Prognostic value of serum tartrate‑resistant acid phosphatase‑5b for bone metastasis in patients with resectable breast cancer

Bone metastasis significantly affects the quality of life of patients with metastatic breast cancer, and can shorten overall survival. Identifying patients with early-stage breast cancer at high risk for bone metastasis and preventing bone metastasis may lead to a better quality of life and prolonged survival. The present study investigated whether serum tartrate-resistant acid phosphatase-5b (TRACP-5b), a bone turnover marker, can be a prognostic factor for bone metastasis. Female patients who underwent resectable breast surgery between May 2002 and August 2006 were consecutively investigated. A total of 304 patients with a median follow-up of 3,722 days were retrospectively analyzed. TRACP-5b levels in sera prepared from patients' blood drawn preoperatively without any presurgical treatments were measured using an enzyme-linked immunosorbent assay. The cutoff of TRACP-5b levels, in order to separate patients into high and low TRACP-5b groups, was set at median (347 mU/dl). The associations of clinicopathological factors, including TRACP-5b, with bone metastasis-free interval (BMFI), which was defined as the duration between surgery and the diagnosis of bone metastasis at any time point, were examined. Multivariate analysis of various clinicopathological features revealed that lymph node metastasis and histological grade were independent factors associated with BMFI (P=0.017 and 0.030, respectively). In patients with node-positive breast cancer (n=114), a high TRACP-5b level and a high grade were significantly and independently associated with worse BMFI (log-rank P=0.041 and 0.011, respectively). In conclusion, these findings indicated that TRACP-5b may predict bone metastasis in patients with node-positive breast cancer.

High HER2 Intratumoral Heterogeneity Is a Predictive Factor for Poor Prognosis in Early-Stage and Locally Advanced HER2-Positive Breast Cancer

PURPOSE

Breast cancer tumors frequently have intratumoral heterogeneity (ITH). Tumors with high ITH cause therapeutic resistance and have human epidermal growth factor receptor 2 (HER2) heterogeneity in response to HER2-targeted therapies. This study aimed to investigate whether high HER2 heterogeneity levels were clinically related to a poor prognosis for HER2-targeted adjuvant therapy resistance in primary breast cancers.

METHODS

This study included patients with primary breast cancer (n = 251) treated with adjuvant HER2-targeted therapies. HER2 heterogeneity was manifested by the shape of HER2 fluorescence in situ hybridization amplification (FISH) distributed histograms with the HER2 gene copy number within a tumor sample. Each tumor was classified into a biphasic grade graph (high heterogeneity [HH]) group or a monophasic grade graph (low heterogeneity [LH]) group based on heterogeneity. Both groups were evaluated for disease-free survival (DFS) and overall survival (OS) for a median of ten years of annual follow-up.

RESULTS

Of 251 patients with HER2-positive breast cancer, 46 (18.3%) and 205 (81.7%) were classified into the HH and LH groups, respectively. The HH group had more distant metastases and a poorer prognosis than the LH group (DFS: p < 0.001 (HH:63% vs. LH:91% at 10 years) and for the OS: p = 0.012 (HH:78% vs. LH:95% at 10 years).

CONCLUSIONS

High HER2 heterogeneity is a poor prognostic factor in patients with HER2-positive breast cancer. A novel approach to heterogeneity, which is manifested by the shape of HER2 FISH distributions, might be clinically useful in the prognosis prediction of patients after HER2 adjuvant therapy.

Evaluation of RASSF1A methylation in the lysate of sentinel lymph nodes for detecting breast cancer metastasis: A diagnostic accuracy study

The restriction enzyme-based digital methylation-specific polymerase chain reaction (RE-dMSP) assay is useful for diagnosing sentinel lymph node (SN) metastasis in patients with breast cancer, by detecting tumor-derived methylated Ras association domain-containing protein 1 (RASSF1A). In addition, this assay has high concordance (95.0%) with one-step nucleic acid amplification (OSNA). The present study aimed to perform RE-dMSP using OSNA lysate from more patients and to re-evaluate its clinical usage. Overall, 418 SNs from 347 patients were evaluated using both OSNA and RE-dMSP. The concordance rate was 83.3% (348/418). RASSF1A methylation of the primary tumors was negative in 36 patients. When these patients were excluded, the concordance rate improved to 88.2% (330/374). Of the 79 OSNA-negative cases, 19 were RE-dMSP-positive, although all were positive for cytokeratin 19 expression in the primary tumor, suggesting that RE-dMSP can detect tumor-derived DNA with a higher sensitivity. The percent of methylated reference of the breast tumors showed a wide variety in the 16 OSNA-positive/RE-dMSP-negative cases, and such variability of methylation could have affected the results in these patients. In conclusion, although RE-dMSP can diagnose SN metastasis with high sensitivity and accuracy, and can be a supplementary tool to OSNA in breast cancer, RE-dMSP showed certain discordance with OSNA and critically depended on the absence or heterogeneity of DNA methylation in breast tumors. Further research is expected to develop an assay targeting other DNA alterations, such as mutations.

Initial Evaluation of [18F]FAPI-74 PET for Various Histopathologically Confirmed Cancers and Benign Lesions

The ¹⁸F-labeled fibroblast activation protein inhibitor (FAPI) [¹⁸F]FAPI-74 has the benefit of a higher synthetic yield and better image resolution than ⁶⁸Ga-labeled FAPI. We preliminarily evaluated the diagnostic performance of [¹⁸F]FAPI-74 PET in patients with various histopathologically confirmed cancers or suspected malignancies. Methods: We enrolled 31 patients (17 men and 14 women) with lung cancer (n = 7), breast cancer (n = 5), gastric cancer (n = 5), pancreatic cancer (n = 3), other cancers (n = 5), and benign tumors (n = 6). Twenty-seven of the 31 patients were treatment-naïve or preoperative, whereas recurrence was suspected in the remaining 4 patients. Histopathologic confirmation was obtained for the primary lesions of 29 of the 31 patients. In the remaining 2 patients, the final diagnosis was based on the clinical course. [¹⁸F]FAPI-74 PET scanning was performed 60 min after the intravenous injection of [¹⁸F]FAPI-74 (240 ± 31 MBq). The [¹⁸F]FAPI-74 PET images were compared between the primary or local recurrent lesions of malignant tumors (n = 21) and nonmalignant lesions (n = 8: type-B1 thymomas, granuloma, solitary fibrous tumor, and postoperative or posttherapeutic changes). The uptake and number of detected lesions on [¹⁸F]FAPI-74 PET were also compared with those on [¹⁸F]FDG PET for available patients (n = 19). Results: [¹⁸F]FAPI-74 PET showed higher uptake in primary lesions of various cancers than in nonmalignant lesions (median SUV_max, 9.39 [range, 1.83-25.28] vs. 3.49 [range, 2.21-15.58]; P = 0.053), but some of the nonmalignant lesions showed high uptake. [¹⁸F]FAPI-74 PET also showed significantly higher uptake than [¹⁸F]FDG PET (median SUV_max, 9.44 [range, 2.50-25.28] vs. 5.45 [range, 1.22-15.06] in primary lesions [P = 0.010], 8.86 [range, 3.51-23.33] vs. 3.84 [range, 1.01-9.75] in lymph node metastases [P = 0.002], and 6.39 [range, 0.55-12.78] vs. 1.88 [range, 0.73-8.35] in other metastases [P = 0.046], respectively). In 6 patients, [¹⁸F]FAPI-74 PET detected more metastatic lesions than [¹⁸F]FDG PET. Conclusion: [¹⁸F]FAPI-74 PET showed higher uptake and detection rates in primary and metastatic lesions than did [¹⁸F]FDG PET. [¹⁸F]FAPI-74 PET is a promising novel diagnostic modality for various tumors, especially for precise staging before treatment, including characterization of tumor lesions before surgery. Moreover, ¹⁸F-labeled FAPI ligand might serve a higher demand in clinical care in the future.

Detection of Ultra-Rare ESR1 Mutations in Primary Breast Cancer Using LNA-Clamp ddPCR

ESR1 mutations in breast cancer are one of the mechanisms of resistance to aromatase inhibitors. These mutations are common in metastatic breast cancer; however, these are rare in primary breast cancer. However, these data have been analyzed mainly in formalin-fixed, paraffin-embedded tissue; thus, rare mutations that may be present in primary breast cancer may be overlooked. In this study, we developed a highly sensitive mutation detection method called locked nucleic acid (LNA)-clamp droplet digital PCR (ddPCR) and validated it. The mutation detection sensitivity was substantiated to 0.003%. Then, we used this method to analyze ESR1 mutations in fresh-frozen (FF) tissues of primary breast cancer. cDNA extracted from the FF tissues of 212 patients with primary breast cancers were measured. Twenty-eight ESR1 mutations were found in twenty-seven (12.7%) patients. Sixteen (7.5%) patients had Y537S mutations and twelve (5.7%) had D538G mutations. Two mutations with a variant allele frequency (VAF) of ≥0.1% and twenty-six mutations with a VAF of <0.1% were found. By using this LNA-clamp ddPCR, this study demonstrated the presence of minor clones with a VAF of <0.1% in primary breast cancer.

Validation of the prognosis of patients with ER‑positive, HER2‑negative and node‑negative invasive breast cancer classified as low risk by Curebest™ 95GC Breast in a multi‑institutional registry study

Curebest™ 95GC breast (95GC) is a multigene classifier we developed for the prognostic prediction of patients with estrogen receptor (ER)-positive, human epidermal growth factor receptor 2 (HER2)-negative and node-negative (ER+/HER2-/n0) invasive breast cancer treated with adjuvant endocrine therapy alone. The aim of the preset study was to evaluate the clinical utility of 95GC in a multiinstitutional registry study. Patients (n=215) with ER⁺/HER2^-/n0 invasive breast cancer who had undergone the 95GC assay in seven hospitals were consecutively recruited in the registry study at various postoperative times. At recruitment, no patients had disease recurrences and were prospectively followed up for a median of 62 (range, 6-91) postoperative months. Of the 124 patients classified as 95GC low risk, 118 received adjuvant endocrine therapy alone and six received adjuvant chemo-endocrine therapy. Only two patients developed distant recurrences, and the 5-year distant recurrence-free survival (DRFS) was as high as 98.0%. Of the 91 patients classified as 95GC high risk, 81 received adjuvant chemo-endocrine therapy and 10 received adjuvant endocrine therapy alone. A total of four of these patients developed distant recurrences (5-year DRFS=95.5%). Among the 95GC high-risk patients, prognosis was significantly improved for the 81 treated with adjuvant chemo-endocrine therapy compared with for the 77 (historical controls) treated with adjuvant endocrine therapy alone (P=0.0002; hazard ratio, 0.24). Compared with the St. Gallen 2013 guideline, a significant de-escalation from 73.1% (155/212) to 40.6% (86/212) in adjuvant chemotherapy was achieved. The excellent prognosis of patients with ER⁺/HER2^-/n0 invasive breast cancer classified as 95GC low risk could be validated in the present registry study, indicating that 95GC is useful for safe de-escalation of adjuvant chemotherapy in patients with ER⁺/HER2^-/n0 invasive breast cancer.

Third-look contrast-enhanced ultrasonography plus needle biopsy for differential diagnosis of magnetic resonance imaging-only detected breast lesions

Research has shown that in approximately 20-30% of cases, breast lesions that were not detected on mammography (MG) or ultrasonography (US) were incidentally found during preoperative magnetic resonance imaging (MRI) examination for breast cancer. MRI-guided needle biopsy is recommended or considered for such MRI-only detected breast lesions invisible on second-look US, but many facilities in Japan cannot perform this biopsy procedure because it is expensive and time consuming. Thus, a simpler and more accessible diagnostic method is needed. Two studies to date have shown that third-look contrast-enhanced US (CEUS) plus needle biopsy for MRI-only detected breast lesions (i.e., MRI + /MG-/US-) that were not detected on second-look US showed moderate/high sensitivity (57.1 and 90.9%) and high specificity (100.0% in both studies) with no severe complications. In addition, the identification rate was higher for MRI-only lesions with a higher MRI BI-RADS category (i.e., category 4/5) than for those with a lower category (i.e., category 3). Despite the fact that there are limitations in our literature review, CEUS plus needle biopsy is a feasible and convenient diagnostic tool for MRI-only lesions invisible on second-look US and is expected to reduce the frequency of MRI-guided needle biopsy. When third-look CEUS does not reveal MRI-only lesions, a further indication for MRI-guided needle biopsy should be considered according to the BI-RADS category.

WT1 Trio Peptide-Based Cancer Vaccine for Rare Cancers Expressing Shared Target WT1

No standard treatment has been established for most rare cancers. Here, we report a clinical trial of a biweekly WT1 tri-peptide-based vaccine for recurrent or advanced rare cancers. Due to the insufficient number of patients available for a traditional clinical trial, the trial was designed for rare cancers expressing shared target molecule WT1. The recruitment criteria included WT1-expressing tumors as well as HLA-A*24:02 or 02:01. The primary endpoints were immunoglobulin G (IgG) antibody (Ab) production against the WT1-235 cytotoxic T lymphocyte (CTL) epitope and delayed-type hypersensitivity (DTH) skin reactions to targeted WT1 CTL epitopes. The secondary endpoints were safety and clinical efficacy. Forty-five patients received WT1 Trio, and 25 (55.6%) completed the 3-month protocol treatment. WT1-235 IgG Ab was positive in 88.0% of patients treated with WT1 Trio at 3 months, significantly higher than 62.5% of the weekly WT1-235 CTL peptide vaccine. The DTH positivity rate in WT1 Trio was 62.9%, which was not significantly different from 60.7% in the WT1-235 CTL peptide vaccine. The WT1 Trio safety was confirmed without severe treatment-related adverse events, except grade 3 myasthenia gravis-like symptoms observed in a patient with thymic cancer. Fifteen (33.3%) patients achieved stable disease after 3 months of treatment. In conclusion, the biweekly WT1 Trio vaccine containing the WT1-332 helper T lymphocyte peptide induced more robust immune responses targeting WT1 than the weekly WT1-235 CTL peptide vaccine. Therefore, WT1-targeted immunotherapy may be a potential therapeutic strategy for rare cancers.

Hypercalcemia affected in metastatic breast cancer patients without bone metastasis: report of three cases

Background

Since humoral hypercalcemia of malignancy (HHM) in breast cancer patients without bone metastasis is rare, the clinical features of this condition are not fully understood.

Case presentation

During the recent 12 years, 3602 patients were diagnosed with breast cancer in our institution, and only three patients developed HHM without bone metastasis. They were all recurrent breast cancer patients with visceral metastases including the lung and the liver. It took no more than 2 months since symptomatic onset to hospitalization because of hypercalcemia. The maximum serum calcium concentrations were 15.0 mg/dL or higher. All patients had symptoms related to hypercalcemia. Treatment of hypercalcemia including hydration, calcitonin, bisphosphonate, and diuretics was initially effective in the three patients. However, two of three cases were eventually fatal because of unsuccessful treatment of breast cancer.

Conclusions

The common features of HHM without bone metastasis in breast cancer patients include acute onset, severe symptomatic hypercalcemia, and presence of visceral metastasis. Treatment of hypercalcemia decreased serum calcium level in a short period, while successful treatment of breast cancer was essential for a long-term management of HHM. This report provides a consideration to help elucidate the pathophysiology and medical care of breast cancer patients with HHM without bone metastasis.

Proton Pump Inhibitors Ameliorate Capecitabine-induced Hand-Foot Syndrome in Patients With Breast Cancer: A Retrospective Study

BACKGROUND/AIM

Hand-foot syndrome (HFS) is the most common adverse event associated with capecitabine, and its pathogenesis is known to be associated with inflammation. Proton pump inhibitors (PPIs) reportedly exert anti-inflammatory effects; however, the impact of PPIs on capecitabine-induced HFS needs to be clarified in the clinical setting. In the present study, we retrospectively investigated the efficacy and safety of PPIs in patients with breast cancer receiving capecitabine.

PATIENTS AND METHODS

We analyzed the effects of PPIs on the development of severe HFS (grade ≥2), progression-free survival (PFS), and overall survival (OS) in 195 patients who received capecitabine chemotherapy for breast cancer.

RESULTS

In total, 50 patients (26%) were treated with PPIs, while 145 patients (74%) did not receive PPIs. The incidence of severe HFS was significantly lower in patients who received PPIs (18%) than in patients who did not receive PPIs (43%, p=0.001), and the discontinuation rate of capecitabine therapy due to HFS was also lower in patients receiving PPIs than in those who did not receive PPIs (p=0.003). Multivariate analysis revealed that concomitant PPIs use was an independent factor that significantly contributed to the prevention of severe HFS (odds ratio (OR)=0.265, p=0.003). Meanwhile, no significant difference in median PFS and OS values was observed between patients treated with and without PPIs.

CONCLUSION

Concomitant use of PPIs could ameliorate capecitabine-induced HFS in patients with breast cancer.

A prediction model for early systemic recurrence in breast cancer using a molecular diagnostic analysis of sentinel lymph nodes: A large-scale, multicenter cohort study

BACKGROUND

The one-step nucleic acid amplification (OSNA) assay can quantify the cytokeratin 19 messenger RNA copy number as a proxy for sentinel lymph node (SN) metastasis in breast cancer. A large-scale, multicenter cohort study was performed to determine the prognostic value of the SN tumor burden based on a molecular readout and to establish a model for the prediction of early systemic recurrence in patients using the OSNA assay.

METHODS

SN biopsies from 4757 patients with breast cancer were analyzed with the OSNA assay. The patients were randomly assigned to the training or validation cohort at a ratio of 2:1. On the basis of the training cohort, the threshold SN tumor burden value for stratifying distant recurrence was determined with Youden's index; predictors of distant recurrence were investigated via multivariable analyses. Based on the selected predictors, a model for estimating 5-year distant recurrence-free survival was constructed, and predictive performance was measured with the validation cohort.

RESULTS

The prognostic cutoff value for the SN tumor burden was 1100 copies/μL. The following variables were significantly associated with distant recurrence and were used to construct the prediction model: SN tumor burden, age, pT classification, grade, progesterone receptor, adjuvant cytotoxic chemotherapy, and adjuvant anti-human epidermal growth factor receptor 2 therapy. The values for the area under the curve, sensitivity, specificity, and accuracy of the prediction model were 0.83, 63.4%, 81.7%, and 81.1%, respectively.

CONCLUSIONS

Using the OSNA assay, the molecular readout-based SN tumor burden is an independent prognostic factor for early breast cancer. This model accurately predicts early systemic recurrence and may facilitate decision-making related to treatment.

A case of sternal osteomyelitis during treatment with everolimus for recurrent breast cancer

Background

Everolimus is a mechanistic-target-of-rapamycin (mTOR) inhibitor bearing a potent antitumor effect against hormone receptor-positive breast cancer. Here, we report the case of a patient with recurrent breast cancer who developed osteomyelitis during the treatment with everolimus plus exemestane.

Case presentation

A 56-year-old woman with early-stage breast cancer underwent right mastectomy and axillary lymph node dissection at the age of 45. Four years after the surgery, she experienced relapse at the chest wall. Radiotherapy was performed on the chest wall, including the sternum, and denosumab was administered. After several regimens of hormonal therapies, everolimus in combination with exemestane was administered. Three months later, the patient visited our clinic because of continuous fever. A computed tomography scan showed an osteolytic change in the sternal bone with pneumomediastinum, which indicated sternal osteomyelitis. Extensive debridement followed by secondary reconstruction of the chest wall was successfully performed.

Conclusions

Everolimus may cause osteomyelitis of the affected bone as a result of tumor necrosis. Everolimus-induced osteomyelitis may be manageable by extensive debridement performed without delay.

Alpha-crystallin B chains in trastuzumab-resistant breast cancer cells promote endothelial cell tube formation through activating mTOR

The specific human epidermal growth factor receptor 2 (HER2)-targeting monoclonal antibody trastuzumab shows considerable clinical efficacy in patients with HER2-overexpressing breast cancer. However, about 20% of patients who receive trastuzumab in the adjuvant setting relapse, and approximately half of patients with metastatic HER2-positive breast cancer develop resistance to trastuzumab within 1 year. Although the mechanism of trastuzumab resistance has been explored broadly, whether and how angiogenesis participates in trastuzumab resistance is unclear. Here, we examined the association between angiogenesis and trastuzumab resistance by using a trastuzumab-resistant cell line (SKBR3-TR). Compared with that from the parental trastuzumab-sensitive SKBR3 cells, the culture supernatant from SKBR3-TR cells significantly increased the sprouting of endothelial cells. To identify intercellular features that contribute to the induction of endothelial tube formation, proteomics revealed that α-crystallin B chain (αB-crystallin) was upregulated in SKBR3-TR cells. Moreover, silencing of αB-crystallin significantly repressed SKBR3-TR-induced tube formation, and knockdown of αB-crystallin in SKBR3-TR cells suppressed the activation of mechanistic target of rapamycin (mTOR) in endothelial cells. In addition, treatment with rapamycin, an inhibitor of mTOR, reversed the SKBR3-TR-induced promotion of tube formation. In summary, αB-crystallin enhanced the ability of SKBR3-TR cells to activate mTOR in endothelial cells and thus promote angiogenesis.

Periostin Exon-21 Antibody Neutralization of Triple-Negative Breast Cancer Cell-Derived Periostin Regulates Tumor-Associated Macrophage Polarization and Angiogenesis

Simple Summary

Despite remarkable advances in breast cancer treatment, few strategies other than standard cytotoxic chemotherapy are available for patients with triple-negative breast cancer (TNBC) due to the lack of therapeutic target molecules. TNBC is still the most aggressive subtype, with a high risk of recurrence and metastasis within 2 years after initial treatment. Thus, there is an unmet medical need to develop new treatments for metastatic and recurrent TNBC patients. In this study we tested a new antibody, targeting extracellular periostin protein alternative splicing variants, which are induced by conventional chemotherapy or during the process of endothelial mesenchymal transition. This antibody reduced periostin-secreting TNBC in a mouse xenograft model, accompanied by a decrease in the number of M2 tumor-associated macrophages and tumor vessels. Periostin alternative splicing variants might be a specific and safe therapeutic target in patients with TNBC.

Abstract

Periostin (Pn) is involved in multiple processes of cancer progression. Previously, we reported that Pn expression is correlated with mesenchymal tumor markers and poor prognosis in triple-negative breast cancer (TNBC). In the TNBC xenograft model, chemotherapy increased expression of a Pn alternative splicing variant (ASV) with exon 21, and administration of the neutralizing antibody against Pn with exon 21 (Pn-21 Ab) overcame chemoresistance with a reduction in the mesenchymal cancer cell fraction. In the present study, the role of Pn ASV with exon 21 in TNBC progression has been addressed. We first established a stable cell line carrying a fluorescence-based splicing reporter. Pn-positive TNBC has higher expression of genes related to tumor-associated macrophage (TAM) recruitment and ECM-receptor interaction than Pn-negative cells. In a xenograft model, only Pn-positive cells initiated tumor formation, and the Pn-21 Ab suppressed tumor cell growth, accompanied by decreased M2 TAM polarization and the number of tumor vessels. These data suggest that cancer cell-derived Pn ASV educates TAMs and regulates angiogenesis, which in turn establishes a microenvironmental niche that is supportive of TNBC.

Comparison of the multigene panel test and OncoScan™ for the determination of HER2 amplification in breast cancer

The diagnostic accuracy of the multigene panel test (MPT) and OncoScan™ in the determination of HER2 amplification in breast tumors remains controversial. In the present study, HER2 copy number was analyzed using both MPT and OncoScan™ in 45 breast tumors and was compared with that in fluorescent in situ hybridization (FISH) analysis. Tumors with low cellularity were examined using tumor cell enrichment and fluorescence‑activated cell sorting. Both MPT and OncoScan™ exhibited significant correlations with FISH with respect to the determination of HER2 amplification in breast tumors. However, the correlation coefficient was significantly higher for the comparison of MPT and FISH (r=0.770) compared with that between OncoScan™ and FISH (r=0.564). The accuracy of MPT (93.3%) was slightly higher compared with that in OncoScan™ (84.4%) in determining the HER2 status, which was mostly explained by the higher sensitivity of MPT in tumors with low cellularity (83.3 vs. 33.3%), but not in those with high cellularity (81.8 vs. 72.7%). The specificity was 100% for both tests. The MPT exhibited higher sensitivity in the determination of the amplification of other genes, including MYC, fibroblast growth factor receptor 1 and GATA binding protein 3 in tumors with low cellularity compared with that in tumors with high cellularity. OncoScan™ exhibited low sensitivity without tumor cell enrichment. The results suggested that MPT could be a promising method to determine HER2 status in breast tumors and that it could exhibit improved accuracy compared with that in OncoScan™ in tumors with low cellularity.

Periostin Short Fragment with Exon 17 via Aberrant Alternative Splicing Is Required for Breast Cancer Growth and Metastasis

BACKGROUND

Periostin (POSTN) is a 93 kDa matrix protein that helps to regulate collagen gene expression in the extracellular matrix. POSTN overexpression is a prognostic factor in malignant cancers; however, some researchers have observed it in the stroma, whereas others have reported it on tumors.

OBJECTIVE

This study aimed to investigate the function of POSTN on tumors.

METHODS AND RESULTS

We found that POSTN in cancer cells can be detected by using an antibody against the POSTN C-terminal region exon 17 (Ex17 antibody), but not with an antibody against the POSTN N-terminal region exon 12 (Ex12 antibody) in patients with breast cancer. In a fraction secreted from fibroblasts, LC-MS/MS analysis revealed a short fragment of POSTN of approximately 40 kDa with exon 17. In addition, molecular interaction analysis showed that POSTN with exon 17, but not POSTN without exon 17, bound specifically to wnt3a, and the Ex17 antibody inhibited the binding.

CONCLUSION

A short fragment of POSTN with exon 17, which originates in the fibroblasts, is transported to cancer cells, whereas POSTN fragments without exon 17 are retained in the stroma. The Ex17 antibody inhibits the binding between POSTN exon 17 and wnt3a.

Aesthetic utility of addition of nipple-areola recentralization to rotation flap according to nipple tumor distance for patients with lower-outer or upper-inner located breast cancers

We aimed to validate the cosmetic utility of addition of nipple-areola recentralization (NAR) to rotation flap according to nipple tumor distance (NTD) as a volume displacement technique after breast conserving surgery (BCS) for lower-outer and upper-inner breast cancers. Twenty breast cancer patients who had been treated with rotation flap with (Group 1; n = 6) or without (Group 2; n = 14) NAR after BCS for lower-outer or upper-inner located tumors, and those who had undergone BCS without oncoplastic surgical technique for tumors in the same area (Control group; n = 43), were retrospectively investigated. Cosmetic outcome was evaluated using Harvard scale and/or BCCT.core. As a result, the ratio of patients categorized as excellent/good was 83% in Group 1 and 93% in Group 2, respectively, and there was no significant difference between them (P = 0.521). In addition, Group 1 + 2 showed a significantly higher ratio of patients classified as excellent/good than the control group (90% vs. 56%; P = 0.009). After adjustment of clinical background parameters using propensity score matching analysis between Group 1 + 2 and the control group, 12 pairs with similar background factors were matched. Among them, Group 1 + 2 showed a higher ratio of patients categorized as excellent/good than the control group (92% vs. 42%; P = 0.034). In conclusion, addition of NAR to rotation technique according to NTD may enable us to perform a volume displacement after BCS for lower-outer or upper-inner located tumors irrespective of NTD without sacrificing postoperative breast appearance.

Prediction of pathological complete response after neoadjuvant chemotherapy in breast cancer: comparison of diagnostic performances of dedicated breast PET, whole-body PET, and dynamic contrast-enhanced MRI

PURPOSE

To compare the diagnostic performance of ring-type dedicated breast PET (dbPET), whole-body PET (WBPET), and DCE-MRI for predicting pathological complete response (pCR) after neoadjuvant chemotherapy (NAC).

METHODS

This prospective study included 29 women with histologically proven breast cancer on needle biopsy between July 2016 and July 2019 (age: mean 55 years; range 35-78). Patients underwent WBPET followed by ring-type dbPET and DCE-MRI pre- and post-NAC for preoperative evaluation. pCR was defined as an invasive tumor that disappeared in the breast. Standardized uptake values corrected for lean body mass (SULpeak) were calculated for dbPET and WBPET scans. Maximum tumor length was measured in DCE-MRI images. Reduction rates were calculated for quantitative evaluation. Two radiologists independently evaluated the qualitative findings. Reduction rates and qualitative findings were compared between the pCR (n = 7) and non-pCR (n = 22) groups for each modality. Differences in quantitative and qualitative data between the two groups were analyzed statistically.

RESULTS

Significant differences were observed in the reduction rates of dbPET and DCE-MRI (P = 0.01 and 0.03, respectively) between the two groups. Univariate and multiple logistic regression analyses revealed that SULpeak reduction rates in WBPET and dbPET (P = 0.02 and P = 0.01, respectively) and in dbPET (odds ratio, 16.00; 95% CI 1.57-162.10; P = 0.01) were significant indicators associated with pCR, respectively. No between-group differences were observed in qualitative findings in the three modalities.

CONCLUSION

SULpeak reduction rate of dbPET > 82% was an independent indicator associated with pCR after NAC in breast cancer.

The multigene classifiers 95GC/42GC/155GC for precision medicine in ER-positive HER2-negative early breast cancer

In clinical decision‐making, to decide the indication for adjuvant chemotherapy for estrogen receptor‐positive (ER+), human epidermal growth factor receptor‐2‐negative (HER2−), and node‐negative (n0) breast cancer patients, the accurate estimation of recurrence risk is essential. Unfortunately, conventional prognostic factors, such as tumor size, histological grade and ER, progesterone receptor (PR), and HER2 status as well as Ki67 index, are not sufficiently accurate for such estimation. Therefore, several multigene assays (MGAs) based on the mRNA expression analysis of multiple genes in tumor tissue have been developed to better predict patient prognosis. These assays include Oncotype DX, MammaPrint, PAM50, GGI, EndoPredict, and BCI. We developed Curebest™ 95‐Gene Classifier Breast (95GC) classifier, which is unique in that mRNA expression data of all 20 000 human genes are secondarily obtainable, as the 95GC assay is performed using Affymetrix microarray. This can capture mRNA expression of not only 95 genes but also every gene at once, and such gene expression data can be utilized by the other MGAs that we have developed, such as the 155GC, which is used for the prognostic prediction of ER+/HER2− breast cancer patients treated with neoadjuvant chemotherapy. We also developed the 42GC for predicting late recurrence in ER+/HER2− breast cancer patients. In this mini‐review, our recent attempt at the development of various MGAs, which is expected to facilitate the implementation of precision medicine in ER+/HER2− breast cancer patients, is presented with a special emphasis on 95GC.

Impact of tumor cellularity on the HER2 amplification assay by OncoScan™ in breast cancer

HER2 amplification is seen in 20-25% of primary breast cancer cases, and HER2 detection is performed routinely in primary operable, as well as metastatic breast cancer patients. Currently, HER2 is the only gene of which amplification is routinely assayed by fluorescent in situ hybridization (FISH) and/or immunohistochemistry (IHC). However, histochemical assay (FISH/IHC) of multiple target genes is laborious and time-consuming, and simultaneous amplification by microarray is preferred. OncoScan™ is a microarray-based assay capable of whole-genome copy number analysis using DNA extracted from formalin-fixed paraffin-embedded (FFPE) tissues. In the current study, we aimed to investigate the impact of tumor cellularity on the accuracy of OncoScan™ in the determination of HER2 amplification. Our results demonstrated that HER2 amplification by OncoScan™ is accurate, and has a high concordance rate of 93.3% with FISH. However, the concordance rate is poor (66.7%) in cases with a tumor cellularity < 20%. Nevertheless, the addition of FISH to breast tumors with a tumor cellularity < 20% and a HER2 copy number of 4 appears to be useful to minimize false-negative results by OncoScan™.

Determining homologous recombination deficiency scores with whole exome sequencing and their association with responses to neoadjuvant chemotherapy in breast cancer

Recent studies demonstrated that homologous repair deficiency (HRD) score is a useful marker for response to poly (ADP-ribose) polymerase inhibitors or platinum-based chemotherapy. We determined HRD scores and elucidated the clinicopathologic characteristics of HRD-high tumors and their response to non-platinum-based chemotherapy. Primary breast cancer patients (n = 120) were pre-operatively treated with paclitaxel followed by 5-fluorouracil/epirubicin/cyclophosphamide (P-FEC). Germline and somatic homologous recombination related gene mutations (gHRRm and sHRRm, respectively) and HRD scores were analyzed using whole exome sequencing (WES) in tumor tissues obtained before chemotherapy. Of 120 tumors, 30 were determined to be HRD-high tumors, significantly associated with high Ki-67 (P = 0.014), ER negativity (P = 0.007), and PR negativity (P = 0.021). Triple-negative cancers showed significantly higher HRD scores than the luminal, luminal-HER2, and HER2 subtypes (P = 0.023, 0.016, and 0.033, respectively). HRD scores were significantly higher in tumors with gHRRm than in those with sHRRm (P = 0.002) or wild-type HRR genes (P = 1.44e-4), but no significant difference was found in HRD scores between tumors with sHRRm and wild-type HRR genes (P = 0.206). HRD-high tumors had significantly (P = 0.003) higher pCR rates and higher near-pCR rates (P = 0.049) compared with those of the HRD-low tumors in all tumors and the luminal subtype, respectively. HRD-high tumors were associated with aggressive phenotypes and gHRRm, but not sHRRm. Our findings suggested that HRD scores might be useful in predicting response to P-FEC in the luminal subtype.

Enhanced humoral immunity in breast cancer patients with high serum concentration of anti-HER2 autoantibody

Humoral immunity plays a substantial role in the suppression of breast cancer. We have revealed that a high serum concentration of anti‐HER2 autoantibody (HER2‐AAb) is associated with favorable outcomes in patients with invasive breast cancer. Thus, we aimed to clarify the association between high serum concentration of HER2‐AAb and humoral immune response in the tumor microenvironment. Out of 500 consecutive patients with invasive breast cancer, we selected those whose HER2‐AAb values were high (n = 33) or low (n = 20) based on the distribution of HER2‐AAb values of 100 healthy individuals. Tumor and regional lymph node formalin‐fixed paraffin‐embedded samples prepared from the surgical specimens were subjected to immunohistochemistry. We confirmed that the recurrence‐free survival of the high HER2‐AAb group was significantly longer than that of the low HER2‐AAb group (p = 0.015). The numbers of tumor‐infiltrating CD20+ immune cells (ICs) (p < 0.001), IGKC+ICs (p = 0.023), and CXCL13+ ICs (p = 0.044) were significantly higher in the high HER2‐AAb group than in the low HER2‐AAb group. The number of CD4+ ICs in the B‐cell follicles of the regional lymph nodes was also significantly greater in the high HER2‐AAb group than in the low HER2‐AAb group (p = 0.026). Our findings indicate that a high level of HER2‐AAb is associated with enhanced humoral immunity against breast cancer and thus may provide a rationale for the association of HER2‐AAb with favorable prognosis.

Sentinel lymph node biopsy after introducing Twirl® breast markers into suspicious lymph nodes in breast cancer patients

Ten stage I/II breast cancer patients with one or two suspicious lymph nodes (LNs) detected on ultrasonography underwent sentinel LN biopsy (SLNB) after the introduction of Twirl® breast markers into each suspicious LN revealed that each Twirl®-marked LN was SLN and was likely the first SLN. Three patients had less than three SLN metastases and were candidates for sparing completion axillary lymph node dissection (cALND). Indeed, of them, one underwent breast-conserving surgery without cALND and the other two underwent total mastectomy with cALND. These results suggest that, as all suspicious LNs are SLNs, patients can be treated with SLNB alone if they fulfill the ACOSOG Z-0011 criteria, despite suspicious LNs yielding positive results on preoperative fine-needle aspiration cytology.

Effect of Computer-aided Detection System Use on the Duration of MRI-guided Biopsy of the Breast

BACKGROUND/AIM

Magnetic resonance imaging (MRI)-guided breast biopsy is a complex and time-consuming procedure. This study aimed to clarify the factors that affect the duration of the procedure.

PATIENTS AND METHODS

Twenty-eight examinations performed at our institute for 27 lesions detected solely on MRI were analyzed. The correlations between the clinicopathological factors and duration of the procedure were estimated.

RESULTS

The needle guidance method was the only factor that significantly affected the duration of the MRI-guided vacuum-assisted breast biopsy (VAB) (p=0.012). The use of a computer-aided detection (CAD) system with grid breast compression plates had significantly shorter durations (62±12 min) than the manual calculation of coordinates with pillar-type compression plates (76±13 min).

CONCLUSION

This preliminary study showed that the use of a CAD system might shorten the duration of MRI-guided VAB.

Abstract 1604: Association of autoantibodies to HER2 with tumor microenvironments for humoral immunity and prognosis in patients with breast cancer

AIM: We have previously reported that the serum concentration of anti-HER2 autoantibodies (HER2-AAb) is associated with favorable outcomes in patients with invasive breast cancer (Tabuchi et al., Breast Cancer Res Treat 157:55-63, 2016). This study aimed to investigate the prognostic impact of HER2-AAb by examining the tumor microenvironments for humoral immunity.

PATIENTS AND METHODS: From 500 consecutive patients with invasive breast cancer (Ibid.), we selected those whose log-transformed HER2-AAb values were above mean + 2SD (high HER2-AAb group, N = 33) or below mean − 2SD (low HER2-AAb group, N = 20). Tumor formalin-fixed paraffin-embedded (FFPE) samples and regional lymph node FFPE samples prepared from the patients’ surgical specimens were subjected to immunohistochemistry. Tumor-infiltrating immune cells (ICs) localized inside the tumor, in the adjacent stroma, and in the tumor stroma were separately counted. Expression of some proteins in tumor cells (TCs) was evaluated by the percentages of tumor cells showing presence of those proteins.

RESULTS: We confirmed in the selected patients that the recurrence-free interval of the high HER2-AAb group was significantly longer than that of the low HER2-AAb group (log-rank P = 0.017; hazard ratio = 0.12). Tumor-infiltrating CD20-positive ICs (intratumoral + adjacent stromal ICs, P &lt; 0.001), IGKC-positive ICs (intratumoral + adjacent stromal ICs, P = 0.023), and CXCL13-positive ICs (total ICs, P = 0.044) were significantly greater in the high HER2-AAb group than in the low HER2-AAb group. CD4-positive ICs in B-cell follicles of the regional lymph nodes were also significantly greater in the high HER2-AAb group than in the low HER2-AAb group (P = 0.026). Tumor-infiltrating PD-L1-positive ICs, CD8-positive ICs, FOXP3-positive ICs, as well as CD8/FOXP3 ratios, were not significantly different between the two groups. The expression of CXCL13, HLA-A/B/C, and PD-L1 in TCs was not significantly different between the two groups. The repertoire of B-cell receptors in ICs was not significantly different between the two groups but was considered to be skewed. HER2 expression and gene amplification and the existence of HER2 missense mutations were similar between the two groups.

CONCLUSIONS: Increased HER2-AAb concentration was associated with enhanced humoral immunity in tumor microenvironments. Our findings indicate that a patient subpopulation with enhanced humoral immunity protecting against breast cancer recurrence exists. The recognition site of HER2-AAb may not be located in the HER2 polypeptide, but may be located in modifying factors, such as sugar chains.

Citation Format: Masafumi Shimoda, Yasufumi Sato, Yoshiaki Sota, Tomohiro Miyake, Tomonori Tanei, Naofumi Kagara, Yasuto Naoi, Kenzo Shimazu, Seung Jin Kim, Shinzaburo Noguchi. Association of autoantibodies to HER2 with tumor microenvironments for humoral immunity and prognosis in patients with breast cancer [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 1604.

Development of Prediction Model Including MicroRNA Expression for Sentinel Lymph Node Metastasis in ER-Positive and HER2-Negative Breast Cancer

BACKGROUND

The aim of our study is to find microRNAs (miRNAs) associated with sentinel lymph node metastasis (SLNM) and to develop a prediction model for SLNM in ER-positive and HER2-negative (ER+/HER2-) breast cancer.

PATIENTS AND METHODS

In the present study, only ER+/HER2- primary breast cancer was considered. The discovery set for SLNM-associated miRNAs included 10 tumors with and 10 tumors without SLNM. The training and validation sets both included 100 tumors. miRNA expression in tumors was examined comprehensively by miRNA microarray in the discovery set and by droplet digital PCR in the training and validation sets.

RESULTS

In the discovery set, miR-98, miR-22, and miR-223 were found to be significantly (P < 0.001, fold-change > 2.5) associated with SLNM. In the training set, we constructed the prediction model for SLNM using miR-98, tumor size, and lymphovascular invasion (LVI) with high accuracy (AUC, 0.877). The accuracy of this prediction model was confirmed in the validation set (AUC, 0.883), and it outperformed the conventional Memorial Sloan Kettering Cancer Center nomogram. In situ hybridization revealed the localization of miR-98 expression in tumor cells.

CONCLUSIONS

We developed a prediction model consisting of miR-98, tumor size, and LVI for SLNM with high accuracy in ER+/HER2- breast cancer. This model might help decide the indication for SLN biopsy in this subtype.

Emerging Technologies for Real-Time Intraoperative Margin Assessment in Future Breast-Conserving Surgery

Clean surgical margins in breast-conserving surgery (BCS) are essential for preventing recurrence. Intraoperative pathologic diagnostic methods, such as frozen section analysis and imprint cytology, have been recognized as crucial tools in BCS. However, the complexity and time-consuming nature of these pathologic procedures still inhibit their broader applicability worldwide. To address this situation, two issues should be considered: 1) the development of nonpathologic intraoperative diagnosis methods that have better sensitivity, specificity, speed, and cost; and 2) the promotion of new imaging algorithms to standardize data for analyzing positive margins, as represented by artificial intelligence (AI), without the need for judgment by well-trained pathologists. Researchers have attempted to develop new methods or techniques; several have recently emerged for real-time intraoperative management of breast margins in live tissues. These methods include conventional imaging, spectroscopy, tomography, magnetic resonance imaging, microscopy, fluorescent probes, and multimodal imaging techniques. This work summarizes the traditional pathologic and newly developed techniques and discusses the advantages and disadvantages of each method. Taking into consideration the recent advances in analyzing pathologic data from breast cancer tissue with AI, the combined use of new technologies with AI algorithms is proposed, and future directions for real-time intraoperative margin assessment in BCS are discussed.

Highly sensitive detection of sentinel lymph node metastasis of breast cancer by digital PCR for RASSF1A methylation

One-step nucleic acid amplification (OSNA) targeting cytokeratin 19 (CK19) mRNA expression and pathological examination are widely used for the intraoperative diagnosis of sentinel node (SN) metastasis. The aim of the present study was to develop a novel assay for detecting SN metastasis by targeting Ras association domain-containing protein 1 (RASSF1A) methylation in tumor cells, and to compare its performance with OSNA. Using digital PCR with methylation-specific restriction enzymes (RE-dMSP), our assay was able to detect ≥3 copies of methylated DNA per well, and was ≥10 times more sensitive than real-time PCR with bisulfite modification. OSNA lysates were examined using RE-dMSP and digital PCR for PIK3CA mutation, in the event that primary tumors were PIK3CA mutation-positive. RE-dMSP revealed a high concordance of 95.0% (153/161) with OSNA, and 100% (59/59) with PIK3CA mutation for detecting SN metastasis. In 11 breast cancer cell lines, the variation in methylated RASSF1A copy number was significantly lower than that of CK19 mRNA (2.8 vs. 10.5-fold; P<0.01). RE-dMSP has the potential to more accurately detect SN metastasis, and to more precisely estimate total tumor loads in SN, compared with OSNA.

Development of recurrence risk score using 95‑gene classifier and its application to formalin‑fixed paraffin‑embedded tissues in ER‑positive, HER2‑negative and node‑negative breast cancer

We previously developed a 95‑gene classifier (95GC) to classify ER‑positive/HER2‑negative/node‑negative (ER+/HER2‑/N0) breast cancer as high‑ and low‑risk. The present study aimed to devise a 95GC recurrence score (95GCRS) to estimate recurrence risk more precisely and, although the 95GC was originally developed using fresh‑frozen (FF) tissues, this was applied to formalin‑fixed paraffin‑embedded (FFPE) tissues. 95GCRS was calculated using between‑group analysis and denominated as a value from 0 to 100. Correlation of 95GCRS with distant recurrence rate and response to neoadjuvant chemotherapy (NAC) was evaluated in 257 patients with ER+/HER2-/N0 breast cancer treated with adjuvant hormonal therapy at Osaka University Hospital and in 425 patients with ER+ breast cancer treated with NAC at Osaka University Hospital and the University of Texas MD Anderson Cancer Center (GSE25066 dataset). Correlation of 95GCRS between FF and FFPE tissues was evaluated in paired tissues from 56 ER+/HER2‑/N0 breast cancer types obtained from patients without NAC treatment. Distant recurrence rates were remarkably low in patients with 95GCRS ≤50 and increased proportionally in patients with 95GCRS >50. Pathological complete response (pCR) rates to NAC were increased in proportion to 95GCRS, indicating a greater sensitivity of breast cancers with high 95GCRS to chemotherapy. 95GCRS was highly correlated (R=0.92) between FF and FFPE tissues, and the concordance rate (94.6%) of high‑ and low‑risk groups was also considerably high. Overall, the present study developed a 95GCRS that correlated with distant recurrence rate and pCR rate to NAC. The 95GC was applicable to FFPE tissues with a high concordance rate in FF tissues.

Real-Time Visualization of Lymphatic Flow to Sentinel Lymph Nodes by Contrast-Enhanced Ultrasonography with Sonazoid in Patients with Breast Cancer

Contrast-enhanced ultrasonography with Sonazoid (SNZ) enables real-time visualization, resulting in more precise identification of lymphatic flow to sentinel lymph nodes (SLNs). This study aimed to classify lymphatic drainage patterns to SLNs. Patients (n = 75) with T1-2 N0 M0 breast cancer received a periareolar injection of SNZ to identify SNZ-enhanced SLNs (SNZ-SLNs), followed by SLN biopsy with blue dye. The lymphatic drainage patterns were classified into four types: type A, single lymphatic route/single SLN; type B, multiple lymphatic routes/single SLN; type C, single lymphatic route/multiple SLNs; and type D, multiple lymphatic routes/multiple SLNs. SLNs were successfully identified in all patients using both blue dye and SNZ. The drainage lymphatic pathways identified were as follows: type A in 53 cases (70.7%), type B in seven (9.3%), type C in eight cases (10.7%) and type D in seven (9.3%). SNZ-SLN biopsy is a technically simple method with a 100% identification rate, enabling the real-time visualization of lymphatic flow to SNZ-SLNs.

Vasculogenic mimicry is associated with trastuzumab resistance of HER2-positive breast cancer

Background

Trastuzumab is a drug that targets the receptor tyrosine kinase HER2 and is essential for the treatment of HER2-positive breast cancer. Resistance to the drug leads to severe consequences, including disease recurrence, tumor enlargement, and metastasis. We hypothesized that trastuzumab treatment might be associated with phenotypic switching in HER2-positive breast cancer cells (BCCs), enabling them to escape and survive the effect of trastuzumab.

Methods

We conducted comprehensive immunophenotyping to detect phenotypic changes in HER2-positive BCCs treated with trastuzumab, based on criteria determined a priori. Based on immunophenotyping results, we characterized the vascular phenotypes of HER2-positive BCCs by western blotting, real-time RT-PCR, and tube formation assay. The vascular phenotype of tumor cells from clinical samples was evaluated by staining with periodic acid-Schiff and an anti-CD31 antibody. We explored small molecule inhibitors that suppress tube formation and determined the inhibitory mechanism.

Results

Out of 242 cell surface antigens, 9 antigens were significantly upregulated and 3 were significantly downregulated by trastuzumab treatment. All upregulated antigens were related to endothelial and stem cell phenotypes, suggesting that trastuzumab treatment might be correlated to switching to a vascular phenotype, namely, vasculogenic mimicry (VM). Several VM markers were upregulated in trastuzumab-treated cells, but these cells did not form tubes on Matrigel, a functional hallmark of VM. Upon analysis of three trastuzumab-resistant HER2-positive cell lines, we found that all three cell lines showed tube formation on Matrigel in the presence of angiogenic growth factors including EGF, FGF2, IGF1, or VEGF. Clinically, VM channels significantly increased in surviving cancer cell clusters of surgically removed tumors pretreated with trastuzumab and chemotherapy compared to both surgically removed tumors without prior systemic treatment and tumors biopsied before presurgical treatment with trastuzumab. Finally, we found that salinomycin completely suppressed VM in all three trastuzumab-resistant cell lines through disruption of actin cytoskeletal integrity.

Conclusions

VM promotes metastasis and worsens patient outcomes. The present study indicates that HER2-positive BCCs can exhibit VM in an angiogenic microenvironment after eventually acquiring trastuzumab resistance. The clinical finding supports this in vitro observation. Thus, targeting VM might provide a therapeutic benefit to patients with HER2-positive breast cancer.

Electronic supplementary material

The online version of this article (10.1186/s13058-019-1167-3) contains supplementary material, which is available to authorized users.

Prognostic value of tumor cell DNA content determined by flow cytometry using formalin-fixed paraffin-embedded breast cancer tissues

PURPOSE

The use of formalin-fixed paraffin-embedded (FFPE) tumor tissues in flow cytometry (FCM)-based determination of tumor cell DNA content is more complicated than the use of fresh-frozen tissues. This study aimed to accurately measure tumor cell DNA content from FFPE tissues by separating tumor cells from stromal cells through FCM and investigating its prognostic impact.

METHODS

We separately measured the DNA contents of tumor cells and stromal cells by gating with pan-cytokeratin and vimentin (FCM^C/V). We evaluated tumor cell DNA contents [DNA index (DI)] of 290 FFPE tumor tissues and classified them into low and high DI groups, using a cutoff DI value determined through an unbiased computational method.

RESULTS

The distribution of DI was bimodal, and a cutoff value was determined at a DI of 1.26. The high-DI tumors were associated with aggressive phenotypes and had significantly worse distant recurrence-free intervals (DRFI) than low-DI tumors. Multivariate analysis revealed that lymph node metastasis, Ki67, and DI were independent factors affecting DRFI. Accordingly, patients with low-DI/low-Ki67 tumors had excellent outcomes compared with other tumor types. Multiploid tumors were associated with increased lymphocytic infiltration and aggressive phenotypes.

CONCLUSIONS

The DI of FFPE tumors could be precisely determined through FCM^C/V. A combination of DI and Ki67 analyses may be able to predict the prognoses of breast cancer patients with greater accuracy.

Diagnostic Utility of Third-Look, Contrast-Enhanced Sonography Followed by Needle Biopsy for MRI, But Not Second-look Ultrasonography-detected Breast Lesions

BACKGROUND/AIM

To clarify the diagnostic utility of third-look, contrast-enhanced ultrasonography (CEUS) for MRI-detected breast lesions undetectable by unenhanced, second-look ultrasonography (MRI+/US- lesions).

PATIENTS AND METHODS

Clinical stage 0-IIA breast cancer patients who underwent CEUS for incidental MRI+/US- lesions (n=27; cohort 1) and patients with breast lesions detected only by MRI, to be examined by CEUS (n=15; cohort 2), were retrospectively analyzed.

RESULTS

Of the 42 MRI+/US- lesions, 23 (55%) were detected by CEUS and then examined by needle biopsy. Pathological examination showed that 10 of these 23 lesions were malignant. None of the 19 lesions undetected by CEUS were found to be histologically malignant or developed malignancy with a median follow-up of 18.5 months. The accuracy, sensitivity, and specificity of CEUS plus needle biopsy were 98%, 91%, and 100%, respectively.

CONCLUSION

Third-look CEUS followed by needle biopsy is useful in the initial diagnosis of MRI+/US- lesions.

Intraoperative Nomograms, Based on One-Step Nucleic Acid Amplification, for Prediction of Non-sentinel Node Metastasis and Four or More Axillary Node Metastases in Breast Cancer Patients with Sentinel Node Metastasis

Background

One-step nucleic acid amplification (OSNA) for cytokeratin 19 messenger RNA is an intraoperative diagnostic procedure for the detection of lymph node metastasis.

Objective

This study aimed to construct intraoperative nomograms using OSNA for the prediction of non-sentinel lymph node (NSLN) metastasis and four or more axillary lymph node (ALN) metastases.

Methods

Of the 4736 breast cancer patients (T1-3, N0) who underwent sentinel lymph node (SLN) biopsy and had SLNs examined intraoperatively with OSNA, 623 with SLN metastasis treated with completion ALN dissection (cALND) were retrospectively analyzed, and were randomly divided into training (n = 312) and validation (n = 311) sets.

Results

Of the clinicopathological parameters available preoperatively and intraoperatively, the multivariate analysis of the training set revealed that clinical tumor size and total tumor load (TTL) determined by OSNA were significantly associated with NSLN metastasis, and that clinical tumor size, number of macrometastatic SLNs, and TTL were significantly associated with four or more ALN metastases. Nomograms for NSLN metastasis and four or more ALN metastases were constructed using these parameters, and their area under the receiver operating characteristic curve (AUC) of the validation set were both 0.70, with a diagnostic accuracy similar to that of previously reported postoperative nomograms.

Conclusions

We constructed intraoperative nomograms using OSNA for the prediction of NSLN metastasis and four or more ALN metastases. These nomograms are as accurate as the conventional postoperative nomograms and might be helpful for decision making regarding the indication for cALND or the choice of adjuvant chemotherapeutic regimens and radiation field.

Electronic supplementary material

The online version of this article (10.1245/s10434-018-6633-0) contains supplementary material, which is available to authorized users.

Construction of a novel multi-gene assay (42-gene classifier) for prediction of late recurrence in ER-positive breast cancer patients

PURPOSE

Prediction models for late (> 5 years) recurrence in ER-positive breast cancer need to be developed for the accurate selection of patients for extended hormonal therapy. We attempted to develop such a prediction model focusing on the differences in gene expression between breast cancers with early and late recurrence.

METHODS

For the training set, 779 ER-positive breast cancers treated with tamoxifen alone for 5 years were selected from the databases (GSE6532, GSE12093, GSE17705, and GSE26971). For the validation set, 221 ER-positive breast cancers treated with adjuvant hormonal therapy for 5 years with or without chemotherapy at our hospital were included. Gene expression was assayed by DNA microarray analysis (Affymetrix U133 plus 2.0).

RESULTS

With the 42 genes differentially expressed in early and late recurrence breast cancers in the training set, a prediction model (42GC) for late recurrence was constructed. The patients classified by 42GC into the late recurrence-like group showed a significantly (P = 0.006) higher late recurrence rate as expected but a significantly (P = 1.62 × E-13) lower rate for early recurrence than non-late recurrence-like group. These observations were confirmed for the validation set, i.e., P = 0.020 for late recurrence and P = 5.70 × E-5 for early recurrence.

CONCLUSION

We developed a unique prediction model (42GC) for late recurrence by focusing on the biological differences between breast cancers with early and late recurrence. Interestingly, patients in the late recurrence-like group by 42GC were at low risk for early recurrence.

LATS2 promoter hypermethylation and its effect on gene expression in human breast cancer

Tumor-specific promoter hypermethylation of large tumor suppressor, homolog 2 (LATS2), a tumor suppressor gene, has been investigated using methylation-specific polymerase chain reaction (MSP) assays in different types of human cancer producing conflicting results. The aim of the present study was to evaluate the methylation status of the LATS2 promoter region using bisulfite sequencing with a next generation sequencer for breast cancer. In the 11 patients enrolled in the present study, the LATS2 promoter methylation index (MI) was uniformly high in tumor and normal tissues of the breast (median, 84.0 and 87.4%, respectively). The presence of LATS2 promoter hypermethylation was confirmed in isolated tumor cells and normal epithelial cells using the magnetic-activated cell sorting method. In situ hybridization for LATS2 messenger RNA (mRNA) revealed that the mRNA expression of LATS2 was higher in normal epithelial cells, compared with tumor cells, however, it was not significantly associated with LATS2 MI. In 12 breast cancer cell (BCC) lines and two normal breast cell lines, the LATS2 promoter was uniformly hypermethylated with no correlation between the mRNA expression of LATS2 and the LATS2 MI. In addition, treatment of the BCC lines with a demethylating reagent had minimal effect on the mRNA expression of LATS2 in any of these cell lines. These results demonstrated that LATS2 hypermethylation was not involved in silencing the mRNA expression of LATS2 mRNA. The lower mRNA expression level of LATS2 in tumor cells, compared with normal epithelial cells, suggested the possible involvement of downregulation in the mRNA expression of LATS2 in the pathogenesis of breast cancer. Therefore, the conflicting results previously reported for LATS2 promoter methylation in different types of cancer, detected using MSP assays may be attributable to the low fidelity of the MSP assay.

Endocrine sensitivity of estrogen receptor-positive breast cancer is negatively correlated with aspartate-β-hydroxylase expression

Although prognostic markers for early estrogen receptor (ER)‐positive breast cancer have been extensively developed, predictive markers for adjuvant endocrine therapy are still lacking. Focusing on the mechanisms underlying endocrine resistance, we investigated whether the endocrine sensitivity of ER‐positive breast cancer cells was correlated with the expression of aspartate‐β‐hydroxylase (ASPH), which is involved in the development of hepatocellular carcinoma. ASPH expression in ER‐positive and tamoxifen‐resistant breast cancer cells was upregulated by the MAPK and phosphoinositide‐3 kinase (PI3K) pathways, which both play pivotal roles in endocrine resistance. In the clinical setting, ASPH expression was negatively correlated with recurrence‐free survival of luminal B breast cancer patients that received adjuvant endocrine therapy, but not in patients that did not receive adjuvant endocrine therapy. Luminal B breast cancer is one of the intrinsic molecular subtypes identified by the Prediction Analysis of Microarray 50 (PAM50) multiple gene classifier, and because of its poor response to endocrine therapy, chemotherapy in addition to endocrine therapy is generally required after surgical resection. Our results suggest that the endocrine sensitivity of luminal B breast cancer can be assessed by examining ASPH expression, which promotes the consideration of a prospective study on the association between ASPH expression at the mRNA and protein levels in luminal B breast cancer and subsequent response to endocrine therapy.

Highly sensitive detection of ESR1 mutations in cell-free DNA from patients with metastatic breast cancer using molecular barcode sequencing

PURPOSE

We aimed to develop a highly sensitive method to detect ESR1 mutations in cell-free DNA (cfDNA) using next-generation sequencing with molecular barcode (MB-NGS) targeting the hotspot segment (c.1600-1713).

METHODS

The sensitivity of MB-NGS was tested using serially diluted ESR1 mutant DNA and then cfDNA samples from 34 patients with metastatic breast cancer were analyzed with MB-NGS. The results of MB-NGS were validated in comparison with conventional NGS and droplet digital PCR (ddPCR).

RESULTS

MB-NGS showed a higher sensitivity (0.1%) than NGS without barcode (1%) by reducing background errors. Of the cfDNA samples from 34 patients with metastatic breast cancer, NGS without barcode revealed seven mutations in six patients (17.6%) and MB-NGS revealed six additional mutations including three mutations not reported in the COSMIC database of breast cancer, resulting in total 13 ESR1 mutations in ten patients (29.4%). Regarding the three hotspot mutations, all the patients with mutations detected by MB-NGS had identical mutations detected by droplet digital PCR (ddPCR), and mutant allele frequency correlated very well between both (r = 0.850, p < 0.01). Moreover, all the patients without these mutations by MB-NGS were found to have no mutations by ddPCR.

CONCLUSION

In conclusion, MB-NGS could successfully detect ESR1 mutations in cfDNA with a higher sensitivity of 0.1% than conventional NGS and was considered as clinically useful as ddPCR.

Identification of sentinel lymph nodes by contrast-enhanced ultrasonography with Sonazoid in patients with breast cancer: a feasibility study in three hospitals

The aim of this prospective study was to evaluate the feasibility of periareolar injection of the contrast agent Sonazoid (SNZ) followed by ultrasonography (US) for the identification of sentinel lymph node (SLN) in breast cancer patients with clinically negative node. Patients (n = 100) with T1-2N0M0 breast cancer received a periareolar injection of SNZ followed by US to identify contrast-enhanced SLN. Each contrast-enhanced SLN underwent fine needle aspiration cytology (FNAC) followed by SLN biopsy with a conventional method using blue dye and/or radiocolloid (B/R). In almost all cases, contrast-enhanced lymphatic vessels were clearly visualized by US soon after the periareolar injection of SNZ and the SLNs were easily identified with an identification rate of 98% (98/100) for SNZ and 100% (100/100) for B/R. The number of SLNs identified by SNZ (SNZ-SLN) (mean per patient, 1.52) was significantly lower than that identified by B/R (B/R-SLN) (2.19) (P < 0.0001). Twenty-five patients with positive SLNs had at least one positive SNZ-SLN. On a node-by-node basis, sensitivity, specificity, and accuracy of FNAC for SNZ-SLNs (n = 149) were 33.3%, 99.2%, and 85.9%, respectively. Identification of SLN by periareolar injection of SNZ is a technically simple method with an identification rate as high as 98%. SNZ-SLN thus seems to be a good target for FNAC, but sensitivity of FNAC for SNZ-SLNs needs to be improved.

Abstract P2-01-27: Sentinel lymph node biopsy by contrast-enhanced ultrasonography with sonazoid in patients with breast cancer - Prospective multicenter study

Background: The aim of this prospective study is to evaluate feasibility of the periareolar injection of contrast agent (Sonazoid (SNZ)) followed by ultrasonography (US) for identification of sentinel lymph node (SLN) in breast cancer patients with clinically negative node.

Patients and Methods: Patients with T1-2N0M0 breast cancer were recruited in this study. They received the periareolar injection of SNZ followed by US to identify contrast-enhanced SLN. Fine needle aspiration biopsy (FNAB) was done for each CE-SLN. Then, they underwent SLN biopsy with the conventional method, blue dye and/or radiotracer (B/R).

Results: In almost all cases, contrast-enhanced lymphatic vessels were clearly visualized US soon after the periareolar injection of SNZ, and SLN, into which lymphatic flow was draining, was easily identified. The identification rate of SLN was 98% (98/100) by SNZ and 100% (100/100) by B/R. The number of SLNs identified by SNZ (mean per patient, 1.52) was significantly (P &lt; 0.001) lower than that of those by B/R (2.22). Twenty-five patients had at least one metastasis in the SLNs identified by SNZ and/or B/R. In these patients, SLNs (n=39) identified by both SNZ and B/R showed a significantly (P &lt; 0.0001) higher positivity (74.4%) for metastases than those (n=19) identified by B/R alone (21.1%).

Conclusion: Identification of SLN by periareolar injection of SNZ followed by US is a technically easy method and the identification rate of SLN was as high as 98%, being comparable to the conventional B/R. SLNs detected by SNZ seem to represent the true SLNs which first receive lymphatic flow from the tumor among the SLNs detected by B/R.

Citation Format: Shimazu K, Ito T, Uji K, Miyake T, Motomura K, Noguchi S. Sentinel lymph node biopsy by contrast-enhanced ultrasonography with sonazoid in patients with breast cancer - Prospective multicenter study [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P2-01-27.