A progressive and refractory case of breast cancer with Cowden syndrome.

BACKGROUND: Cowden syndrome is a rare autosomal-dominant disease with a high risk of malignant tumors of the breast, commonly caused by germline mutations in the PTEN gene. Most breast cancers related to Cowden syndrome showed typically a slow-growing and favorable clinical course. Here, we report a progressive case of triple-negative breast cancer in a patient who was diagnosed with Cowden syndrome. CASE PRESENTATION: A 35-year-old female with breast cancer was referred to our hospital. Histopathological examination of the tumor showed that it was triple-negative breast cancer with high proliferation marker. Preoperative positron emission tomography-computed tomography showed abnormal uptake in the left cerebellar hemisphere in addition to the right breast and axillary lymph node. Brain T2-weighted magnetic resonance imaging revealed hyperintense bands in the left cerebellar hemisphere lesion, which demonstrated a "tiger-stripe" appearance. The patient's mother had died of endometrial cancer. Subsequently, she underwent genetic testing, leading to a diagnosis of Cowden syndrome with a pathogenic variant c.823_840del.18 at exon 8 in PTEN. She was treated with neoadjuvant chemotherapy of eribulin and cyclophosphamide followed by adriamycin and cyclophosphamide. However, her tumors increased after these treatments. She was immediately surgically treated and received adjuvant chemotherapy of capecitabine. Unfortunately, the cancer recurred in the lung nine months after surgery. We then administered paclitaxel and bevacizumab therapy, but the disease rapidly progressed. Consequently, the patient died due to breast cancer about three months after recurrence. CONCLUSION: We report an aggressive case of cancer with Cowden syndrome which was resistant to standard chemotherapy. Alteration of the phosphatidylinositol-3 kinase/Akt/mammalian target of rapamycin pathway due to inactivating PTEN protein may be associated with chemoresistance and serves as a candidate for therapeutic intervention in PTEN-related cancers.

Cardiac computed tomography-derived myocardial tissue characterization after anthracycline treatment.

AIMS: Understanding cardiac function after anthracycline administration is very important from the perspective of preventing the onset of heart failure. Although cardiac magnetic resonance and echocardiography are recognized as the 'gold standard' for detecting cardiotoxicity, they have many shortcomings. We aimed to investigate whether cardiac computed tomography (CCT) could replace these techniques, assessing serial changes in cardiac tissue characteristics as determined by CCT after anthracycline administration. METHODS AND RESULTS: We prospectively investigated 15 consecutive breast cancer patients who were scheduled to receive anthracycline therapy. We performed echocardiography and CCT before and 3, 6, and 12 months after anthracycline treatment. The mean cumulative administered anthracycline dose was 269.9 ± 14.6 mg/m2 (doxorubicin-converted dose). Of the 15 enrolled patients who received anthracycline treatment for breast cancer, none met the definition of cardiotoxicity. The CCT-derived extracellular volume fraction tended to continue to increase after anthracycline treatment and had relatively similar dynamics to the left ventricular ejection fraction and global longitudinal strain as determined by echocardiography. CONCLUSIONS: Our findings indicated that CCT could provide adequate information about the characteristics of myocardial tissue after anthracycline administration. CCT may improve the understanding of cardiotoxicity by compensating for the weaknesses of echocardiography. This technique could be useful for understanding cardiac tissue characterization as a 'one-stop shop' evaluation, providing new insight into cardiooncology.

Predictive and prognostic significance of BRCAness in HER2-negative breast cancer.

BACKGROUND: BRCAness is characterized as the phenotypes shared between some sporadic tumors and BRCA1/2 mutation cancers resulting in defective homologous recombination. The predictive or prognostic value of BRCAness in HER2-negative breast cancer patients who have received neoadjuvant chemotherapy (NAC) is not fully elucidated. METHODS: We retrospectively selected 101 high-risk HER2-negative patients diagnosed with stage I-III breast cancer who underwent NAC treatment and evaluated BRCA1-like phenotype using multiplex ligation-dependent probe amplification assay. In an analysis of BRCAness, 95 out of 101 patients were analyzed. RESULTS: In total, 70 (74%) patients had sporadic-type tumors and 25 (26%) had BRCA1-like tumors according to pre-treatment samples. The BRCA1-like phenotype was not associated with pathological complete response (pCR) rate in the entire cohort. In survival analysis, pre-treatment BRCA1-like phenotype was not associated with survival. On the other hand, post-treatment BRCA1-like patients apparently showed shorter relapse-free survival (log-rank P = 0.016) and breast cancer-specific survival (P < 0.001) compared with sporadic features. In multivariate analysis, only the post-treatment BRCA1-phenotype was significant prognostic factors (HR 5.67, 95% CI 1.19-29.3). Furthermore, we found phenotype change between BRCA1-like and sporadic type through NAC in 19% of non-pCR patients. Post-treatment Ki67 significantly decreased in the persistent sporadic tumors during treatment or sporadic tumors changed after NAC (P < 0.0001, P = 0.0078, respectively). CONCLUSIONS: BRCAness may be useful biomarkers to predict prognosis for HER2-negative breast cancer refractory to standard chemotherapy. Our results pave the way for identifying patients who require alternative therapies.

Exosomal miRNA profiles of triple-negative breast cancer in neoadjuvant treatment.

Triple-negative breast cancer (TNBC) is characterized by aggressive clinicopathological features and is associated with a poor prognosis. Identifying patients that are non-responsive to chemotherapy remains a critical goal for effective personalized therapies. In the present study, the predictive value of exosomal microRNAs (miRNAs) was investigated in patients with TNBC. Exosomes were isolated from patients with TNBC undergoing neoadjuvant chemotherapy. Microarray-based miRNA profiles were compared between patients with pathological complete response (pCR; n=12) and non-pCR (n=12). Furthermore, the miRNA profiles of non-pCR patients with breast cancer recurrence were compared with those with no recurrence. A total of 16 differentially expressed exosomal miRNAs were identified between the patients with pCR and non-pCR by microarray analysis. Of these, a combined signature of four miRNAs (miR-4448, miR-2392, miR-2467-3p and miR-4800-3p) could be used to discriminate between pCR and non-pCR patients with TNBC with an area under the curve value of 0.7652. Furthermore, this study found 43 differentially expressed miRNAs between the patients with non-pCR and recurrence and non-pCR patients without recurrence. In network analysis, 'pathway in cancer', 'focal adhesion' and 'cell cycle' were identified as the crucial pathways in patients with non-pCR who also developed recurrence. Several exosomal miRNAs may be useful biomarkers to predict treatment efficacy for TNBC. The present study identified patients who were resistant to standard chemotherapy and therefore more likely to develop breast cancer recurrence.

Cardiac computed tomography-derived extracellular volume fraction in late anthracycline-induced cardiotoxicity.

Cardiotoxicity in the late phase after anthracycline drugs administration remains to be defined. Of the 44 patients who received anthracycline treatment, 7 were found to have cancer therapeutics-related cardiac dysfunction (CTRCD). The global longitudinal strain determined by echocardiography and myocardial extracellular volume fraction (ECV) determined by cardiac computed tomography (CCT) of the CTRCD(+) group were significantly higher than those of the control group and CTRCD(-) group, whereas there were no significant differences between the control and CTRCD(-) groups. Our findings indicated that CCT may be a tool comparable to echocardiography, indicating the effective evaluation of CTRCD by CCT.

Analysis of plasma HER2 copy number in cell-free DNA of breast cancer patients: a comparison with HER2 extracellular domain protein level in serum.

BACKGROUND: HER2 (human epidermal growth factor receptor 2) status has been evaluated in breast cancer (BC) tissues by immunohistochemistry or in situ hybridization. We evaluated HER2 copy number (CN) assay in plasma cell-free DNA (cfDNA) from blood samples and compared it with protein measurements of HER2 extracellular domain (ECD) in serum. METHODS: Serum HER2-ECD levels were measured by chemi-luminescence immunoassay using anti-HER2 monoclonal antibodies. Analyses were performed on 120 cases of primary BC, 30 cases of metastatic BC and 34 cases treated by neoadjuvant chemotherapy (NAC). This study was approved by Medical Research Review Advancement No. 1857 for Kumamoto University. RESULTS: There was a positive correlation between HER2-CN ratios and HER2-ECD levels, in primary (n = 54) and metastatic (n = 30) HER2-positive BC (P = 0.003 and P < 0.001, respectively). HER2-ECD levels were significantly higher in patients with a larger number of metastatic sites (P = 0.02). The usefulness of HER2 levels in discriminating primary and metastatic HER2-positive BC evaluated by ROC curve analysis was better in the HER2-ECD assay than in the HER2-CN assay. In 34 patients who received NAC, there was a small decrease in HER2-CN ratios between before and after NAC (P = 0.10), while there was an obvious decrease in HER2-ECD levels between before and after NAC (P < 0.001). CONCLUSION: Compared to HER2-ECD levels, the clinical usefulness of HER2-CN ratio was somewhat inferior. Improved measurement methods and further examination of the association with long-term prognosis and the response to anti-HER2 treatment analyzed by HER2-CN and HER2-ECD assay are required.

The role of exosomal microRNAs; focus on clinical applications in breast cancer.

Despite several advances in targeted therapies for breast cancer, breast-cancer-associated death remains high in women. This is partially due to the lack of reliable markers predicting metastatic disease or recurrence after initial therapy. Recent research into the clinical validity of circulating cancer-specific biomarkers as a "liquid biopsy" is of growing interest. Of these, exosomal microRNAs (miRNAs) are promising candidate biomarkers for clinical use in breast cancer. In addition to their diagnostic value, exosomal miRNAs play an important role in predicting clinical outcome or treatment response. In this review, it is focused on the findings concerning exosomal miRNAs in relation to disease detection, prognostic impact and therapeutic effect in breast cancer, and discuss their clinical utility.

APOBEC3B gene expression as a novel predictive factor for pathological complete response to neoadjuvant chemotherapy in breast cancer.

BACKGROUND: Apolipoprotein B mRNA editing enzyme catalytic polypeptide-like 3B (APOBEC3B) is a gene editing enzyme with cytidine deaminase activity and high expression of its mRNA in breast tumors have been shown to be associated with progressive cases and poor prognosis. In this study, we aimed to examine the relationship between the expression of APOBEC3B and the effect of neoadjuvant chemotherapy (NAC) using pretreatment biopsy tissue, and examined whether the expression of APOBEC3B influenced chemotherapy efficacy. METHODS: We retrospectively selected a total of 274 patients with primary breast cancer who received NAC in more than 4 courses and underwent surgery at our institute. We assessed the expression of APOBEC3B mRNA using pretreatment biopsy specimens of NAC by quantitative real-time PCR (qRT-PCR) and examined the relationship between APOBEC3B mRNA expression and sensitivity to chemotherapy using pathological complete response (pCR) as an indicator. Further, we assessed the prognostic value of APOBEC3B in the patients receiving NAC. RESULTS: APOBEC3B mRNA expression levels were successfully assessed in 173 (63.1%) of the 274 specimens. The total pCR rate was 36.4% (n = 63). An association between APOBEC3B expression levels and pCR was observed (Wilcoxon test, P ≤ 0.0001). The patients were divided into two groups, low (n = 66) and high (n = 107), according to the APOBEC3B expression levels, using the cut-off value calculated by the receiver operating characteristics (ROC) curve for pCR. The rate of pCR was significantly higher among the patients in the high group than among those in the low group (47.7% vs 18.2%, P ≤ 0.0001). High APOBEC3B expression was significantly associated with high nuclear grade (P = 0.0078), high Ki-67 labeling index (P = 0.0087), estrogen receptor (ER) negativity (P ≤ 0.0001) and human epidermal growth factor receptor 2 (HER2) negativity (P = 0.032). Tumor size (P = 0.011), ER (P ≤ 0.0001), HER2 (P = 0.0013) and APOBEC3B expression (P = 0.037) were independent predictive factors for pCR in multivariate analysis. However, there was no association between APOBEC3B expression and prognosis. CONCLUSIONS: Our study showed that APOBEC3B mRNA expression correlated with sensitivity to NAC in breast cancer patients. In contrast to previous studies, APOBEC3B mRNA expression was not associated with breast cancer prognosis in patients receiving NAC.

Therapeutic predictors of neoadjuvant endocrine therapy response in estrogen receptor-positive breast cancer with reference to optimal gene expression profiling.

PURPOSE: Neoadjuvant endocrine therapy (NAET) for estrogen receptor-positive primary breast cancer causes adequate tumor shrinkage, and is expected to be helpful for breast-conserving surgery, but the adaptation criteria, especially in regard to treatment duration, have never been elucidated. Re-visiting past gene expression profiles, we explored the data for specialized pre-therapeutic predictors and validated the results using our in-house clinical cohorts. METHODS: We sorted the genes related to a > 30% tumor volume reduction through NAET from a cDNA microarray data-set of GSE20181, then selected the top 40 genes. We validated these gene expression levels using pre-therapeutic biopsy samples obtained from patients treated with long-term NAET (over 4 months; N = 40). A short-term (2-8 weeks; N = 37) NAET cohort was also validated to clarify whether expression of these genes is also related to a rapid response of Ki67 and PEPI score. RESULTS: In the long-term group, higher expression of KRAS, CUL2, FAM13A, ADCK2, and LILRA2 was significantly associated with tumor shrinkage, and KRAS, MMS19, and IVD were related to lower PEPI score (≤ 3). Meanwhile in the short-term group, none of these genes except CUL2 showed a direct correlation with Ki67 reduction or PEPI score. This suggested that tumor shrinkage by NAET might be induced by response to the hypoxic environment (CUL2, FAM13A, KRAS) and activation of tumor immune system (LILRA2), without involving inhibition of proliferation. CONCLUSION: Expression of specific genes may allow selection of the most responsive patients for maximum tumor shrinkage with NAET.

ESR1 and PIK3CA mutational status in serum and plasma from metastatic breast cancer patients: A comparative study.

PURPOSE: Plasma and serum cell-free DNA (cfDNA) are useful sources of tumor DNA, but comparative investigations of the tumor mutational status between them are rare. METHODS: we performed droplet digital PCR assay for representative hotspot mutations in metastatic breast cancer (MBC) (ESR1 and PIK3CA) in serum and plasma cfDNA concurrently extracted from the blood of 33 estrogen receptor-positive MBC patients. RESULTS: ESR1 mutations in plasma cfDNA were found in 7 of the 33 patients; ESR1 mutations in serum cfDNA were detected in only one out of 7 patients with ESR1 mutations in plasma cfDNA. PIK3CA exon 9 and exon 20 mutations in plasma cfDNA were found in 3 and 7 out of the 33 patients, respectively; PIK3CA exon 9 mutations in serum cfDNA were detected in 2 out of 3 patients with PIK3CA exon 9 mutations in plasma cfDNA; PIK3CA exon 20 mutations in serum cfDNA were detected in 2 out of 7 patients with PIK3CA exon 20 mutations in plasma cfDNA. CONCLUSIONS: Here we show the higher frequency of ESR1 and PIK3CA mutations in the plasma than in the serum in 33 MBC patients; therefore, serum samples should not be considered the preferred source of cfDNA.

Clinical significance of plasma cell-free DNA mutations in PIK3CA, AKT1, and ESR1 gene according to treatment lines in ER-positive breast cancer.

The somatic activation of PI3K/AKT pathway mutations, PIK3CA and AKT1, and ESR1 mutations in plasma cell-free DNA (cfDNA) has been studied as a non-invasive procedure to quickly assess and monitor disease progression or therapeutic effect in breast cancer (BC) patients, but the clinical significance of these mutations in late treatment lines (TLs) remains unclear. The subjects of this study were a total of 251 plasma samples from 128 estrogen receptor-positive (ER+) BC patients. Of these plasma samples, 133 were from 73 primary BC (PBC) patients, and 118 plasma samples were from 68 metastatic BC (MBC) patients. We developed droplet digital PCR (ddPCR) assays to verify the clinical significance of PIK3CA, AKT1, and ESR1 mutations in these patients. cfDNA PIK3CA mutations were observed in 15.1% of the PBC patients, while a cfDNA AKT1 mutation was observed in 1.4% of patients, and cfDNA ESR1 mutations were observed in 2.7% of patients. Patients with detectable cfDNA PIK3CA mutations were not associated with clinical outcomes. According to the TL, the prevalence of the PIK3CA and ESR1 mutations in cfDNA were lower in early TLs compared with late TLs. In the early TL group, patients with cfDNA PIK3CA mutations had a shorter time to treatment failure (TTF) than patients without mutations (P = 0.035). However, there was no statistically significant difference between patients with or without cfDNA ESR1 mutations. However, in the late TL group, patients with cfDNA ESR1 mutations had a shorter TTF than patients without mutations (P = 0.048). However, there was no statistically significant difference between patients with or without cfDNA PIK3CA mutations. Since the prevalence of cfDNA AKT1 mutation is low in both PBC and MBC patients, the impact of AKT1 mutations on the prognosis remains unclear. We have demonstrated the difference in the clinical significance of the hotspot PIK3CA, AKT1, and ESR1 mutations in cfDNA for each TL in ER+ BC patients.

Factors involved in early lenvatinib dose reduction: a retrospective analysis.

Lenvatinib, a multi-tyrosine kinase inhibitor, has been proven to be an effective treatment option for patients with iodine-131-refractory thyroid cancer. Many adverse effects of lenvatinib have been reported; thus, dose reduction is common. However, a few studies have analyzed the causes of lenvatinib dose reduction in daily clinical practice. Here, we investigate the factors involved in early lenvatinib dose reduction to analyze lenvatinib dose modification. We analyzed 20 thyroid cancer patients who began receiving lenvatinib at the Kumamoto University Hospital Cancer Center from July 2015 to November 2016. Patients were classified into the following groups based on the time until first withdrawal or dose reduction in lenvatinib: group A (early, ≤ 10 days) and group B (other, > 10 days). Patients' clinical features and reasons for withdrawal or dose reduction were analyzed. The age range of patients was 54-91 years, and the median observation period was 293 days. There were no significant differences in the administered line of lenvatinib; the presence/absence of primary residual tumors; or the history of hypertension, proteinuria, and diarrhea between the two groups (A, n = 7; B, n = 13). The cause for initial withdrawal or dose reduction was grade 3 hypertension in all group A patients, which was significantly higher than that in group B (p = 0.0001). Our results suggest that early blood pressure control may be effective as a method to maintain the lenvatinib dose intensity.

Prevalence of ESR1 E380Q mutation in tumor tissue and plasma from Japanese breast cancer patients.

BACKGROUND: ESR1 mutations have attracted attention as a potentially important marker and treatment target in endocrine therapy-resistant breast cancer patients. The E380Q mutation, which is one of the ESR1 mutations, is associated with estradiol (E2) hypersensitivity, increased DNA binding to the estrogen response element, and E2-independent constitutive trans-activation activity, but its frequency in ESR1 mutations remains unknown. The present study aimed to investigate the E380Q mutation in comparison with the other representative ESR1 mutations. METHODS: We screened a total of 62 patients (66 tumor tissues and 69 plasma cell-free DNA (cfDNA)) to detect ESR1 mutations (E380Q, Y537S, Y537N, Y537C, and D538G) using droplet-digital polymerase chain reaction. Plasma was collected at more than two points of the clinical course, in whom changes of ESR1 mutations under treatment were investigated. RESULTS: We detected ESR1 mutations in 21% (12/57) of MBCs. The E380Q ESR1 mutation was found in 16% (2/12) and the other ESR1 LBD mutations were five (41.6%) of Y537S, and four each (33.3%) of D538G, Y537N, and Y537C, in 12 ESR1 mutant breast cancer patients. Five tumors had multiple ESR1 mutations: three had double ESR1 mutations; Y537S/E380Q, Y37S/Y537C, and Y537S/D538G, and two had triple ESR1 mutations; Y537S/Y537N/D538G. In plasma cfDNA analysis, the E380Q mutation was not detected, but increases in other ESR1 mutations were detected in 46.2% (6/13) of MBC patients under treatment. CONCLUSIONS: We have shown that there are distinct populations of ESR1 mutations in metastatic tissue and plasma. Each ESR1 mutation may have different clinical significance, and it will be necessary to investigate them all.

Genetic and environmental factors and serum hormones, and risk of estrogen receptor-positive breast cancer in pre- and postmenopausal Japanese women.

Breast cancer incidence in Japanese women has more than tripled over the past two decades. We have previously shown that this marked increase is mostly due to an increase in the estrogen receptor (ER)-positive, HER2-negative subtype. We conducted a case-control study; ER-positive, HER2-negative breast cancer patients who were diagnosed since 2011 and women without disease were recruited. Environmental factors, serum levels of testosterone and 25-hydroxyvitamin D, and common genetic variants reported as predictors of ER-positive breast cancer or found in Asian women were evaluated between patients and controls in pre- and postmenopausal women. To identify important risk predictors, risk prediction models were created by logistic regression models. In premenopausal women, two environmental factors (history of breastfeeding, and history of benign breast disease) and four genetic variants (TOX3-rs3803662, ESR1-rs2046210, 8q24-rs13281615, and SLC4A7-rs4973768) were considered to be risk predictors, whereas three environmental factors (body mass index, history of breastfeeding, and hyperlipidemia), serum levels of testosterone and 25-hydroxyvitamin D, and two genetic variants (TOX3-rs3803662 and ESR1-rs2046210) were identified as risk predictors. Inclusion of common genetic variants and serum hormone measurements as well as environmental factors improved risk assessment models. The decline in the birthrate according to recent changes of lifestyle might be the main cause of the recent notable increase in the incidence of ER-positive breast cancer in Japanese women.

Differential expression of exosomal miRNAs between breast cancer patients with and without recurrence.

BACKGROUND: Exosomal microRNAs (miRNAs) are promising candidate biomarkers for diagnosis or prognosis for breast cancer. We investigated the prognostic role of exosomal miRNAs in serum samples derived from patients with breast cancer and compared miRNA expression between serum and tumor tissues. METHODS: The miRNA profile derived from exosome between breast cancer patients with recurrence (n = 16) and without recurrence (n = 16) were compared by miRNA PCR array. Further, we examined the expression of miRNAs derived from tissues in the patients with breast cancer with (n = 35) and without recurrence (n = 39) by qRT-PCR. RESULTS: Of 384 miRNAs, three miRNAs (miR-338-3p, miR-340-5p, and miR-124-3p) were significantly upregulated and eight (miR-29b-3p, miR-20b-5p, miR-17-5p, miR-130a-3p, miR-18a-5p, miR-195-5p, miR-486-5p, and miR-93-5p) were significantly downregulated in the patients with recurrence. We evaluated the expression of the miRNAs in tumor tissues. The patients with recurrence had higher levels of miR-340 at their primary site as well as in the serum. In contrast, miR-195-5p, miR-17-5p, miR-93-5p, and miR-130a-3p, derived from tumor tissues that were downregulated in the serum from patients with recurrence, were higher in the patients with recurrence than in those with no recurrence. In logistic regression analysis, miR-340-5p, miR-17-5p, miR-130a-3p, and miR-93-5p were significantly associated with recurrence. CONCLUSIONS: Several exosomal miRNAs may be useful biomarkers to predict breast cancer recurrence. We show the different expression patterns of miRNAs between tumor tissues and serum. These findings may suggest selective mechanism of release of exosomal miRNAs by cancer cells to regulate their progression.

Analysis of ESR1 and PIK3CA mutations in plasma cell-free DNA from ER-positive breast cancer patients.

BACKGROUND: The measurement of ESR1 and PIK3CA mutations in plasma cell-free DNA (cfDNA) has been studied as a non-invasive method to quickly assess and monitor endocrine therapy (ET) resistant metastatic breast cancer (MBC) patients. METHODS: The subjects of this retrospective study were a total of 185 plasma samples from 86 estrogen receptor-positive BC patients, of which 151 plasma samples were from 69 MBC patients and 34 plasma samples were from 17 primary BC (PBC) patients. We developed multiplex droplet digital PCR assays to verify the clinical significance of ESR1 and PIK3CA mutations both in a snapshot and serially in these patients. RESULTS: cfDNA ESR1 and PIK3CA mutations were found in 28.9% and 24.6 % of MBC patients, respectively. The relation between ESR1 or PIK3CA mutations and clinical features showed that ESR1 mutations occurred mostly in patients previously treated by ET, which was not the case for PIK3CA mutations. The analysis of the clinical impact of those mutations on subsequent lines of treatment for the 69 MBC patients revealed that both ESR1 and PIK3CA mutations detection were related to a shorter duration of ET effectiveness in univariate analysis but only for ESR1 mutations in multivariate analysis. The monitoring of cfDNA in a subset of 52 patients showed that loss of ESR1 mutations was related to a longer duration of response, which was not the case for PIK3CA mutations. CONCLUSIONS: We have demonstrated the clinical significance of on-treatment ESR1 mutations both in a snapshot and serially in comparison with PIK3CA mutations.

Comparison of ESR1 Mutations in Tumor Tissue and Matched Plasma Samples from Metastatic Breast Cancer Patients.

BACKGROUND: ESR1 mutation in circulating cell-free DNA (cfDNA) is emerging as a noninvasive biomarker of acquired resistance to endocrine therapy, but there is a paucity of data comparing the status of ESR1 gene in cfDNA with that in its corresponding tumor tissue. The objective of this study is to validate the degree of concordance of ESR1 mutations between plasma and tumor tissue. METHODS: ESR1 ligand-binding domain mutations Y537S, Y537N, Y537C, and D538G were analyzed using droplet digital PCR in 35 patients with metastatic breast cancer (MBC) (35 tumor tissue samples and 67 plasma samples). RESULTS: Of the 35 paired samples, 26 (74.3%) were concordant: one patient had detectable ESR1 mutations both plasma (ESR1 Y537S/Y537N) and tumor tissue (ESR1 Y537S/Y537C), and 25 had WT ESR1 alleles in both. Nine (25.7%) had discordance between the plasma and tissue results: five had mutations detected only in their tumor tissue (two Y537S, one Y537C, one D538G, and one Y537S/Y537N/D538G), and four had mutations detected only in their plasma (one Y537S, one Y537N, and two Y537S/Y537N/D538G). Furthermore, longitudinal plasma samples from 19 patients were used to assess changes in the presence of ESR1 mutations during treatment. Eleven patients had cfDNA ESR1 mutations over the course of treatment. A total of eight of 11 patients with MBC with cfDNA ESR1 mutations (72.7%) had the polyclonal mutations. CONCLUSION: We have shown the independent distribution of ESR1 mutations between plasma and tumor tissue in 35 patients with MBC.

Clinical features of lenvatinib treatment in elderly patients with advanced thyroid cancer.

Until recently, there had not been an effective systemic chemotherapy for advanced differentiated thyroid carcinoma (DTC); lenvatinib, a multi-tyrosine kinase inhibitor, has been proven effective for DTC, but has also been revealed to have adverse side effects including hypertension, hand-foot syndrome (HFS) and diarrhea. There have been few clinical studies focused on the characteristics, safety concerns or precautions for lenvatinib treatment in elderly patients. The present study administered lenvatinib to 18 patients with DTC in Kumamoto University Hospital (Kumamoto, Japan), with 9 patients in both the younger group (<75 years old) and elderly group (≥75 years old). The median maximum systolic blood pressure (sBP) was significantly different between the two groups (158 mmHg in the younger group vs. 173 mmHg in the elderly group; P=0.042). There were no significant differences in median maximum diastolic blood pressure (94 vs. 95 mmHg; P=1.00), median degree of sBP elevation (43 vs. 55 mmHg; P=0.199) or median days until hypertension diagnosis (2.11 vs. 2.33 days; P=0.436). There were also no significant differences in other toxicities (HFS, proteinuria or diarrhea). In conclusion, lenvatinib should be introduced carefully to elderly patients with DTC, as they tend to present with hypertension during treatment. However, there were no differences in other toxicities between the younger and elderly groups; lenvatinib was fully tolerated in patients with DTC >75 years old.

Lenvatinib, an oral multi-kinases inhibitor, -associated hypertension: Potential role of vascular endothelial dysfunction.

BACKGROUND AND AIMS: Lenvatinib (Lenvima®), an oral multi-kinase inhibitor, is effective in the treatment of differentiated thyroid carcinomas (DTCs). A severe adverse effect of lenvatinib is hypertension, thus limiting its use as an anti-cancer treatment. Although the pathogenesis of hypertension is generally assumed to involve microvascular bed reduction and an increase in peripheral vascular resistance due to a decrease in nitrogen oxide (NOx) production after vascular endothelial growth factor (VEGF) inhibition, the effects of hypertension on vascular endothelial function in actual patients remain unclear. Here, we examined how lenvatinib affects vascular endothelial function. METHODS: Ten consecutive DTC patients who did not take any cardiovascular agents were orally administered 24 mg of lenvatinib once daily. Using an EndoPAT2000® system, we used reactive hyperemia-peripheral arterial tonometry (RH-PAT) and evaluated vascular endothelial function on the basis of the RH-PAT index (RHI). We expressed the results as %RHI, which indicates the change compared with pretreatment levels. Additionally, we measured serum NOx and plasma VEGF concentrations pre- and post-treatment. RESULTS: All of the patients treated with lenvatinib exhibited significant hypertension; the %RHI levels were significantly decreased the day after treatment with lenvatinib. Furthermore, serum NOx and plasma VEGF concentrations were significantly decreased and increased, respectively, compared with pretreatment levels. These results indicate that hypertension induced by lenvatinib may be caused by a decrease in nitric oxide production, as a result of VEGF inhibition and impaired vascular endothelial function. CONCLUSIONS: We provide the first demonstration that lenvatinib causes hypertension via vascular endothelial dysfunction in human subjects.

Clinical significance of monitoring ESR1 mutations in circulating cell-free DNA in estrogen receptor positive breast cancer patients.

BACKGROUND: The measurement of circulating cell-free DNA (cfDNA) may transform the management of breast cancer patients. We aimed to investigate the clinical significance of sequential measurements of ESR1 mutations in primary breast cancer (PBC) and metastatic breast cancer (MBC) patients. RESULTS: ESR1 mutations ratio in the PBC groups was used as the minimum cutoff for determining increases in cfDNA ESR1 mutation ratio. An increase in cfDNA ESR1 mutations was found in 13 samples of cfDNA from 12 (28.6%) out of 42 MBC patients. A total of 10 (83.3%) out of 12 MBC patients with increase cfDNA ESR1 mutations showed a poor response to treatment. In survival analysis, increase cfDNA ESR1 mutations may predict a shorter duration of post-endocrine-therapy effectiveness (P = 0.0033). METHODS: A total of 119 patients (253 plasma samples) with breast carcinoma were enrolled in this study. Cases were selected if archival plasma samples were available from PBC before and after treatment and from MBC gathered more than twice at the time of progression. cfDNA was isolated from the 77 PBC patients (154 plasma samples) and from the 42 MBC patients (99 plasma samples). To investigate any changes in each cfDNA ESR1 mutation before and after treatment, we analyzed the difference with cfDNA ESR1 mutations ratio in the first blood sample using droplet digital polymerase chain reaction (ddPCR). CONCLUSIONS: We demonstrate that ddPCR monitoring of the recurrent ESR1 mutation in cfDNA of MBC patients is a feasible and useful method of providing relevant predictive information.