| Abstract | Gliomi su jedni od najčešćih tumora mozga, a gliomima niskog stupnja malignosti (LGG) pripadaju oni gradusa II. Unatoč tome što su manje agresivni od tumora mozga viših gradusa, zbog difuzne infiltrativnosti i moguće maligne transformacije ovaj tip tumora potrebno je na vrijeme dijagnosticirati i odgovarajuće liječiti. Jedan od najvažnijih simptoma glioma je epileptički napadaj. Više od 80 % bolesnika ima epileptičke napadaje i često su oni prvi simptom glioma. Progresijom tumora povećava se i učestalost napadaja. Osim anamneze i fizikalnog pregleda, u dijagnostici LGG-a koriste se i radiološke, histološke i molekularnopatološke metode. Od radioloških metoda najvažnije su magnetska rezonanca (MR) i kompjuterizirana tomografija (CT), dok u napredne dodatne metode spadaju perfuzijska magnetska rezonanca (pMR), funkcijska magnetska rezonanca (fMR), MR spektroskopija i pozitronska emisijska tomografija (PET). Histološki se difuzni gliomi mogu podijeliti u astrocitome, oligodendrogliome i mješovite tumore, a potonji mogu biti gradusa II, III ili IV. U LGG pripadaju gliomi gradusa II, a karakterizira ih niska mitotska aktivnost, dobra diferenciranost glijalnih stanica i atipične jezgre. Molekularna dijagnostika klasificira difuzne gliome prvenstveno na temelju postojanja mutacije izocitrat dehidrogenaze (IDH), stoga se oni klasificiraju u tri skupine: astrocitom, IDH mutant u kojem nije prisutna 1p/19q kodelecija, oligodendrogliom, IDH mutant s 1p/19q kodelecijom te glioblastom u kojem je IDH intaktna (divljeg tipa). Međutim, postoje mutacije nekih gena specifične za pojedini tip tumora. Za potvrdu postojanja IDH mutacije koriste se imunohistokemijske metode, a za dokaz prisutnosti 1p/19q kodelecije fluorescentna in situ hibridizacija (FISH). Liječenje LGG-a je složeno i zahtjeva interdisciplinarni pristup. Prvu liniju liječenja predstavlja kirurška resekcija tumora koja mora biti što opsežnija, a opseg resekcije korelira sa sveukupnim preživljenjem. Onkološko liječenje koje uključuje kemoterapiju i zračenje namijenjeno je za visokorizične pacijente. Kemoterapija koja se najčešće koristi su derivati nitrozoureje i temozolomid. Što se tiče radioterapije, optimalna doza koja se koristi je između 45 i 54 Gy- a. Međutim, ponekad su gliomi otporni na navedene modalitete liječenja te se radi na ciljanoj terapiji utemeljenoj na molekularnim markerima i cjepivima. Potonji predstavljaju budućnost liječenja LGG-a. |
| Abstract (english) | Gliomas are one of the most common brain tumors. Low-grade gliomas belong to those of grade 2. Despite being less aggressive than higher-grade brain tumors, due to diffuse infiltration and possible malignant transformation, this type of tumor needs to be diagnosed and treated on time. An epileptic seizure is one of the most important symptoms of glioma. More than 80 % of patients have epileptic seizures and they are often the first symptom of glioma. The frequency of seizures is increased by tumor progression. In addition to medical history and physical examination, radiological, histological, and molecular methods are used in the diagnosis of LGG. The most important radiological methods are magnetic resonance imaging (MRI) and computed tomography (CT), while advanced additional methods include perfusion magnetic resonance imaging (PWI), functional magnetic resonance imaging (fMRI), MRI spectroscopy, and positron emission tomography (PET). Diffuse glioma can be histologically divided into astrocytoma, oligodendroglioma, and mixed tumors, which then belong to grades 2, 3, or 4. LGGs include grade 2 gliomas and are characterized by low mitotic activity, well-differentiated glial cells, and atypical nuclei. Molecular classification of diffuse gliomas is primarily based on the existence of isocitrate dehydrogenase (IDH) mutation; therefore, they are classified into three groups: astrocytoma, IDH mutant without 1p/19q codeletion, oligodendroglioma, IDH mutant with 1p/19q codeletion and glioblastoma, IDH wild type. However, there are mutations in several genes specific to a particular type of tumor. Immunohistochemical methods are used to confirm IDH mutation, while fluorescence in situ hybridization (FISH) is used to confirm 1p/19q codeletion. LGG’s treatment is complicated and requires an interdisciplinary approach. Surgical resection is the first-line treatment and must be extensive; the extent of resection correlates with overall survival. Oncology treatment based on chemotherapy and radiotherapy is intended for high-risk patients. Nitrosourea derivates and temozolomide are the most used chemotherapy. As for radiotherapy, the optimal dose is between 45 and 54 Gy. However, sometimes gliomas are resistant to these treatment modalities, and target therapy based on molecular markers and vaccines is being developed. The latter is the future of LGG’s treatment. |
