Jessica St. Louis

Breast cancer in China

The health burden of cancer is increasing in China, with more than 1·6 million people being diagnosed and 1·2 million people dying of the disease each year. As in most other countries, breast cancer is now the most common cancer in Chinese women; cases in China account for 12·2% of all newly diagnosed breast cancers and 9·6% of all deaths from breast cancer worldwide. Chinas proportional contribution to global rates is increasing rapidly because of the populations rising socioeconomic status and unique reproductive patterns. In this Review we present an overview of present control measures for breast cancer across China, and emphasise epidemiological and socioeconomic diversities and disparities in access to care for various subpopulations. We describe demographic differences between China and high-income countries, and also within geographical and socioeconomic regions of China. These disparities between China and high-income countries include younger age at onset of breast cancer; the unique one-child policy; lower rates of provision and uptake for screening for breast cancer; delays in diagnosis that result in more advanced stage of disease at presentation; inadequate resources; and a lack of awareness about breast cancer in the Chinese population. Finally, we recommend key measures that could contribute to improved health outcomes for patients with breast cancer in China.

Challenges to effective cancer control in China, India, and Russia

Cancer is one of the major non-communicable diseases posing a threat to world health. Unfortunately, improvements in socioeconomic conditions are usually associated with increased cancer incidence. In this Commission, we focus on China, India, and Russia, which share rapidly rising cancer incidence and have cancer mortality rates that are nearly twice as high as in the UK or the USA, vast geographies, growing economies, ageing populations, increasingly westernised lifestyles, relatively disenfranchised subpopulations, serious contamination of the environment, and uncontrolled cancer-causing communicable infections. We describe the overall state of health and cancer control in each country and additional specific issues for consideration: for China, access to care, contamination of the environment, and cancer fatalism and traditional medicine; for India, affordability of care, provision of adequate health personnel, and sociocultural barriers to cancer control; and for Russia, monitoring of the burden of cancer, societal attitudes towards cancer prevention, effects of inequitable treatment and access to medicine, and a need for improved international engagement.

Progress and remaining challenges for cancer control in Latin America and the Caribbean

Cancer is one of the leading causes of mortality worldwide, and an increasing threat in low-income and middle-income countries. Our findings in the 2013 Commission in The Lancet Oncology showed several discrepancies between the cancer landscape in Latin America and more developed countries. We reported that funding for health care was a small percentage of national gross domestic product and the percentage of health-care funds diverted to cancer care was even lower. Funds, insurance coverage, doctors, health-care workers, resources, and equipment were also very inequitably distributed between and within countries. We reported that a scarcity of cancer registries hampered the design of credible cancer plans, including initiatives for primary prevention. When we were commissioned by The Lancet Oncology to write an update to our report, we were sceptical that we would uncover much change. To our surprise and gratification much progress has been made in this short time. We are pleased to highlight structural reforms in health-care systems, new programmes for disenfranchised populations, expansion of cancer registries and cancer plans, and implementation of policies to improve primary cancer prevention.

Epidemiology and pathophysiology of pregnancy-associated breast cancer: A review

The interactions between pregnancy and breast cancer (BC) are complex. Overall, parity is associated with long-term protective effects against BC, however in a small group of susceptible patients, pregnancy can lead to the development of a form of BC with a particularly poor prognosis. Pregnancy-associated breast cancer (PABC) remains an under-studied but important and growing clinical problem worldwide. Several aspects of PABC, including risk factors and mechanisms involved in its occurrence and aggressiveness, are incompletely understood. This review aims to summarize the epidemiology, biology, patho-physiology and clinical characteristics of PABC. We emphasize that age at first pregnancy, absence of breastfeeding and family history stand out as possible risk factors for developing PABC that ought to be incorporated into clinical tools for assessing a womans risk of developing PABC. Also, improved methods for identifying women at risk of developing PABC in the general population are needed.

Current and emerging therapies of HER2-positive metastatic breast cancer

The HER2 receptor as measured by immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH) is overexpressed in 15-20% of all breast cancers and traditionally represents adverse biology and a guarded prognosis, particularly in HER2 positive metastatic breast cancer (MBC). Trastuzumab and newer anti-HER2 targeting agents have significantly improved the clinical outcomes of patients with HER2 positive MBC. The development of new techniques has led to discovery of promising biomarkers that can lead to more precise selection of patients for anti-HER2 therapies. This paper summarizes these new biomarkers, useful in selecting patients for treatment with new and emerging therapies for HER2 positive MBC. Emerging next generation sequencing techniques have truly changed the landscape of HER2 positive MBC. Deployment of multiple anti-HER2 therapies in combination is a strategy which has yielded additive or even synergistic effects and has led to markedly improved patient outcomes in HER2+ MBC. In the future, in order to further improve the treatment of these patients and to reduce toxicities, we need to improve our understanding of HER2-dependent pathways and their function, and to develop further treatment combinations while optimizing selection of patients by identifying new biomarkers. The results of prospective studies using CTCs, cDNA and other promising new biomarkers are awaited with great interest.

Cervical cancer control in Latin America: A call to action.

Cervical cancer (CC) is second most common cause of cancer in Latin America and is a leading cause of cancer mortality among women. In 2015, an estimated 74,488 women will be diagnosed with CC in Latin America and 31,303 will die of the disease. CC mortality is projected to increase by 45% by 2030 despite human papillomavirus (HPV) vaccination and screening efforts. In this setting, the goal was of the current study was to examine CC control efforts in Latin America and identify deficiencies in these efforts that could be addressed to reduce CC incidence and mortality. The authors found that HPV vaccination has been introduced in the majority of Latin American countries, and there is now a need to monitor the success (or shortcomings) of these programs and to ensure that these programs are sustainable. This topic was also reviewed in light of emerging data demonstrating that visual inspection with acetic acid and HPV DNA testing without Papanicolaou tests have efficacy from a screening perspective and are good alternatives to cytology‐based screening programs. Overall, there is a need to build capacity for CC control in Latin America and the best strategy will depend on the country/region and must be tailored to meet the needs of the population as well as available resources. Cancer 2016;122:502–514.

Improving access to high-cost cancer drugs in Latin America: Much to be done

Lack of access to high‐cost medications is a complex issue at the intersection of economics, medicine, politics, and ethics, and it poses a significant threat to global health care. The problem is even more significant in low‐ and middle‐income countries, such as those in Latin America, where governments and individuals struggle to pay for products that are priced at several times the level of their per capita gross domestic product. In this review, we examine the determinants for increasing drug costs and how Latin American countries face this burgeoning crisis. We emphasize that a number of opportunities and strategies to reduce costs and improve access exist and should be identified and implemented, ideally within a regional approach with multiple stakeholders involved and based on systematic and transparent cost‐effectiveness analyses. Cancer 2017;123:1313–1323.

An alert to Latin America: Current human papillomavirus vaccination trends highlight key barriers to successful implementation

&NA; Human papillomavirus vaccine programs run the risk of repeating the problems associated with Papanicolaou testing programs in low‐income and middle‐income countries: an efficient, life‐saving tool that unfortunately is underused for cancer prevention. There is a great need for vigilance in the ongoing implementation of the human papillomavirus vaccine in Latin America.

Intermittent Letrozole Therapy for Metastatic Breast Cancer: Case Reports and Literature Review

Aromatase inhibitors (AIs) are considered standard first-line endocrine therapy for estrogen receptore positive (ERþ) metastatic breast cancer in postmenopausal women. Disease resistance to AIs commonly develops during therapy. In terms of time to disease resistance, preclinical experiments indicate that intermittent treatment in responsive tumors is superior to continuous treatment, possibly owing to amelioration of putative induced mechanisms of disease resistance. The aim of this study was to investigate the effectiveness and safety of intermittent aromatase inhibition in patients with ERþ metastatic breast cancer. Three patients with hormone receptorepositive metastatic breast cancer enrolled on a protocol offering intermittent letrozole treatment guided by monitoring changes in each individual’s measurable serial serum CA 15-3 (carcinoma antigen 15-3) levels. One patient was on letrozole for 46 (37%) of 123 weeks of total study duration; a second patient was on letrozole for 99 (45%) of 219 weeks of total study duration; and a third patient has been on letrozole for 22 (14.8%) of 149 weeks and remains on study. As expected, toxicities during the overall study period were minimal. Intermittent letrozole therapy guided by serum CA 15-3 levels was well tolerated, safe, and resulted in prolonged responses and time off active therapy in the 3 cases presented. New insights into mechanisms of estrogen dependence and endocrine therapy resistance are also possible with this novel approach. Although this study closed prematurely owing to poor accrual, its results suggest that a larger proof-ofprinciple trial is now even more merited.

Disparities in Breast, Lung, and Cervical Cancer Trials Worldwide

Purpose As cancer burden has risen worldwide, physicians, patients, and their advocates have become aware that the clinical cancer trial research paradigm is not ubiquitous. Furthermore, the number and characteristics of trials that are registered in low- and middle-income countries (LMICs) compared with that in high-income countries (HICs) are unknown. Methods We collected retrospective data on trials for breast, lung, and cervical cancer registered in ClinicalTrials.gov or with the WHO International Clinical Trial Registry Platform between 2010 and 2017. The data were then classified as trials within LMICs or HICs using definitions from the World Bank. Results Included in these analyses were 6,710 trials, of which 3,164 (47%) were breast cancer trials, 3,283 (49%) were lung cancer trials, and 263 (4%) were cervical cancer trials. There were 1,951 (29%) trials from LMICs and 4,759 (71%) trials from HICs (P < .001). Although the proportion of phase III trials in HICs versus LMICs was similar (18% v 17%; P = .66), the number of phase I trials in LMICs was significantly lower than that of HICs (20% v 2%; P < .001). For several LMICs with the highest mortality-to-incidence ratios for breast, lung, or cervical cancer, there were no cancer trials registered in the registration data bases searched for this work. Conclusion There are differences in access to cancer clinical trials in LMICs compared with HICs. Several factors, such as excessive cost and a lack of infrastructure and expertise, may explain these differences.