Importance of timing for thoracic irradiation in the combined modality treatment of limited-stage small-cell lung cancer. The National Cancer Institute of Canada Clinical Trials Group.

PURPOSE: The importance of the timing of thoracic irradiation (TI) in the combined modality therapy of limited-stage small-cell lung cancer (SCLC) was assessed in a randomized trial. METHODS: All 308 eligible patients received cyclophosphamide, doxorubicin, and vincristine (CAV) alternating with etoposide and cisplatin (EP) every 3 weeks for three cycles of each chemotherapy regimen. Patients randomized to early TI received 40 Gy in 15 fractions over 3 weeks to the primary site concurrent with the first cycle of EP (week 3), and late TI patients received the same radiation concurrent with the last cycle of EP (week 15). After completion of all chemotherapy and TI, patients without progressive disease received prophylactic cranial irradiation (25 Gy in 10 fractions over 2 weeks). RESULTS: Although complete remission rates were not significantly different between the two arms, progression-free survival (P = .036) and overall survival (P = .008) were superior in the early TI arm. Patients in the late TI arm had a higher risk of brain metastases (P = .006). CONCLUSION: The early administration of TI in the combined modality therapy of limited-stage SCLC is superior to late or consolidative TI.

Predicting the response of obstructive endobronchial tumors to photodynamic therapy.

To investigate the usefulness of bronchoscopic examination, computerized tomography (CT), and radionuclide quantitative ventilation-perfusion lung scan to determine the response of patients with obstructive endobronchial tumors to photodynamic therapy (PDT), the findings in 24 patients treated with PDT were analyzed. PDT was found to be most effective when the tumor was bronchoscopically polypoid in appearance, with little or no submucosal invasion or peribronchial extension seen on CT scans. With increasing submucosal and/or peribronchial extension, the immediate response to treatment was poorer. Patients who had 50% or more of the airway obstruction due to mucosal tumor had no evidence of local tumor recurrence for a median interval of 22 weeks after treatment. In patients with predominant submucosal and/or peribronchial tumor, the duration of response was 7 weeks. Response to treatment did not correlate with the degree of airway obstruction. CT provided valuable information regarding the extent of the peribronchial involvement and airway distortion, which was often underestimated by bronchoscopy alone. Absent perfusion or reduction of regional perfusion out of proportion to ventilation on scintigraphy in the involved lung zone was found to be associated with extensive peribronchial involvement and a poor outcome. The authors conclude that the addition of CT and radionuclide quantitative ventilation-perfusion lung scan to bronchoscopic examination is useful in predicting the response of patients with obstructive endobronchial tumors to PDT.

Laser treatment of obstructive endobronchial tumors: factors which determine response.

To investigate whether computerized tomography (CT) and radionuclide quantitative ventilation-perfusion lung scan add any useful information to a carefully performed endoscopic examination in determining the response of patients with obstructive endobronchial tumors to laser treatment, the findings in 40 patients treated with photodynamic therapy (PDT) or the Nd:YAG laser were analysed. Endoscopic laser treatment was found to be most effective when the tumor was polypoid in appearance bronchoscopically, with little or no submucosal invasion or peribronchial extension seen on CT. When bronchoscopy and CT showed increasing submucosal and/or peribronchial disease, the immediate and long-term response to treatment was poorer. CT provided valuable information regarding the extent of the peribronchial involvement and airway distortion which were often underestimated by bronchoscopy alone. Reduction of regional perfusion out of proportion to ventilation on scintigraphy in the involved lung zone was found to be associated with extensive peribronchial involvement. We conclude that the addition of CT and radionuclide quantitative ventilation-perfusion lung scan to bronchoscopic examination is useful in predicting the response of patients with obstructive endobronchial tumors to laser treatment. Whether PDT or YAG laser is more effective in relieving endobronchial obstruction by tumor awaits a randomized controlled trial.