Radiation Dose and Volume to the Pancreas and Subsequent Risk of Diabetes Mellitus.

2019

2019 Jul 22

1460-2105

<p><strong>BACKGROUND: </strong>Childhood cancer survivors exposed to abdominal radiation (abdRT) are at increased risk for diabetes mellitus but the association between risk and radiation dose and volume is unclear.</p>

<p><strong>METHODS: </strong>Participants included 20,762 five-year survivors of childhood cancer (4,568 exposed to abdRT) and 4,853 siblings. For abdRT, we estimated maximum dose to abdomen, mean doses for whole pancreas, pancreatic head, body, tail, and percent pancreas volume receiving ≥10, ≥20, and ≥30Gy. Relative risks (RRs) were estimated with a Poisson model using generalized estimating equations, adjusted for attained age. All statistical tests were two-sided.</p>

<p><strong>RESULTS: </strong>Survivors exposed to abdRT (median age=31.6 years, range=10.2-58.3) were 2.92-fold more likely than siblings (95% confidence interval [CI]=2.02 to 4.23) and 1.60-times more likely than survivors not exposed to abdRT (95%CI=1.24 to 2.05) to develop diabetes. Among survivors treated with abdRT, greater attained age (RR(per 10 years)=2.11, 95%CI=1.70 to 2.62), higher body mass index (RR(BMI 30+)=5.00, 95%CI=3.19 to 7.83 with reference(BMI 18.5-24.9)), and increasing pancreatic tail dose were associated with increased diabetes risk in a multivariable model; an interaction was identified between younger age at cancer diagnosis and pancreatic tail dose with much higher diabetes risk associated with increasing pancreatic tail dose among those diagnosed at the youngest ages (p&lt;.001). Radiation dose and volume to other regions of the pancreas were not statistically significantly associated with risk.</p>

<p><strong>CONCLUSIONS: </strong>Among survivors treated with abdRT, diabetes risk was associated with higher pancreatic tail dose, especially at younger ages. Targeted interventions are needed to improve cardiometabolic health among those at highest risk.</p>

10.1093/jnci/djz152

J. Natl. Cancer Inst.

31329225

Endocrine Abnormalities in Aging Survivors of Childhood Cancer: A Report From the Childhood Cancer Survivor Study.

2016

2016 Jul 5

1527-7755

<p><strong>PURPOSE: </strong>The development of endocrinopathies in survivors of childhood cancer as they age remains understudied. We characterized endocrine outcomes in aging survivors from the Childhood Cancer Survivor Study on the basis of therapeutic exposures.</p>

<p><strong>PATIENTS AND METHODS: </strong>We analyzed self-reported conditions in 14,290 5-year survivors from the Childhood Cancer Survivor Study, with a median age 6 years (range, &lt; 1 to 20 years) at diagnosis and 32 years (range, 5 to 58 years) at last follow-up. Identification of high-risk therapeutic exposures was adopted from the Children's Oncology Group Long-Term Follow-Up Guidelines. Cumulative incidence curves and prevalence estimates quantified and regression models compared risks of primary hypothyroidism, hyperthyroidism, thyroid neoplasms, hypopituitarism, obesity, diabetes mellitus, or gonadal dysfunction between survivors and siblings.</p>

<p><strong>RESULTS: </strong>The cumulative incidence and prevalence of endocrine abnormalities increased across the lifespan of survivors (P &lt; .01 for all). Risk was significantly higher in survivors exposed to high-risk therapies compared with survivors not so exposed for primary hypothyroidism (hazard ratio [HR], 6.6; 95% CI, 5.6 to 7.8), hyperthyroidism (HR, 1.8; 95% CI, 1.2 to 2.8), thyroid nodules (HR, 6.3; 95% CI, 5.2 to 7.5), thyroid cancer (HR, 9.2; 95% CI, 6.2 to 13.7), growth hormone deficiency (HR, 5.3; 95% CI, 4.3 to 6.4), obesity (relative risk, 1.8; 95% CI, 1.7 to 2.0), and diabetes mellitus (relative risk, 1.9; 95% CI, 1.6 to 2.4). Women exposed to high-risk therapies had six-fold increased risk for premature ovarian insufficiency (P &lt; .001), and men demonstrated higher prevalence of testosterone replacement (P &lt; .001) after cyclophosphamide equivalent dose of 20 g/m(2) or greater or testicular irradiation with 20 Gy or greater. Survivors demonstrated an increased risk for all thyroid disorders and diabetes mellitus regardless of treatment exposures compared with siblings (P &lt; .001 for all).</p>

<p><strong>CONCLUSION: </strong>Endocrinopathies in survivors increased substantially over time, underscoring the need for lifelong subspecialty follow-up of those at risk.</p>

10.1200/JCO.2016.66.6545

J. Clin. Oncol.

27382091