Computer tomography-based body surface area evaluation for drug dosage: Quantitative radiology versus anthropomorphic evaluation.

The measure of body surface area (BSA) is a standard for planning optimal dosing in oncology. This index is derived from a model having questionable performances. In this study, we proposed measurement of BSA from whole body CT images (iBSA). We tested the reliability of iBSA assessments and simulated the impact of our approach on patient chemotherapy dosage planning.We first evaluated accuracy and precision of iBSA in measuring 14 phantom and 11 CT test-retest images.Secondly, we retrospectively analyzed 26 whole body PET-CT scans to evaluate inter-method variability between iBSA and the most used anthropomorphic models, notably the "Du Bois and Du Bois" model. Finally, we simulated the impact on chemotherapy dose planning of capecitabine based on iBSA.Precision and accuracy of iBSA measurement featured a standard deviation of 1.11% and a mean error of 1.53%. Inter-method variability between iBSA and "Du Bois and Du Bois" assessment featured a standard deviation of 4.11% leading to a reclassification rate of capecitabine of 32.5%.iBSA could help the oncologist in standardizing assessments for chemotherapy planning. iBSA could also be relevant for applications such as comprehensive body composition and provide a sensitive measurement for changes related to nutritional intake or other metabolism

Inter-method comparison between image-derived BSA and main anthropomorphic models.

<p>From left to right are reported inter-methods variabilities between iBSA and 1) du Bois & du Bois, 2) Mosteller, 3) Haycock, 4) Boyd and 5) Gehan & George anthropomorphic models. For each model comparison, parameters depicting variability are, from top to bottom: 1) Standard Deviation (StdDev) and 2) Bias.</p

Population of the study.

<p>Distribution of weight (horizontal) and height (vertical) of the 26 patients involved in the study.</p

Simulation scheme of re-classification rate calculation according to dose banding adjustment of capecitabine.

<p>N = 1000000 BSA samples were uniformly simulated between 1.2 and 2.5m². We assessed the ratio of patient (red circle) of different morphology that would have received a different dosage depending on the method used for BSA assessment. We used a table of standard dose according to a dose-banding protocol.</p

Qualification results of image-derived BSA.

<p>a) Accuracy: Box plot of percent relative error in computing BSA of CT phantom. 14 acquisitions of the phantom were repeated with various positions. Median error was 1.54% ranging from -3.3% to 13.06%. b) Precision: Bland Altman plot of test-retest measurement of 11 thoracic and thoracic abdominal patients from the RIDER database.</p

Inter-method comparison between image-derived BSA and Du Bois formula.

<p>a) Regression of BSA assessments between du Bois & du Bois method and imaging. Twenty-six patients’ data were considered. b) Bland Altman plot of Surface CT against du Bois & du Bois estimation. The relative difference of error reported a SD = 4.11% with a constant bias of 3.6%.</p

Image-derived BSA quality assessment.

<p>Left: Original whole body acquisition, Right: corresponding segmentation mask, Bottom: volume rendering. Two reviewers simultaneously compared original whole body scans, CT scans and segmentation masks to report if corrections were needed.</p

General anaesthetic agents do not influence persistent pain after breast cancer surgery

International audienc

Neuropathic Aspects of Persistent Postsurgical Pain: A French Multicenter Survey With a 6-Month Prospective Follow-Up

International audienc