Beschreibung:
<jats:title>Abstract</jats:title>
<jats:p>Background: Volume is the most sensitive and accurate parameter to assess tumor response to treatment. We have proposed that data be expressed as volume in cubic centimetres TVA (Tumor Volume Analysis)1. When we applied TVA to a breast cancer trial and converted the data from diameter centimetres to volume in cubic centimetres the differences were statistically signifcant2.Three dimensional measurements: Volume measurements are most accurate if all three dimensions are measured to record any asymmetric growth[ref]. In Table 1 diameter permutations are shown of a 3cm mass together with percentage changes in each example. This demonstrates the extent that changes in the lesser two axes of a mass affect tumor volume. Accurate 3D volume measurement is essential to estimate tumor doubling.Tumor Doubling and Redoubling: Tumor doubling for a carcinoma is quoted as under 177 days [ref] or under 500 days[ref]. With a mean of 100 days[ref] or 117 days[ref]. Much of the work has been carried out on metastatic pulmonary nodules of various tumors. An early paper did quote doubling times as by diameter and provided a graph to convert data into volume8. A calculator has been described and patented to provide these functions2.Tumor Doubling Time (TDT): Tumor doubling can be regarded as an increase in volume over a unit of time[8, ref]. We propose this TDT be quantified with the period of growth expressed in days for example TDT 120 implies a tumor doubling time of 120 days. A formula that does allow for exponential growth assuming a constant growth is as follows: TDT = D x log(2)/log(1+ r/100). Where TDT = tumor doubling time; D = interval in DAYS between volume measurements; r = rate of growth; r/100 = (Vol 2-Vol 1)/Vol 1 x 100%. This option for measuring tumor doubling can be added as a fourth and further facility to the calculator already described [Patent PCT/GB07/003526]2Conclusions: 1. Tumor doubling is qualified by volume changes in cm3. Tumor doubling time (TDT) in days quantifies tumor doubling. 2. Measurement of TDT can be made as an extra facility on the calculator already described. The calculator can be used to estimate TDT using two measured volumes and the interval in days. 3. A similar formula can also be used to measure downsizing in response to neoadjuvant therapy as complete response time (CRT).References:1. SABCS 2007 Poster # 2021Tumor Volume Analysis. A better way than RECIST? [A B Gordon, J Stebbing, R C Coombes]2. SABCS 2008 Poster # 4023 Tumor Volume Analysis in Clinical Oncology. [A B Gordon, J Stebbing, R C Coombes] 8. V P Collins et al. Observations on Growth Rates of Human Tumours. American Journal of Roentgenology. V. 76 p. 988-1000 1956Table 1. Volume Calculation of Three Dimensional MassSHAPE SphereOne Diameter3x3x3cm14.14cm3100%TangerineTwo Diameters3x3x2cm9.42cm367%EggTwo Diameters3x2x2cm6.28cm344%CigarTwo Diameters3x1x1cm1.57cm311%DateThree Diameters3x2x1cm3.14cm322% </jats:p>
<jats:p>Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 5030.</jats:p>