Clinical Results of Stereotactic Body Frame based Fractionated Radiosurgery for Primary or Metastatic Thoracic Tumors

PURPOSE: The aim of the study was to evaluate the treatment outcomes of stereotactic radiosurgery (SRS) using a stereotactic body frame for primary or metastatic thoracic tumors. Methods and Materials: Between January 1998 and December 2003, 101 lesions from 91 patients with primary or metastatic thoracic tumors were treated. The eligible patients included 38 with primary lung cancers and 53 with metastatic tumors from the lung, liver, gastrointestinal and other organs. All patients were immobilized using a stereotactic body frame and permitted to breathe shallowly. The respiratory movement was restricted by a diaphragm controller when the tumor movement was greater than 5 mm. Recently, for further restriction of tumor movement, an active breathing control (ABC) apparatus was used in some trained patients whose tumors located in lower lobe. Three to eight coplanar or non-coplanar photon beams were used to adequately cover the planning target volume. A dose of 10~12 Gy per fraction was given three to four times over consecutive days, to a total dose of 30~48 Gy (median 40 Gy). Local control was assessed as complete or partial responses and by a stable disease, as measured by serial chest CT scans at 1 month, and then every 3-months, and/or 18FDG-PET scans 1 month after treatment. The median follow-up period was 14 months, ranging from 4 to 56 months. RESULTS: The overall response rate was 82%, with twenty (22%) complete and 55 (60%) partial responses. The rate of crude local control in all patients was 86% and the one- and two-year local progression free survival rates were 90 and 81%, respectively. The patients who received 48 Gy showed better local progression free survival than those that received 40 Gy or less (one-year; 100% vs. 86.7%), but this was not statistically significant. Of the 21 patients with primary lung cancer, local progression was observed in 3, at 12, 21 and 26 months after treatment, and the one- and two- year local progression free survival rates were 93 and 81%, respectively. The set-up error, as checked by CT-simulation and portal films, for every treatment was within 5 mm in all directions (X, Y and Z axis). No pulmonary complications greater than RTOG toxicity criteria grade 2 were observed. CONCLUSION: From our experience of the stereotactic body frame based radiosurgery it appears a safe and promising treatment modality for the local management of primary or metastatic lung tumors. The optimal total dose, fractionation schedule and treatment volume should be modified after a longer follow-up of these results. Further study related to the optimal evaluation tools is also necessary to differentiate local tumor progression from radiation-induced pulmonary injury

Preliminary Results of Stereotactic Body Frame Based Fractionated Radiosurgery on Consecutive Days for Primary Lung Cancer or Metastatic Lung Tumors

To evaluate the feasibility and treatment outcomes of stereotactic radiosurgery (SRS) using a stereotactic body frame (Precision TherapyTM), we prospectively reviewed 34 tumors of the 28 patients with primary or metastatic intrathoracic lung tumors. Eligible patients included were 9 with primary lung cancer and 19 with metastatic tumors from the lung, liver and many other organs. A single dose of 10 Gy to the clinical target volume (CTV) was delivered to a total dose of 30~40 Gy with 3~4 fractions. Four to 8 coplanar or non-coplanar static fields were generated to adequately cover the planning target volume (PTV) as well as to exclude the critical structures as much as possible. More than 90% of the PTV was delivered the prescribed dose in the majority of cases (average; 96%, range; 74%~100%). The mean PTV was 41.4 cc ranging from 4.4 to 230 cc. Set-up error was within 5 mm in all directions (X, Y, Z axis). The response was evaluated by using a chest CT and or 18FDG-PET scans after SRS treatment, 11 patients (39%) showed complete response, 12 (43%) partial response (decrease of more than 50% of the tumor volume), and 4 patients showed minimally decreased tumor volume or stable disease, but 1 patient showed progressive disease. With a median follow-up period of 18 months, a median local disease progression free interval was 18 months ranging from 7 to 35 months. Although all patients developed grade 1 radiation pneumonitis within 3 months, none had symptomatic or serious late complications after completing SRS treatment. Given these observations, it is concluded that the stereotactic body frame based SRS is a safe and effective treatment modality for the local management of primary or metastatic lung tumors. However, the optimum total dose and fractionation schedule used should be determined after the longer follow-up of these results.

Preliminary Results of Stereotactic Radiosurgery Using Stereotactic Body Frame / 대한방사선종양학회지

PURPOSE: To evaluate efficacy and complication of stereotactic radiosurgery using stereotactic body frame. METHODS AND MATERIALS: From December 1997 to June 1999, 11 patients with primary and metastatic tumors were treated with stereotactic radiosurgery using stereotactic body frame(Precision Therapy(TM)). Three patients were treated with primary hepatoma and seven with metastatic tumor from liver, lung, breast, trachea and one with arteriovenous malformation on neck. We used vacuum pillow for immobilization and made skin marker on sternum and tibia area with chest marker and leg marker. Diaphragm control was used for reducing movement by respiration. CT-simulation and treatment planning were performed. Set-up error was checked by CT-Simulator before each treatment. Dose were calculated on the 80~90% isodose of isocenter dose and given consecutive 3 fractions for total dose of 30 Gy (10 Gy/fraction). RESULTS: Median follow-up was 12 months. One patient (9%) showed complete response and four patients (36%) showed partial response and others showed stable disease. Planning target volumes (PTV) ranged from 3 to 111 cc (mean 18.4 cc). Set-up error was within 5 mm in all directions (X, Y, Z axis). There was no complication in all patients. CONCLUSION: In primary and metastatic tumors, stereotactic radiosurgery using stereotactic body frame is very safe, accurate and effective treatment modality.