Program / Abstract Book - KMU WWW3 Server for Education ...

No. 72 (PP 5)
The morphological change after molecular targeting therapy of malignant brain
tumor
Tatsuo Sawada 1 , Yoshinori Takekawa 2 , Saori Okamoto 3 , Takashi Maruyama 3 , and Noriyuki
Shibata 1
1 Department of Pathology, Tokyo Women’s Medical University
2 Department of Neurosurgery Tokyo Women’s Medical University
3 Department of Surgical Pathology Yokosuka Municipal Hospital, Japan
(Background) The molecular targeting agents that are currently available for various malignant
neoplasms. The effects of molecular targeting agents are divided into two subgroups, oncogene
addiction (OA) and non-oncogene addiction (NOA). Bevacizumab, anti-vascular endothelial growth
factor antibody is one of major agents of non-oncogenic addition although the therapy is permitted only
experimentally in Japan. Malignant glioma, especially, glioblastoma (GB), and highly vascularized brain
tumors are thought to be the one of the attractive targets for anti-angiogenic therapies. To elucidate
morphological changes of tumor after NOD therapy is important to evaluate the effects of the drug. So
we examined the morphological change of malignant glioma after Bavacizumab therapy using 3 autopsy
cases.
(Materials and Methods) Three cases in men were used. The range of age is from 37 to 64yrs. These 3
cases received Bemacizumab therapy, and radiation therapies were combined. The microscopic slides of
surgical resected and autopsied specimen were compared using HE and immunohistochemistry (IHC)
for vascular endothelial growth factor, EGF A and C, vascular endothelial growth factor receptor, Fltand
Flk-1, platelet derived growth factor (PDGF), CD31, CD34, smooth muscle cell actin (SMA) and
aquaporin 1 and 4. And 5 cases of GB are examined for control.
(Results) No significant change of morphology of tumor cells is identified after Bevacizumab therapy,
but the morphology of neovasculature is different from conventional GB. A few glomeruloid
appearances and hyperplasia of SMA positive cells are identified. On IHC, the reactivity for VEGF A
was decreased but VEGF-C and Flt-1 were preserved.
(Conclusion) The morphological difference between with and without administration of Bemasizumab
in neovasculature suggests decreased expression of VEGF-A.
- 125 -