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

Abstract

Background: Women diagnosed with breast cancer at young age have been shown to be at higher risk of developing a new primary cancer than women diagnosed at older ages, but little is known about whether adjustment for calendar year of breast cancer diagnosis, length of follow-up, and/or breast cancer treatment alters the risk pattern by age.Methods: We identified 304,703 women diagnosed with breast cancer during 1943 to 2006 in the Cancer Registries of Denmark, Norway, and Finland. Relative risks (RR) of subsequent non-breast cancer by age at cancer diagnosis were calculated using Poisson regression models adjusted for country, calendar period, length of follow-up, and treatment. Excess absolute risks (EAR) were also calculated.Results: The RR for all cancer sites except breast cancer decreased with increasing age both with and without adjustments. The RR and the EAR differed for each age at diagnosis category until the women reached their late 70s. Many specific cancer forms contributed to the overall risk pattern by age with endometrial cancer as 1 exception.Conclusions: The age at breast cancer diagnosis is an essential risk factor for being diagnosed with a new primary non-breast cancer and the level of risk for specific ages at diagnosis may hold for many years after the diagnosis. Occurrence of endometrial cancer after breast cancer seems to follow a distinct age pattern different from that seen for most other cancer types.Impact: Future studies should aim at exploring the underlying explanations for the age-related findings. Cancer Epidemiol Biomarkers Prev; 20(8); 1784-92. Ó2011 AACR.

Multiple primary cancers among colorectal cancer survivors in Queensland, Australia, 1996–2007

“…While other Australian [10,26,27] and international studies [7-9, 11, 14] have documented elevated risks of MPCs for CRC survivors, especially at the same site, such studies have only presented crude risks for subsequent cancers without controlling for potential confounders. Literature on adjusted relative risk estimates for MPCs is sparse and, with the exception of a recent breast cancer study [28], tends to only quantify the risks of treatment-induced cancers [15,16,29]. To our knowledge, no study has previously reported adjusted relative risk estimates for MPCs in Australia.…”

Risk of second cancers cancer after a first primary breast cancer: A systematic review and meta-analysis

“…Several population-based cancer registry studies [6][7][8][9][10][11] as well as studies involving several cancer registries [12,13], have evaluated the risk of developing second primary cancers among women diagnosed with a first primary breast cancer with respect to the general population. Most of these studies were derived from European data [6][7][8][9][10][11][12][13] and from the National Cancer Institute's Surveillance, Epidemiology (SEER) cancer registries in the United States [14][15][16].…”

“…Most of these studies were derived from European data [6][7][8][9][10][11][12][13] and from the National Cancer Institute's Surveillance, Epidemiology (SEER) cancer registries in the United States [14][15][16]. However, risk estimates provided by these studies are largely different, with an overall excess risk ranging between 15 and 45% for all cancer sites combined.…”

“…However, risk estimates provided by these studies are largely different, with an overall excess risk ranging between 15 and 45% for all cancer sites combined. Risk differences by age groups have also been examined in some of these studies [7,[10][11][12][13], showing that women diagnosed with breast cancer at premenopausal ages were at higher risk of developing a second cancer. In general, second primary cancers of the endometrium, ovary, melanoma, stomach and colon cancer have been reported to occur more frequently [6][7][8][9][10], although there is no consensus between studies.…”

Bilateral Salpingo-Oophorectomy Versus GnRH Analogue in the Adjuvant Treatment of Premenopausal Breast Cancer Patients: Cost-Effectiveness Evaluation of Breast Cancer Outcome, Ovarian Cancer Prevention and Treatment

“…[8,9] of ovarian cancer documented among estrogen receptor (ER)-positive breast cancer survivors aged <50 years is on average 21% higher compared to the expected number of ovarian cancers in the general population. [17] Since prophylactic BSO has been shown to dramatically reduce (up to 80-90%) the risk to develop ovarian cancer in women endowed with personal/familial risk factors as well as BRCA 1/2 gene mutation, [18,19] it could represent a valid clinical and cost-effectiveness option in the adjuvant treatment of pre-and perimenopausal hormone sensitive breast cancer patients, and an effective strategy for ovarian cancer prevention.…”