Limits...
Clinical outcome of fiducial-less CyberKnife radiosurgery for stage I non-small cell lung cancer.

Jung IH, Song SY, Jung J, Cho B, Kwak J, Je HU, Choi W, Jung NH, Kim SS, Choi EK - Radiat Oncol J (2015)

Bottom Line: Eight patients died due to cancer progression.The results showed that fiducial-less CKRS shows comparable local tumor control and survival rates to those of LINAC-based SABR or CKRS with a fiducial marker.Thus, fiducial-less CKRS using Xsight lung tracking system can be effectively and safely performed for patients with medically inoperable stage I non-small cell lung cancer without any risk of procedure-related complication.

View Article: PubMed Central - PubMed

Affiliation: Department of Radiation Oncology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.

ABSTRACT

Purpose: To evaluate the treatment results in early stage non-small cell lung cancer patients who have undergone fiducial-less CyberKnife radiosurgery (CKRS).

Materials and methods: From June 2011 to November 2013, 58 patients underwent CKRS at Asan Medical Center for stage I lung cancer. After excluding 14 patients, we retrospectively reviewed the records of the remaining 44 patients. All analyses were performed using SPSS ver. 21.

Results: The median age at diagnosis was 75 years. Most patients had inoperable primary lung cancer with a poor pulmonary function test with comorbidity or old age. The clinical stage was IA in 30 patients (68.2%), IB in 14 (31.8%). The mean tumor size was 2.6 cm (range, 1.2 to 4.8 cm), and the tumor was smaller than 2 cm in 12 patients (27.3%). The radiation dose given was 48-60 Gy in 3-4 fractions. In a median follow-up of 23.1 months, local recurrence occurred in three patients (2-year local recurrence-free survival rate, 90.4%) and distant metastasis occurred in 13 patients. All patients tolerated the radiosurgery well, only two patients developing grade 3 dyspnea. The most common complications were radiation-induced fibrosis and pneumonitis. Eight patients died due to cancer progression.

Conclusion: The results showed that fiducial-less CKRS shows comparable local tumor control and survival rates to those of LINAC-based SABR or CKRS with a fiducial marker. Thus, fiducial-less CKRS using Xsight lung tracking system can be effectively and safely performed for patients with medically inoperable stage I non-small cell lung cancer without any risk of procedure-related complication.

No MeSH data available.


Related in: MedlinePlus

DVH and example of case. (A) DVH. (B) CT image, before treatment. (C) CT image, 1 month after CKRS. After delivery of 60 Gy for 4 fractions, we checked chest CT. This figure showed partially responded tumor after CKRS. (D) CT image, 5 months after CKRS. After 5 months, asymptomatic radiation pneumonitis occurred. (E) CT image, 11 months after CKRS. After 11 months, radiation fibrosis was observed without any symptom. (F) CT image, 24 months after CKRS. Until last follow-up, tumor did not progress with radiation change. DVH, dose volume histogram; CT, computed tomography; CKRS, CyberKnife radiosurgery.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4493433&req=5

Figure 3: DVH and example of case. (A) DVH. (B) CT image, before treatment. (C) CT image, 1 month after CKRS. After delivery of 60 Gy for 4 fractions, we checked chest CT. This figure showed partially responded tumor after CKRS. (D) CT image, 5 months after CKRS. After 5 months, asymptomatic radiation pneumonitis occurred. (E) CT image, 11 months after CKRS. After 11 months, radiation fibrosis was observed without any symptom. (F) CT image, 24 months after CKRS. Until last follow-up, tumor did not progress with radiation change. DVH, dose volume histogram; CT, computed tomography; CKRS, CyberKnife radiosurgery.

Mentions: CKRS planning was performed using Multiplan ver. 4.0 (Accuray Inc.) and ray-tracing algorithm with a fixed cone (5-60 mm). In addition, CKRS was delivered to patients using CyberKnife ver. 4.0. A total 48-60 Gy was delivered in 3-4 fractions over the course of 3-11 days. Standard dose of CKRS for lung tumor in our institute is 54 Gy for 3 fractions. However, we changed this dose fractionation scheme, if tumor located near rib, skin, airway, esophagus, heart, large vessel and brachial plexus. For example, we usually prescribed 60 Gy for 4 fractions if tumor located adjacent to chest wall and 54 Gy for 4 fractions if tumor abutted to chest wall. The dose was prescribed as a 76%-85% isodose line, covering at least 95% of the PTV. Dose constraints for organs at risk were based on the previous report by Timmerman [15]. For 4 fractionated CKRS, we applied dose constraints of mid-value of 3 and 5 fractionated regimen (Table 1). Fig. 3 shows example of dose volume histogram (DVH) of centrally located tumor and CT images before and after CKRS.


Clinical outcome of fiducial-less CyberKnife radiosurgery for stage I non-small cell lung cancer.

Jung IH, Song SY, Jung J, Cho B, Kwak J, Je HU, Choi W, Jung NH, Kim SS, Choi EK - Radiat Oncol J (2015)

DVH and example of case. (A) DVH. (B) CT image, before treatment. (C) CT image, 1 month after CKRS. After delivery of 60 Gy for 4 fractions, we checked chest CT. This figure showed partially responded tumor after CKRS. (D) CT image, 5 months after CKRS. After 5 months, asymptomatic radiation pneumonitis occurred. (E) CT image, 11 months after CKRS. After 11 months, radiation fibrosis was observed without any symptom. (F) CT image, 24 months after CKRS. Until last follow-up, tumor did not progress with radiation change. DVH, dose volume histogram; CT, computed tomography; CKRS, CyberKnife radiosurgery.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4493433&req=5

Figure 3: DVH and example of case. (A) DVH. (B) CT image, before treatment. (C) CT image, 1 month after CKRS. After delivery of 60 Gy for 4 fractions, we checked chest CT. This figure showed partially responded tumor after CKRS. (D) CT image, 5 months after CKRS. After 5 months, asymptomatic radiation pneumonitis occurred. (E) CT image, 11 months after CKRS. After 11 months, radiation fibrosis was observed without any symptom. (F) CT image, 24 months after CKRS. Until last follow-up, tumor did not progress with radiation change. DVH, dose volume histogram; CT, computed tomography; CKRS, CyberKnife radiosurgery.
Mentions: CKRS planning was performed using Multiplan ver. 4.0 (Accuray Inc.) and ray-tracing algorithm with a fixed cone (5-60 mm). In addition, CKRS was delivered to patients using CyberKnife ver. 4.0. A total 48-60 Gy was delivered in 3-4 fractions over the course of 3-11 days. Standard dose of CKRS for lung tumor in our institute is 54 Gy for 3 fractions. However, we changed this dose fractionation scheme, if tumor located near rib, skin, airway, esophagus, heart, large vessel and brachial plexus. For example, we usually prescribed 60 Gy for 4 fractions if tumor located adjacent to chest wall and 54 Gy for 4 fractions if tumor abutted to chest wall. The dose was prescribed as a 76%-85% isodose line, covering at least 95% of the PTV. Dose constraints for organs at risk were based on the previous report by Timmerman [15]. For 4 fractionated CKRS, we applied dose constraints of mid-value of 3 and 5 fractionated regimen (Table 1). Fig. 3 shows example of dose volume histogram (DVH) of centrally located tumor and CT images before and after CKRS.

Bottom Line: Eight patients died due to cancer progression.The results showed that fiducial-less CKRS shows comparable local tumor control and survival rates to those of LINAC-based SABR or CKRS with a fiducial marker.Thus, fiducial-less CKRS using Xsight lung tracking system can be effectively and safely performed for patients with medically inoperable stage I non-small cell lung cancer without any risk of procedure-related complication.

View Article: PubMed Central - PubMed

Affiliation: Department of Radiation Oncology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.

ABSTRACT

Purpose: To evaluate the treatment results in early stage non-small cell lung cancer patients who have undergone fiducial-less CyberKnife radiosurgery (CKRS).

Materials and methods: From June 2011 to November 2013, 58 patients underwent CKRS at Asan Medical Center for stage I lung cancer. After excluding 14 patients, we retrospectively reviewed the records of the remaining 44 patients. All analyses were performed using SPSS ver. 21.

Results: The median age at diagnosis was 75 years. Most patients had inoperable primary lung cancer with a poor pulmonary function test with comorbidity or old age. The clinical stage was IA in 30 patients (68.2%), IB in 14 (31.8%). The mean tumor size was 2.6 cm (range, 1.2 to 4.8 cm), and the tumor was smaller than 2 cm in 12 patients (27.3%). The radiation dose given was 48-60 Gy in 3-4 fractions. In a median follow-up of 23.1 months, local recurrence occurred in three patients (2-year local recurrence-free survival rate, 90.4%) and distant metastasis occurred in 13 patients. All patients tolerated the radiosurgery well, only two patients developing grade 3 dyspnea. The most common complications were radiation-induced fibrosis and pneumonitis. Eight patients died due to cancer progression.

Conclusion: The results showed that fiducial-less CKRS shows comparable local tumor control and survival rates to those of LINAC-based SABR or CKRS with a fiducial marker. Thus, fiducial-less CKRS using Xsight lung tracking system can be effectively and safely performed for patients with medically inoperable stage I non-small cell lung cancer without any risk of procedure-related complication.

No MeSH data available.


Related in: MedlinePlus