Intratumoral chemotherapy as an adjunct to endobronchial brachytherapy
7591 Background: NSCLC patients (pts) with clinically significant endobronchial obstruction have a poor prognosis and quality of life in both locally advanced and metastatic stages of disease. Radiation therapy (RTx) in conjunction with chemotherapy (CTx) improves survival compared to either modality alone but produces greater toxicity and morbidity. Significant clinical benefit with respect to disease management and quality of life could be realized with improved methods for controlling obstructing endobronchial lesions. The hypothesis for this study is that optimal clinical control of endobronchial lesions can be achieved by intratumoral injection of a drug with both clinical activity against NSCLC and synergy with RTx. Cisplatin (CPt), an active agent in NSCLC and a known radiosensitizer is an ideal drug for this objective. Thus, the goal of this exploratory study was to determine the clinical efficacy and tolerance to intratumoral CPt injection in combination with HDR brachytherapy (BTx) in NSCLC patients with obstructing endobronchial lesions. Methods: NSCLC pts (n=16) with > 75% endoluminal obstruction of a main or lobar airway were evaluated. Intratumoral CTx consisted of CPt (1 mg/ml; 0.5–2.0 ml/session) injected into the entire visible tumor through a flexible 21 gauge needle through the bronchoscope. BTx was given as 500 cGy/session at one cm diameter for 4 sessions concomitant with CTx. Results: All pts completed the entire 4 sessions of planned local therapy. There was complete resolution of injected lesions in 14/16 pts confirmed bronchoscopically and cytologically. In the other 2 pts, necrotic tissue occupying < 10 and 20% of the airway, cytologically negative for tumor was seen. There were no adverse events or complications related to bronchoscopy or local CTx. Conclusions: The results of this study demonstrate that intratumoral administration of CPt, as an adjunct to endobronchial BTx for the management of endobronchial obstructing lesions in patients with NSCLC is safe and effective. This approach offers the possibility of superior local tumor control while reducing toxicity to normal lung and esophagus as compared to conventional external beam radiation therapy modalities. Further studies evaluating the impact of this approach on survival and quality of life are warranted. No significant financial relationships to disclose.