In Figure 15., the linear regression equation for the best-fit line for VPleth values on the y-axis along with VC and VS values would be approximately y x, or y 1.00x + 0.00. Tumor growth was investigated without therapy and with antiangiogenic therapy (using bevacizumab [15]). recurrent glioblastoma (rGBM) [36]) as a first or second line treatment, usually in combination with chemo- or immunotherapy. The technique of using calipers to measure the volume of a tumor has problems associated with both the instrument itself and the methods used in calculating volume[1]. Figure 7. https://doi.org/10.1371/journal.pone.0142190.g001. Although the low dose bevacizumab therapy is well known in the literature, we found no article (in the English literature) regarding very low dose and quasi-continuous bevacizumab therapy, as used in our study. where v is tumor volume [mm3] and m is tumor mass [g]. official website and that any information you provide is encrypted No animals were sacrificed before the experimental endpoint. produced by the TumorImager-2TM so that the animal is aligned under the mask each time similarly to the previous scan. Tumor volume was measured with digital caliper. Bevacizumab is an exogenous inhibitor which inhibits the biological activity of human VEGF. Gullino, P.M., Pettigrew, H.M. & Grantham, F.H. Starting with f = 1, we have investigated the goodness of the fitting, using an iterative method. Tumor volume in subcutaneous mouse xenografts measured by microCT is more accurate and reproducible than determined by 18 F-FDG-microPET or external caliper. Small MRI measurements were done in the Preclinical Imaging Center of Gedeon Richter Plc. r>12TzPn 4x PUj50"pJ{{>y{.mn|Cvz{PP5x kH:5:YM.gn?c[J8oQWkR_!X/C@6P@WT=gO5Sn>om}&SI cyT>E"TnkhSju>~yVOm^C~0__ww@ y[xQr33?6O~hZcR{{u]=O5T. Tumor measurement by TumorImager-2TM. contracts here. The tumor number, from one to ten, is shown against the percent error. Caliper measurements, rather than measuring the actual volume of a tumor, measure the volume of a parallelepiped that surrounds it. A smaller diameter mask will help to position the tumor in the center of the scan, but it will not alter this effect. Lee, J., Koh, D. & Ong, C.N. Tumor segmentation by TumorImager-2TM. Correlation was investigated with Pearsons rank correlation test (Pearsons R) and coefficient of determination (R2). We compared tumor volumes estimated in vivo by BLI and FLI, to those calculated by caliper measurements and found a good correlation between these two techniques (Figure 4). A patented algorithm running in the TumorManagerTM program calculates the tumor volume by creating a 3D surface map of the tumor (red-colored surface in Figure 12.). obtained using vernier calipers (c.c) Vol. The cause of death was tumor toxicity; however, none of the clinical criteria for euthanasia could be observed at these animals. Kobayashy, T. et al. This problem can be explained by our observation, namely tumors which were grown without therapy have more symmetric and solid closed shape, in contrast to tumors which were grown under antiangiogenic therapy. Kim DK, Synn CB, Yang SM, Kang S, Baek S, Oh SW, Lee GJ, Kang HW, Lee YS, Park JS, Kim JH, Byeon Y, Kim YS, Lee DJ, Kim HW, Park JD, Lee SS, Lee JY, Lee JB, Kim CG, Hong MH, Lim SM, Kim HR, Pyo KH, Cho BC. Breast cancer measurements with magnetic resonance imaging, ultrasonography, and mammography. Repetitive non-typhoidal Salmonella exposure is an environmental risk factor for colon cancer and tumor growth. Radiology 157, 54 (1985). Consequences are manifold. 19, 6170 (1989). Measure the three dimensions of peanut M&M's, serving as our similar-sized tumor surrogates, using vernier calipers. The article discusses two results. Department of Control Engineering and Information Technology, Budapest University of Technology and Economics, Budapest, Hungary, Affiliation A graph depicting tumor volume in mm3, as measured by a caliper compared to its actual volume, vs. days. Pritt, B., Ashikaga, T., Oppenheimer, R.G. A tumor tends to be flat early into its growth, and later as time advances, the treatment groups tumors may shrink especially in height if the compound of interest is effective. In Phase I, 12 mice were implanted with C38 colon adenocarcinoma. 41, 16901694 (1981). Figure 17. Another approach is to utilize the scan images (Figure 14.) calipers and Water Displacement methods Tumor mimicking objects Vol. A diagram of an ellipsoid, with the derivations of the variables needed to calculate its volume. Later in a study, when a tumor grows into larger masses, the shape of the tumor can differ greatly from an ellipsoid, as shown in Figure 7. From the abovementioned methods, the consequence is that the promising new direction in tumor volume evaluation is the dimension reduction, namely to find a statistical constant which can replace the need of measuring the tumor height. We have investigated the relationship between MRI-measured tumor volume and vascularization area (Phase III/3 case and control groups, 23rd (final) day of the experiment) but no significant correlation was found (same results were published in the case of Phase I [26] and Phase III/2 [23]). The significant difference between quasi-continuous therapy (Phase III/3 case group) and tumor growth without treatment (Phase I) was proved with statistical analysis as well. & Russo, I.H. To obtain This means that continuous, low dose antiangiogenic factor (VEGF) administration is needed. Wrote the paper: JS ZS PK LK. The height and topography of the tumor is not taken into account in a caliper measurement. The volume calculation algorithm relies on the surface interpolated based on the surrounding healthy tissue. (2), Whilst studies have shown that tumors can be better estimated with ellipsoid shape than using Eq 1, calculating the volume of an ellipsoid requires the knowledge of the third parameter. In both cases, three groups were compared in the experiments. Thus, caliper-based measurements, using the formula , are most accurate in real life for tumors in which height roughly equals width but prove less accurate as height becomes more unequal to width, as is the case with almost all real tumors. Estimation of rat mammary tumor volume using caliper and ultrasonography measurements. https://doi.org/10.1371/journal.pone.0142190.g007. Hedrich, H.J. Girit, I.C., Jure-Kunkel, M. & McIntyre, K.W. The authors declare no competing financial interests. We have examined C38 mouse colon adenocarcinoma and HT-29 human colorectal adenocarcinoma. & trukelj, B. N-methylnitrosourea induced breast cancer in rat, the histopathology of the resulting tumours and its drawbacks as a model. N-nitrosomethylurea as mammary gland carcinogen in rats. In this study, the authors measured dimensions of rat mammary tumors using a caliper and using real-time . Mice were humanely sacrificed using cervical dislocation. Tumor growth inhibition rate (%); can be calculated using the following formula: = (Vc 1 -Vt 1 )/ (Vc 0 -Vt 0) X 100. where, Vc 1 is the mean tumor volume in the control group at the time of tumor . ), the more correlated a given group (scanner or caliper estimations) is to the black line (r2 = 1), the more accurate the tumor volume measurements are. Tumor volume (and the third diameter) has to be approximated, assuming a certain shape for the tumor. The second result which is discussed in the article is comparison of the effectiveness of bevacizumab administration in the case of protocol-based and quasi-continuous therapies. Current standard technique for volume determination of subcutaneously xenografted tumors in vivo is by external caliper where tumor volume is calculated by use of the modified ellipsoid formula 1/2(Length Width 2)[1,2]. here. The https:// ensures that you are connecting to the A tumor image, its 3D shape and all geometrical data are automatically calculated and stored. How the device is positioned over the tumor will not influence the result. Also, at beginning of the tumor growth when the tumor is invisible or when a tumor shrinks due to the effectiveness of the drug, in order to measure the volume of such an invisible tumor, it is a general practice to palpate the tumor area to reveal some mass to measure. Consequently, when tumor mass data is unavailable (during the experiment), tumor volume value can be validated with MRI; in that way outlier data points (which were calculated using the two-dimensional mathematical model) can be filtered out. There are no further patents, products in development or marketed products to declare. https://doi.org/10.1371/journal.pone.0142190.g008. The closer the slope of a line on this graph is to 1 and the y-intercept to 0, the closer the measurements of the device it represents are to the exact values of the tumors volumes. An average penny has a diameter of 19 mm and a height of 1.27 mm, yielding a volume of 360.1 mm3. A two-dimensional mathematical model was created from the experimental results of BALB/c mice with KHJJ tumor line [25]: Even though, almost 95% of the researchers who have been doing these measurements for decades, as a company who developed an accurate and faster device for such measurements, we realized that most of these people do not know the mathematical nature of the formula they use to calculate the tumor volumes measured by calipers. Position of the mouse was fixed to minimize the movement of the animal. Mol. Tukeys HSD test resuled in significant difference between case1 and case2 groups (p = 0.038). M}{Gt{zj|&cXx[k?CZ ~AjTxMr0 '~ix$mj/)9?$ t-o6MkVXs's}^E6-^_Yrv#w&r7w@WsQs]#G g$Cn. The parameters V m = 83 mm 3, = 0.84 and = 0.21 from the literature were used [].. For \( {y}_i^j \) eqs. In this phase, 5 immunocompetent mice in control group, and 9 immunocompetent mice in case group were used. A direct and real 3D volume of the xenograft will then be calculated. YH29407 with anti-PD-1 ameliorates anti-tumor effects. https://doi.org/10.1371/journal.pone.0142190, Editor: Francesco Bertolini, by US (c.c) Vol. The tumor burden is evaluated by volume calculation using caliper measurement. Unmeasured part of the tumor for caliper, Figure 11. Better results can be obtained by proper handling of the mice. The problems with tumor volume measurements by calipers 3.1 Tumor growth: Height is not equal to the width of the tumor . Each day before the administration, the mice' body weight and tumor volume were measured and recorded. Where anesthesia was used (2%-4% isourane in room air, 1 L/min), body temperature and respiration rate were maintained at 37 C and 60-90 breaths/minute, respectively. Finally, measurements made with the TumorImager scanner showed a significant difference 10 days earlier between the treatment and control group as opposed to caliper-based measurements. It means that a mouse of the case group received 1.11 g bevacizumab (with 45 l 0.9% NaCl solution) every day from the 3rd day for 20 days. https://doi.org/10.1371/journal.pone.0142190.g006. In one trial, 208 tumors were measured, and 98.94% of those tumors exhibited much smaller heights than widths. To compare the effectiveness of the different investigated treatment methods, statistical analysis was used. In the meantime, to ensure continued support, we are displaying the site without styles Berg, W.A. Russo, J. For more information about PLOS Subject Areas, click Description of Lesions. Determining tumor volume is a useful and quantitative way to monitor tumor progression. Typical side-effects and adverse events are arterial and venous thromboembolic events, bleeding, hypertension, febrile neutropenia, infections, proteinuria, mucositis, and hand-foot syndrome. Finally, it finds the volume between these two surfaces and sets this to be the volume of the tumor (shaded red region in Figure 11, red region in Figure 14 below). Experimentally induced mammary tumors in rats. Epub 2013 Jul 11. Tumor volume was calculated by the modified ellipsoidal formula: V = (Length Width 2) . e0142190. In the experiment 9.4 Tesla field strength Varian small-animal MRI was used. Bevacizumab (Avastin) [1] is an exogenous inhibitor, which inhibits the biological activity of human VEGF [2]. Levenes test showed that the sample variances are equal (p = 0.108). 01 July 2022. One can find datasets in Table 3. PLOS ONE promises fair, rigorous peer review, In addition, the root mean square, R2 values under the linear regression equations in Figure 15. symbolize the precision of the data. A quiet and modestly T2-weighted spin-echo scan was acquired at 4.7T (TE = 15 msec, TR = 1100 msec, 0.5 mm isotropic . Tumor volume determined by microCT, 18 F-FDG-PET and external caliper Tumor volume measured by microCT, PET and caliper all correlated (P < 0.001) with reference volume (figure 1).MicroCT versus reference volume (n = 20) had the best fit of line y = 1.01 0.04x - 6.1 6.3 (R 2 = 0.97; p < 0.001). Result of Phase III/2 was that the effectiveness of the small amount of quasi-continuous dosage is comparable with the effectiveness of one large dose [23], however this result is only based on caliper-measured data. However, most serious questions are: for how long and continuous or not? Thus, caliper-based measurements are less accurate the more the height of the stack deviates from its width. In this way, the targeted therapy can be used in a much more individualized form. After fixing in methanol, rat anti-mouse CD31 antibody (1:50, 550274 BD PHARMINGEN) was applied as primer antibody, and FITC conjugated anti-rat CD31 antibody (1:100, Jackson Immunoresearch, 712-095-150) was applied on the slides as secondary antibody. We are sorry, but there is no personal subscription option available for your country. Exer. The tumor can be more and sometimes less visible or popped up from under the skin. Although there are studies which confirme that bevacizumab is as effective as the murine anti-VEGF-R2 antibody (DC101) in mouse models ([27, 28]), we extended our experiments and performed Phase IV, where immunocompromized (SCID) mice were used with human colorectal adenocarcinoma (HT-29) xenografts. The scan images obtained are only for the external surface of the tumor. Value of prostate volume measurement using transabdominal ultrasonography for the improvement of prostate-specific antigen-based cancer detection. CAS Mice in Phase III/3 control and case groups, and mice in Phase IV case1 and case2 groups received bevacizumab. Since, the assumptions made to measure a 3D object with 2D measurements, the error due to the geometrical assumption are larger than the errors due to handling of the animal causing deformation of the tumor, and this aspect, in general, is ignored. Cancer Res. For this dataset, linear curve fitting was carried out (fitted linear curve) to find the mathematical relationship between MRI-measured tumor volume and tumor mass. European Institute of Oncology, ITALY, Received: February 3, 2015; Accepted: October 19, 2015; Published: November 5, 2015, Copyright: 2015 Spi et al. All surgery and sacrifice were performed under sodium pentobarbital anaesthesia (Nembutal, 70 mg/kg). 2009, 18 (2009). The authors say special thanks to Katalin Dezs MD. Caliper instructions are provided as well as an introduction to ellipsoids. The R2 value for the scanner is 0.99, as opposed to that for the caliper being 0.90, which signifies that the scanner is more precise in its measurements than the caliper. 37, 331337 (2011). J. Urol. We have found that mice which have received therapy had tumor with irregular, and in several cases berry-shaped structure, especially when reaching large volume. The mathematical relationship between MRI-measured tumor volume and mass was investigated to estimate accurate tumor volume using caliper-measured data. & Lin, C.A. Kim HB, Zeng CH, Kim Y, Jeong S, Kim SH, Kang JM, Park Y, Won DS, Kim JW, Ryu DS, Lim B, Park JH. Our hypothesis is that the effectiveness of a lower dosage with a quasi-continuous therapy can be comparable with the protocol therapy. It was on the 10th day, since HT-29 colorectal adenocarcinoma grows slower in mice than C38 colon adenocarcinoma. VC refers to tumor volume values calculated through the formula VT = 0.5 L W2, and VCH refers to those through the formula VT = 0.5 L W H. VS refers to measurements taken by the scanner, and % Inc. refers to the percent increase between VS and VCH. We found out that due to this unmeasured part, the dissected tumor volumes were about 6% larger than the scan results. Click through the PLOS taxonomy to find articles in your field. This paper reviews the standard technique for tumour volume assessment, calliper measurements, by conducting a statistical review of a large dataset consisting of 2,500 tumour volume measurements from 1,600 mice by multiple operators across 6 mouse strains and 20 tumour models. CA Cancer J. Clin. Figure 15. (8) This estimation has the same disadvantage as ellipsoid estimation, i.e. Statistical evaluations of agreement between two methods for measuring a quantitative variable. Using a caliper, growth of the tumor in height is not measured as only width and length changes will affect the calculated volume. This is the formula most used in research and industry. A two-dimensional mathematical model was applied for tumor volume evaluation, and tumor- and therapy-specific constants were calculated for the three different groups. ISSN 0093-7355 (print). Google Scholar. For the sake of convenience, establishments will simplify and H. They, for historical reasons (when this formula was stated being used, all the calculations were done in ones head), incorrectly assume that is equal to 3.0 and that the height of a tumor (H) is equal to its width (W). Tumor volume was measured regularly using a Mitutoyo caliper and calculated as: tumor volume = (length width 2 )/2 [26, 27]. On Day 14, when the tumor volume reached ~500 mm 3, the mice were . Secondly, the aspect of side-effects are not inconsiderable. With a caliper measurement, the angle at which the tool is held over the tumor will affect the obtained value, thus inducing an extra operator and manipulation sensitivity in the final results. Compute the volume assuming perfect ellipsoids. Tumor volume measurement cannot happen right after tumor implantation. Notice that the red dots are generally underestimations, while the blue squares are generally overestimations; the former is because of the unmeasured part of the tumor, as discussed in Section 3.5, and the fact that tumors tend to grow under the surface of the skin rather than above it in their early stages of development, and the latter is because of the inherent overestimation in the industry-standard caliper-based formula. 22, 921929 (2003). No, Is the Subject Area "Cancer treatment" applicable to this article? Figure 4. Discover a faster, simpler path to publishing in a high-quality journal. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. The first column shows the tumor values which were calculated using the two-dimensional mathematical model; the second column represents the protocol-based tumor volumes. For small tumors, the error is about 7%, while for large tumors it is 27%.[3]. We monitored the vital parameters of 4 immunocompetent mice, and there was no serious toxic side-effect or lethality regarding to the usage of bevacizumab. Measurements with small animal MRI were done on the 4th, 8th, 11th, 15th, 18th and 23rd days of the experiment in Phase III/3. Affiliation Treat. 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