We thank Dr. Lopez-Encuentra et al for their thoughtful and insightful comments. As described in the “Materials and Methods” section, we included only stage I (T1–2N0M0) non-small cell lung cancer patients whose TNM codes were completely recorded in the California Cancer Registry. The T descriptors of all the patients in the study were coded by one of the three extent of disease (EOD) codes: 10, 20, or 40 with no overlap or missing codes indicating excellent internal consistency. The EOD codes and N descriptors were generally abstracted from pathology and/or radiology reports so they can be either pathologically or clinically staged. This limitation was discussed in the article. The Surveillance, Epidemiology, and End Results EOD codes are hierarchically arranged so if a tumor contains both EOD-20 (mainstem bronchus ≥ 2 cm from carina) and EOD-40 (visceral pleura invasion, hilar atelectasis, or obstructive pneumonitis) criteria, only EOD-40 will be coded. We agree with Dr. Lopez-Encuentra et al that we cannot separate the three criteria (visceral pleura invasion, hilar atelectasis, or obstructive pneumonitis) individually, nor can we know how many EOD-40 cases also had EOD-20 criteria, and this is a study limitation. However, we demonstrated that T descriptors coded as T2 due to EOD-20 criteria alone (mainstem bronchus ≥ 2 cm from carina) are infrequent (5.7%).