Apple SK, Lowe AC, Rao PN, Shintaku IP, Moatamed NAComparison of fluorescent in situ hybridization HER-2/neu results on core needle biopsy and excisional biopsy in primary breast cancer. Mod Pathol 22: 1151-1159

Department of Pathology and Laboratory Medicine, David Geffen School of Medicine at UCLA, UCLA Center for the Health Sciences, Los Angeles, CA 90095, USA.
Modern Pathology (Impact Factor: 6.19). 06/2009; 22(9):1151-9. DOI: 10.1038/modpathol.2009.82
Source: PubMed


HER-2/neu status is critical for the therapy for breast carcinoma. Fluorescent in situ hybridization for gene amplification and immunohistochemical stains for protein expression are widely used methods to detect HER-2/neu status. Multiple studies have shown fluorescent in situ hybridization and immunohistochemical stain results to have high concordance rates. To our knowledge, a comparison between fluorescent in situ hybridization results for core needle biopsy and the subsequent excisional biopsy specimens has not yet been studied. We retrospectively evaluated the fluorescence in situ hybridization and immunohistochemical results in both the breast core needle and the excisional biopsy of 125 patients with invasive breast carcinoma from 2002 to 2005. There was complete concordance with respect to both immunohistochemical and fluorescence in situ hybridization results for core needle biopsy and excisional biopsy specimens in 87% of the patients evaluated. Comparison of fluorescent in situ hybridization results of the 129 core needle biopsies to the 131 excisional biopsies of all 125 patients showed a concordance rate of 92%. The immunohistochemical stain results of the same core needle and excisional biopsies showed a concordance rate of 98%. Comparison of the immunohistochemical stain results with the fluorescent in situ hybridization results for all 260 cases examined showed 95% concordance. On the basis of our study, we observed that repeating HER-2/neu testing by immunohistochemical stain and/or fluorescent in situ hybridization methods on excisional biopsy is not unreasonable, in particular in cases of intratumoral heterogeneity, indeterminate/borderline HER-2/neu results and after neoadjuvant chemotherapy.

  • Source
    • "[21-23,28]. The introduction of FISH analysis has improved the concordance rate for HER2 status [22,25]. In the study by Apple et al., the concordance rate of 87% for IHC was improved to 92% by FISH [22]. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Accurate evaluation of human epidermal growth factor receptor type-2 (HER2) status based on core needle biopsy (CNB) specimens is mandatory for identification of patients with primary breast cancer who will benefit from primary systemic therapy with trastuzumab. The aim of the present study was to validate the application of HER2 testing with CNB specimens from primary breast cancers in terms of interobserver reproducibility and comparison with surgically resected specimens. A total of 100 pairs of archival formalin-fixed paraffin-embedded CNB and surgically resected specimens of invasive breast carcinomas were cut into sections. All 100 paired sections were subjected to HER2 testing by immunohistochemistry (IHC) and 27 paired sections were subjected to that by fluorescence in situ hybridization (FISH), the results being evaluated by three and two observers, respectively. Interobserver agreement levels in terms of judgment and the concordance of consensus scores between CNB samples and the corresponding surgically resected specimens were estimated as the percentage agreement and κ statistic. In CNB specimens, the percentage interobserver agreement of HER2 scoring by IHC was 76% (κ = 0.71) for 3 × 3 categories (0-1+ versus 2+ versus 3+) and 90% (κ = 0.80) for 2 × 2 categories (0-2+ versus 3+). These levels were close to the corresponding ones for the surgically resected specimens: 80% (κ = 0.77) for 3 × 3 categories and 92% (κ = 0.88) for 2 × 2 categories. Concordance of consensus for HER2 scores determined by IHC between CNB and the corresponding surgical specimens was 87% (κ = 0.77) for 3 × 3 categories, and 94% (κ = 0.83) for 2 × 2 categories. Among the 13 tumors showing discordance in the mean IHC scores between the CNB and surgical specimens, the results of consensus for FISH results were concordant in 11. The rate of successful FISH analysis and the FISH positivity rate in cases with a HER2 IHC score of 2+ differed among specimens processed at different institutions. It is mandatory to study HER2 on breast cancers, and either CNB or surgical specimen can be used.
    Full-text · Article · Oct 2010 · BMC Cancer
  • [Show abstract] [Hide abstract]
    ABSTRACT: Emerging data show that patients with operable, HER-2/neu overexpressed/amplified breast carcinomas have significantly better responses (more frequently obtaining pathologic complete response and greater percent disease-free survival) when treated with trastuzumab (Herceptin) simultaneously with neoadjuvant chemotherapy than with chemotherapy alone. With the increasing use of neoadjuvant therapies, clinicians require information on biomarkers including HER-2/neu status at the time of needle core biopsy. Concordance rates between fluorescence in situ hybridization (FISH)-determined HER-2/neu status on needle core biopsies and on subsequent excisional biopsies of the same tumor have not been well studied. Moreover, the practice of automatically performing ("reflexing") 2+ immunohistochemical (IHC) staining needle core biopsies for FISH analysis on the same sample needs to be validated. In this study, we set out to (1) determine the accuracy of HER-2/neu status as determined by FISH on needle core biopsy material compared with FISH on the subsequent excisional biopsy of the same tumor with special consideration of IHC 2+staining cases and (2) determine the constancy of HER-2/neu status in pre-neoadjuvant and post-neoadjuvant chemotherapy-treated tumor in the form of needle core biopsy and excisional biopsy samples, respectively. 100 patients whose needle core biopsies and subsequent excisional biopsy samples were pathologically evaluated at our institution were studied. For each patient, unstained sections from both specimens were prepared and used for IHC or FISH. IHC was carried out using the HercepTest kit (DAKO, Carpinteria, CA). Parallel unstained slides were used to carry out FISH (dual probe, Vysis). Statistical analyses were carried out on the resulting data generated after interpretation. The concordance rate between FISH results determined on the needle core biopsy and subsequent excisional biopsy of the same tumor was 86% (kappa=0.56, P=2x10). If equivocal FISH cases (> or =1.8 to < or =2.2 amplification ratio) in a needle core biopsy or excisional biopsy specimen or both, were excluded, the concordance rate increased to 95% (kappa coefficient=0.86, P=2x10). Fourteen of 100 (14%) cases showed 2+ IHC staining in the needle core biopsy specimen with good concordance of FISH-determined HER-2/neu status between the needle core biopsy and excisional biopsy specimens (79% agreement and kappa=0.512, P=0.05). Nine, 3, and 2 cases of the 14 cases were amplified, equivocal, and negative on the excisional biopsy specimens, respectively. Of the 15 patients who received neoadjuvant chemotherapy, 93% and 87% had no change in HER-2/neu status as determined by IHC or FISH, respectively, in the excisional biopsy specimen when compared with that determined on the prior core biopsy sample. Excellent overall concordance was achieved between FISH-determined HER-2/neu status on the needle core biopsy and that determined on the subsequent excisional biopsy of the same tumor. These results suggest that intratumoral heterogeneity of HER-2/neu assessed by FISH is not a significant confounding factor when analyzing smaller sized samples. Furthermore, 79% of 2+IHC staining needle core biopsy cases showed concordant FISH results in the needle core biopsy and subsequent excisional biopsy specimens. Our results show good concordance, however, larger cohorts need to be studied to verify this finding. HER-2/neu status remains unchanged in the majority of cases when comparing pre-neoadjuvant and post-neoadjuvant chemotherapy-treated specimens.
    No preview · Article · Mar 2010 · The American journal of surgical pathology
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Core needle biopsies (CNBs) are widely used to determine human epidermal growth factor receptor 2 (HER2) status in breast cancer. Recent publications reported up to 20% false-positive results on CNBs if immunohistochemistry (IHC) is compared with fluorescent in situ hybridization (FISH). To clarify, if confirmation of IHC positivity by FISH is generally required, we analyzed the reliability of IHC positivity on CNBs versus surgical specimens in a multi-institutional study. Five pathologic laboratories contributed to this study by performing IHC on 500 CNBs and the corresponding surgical specimens overall. If IHC revealed score 2+ or 3+, HER2 status was confirmed by FISH in a central laboratory. We compared evaluation according to US Food and Drug Administration-approved scoring criteria and recently published American Society of Clinical Oncology (ASCO)-College of American Pathologists (CAP) guidelines. CNBs scored 3+ revealed five false-positive results if scoring followed the US Food and Drug Administration criteria (five of 40; 12.5%) and two false-positives in terms of the ASCO-CAP criteria (two of 33; 6.1%). IHC was false negative in one CNB only. By contrast, IHC on surgical specimens revealed five false-negative results, but only one false-positive result (one of 35; 2.9%) if scored following US Food and Drug Administration-approved criteria. With the aid of the ASCO-CAP criteria, false-positive IHC results were obtained in only one of the five participating institutions. IHC 3+ scores on CNBs proved to be reliable in four of the five participating institutions if scoring followed the ASCO-CAP criteria. Therefore, accurate determination of HER2 status in breast cancer is possible on CNB using the common strategy to screen all cases by IHC and retest only 2+ scores by FISH. Prerequisites are quality assurance and the application of the new ASCO-CAP criteria.
    Full-text · Article · May 2010 · Journal of Clinical Oncology
Show more