Introduction: This is a preliminary report of an ongoing prospective bimodality lung cancer surveillance trial for high-risk patients. Bimodality surveillance incorporates autofluorescence bronchoscopy (AFB) and spiral CT (SCT) in high-risk patients as a primary lung cancer surveillance strategy, based entirely on risk factors. AFB was used for surveillance and findings were compared with conventional sputum cytology (CSC) for the detection of malignancy and premalignant central airway lesions.
Eligibility: For eligibility, patients were required to have at least two of the following risk factors: 1) > 20 pack year history of tobacco use, 2) asbestos-related lung disease on chest radiograph, 3) COPD with an FEV-1 < 70% of predicted, and 4) prior aerodigestive cancer treated with curative intent, with no evidence of disease for > 2 years. All eligible patients under went AFB, a low dose SCT of the chest without contrast, and a sputum sample was collected for cytology. Bronchoscopy biopsy findings were correlated with sputum cytology results, SCT-detected pulmonary nodules and surveillance-detected cancers. To date, 186 have been enrolled with 169 completing the surveillance procedures.
Results: 402 patients registering at Roswell Park Cancer Institute (RPCI) were evaluated with spirometry, chest x-ray, history and physical examination, of which 207 were deemed eligible for the study. 13 lung cancers (7%) were detected in the 169 subjects who have completed all three surveillance studies to date. Premalignant changes were common and 66% of patients had squamous metaplasia or worse. CSC missed 100% of the dysplasia and 68% of the metaplasia detected by AFB, and failed to detect any cases of carcinoma or carcinoma in situ in this patient cohort. CSC exhibited 33% sensitivity and 64% specificity for the presence of metaplasia. Seven of 13 (58%) lung cancers were stage Ia or less, including 3 patients with squamous cell carcinoma. Patients with peripheral pulmonary nodules identified on SCT of the chest were 3.16 times more likely to exhibit premalignant changes on AFB (p < 0.001).
Conclusion: Bimodality surveillance will detect central lung cancer and premalignancy in patients with multiple lung cancer risk factors, even when conventional sputum cytology is negative. In high-risk patients, AFB should be considered, regardless of sputum cytology findings.
- auto-fluorescence bronchoscopy
- chronic obstructive pulmonary disease
- risk assessment
- spiral CT
- white light bronchoscopy