In this issue of CHEST (see page 881), Bandi et al2present yet another application for ultrasound use by pulmonologists: the detection of chest wall invasion by lung tumors. To understand the importance of this issue, we must first recall the relevant features of the TNM staging scheme of non-small cell lung cancer.3A tumor mass is considered T2 if it does not extend beyond the visceral pleural. Invasion of the parietal pleura or chest wall upstages the mass to T3. Although chest wall invasion by lung tumors does not prevent curative surgical resection, it calls for more detailed preoperative planning to determine the best surgical approach, extent of resection, and possible use of neoadjuvant radiation or chemotherapy.4–5 Currently, physical examination, chest CT and, to a lesser degree, MRI are relied on to make this determination of chest wall invasion. Ultrasound may theoretically be a superior radiographic modality given its ability to closely assess the relationship between a lung mass and surrounding soft tissue in a real-time dynamic setting.6 Bandi et al,2 in fact, found ultrasound to be superior to CT in the assessment of chest wall invasion with higher sensitivity, accuracy, and negative predictive value (89% vs 42%, 91% vs 83%, and 95% vs 80%, respectively). Unfortunately, ultrasound had more false-positive results than CT, resulting in a lower specificity and positive predictive value (95% vs 100%, 88% vs 100%, respectively).