Tumoral cavitation in patients with non-small-cell lung cancer treated with antiangiogenic therapy using bevacizumab

RATIONALE AND OBJECTIVES To investigate the frequency and radiographic patterns of tumoral cavitation in patients with non-small cell lung cancer (NSCLC) treated with bevacizumab, and correlate the imaging findings with the pathology, clinical characteristics and outcome. MATERIALS AND METHODS Seventy-two patients with NSCLC treated with bevacizumab therapy were identified retrospectively. Baseline and follow-up chest computed tomography scan were reviewed to identify tumoral cavitation and subsequent filling in of cavitation. Radiographic cavitation patterns were classified into 3 groups. The clinical and outcome data were correlated with cavity formation and patterns. RESULTS Out of 72 patients, 14 patients developed cavitation after the initiation of bevacizumab therapy (19%; median time to event, 1.5 months; range 1.0-24.8 months). Three radiographic patterns of tumoral cavitation were noted: (1) development of cavity within the dominant lung tumor (n = 8); (2) development of non-dominant cavitary nodules (n = 3); and (3) development of non-dominant cavitary nodules with adjacent interstitial abnormalities (n = 3). Eleven patients (79%) demonstrated subsequent filling in of cavitation (the time from the cavity formation to filling in; median 3.7 months; range 1.9-22.7 months). No significant difference was observed in the clinical characteristics, including smoking history, or in the survival between patients who developed cavitation and those who did not. Smoking history demonstrated a significant difference across 3 radiographic cavitation patterns (P = 0.006). Hemoptysis was noted in 1 patient with cavity formation and 4 patients without, with no significant difference between the 2 groups. CONCLUSION Tumoral cavitation occurred in 19% in patients with NSCLC treated with bevacizumab and demonstrated 3 radiographic patterns. Subsequent filling in of cavitation was noted in the majority of cases.