Consolidation therapy using cyberknife radiosurgery in NSCLC patients with low-volume residual disease upon completion of systemic therapy

Abstract

18213 Background: Pts with unresectable IIIB and IV NSCLC with PS 0–1 are usually treated with chemotherapy (CH) ± targeted therapy (TT) with overall survival (OS) improvement. Upon completion, standard of care is observation. Pts eventually progress within 9 to 12 months. If still in good PS, they are treated with salvage CH or TT; otherwise, they receive palliative care. We evaluated 12 patients with PR to initial therapy, found to have small volume residual disease (SVRD) defined as one or two sites to receive “consolidation” local therapy with Cyberknife Radisurgery (CRS). Methods: Since September 2006, 12 pts with NSCLC, stage IIIB unresectable (3) or IV (9), median age 64 (range 61–78), adenocarcinoma (7), squamous cell carcinoma(5), 9 males, all ECOG PS 0–1, were treated with induction CH (carboplatin/paclitaxel ± bevacizumab, cisplatin/gencitabine) with PR. CT/PET imaging showed SVRD. Eight patients had only one site; four had 2. These patients received CRS consolidative therapy to the following areas: lung-9, mediastinal node - 3, adrenal-2, liver-2. CRS dose depended on the disease site. Peripheral lung lesions - 54 Gy in 3 fractions (fx); medistinal lesions - 50 Gy in 4 fx; adrenal - 24 Gy in 3 fx and liver - 16 Gy. in 1 fx. The primary end point was efficacy (response rate, time to progression in or out of the radiosurgical fields, and OS) compared with historical matched controls. The secondary end point was safety and tolerability of CRS. Results: After a median follow up period of 65 days, all evaluable pts are still alive and without clinical or radiological (CT/PET) evidence of disease progression in or outside the sites of CRS. The treatment was well tolerated with no Grade 3–5 complications. PS remained 0–1 in all patients. Conclusions: Patients with advanced NSCLC benefit from systemic therapy with symptoms control and improved QoL and OS. Upon completion of therapy, observation is the current standard or care. Patients with good PS and SVRD tolerated CRS consolidation therapy remarkably well and may benefit with added symptoms control, improved TTP and even OS. At the June meeting efficacy and toxicity data of a projected population of 30+ patients, with a medial follow up of 8 months, will be presented. No significant financial relationships to disclose.