Stretching of the skin around the tumor of the mouse will cause an under-estimate of the tumor volume since the tumor is pressed into the body (see Figure 13. below). 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 defined shape of an actual tumor (red) and the shape measured by a caliper (blue box). 54, 401414 (1975). To compare more than two samples, ANOVA test was applied. Table 1. 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.). Notice that the caliper-based measurements have a larger standard deviation. These model-based protocols can be more effective than the current ones, since they provide individual treatment for the patients. here. Radiology 157, 54 (1985). We have found in our previous study [32] that measurements without contrast agents resulted in high quality images, where tumor can be circumscribed precisely, thus the usage of contrast is unnecessary. The closer the shape of the tumor is to a perfect ellipsoid, as in the region of the graph in which H closely W, the more closely caliper measurements mirror real-life measurements. Preclinical evaluation of LU 79553: a novel bis-naphthalimide with potent antitumor activity. In Phase IV, case1 group members received 200 g bevacizumab (with 200 l 0.9% NaCl solution) in one dose intraperitoneally on the 8th day. J. Urol. Mammary tumors similar to those observed in women can be induced in rats by intraperitoneal administration of N-methyl-N-nitrosourea. The post hoc test resulted in the following. We have examined C38 mouse colon adenocarcinoma and HT-29 human colorectal adenocarcinoma. Google Scholar. Med. by Mammog raphy (c.c) . Figure 1. Faustino-Rocha AI, Gama A, Oliveira PA, Alvarado A, Fidalgo-Gonalves L, Ferreira R, Ginja M. Faustino-Rocha AI, Silva A, Gabriel J, Teixeira-Guedes CI, Lopes C, Gil da Costa R, Gama A, Ferreira R, Oliveira PA, Ginja M. Biomed Pharmacother. Cells should be suspended in a volume so that 300 l contains required number of cells per injection. Mol. The size of maximum tumor volumes observed in our study fulfills the requirements of Hungarian animal experimental research protocol. Figure 18. No, Is the Subject Area "Mouse models" applicable to this article? . In each case the reference value is the MRI-measured tumor volume. We have found that there is significant difference between the means of the samples (p = 0.002, using 0.05 level of significance). A diagram of an ellipsoid, with the derivations of the variables needed to calculate its volume. Substituting tumor mass values which were measured in Phase I into Eq 8, the corresponding tumor volume values can be evaluated (one can find numerical results in Table 2 Tumor volume MRI column; and graphical results in Fig 6). Several studies have investigated the effectiveness of bevacizumab therapy according to different cancer types but these days there is an intense debate on its utility. The effectiveness strongly depends on the administration, and a drug which is effective on a molecular level can be applied in a less effective way because of the incorrectly chosen administration. Federal government websites often end in .gov or .mil. In one trial, 208 tumors were measured, and 98.94% of those tumors exhibited much smaller heights than widths. <> stream Mice were euthanized by CO2 inhalation if tumors contributed to a gain of >20% in body weight compared to controls at the same time point. volume42,pages 217224 (2013)Cite this article. Tumor volume measurement cannot happen right after tumor implantation. Determining tumor volume is a useful and quantitative way to monitor tumor progression. Similarly, Zhang et al. 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]). Levenes test showed that the sample variances are equal (p = 0.108). Position of the mouse was fixed to minimize the movement of the animal. Influence of breast cancer histology on the relationship between ultrasound and pathology tumor size measurements. In a study done in England, the researchers at the end of their experiment, dissected tumors and measured their weight with a precise balance, and used these weight values of the tumors to compare results of the caliper and the scanner measurements. Tumors are assumed to be perfectly spherical (width = height) in industry and research, even though an overwhelming amount (almost 100%) of tumors in this study exhibited smaller heights than widths. Because the industrys caliper-based formula allows for these inclusions in nonexistent volumes more often than not, it yields inaccurate measurements, which can confuse. & Moon, R.C. In Phase III/3, case group members received one-tenth dose of control dose intraperitoneally spread over 18 days. In our study, we applied a two-dimensional mathematical model and determined the corresponding tumor- and therapy-specific constants in the three investigated cases (C38 colon adenocarcinoma growth without therapy, C38 colon adenocarcinoma growth with protocol-based bevacizumab therapy and C38 colon adenocarcinoma growth with quasi-continuous bevacizumab therapy). Significance of rat mammary tumors for human risk assessment. This concept can easily be understood by a simple thought experiment: the volume of a stack of pennies (Figure 4.). The problems with tumor volume measurements by calipers 3.1 Tumor growth: Height is not equal to the width of the tumor . The reason for choosing this type of administration was as follows: a) we wanted to use a daily dose in order to investigate the biological effect of frequent impulse-like control signal for the future controller design; b) we wanted to examine such a low dose which has practically no side-effect but presumably is still effective. Autopsy revealed large metastasis in the lung, this is the suspected cause of the death. These images were applied to calculate vascularization area by using ImageJ (NIH, USA) [33] software (Fig 4). The effectiveness of the quasi-continuous (daily) 1/180 dosage (1.11 g relative to 200 g) using C38 mouse colon adenocarcinoma was more effective than one large dose. 2023 Jan 20;42(1):25. doi: 10.1186/s13046-022-02578-w. Zhao R, Chen P, Qu C, Liang J, Cheng Y, Sun Z, Tian H. Cell Death Discov. In addition, the mice were weighed . Clin. Open Access First is to find an appropriate mathematical model for tumor volume evaluation from caliper-measured data. 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. 37, 331337 (2011). Isofluorane (0.95 x 2.0%) was applied for inhalational anesthesia, and intubation was performed. Hedrich, H.J. (8) This means that continuous, low dose antiangiogenic factor (VEGF) administration is needed. In addition, the gap between tumor volume values for caliper-based control and treatment groups is smaller than that for scanner measurements; the significant p-value was over 50 times higher when using calipers (p > 0.05) than with scanners (p < 0.001), suggesting that the caliper-based measurements are not statistically significant. Yes This helps to calculate accurate tumor volume from caliper measured data which will be useful for further animal experiments and as a consequence no small MRI measurements will be needed. ), 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. Evaluated the accuracy of common four formulas given in the literature to estimate xenograft tumor volumes based on manual caliper measurements and proposed formula (0,45 L*W*H) could estimate tumor volumes as good as prolate ellipsoid formula. 60, 21012103 (2000). Role of real-time sonography in assessment of breast diseases: a review of 200 cases (Abstr). 19, 6170 (1989). 2009, 18 (2009). The usual administration is via intravenous infusion; once every 2 or 3 weeks. The results of the three investigated cases using C38 mouse colon adenocarcinoma (Phase I, Phase III/3 control group, and Phase III/3 case group) were compared using tumor volume values from MRI measurements (Phase III/3 control and case groups, 23rd day) and evaluated data (Phase I MRI tumor volume calculated from linear curve fit, 24th day). b) Fluorescence picture was created using CD31 antibody immunohistochemistry staining to calculate vascularization area. Imaging 33, 2737 (2006). the tumor volume are made using digital calipers, and bio logical activity is quantified via the assessment of changes in tumor volume between treated and control mice. Yes In the case1 group, one mouse died on the 17th day. Ultrasonography as the Gold Standard for In Vivo Volumetric Determination of Chemically-induced Mammary Tumors. HHS Vulnerability Disclosure, Help The scanner-based measurements yield a higher correlation in this sense than caliper-based measurements. et al. 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. PMID: 11208850. Cancer Res. Contributed reagents/materials/analysis tools: ZS PK LK. Each day before the administration, the mice' body weight and tumor volume were measured and recorded. Frozen samples were used to create 15 m frozen cuts. Average of tumor volumes for every measurement days of the experiment can be seen in Fig 8. The manipulation of the handheld tool is at least as easy as holding a measurement caliper. The figure shows the results of a mouse (C4) from control group (first row), and a mouse (E9) from case group (second row). A direct 3D volume capture instrument, such as the TM900, will make a stereographic image of the tumor and reconstruct the tumor topography and shape. 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. Research and Innovation Center of Obuda University, Physiological Controls Group, Obuda University, Budapest, Hungary, Affiliation J. Clin. One can see that the two-dimensional mathematical model fits to the MRI-measured values, while the protocol-based values present totally different curve. In order to estimate tumor volume by external caliper, the greatest longitudinal diameter (length) and the greatest transverse diameter (width) were determined while mice were scruffed and conscious. Both methods cannot avoid variability introduced by the manipulation of the animal. 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. On the bottom left graph in Fig. Cancer Res. Mice in Phase I and Phase IV control group received no bevacizumab. B){00)Y$Ixlr{dYe}#@ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ ,^X_zN5:EZN]zM^k /Wu^ZZi#Ju.!L!z@u*kUim|+aZmjth-}z5'^|= 4L1_]qVZV*h@! The cause of death was tumor toxicity; however, none of the clinical criteria for euthanasia could be observed at these animals. Google Scholar. Figure 13. Thus, caliper-based measurements are less accurate the more the height of the stack deviates from its width. Breathing was monitored with piezoelectric transducer; temperature of the body was measured by rectal thermometer. Before To reduce the time of analysis one could e.g. Additionally, this technique is plagued by the inconsistent selection of tumor axes at subsequent examinations. Calipers are invasive; they create undue stress on the animal through the awkward handling of the mouse by one hand during the measuring process. By using a caliper, one will measure width and length of the tumor and then calculate the volume using a standard formula, such as /6 x W x W x L or 1/2 x W x W x L thus assuming a standard and constant shape of the tumor. When using calipers there is dependency in the measured data of the positioning by the operator of the tool on the xenograft. Even though all the three diameters can be measured, the estimation of the volume has quite a large error. The whole experiment consisted of four phases; the article focuses on the Phase III/3 and its results together with the comparison of Phase I and Phase III/3 (Fig 1). This results in the loss of information about its real growth.. With constant width and length, the measured volume does not change with the tumor shape. Google Scholar. This device measures the volume displacement of the water due to any object dipped into a measuring cylinder. This is a preview of subscription content, access via your institution. In several recent studies ([21, 22]), tumor volume is calculated assuming ellipsoid shape: In this study, the authors measured dimensions of rat mammary tumors using a caliper and using real-time compound B-mode ultrasonography. a) Haematoxylin Eosin (H&E) staining was applied to investigate tumor morphology. The mathematical relationship between MRI-measured tumor volume and mass was investigated to estimate accurate tumor volume using caliper-measured data. Competing interests: The authors have the following interests: Coauthors PK and DG are employed by Gedeon Richter Ltd. Avastin (bevacizumab) is manufactured by Genentech, Inc., South San Francisco, California, USA; EU patent expiry in 2019 in the US and 2022 in EU. Clipboard, Search History, and several other advanced features are temporarily unavailable. Results from an experiment that measures tumor volume and varies drug dose and measuring methods. Diagnostic accuracy of mammography, clinical examination, US, and MR imaging in preoperative assessment of breast cancer. Examination of tumor growth belongs not only to the basic medical research, but to the biomedical engineering field as well. Compute the volume assuming perfect ellipsoids. Can the Kuznetsov Model Replicate and Predict Cancer Growth in Humans? Because tumor volume measurements used by researchers and industries are sensitive and often rely on the accuracy, the cutting-edge TumorImagerTM line of scanners is the ideal, most reliable choice for taking such sensitive measurements. Controller-based therapy has the obvious advantage against e.g. Based on the experimental data, model identification can be carried out which describes the mathematical model of the investigated biological process. Pathol. The first group did not receive therapy, the second group received one 200 g bevacizumab dose for a treatment period (protocol-based therapy), and the third group received 1.1 g bevacizumab every day (quasi-continuous therapy). 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. Bevacizumab administration was started on the 7th day in both cases. endobj The C38 colorectal carcinoma line was maintained by serial subcutaneous transplantations in C57Bl/6 mice. Figure 6. 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. Using the above mentioned iterative method, the resulted equation is by water displace ment (c.c) Vol. Determining tumor volume is a useful and quantitative way to monitor tumor progression. In addition, even though there is about a 20% difference between the low-dose treatment group for the scanner measurements, the caliper-based measurements do not show any effect for this dose. Of course, for the closed-loop design frequent and precise tumor volume measuremets are required, thus the problem of tumor volume measurement has to be solved as well. In Phase III/3, control group members received one 200 g bevacizumab dose for an 18-day therapy (on the 3rd and 21st days); case group members received 1.11 g bevacizumab every day for 20 days. Tumor measurement by TumorImager-2TM. These together with the tumor shape and all obtained data can easily be traced and consulted afterwards. A study[4] (Figure 5.) Fj^P;7? Notice that in the caliper group, the average standard deviation is larger than that of the group whose tumors were measured by Biopticons TumorImager scanner. 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]. (Budapest, Hungary). Usually, 3.0 x 10 6 cells are needed per injection. In order to assess interobserver variation, each . Figure 16. depicts the results from a study attended by Biopticon in which ten subcutaneous tumors in mice were measured by scanner and caliper by four operators. For the most precise result, tumor mass values, which were measured at the end of the experiment, were compared in the statistical analysis. Accurately measure the tumor (in cm) using a caliper. PubMed Central Powered by WordPress The 1st Department of Pathology and Experimental Cancer Research of the Semmelweis University (Budapest, Hungary) and the Physiological Controls Group of the Obuda University (Budapest, Hungary) began collaborating on antiangiogenic therapy research in 2012including the current experimental investigations. Tumor volume measurement was performed by digital caliper and small animal MRI. This can happen if the mouse is pressed into the mask or if the body is stretched when held. 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 Bevacizumab (Avastin) [1] is an exogenous inhibitor, which inhibits the biological activity of human VEGF [2]. Lifetime dose-response relationships for mammary tumor induction by a single administration of N-methyl-N-nitrosourea. The other eight tumors exhibit forms that cannot be compared to a perfect ellipsoid. In the top-left graph (Figure 19. The TumorImagerTM line of scanners by Biopticon Corporation fixes these problems by keeping the animals relaxed during measuring and yielding measurements closer to actual values than caliper-based measurements. Figure 3. The tumor can be more and sometimes less visible or popped up from under the skin. Objectives: Volume measurement of subcutaneous xenograft tumors in nude mice models is an important metric to assess tumor growth or response to therapy. Hence, the first step has to be the vasculature normalization with the reconstruction of the balance of pro- and antiangiogenic factors. Generally, to make caliper measurements, the measurer first traps the tail of the mouse under her fingers, then, grabs the neck of the mouse, and aligns the mouse in her hand in a way to expose the tumor for length and width measurements. During the scan, a mouse should be held in a relaxed manner without stretching its skin to cause unwanted deformation of the tumor body. The authors declare no competing financial interests. Modulation of mammary tumor vascularization by mast cells: Ultrasonographic and histopathological approaches. 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 size was measured every 3 days using a digital caliper and computed according to the ellipsoidal calculation formula: V . 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