Biological Subtypes Of Breast Cancer Research Articles

Evaluation of Ultrasound and Intraoperative Histological Methods in the Diagnosis of Sentinel Lymph Node Metastases in Various Biological Subtypes of Breast Cancer

Evaluation of Ultrasound and Intraoperative Histological Methods in the Diagnosis of Sentinel Lymph Node Metastases in Various Biological Subtypes of Breast Cancer

Radiomics in the Radiation Diagnosis of Biological Subtypes of Breast Cancer (Literature Review)

Radiomics in the Radiation Diagnosis of Biological Subtypes of Breast Cancer (Literature Review)

The Role of Salivary Vascular Endothelial Growth Factor A, Cytokines, and Amino Acids in Immunomodulation and Angiogenesis in Breast Cancer.

In this work, we focused on the analysis of VEGF content in saliva and its relationship with pro-inflammatory cytokines and amino acids involved in immunomodulation and angiogenesis in breast cancer. The study included 230 breast cancer patients, 92 patients with benign breast disease, and 59 healthy controls. Before treatment, saliva samples were obtained from all participants, and the content of VEGF and cytokines in saliva was determined by an enzyme-linked immunosorbent assay, as well as the content of amino acids by high-performance liquid chromatography. It was found that VEGF was positively correlated with the level of pro-inflammatory cytokines IL-1β (r = 0.6367), IL-6 (r = 0.3813), IL-8 (r = 0.4370), and IL-18 (r = 0.4184). Weak correlations were shown for MCP-1 (r = 0.2663) and TNF-α (r = 0.2817). For the first time, we demonstrated changes in the concentration of VEGF and related cytokines in saliva in different molecular biological subtypes of breast cancer depending on the stage of the disease, differentiation, proliferation, and metastasis to the lymph nodes. A correlation was established between the expression of VEGF and the content of aspartic acid (r = -0.3050), citrulline (r = -0.2914), and tryptophan (r = 0.3382) in saliva. It has been suggested that aspartic acid and citrulline influence the expression of VEGF via the synthesis of the signaling molecule NO, and then tryptophan ensures tolerance of the immune system to tumor cells.

Free Salivary Amino Acid Profile in Breast Cancer: Clinicopathological and Molecular Biological Features.

The study of salivary amino acid profiles has attracted the attention of researchers, since amino acids are actively involved in most metabolic processes, including breast cancer. In this study, we analyzed the amino acid profile of saliva in a sample including all molecular biological subtypes of breast cancer to obtain a more complete picture and evaluate the potential utility of individual amino acids or their combinations for diagnostic purposes. This study included 116 patients with breast cancer, 24 patients with benign breast disease, and 25 healthy controls. From all patients, strictly before the start of treatment, saliva samples were collected, and the quantitative content of 26 amino acids was determined. Statistically significant differences between the three groups are shown in the content of Asp, Gly, Leu + Ile, Orn, Phe, Pro, Thr, and Tyr. To differentiate the three groups from each other, a decision tree was built. To construct it, we selected those amino acids for which the change in concentrations in the subgroups was multidirectional (GABA, Hyl, Arg, His, Pro, and Car). For the first time, it is shown that the amino acid profile of saliva depends on the molecular biological subtype of breast cancer. The most significant differences are shown for the luminal B HER2-positive and TNBC subgroups. In our opinion, it is critically important to consider the molecular biological subtype of breast cancer when searching for potential diagnostic markers.

Mechanical properties of breast cancer cells of different molecular biological subtypes in reaction with antibodies against CD109 antigen

The cytoskeleton is a participant in key cell events in oncogenesis and the reaction of cancer cells to therapeutic factors. The state and structure of the actin cytoskeleton contributes significantly to the mechanical behavior of cancer cells, forming the main features of their mechanical phenotype.In the work, using atomic-force microscopy and fluorescent microscopy, we studied the changes in the structure of the actin cytoskeleton and parameters of the mechanical properties of breast cancer cells of different molecular biological subtypes (hormone-sensitive, line ZR-75, and triple-negative, BT-20 line, subtypes) when cells interact with the CD109 antigen, a TGF-β signaling pathway inhibitor. The use of antibodies for immobilizing the CD109 antigen has been shown to cause significant changes in the spatial organization of the actin cytoskeleton, stiffness and adhesive properties of the cell surface of both cell lines. Because of differences in the structure of the actin cytoskeleton, changes in the mechanical properties of the cells of different molecular biological breast cancer subtypes and the implementation of the TGF-β signaling pathway in these cells when binding to antibodies against the CD109 antigen occur in different ways. The obtained data open new perspectives for the development and evaluation of the effectiveness of anticancer drugs.

Recent advances in the treatment of triple-negative breast cancer

Triple-negative is the rarest breast cancer biological subtype of breast cancer, but has the most aggressive course. The resuls of chemotherapy, especially in advanced disease, are unsatisfactory. Numerous clinical trials have been conducted, that resulted in registrations of new drugs decreasing the risk of recurrence and improving the outcome of patients with metastatic disease. The article summarizes the data on modern therapies registered in recent years. The role of pembrolizumab in perioperative treatment in the early stage was indicated, as well as the importance of olaparib in BRCA mutation carriers. Additionally, in patients with metastatic the indication for immunotherapy (pembrolizumab and atezolizumab), sacituzumab govitecan and PARP inhibitors (olaparib and talazoparib) in BRCA mutation carriers were highlighted.

Concordance Between Core Needle Biopsy and Surgical Specimens in Determining Molecular Biological Subtypes of Breast Cancer by Immunohistochemistry

Background: Breast carcinoma is the most common malignancy among women around the world. Core needle biopsy provides samples that are adequate in size thus allowing a histological diagnosis of breast carcinomas. CNB specimens can also be used for the immunohistochemical (IHC) assays of hormone receptors. Aims: To evaluate the concordance of ER, PR, HER2 Neu and Ki-67 in core needle biopsy and surgical specimens obtained by Modified radical mastectomy (MRM). Methods: A cross-sectional observational study was conducted in the Department of Pathology in association with the Department of Surgery at Murshidabad Medical College and Hospital for a duration of one and a half years. Patients undergoing Core needle biopsy of the breast who have been diagnosed with breast carcinoma on the basis of histopathology report and subsequently planned for MRM who have given consent for the study were included in this study. The samples were classified according to the immunohistochemical staining into four molecular subtypes: Luminal A, Luminal B, HER 2 Neu enriched, and triple-negative subtype depending on the expression of ER, PR, HER 2 Neu, and Ki-67. Result: The most common molecular subtype of breast carcinoma in both CNB and MRM specimens was the Triple-negative subtype. Conclusion: CNB has been found to be a reliable diagnostic tool that can help in determining Histopathological biomarkers for ER, PR positive, and HER2 Neu positive or negative tumors and it has also been found that retesting these markers again on the surgical specimens may not be necessary. Keywords: Core needle biopsy, Breast carcinoma, Molecular subtyping, Immunohistochemistry

High prevalance of triple negative markers in breast cancer patients in North Maharashtra

Breast cancer is the most prevalent cancer among women worldwide. The Bloom Richardson grading has been applied to most breast cancers. There are different biologic subtypes of breast cancer according to immunohistochemistry (IHC). Clinically, these subtypes are characterized on the basis of expression of estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2). Among them, Triple Negative Breast Cancer (TNBC) which lacks expression of the ER, PR, and HER-2-neu, is most aggressive form. TNBC cases have worse prognosis, require aggressive chemotherapy and are difficult to manage. The advent of neoadjuvant chemotherapy has highlighted the importance of IHC, Breast Ca and TNBC. The aim and objective of this study is to find prevalence of TNBC in Breast Cancer patients in North Maharashtra. This is a 3- Year ambiceptive analysis done to study the incidence of TNBC among Breast Cancer cases. Out of 58 Breast Cancer cases diagnosed in our institute, 30 cases in which IHC was done were included in this study. Postmortem breast cancer cases, core needle biopsies and mastectomies in which IHC was not done were excluded. Among 30 cases studied, 53.33% cases were TNBC, 23.33% cases were ER and PR positive, 10% cases were only HER-2-neu positive, 6.66% cases were only ER positive, 3.33% cases were only PR positive, and 3.33% cases were all three ER, PR and HER-2 neu positive. To conclude, India has considerably higher prevalence of TNBC, as compared to the Western countries. This finding has significant clinical relevance as it may have contributed to poor outcomes in patients with breast cancer in India. With advent of neoadjuvant chemotherapy, use of Modified Bloom- Richardson Grading & IHC is of crucial importance. To understand the determinants of TNBC in India additional research is needed for diagnosis and treatment follow-up.

Updated CAP guidelines for determining molecular biological subtypes of breast cancer

Updated 2023 guidelines from the College of American Pathologists (CAP) on immunohistochemical detection of human epidermal growth factor receptor type 2 (HER2), receptors of estrogen (ER) and progesterone (PgR), and the cell proliferation marker Ki-67 in breast cancer are presented. Attention is drawn to the emergence of two new terms «ER Low Positive» and «HER2 Low» to characterize tumors with low expression of estrogen receptors and HER2.

Radionuclide imaging of breast cancer: experience of FSBI “N.N. Petrov National Medical Research Centre of Oncology” of the Ministry of Healthcare of Russian Federation

Abstract. Breast cancer is one of the most common malignant neoplasms among women nowadays. Timely diagnosis is the basis for effective and successful treatment of this disease. The existing classical methods of X-ray examination (MG, ultrasound, MRI) play a major role in the detection of breast cancer, but in some cases, the diagnosis of breast cancer can be difficult. Therefore, diagnostic performance of scintimammography with specialized gamma camera called molecular breast imaging (MBI) is now of particular clinical interest.Materials and methods. 312 patients with a preliminary clinical diagnosis of breast cancer were examined in the department of radionuclide diagnostics of N.N. Petrov Research Center of Oncology. They underwent scintimammography (MBI) with a specialized gamma camera manufactured by GE (Discovery 750b). Images of both breasts were obtained 15 min after intravenous injection of 500 MBq activity of 99mTc-MIBI. The foci of moderate and intensive radiopharmaceutical accumulation in breast were considered as a sign of a tumor. The diagnostic performance of MBI and the sensitivity in detection of various biological subtypes of cancer were calculated by comparing with the results of morphological and immunohistochemically studies.Results. The sensitivity, specificity and accuracy of the MBI in the diagnostics of breast cancer were 88, 75 and 87%, respectively. Sensitivity of this method in detection of different biological subtypes ranged from 89% to 95% with lowest performance found in luminal A subtype.Conclusion. Scintimammography (MBI) is an informative way of breast cancer diagnostics. The revealed differences in the sensitivity of the method in patients with different biological subtypes of breast cancer confirm the need for further study of this topic.

Association of matrix metalloproteinase gene polymorphisms with different biological subtypes of breast cancer

Aim. To investigate the associations of matrix metalloproteinase (MMP) MMP3 (rs679620), MMP8 (rs1940475), and MMP9 (rs17576 and rs3787268) gene polymorphisms with different biological subtypes of breast cancer (BC).
 Materials and methods. The study sample consisted of 285 patients with BC of various biological subtypes (luminal A and B [n=153], triple negative [n=108], and HER2 positive [HER2+, n=24]) and 746 females in the control group. Genotyping of four polymorphic sites of MMP3 (rs679620), MMP8 (rs1940475), and MMP9 (rs17576 and rs3787268) genes was performed in the study groups.
 Results. The role of MMP gene polymorphisms in the BC development of various biological subtypes differs. The c.836 AG MMP9 polymorphism (rs17576, the odds ratio is 0.670.71 for the G allele) has a protective effect on the development of luminal A- and B-subtypes of BC; susceptibility to triple-negative BC is associated with the polymorphic site c.1331-163 GA MMP9 (rs3787268, OR 4.51 for genotype AA), and two polymorphisms of the MMP3 (c.133 TC, rs679620, OR 0.460.49 for T allele) and MMP8 (c.259 TC, rs1940475, OR 0.370.48 for T allele) genes are associated with HER2+ BC development. According to the in silico data, the above polymorphisms have pronounced functional effects in organs and tissues that are pathogenetically significant for the disease, including the target organ, the breast.
 Conclusion. The c.836 AG MMP9 (rs17576) polymorphism is associated with luminal A- and B-subtype of BC; c.1331-163 GA MMP9 (rs3787268) is associated with triple negative BC, and c.133 TC MMP3 (rs679620) and c.259 TC MMP8 (rs1940475) are involved in HER2+ BC development.

Biological subtypes of breast cancer and their impact on recurrence and survival rates: Alexandria surgical oncology unit experience

Biological subtypes of breast cancer and their impact on recurrence and survival rates: Alexandria surgical oncology unit experience

First, do no harm: risk of secondary cancer after breast cancer treatment.

Breast cancer is the most common malignancy in women worldwide, and the majority of women will survive a diagnosis of early stage disease. As our understanding of the biological subtypes of breast cancer has expanded, treatments for breast cancer have become increasingly tailored, balancing treatment sensitivity, benefits, and individual patient preferences. For this common cancer with substantial long-term survival, health-care providers must weigh therapeutic benefits against short-term and long-term risks.

«Salivaomics» of Different Molecular Biological Subtypes of Breast Cancer

The aim of the study was to determine the metabolic characteristics of saliva depending on the molecular biological subtype of breast cancer, as well as depending on the expression levels of HER2, estrogen receptors (ER), and progesterone receptors (PR). The study included 487 patients with morphologically verified breast cancer and 298 volunteers without breast pathologies. Saliva samples were obtained from all patients strictly before the start of treatment and the values of 42 biochemical indicators were determined. It has been established that the saliva of healthy volunteers and patients with various molecular biological subtypes of breast cancer differs in 12 biochemical indicators: concentrations of protein, urea, nitric oxide, malondialdehyde, total amino acid content, and activity of lactate dehydrogenase, alkaline phosphatase, gamma-glutamyltransferase, catalase, amylase, superoxide dismutase, and peroxidases. The saliva composition of patients with basal-like breast cancer differs from other subtypes in terms of the maximum number of indicators. Changes in biochemical indicators indicated an increase in the processes of lipid peroxidation and endogenous intoxication and a weakening of antioxidant protection, which correlates with the severity of the disease and the least favorable prognosis for this subtype of breast cancer. An analysis was made of the individual contribution of the expression level of HER2, estrogen, and progesterone receptors to changes in the biochemical composition of saliva. The HER2 (−)/HER2 (+) group, which should be considered as a single group, as well as ER-positive breast cancer, differ statistically significantly from the control group. For ER/PR-positive breast cancer, a more favorable ratio of saliva biochemical indicators was also noted compared to ER/PR-negative breast cancer.

Abstract P3-02-04: Prediction of breast cancer response to neoadjuvant chemotherapy in different biological breast cancer subtypes using diffuse optical tomography

Abstract Background: Optical-based imaging modalities play an important role in assessing breast tissue composition by measuring optical property contrast from endogenous chromophores. The advantages of optical techniques are the use of non-ionizing radiation, ease of use, and relatively low cost. The primary objective of this study is to examine changes in optically derived parameters (i.e., deoxy-hemoglobin concentration, ctHHb) from different breast cancer subtypes under neoadjuvant chemotherapy (NAC), and correlate with tumor pathologic complete response (pCR). Methods: This retrospective study evaluated 89 tumors in total divided into three distinct subtypes: HR+/HER2- (n=34), HER2+ (n=27), and TNBC (n=28). All patients were imaged at baseline, before starting NAC (TP0), and two weeks after receiving one cycle of taxane-based chemotherapy (TP1). HER2+ breast cancer patients also received HER2-target therapy. pCR was defined as complete absence of invasive carcinoma in the breast and lymph node(s) (ypT0/is ypN0 Mx) at the time of surgery. Whole breast volume was imaged by a diffuse optical tomography breast imaging system (DOTBIS) using low-intensity near-infrared light. ctHHb tumor volume concentration was normalized by the non-affected health tissue ctHHb mean value (ctHHbN). For each molecular subgroup, we conducted an independent-samples t-test to determine if there was a difference in ctHHbN levels at TP1 compared to TP0 between patients with a pCR and non-pCR. Significance was assumed at a confidence interval of 95% (α = 0.05). Results: In total, 69 patients were imaged with DOTIBS at both time points, TP0 and TP1. HR+/HER2-, TNBC and HER2+ accounted for 32% (n=23), 37% (n=22) and 30% (n=22), respectively. The ratio between ctHHbN levels measured at TP1 and TP0 was statistically significantly lower in the pCR group than non-pCR for the HER2+ and HR+/HER2- molecular subgroups, Table 1. Conclusion: Aligned to the current practices in breast cancer management based on the characterization of breast cancer subtypes, our work evaluated changes in DOTBIS optically derived features and pCR status for different subtypes. We observed that ctHHbN levels change after two weeks of NAC and these changes are modifiable according to pCR status and are dependent on immunophenotype. Table 1.Ratio between ctHHbN levels measured at TP1 and TP0 between pCR and non-pCR according to different molecular subtypes.Molecular SubtypepCR (mean ± SD )non-pCR (mean ± SD )p-valueHR+/HER2- (n=23)0.77 ± 0.22 (n=6)1.14 ± 0.24 (n=17).01HER2+ (n=24)0.74 ± 0.30 (n=15)1.54 ± 0.98 (n=9).04TNBC (n=22)0.96 ± 0.38 (n=4)1.29 ± 0.37 (n=18).18Bold values indicate statistical significance at p<.05 level. Citation Format: Mirella L Altoe, Kevin M Kalinsky, Hua Guo, Hanina Hibshoosh, Mariella Tejada, Katherine D Crew, Melissa K Accordino, Meghna S Trivedi, Alessandro Marone, Hyun K Kim, Andreas H Hielscher, Dawn L Hershman. Prediction of breast cancer response to neoadjuvant chemotherapy in different biological breast cancer subtypes using diffuse optical tomography [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P3-02-04.

Intracranial Response Rate in Patients with Breast Cancer Brain Metastases after Systemic Therapy.

Simple SummaryFor many years, patients with breast cancer and brain metastases were excluded from participation in clinical trials. It was believed that anticancer drugs could not cross the blood–brain barrier. However, recent evidence strongly suggests that some drugs can act against brain metastases, with the greatest intracranial response rate reported in the case of capecitabine, neratinib plus capecitabine, trastuzumab deruxtecan and tucatinib plus trastuzumab and capecitabine. In this article, we discuss the achievements in systemic therapy of breast cancer patients with brain metastases. We stress on the newest clinical trial results which indicate tremendous progress in HER2-positive breast cancer. On the other hand, in patients with triple-negative breast cancer or hormone-receptor-positive brain metastases, much fewer compounds were discovered. Based on the presented results, patients with active brain metastases should be routinely included in clinical trials with novel agents.Brain metastases are detected in 5% of patients with breast cancer at diagnosis. The rate of brain metastases is higher in HER2-positive and triple-negative breast cancer patients (TNBC). In patients with metastatic breast cancer, the risk of brain metastases is much higher, with up to 50% of the patients having two aggressive biological breast cancer subtypes. The prognosis for such patients is poor. Until recently, little was known about the response to systemic therapy in brain metastases. The number of trials dedicated to breast cancer with brain metastases was scarce. Our review summarizes the current knowledge on this topic including very significant results of clinical trials which have been presented very recently. We focus on the intracranial response rate of modern drugs, including new antibody–drug conjugates, HER2- targeted tyrosine kinase inhibitors and other targeted therapies. We highlight the most effective and promising drugs. On the other hand, we also suggest that further efforts are needed to improve the prognosis, especially patients with TNBC and brain metastases. The information contained in this article can help oncologists make treatment-related decisions.

Иммуногистохимическая характеристика сторожевых лимфатических узлов при разных молекулярно-биологических подтипах рака молочной железы

Introduction. Breast cancer in women is a very common malignant tumor. The prognosis of the development and management of the disease depend on the clinical stage and biological subtype of the tumor. The aim of the research was to study immunohistochemical characteristics of sentinel lymph nodes in various molecular and biological subtypes of breast cancer. Materials and methods. We studied 44 lymph nodes of females with a diagnosed breast cancer using histological and immunohistochemical methods. Regional axillary lymph nodes without signs of metastatic lesions were taken into the investigation. Hematoxylin and eosin staining was performed; monoclonal antibodies to S100 protein and cluster of lymphocyte differentiation 4 and 8 were used. We used light microscopy to assess the results. Results. We determined molecular and biological subtypes of breast cancer. In 45.5% of cases (n=20) women were diagnosed with luminal cancer (Lum); in 25% of cases (n=11), with Her2+ variant; and in 29.5% of cases (n=13), with Tr– cancer (triple-negative). A more pronounced expression of S100-positive cells was observed in the paracortical zone of lymph nodes in triple-negative compared with the luminal one. We revealed uneven distribution of СD8+ lymphocytes in various subtypes of breast cancer, with an increase in their area in the following sequence: Lum (18.6%), Her2+ (19.8%), and Tr– (20.1%). The lowest number of СD4+ lymphocytes was found in the luminal breast cancer. The largest number of CD4+ cells was observed in the Her2+ subtype. Conclusion. The research demonstrated no reliable differences in the reaction of various sub-populations of T-lymphocytes in early-stage breast cancer. At the same time, we revealed a reliable increase in the number of intrafollicular S100+ cells that indicates dendrite cells activation in Tr– cancer. Keywords: breast cancer, immunohistochemistry, regional lymph node, cellular immunity, lymphocytes

Diagnostic potentials of modern radiothermometry in oncomammological practice

Background: Radiothermometry (RTM) is a breast examination method that permits, besides visualization of the pathological foci, to evaluate the quality of metabolism, which is important for the determination of the biological subtypes of breast cancer (BC) and the possibility of the evaluation of the degree of tumor aggressiveness before immunohistochemical analysis.
 Aim: To study the potentials of modern RTM in the differential diagnosis of benign and malignant breast pathologies and in different biological subtypes of BC.
 Materials and methods: Overall, 118 patients with different breast pathologies were examined using РТМ 01 РЭС computerized diagnostic complex. Measurements were performed in nine points: directly on the breast ― for the visualization of tumor, in two control points (in the region of the epigastrium and sternal xiphoid process), and in one point in the axillary zone on both sides ― for the identification of probable metastases. The examination time was 1520 min for each woman. RTM results were compared with histological, ultrasound, mammographic, and clinical data.
 Results: The sensitivity and accuracy of RMT in the differential diagnosis of breast pathology were 96.9% and 74.5%, respectively. The specificity of RTM in the differentiation of aggressive and non-aggressive BC subtypes appeared to be low at 6.6%. In the evaluation of the temperature difference between the pathological and normal tissues, a tendency to a non-increase in the temperature above the tumor in comparison with the unaffected tissue was noted; however, no significant differences between the mean values for the healthy and affected breasts were obtained. No correlations were found between the proliferative index of BC and frequency of thermoasymmetry or extent of its evidence (r 0.3).
 Conclusion: RTM demonstrated effectiveness in the differential diagnosis of benign and malignant alterations of the breast; thus, it is not a method of choice in the evaluation of the spread and biological subtype of BC.

Blood levels of growth and progression factors in patients with locally advanced breast cancer during neoadjuvant chemotherapy

Purpose of the study. An analysis of blood levels of TGF-β, TGFR2, TNF-α, TNF-αR1, TNF-αR2, CD44 and MMP9 in patients with various biological subtypes of breast cancer receiving neoadjuvant chemotherapy.Materials and methods. This article presents an analysis of levels of growth and progression factors (TGF-β, TGFR2, TNF-α, TNF-αR1, TNF-αR2, CD44 and MMP9) in the blood of 162 patients with various biological subtypes of locally advanced breast cancer receiving 8 cycles of neoadjuvant chemotherapy.Results. Levels of TGF-β, TGFR2, TNF, TNF-α, TNFR1, TNFR2, CD44, MMP9 in patients with all BC subtypes were high before the treatment. After chemotherapy cycles, the values decreased statistically significantly in all BC subtypes: CD44 decreased by 25.2 %, 30 % and 54.7 % in luminal A, luminal B and TNBC, respectively; TNFα– by 26.2 %, 48.3 % and 50.8 %, respectively; TNFα-R1 – by 52.1 %, 39.2 % and 50.3 % respectively; TNFα-R2 – by 31.7 %, 32.8 % and 41.9 % respectively; MMP9 – 35.3 %, 32.6 % and 43.3 % respectively.Conclusions. We identified a combination of growth and progression factors which determines the chemotherapy sensitivity and resistance in all subtypes of breast cancer; so, a decline in the levels of TGF-β, TNFα, MMP9 and CD44 after neoadjuvant chemotherapy predicts further remission for at least 3 years. On the contrary, stabilization or an increase of these indicators leads to the early tumor progression.

Cerebellar preference of luminal A and B type and basal ganglial preference of HER2-positive type breast cancer-derived brain metastases.

The purpose of the current study was to investigate the hypothesis that the spatial distribution of brain metastases could be affected by the biological subtypes of breast cancer. CT (n=1) or MRI (n=66) images of 67 patients with a total of 437 treatment-naive brain metastases from breast cancer were retrospectively reviewed. Patients were grouped according to the biological subtype of the tumor [luminal A, 28; luminal B, 9; human epidermal growth factor receptor 2 (HER2) positive, 14; triple-negative breast cancer (TNBC), 16]. All images were standardized to the human brain MRI atlas provided by the Montreal Neurological Institute 152 database. The distribution pattern of brain metastases after image standardization was analyzed. The cerebellum and the frontal lobe were more commonly affected by breast cancer brain metastases. Brain metastases from luminal A and B types of breast cancer arose more often in the cerebellum. Brain metastases from HER2-positive type breast cancer occurred more often in the putamen and the thalamus and less frequently in the cerebellum than other types (P=0.0057). The subtypes of breast cancer are related to differences in the spatial distributions of their brain metastases. These differences may be utilized to plan different cranial irradiation strategies according to the breast cancer subtypes.