Replication Study for the Association of Five SNPs Identified by GWAS and Trastuzumab-Induced Cardiotoxicity in Japanese and Singaporean Cohorts.

Trastuzumab (herceptin) is an effective drug for human epidermal growth factor receptor type 2 (HER2)-positive cancer. However, cardiotoxicity remains a serious complication. In our previous genome-wide association study (GWAS), we identified potential associations for five single nucleotide polymorphisms (SNPs) with trastuzumab-induced cardiotoxicity in a Japanese population. To validate this association, here we performed replication studies using Japanese and Singaporean case-control cohorts (Japan: 6 cases and 206 controls; Singapore: 22 cases and 178 controls). Although none of the SNPs showed a statistically significant association with trastuzumab-induced cardiotoxicity, we show that three (rs8032978, rs7406710 and rs9316695) and four (rs8032978, rs7406710, rs28415722 and rs11932853) SNPs had an effect in the same direction in the Japanese and the Singaporean cohort, respectively, as that in our previous study. Combining the previous study with the current replication studies, we find a strong association for two SNPs, rs8032978 and rs7406710, with trastuzumab-induced cardiotoxicity (Pcombined = 4.92 × 10-5 and 5.50 × 10-5, respectively). These data suggest that rs8032978 and rs7406710 could be predictive markers of trastuzumab-induced cardiotoxicity in Japanese and Singaporean populations, and support their potential use in clinical risk assessment. These findings offer a first step toward the development of clinically available markers for the potential risk of trastuzumab-induced cardiotoxicity as well as an improved understanding of the pathogenesis of this complication.

A Genome-Wide Association Study Identifies Five Novel Genetic Markers for Trastuzumab-Induced Cardiotoxicity in Japanese Population.

Trastuzumab has been administered to patients with human epidermal growth factor receptor 2 (HER2)-positive cancer, however, the cardiotoxicity is identified as one of the life-threatening toxicities. Clinically useful biomarker for trastuzumab-induced cardiotoxicity has been expected to be developed. To identify a novel genetic marker(s) determining the risk of trastuzumab-induced cardiotoxicity, we performed a first genome-wide association study (GWAS) in Japanese population. We enrolled 481 patients who had been treated with trastuzumab and carried out a GWAS using 11 cases (with cardiotoxicity) and 257 controls (without cardiotoxicity). Top 100 single nucleotide polymorphisms (SNPs) which revealed the smallest p values in GWAS (p = 7.60 × 10-7 - 2.01 × 10-4) were further examined using replication samples consisted of 14 cases and 199 controls. The combined analysis of the GWAS and replication study indicated possible association of five loci with trastuzumab-induced cardiotoxicity (rs9316695 on chromosome 13q14.3, rs28415722 on chromosome 15q26.3, rs7406710 on chromosome 17q25.3, rs11932853 on chromosome 4q25, and rs8032978 on chromosome 15q26.3, Pcombined = 6.00 × 10-6, 8.88 × 10-5, 1.07 × 10-4, 1.42 × 10-4, 1.60 × 10-4, respectively). Furthermore, we developed a risk prediction model for trastuzumab-induced cardiotoxicity using the five marker SNPs. The incidence of trastuzumab-induced cardiotoxicity in patients with risk score ≥5 was significantly higher (42.5%) compared to that in patients with score ≤ 4 (1.8%) (p = 7.82 × 10-15, odds ratio = 40.0). These findings suggest the potential to improve the ability of physicians to avoid the trastuzumab-induced cardiotoxicity for patients with HER2-positive cancer.

Percutaneous ultrasound-guided cryoablation for early-stage primary breast cancer: a follow-up study in Japan.

BACKGROUND: Ultrasound-guided percutaneous cryoablation (PCA) for early-stage breast cancer (ESBC) can be performed under local anesthesia in an outpatient clinic. This study continues a pilot stage to examine local control, safety, patient quality of life (QoL), satisfaction and cosmetic outcomes of cryoablation for ESBC. METHODS: PCA was performed under local anesthesia for patients with primary ESBC, followed by radiation and endocrine therapies. Oncologic outcomes were examined by imaging (mammography, ultrasound, MRI) at baseline and 1, 6, 12, 24, 36, and 60 months post-cryoablation. EQ-VAS, EQ-5D-5L, subjective satisfaction and Moiré topography were used to measure health-related QoL outcomes. RESULTS: Eighteen patients, mean aged 59.0 ± 9.0 years, mean tumor size 9.8 ± 2.3 mm, ER + , PR + (17/18), HER2-, Ki67 < 20% (15/18), underwent PCA and were followed for a mean of 44.3 months. No serious adverse events were reported, and no patients had local recurrence or distant metastasis in the 5-year follow-up. Cosmetic outcomes, satisfaction level, and QoL all improved post-cryoablation. Five-year average reduction rates of the cryolesion long, short, and depth diameters, on US, were 61.3%, 42.3%, and 22.8%, respectively, compared to the 86.2% volume reduction rate on MRI. The correlation coefficient between MRI and US measurement criteria was highest for the long diameter. During follow-up, calcification of the treated area was observed in 13/18 cases. CONCLUSION: Cryoablation for ESBC is an effective and safe procedure with excellent cosmetic outcomes and improved QoL. This study contributes to the growing evidence supporting cryoablation as a potential standard treatment for ESBC, given compliance to pre-defined patient selection criteria.

Association between genetic variants and the risk of nivolumab-induced immune-related adverse events.

Aim: We sought to identify the variants that could predict the risk of nivolumab-induced immune-related adverse events (irAEs) in patients with cancer. Patients & methods: We enrolled 622 Japanese patients and carried out a genome-wide association study. The associations for 507 single nucleotide polymorphisms (SNPs) showing p < 0.001 were further investigated using an independent cohort. Results: In the combined analysis, possible associations were found for a total of 90 SNPs. Although no SNPs were identified to be significantly associated with nivolumab-induced irAEs, the SNP most strongly associated with nivolumab-induced irAEs was rs469490. Conclusion: This study is an important hypothesis-generating study to guide future studies in larger and/or other ethnic cohorts.