Disparities in Access to Systemic Treatment for Breast Cancer in Thailand and Major Asian Territories / 한국유방암학회지

Purpose@#Breast cancer (BC) treatment has shifted from chemotherapy to targeted therapy.Several targeted agents have demonstrated an improvement in survival. Given that national healthcare resources were correlated with the cancer mortality-to-incidence ratio, we compared access to BC drugs in Thailand with that in other Asian countries. @*Methods@#BC experts involved in the Breast International Group (BIG)-Asia in six representative groups for countries or special administrative region (SAR) in Asia (Hong Kong SAR, Japan, Korea, Taiwan, Thailand, and Singapore) were invited to participate in the survey. The questionnaire addressed national health reimbursement schemes, molecular testing for early BC (EBC), availability and accessibility of BC drugs. Accessibility and reimbursement of the drugs were reported based on their listing as essential medicines in the World Health Organization Model List of Essential Medicines (WHO-EML) and their nomination as effective drugs in the European Society for Medical Oncology-Magnitude of Clinical Benefit Scale (ESMO-MCBS). The study was approved by all participating BIG-Asia organizations in November 2021. @*Results@#Genomic tests for EBC were non-reimbursable in all surveyed territories.Reimbursement and co-payment of BC drugs vary between and within these regions (particularly Thailand). Most drugs in the WHO-EML and ESMO-MCBS (A/B for EBC and 4/5 for advanced BC) were accessible in all surveyed territories. However, the accessibility of effective but costly WHO-EML and ESMO-MCBS drugs was not uniform in Thailand. There was an evident disparity for individuals covered by the Thai Social Security/Universal Health Coverage schemes. @*Conclusion@#Essential BC drugs are generally accessible in selected BIG-Asia countries or SAR. There is a disparity in accessing high-cost drugs in Thailand compared with other Asian territories.

Validation of a Risk Score Incorporating Tumor Characteristics into the American Joint Committee on Cancer Anatomic Stage for Breast Cancer / 한국유방암학회지

PURPOSE: The American Joint Committee on Cancer 8th edition (AJCC8) prognostic stage (PS) was implemented January 1, 2018, but it is complex due to multiple permutations. A North American group proposed a simpler system using the anatomic stage with a risk score system (RSS) of 1 point each for grade 3 tumor and human epithelial growth factor receptor 2 (HER2) and estrogen receptor (ER) negativity. Here we aimed to evaluate this risk score system with our database of Asian breast cancer patients and compare it against the AJCC8 PS. METHODS: Patients diagnosed with breast cancer stage I–IV in 2006–2012 were identified in the SingHealth Joint Breast Cancer Registry. Five-year breast cancer-specific survival (CSS) and overall survival (OS) were calculated for each anatomic stage according to the risk score and compared with the AJCC8 PS. RESULTS: A total of 6,656 patients were analyzed. The median follow-up was 61 (interquartile range, 37–90) months. There was a high receipt of endocrine therapy (84.6% of ER+ patients), chemotherapy (84.3% of node-positive patients), and trastuzumab (86.0% of HER2+ patients). Within each anatomic stage, there were significant differences in survival in all sub-stages except IIIB. On multivariate analysis, the hazard ratio for negative ER was 1.74 (1.48–2.06), for negative HER2 was 1.49 (1.26–1.74), and for grade 3 was 1.84 (1.55–2.19). On multivariate analysis controlled for age, ethnicity, and receipt of chemotherapy, the RSS (Akaike information criterion [AIC] = 10,649.45; Harrell's Concordance Index [C] = 0.85) was not inferior to the AJCC8 PS (AIC = 10,726.65; C = 0.84) for CSS, nor was the RSS (AIC = 14,714.4; C = 0.82) inferior to the AJCC8 PS (AIC = 14,784.69; C = 0.81) for OS. CONCLUSION: The RSS is comparable to the AJCC8 PS for a patient population receiving chemotherapy as well as endocrine- and HER2-targeted therapy and further stratifies stage IV patients.

BioPATH: A Biomarker Study in Asian Patients with HER2+ Advanced Breast Cancer Treated with Lapatinib and Other Anti-HER2 Therapy / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: BioPATH is a non-interventional study evaluating the relationship of molecular biomarkers (PTEN deletion/downregulation, PIK3CA mutation, truncated HER2 receptor [p95HER2], and tumor HER2 mRNA levels) to treatment responses in Asian patients with HER2+ advanced breast cancer treated with lapatinib and other HER2-targeted agents. MATERIALS AND METHODS: Female Asian HER2+ breast cancer patients (n=154) who were candidates for lapatinib-based treatment following metastasis and having an available primary tumor biopsy specimen were included. The primary endpoint was progression-free survival (PFS). Secondary endpoints were response rate, overall survival on lapatinib, correlation between biomarker status and PFS for any previous trastuzumab-based treatment, and conversion/conservation rates of the biomarker status between tissue samples collected at primary diagnosis and at recurrence/metastasis. Potential relationships between tumor mRNA levels of HER2 and response to lapatinib-based therapy were also explored. RESULTS: p95HER2, PTEN deletion/downregulation, and PIK3CA mutation did not demonstrate any significant co-occurrence pattern and were not predictive of clinical outcomes on either lapatinib-based treatment or any previous trastuzumab-based therapy in the metastatic setting. Proportions of tumors positive for p95HER2 expression, PIK3CA mutation, and PTEN deletion/down-regulation at primary diagnosis were 32%, 31.2%, and 56.2%, respectively. Despite limited availability of paired samples, biomarker status patterns were conserved in most samples. HER2 mRNA levels were not predictive of PFS on lapatinib. CONCLUSION: The prevalence of p95HER2 expression, PIK3CA mutation, and PTEN deletion/downregulation at primary diagnosis were similar to previous reports. Importantly, no difference was observed in clinical outcome based on the status of these biomarkers, consistent with reports from other studies.

Patient Management with Eribulin in Metastatic Breast Cancer: A Clinical Practice Guide / 한국유방암학회지

Eribulin, an antimicrotubule chemotherapeutic agent, is approved for the treatment of pretreated metastatic breast cancer (mBC) based on the positive outcomes of phase II and phase III clinical trials, which enrolled mainly Western patients. Eribulin has recently been approved in an increasing number of Asian countries; however, there is limited clinical experience in using the drug in certain countries. Therefore, we established an Asian working group to provide practical guidance for eribulin use based on our clinical experience. This paper summarizes the key clinical trials, and the management recommendations for the reported adverse events (AEs) of eribulin in mBC treatment, with an emphasis on those that are relevant to Asian patients, followed by further elaboration of our eribulin clinical experience. It is anticipated that this clinical practice guide will improve the management of AEs resulting from eribulin treatment, which will ensure that patients receive the maximum treatment benefit.