Risks of subsequent primary cancers among breast cancer survivors according to hormone receptor status

Abstract

Background This study was aimed at examining the risks of subsequent primary cancers (SPCs) among breast cancer survivors by hormone receptor (HR) status and age at diagnosis. Methods Data from 12 Surveillance, Epidemiology, and End Results registries were used to identify 431,222 breast cancer survivors (at least 1 year) diagnosed between the ages of 20 and 84 years from 1992 to 2015. Risks of SPCs were measured as the standardized incidence ratio (SIR) and the excess absolute risk (EAR) per 10,000 person‐years. Poisson regression was used to test the difference in SIRs by HR status. Results In comparison with the general population, the risk of new cancer diagnoses among survivors was 20% higher for those with HR‐positive cancers (SIR, 1.20; 95% confidence interval [CI], 1.19‐1.21; EAR, 23.3/10,000 person‐years) and 44% higher for those with HR‐negative cancers (SIR, 1.44; 95% CI, 1.41‐1.47; EAR, 45.2/10,000 person‐years), with the risk difference between HR statuses statistically significant. The higher risk after HR‐negative cancer was driven by acute nonlymphocytic leukemia and breast, ovarian, peritoneal, and lung cancers. By age at diagnosis, the total EAR per 10,000 person‐years ranged from 15.8 (95% CI, 14.1‐17.5; SIR, 1.11) among late‐onset (age, 50‐84 years) HR‐positive survivors to 69.4 (95% CI, 65.1‐73.7; SIR, 2.24) among early‐onset (age, 20‐49 years) HR‐negative survivors, with subsequent breast cancer representing 73% to 80% of the total EAR. After breast cancer, the greatest EARs were for ovarian cancer among early‐onset HR‐negative survivors, lung cancer among early‐ and late‐onset HR‐negative survivors, and uterine corpus cancer among late‐onset HR‐positive survivors. Conclusions Risks of SPCs after breast cancer differ substantially by subtype and age. This suggests that more targeted approaches for cancer prevention and early‐detection strategies are needed in survivorship care planning.

Relationship between metastasis and second primary cancers in women with breast cancer

“…This indicates that in the case of distant MBC patients, analysis of lung lesions as primary or metastasis is essential; hence, SPCs should be considered. A significantly higher risk of second primary thyroid cancer was also observed in our study, which is consistent with previous studies ( 21 – 23 ). Moreover, our results show a gradient in risk with metastatic modality (SIR: NMBC: 1.72 vs. MBC-regional node: 2.35 vs. MBC-distant organ: 2.77), and the prognosis of distant MBC was poor after diagnosis with second primary thyroid cancer.…”

Estimation of secondary cancer projected risk after partial breast irradiation at the 1.5 T MR-linac

“…All breast cancer patients, independent of radiotherapy, have a higher risk to develop second cancers, most commonly of the lung, esophagus and thyroid compared to the general population [ 41 , 42 ]. This risk increases considerably for irradiated patients [ 43 ].…”

Epidemiology of Second Non-breast Primary Cancers among Survivors of Breast Cancer: A Korean Population–Based Study by the SMARTSHIP Group

“…The incidence of SNBPC has been evaluated in several studies from diverse populations [6][7][8][9][10][11][12][13][14][16][17][18][19]. The studies examined databases from various sources, including nationwide population-based data, regional registries, or institutional cohorts, to obtain comprehensive information on SNBPC (Table 6).…”

“…Previous studies have shown that various types of SNBPC occurred after breast cancer treatment [6][7][8][9][10][11][12][13]. Moreover, the risk of developing SNBPC among survivors of breast cancer significantly exceeds that in women without cancer in the general population [8,11,14]. Furthermore, patients with SNBPC may come across complicated medical issues caused by a previous treatment for breast cancer.…”