Presentation on theme: "Pulmonary Stereotactic Ablative Radiotherapy: Current Implementation and Future Directions CTOP Conference 2014 Philip Schaner M.D., Ph.D."— Presentation transcript:
Pulmonary Stereotactic Ablative Radiotherapy: Current Implementation and Future Directions CTOP Conference 2014 Philip Schaner M.D., Ph.D
I have no conflicts of interest to report
Definition of Stereotactic Body Radiotherapy Method of delivering external beam radiotherapy (EBRT) Particles (proton) or photon Dose per Fraction: at least equivalent to radical doses in conventional fractionation: 5 – 34 gray (Gy) [ Conventional Fractionation: 1.8 – 2 Gy] Accurately delivers EBRT with a high degree of conformality Spatial and Temporal resolution of target and organs at risk Maintenance of high spatial targeting accuracy throughout the entire treatment Immobilization High frequency position monitoring through integrated image guidance Respiratory Motion Management Few fractions: Nomenclature: Stereotactic ablative radiotherapy (SABR) Stereotactic body radiotherapy (SBRT)
Subset of NSCLC appropriate for SBRT Stage I subset: typically < 5 cm in maximal dimension Not invading outside the chest (can be touching pleura) Not invading into lobar bronchus Minimal associated lung collapse Mass well delineated
Subset of NSCLC appropriate for SBRT Mass too large, invading into nearby structures Primary acceptable but nodal disease present
Treatment Planning Highly conformal dose distribution with rapid dose fall off Maximally spare adjacent organs Low dose spill High dose spill
Accurate Delivery Target localization Lung cancer is a moving target….
4D Treatment Delivery Patient Breaths Normally – Control when XRT is on
Multi-institutional Phase II Data: RTOG 0236 Inclusion: NSCLC T1 or T2, N0,M0 Peripheral: > 2 cm from proximal bronchial tree Medically inoperable: FEV1 <40%, DCLO < 40% Methodology: All tumors received 18 Gy x 3 fractions (54 Gy) Accrual: 55 pts Timmerman et al. JAMA 2010 Clinical
RTOG 0236 Results: Timmerman et al. JAMA 2010 Local control: 3 yr = 97.3% (one T2 tumor progressed in-field) Regional control: 3 yr = 87.2% (2 nodal failures, both around 35 months post SABR) Distant Failure: 3 yr T1: 14.7% 3 yr T2: 47% Toxicity: 12.7% Grade 3 toxicity 3.6% Grade 4 toxicity Clinical
Treatment of oligometastatic disease: Stage IV cancer with ≤ 5 metastatic lesions Inclusion: Any primary tumor except germ cell, leukemia, lymphoma Max cumulative tumor diameter < 7 cm Extrathoracic disease allowed: low burden, potentially treatable with 1 st or 2 nd line standard therapy Adequate lung function: FEV1 >40%, DCLO >40% Methodology: Dose escalation to 20 Gy x 3 fractions (60 Gy) Accrual: 38 pts => 63 lesions Rusthoven et al. JCO 2009 Clinical Multi-institutional phase I/II trial of stereotactic body radiation therapy for lung metastases
Results: Local control: 2 yr = 96% Patient characteristics Clinical Rusthoven et al. JCO 2009 Toxicity: Grade 3: 8% Grade 4-5: 0%
Areas of Investigation What is the appropriate SABR dose for peripheral lesions?
Areas of Investigation RTOG 0915 interim outcomes: N=94 Median FU 20.6 months No significant difference with respect to toxicity in both arms: 9.8% 34 Gy vs 13.3% 48 Gy > Gr 3 toxicities. Local Control at 1 yr 97% both arms. Winner? Need longer term follow up Local Failure increases over time in many series, one year is not enough follow up.
What is the appropriate SABR dose for centrally located lesions? Areas of Investigation
Measuring SABR against Surgery Stage IA NSCLC Peripheral lesion ARM 1: Anatomical surgical resection with LN dsxn ARM 2: SABR 20 Gy x 3 12 Gy x 5 FOLLOWUPFOLLOWUP ROSEL Trial (Netherlands) Terminated due to poor accrual Areas of Investigation
Measuring SABR against Surgery Stage I NSCLC < 4 cm Good surgical candidate FEV1 > 40% pred DLCO > 40% pred Post-op predicted FEV1 > 30% ARM 1: Lobectomy or pneumonectomy ARM 2: SABR using Cyberknife Peripheral: 20 Gy x 4 Central: 15 Gy x 4 FOLLOWUPFOLLOWUP Lung Cancer STARS trial: phase III, endpoint 3 yr OS Areas of Investigation
Measuring SABR against Surgery Histological confirmation NSCLC and confirmation N2/N3 negative lymph nodes T < 3 cm Peripheral High risk for surgery Major FEV1 ≤50% pred DLCO ≤50% pred Minor Age ≥75 years FEV % pred DLCO 51-60% pred ARM 1: Sublobar Resection ± Brachytherapy (SR) ARM 2: Stereotactic Body Radiation Therapy (SBRT) 18 Gy X 3 = 54 Gy FOLLOWUPFOLLOWUP ACOSOG Z4099/RTOG 1021 Phase III Trial Opened June 2011 Areas of Investigation
Combining radiofrequency ablation with SABR UNM: RFA combined with SABR for large lung tumors T2-4N0 > 3 cm; N1-3 if M1 eligible 40 Gy/5 fractions escalating to 50 Gy/5 fractions f/b RFA procedure Areas of Investigation Using SBRT as a boost for Stage II/III NSCLC U Kentucky: Stage IIA – selected III-B 59.4 Gy chemoradiotherapy => if residual disease: boost 10 Gy x 2 (peripheral) Proton vs Photon SBRT SBRT combined with chemotherapy Maintenance chemotherapy vs consolidative SBRT for Stage IV NSCLC UTSW: 1 st line chemo (no biologics) => up to six discrete extracranial lesions U Kentucky: T1-T3N0 NSLC => SBRT then adjuvant cisplatin + docetaxel or pemetrexed