Addressing the Younger Age at Onset in Breast Cancer Patients in Asia: An Age-Period-Cohort Analysis of Fifty Years of Quality Data from the International Agency for Research on Cancer

Abstract

Introduction. There is an established fact that Asian breast cancer patients are, on average, younger than their European counterparts. This study aimed to utilize the data from the Cancer Incidence in Five Continents I through XIII (published by the International Agency for Research on Cancer) to examine what contributes to the younger age at onset in the Asian population. Material and Methods. Data (number of breast cancer cases and corresponding population figures) for 29 registries in Europe and 9 registries in Asia for the period of 1953–2002 was accessioned and pooled to form two distinct populations, Asia and Europe. The age specific rates were defined and analyzed cross-sectionally (period wise) and longitudinally (cohort wise). The magnitude and the pattern of age specific rates were analyzed using the age-period-cohort analysis. The constrained generalized linear model with a priority assumption of cohort effect as contributing factor to changing rates was used to analyze the data. Result. During the last 50 years, the rate of breast cancer increased for both populations with an estimated annual percent change of 1.03% (with 95% CI of 1.029, 1.031) for Asia and 1.016% (95% CI of 1.015, 1.017) for Europe. There were stronger cohort effects in the magnitude of rates among the Asian population compared to the European population. The cohort effects, expressed as the rate ratio with cohort born in 1970 as reference, ranged from 0.06 (95% CI 0.05, 0.08) to 0.94 (95% CI 0.93, 0.96) for Asians and 0.35 (95% CI 0.33, 0.36) to 1.03 (95% CI 1.02, 1.04) for Europeans. The estimated longitudinal age specific rates (adjusted for cohort and period effects) showed similar patterns between the two populations. Conclusion. It was concluded that a strong cohort effect contributes to the younger age at onset among Asian breast cancer patients.

Survival rates of patients with breast cancer in countries in the Eastern Mediterranean Region: a systematic review and meta-analysis

“…Also, the results from a 2016 study in Canada (21) and a 2017 Iranian study (22) confirm our findings. Some research has reported that the age of onset of breast cancer in women of the EMR and also Asian women is lower than their European and American counterpart (23). Breast cancer is a rare disease in young women, however the clinical and pathological outcomes are more aggressive than in older patients (20,21).…”

MLL1 promotes cervical carcinoma cell tumorigenesis and metastasis through interaction with β-catenin

“…Cervical carcinoma has become the fourth most common cancer in women in the world 1. The 5-year overall survival of cervical cancer is ~60% in all stages due to dramatic advances in screening and effective treatment 2.…”

A Prospective Follow-up Study of the Relationship between C-Reactive Protein and Human Cancer Risk in the Chinese Kailuan Female Cohort

“…Although the strongest associations with breast cancer were observed in younger women in our study, the case numbers for other tumor sites did not allow for stratified analyses by age. Considering that the incidence of lung cancer and CRC sharply increases with age and the average age at onset is slightly higher as compared with breast cancer, and the fact that breast cancer occurs at a generally younger age in Asian women with the highest rates apparent in those 45 to 50 years old (29), it is possible that the dynamics of our cohort are not yet conducive to detecting a significantly increased risk of CRC and lung cancer. This may particularly be the case if elevated levels of CRP, and the underlying processes contributing to these higher levels, have induction periods for carcinogenesis that vary by tumor type.…”