Immunohistochemistry and alternative FISH testing in breast cancer with HER2 equivocal amplification.

PURPOSE: While HER2 testing is well established in directing appropriate treatment for breast cancer, a small percentage of cases show equivocal results by immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH). Alternative probes may be used in equivocal cases. We present a single community-based institution's experience in further evaluating these cases. PATIENTS AND METHODS: Between 2014 and 2016, 4255 samples were submitted for HER2 amplification testing by alternative probes, TP53, RAI1, and RARA. Of the patients tested by FISH, 505/3908 (12.9%) also had IHC data. RESULTS: Most (73.9%) FISH equivocal cases remained equivocal after IHC testing. However, 50.5% of equivocal cases were classified as HER2 amplified by alternative probes. Most cases were positive by more than one probe: 78% of positive cases by RAI1 and 73.9% by TP53. There was a significant difference between IHC and FISH alternative testing (p < 0.0001) among the equivocal cases by conventional FISH testing, 44% of IHC negative cases became positive while 36% of the positive IHC cases became negative by alternative FISH testing. Available data showed that 41% of patients were treated with palbociclib and were positive by alternative FISH. CONCLUSION: The prevalence of double HER2 equivocal cases and the discrepancy between IHC and alternative FISH testing suggest that FISH alternative testing using both RAI1 and TP53 probes is necessary for conclusive classification. Because almost half of FISH equivocal cases converted to HER2 amplified upon alternative testing, clinical studies to determine the benefit of anti-HER2 therapy in these patients are urgently needed.

Preservation of quality of life in patients with human epidermal growth factor receptor 2-positive metastatic breast cancer treated with tucatinib or placebo when added to trastuzumab and capecitabine (HER2CLIMB trial).

AIMS: In HER2CLIMB, tucatinib significantly improved progression-free and overall survival in patients with human epidermal growth factor receptor 2-positive (HER2+) metastatic breast cancer. We evaluated the impact of tucatinib on health-related quality of life (HR-QoL) in HER2CLIMB. METHODS: Patients were randomised 2:1 to tucatinib or placebo combined with trastuzumab and capecitabine. Starting with protocol version 7, the EuroQol 5 Dimensions 5 Levels (EQ-5D-5L) questionnaire and EQ visual analogue scale (VAS) were administered at day 1 of cycle 1, every two cycles during cycles 3-9, every three cycles during cycle 12 and thereafter and at each patient's 30-day follow-up visit. RESULTS: Among 364 patients eligible for HR-QoL assessment, 331 (91%) completed ≥1 assessment. EQ-VAS scores were similar for both arms at baseline and maintained throughout treatment. EQ-5D-5L scores were similar between the treatment arms, stable throughout therapy and worsened after discontinuing treatment. Risk of meaningful deterioration (≥7 points) on EQ-VAS was reduced 19% in the tucatinib vs. placebo arm (hazard ratio [HR]: 0.81; 95% confidence interval [CI]: 0.55, 1.18); the median (95% CI) time to deterioration was not reached in the tucatinib arm and was 5.8 months (4.3, -) in the placebo arm. Among patients with brain metastases (n = 164), risk of meaningful deterioration on EQ-VAS was reduced 49% in the tucatinib arm (HR: 0.51; 95% CI: 0.28, 0.93); the median (95% CI) time to deterioration was not reached in the tucatinib arm and was 5.5 months (4.2, -) in the placebo arm. CONCLUSIONS: HR-QoL was preserved for patients with HER2+ metastatic breast cancer who were treated with tucatinib added to trastuzumab and capecitabine and maintained longer with tucatinib therapy than without it among those with brain metastases. CLINICAL TRIAL REGISTRATION: NCT02614794.

Reduced expression of TGF beta1RII in agnogenic myeloid metaplasia is not due to mutation or methylation.

Agnogenic myeloid metaplasia (AMM) is characterized by bone marrow fibrosis and enhanced proliferation of megakaryocytes and CD34+ cells. We have analyzed the factors that could lead to reduced expression of TGF beta1RII in CD34+ cells of AMM patients. Our results demonstrate absence of mutations in the coding region and the promoter of this gene and absence of CpG methylation of its promoter in AMM patients. Further studies on transcriptional regulation of TGF beta1RII involving its cis-regulatory elements, the interacting transcription factors and their association with HDAC will provide valuable information on the pathogenesis of AMM and are under current investigation.

Retinal vein thrombosis as the presenting symptom of essential thrombocythemia.

Visual loss resulting from retinal vascular disorders can be the presenting sign of serious systemic disease. Associations between retinal vein thrombosis and other systemic disorders have been well documented, but a comprehensive literature search failed to reveal any report of essential thrombocythemia as a cause of central retinal vein thrombosis. We describe the first young female patient with symptomatic visual loss due to central retinal vein thrombosis as her presenting symptom of essential thrombocythemia.