Hilar Mass – Primary Lung Cancer

Table of Contents

Table of Contents

Lauren Brown, MD
Expert reviewer: David Godwin, MD (University of Washington, Department of Radiology)


  1. Identify key characteristics that differentiate a hilar mass due to primary lung cancer from other causes.

Teaching Instructions

Plan to spend 5-10 minutes familiarizing yourself with the animations of the PowerPoint and the key findings of this chest X-ray.

Present the image either by expanding the window (bottom right) in a browser or downloading the PowerPoint file (recommended for optimal function).  Have the image pulled up in presenter mode before learners look at the screen to avoid revealing the diagnosis.  Ask a learner to provide an overall interpretation.  Then advance through the animations to prompt learners with key questions and reveal the findings, diagnosis, and teaching points.  

CXR Interpretation: Right hilar pulmonary mass with right upper lobe volume loss suggesting at least partial bronchial obstruction centrally.

Diagnosis: Primary Squamous Cell Carcinoma of the Lung.

Teaching: Red arrows point to the right hilar mass. This can be identified as intra-pulmonary because of its ill-defined margins; intrapulmonary processes grow into the lung, creating a gradual and thus ill-defined margin. Processes outside of the lung abut the pleura, creating a crisp margin

There is a partial upper lobe collapse from compression of the R bronchus.  Signs of volume loss (light green arrows) include upward displacement of the minor fissure, “peaking” of the right hemidiaphragm, and rightward displacement of the trachea. The remaining right upper lobe remains lucent, so there is not complete upper lobar collapse

Presentation Board

Take Home Point

  1. Intrapulmonary masses will have ill-defined margins, whereas extrapulmonary masses (i.e. mediastinal or pleural masses) abut the pleura which creates sharp margins.
  2. Signs of volume loss include displacement of fissures, tracheal deviation, and peaking of the ipsilateral hemidiaphragm.


McLoud, Boiselle, & Boiselle, Phillip M. (2010). Thoracic radiology : The requisites (2nd ed., Requisites in radiology). Philadelphia: Mosby/Elsevier.

Brandon Fainstad


Comment on this article