Use this URL to cite or link to this record in EThOS: https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.823282
Title: Impact of 3D image based dosimetry on treatment planning in Peptide Receptor Radionuclide Therapy (PRRT)
Author: Page, Emma
ISNI:       0000 0005 0290 596X
Awarding Body: University of Manchester
Current Institution: University of Manchester
Date of Award: 2020
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Abstract:
Red marrow is an organ at risk for Peptide Receptor Radionuclide Therapy (PRRT) used to treat Neuroendocrine Cancer. Excessive red marrow irradiation causes haematological toxicity and potentially Myleodysplastic Syndrome and Acute Mye - loid Leukemia. Red marrow radiation exposure is quantified in terms of absorbed dose using internal dosimetry. Absorbed dose estimation enables treatment planning of PRRT therapies by ensuring that red marrow absorbed dose is within recommended dose limits to avoid toxicity. This thesis compared traditional blood based methods of red marrow dosimetry to newer SPECT-CT image based methods for 15 PRRT patients, to assess the impact of method choice on absorbed dose magnitude and the ability to predict toxicity after PRRT. An attempt was made to optimise the more flexible image based method by investigating the effect of different approaches to SPECT partial volume correction (PVC) and red marrow mass estimation. Ability to predict toxicity was compared for patients who had previous treatments which could have damaged red marrow function, and those which had not. Optimised image based techniques using appropriate SPECT PVC and image based patient specific red marrow mass estimates, produced significantly higher red marrow doses than blood based methods (a factor of 2.2 to 3.8 mean dose increase for the cohort; individual patient dose increase could be as high as a factor of 7.1). The impact on treatment planning would be a reduction in the number of PRRT treatments a patient could have before reaching the red marrow dose limit if the image based method is used. Patients without prior marrow damage produced the strongest dose response relationships, and this occurred for the optimised image based methods (Rw ranging from -0.83 to -0.85, p<0.05). Equivalent blood based methods failed to produced significant correlations for either cohort.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID: uk.bl.ethos.823282  DOI: Not available
Keywords: Internal dosimetry ; Red marrow ; Treatment planning ; SPECT - CT
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