Dataset Information

Estimating cancer risk from ^99mTc pyrophosphate imaging for transthyretin cardiac amyloidosis.

ABSTRACT:

Background

Increasing recognition that transthyretin cardiac amyloidosis (ATTR-CA) is much more common than previously appreciated and the emergence of novel disease-modifying therapeutic agents have led to a paradigm shift in which ATTR-CA screening is considered in high-risk populations, such as patients with heart failure with preserved ejection fraction (HFpEF) or aortic stenosis. Radiation risk from ^99mTc-pyrophosphate (^99mTc-PYP) scintigraphy, a test with very high sensitivity and specificity for ATTR-CA, has not been previously determined.

Methods and results

Radiation doses to individual organs from ^99mTc-PYP were estimated using models developed by the Medical Internal Radiation Dose Committee and the International Commission on Radiological Protection. Excess future cancer risks were estimated from organ doses, using risk projection models developed by the National Academies and extended by the National Cancer Institute. Excess future risks were estimated for men and women aged 40-80 and compared to total (excess plus baseline) future risks. All-organ excess cancer risks (90% uncertainty intervals) ranged from 5.88 (2.45,11.4) to 12.2 (4.11,26.0) cases per 100,000 patients undergoing ^99mTc-PYP testing, were similar for men and women, and decreased with increasing age at testing. Cancer risks were highest to the urinary bladder, and bladder risk varied nearly twofold depending on which model was used. Excess ^99mTc-PYP-related cancers constituted?ConclusionVery low cancer risks associated with ^99mTc-PYP testing suggest a favorable benefit-risk profile for ^99mTc-PYP as a screening test for ATTR-CA in high-risk populations, such as such as patients with HFpEF or aortic stenosis.

SUBMITTER: Einstein AJ

PROVIDER: S-EPMC6269210 | biostudies-literature | 2020 Feb

REPOSITORIES: biostudies-literature

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Estimating cancer risk from <sup>99m</sup>Tc pyrophosphate imaging for transthyretin cardiac amyloidosis.

Einstein Andrew J AJ Shuryak Igor I Castaño Adam A Mintz Akiva A Maurer Mathew S MS Bokhari Sabahat S

Journal of nuclear cardiology : official publication of the American Society of Nuclear Cardiology 20180530 1

<h4>Background</h4>Increasing recognition that transthyretin cardiac amyloidosis (ATTR-CA) is much more common than previously appreciated and the emergence of novel disease-modifying therapeutic agents have led to a paradigm shift in which ATTR-CA screening is considered in high-risk populations, such as patients with heart failure with preserved ejection fraction (HFpEF) or aortic stenosis. Radiation risk from <sup>99m</sup>Tc-pyrophosphate (<sup>99m</sup>Tc-PYP) scintigraphy, a test with very ...[more]

PMID: 29850972

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