Detection of HER2 status in breast cancer: comparison of current methods with MLPA and real-time RT-PCR.

Human epidermal growth factor receptor (HER) status is an important prognostic factor in breast cancer. There is no globally accepted method for determining its status, and which method is most precise is still a matter of debate. We here analyzed HER2 mRNA expression by quantitative reverse transcription-PCR (qRT-PCR) and HER2 DNA amplification using multiplex ligation-dependent probe amplification (MLPA). In parallel, we performed a routine evaluation of HER2 protein by immunohistochemistry (IHC). To assess the accuracy of the RT-PCR and MLPA techniques, a combination of IHC and fluorescence in situ hybridization (FISH) was used, substituting FISH when the results of IHC were ambiguous (2+) and for those IHC results that disagreed with MLPA and qRT-PCR, this approach being termed IHC-FISH. The IHC results for four samples were not compatible with the MLPA and qRT-PCR results; the MLPA and qRT-PCR results for these samples were confirmed by FISH. The correlations between IHC-FISH and qRT-PCR or MLPA were 0.945 and 0.973, respectively. The ASCO/CAP guideline IHC/FISH correlation with MLPA was (0.827) and with RT-PCR was (0.854). The correlations between the IHC results (0, 1+ as negative, and 3+ as positive) and qRT-PCR and MLPA techniques were 0.743 and 0.831, respectively. Given the shortcomings of IHC analysis and greater correlations between MLPA, qRT-PCR, and FISH methods than IHC analysis alone with each of these three methods, we propose that MLPA and real-time PCR are good alternatives to IHC. However a suitable cut-off point for qRT- PCR is a prerequisite for determining the exact status of HER2.

Angiogenesis markers in breast cancer--potentially useful tools for priority setting of anti-angiogenic agents.

BACKGROUND: Breast cancer is the most common malignancy among women in both developed and developing countries. The burden is increasing in low-income and middle-income countries (LMCs) and threatens the public health of such societies. Introduction of expensive monoclonal antibodies to cancer treatment regimens poses a real challenge in the health systems of LMCs. Despite controversy of cost-effectiveness of bevacizumab in breast cancer, some studies indicate gain of patients from this drug. The present study aimed to propose a priority setting model for administration of anti-angiogenic agents in breast cancer via assessment of tumor angiogenesis by the microvessel density (MVD) method and associations with clinicopathological characteristics (including simultaneous mutations of TP53 and HER-2 genes). MATERIALS AND METHODS: Age, axillary lymph nodes status, tumor size, stage and grade, estrogen and progesterone receptors status, HER-2/neu status (by immunohistochemistry and FISH test), TP53 mutation, Ki-67 (for proliferation assay) and CD34 (for angiogenesis assay) were assessed in 111 breast cancer patients. The molecular subtype of each tumor was also determined and correlations of simultaneous mutations of HER-2 and p53 genes with angiogenesis and other clinicopathological characteristics were evaluated. RESULTS: There were significant associations between simultaneous mutations of HER-2 and p53 genes and all other parameters except tumor size. The degree of angiogenesis in the ERBB2 subtype was greater than the others. Younger patients showed a higher angiogenesis rate rather those older than 50 years. CONCLUSIONS: Our results demonstrated that patients with simultaneous mutations of HER-2 and p53 genes, those with ERBB2 molecular subtype and also younger women (often triple negative) seem more eligible for obtaining anti-angiogenic agents. These results suggest a model for priority setting of patients with breast cancer for treatment with anti-angiogenic drugs in LMCs.