TY - JOUR T1 - Trends in Subcutaneous Tumour Height and Impact on Measurement Accuracy JF - bioRxiv DO - 10.1101/2022.09.29.510123 SP - 2022.09.29.510123 AU - Daniel Brough AU - Hope Amos AU - Karl Turley AU - Jake Murkin Y1 - 2022/01/01 UR - http://biorxiv.org/content/early/2022/09/30/2022.09.29.510123.abstract N2 - Tumour volume is typically calculated using only length and width measurements, using width as a proxy for height in a 1:1 ratio. When tracking tumour growth over time, important morphological information and measurement accuracy is lost by ignoring height, which we show is a unique variable. Lengths, widths, and heights of 9,522 subcutaneous tumours in mice were measured using 3D and thermal imaging. The average width:height ratio was found to be 1:3 proving that using width as a proxy for height overestimates tumour volume. Comparing volumes calculated with and without tumour height to the true volumes of excised tumours indeed showed that using the volume formula including height produced volumes 36X more accurate. Monitoring the width:height relationship (prominence) across tumour growth curves indicated that prominence varied, and that height could change independent of width. Twelve cell lines were investigated individually; the scale of tumour prominence was cell line-dependent with relatively less prominent tumours (MC38, BL2, LL/2) and more prominent tumours (RENCA, HCT116) detected. Prominence trends across the growth cycle were also dependent on cell line; prominence was correlated with tumour growth in some cell lines (4T1, CT26, LNCaP), but not others (MC38, TC-1, LL/2). When pooled, invasive cell lines produced tumours that were significantly less prominent at volumes >1200mm3 compared to non-invasive cell lines (P<0.001). Modelling was used to show the impact of the increased accuracy gained by including height in volume calculations on several efficacy study outcomes. Variations in accuracy contribute to experimental variation and irreproducibility of data, therefore we strongly advise researchers to measure height to improve accuracy in tumour studies.Competing Interest StatementBioVolume Ltd (an operating company of Fuel3D) is developing the BioVolume unit and software and claims financial competing interests on the product. There are specific patents granted and filed for this technology or any part of it. BioVolume Ltd provided support in the form of salaries for authors but did not have any additional role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript. In vivo work and all measurements were carried out by BioVolume users who were not employed by BioVolume Ltd and who did not receive financial compensation. 3D-TI3D and thermal imagingANOVAAnalysis of varianceCTComputerised tomographyGAMGeneralised additive modelLWHVolume formula using length, width, and heightLWWVolume formula using length and widthMRIMagnetic resonance imagingTGITumour growth inhibition ER -