Mikrodalga Termoterapinin Temel Prensipleri
Özet
Radyolojik görüntüleme yöntemlerindeki gelişmeler, 4 cm’den küçük rastlantısal küçük renal kitlelerin (KRK) tanı oranını artırmıştır. Bu tümörlerde altın standart tedavi parsiyel nefrektomi olsa da, yüksek komorbidite yükü olan veya cerrahi istemeyen hastalarda mikrodalga termoterapi (MDT) gibi fokal ablatif yöntemler öne çıkmaktadır. MDT, hedef dokuya yerleştirilen antenler aracılığıyla elektromanyetik dalgalar göndererek su moleküllerini hareket ettirir ve sürtünme enerjisiyle 80-100 °C arasında yüksek ısı oluşturur. Radyofrekans ablasyona (RFA) kıyasla ısı üretimi daha hızlı ve güçlü olup, dokunun iletkenliğine bağımlı olmadığından kemik ve akciğer gibi yalıtkan dokularda da etkilidir. Ayrıca, hastanın bacaklarına elektrot yerleştirilmesine gerek duyulmaz ve anten içi soğutma sitemi sayesinde cilt yanığı riski önlenerek daha geniş ablasyon alanı sağlanır. Yapılan klinik ve retrospektif çalışmalar, MDT’nin yüksek teknik başarıya sahip, böbrek fonksiyonlarını koruyan ve düşük nüks oranları sunan güvenli bir alternatif olduğunu doğrulamaktadır. Yöntem, son yıllarda düşük riskli lokalize prostat kanserinin fokal tedavisinde de sağlıklı dokuyu koruyup yan etkileri azaltmak amacıyla umut verici bir alternatif olarak test edilmeye başlanmıştır.
Advances in radiological imaging have increased the detection rate of incidental small renal masses (SRMs) smaller than 4 cm. Although partial nephrectomy is the gold standard for these tumors, focal ablative methods like microwave thermotherapy (MTT) emerge as strong options for elderly patients, those with high comorbidities, or those reluctant to undergo surgery. MTT delivers electromagnetic waves via antennas inserted directly into the target tissue, causing water molecules to oscillate and generate friction energy between 80-100 °C, leading to tissue death. Compared to radiofrequency ablation (RFA), MTT produces heat more rapidly and powerfully, and since it does not rely on electrical conductivity, it remains effective in insulating tissues like bone and lung. Furthermore, it eliminates the need for grounding pads on the patient's legs, and its internal cooling system prevents skin burns while enabling a larger ablation zone. Clinical and retrospective studies demonstrate that MTT is a safe alternative with high technical success, preserved renal function, and low recurrence rates. Recently, this method has also been tested as a promising alternative in the focal treatment of low-risk localized prostate cancer to minimize side effects by preserving healthy tissue.
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