PURPOSE: It is widely held that a Lung nodule which remains stable for 2 years is benign. This is based on data that is currently being reconsidered. Our hypothesis is that such nodules are in fact benign.
METHODS: All patients seen at the Oklahoma City VA thoracic oncology clinic between 1999 and 2007 were evaluated. Those with a radiographically stable lung nodule after a 2 year follow up were evaluated. Imaging beyond the 2 year stability period, as well as the patients’ clinical outcome, were reviewed.
RESULTS: A total of 1165 patients were evaluated in our clinic; 35(3%) patients had nodules that were radiographically stable over 2 years at which time they were deemed to have a benign lesion. Of these, one patient, a nursing home resident, died, and another was lost to follow up before further imaging could be obtained. The remaining 33 patients, with a total of 35 nodules were included in our analysis. All were males, with an average age of 63±12 years. Thirty two patients were smokers with an average of 51±30 pack-years. Lesions’ size ranged from 0.5 to 4.5 cm(mean 1.6±0.9 cm). Most lesions occurred in the right upper lobe (34%) and the left upper lobe (26%). Beyond the 2 years stability period, follow up imaging averaged 1.5±1.4 years (11 patients had a CXR, 21 had chest CT and one patient had both). Of the 35 nodules, only one (2.9%, 95% confidence interval 0.09 to 17.7%) increased in size from 2.4 to 3 cm. Its doubling time was 1719 days, suggesting a benign etiology. 32 patients are still alive 2.3 years beyond the follow up period. One patient, whose lesion remained stable, died in a nursing home 3.4 years after the initial stability period.
CONCLUSION: Our data suggests that if a lung nodule is stable over a two year period, it is likely to be benign, and further evaluation is not warranted.
CLINICAL IMPLICATIONS: This Study will help clinician with the follow up of lung nodules.
DISCLOSURE: Nadim Daher, No Financial Disclosure Information; No Product/Research Disclosure Information