Risk of second malignancies in long-term survivors of childhood cancer.

INTRODUCTION: Childhood cancer survivors are known to be at increased risk for second malignancies. PATIENTS AND METHODS: The risk of second malignancies was assessed in 1368 5-year survivors of childhood cancer treated in the Emma Children's Hospital AMC in Amsterdam. The median follow-up time was 16.8 years. RESULTS: Sixty two malignancies were observed against 5.4 expected, yielding a standardised incidence ratio (SIR) of 11.2 (95% confidence interval: 8.53-14.4; absolute excess risk: 3.2 per 1000 person-years). New observations were the strongly increased risks of meningiomas (SIR=40) and basal cell carcinomas (SIR=9). Patients whose treatment involved radiotherapy had a 2-fold increased second cancer risk compared to patients with chemotherapy alone. DISCUSSION: The relative risk of second malignancies does not decrease till at least 30 years of follow-up. With aging of the survivor cohort this results in a strong increase of the AER, due to the rising background risk of cancer with age.

Hypertension in long-term survivors of childhood cancer: a nested case-control study.

AIM OF THE STUDY: To examine risk factors for developing hypertension in childhood cancer survivors (CCS). METHODS: We conducted a nested case-control study of risk for hypertension within a cohort of 1362 childhood cancer survivors treated between 1966 and 1996 in the Emma's Children's Hospital/Academic Medical Center in the Netherlands. Detailed information on treatment and several lifestyle factors was collected for 44 cases with hypertension and 123 matched controls. Odds ratios (ORs) for hypertension were calculated by conditional logistic regression analysis. RESULTS: Body Mass Index (BMI) was the only significant risk factor associated with the occurrence of hypertension (OR 3.95; 95% confidence interval (CI) 1.7-9.1 for BMI25kg/m(2) compared to BMI<25kg/m(2)). However, cisplatin, cyclophosphamide and radiotherapy (RT) to the abdominal region were all associated with non-significant risk increases (ORs of 4.3, 2.1, and 1.8, respectively). CONCLUSION: Our results show that BMI is the most important risk factor for hypertension following treatment of childhood cancer, emphasising the need for CCS to maintain a normal weight.

Long-term cause-specific mortality among five-year survivors of childhood cancer.

BACKGROUND: The purpose of our study was to assess long-term cause-specific mortality of 5-year childhood cancer survivors. PROCEDURE: The study population consisted of 1,378 patients who had been treated for childhood cancer in The Netherlands between 1966 and 1996 and survived at least 5 years; follow-up was complete for 99% of survivors. Cause-specific mortality was compared with general population rates to assess relative and absolute excess risks of death (standardized mortality ratio (SMR) and AER). RESULTS: After a median follow-up of 16.1 years, 120 patients had died. The overall SMR was 17-fold (95% CI: 14.3-20.6) increased compared to the general population. Our cohort experienced an excess of 7 deaths per 1,000 person-years. Patients who received combined modality treatment and were treated for at least one recurrence experienced the highest risk of death (SMR = 92.3; AER = 37.0 per 1,000 person-years). The SMR appeared to stabilize at an about 4 to 5-fold increased risk of death after 20 years of follow-up. Only after more than 20 years of follow-up excess mortality due to other causes than the primary cancer exceeded mortality from the primary childhood cancer (2.3 vs. 0.3/1,000 patients/year). The SMR for all causes other than primary cancer was 5.4 in 25-year survivors. The overall risks of death strongly decreased with increasing attained age, with an SMR of 1.6 (n.s.) and an AER of 0.3 per 1,000 person-years for survivors of 30 years or older. CONCLUSIONS: The first primary cancer contributes most to the absolute excess risk of death in 5-year survivors of childhood cancer, but after 25 years childhood cancer mortality is negligible. Relative risk of death due to other causes is still significantly increased after 25 years of follow-up.