Leith Hathout1, Whitney B Pope2, Albert Lai3,4, Phioanh L Nghiemphu3,4, Timothy F Cloughesy3,4, Benjamin M Ellingson2,3,5,6. 1. Harvard Medical School, 25 Shattuck Street, Boston, MA 02115, USA. 2. Department of Radiological Sciences, David Geffen School of Medicine, University of California, Los Angeles, 924 Westwood Boulevard, Suite 615, Los Angeles, CA 90024, USA. 3. UCLA Neuro-Oncology Program, David Geffen School of Medicine, University of California, Los Angeles, CA 90095, USA. 4. Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, CA 90095, USA. 5. Department of Biomedical Physics, David Geffen School of Medicine, University of California, Los Angeles, CA 90095, USA. 6. Department of Bioengineering, Henry Samueli School of Engineering & Applied Science, University of California Los Angeles, Los Angeles, CA 90095, USA.
Abstract
BACKGROUND: Contrast-enhancing low-grade diffuse astrocytomas are an understudied, aggressive subtype at increased risk because of few radiographic indications of malignant transformation. In the current study, we tested whether tumor growth kinetics could identify tumors that undergo malignant transformation to higher grades. METHODS: Thirty patients with untreated diffuse astrocytomas (WHO II) that underwent tumor progression were enrolled. Contrast-enhancing and T2 hyperintense tumor regions were segmented and the radius of tumor at two time points leading to progression was estimated. Radial expansion rates were used to estimate proliferation and invasion rates using a biomathematical model. RESULTS: Radial expansion rates for both contrast-enhancing (p = 0.0040) and T2 hyperintense regions (p = 0.0016) were significantly higher in WHO II-IV tumors compared with nontransformers. Similarly, model estimates showed a significantly higher proliferation (p = 0.0324) and invasion rate (p = 0.0050) in WHO II-IV tumors compared with nontransformers. CONCLUSION: Tumor growth kinetics can identify contrast-enhancing diffuse astrocytomas undergoing malignant transformation.
BACKGROUND: Contrast-enhancing low-grade diffuse astrocytomas are an understudied, aggressive subtype at increased risk because of few radiographic indications of malignant transformation. In the current study, we tested whether tumor growth kinetics could identify tumors that undergo malignant transformation to higher grades. METHODS: Thirty patients with untreated diffuse astrocytomas (WHO II) that underwent tumor progression were enrolled. Contrast-enhancing and T2 hyperintense tumor regions were segmented and the radius of tumor at two time points leading to progression was estimated. Radial expansion rates were used to estimate proliferation and invasion rates using a biomathematical model. RESULTS: Radial expansion rates for both contrast-enhancing (p = 0.0040) and T2 hyperintense regions (p = 0.0016) were significantly higher in WHO II-IV tumors compared with nontransformers. Similarly, model estimates showed a significantly higher proliferation (p = 0.0324) and invasion rate (p = 0.0050) in WHO II-IV tumors compared with nontransformers. CONCLUSION:Tumor growth kinetics can identify contrast-enhancing diffuse astrocytomas undergoing malignant transformation.
Authors: Magdalena U Bogdańska; Marek Bodnar; Monika J Piotrowska; Michael Murek; Philippe Schucht; Jürgen Beck; Alicia Martínez-González; Víctor M Pérez-García Journal: PLoS One Date: 2017-08-01 Impact factor: 3.240