negative predictive value of core needle biopsy (CNB) and subsequent surgical specimen (SS) in assessing levels of oestrogen receptor (ER), progesterone receptor (PgR) and human epidermal growth factor receptor 2 (HER2/neu). It also evaluated the revised American Society of Clinical Oncology/College of American Pathologists (ASCO/CAP) guidelines for ER/PgR positivity.</p><p><b>METHODS</b>We analysed the breast cancer database of KK Women's and Children's Hospital, Singapore, from 1 June 2005 to 30 December 2012. Invasive breast cancer patients who had CNB and subsequent SS were included.</p><p><b>RESULTS</b>A total of 560 patients were included. The concordance of ER, PgR and HER2/neu positivity between CNB and SS was 96.1%, 89.1% and 96.8%, respectively. When the 'ER ≥ 10% positive' group was compared with the 'ER ≥ 1% positive' group, specificity increased from 79.7% to 92.5% and PPV increased from 93.9% to 97.5%. When the 'PgR ≥ 10% positive' group was compared with the 'PgR ≥ 1% positive' group, specificity increased from 84.2% to 89.3% and PPV improved from 89.7% to 92.9%. The revised ASCO/CAP guidelines decreased discordant results by > 50% for ER and by 18.2% for PgR.</p><p><b>CONCLUSION</b>CNB has high concordance with SS in the evaluation of the molecular profile of invasive breast cancer. Thus, molecular evaluation does not need to be repeated with SS except for ER-, PgR- and HER2/neu-negative CNB results. The revised ASCO/CAP guidelines resulted in more precise ER and PgR status on CNB.</p>

Comparison of the FDA and ASCO/CAP Criteria for HER2 Immunohistochemistry in Upper Urinary Tract Urothelial Carcinoma

BACKGROUND: Human epidermal growth factor receptor 2 (HER2) is one of the known oncogenes in urothelial carcinoma. However, the association between HER2 and the prognosis of upper urinary tract urothelial carcinoma (UUTUC) has not yet been fully clarified. The aim of this study was to evaluate HER2 expression using the United States Food and Drug Administration (FDA) criteria and American Society of Clinical Oncology/College of American Pathologists (ASCO/CAP) criteria and compare their prognostic significance in UUTUC. METHODS: HER2 expression was evaluated in 144 cases of UUTUC by immunohistochemistry (IHC) using tissue microarrays. We separately analyzed HER2 expression using the FDA and ASCO/CAP criteria. The IHC results were categorized into low (0, 1+) and high (2+, 3+) groups. RESULTS: Using the FDA criteria, 94 cases were negative, 38 cases were 1+, nine cases were 2+, and three cases were 3+. Using the ASCO/CAP criteria, 94 cases were negative, 34 cases were 1+, 13 cases were 2+, and three cases were 3+. Four cases showing 2+ according to the ASCO/CAP criteria were reclassified as 1+ by the FDA criteria. High HER2 expression by both the FDA criteria and ASCO/CAP criteria was significantly associated with International Society of Urological Pathology high grade (p = .001 and p < .001). The high HER2 expression group classified with the FDA criteria showed significantly shorter cancer-specific survival (p = .004), but the HER2 high and low expression groups classified with the ASCO/CAP criteria did not show significant differences (p = .161) in cancer-specific survival. CONCLUSIONS: HER2 high expression groups were significantly associated with shorter cancer-specific survival, and our study revealed that the FDA criteria are more suitable for determining HER2 expression in UUTUC.