Young adult cancer incidence trends in Taiwan and the U.S. from 2002 to 2016

Five-year survival prognosis of young, middle-aged, and elderly adult female invasive breast cancer patients by clinical and lifestyle characteristics

PURPOSE

Early-onset breast cancer incidence has been increasing globally and in Taiwan. However, previous studies have not comprehensively examined how clinical and lifestyle characteristics influence the 5-year survival of breast cancer diagnosed at different stages of adulthood.

METHODS

We analyzed the Taiwan National Cancer Registry and Cause of Death datasets to understand how clinical factors (including tumor and treatment characteristics) and lifestyle factors (including body mass index, cigarette smoking, and alcohol consumption) were associated with the 5-year survival of 8471 young, 57,695 middle-aged, and 14,074 elderly female adult invasive breast cancer patients respectively diagnosed at age 20-39, 40-64, and ≥ 65 years between 2002 and 2015, with mortality follow-up to 2020. Poisson regression was used for obtaining the crude and adjusted 5-year survival risk ratios.

RESULTS

Clinical and lifestyle characteristics were distributed differently but had mostly similar direction of association with 5-year survival for the three age groups. Receiving any treatment was associated with better survival, especially for elderly patients. Being underweight at initial cancer treatment was associated with worse survival than having normal weight, especially for elderly patients. Current smokers had worse survival than never smokers for middle-aged and elderly patients. The 5-year breast cancer-specific survival was not significantly higher for those of age 45-49 years than 40-44 years, despite the recommended starting screening age is 45 years in Taiwan.

CONCLUSION

Our findings contribute to the understanding of early-onset and later-onset female breast cancer characteristics and prognosis, which may inform surveillance and treatment strategies to achieve better breast cancer prognosis.

Breast Cancer Incidence Among US Women Aged 20 to 49 Years by Race, Stage, and Hormone Receptor Status

Importance

Breast cancer in young women has a less favorable prognosis compared with older women. Yet, comprehensive data on recent trends and how period and cohort effects may affect these trends among young women are not well-known.

Objective

To evaluate breast cancer incidence among young women in the US over a 20-year period by race and ethnicity, hormone receptor status (estrogen receptor [ER] and progesterone receptor [PR]), tumor stage, and age at diagnosis, as well as how period and cohort effects may affect these trends.

Design, Setting, and Participants

This cross-sectional study used data from Surveillance, Epidemiology, and End Results 17 registries (2000-2019). Women aged 20 to 49 years with a primary invasive breast cancer were included. Data were analyzed between February and June 2023.

Main Outcomes and Measures

Age-standardized incidence rates (ASIR), incidence rate ratios (IRR), and average annual percent changes (AAPC) stratified by race and ethnicity, hormone receptor status, tumor stage, and age at diagnosis.

Results

Out of 217 815 eligible women (1485 American Indian or Alaska Native [0.7%], 25 210 Asian or Pacific Islander [11.6%], 27 112 non-Hispanic Black [12.4%], 37 048 Hispanic [17.0%], 126 960 non-Hispanic White [58.3%]), the majority were diagnosed with an ER+/PR+ tumor (134 024 [61.5%]) and were diagnosed with a stage I tumor (81 793 [37.6%]). Overall, invasive breast cancer incidence increased (AAPC, 0.79; 95% CI, 0.42 to 1.15), with increasing trends across almost all racial and ethnic groups. ASIR increased for ER+/PR+ (AAPC, 2.72; 95% CI, 2.34 to 3.12) and ER+/PR- tumors (AAPC, 1.43; 95% CI, 1.00 to 1.87), and decreased for ER-/PR+ (AAPC, -3.25; 95% CI, -4.41 to -2.07) and ER-/PR- tumors (AAPC, -0.55; 95% CI, -1.68 to 0.60). For women aged 20 to 29 and 30 to 39 years, ASIRs were highest among non-Hispanic Black women (age 20-29 years: IRR, 1.53; 95% CI, 1.43 to 1.65; age 30-39 years: IRR, 1.15; 95% CI, 1.12 to 1.18). For women aged 40 to 49 years, ASIR was lower for non-Hispanic Black women (IRR, 0.96; 95% CI, 0.94 to 0.97) compared with non-Hispanic White women. Incidence rates increased for stages I and IV tumors but decreased for stage II and III tumors. Age-period-cohort analysis demonstrated both cohort and period effects on breast cancer incidence (P < .001).

Conclusions and Relevance

In this population-based cross-sectional analysis, an increase in breast cancer incidence rates among young US women and age-related crossover between non-Hispanic White and Black women were observed. Prevention efforts in young women need to adopt a targeted approach to address racial disparities in incidence rates observed at different age phases.

Landscape of young breast cancer under 35 years in China over the past decades: a multicentre retrospective cohort study (YBCC-Catts study)

Background

The proportion of young breast cancer patients in China is significantly higher than in Western countries, and the clinicopathological characteristics and clinical problems faced by patients in China are different from those in Western countries too, so there is an urgent need to conduct some studies for young breast cancer patients in Asia.

Methods

This study consisted of two breast cancer cohorts in China. The population-based cohort involved breast cancer cases diagnosed in 2000-2017 via cancer registration system, and we describe the epidemiological characteristics of the young breast cancer in China. The hospital-based cohort, patients eligible for enrollment were breast cancer in young women (≤35 years old) from eight centres in different regions of China, diagnosed and treated for the first time in six time periods (i.e., 2000, 2003, 2006, 2009, 2012, and 2015). Patient demographic characteristics and clinical features were compared among the six time periods using a trend test. The Kaplan-Meier method was used to generate survival curves, and the log-rank test was performed to compare OS and DFS. Univariate and multivariate analyses were carried out using Cox proportional hazards regression to estimate hazard ratios (HR) and 95% confidence intervals (CIs).

Findings

In the population-based cohort, age-specific incidence and age-standardised percentages of breast cancer cases younger than 35 years were increased. The proportion of breast cancer under the age of 35 is increasing more rapidly in rural areas than in urban areas. In the hospital-based cohort, a total of 1308 young breast cancer patients (≤35 years old) were collected. Proportion of patients treated with adjuvant taxane or anthracycline combined with taxane is gradually increasing over the six time periods, and the proportion of patients undergoing breast-conserving surgery is gradually increasing too. Meanwhile, the patients treated with combined ovarian function suppression (OFS) endocrine therapy gradually increased, and the duration of endocrine therapy gradually longer. There is an increasing trend in 5-year disease-free survival (DFS) rate for the total population in the six time periods between 2000 and 2015, but no significant difference in overall survival (OS) rate was observed. Early staging and longer duration of endocrine therapy were factors associated with a favorable prognosis.

Interpretation

The incidence of younger breast cancers under 35 years of age has gradually increased and the pattern of patient care has changed significantly over time, which may contribute to the improved prognosis of younger breast cancer patients.

Funding

Beijing Medical Award Foundation (YXJL-2020-0941-0763), Beijing Hope Run Special Fund of Cancer Foundation of China (LC2021L04), Chinese Academy of Medical Sciences Clinical Translational and Medical Research Fund (2022-I2M-C&T-A-014).

Sulfur Metabolism of the Gut Microbiome and Colorectal Cancer: The Threat to the Younger Generation

Colorectal cancer diagnosed in individuals under 50 years old is called early-onset colorectal cancer (EOCRC), and its incidence has been rising worldwide. Simultaneously occurring with increasing obesity, this worrisome trend is partly explained by the strong influence of dietary elements, particularly fatty, meaty, and sugary food. An animal-based diet, the so-called Western diet, causes a shift in dominant microbiota and their metabolic activity, which may disrupt the homeostasis of hydrogen sulfide concentration. Bacterial sulfur metabolism is recognized as a critical mechanism of EOCRC pathogenesis. This review evaluates the pathophysiology of how a diet-associated shift in gut microbiota, so-called the microbial sulfur diet, provokes injuries and inflammation to the colonic mucosa and contributes to the development of CRC.