For eleven years, scientists had followed a large cohort of breast cancer patients from the so-called EPIC study (European Prospective Investigation Into Cancer And Nutrition). The aim was to determine the risk of another primary tumor. The result in brief: Those who have already suffered from breast carcinoma have a significantly higher risk of tumor recurrence (not only in the other breast).
A total of 10,045 European women with previously invasive breast cancer were included in the 11-year follow-up. During this period, 492 new primary tumors were identified-140 of which were contralateral breast carcinomas that were excluded from the analysis. Factors such as age at onset of disease, pregnancy, BMI or smoking were collected by questionnaire and included in the calculation.
Using the standardized incidence ratio (SIR) – i.e., the ratio between observed and expected incidence (general population as a baseline) – the authors led by Fulvio Ricceri, Turin, concluded that the risk for the following cancers is significantly increased among breast cancer patients:
- Colorectal cancer (SIR 1.71; 95% CI 1.43-2.00).
- Lymphoma (1.80; 1.31-2.40)
- Melanoma (2.12; 1.63-2.70)
- Endometrial carcinomas (2.18; 1.75-2.70)
- Renal carcinomas (2.40; 1.57-3.52).
Relevant for aftercare
Overall, a breast cancer patient’s risk of developing a second primary tumor increased by 30% (compared to the reference population). Factors positively associated with tumor risk were young age at breast cancer diagnosis, active smoking status, and increased BMI. In contrast, an inverse association was seen for higher education, postmenopausal status , and full-term pregnancy.
According to the authors, the identification of risk factors is of particular importance for the clinic, since the ultimate goal is to prevent further primary tumors after breast cancer wherever possible or at least to detect them at an early stage. The follow-up of breast cancer patients including screening can be better defined and thus optimized by such results.
Source: Ricceri F, et al: Risk of second primary malignancies in women with breast cancer: results from the European prospective investigation into cancer and nutrition (EPIC). Int J Cancer 2015. doi: 10.1002/ijc.29462.
InFo ONCOLOGY & HEMATOLOGY 2015; 3(6): 2
