The risk of developing a second cancer after receiving craniospinal proton irradiation

The purpose of this work was to compare the risk of developing a second cancer after craniospinal irradiation using photon versus proton radiotherapy by means of simulation studies designed to account for the effects of neutron exposures. Craniospinal irradiation of a male phantom was calculated for passively-scattered and scanned-beam proton treatment units. Organ doses were estimated from treatment plans; for the proton treatments, the amount of stray radiation was calculated separately using the Monte Carlo method. The organ doses were converted to risk of cancer incidence using a standard formalism developed for radiation protection purposes. The total lifetime risk of second cancer due exclusively to stray radiation was 1.5% for the passively scattered treatment versus 0.8% for the scanned proton beam treatment. Taking into account the therapeutic and stray radiation fields, the risk of second cancer from intensity-modulated radiation therapy and conventional radiotherapy photon treatments were 7 and 12 times higher than the risk associated with scanned-beam proton therapy, respectively, and 6 and 11 times higher than with passively scattered proton therapy, respectively. Simulations revealed that both passively scattered and scanned-beam proton therapies confer significantly lower risks of second cancers than 6 MV conventional and intensity-modulated photon therapies. © 2009 Institute of Physics and Engineering in Medicine

Ocular late effects in childhood and adolescent cancer survivors: A report from the childhood cancer survivor study

Introduction—Approximately 80% of children currently survive 5 years following diagnosis of their cancer. Studies based on limited data have implicated certain cancer therapies in the development of ocular sequelae in these survivors. Procedure—The Childhood Cancer Survivor Study (CCSS) is a retrospective cohort study investigating health outcomes of 5+ year survivors diagnosed and treated between 1970 and 1986 compared to a sibling cohort. The baseline questionnaire included questions about the first occurrence of 6 ocular conditions. Relative risks (RR) and 95% confidence intervals (CI) were calculated from responses of 14,362 survivors and 3,901 siblings. Results—Five or more years from the diagnosis, survivors were at increased risk of cataracts (RR:10.8; 95% CI: 6.2–18.9), glaucoma (RR: 2.5; 95% CI: 1.1–5.7), legal blindness (RR: 2.6; 95% CI: 1.7–4.0), double vision (RR:4.1; 95% CI: 2.7–6.1), and dry eyes (RR: 1.9; 95% CI: 1.6–2.4), when compared to siblings. Dose of radiation to the eye was significantly associated with risk of cataracts, legal blindness, double vision, and dry eyes, in a dose-dependent fashion. Risk of cataracts were also associated with radiation 3000+ cGy to the posterior fossa (RR: 8.4; 95% CI: 5.0–14.3), temporal lobe (RR: 9.4; 95% CI: 5.6–15.6), and exposure to prednisone (RR:2.3; 95% CI:.1.6–3.4) Conclusions—Childhood cancer survivors are at risk of developing late occurring ocular complications, with exposure to glucocorticoids and cranial radiation being important determinants of increased risk. Long-term follow-up is needed to evaluate potential progression of ocular deficits and impact on quality of life

Cardiac outcomes in a cohort of adult survivors of childhood and adolescent cancer: retrospective analysis of the Childhood Cancer Survivor Study cohort

Objectives To assess the incidence of and risks for congestive heart failure, myocardial infarction, pericardial disease, and valvular abnormalities among adult survivors of childhood and adolescent cancers

Thyroid nodularity after childhood irradiation for lymphoid hyperplasia: a comparison of questionnaire and clinical findings

Ionizing radiation is a well-established cause of thyroid cancer and modularity, however, important questions relating to the magnitude of the risk following low-dose medical exposures remain unresolved. To address these issues, we conducted a follow-up study of 1590 individuals treated between 1938 and 1969 with X-rays for childhood lymphoid hyperplasia (av. thyroid DOSE = 24 cGy) and 1499 individuals treated with surgery only. Thyroid nodularity was determined from self-administered questionnaires completed by 1195 irradiated and 1063 surgically-treated subjects and from clinical examinations of 602 irradiated and 457 non-irradiated subjects. A much higher relative risk (RR) for radiation-induced thyroid nodules was estimated from the questionnaire than from the clinical examination data, 15.8 and 2.7, respectively. (The corresponding estimates of excess RR per cGy were 64 and 7%). Analysis of the examination data revealed a strong dose-response relationship, similar excess RR/cGy for males and females, and an inverse relationship with age at exposure. Although the thyroid gland is one of the most sensitive organs to the neoplastic effects of radiation, the radiation-induced risk of thyroid nodularity reported from questionnaire studies may over-estimate the true risk.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/28887/1/0000723.pd

Tumors in the contralateral breast following radiation therapy for breast cancer

The proportional distribution of independent malignant tumors in the contralateral breast following treatment for breast cancer was investigated to assess the influence of scattered radiation as a cause of these tumors. In a population of 172 patients the proportion of contralateral tumors in each quadrant and the center (the nipple-areolar complex) was compared with the expected, or natural, distribution found in the general population, in the absence of radiation. The observed/expected ratio for contralateral tumors was 1.43 for the upper-inner quadrant; 0.97, lower-inner quadrant; 1.51, center; 0.76, upper-outer quadrant; and 0.64, lower-outer quadrant. In each quadrant, except the lower-inner, the observed/expected ratio differed from 1.00 with statistical significance at the 5% level (one-tail). The same analysis, stratified by age and menopausal status, showed a similar shift of tumors, with more than expected in the inner quadrants and center and less than expected in the outer quadrants, although the results did not show statistical significance at the 5% level for all strata. For each patient the mean absorbed radiation dose for each quadrant and center of the breast was estimated, based on measurements in a tissue-equivalent phantom. Among patients the doses ranged from 0.5 to 8 Gy; within individuals, doses to the inner quadrants typically were a factor of three times higher than doses to the outer quadrants. The results suggest that radiation may be a risk factor for contralateral breast tumors and warrants further investigation

Galatians 6:8

RIT PSIMAR Official Student Publication of the ROCHESTER ATHENAEUM AND MECHANICS INSTITUTE Editor-in-Chief—Rosemary Young, Associate Editor—Harry Silverman, Business Manager—Jane Moak, Secretary—Shirley Manhart, Circulation—Douglas Smith, Photographers—R. Kentos, R. Luther, E. Keeling, Advertising—Elizabeth North, Society—Rose Latin, Production—Wm. Jones, H. Maue, Reporters—Ruth Kumpel, Mary O'Dell, Bernyce Stovall, Ninfa Vitale, Ruth Wallace, Muriel Watkin