Cancer predisposition syndromes as risk factor for early second primary neoplasms after childhood cancer - a national cohort study

Background: Childhood cancer patients are at increased risk of second primary neoplasms (SPNs). We assessed incidence and risk factors for early SPNs with a focus on cancer predisposition syndromes (CPSs). Patients and methods: This cohort study used data from the Swiss Childhood Cancer Registry. We included patients with first primary neoplasms (FPN) until age 21 years from 1986 to 2015 and identified SPNs occurring before age 21. We calculated standardized incidence ratios (SIR) and absolute excess risks (AER) using Swiss population cancer incidence data and cumulative incidence of SPNs. We calculated hazard ratios (HR) of risk factors for SPNs using Fine and Gray competing risk regression. Results: Among 8,074 childhood cancer patients, 304 (4%) were diagnosed with a CPS and 94 (1%) developed early SPNs. The incidence of SPNs was more than 10-fold increased in childhood cancer patients compared to neoplasms in the general population (SIR 10.6, 95%-confidence interval [CI] 8.7-13.1) and the AER was 179/100,000 person-years (CI 139-219). Cumulative incidence of SPNs 20 years after FPN diagnosis was 23% in patients with CPSs and 3% in those without. Risk factors for SPNs were CPSs (HR 7.8, CI 4.8-12.7), chemotherapy (HR 2.2, CI 1.1-4.6), radiotherapy (HR 1.9, CI 1.2-2.9), hematopoietic stem cell transplantation (HR 1.8, CI 1-3.3), and older age (15-20 years) at FPN diagnosis (HR 1.9, CI 1.1-3.2). Conclusion: CPSs are associated with a high risk of SPNs before age 21 years. Identification of CPSs is important for appropriate cancer surveillance and targeted screening.

Incidence of second primary neoplasms among cancer survivors in the United States, 2000 through 2015.

1586 Background: The number of cancer survivors in the United States is projected to exceed 20 million by 2024. Survivors are at risk of developing a second primary neoplasm (SPN) – a leading cause of survivor death. We described the risk of developing a SPN among survivors of common cancers (smoking-related vs non-smoking-related) in the United States. Methods: We identified patients aged ≥18 years who were diagnosed with a primary cancer from the 10 sites with highest survival rates and stratified as smoking-related (urinary bladder, kidney & renal pelvis, uterine cervix, oral cavity & pharynx, and colon & rectum) and non-smoking related (prostate, thyroid, breast, corpus & uterus, and non-Hodgkin lymphoma) from Surveillance, Epidemiology, and End Results (2000-2015). SPN was defined as the first subsequent primary cancer occurring ≥2 months after first cancer diagnosis. Excess SPN risk was quantified using standardized incidence ratios (SIRs) stratified by sex. Results: A cohort of 2,908,349 patients (50.1% female) was identified and 260,267 (9.0%) developed SPN (7.6% of females and 10.3% of males). All index cancer sites were associated with a significant increase in SPN risk for females and males (except prostate cancer). Index smoking-related cancers (SIR range 1.20 – 2.17 for females and 1.12 – 1.91 for males) had higher increased risk of SPN than non-smoking-related cancers (SIR range 1.08 – 1.39 for females and 0.55 – 1.38 for males) relative to the general population. Conclusions: Nearly 10% of cancer survivors developed an SPN, and those with smoking-related cancers had higher risk. Given the increasing number of cancer survivors and importance of SPN as a cause of cancer death, these findings can improve secondary prevention and surveillance guidelines. [Table: see text]

Second primary cancers in long-term survivors of glioblastoma

Background Overall survival (OS) in glioblastoma (GBM) is poor at an average of 14 to 18 months, and long-term survivors (LTS) of GBM are rare. LTS of GBM, defined as surviving >5 years postdiagnosis, represent only 2% to 10% of all GBM patients. LTS of cancer are at high risk of developing second primary neoplasms. This study looks at occurrences of second primary neoplasms in LTS of GBM. Methods Records from adult patients newly diagnosed with GBM between January 1, 1998 and February 8, 2010, were retrospectively reviewed to identify LTS, defined as patients who survived ≥5 years. We focused on the identification of a new diagnosis of cancer occurring at least 2 years after the initial GBM diagnosis. Results We identified 155 LTS of GBM, with a median OS of 11.0 years (95% CI: 9.0 to 13.1 years) and a median follow-up of 9.6 years (95% CI: 8.7 to 10.7 years). In this cohort of patients, 13 (8.4%) LTS of GBM developed 17 secondary cancers. Eight could potentially be attributed to previous radiation and chemotherapy (skin cancer in radiation field [n = 4], leukemia [n = 2], low-grade glioma [n = 1], and sarcoma of the scalp [n = 1]). The other 9 cases included melanoma (n = 2), prostate cancer (n = 2), bladder cancer (n = 1), endometrioid adenocarcinoma (n = 1), basal cell carcinoma (n = 1), and renal cell carcinoma (n = 1). Conclusions Although second primary cancers are rare in GBM LTS, providers should continue close monitoring with appropriate oncologic care. Moreover, this highlights the need for survivorship care of patients with GBM.