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This Australian human epidermal growth factor receptor 2 (HER2) testing program aimed to analyse >800 cases tested in a coordinated setting to further evaluate the criteria to establish HER2 status in advanced gastric and gastro-oesophageal junction (GOJ) cancer. Heterogeneity, and minimum number of biopsy fragments for reliable HER2 assessment were also examined in a subset of samples. Five laboratories tested 891 samples referred to determine HER2 status for potential anti-HER2 treatment. Cancer site, specimen type (endoscopic biopsy/resection/metastases), immunohistochemistry (IHC) score, HER2 gene and CEP17 copy number (CN) and HER2:CEP17 ratios were recorded. Samples were derived from stomach (53.1%), GOJ (28.2%) or metastases (18.5%). IHC for HER2 and dual probe HER2:CEP17 in situ hybridisation (ISH) were performed in parallel. A stringent definition (SD) of HER2 positivity was used (IHC2+/3+ plus CN>6 and ratio>2) and compared with other published criteria. HER2 positive rate was 13.9% (114/820) by SD, and 12.9-16.0% using other definitions. There was higher concordance between IHC and HER2 CN by ISH than with ratio. The HER2 positive rate was significantly higher in GOJ samples than others (p = 0.03) and in endoscopic biopsies than resections (p = 0.047). In a subset of 98 positive cases, 39 (39.8%) showed heterogeneity, and in 282 endoscopic biopsies positivity rate plateaued at five tumour fragments, suggesting this is the minimum number of biopsies that should be examined., (Copyright © 2017 Royal College of Pathologists of Australasia. All rights reserved.)

Appropriate and accurate determination of HER2 status in women with breast cancer is critical for stratifying anti-HER2 therapies, and for access to subsidised treatment in the Australian setting. We conducted a regulated, nationwide program providing HER2 in situ hybridisation (ISH) testing for patients with newly diagnosed breast cancer. Cases with equivocal or non-diagnostic ISH test results at the local laboratory were sent to a high volume central testing laboratory for analysis using fluorescence ISH (FISH). We tested 78,408 early breast cancers and 3469 metastatic cancers using ISH. Of these, 12,405 early breast cancers (15.8%) and 798 metastatic cancers (23.0%) were HER2 positive. During the testing period, the proportion of core biopsy samples increased, the number of repeat tests remained stable and testing turnaround time declined. Discordant 3+ IHC, ISH negative results dropped from 20% to 13% in early breast cancers and from 35% to 8% among metastatic breast cancers. Following central laboratory FISH testing only 87 samples remained non-diagnostic (1.9% of FISH-tested samples, 0.1% of the whole cohort), most being decalcified specimens. This is a successful story of a cohesive service determining HER2 status in women with breast cancer in a 'real-world' setting., (Copyright © 2016 Royal College of Pathologists of Australasia. Published by Elsevier B.V. All rights reserved.)

Purpose: To determine the clinical utility of intrinsic molecular phenotype after breast-conserving therapy (BCT) with lumpectomy and whole-breast irradiation with or without a cavity boost., Patients and Methods: Four hundred ninety-eight patients with invasive breast cancer were enrolled into a randomized trial of BCT with or without a tumor bed radiation boost. Tumors were classified by intrinsic molecular phenotype as luminal A or B, HER-2, basal-like, or unclassified using a five-biomarker panel: estrogen receptor, progesterone receptor, HER-2, CK5/6, and epidermal growth factor receptor. Kaplan-Meier and Cox proportional hazards methodology were used to ascertain relationships to ipsilateral breast tumor recurrence (IBTR), locoregional recurrence (LRR), distant disease-free survival (DDFS), and death from breast cancer., Results: Median follow-up was 84 months. Three hundred ninety-four patients were classified as luminal A, 23 were luminal B, 52 were basal, 13 were HER-2, and 16 were unclassified. There were 24 IBTR (4.8%), 35 LRR (7%), 47 distant metastases (9.4%), and 37 breast cancer deaths (7.4%). The overall 5-year disease-free rates for the whole cohort were: IBTR 97.4%, LRR 95.6%, DDFS 92.9%, and breast cancer-specific death 96.3%. A significant difference was observed for survival between subtypes for LRR (P = .012), DDFS (P = .0035), and breast cancer-specific death (P = .0482), but not for IBTR (P = .346)., Conclusion: The 5-year and 10-year survival rates varied according to molecular subtype. Although this approach provides additional information to predict time to IBTR, LRR, DDFS, and death from breast cancer, its predictive power is less than that of traditional pathologic indices. This information may be useful in discussing outcomes and planning management with patients after BCT.

Background & Aims: Current methods of preoperative staging and predicting outcome following pancreatectomy for pancreatic cancer (PC) are inadequate. We evaluated the utility of multiple biomarkers from distinct biologic pathways as potential predictive markers of response to pancreatectomy and patient survival., Methods: We assessed the relationship of candidate biomarkers known, or suspected, to be aberrantly expressed in PC, with disease-specific survival and response to therapy in a cohort of 601 patients., Results: Of the 17 candidate biomarkers examined, only elevated expression of S100A2 was an independent predictor of survival in both the training (n = 162) and validation sets (n = 439; hazard ratio [HR], 2.19; 95% confidence interval [CI]: 1.48-3.25; P < .0001) when assessed in a multivariate model with clinical variables. Patients with high S100A2 expressing tumors had no survival benefit with pancreatectomy compared with those with locally advanced disease, whereas those without high S100A2 expression had a survival advantage of 10.6 months (19.4 vs 8.8 months, respectively) and a HR of 3.23 (95% CI: 2.39-4.33; P < .0001). Of significance, patients with S100A2-negative tumors had a significant survival benefit from pancreatectomy even in the presence of involved surgical margins (median, 15.7 months; P = .0007) or lymph node metastases (median, 17.4 months; P = .0002)., Conclusions: S100A2 expression is a good predictor of response to pancreatectomy for PC and suggests that high S100A2 expression may be a marker of a metastatic phenotype. Prospective measurement of S100A2 expression in diagnostic biopsy samples has potential clinical utility as a predictive marker of response to pancreatectomy and other therapies that target locoregional disease.

Purpose: Identification of biologically and clinically distinct breast cancer subtypes could improve prognostic assessment of primary tumors. The characteristics of "molecular" breast cancer subtypes suggest that routinely assessed histopathologic features in combination with limited biomarkers may provide an informative classification for routine use., Experimental Design: Hierarchical cluster analysis based on components of histopathologic grade (tubule formation, nuclear pleomorphism, and mitotic score), expression of ER, cytokeratin 5/6, and HER2 amplification identified four breast cancer subgroups in a cohort of 270 cases. Cluster subgroup membership was compared with observed and Adjuvant! Online predicted 10-year survival. Survival characteristics were confirmed in an independent cohort of 300 cases assigned to cluster subgroups using a decision tree model., Results: Four distinct breast cancer cluster subgroups (A-D) were identified that were analogous to molecular tumor types and showed a significant association with survival in both the original and validation cohorts (P < 0.001). There was a striking difference between survival for patients in cluster subgroups A and B with ER(+) breast cancer (P < 0.001). Outcome for all tumor types was well estimated by Adjuvant! Online, with the exception of cluster B ER(+) cancers where Adjuvant! Online was too optimistic., Conclusions: Breast cancer subclassification based on readily accessible pathologic features could improve prognostic assessment of ER(+) breast cancer.

The conventional method of scoring Her2/neu immunostaining is recognized to result in a high false-positive rate among 2+ cases when compared with results obtained with fluorescence in situ hybridization (FISH); however, costs and convenience dictates that immunohistochemistry remains the screening test for Her2/neu status in patients with breast cancer. We describe refined criteria for scoring of Her2/neu on the basis of anatomic localization rather than the subjective assessment of intensity. The presence of a circumferential tram track pattern that results from the staining of apposing cell membranes in >25% of the tumor cells was necessary for a 3+ score (Her2/neu overexpressed) and the presence of the tram track pattern in <25% was scored 2+ (equivocal); granular and fragmented membrane staining was scored 1+ (negative). The tram track pattern of Her2/neu overexpression showed 100% concordance with gene amplification. FISH and CISH testing in selected cases from the other categories validated the revised scoring method. These criteria reduced the numbers of equivocal staining cases that required FISH testing.

Purpose: Prognostic indicators in pancreatic cancer (PC) are poorly defined and difficult to quantify preoperatively, hence they may lead to inappropriate patient selection for treatment. We examined the protein expression of key cell-cycle regulatory and cell-signaling molecules that occur at high frequency in PC and assessed their relationship to clinicopathologic parameters, response to operative resection, and outcome., Patients and Methods: We identified 348 patients with pancreatic ductal adenocarcinoma and assessed the influence of reported clinicopathologic prognostic factors and the expression of the cell-cycle regulatory genes p21(WAF1/CIP1) (CDKN1A), cyclin D1 (CCND1), p53, and p16(INK4A) (CDKN2) and the cell-signaling molecule DPC4/Smad4 (MADH4) using immunohistochemistry in a subgroup of 129 patients., Results: Independent prognostic factors in resected patients were tumor size greater than 45 mm (P =.0015), involvement of surgical margins (P <.0001), and perineural invasion (P =.014). Loss of DPC4/Smad4 expression cosegregated with resectability (P <.0001) and was associated with improved survival after resection (P <.0001), whereas resection did not improve survival in patients whose tumor expressed DPC4/Smad4 (P =.5). Aberrant expression of p21(WAF1/CIP1), cyclin D1, p53, or p16(INK4A) was not associated with a difference in survival., Conclusion: Tumor size (> 45 mm), resection margin involvement, and perineural invasion were independent prognostic factors. Preoperative assessment of DPC4/Smad4 expression has potential as a prognostic indicator in patients with PC since resection did not benefit those patients whose cancers expressed DPC4/Smad4 and accurate assessment of DPC4/Smad4 expression, unlike tumor size, margin status, and perineural invasion, does not require resection.