Increased Risk for Second Primary Malignancies in Women with Breast Cancer Diagnosed at Young Age: A Population-Based Study in Taiwan

Abstract

Studies conducted in Western countries have reported excess risks for second primary malignancies after breast cancer. However, there is little documentation of ethnic differences in these excess risks. Asian women are characterized by younger age at diagnosis of breast cancer, but very few reports are available on the incidences and risks for second primary cancers in this region. Using population-based data from the Taiwan National Cancer Registry (TNCR) for the period 1979 to 2003, we quantified standardized incidence ratios and cumulative incidence of second cancers among 53,783 women with initial diagnoses of breast cancer. Age-specific incidences showed peaks among women in their 40s, and 1,085 cases (2.02%) developed nonbreast second primary cancers. The risk for second cancers differs significantly according to age at diagnosis of breast cancer. In comparison with women diagnosed when z50 years (standardized incidence ratio, 0.96; 95% confidence interval; 0.89-1.04), there were significantly greater risks for bone, corpus uterine, ovarian, thyroid, esophageal, kidney and lung cancers, nonmelanoma skin cancer, and leukemia or lymphoma in women diagnosed when <50 years (standardized incidence ratio, 1.43; 95% confidence interval, 1.29-1.58). The survival probabilities differed between breast cancer patients with and without second cancers (P < 0.001). After diagnosis of the second cancer, the median survival time was only 2.87 years. In conclusion, we confirmed that young age at diagnosis of breast cancer predicted a subsequently increased risk for second malignancies, and the second cancers indeed worsen survivorship in patients who survived breast cancer. (Cancer Epidemiol Biomarkers Prev 2008;17(10):2647 -55)

Risk of Primary Non–Breast Cancer After Female Breast Cancer by Age at Diagnosis

“…For most of the cancer sites or groups of cancer sites, we found a decrease in risk by increasing age at breast cancer though the magnitude of decrease varied. We found a steep decrease in risk for ovarian cancer by age at breast cancer in accordance with earlier studies (3)(4)(5); deleterious mutations in the BRCA1 and BRCA2 genes predisposing to breast cancer and ovarian cancer are likely to be the underlying explanation for this observation (27).…”

“…We found a weak U-shaped relationship between age at breast cancer and risk of endometrial cancer consistent with some previous studies (3,4), whereas 1 study reported a clear increasing trend by increasing age (5). The increase in risk of endometrial cancer by age confined to older age groups is in contrast to the findings for most cancer sites, where risk decreased by age throughout the age spectrum or no trend by age was seen.…”

“…Female survivors from breast cancer have been shown to be at increased risk of being diagnosed with additional primary cancers with risks consistently reported as higher among women diagnosed at younger ages relative to older ages (3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15). Younger breast cancer patients more often have unfavorable tumor characteristics and are more frequently treated with chemotherapy (16).…”

Comparison of Genome Aberrations Between Early-Onset and Late-Onset Breast Cancer

“…The classification of subtypes has been shown to provide prognostic information and etiologic mechanisms of breast cancer. In Taiwan, the young women breast cancer tends to be more luminal A type with higher ER and PR expression and less basallike subtype than that of the older women (Cheng et al, 2000;Lin et al, 2009), but with higher risk of second primary malignancy and worse prognosis (Lee et al, 2008;Mellemkjaer et al, 2006;Yu et al, 2006). This feature is quite distinct from that of western developed countries with high prevalence of more aggressive basal-like breast cancer in young women.…”

Oncologists Experience with Second Primary Cancer Screening: Current Practices and Barriers and Potential Solutions

“…Development of SPC is associated with poor survival (Lee et al, 2008;Schaapveld et al, 2008;Buchler et al, 2011), and screening for SPC is one of the key components of survivorship care (Cheung et al, 2009). Cancer screening can reduce the risk of dying from selected cancers through early detection, when the stage of cancer is more amenable to effective treatment (Shapiro et al, 1971;Timonen & Pyorala, 1977;Mandel et al, 1993).…”