Risk of developing chronic myeloid neoplasms in well-differentiated thyroid cancer patients treated with radioactive iodine.

Exposure to ionizing radiation increases the risk of myelodysplastic syndromes (MDS) and myeloproliferative neoplasms (MPN), but such risks are not known in well-differentiated thyroid cancer (WDTC) patients treated with radioactive iodine (RAI). A total of 148 215 WDTC patients were identified from Surveillance, Epidemiology and End Results registries between 1973 and 2014, of whom 54% underwent definitive thyroidectomy and 46% received adjuvant RAI. With a median follow-up of 6.6 years, 77 and 66 WDTC patients developed MDS and MPN, respectively. Excess absolute risks for MDS and MPN from RAI treatment when compared to background rates in the US population were 6.6 and 8.1 cases per 100 000 person-years, respectively. Compared to background population rates, relative risks of developing MDS (3.85 (95% confidence interval, 1.7-7.6); P=0.0005) and MPN (3.13 (1.1-6.8); P=0.012) were significantly elevated in the second and third year following adjuvant RAI therapy, but not after thyroidectomy alone. The increased risk was significantly associated with WDTC size ⩾2 cm or regional disease. Development of MDS was associated with shorter median overall survival in WDTC survivors (10.3 vs 22.5 years; P<0.001). These data suggest that RAI treatment for WDTC is associated with increased risk of MDS with short latency and poor survival.

Decision-making and quality of life in older adults with acute myeloid leukemia or advanced myelodysplastic syndrome.

Older patients with acute myeloid leukemia (AML) and advanced myelodysplastic syndrome (aMDS) must decide between receiving intensive induction chemotherapy (IC) or nonintensive chemotherapy/best supportive care (NIC). Little information exists about what factors influence treatment decisions and what quality of life (QOL) is associated with treatment choices. We prospectively examined 43 patients 60 years or older who were interviewed at diagnosis and periodically over 1 year. IC choice was associated with younger age (66 vs 76 years, P=0.01) and AML diagnosis, but not with performance status, comorbidities, or QOL. In total, 63% of all patients reported not being offered other treatment options despite physician documentation of alternatives. Patient and physician estimates of cure differed significantly: 74% of patients estimated their chance of cure to be 50% or greater, yet for 89% of patients physician estimates of cure were 10% or less. IC patients experienced decreased QOL at 2 weeks, but rebounded to baseline and to NIC levels by 6 weeks. Initial QOL is not associated with treatment choice in older AML and aMDS patients. Regardless of treatment choice, patients report not being offered treatment options and overestimate their chances of cure. In IC patients, QOL decreases during hospitalization but rebounds after discharge.