Masakazu Toi

Prof. Dr. Masakazu Toi

orcid

Research Focus & Metrics

Academic Career Length

25Years (2002-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 May 2021 in Journal of Clinical Oncology
Verified
Journal Article
Closed access
MPMartine Piccart
Martine Piccart
MPMarion Procter
Marion Procter
DFDebora Fumagalli
Debora Fumagalli
EAEvandro de Azambuja
Evandro de Azambuja
ECEmma Clark
Emma Clark
INInvestigators
Investigators
PURPOSE: APHINITY, at 45 months median follow-up, showed that pertuzumab added to adjuvant trastuzumab and chemotherapy significantly improved invasive disease–free survival (IDFS) (hazard ratio 0.81 [95% CI, 0.66 to 1.00], P = .045) for patients with early human epidermal growth factor receptor 2 (HER2)–positive breast cancer (BC), specifically those with node-positive or hormone receptor (HR)–negative disease. We now report the preplanned second interim overall survival (OS) and descriptive updated IDFS analysis with 74 months median follow-up. METHODS: After surgery and central HER2-positive confirmation, 4,805 patients with node-positive or high-risk node-negative BC were randomly assigned (1:1) to either 1-year pertuzumab or placebo added to standard adjuvant chemotherapy and 1-year trastuzumab. RESULTS: This interim OS analysis comparing pertuzumab versus placebo did not reach the P = .0012 level required for statistical significance ( P = .17, hazard ratio 0.85). Six-year OS were 95% versus 94% with 125 deaths (5.2%) versus 147 (6.1%), respectively. IDFS analysis based on 508 events (intent-to-treat population) showed a hazard ratio of 0.76 (95% CI, 0.64 to 0.91) and 6-year IDFS of 91% and 88% for pertuzumab and placebo groups, respectively. The node-positive cohort continues to derive clear IDFS benefit from pertuzumab (hazard ratio 0.72 [95% CI, 0.59 to 0.87]), 6-year IDFS being 88% and 83%, respectively. Benefit was not seen in the node-negative cohort. In a subset analysis, IDFS benefit from pertuzumab showed a hazard ratio of 0.73 (95% CI, 0.59 to 0.92) for HR-positive disease and a hazard ratio of 0.83 (95% CI, 0.63 to 1.10) for HR-negative disease. Primary cardiac events remain < 1% in both the treatment groups. No new safety signals were seen. CONCLUSION: This analysis confirms the IDFS benefit from adding pertuzumab to standard adjuvant therapy for patients with node-positive HER2-positive early BC. Longer follow-up is needed to fully assess OS benefit.

10 May 2021 in Journal of Clinical Oncology
Verified
Journal Article
Closed access
SLSibylle Loibl
Sibylle Loibl
FMFrederik Marmé
Frederik Marmé
MMMiguel Martin
Miguel Martin
MUMichael Untch
Michael Untch
HBHervé Bonnefoi
Hervé Bonnefoi
GMGunter von Minckwitz
Gunter von Minckwitz
PURPOSE: About one third of patients with hormone receptor–positive, human epidermal growth factor receptor 2–negative breast cancer who have residual invasive disease after neoadjuvant chemotherapy (NACT) will relapse. Thus, additional therapy is needed. Palbociclib is a cyclin-dependent kinase 4 and 6 inhibitor demonstrating efficacy in the metastatic setting. PATIENTS AND METHODS: PENELOPE-B ( NCT01864746 ) is a double-blind, placebo‐controlled, phase III study in women with hormone receptor–positive, human epidermal growth factor receptor 2–negative primary breast cancer without a pathological complete response after taxane‐containing NACT and at high risk of relapse (clinical pathological staging-estrogen receptor grading score ≥ 3 or 2 and ypN+). Patients were randomly assigned (1:1) to receive 13 cycles of palbociclib 125 mg once daily or placebo on days 1-21 in a 28-day cycle in addition to endocrine therapy (ET). Primary end point is invasive disease-free survival (iDFS). Final analysis was planned after 290 iDFS events with a two-sided efficacy boundary P < .0463 because of two interim analyses. RESULTS: One thousand two hundred fifty patients were randomly assigned. The median age was 49.0 years (range, 19-79), and the majority were ypN+ with Ki-67 ≤ 15%; 59.4% of patients had a clinical pathological staging-estrogen receptor grading score ≥ 3. 50.1% received aromatase inhibitor, and 33% of premenopausal women received a luteinizing hormone releasing hormone analog in addition to either tamoxifen or an aromatase inhibitor. After a median follow-up of 42.8 months (92% complete), 308 events were confirmed. Palbociclib did not improve iDFS versus placebo added to ET-stratified hazard ratio, 0.93 (95% repeated CI, 0.74 to 1.17) and two-sided weighted log-rank test (Cui, Hung, and Wang) P = .525. There was no difference among the subgroups. Most common related serious adverse events were infections and vascular disorders in 113 (9.1%) patients with no difference between the treatment arms. Eight fatal serious adverse events (two palbociclib and six placebo) were reported. CONCLUSION: Palbociclib for 1 year in addition to ET did not improve iDFS in women with residual invasive disease after NACT.

7 February 2017 in Scientific Reports
Verified
Journal Article
Open access
PDF file
MTMasakazu Toi
Masakazu Toi
YAY. Asao
Y. Asao
YMY. Matsumoto
Y. Matsumoto
HSH. Sekiguchi
H. Sekiguchi
AYA. Yoshikawa
A. Yoshikawa
TST. Shiina
T. Shiina
Noninvasive measurement of the distribution and oxygenation state of hemoglobin (Hb) inside the tissue is strongly required to analyze the tumor-associated vasculatures. We developed a photoacoustic imaging (PAI) system with a hemispherical-shaped detector array (HDA). Here, we show that PAI system with HDA revealed finer vasculature, more detailed blood-vessel branching structures, and more detailed morphological vessel characteristics compared with MRI by the use of breast shape deformation of MRI to PAI and their fused image. Morphologically abnormal peritumoral blood vessel features, including centripetal photoacoustic signals and disruption or narrowing of vessel signals, were observed and intratumoral signals were detected by PAI in breast cancer tissues as a result of the clinical study of 22 malignant cases. Interestingly, it was also possible to analyze anticancer treatment-driven changes in vascular morphological features and function, such as improvement of intratumoral blood perfusion and relevant changes in intravascular hemoglobin saturation of oxygen. This clinical study indicated that PAI appears to be a promising tool for noninvasive analysis of human blood vessels and may contribute to improve cancer diagnosis.

4 February 2022 in Clinical Cancer Research
Verified
Journal Article
Open access
PDF file
STSara M. Tolaney
Sara M. Tolaney
MTMasakazu Toi
Masakazu Toi
PNPatrick Neven
Patrick Neven
JSJoohyuk Sohn
Joohyuk Sohn
EGEva-Maria Grischke
Eva-Maria Grischke
GSGeorge W. Sledge
George W. Sledge
Purpose: PIK3CA and ESR1 mutations have been implicated in resistance to endocrine therapy (ET) in HR+, HER2− advanced breast cancer (ABC). Inhibition of CDK4 and 6 has been hypothesized as a therapeutic strategy to overcome endocrine resistance in patients with PIK3CA- or ESR1-mutant breast cancers. The objective of this exploratory analysis was to assess efficacy of abemaciclib plus fulvestrant in patients with or without PIK3CA or ESR1 mutations in MONARCH 2. Patients and Methods: MONARCH 2 was a global, randomized, double-blind phase III trial of abemaciclib plus fulvestrant in 669 women with HR+, HER2− ABC, which had progressed on ET. Patients were randomized 2:1 to receive abemaciclib plus fulvestrant or placebo plus fulvestrant. Exploratory analyses assessed progression-free survival (PFS) and overall survival (OS), and other endpoints, in patients with or without PIK3CA or ESR1 mutations detectable in baseline ctDNA. Results: From the MONARCH 2 population, 219 and 248 patient samples were successfully analyzed for either PIK3CA or ESR1 mutations, respectively. Abemaciclib plus fulvestrant improved PFS compared with placebo plus fulvestrant in both PIK3CA-wild-type (median 16.9 months vs. 12.3 months; HR, 0.51; 95% CI, 0.33–0.78) and PIK3CA-mutant subgroups (median 17.1 months vs. 5.7 months; HR, 0.53; 95% CI, 0.33–0.84), as well as both ESR1-wild-type (median 15.3 months vs. 11.2 months; HR, 0.44; 95% CI, 0.27–0.71) and ESR1-mutant subgroups (median 20.7 months vs. 13.1 months; HR, 0.54; 95% CI, 5.7–16.9). Additional endpoints, including OS, were also improved following treatment with abemaciclib plus fulvestrant regardless of PIK3CA or ESR1 mutation status. Conclusions: Abemaciclib plus fulvestrant was effective regardless of PIK3CA or ESR1 mutation status, with benefit in both PFS and OS, with a numerically greater improvement in median PFS relative to placebo plus fulvestrant for PIK3CA- or ESR1-mutant tumors compared with the respective wild-type subgroups, in women with HR+, HER2− ABC that had progressed on ET.

8 October 2018 in Scientific Reports
Verified
Journal Article
Open access
PDF file
YMYoshiaki Matsumoto
Yoshiaki Matsumoto
YAYasufumi Asao
Yasufumi Asao
HSHiroyuki Sekiguchi
Hiroyuki Sekiguchi
AYAya Yoshikawa
Aya Yoshikawa
TITomoko Ishii
Tomoko Ishii
MTMasakazu Toi
Masakazu Toi
Photoacoustic (PA) imaging (PAI) has been shown to be a promising tool for non-invasive blood vessel imaging. A PAI system comprising a hemispherical detector array (HDA) has been reported previously as a method providing high morphological reproducibility. However, further improvements in diagnostic capability will require improving the image quality of PAI and fusing functional and morphological imaging. Our newly developed PAI system prototype not only enhances the PA image resolution but also acquires ultrasonic (US) B-mode images at continuous positions in the same coordinate axes. In addition, the pulse-to-pulse alternating laser irradiation shortens the measurement time difference between two wavelengths. We scanned extremities and breasts in an imaging region 140 mm in diameter and obtained 3D-PA images of fine blood vessels, including arterioles and venules. We could estimate whether a vessel was an artery or a vein by using the S-factor obtained from the PA images at two wavelengths, which corresponds approximately to the haemoglobin oxygen saturation. Furthermore, we observed tumour-related blood vessels around breast tumours with unprecedented resolution. In the future, clinical studies with our new PAI system will help to elucidate various mechanisms of vascular-associated diseases and events.

19 December 2016 in Breast Cancer Research
Verified
Journal Article
Open access
PDF file
NUNatsue Uehiro
Natsue Uehiro
FSFumiaki Sato
Fumiaki Sato
FPFengling Pu
Fengling Pu
STSunao Tanaka
Sunao Tanaka
MKMasahiro Kawashima
Masahiro Kawashima
MTMasakazu Toi
Masakazu Toi
Circulating cell-free DNA (cfDNA) has recently been recognized as a resource for biomarkers of cancer progression, treatment response, and drug resistance. However, few have demonstrated the usefulness of cfDNA for early detection of cancer. Although aberrant DNA methylation in cfDNA has been reported for more than a decade, its diagnostic accuracy remains unsatisfactory for cancer screening. Thus, the aim of the present study was to develop a highly sensitive cfDNA-based system for detection of primary breast cancer (BC) using epigenetic biomarkers and digital PCR technology. Array-based genome-wide DNA methylation analysis was performed using 56 microdissected breast tissue specimens, 34 cell lines, and 29 blood samples from healthy volunteers (HVs). Epigenetic markers for BC detection were selected, and a droplet digital methylation-specific PCR (ddMSP) panel with the selected markers was established. The detection model was constructed by support vector machine and evaluated using cfDNA samples. The methylation array analysis identified 12 novel epigenetic markers (JAK3, RASGRF1, CPXM1, SHF, DNM3, CAV2, HOXA10, B3GNT5, ST3GAL6, DACH1, P2RX3, and chr8:23572595) for detecting BC. We also selected four internal control markers (CREM, GLYATL3, ELMOD3, and KLF9) that were identified as infrequently altered genes using a public database. A ddMSP panel using these 16 markers was developed and detection models were constructed with a training dataset containing cfDNA samples from 80 HVs and 87 cancer patients. The best detection model adopted four methylation markers (RASGRF1, CPXM1, HOXA10, and DACH1) and two parameters (cfDNA concentration and the mean of 12 methylation markers), and, and was validated in an independent dataset of 53 HVs and 58 BC patients. The area under the receiver operating characteristic curve for cancer-normal discrimination was 0.916 and 0.876 in the training and validation dataset, respectively. The sensitivity and the specificity of the model was 0.862 (stages 0-I 0.846, IIA 0.862, IIB-III 0.818, metastatic BC 0.935) and 0.827, respectively. Our epigenetic-marker-based system distinguished BC patients from HVs with high accuracy. As detection of early BC using this system was comparable with that of mammography screening, this system would be beneficial as an optional method of screening for BC.