Female breast cancer patients have an increased risk of developing subsequent malignant diseases, but this issue is rarely discussed in regards to male breast cancer patients. Thus, we conducted a national survey that included 100,915 female and 578 male breast cancer patients to investigate the risk of second primary malignancy (SPM). During a follow-up period that included 529,782 person-years, 3,153 cases of SPM developed. Compared with the general population, the standardized incidence ratio (SIR) of SPM in breast cancer patients was 1.51 [95% confidence interval (CI): 1.46–1.56]. The observed risk was significantly higher in male patients (SIR 2.17, 95% CI 1.70–2.73) and in patients whose age at breast cancer diagnosis was 40 years or younger (SIR 3.39, 95% CI 2.80–4.07), comparing to age-matched general population. Compared with the overall female population, the SIRs of female breast cancer patients with uterine (SIR: 2.66, 95% CI: 2.37–2.98), thyroid (SIR: 2.30, 95% CI: 2.02–2.62), and bone and soft tissue (SIR: 2.16, 95% CI: 1.56–2.91) cancers were significantly increased. Male breast cancer patients also displayed significantly higher SIRs for thyroid (SIR: 13.2, 95% CI: 1.60–47.69), skin (SIR: 8.24, 95% CI: 3.02–17.94) and head and neck (SIR: 4.41, 95% CI: 2.35–7.54) cancers. Among breast cancer patients, risk factors significantly associated with SPM included male gender, older age, chemotherapy treatment and comorbidity with liver cirrhosis. From our analysis, we concluded that the risk of SPM was significantly higher for both male and female breast cancer patients compared with the general population, suggesting that more intensive surveillance may be needed, especially in high-risk patients.

BackgroundCancer patients are at risk of thromboembolism. However, studies investigating the relationship between ovarian cancer and ischemic stroke are lacking. The objectives of this study were to assess the association between ovarian cancer and ischemic stroke, and to determine the predictive risk factors.MethodsOvarian cancer patients aged 20 years and older without antecedent cerebrovascular events and who were followed up for more than 1 year between 1 January 2003 and 31 December 2011 were recruited from the Taiwan National Health Insurance database. Hazard ratios (HRs) of stroke risk for ovarian cancer patients compared with an age- and comorbidity-matched cohort were calculated by Cox proportional regression analysis. The difference in cumulative ischemic stroke incidence between ovarian cancer patients and the matched cohort was analyzed with the Kaplan-Meier method and tested with the log-rank test.ResultsEach cohort (ovarian cancer and matched cohort) consisted of 8,810 individuals, with a median age of 49 years. After a median follow-up of 2.68 and 3.85 years, respectively, the ischemic stroke incidence was 1.38-fold higher in the ovarian cancer cohort than in the comparison cohort (9.4 versus 6.8 per 1,000 person-years), with an age- and comorbidity-adjusted HR of 1.49 (P <0.001). The ischemic stroke risk imposed by ovarian cancer was more prominent in patients under 50 years old (HR 2.28; P <0.001) compared with patients 50 years and older (HR 1.33; P = 0.005). Significant risk factors predicting stroke development were age 50 years and older (HR 2.21; P <0.001), hypertension (HR 1.84; P <0.001), diabetes mellitus (HR 1.71; P <0.001), and treatment with chemotherapy (HR 1.45; P = 0.017), especially platinum-based regimens.ConclusionsOvarian cancer patients were at an increased risk of developing ischemic stroke. Age, hypertension, diabetes, and chemotherapy treatment were independent risk factors.

To evaluate the risk of secondary primary malignancy (SPM) in patients with cervical cancer using a nationwide population-based dataset.Patients newly diagnosed with cervical cancer between 1997 and 2011 were identified using Taiwan's National Health Insurance database. Patients with antecedent malignancies were excluded. Standardized incidence ratios (SIRs) for SPM were calculated by comparing with the cancer incidence in the general population. Risk factors for cancer development were analyzed using Cox proportional hazard models.During the 14-year study period (follow-up of 223,062 person-years), 2004 cancers developed in 35,175 patients with cervical cancer. The SIR for all cancers was 1.56 (95% confidence interval, 1.50–1.63, P < 0.001). SIRs for follow-up periods of >10, 5 to 10, 1 to 5, and <1 year were 1.37, 1.51, 1.34, and 2.59, respectively. After the exclusion of SPM occurring within 1 year of cervical cancer diagnosis, SIRs were significantly higher for cancers of the esophagus (2.05), stomach (1.38), colon, rectum, and anus (1.36); lung and mediastinum (2.28), bone and soft tissue (2.23), uterus (3.76), bladder (2.26), and kidneys (1.41). Multivariate analysis showed that age ≥60 was a significant SPM risk factor (hazard ratio [HR] 1.59). Different treatments for cervical cancer, including radiotherapy (HR 1.41) and chemotherapy (HR 1.27), had different impacts on SPM risk. Carboplatin and fluorouracil independently increased SPM risk in cervical cancer patients.Patients with cervical cancer are at increased risk of SPM development. Age ≥60 years, chemotherapy, and radiotherapy are independent risk factors. Carboplatin and fluorouracil also increased SPM risk independently. Close surveillance of patients at high risk should be considered for the early detection of SPMs.