Don Lawrence and the "k-capture" revolution

UMMS Affiliation

Department of Radiation Oncology



Document Type


Medical Subject Headings

Brachytherapy; Cesium Radioisotopes; History, 20th Century; Humans; Iodine Radioisotopes; United States


Neoplasms | Oncology


PURPOSE: The practice of brachytherapy was in steep decline in the mid-20th century, largely because of safety issues. This article explores the innovations that revitalized brachytherapy with special attention to the introduction of low-energy seeds for permanent implantation.

METHODS AND MATERIALS: Literature review; interviews; and the memos, records, and correspondence of Donald C. Lawrence.

RESULTS: Paul Harper first proposed the use of radionuclides that decay by k-capture in the 1950s. But it was the vision and tenacity of health physicist Donald Lawrence that led to the successful implementation of I-125 (in the 1960s) and Cs-131 (40 years later).

Rights and Permissions

Brachytherapy. 2010 Oct-Dec;9(4):373-81. doi: 10.1016/j.brachy.2009.07.014. Link to article on publisher's site

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Link to Article in PubMed

PubMed ID