Ependimom ve Pons Gliomları
Özet
Bu çalışma, santral sinir sistemi tümörlerinden ependimomlar ve pons gliomlarını güncel DSÖ (WHO CNS5) kriterleri çerçevesinde klinik, histopatolojik ve moleküler özellikleri ile ele almaktadır. Ependimomlar; supratentoryal, posterior fossa ve spinal kompartmanlarda yerleşen, histolojik dereceleri ile moleküler füzyonlarına (ZFTA/YAP1 füzyonları, PFA/PFB grupları) göre sınıflandırılan glial tümörlerdir. İlk tedavileri maksimum güvenli rezeksiyon olup, gerekli durumlarda fokal radyoterapi ve kemoterapi kombinasyonları uygulanmaktadır. Pons gliomları ise fokal ve diffüz olarak ikiye ayrılmaktadır. Çocukluk çağında sık görülen Diffüz İntrinsik Pontin Gliomlar (DIPG), patognomonik H3 K27M mutasyonları ve agresif seyirleriyle öne çıkmakta, talamus, pons veya omurgada yerleşebilmektedir. DIPG klinik seyrini değiştirebilen tek standart tedavi yöntemi radyoterapi olmakla birlikte, günümüzde epigenetik modifiye edici ajanlar (panobinostat), temozolomid uygulamaları ve GD2 hedefli CAR-T hücre tedavileri gibi yenilikçi ve umut verici terapötik yaklaşımlar üzerinde yoğun araştırmalar yürütülmektedir. Tümörlerin yönetiminde cerrahi yaklaşımın riskleri nedeniyle, deneyimli multidisipliner ekiplerce tedavi öncesi biyopsi ve moleküler profilleme yapılması prognostik açıdan kritik önem taşımaktadır.
This study evaluates ependymomas and pons gliomas, two significant central nervous system tumors, based on the current WHO CNS5 classification system, incorporating clinical, histopathological, and molecular parameters. Ependymomas are circumscribed glial tumors located in supratentorial, posterior fossa, or spinal compartments, classified by both anatomical site and molecular alterations such as ZFTA/YAP1 fusions and PFA/PFB sub-groups. The primary therapeutic intervention is maximal safe surgical resection, which may be supplemented by focal radiotherapy and salvage chemotherapy regimens. Brainstem gliomas are distinguished as focal or diffuse subtypes. Diffuse Intrinsic Pontine Gliomas (DIPG), highly prevalent in pediatric cohorts, are characterized by aggressive clinical behavior and pathognomonic H3 K27M mutations, typically manifesting in the pons, thalamus, or spinal cord. Although conventional radiotherapy remains the only modality established to alter the survival trajectory of DIPG, contemporary research actively explores epigenetic modifying agents like panobinostat, adjuvant temozolomide protocols, and novel GD2-targeted CAR-T cell immunotherapies. Given the profound neurosurgical risks associated with brainstem lesions, pre-treatment biopsy combined with precise molecular profiling is critical to optimizing diagnostic accuracy and guiding targeted therapeutic strategies.
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