Wiktor, Anne E.

e11527 Background: 118 Her2 positive invasive carcinomas were retested centrally at the Mayo Clinic for Her2 status confirmation prior to inclusion in Mayo Clinic Cancer Research Consortium study RC0639 phase II study of cardiac safety and tolerability of adjuvant chemotherapy plus trastuzumab with lapatinib for resected Her2+ breast cancer (MCCRC RC0639). Methods: Central confirmatory methods were immunohistochemical (IHC) Dako HercepTest on a Dako Autostainer using the manufacturer's recommendations and HercepTest kit epitrope retrieval kit and fluorescent in situ hybridization (FISH) using Vysis PathVysion probe kit. Test results are interpreted using ASCO/CAP guidelines (IHC >30%, Her2:CEP 17 ratio >2.2). Results: There is local and central test 3+ IHC concordance in 48 of 53 tumors (agreement 90.6%) and FISH amplification in 29 of 33 tumors (agreement 87.9%), improved or similar results using identical methods to results in NCCTG N9831 adjuvant trial (n=1063, 81.6% IHC; n=813, 88.1% FISH). Of 92 centrally tested 3+ IHC positive tumors, 88 (95.7%) were FISH amplified. 5 centrally tested patients interpreted as Her2 positive by pre-ASCO/CAP guidelines (IHC >10%; HER2:CEP17 ratio >2) are Her2 ineligible using ASCO/CAP guidelines. IHC not confirmed centrally was reviewed by a second pathologist in 16 of 118 specimens. IHC concordance between two central pathologists was 10/16 (62.5%) in negative or equivocal (≤30% IHC staining) specimens; 7/10 (70%) with two reader agreement were FISH amplified and 4/6 (66%) with disagreement were FISH amplified. Conclusions: Concordance in IHC and FISH results between local and central labs is similar or improved since N9831. New ASCO/CAP Her2 testing guidelines change eligibility based on Her2 status in 4.2 % of patients. Equivocal IHC results falling between pre- and post- ASCO/CAP IHC positive thresholds (>10% and <30% IHC strong staining) are only partially resolved by repeat IHC review and/or FISH testing. No significant financial relationships to disclose.

4071 Background: Selection of patients for HER2-targeted therapy is based on HER2 analysis in primary EACs. Since EACs metastasize via regional lymph nodes, concordance of HER2 gene amplification results between primary tumors and their metastatic lymph nodes (MLN) is a clinically important issue. Methods: Resected EACs (N = 103) having at least three distinct regional MLNs (total 508 MLNs; median 4 [range 3-11]) were sectioned using routine procedures and tested for HER2 amplification by fluorescence in situ hybridization (FISH). Primary tumors were also evaluated for HER2 protein expression by immunohistochemistry (IHC) and by FISH. Amplification was defined as HER2/CEP17 ≥ 2. IHC was scored as 0, 1+, 2+, or 3+. Primaries whose HER2 status was positive by both FISH and IHC (ie, amplified and IHC3+), or negative by both (ie, nonamplified and IHC0-1+), were selected. HER2 status was compared between primaries and their MLNs (kappa). Results: Concordant HER2 results between primaries and their MLNs were found in 92% (95/103) of EACs (Table; κ = .76 [95% CI .60 - .92]). However, among patients with HER2-positive primaries, 19% (4/21) had HER2-nonamplified MLNs; among these cases, either all MLNs were HER2-nonamplified (n = 2), or both HER2-nonamplified and –amplified MLNs were present (n = 2). Among HER2-negative primary EACs, 5% (4/82) of cases had MLNs that were all HER2-amplified (n = 3) or both HER2-nonamplified and -amplified (n = 1). Conclusions: A patient subset whose primary EACs were HER2-positive (by both FISH and IHC) were unexpectedly found to lack HER2 amplification in corresponding MLNs. Conversely, a subgroup with HER2-negative primaries had HER2-amplified MLNs, and would have been deemed ineligible for HER2-targeted therapy. These preliminary data suggest that evaluating MLNs in resected EACs has the potential to better identify patients who benefit from HER2-targeted therapy. [Table: see text]

4009 Background: HER2 expression in upper digestive cancer is reported to be heterogeneous, which substantially affects interpretation of HER2 positivity in the clinic. Yet the frequency and prognostic impact of HER2 genetic heterogeneity and polysomy 17 (poly17) are unknown in EAC. Methods: HER2 amplification (fluorescence in situ hybridization) and protein expression were examined in untreated surgical EAC specimens (N = 661) at Mayo Clinic. HER2 genetic heterogeneity was defined per ASCO/CAP as amplification (HER2/CEP17 ratio ≥ 2) in 5-50% of cancer cells; poly17 refers to ≥ 3 copies of chromosome 17. Most tumors were T3-4 (68%) or lymph node (LN)-positive (73%). Cox models were used to assess disease-specific (DSS) and overall survival (OS). Results: HER2 amplification was detected in 117 of 661 EACs (18%), of which 20 (17%) showed HER2 heterogeneity. HER2 heterogeneous tumors had a significantly higher frequency of poly17 and high tumor grade. HER2 heterogeneity by amplification vs expression were correlated. Since heterogeneity was limited to HER2-amplified tumors, survival analysis was stratified by amplification status. In multivariable analysis, only HER2 heterogeneity and metastatic LN number were prognostic (Table). Conclusions: Among HER2 amplified EACs, 17% show HER2 heterogeneity, which is associated with increased poly17 and independently predicts 2-fold higher risk of cancer-specific death. Among HER2-nonamplified cases, poly17 is independently associated with worse survival. These novel findings demonstrate aggressive subgroups in HER2-amplified and -nonamplified EACs that have important implications for HER2 analysis and evaluation of benefit from HER2 targeted therapy. [Table: see text]

7055 Introduction: Cytogenetic abnormalities have been shown to be the most important determinant of prognosis in patients with acute myeloid leukemia (AML). In AML, trisomy 13 has been placed in the intermediate prognostic category although recent reports associate it with a more dismal outcome. The number of cases reported in the literature are relatively few, we reviewed our experience with trisomy 13 in hematologic malignancies to determine its significance and prognosis. Methods: We conducted a clinicopathological review of cases seen in our institution from January of 1990 to October of 2006. Our cytogenetic records were searched for patients, who had a hematological disorder whose non-stimulated bone marrow karyotype was found to have trisomy 13 as a sole abnormality. In men the absence of the Y chromosome was not regarded as a separate abnormality. Results: A total of 27 patients were identified. The median age was 76 years (range 25–87), 22/27 were male. The number of cases and diseases identified were 15 with AML, 5 with a myelodysplastic syndrome, 4 with an uncategorized myelodysplastic/myeloproliferative disorder, 2 with acute lymphoblastic leukemia and 1 with a chronic myeloproliferative disorder. Of the AML group 7 were M0 according to the FAB classification, 2 patients were identified to have M4 and another two M2. A single case each of M1 and M6 was also identified. In these 15 patients, 9 underwent induction chemotherapy, which consisted of intermediate dose Ara-C in 3 cases, anthracycline plus Ara-C in 5 patients, and daunorubicin, vincristine and prednisone in 1. Another 3 patients were given palliative treatment. For the rest of the subjects the type of treatment was unknown. A CR was obtained in 6 patients, 1 patient underwent a myeloablative stem cell transplant. Death has occurred in 24 patients, the median survival of the entire group was 5.4 months. In the patients with AML the median survival was 4.7 months, of the patients who achieved a CR the median survival was 9.5 months. Conclusions: We describe one of the largest series reported to date of trisomy 13 in hematologic malignancies and found that trisomy 13 is associated with male gender and an older age at presentation, as well as a poor prognosis. In AML its presence is associated with an FAB-M0 phenotype and its occurrence should be regarded as a high-risk feature. No significant financial relationships to disclose.

Abstract Background: Peripheral blood (PB) is sometimes used in place of bone marrow (BM) for cytogenetic studies during the evaluation of hematologic malignancies. We looked for clinical or laboratory features that predict success in obtaining analyzable metaphases during PB chromosome studies. Methods: The Mayo Clinic cytogenetics database was queried to identify adult cases (age > 18 years) with suspected or established hematologic neoplasm in whom PB cytogenetic studies were performed. Success defined as the acquisition of at least two metaphases, was correlated with clinical and laboratory information corresponding to the time of the PB cytogenetic study. Results: A total of 242 PB cytogenetic studies were performed: clinical diagnosis was a myeloid neoplasm in 169 patients (70%), lymphoid neoplasm in 50 (21%), and unexplained cytopenia or leukocytosis in 23 (9%). The 169 myeloid cases included 59 patients with either primary (n=39) or post-polycythemia vera/essential thrombocythemia (post-PV/ET MF) myelofibrosis (n=20), 42 with acute myeloid leukemia (AML), 15 with chronic myeloid leukemia, 9 with myelodysplastic syndrome (MDS), 8 with ET, 6 with PV, and 30 with other MPDs. The 50 lymphoid cases included 19 with chronic lymphocytic leukemia, 12 with lymphoma, 11 with acute lymphocytic leukemia (ALL), and 8 with plasma cell proliferative disorders. PB cytogenetic studies resulted in at least two analyzable metaphases (median 20, range 2–31) in 142 of the 242 study cases (59%); in univariate analysis, this was predicted by the specific clinical diagnosis (p<0.0001), presence and degree of circulating myeloid progenitor cells (p<0.0001), higher leukocyte count (p<0.001), lower platelet count (p=0.003), lower hemoglobin level (p=0.002), and presence of palpable splenomegaly (p=0.002). In multivariable analysis, only the presence of circulating myeloid progenitor cells sustained its significance and this was consistent with the high yield rates seen in PMF (80%), post-PV/ET MF (85%), AML (76%), and ALL (80%) as opposed to the low rates seen in ET (0%) and PV (2%). In 104 cases, BM cytogenetic studies were performed within one month of the PB cytogenetic studies; an abnormal BM cytogenetic finding was another independent predictor of a successful PB study (p=0.002). Conclusion: PB cytogenetic studies are most appropriate in diseases characterized by presence of circulating myeloid progenitors or blasts (e.g. PMF, AML, ALL); the yield otherwise is too small to be cost-effective. The current study also suggests a higher likelihood of a successful PB cytogenetic study in the presence of an abnormal bone marrow karyotype.

Abstract Background Although the clinical importance of del 17p13 in patients with chronic lymphocytic leukemia (CLL) is well recognized, the implications of when this defect is identified are less clearly defined. In particular, the distinction between the identification of del 17p13 at the time of diagnosis and secondary acquisition of del 17p13 during the course of the disease are poorly characterized. Methods We identified all patients with CLL cared for at the Mayo Clinic between 1/1/2000 and 12/31/2012 who underwent baseline fluorescence in-situ hybridization (FISH) testing prior to receiving treatment. The Results of repeat FISH testing were reviewed to identify cases with clinically ascertained clonal evolution. Results A total of 1757 patients with newly diagnosed CLL were seen at Mayo Clinic prior to receiving treatment. Among these, 1243 had FISH testing performed prior to treatment and within 36 months of diagnosis. The median time from diagnosis to initial FISH was 0.8 months (11.5 to 35.4 months). The Results of baseline FISH testing among these patients is as follows: 486 (39%) had del 13q14, 234 (19%) had trisomy 12, 115 (9%) had del 11q23, 59 (5%) had del 17p13, 15 (1%) had other (e.g., del6q) and 334 (37%) had no abnormalities detected. Among these patients, 344 (28%) underwent repeat FISH testing during the course of their disease. Repeat FISH testing was typically performed for clinical suspicion of karyotype evolution or prior to therapy selection in patients with a long time interval between first prognostic FISH and initiation of treatment. Among these 344 patients, 41 (12%) acquired new cytogenetic abnormalities on repeat FISH. Classification of these 344 patients by the Dohner classification at diagnosis and time of follow-up FISH is shown in Table 1. Among the 41 pts who acquired a new FISH detectable genetic abnormality, the newly acquired defect resulted in a change in Dohner FISH risk category for 39 patients including 15/41 (37%) who acquired a del 17p13. Baseline clinical and prognostic characteristics of patients who developed clonal evolution to those who did not are shown in Table 2. Patients with unmutated immunoglobulin heavy chain (IGHV) gene mutation status (p<0.0001) and CD49d (p=0.003) expression were more likely to experience clonal evolution. Among the 319 patients who did not have del 17p13 on baseline FISH, 15 (5%) acquired del 17p13 during the course of their disease. The overall survival from the date del 17p13 was identified is shown for those with del 17p13 at diagnosis (n=59) compared to those who acquired del 17p13 later in the course of the disease (n=15) in Figure 1A. Similarly, among 339 patients who did not have del 6q23 on baseline FISH, 9 (3%) acquired del 6q23 during the course of their disease. The overall survival from the date del 6q23 was identified is shown for those with del 6q23 at diagnosis (n=11) and those who acquired del 6q23 later in the course of the disease (n=9) in Figure 1B. Conclusion Acquired cytogenetic evolution is clinically ascertained by FISH during the course of the disease in approximately 12% of patients. The newly acquired defects in these patients result in a change in Dohner classification for in >90% of these patients including ∼37% who acquire del 17p13. The clinical implications of del 17p13 is influenced by the timing of ascertainment with markedly shorter survival for those who acquire del 17p13 during the course of the disease relative to those with this defect at diagnosis. Disclosures: Shanafelt: Genentech: Research Funding; Glaxo-Smith-Kline: Research Funding; Cephalon: Research Funding; Hospira: Research Funding; Celgene: Research Funding; Polyphenon E International: Research Funding.

Background: Our purpose was to evaluate the prognostic impact of pathologically confirmed esophageal adenosquamous carcinoma (ASC) and its association with HER2 status and clinicopathologic characteristics. Methods: Among 796 patients with esophageal or gastroesophageal junction adenocarcinoma who underwent curative resection, surgical pathology reports were reviewed, and suspected ASC was confirmed utilizing p63 and CK5/6 immunostaining. HER2 status was determined using immunohistochemistry and fluorescence in situ hybridization. Cox models were used to assess the impact of ASC on disease-specific survival and overall survival. Results: Overall, 2.0% (16/796) of patients had esophageal ASC, mostly demonstrating a close intermingling of squamous and adenocarcinoma cells within the same tumor. The percentage of squamous versus adenocarcinoma cells in the primary was generally recapitulated in nodal metastases, and intrapatient internodal heterogeneity was uncommon. Patients with esophageal ASC were statistically significantly more likely to be female (vs. male), have normal (vs. excess) body mass index, and harbor HER2-negative (vs. positive) tumors, as compared with patients with adenocarcinoma only. No ASC tumor was HER2-positive as compared with 16% of adenocarcinoma only tumors (P=0.018). Compared with patients with adenocarcinoma only, those with ASC demonstrated profoundly worse disease-specific survival (5-year event-free rate, 34% vs. 6%; multivariate hazard ratio, 2.87 [95% confidence interval, 1.59-4.76]; P=0.0010) and overall survival (P=0.0027) that was independent of known prognostic factors and HER2 status. Conclusion: ASC identifies a rare aggressive HER2-negative subgroup of esophageal/gastroesophageal junction adenocarcinoma.

2 Background: Testing for HER2 in EAC has become routine given its ability to predict benefit from HER2-targeted therapy. HER2 protein analysis by immunohistochemistry (IHC) is more rapid and generally less expensive than assessment of gene amplification by fluorescence in situ hybridization (FISH). However, the accuracy of IHC for predicting HER2 amplification has not been examined in a large EAC cohort. Methods: Surgical EAC specimens were examined from 675 patients who underwent curative resection at a single institution without preoperative therapy. Tumors were located in the esophagus (47%) or gastroesophageal junction (53%); most were node-positive (73%). Every tumor was evaluated by IHC in parallel with FISH in a blinded manner using FDA-approved assays. A consensus IHC score was determined by 2 pathologists using tumor-specific criteria (negative, 0 or 1+; equivocal, 2+; positive, 3+). Gene amplification by FISH was defined as a HER2/CEP17ratio ≥ 2. Results: HER2 amplification was detected in 89% of IHC 3+ cases, 13% of IHC 2+ cases, and 4% of IHC 0-1+ cases (Table). Accordingly, using FISH as the reference standard, the positive predictive value (PPV) of a positive IHC test (3+) was 89% (79/89 [95% CI 82%-95%]), and the negative predictive value of a negative IHC test (0-1+) was 96% (401/417 [94%-98%]). Importantly, the PPV of an equivocal IHC score (2+) for detecting HER2 amplification was 13% (22/169 [8%-18%]). Conclusions: In the largest study to date comparing HER2 testing methods in EAC, a negative IHC result (0 or 1+) nearly excludes the presence of gene amplification by FISH. Whereas a positive IHC result (3+) strongly predicts for the presence of amplification, an equivocal IHC result (2+) is a weak predictor. These findings in EAC support a HER2 testing algorithm where IHC is used for initial screening and FISH testing is restricted to cases with equivocal IHC results. [Table: see text]