State of art of SBRT for primary lung cancer and secondary lung metastases

Abstract (English)

Potential role of Stereotactic Body Radiotherapy (SBRT) or Stereotactic Ablative radiotherapy (SABR) is very high rate of tumor control, no or little toxicity, it’s non-invasive procedure, and convenient for ambulatory use with very few sessions. Furthermore, the benefit of this technique is that several lesions can be treated at the same time and retreatments are possible. Respiratory movement control is very important issue with the goal to reduce margin and obtain precise targeting. Stereotactic body radiotherapy can be delivered by different devices: Helical tomotherapy, linear accelerator treatment with 4DCT or cyberknife. All of the mentioned use one of the proposed techniques to solve the problem of respiratory motion: Create a ITV as a summary of CTV’s created on all phases of the 4D CT (valid method for all machines), create ITV mid-ventilation as a summary of CTV’s based on a statistical calculation, gating, tracking or making the patient static (breath-hold technique or High frequency percussive ventilation). There are few side effects of SBRT and unlike surgery, 90-day mortality is extremely rare. Late effects depend on anatomical localization and total dose. In centrally located tumors, it is recommended to administer 54-60Gy in > 3 fractions. In general, indications for SBRT are mainly less than 3 lesions with extra-thoracic disease under control. Compared to surgery, studies have shown that there is no difference in local control, non-inferior in terms of toxicity, SBRT is more cost-effective, less invasive and can be applied in various anatomical sites. Moreover, SBRT/SRS enhance antitumor immunity and provoke antitumor effect outside of the irradiated volume. In conclusion, SBRT presents safe and efficient treatment option for medically inoperable patients or patients refusing surgery, for isolated parenchymal relapse patient, in oligometastatic patients.