AUTOFLUORESCENCE AND 5-AMINOLEVULINIC ACID INDUCED FLUORESCENCE OF NORMAL BRAIN AND GLIOMA IN WISTAR RATS A.Čiburys, D.Gadonas, R.Gadonas, D.Kaškelytė, A.Piskarskas, V.Smilgevičius Laser Research Center, Vilnius University J.Didžiapetrienė, G.Graželienė, A.Sukackaitė Lithuanian Oncology Center I.Gudinavičienė Department of Pathology, Kaunas Medical University Hospital K.Skauminas Institute for Biomedical Research, Kaunas Medical University

Motivation Cerebral gliomas are among the most frequent tumours of CNS having the worst prognosis Extent of removal of cerebral gliomas is a prognostically important factor Because of the infiltrating nature of gliomas the most frequent cause for morbidity and mortality is the further growth of the tumour from infiltrated brain areas which look macroscopically healthy Methods for visualization of tumours existing at present are expensive, not precise enough and technically hard to apply intraoperatively The application of method based on fluorescence allowing the detection of tumor borders and visualization intraoperatively would help to more precise and selective removal of cerebral gliomas and it would result in more radical surgery

Clinical Material and Methods In this period 408 adult patients with newly diagnosed supratentorial, lobar located, hystologically confirmed cerebral gliomas underwent surgical treatment. The retrospective period for the study is from January, 1994 to December, males192 females Patients median age was 56 years (range years).

Newly Diagnosed Cases in the Period from January 1994 to December 2000 A - Astrocytoma (grade II) AA - Anaplastic Astrocytoma GBM - Glioblastoma Multiforme ODG - Oligodendroglioma

Survival rates for patients with cerebral gliomas Histological 1 year 2 years 3 years type A %52.6%46.1% AA %13.0% 2.6% GBM %7.5% 3.3% ODG %34.9%23.3% Total Survival rates

Motivation Cerebral gliomas are among the most frequent tumors of CNS having the worst prognosis Extent of removal of cerebral gliomas is a prognostically important factor Because of the infiltrating nature of gliomas the most frequent cause for morbidity and mortality is the further growth of the tumor from infiltrated brain areas which look macroscopically healthy Methods for visualization of tumors existing at present are expensive, not precise enough and technically hard to apply intraoperatively The application of method based on fluorescence allowing the detection of tumor borders and visualization intraoperatively would help to more precise and selective removal of cerebral gliomas and it would result in more radical surgery

Motivation Cerebral gliomas are among the most frequent tumors of CNS having the worst prognosis Extent of removal of cerebral gliomas is a prognosticaly important factor Because of the infiltrating nature of gliomas the most frequent cause for morbidity and mortality is the further growth of the tumor from infiltrated brain areas which look macroscopically healthy Methods for visualization of tumors existing at present are expensive, not precise enough and technically hard to apply intraoperatively The application of method based on fluorescence allowing the detection of tumor borders and visualization intraoperatively would help to more precise and selective removal of cerebral gliomas and it would result in more radical surgery

Motivation Cerebral gliomas are among the most frequent tumors of CNS having the worst prognosis Extent of removal of cerebral gliomas is a prognosticaly important factor Because of the infiltrating nature of gliomas the most frequent cause for morbidity and mortality is the further growth of the tumor from infiltrated brain areas which look macroscopically healthy Methods for visualization of tumors existing at present are expensive, not precise enough and technically hard to apply intraoperatively The application of method based on fluorescence allowing the detection of tumor borders and visualization intraoperatively would help to more precise and selective removal of cerebral gliomas and it would result in more radical surgery

Motivation Cerebral gliomas are among the most frequent tumors of CNS having the worst prognosis Extent of removal of cerebral gliomas is a prognosticaly important factor Because of the infiltrating nature of gliomas the most frequent cause for morbidity and mortality is the further growth of the tumor from infiltrated brain areas which look macroscopically healthy Methods for visualization of tumors existing at present are expensive, not precise enough and technically hard to apply intraoperatively The application of method based on fluorescence allowing the detection of tumor borders and visualization intraoperatively would help to more precise and selective removal of cerebral gliomas and it would result in more radical surgery

Objectives To investigate in vivo fluorescence of rat brain tumours sensitised by 5 – ALA - induced porphyrins To evaluate the potentials of intraoperative diagnostics of cerebral gliomas based on PpIX fluorescence

Materials and Methods Tumour model: rat brain glioma inserted to Wistar rats into left pariental area Experiment is carried out after 2 weeks incubation period with intraperitoneal unsensitivity 6 hours prior to the experiment 300 mg/kg of 5-aminolevulinic acid is injected intravenously

Haem Ferrochelatase Fe 2+ Protoporphyrin IX Porphyrin Intermediates 5-ALA 5-ALA synthesis Glycine + Succinyl CoA Exogenous 5-ALA Feedback Control mechanism

Techniques Experimental set-up

Techniques Light source: high pressure Xe lamp Quartz fiber probe: 7 fibers for excitation and 1 for collection, light spot diameter 3mm The distance from probe end to tissue sample was kept constant (0.8-1 mm) At each site three measurements were taken and averaged

Excitation and filtering

Autofluorescence

Normal brain tissue Brain tumour

Pharmacokinetics

Results brain tissue from healthy cerebral hemisphere tumour violated cerebral hemisphere

Conclusions We examined in vivo fluorescence spectra of normal brain and brain glioma in experimental rats injected with 5-aminolevulinic acid Detected spectral signature of PpIX in glioma with contrast ratio up to 10 can be the base for intraoperative fluorescence diagnostics