Jean A. McDougall

Relationship between Radiation Exposure and Risk of Second Primary Cancers among Atomic Bomb Survivors

Radiation exposure is related to risk of numerous types of cancer, but relatively little is known about its effect on risk of multiple primary cancers. Using follow-up data through 2002 from 77,752 Japanese atomic bomb survivors, we identified 14,048 participants diagnosed with a first primary cancer, of whom 1,088 were diagnosed with a second primary cancer. Relationships between radiation exposure and risks of first and second primary cancers were quantified using Poisson regression. There was a similar linear dose-response relationship between radiation exposure and risks of both first and second primary solid tumors [excess relative risk (ERR)/Gy = 0.65; 95% confidence interval (CI), 0.57-0.74 and ERR/Gy = 0.56; 95% CI, 0.33-0.80, respectively] and risk of both first and second primary leukemias (ERR/Gy = 2.65; 95% CI, 1.78-3.78 and ERR/Gy = 3.65; 95% CI, 0.96-10.70, respectively). Background incidence rates were higher for second solid cancers, compared with first solid cancers, until about age 70 years for men and 80 years for women (P < 0.0001), but radiation-related ERRs did not differ between first and second primary solid cancers (P = 0.70). Radiation dose was most strongly related to risk of solid tumors that are radiation-sensitive including second primary lung, colon, female breast, thyroid, and bladder cancers. Radiation exposure confers equally high relative risks of second primary cancers as first primary cancers. Radiation is a potent carcinogen and those with substantial exposures who are diagnosed with a first primary cancer should be carefully screened for second primary cancers, particularly for cancers that are radiation-sensitive.

The Clinical and Economic Impacts of Skeletal-Related Events Among Medicare Enrollees With Prostate Cancer Metastatic to Bone

BACKGROUND Approximately 40% of men diagnosed with metastatic prostate cancer experience one or more skeletal-related events (SREs), defined as a pathological fracture, spinal cord compression, or surgery or radiotherapy to the bone. Accurate assessment of their effect on survival, health care resource utilization (HCRU), and cost may elucidate the value of interventions to prevent SREs. MATERIALS AND METHODS Men older than age 65 years with prostate cancer and bone metastasis diagnosed between 2004 and 2009 were identified from linked Surveillance Epidemiology and End Results-Medicare records. Hazard ratios (HRs) and 95% confidence intervals (CIs) for the risk for death associated with SREs were calculated by using Cox regression. HCRU and costs (in 2013 U.S. dollars) were evaluated in a propensity score-matched cohort by using Poisson regression and Kaplan-Meier sample average estimators, respectively. RESULTS Among 3,297 men with prostate cancer metastatic to bone, 40% experienced ≥1 SRE (median follow-up, 19 months). Compared with men who remained SRE-free, men with ≥1 SRE had a twofold higher risk for death (HR, 2.29; 95% CI, 2.09-2.51). Pathological fracture was associated with the highest risk for death (HR, 2.77; 95% CI, 2.38-3.23). Among men with ≥1 SRE, emergency department visits were twice as frequent (95% CI, 1.77-2.28) and hospitalizations were nearly four times as frequent (95% CI, 3.20-4.40). The attributable cost of ≥1 SRE was

Timing of Menarche and First Birth in Relation to Risk of Breast Cancer in A-Bomb Survivors

21,191 (≥1 SRE:

Trends in Distant-Stage Breast, Colorectal, and Prostate Cancer Incidence Rates from 1992 to 2004: Potential Influences of Screening and Hormonal Factors

72,454 [95% CI,

Evaluation of seasonality in the diagnosis of acute myeloid leukaemia among adults in the United States, 1992-2008.

67,362-

Abstract A81: Relationship between out-of-pocket cost and use of tyrosine kinase inhibitors for the treatment of chronic myeloid leukemia

76,958]; SRE-free:

Indian Health Service Care System and Cancer Stage in American Indians and Alaska Natives

51,263 [95% CI,

Abstract P3-07-34: Breast cancer pathologic subtype and fetal microchimerism

45,439-

Abstract PR8: Socioeconomic determinants of the receipt of guideline-concordant breast cancer treatment

56,100]). CONCLUSION Among men with prostate cancer metastatic to bone, experiencing ≥1 SRE is associated with poorer survival, increased HCRU, and increased costs. These negative effects emphasize the importance of SRE prevention in this population.

Racial and ethnic disparities in cervical cancer incidence rates in the United States, 1992−2003

Background: The length of the interval between age at menarche and age at first birth is positively associated with breast cancer risk. We examined the risk of breast cancer in atomic bomb survivors to investigate whether women exposed to radiation between menarche and first birth had a higher risk of radiogenic breast cancer than women exposed at the same age but outside this interval. Methods: Women (n = 30,113) were classified into three reproductive status at the time of the bombings (ATB) categories (premenarche, between menarche and first birth, or after first birth). Poisson regression was used to test the primary hypothesis. Results: When the background rate of breast cancer was taken to depend on city, age ATB, and attained age only, the radiation-related excess relative risk (ERR) varied significantly among the three categories (P = 0.049). However, after controlling for significant heterogeneity in the baseline risk of breast cancer between reproductive status ATB groups (P < 0.001), no significant heterogeneity (P = 0.88) was observed in the ERR, with an ERR per Gy of 1.36 [95% confidence interval (CI), 0.54-2.75] for women exposed between menarche and first birth ATB, and 1.07 (95% CI, 0.22-3.62) and 1.53 (95% CI, 0.63-2.90) for those exposed premenarche or after first birth, respectively. Conclusions: The radiation-associated risk of breast cancer does not vary significantly by reproductive status ATB. Impact: It is possible that radiation exerts similar carcinogenic effects on the breast regardless of its stage of differentiation, or that the differences in radiosensitivity are too small to be detected in this cohort. Cancer Epidemiol Biomarkers Prev; 19(7); 1746–54. ©2010 AACR.