ARRS 2022 Abstracts


E1310. Direct Macroscopic Invasion of the Pulmonary Veins by Pulmonary Masses: An Institutional Image-Based Review of a Rare Type of Tumor Thrombus
  1. Abtin Jafroodifar; SUNY Upstate Medical University
  2. Ryan Thibodeau; SUNY Upstate Medical University
  3. Sahir Quareshi; SUNY Upstate Medical University
  4. Zaid Siddique; SUNY Upstate Medical University
  5. Paul Depew; SUNY Upstate Medical University
  6. Ernest Scalzetti; SUNY Upstate Medical University
  7. Swati Deshmane; SUNY Upstate Medical University
Tumor thrombus refers to the direct invasion of vasculature by tumoral extension. This phenomenon has been classically referred to in the context of solid abdominal or pelvic organs cancers, such as renal cell carcinoma invasion into the renal vein or IVC. The same concept occurs in the chest with pulmonary neoplasms; however, this is less reported and seldomly appropriately recognized. Through this exhibit, we hope to introduce the concept of pulmonary tumor thrombus and macroscopic invasion into pulmonary vasculature with hopes that radiologists will be comfortable recognizing this phenomenon and appropriately reporting it.

Educational Goals / Teaching Points
This exhibit will first present relevant pulmonary, cardiac, and mediastinal anatomy that is relevant in identifying tumor thrombi. Then we will explore the rare phenomenon of direct macroscopic pulmonary vein invasion by pulmonary masses using multiple image-based cases from our institution. A review of pertinent imaging findings related to tumor thrombus on US, CT, MRI, PET/CT, angiography, and 3D-cinematic renderings will be presented, with a focus on 3D segmentation, which helps visualize tumor tracts. Furthermore, an image-based analysis of pulmonary masses directly invading into the pulmonary veins will be presented using cases from our institution. An easy-to-follow checklist to correctly identify tumor invasion using imaging will be presented, including analysis of vein caliber and contour, lack of luminal opacification, examining for a left atrial mass, and inspection of pericardial spaces.

Key Anatomic/Physiologic Issues and Imaging Findings/Techniques
The lungs remain to be a common site for metastatic disease for many neoplasms due to the hematogenous spread of cancer cells and the highly vascular architecture of the lungs. Less considered is the direct macroscopic invasion of pulmonary vasculature by cancers, namely pulmonary subtypes, with the slow growth towards the cardiac atria. Often this phenomenon is described as venothrombotic embolism, but this is categorically incorrect. This concept falls under the umbrella of tumor thrombus and management may be different than just anticoagulation or thrombectomy. In our institution, using 3D segmentation and cinematic-rendering has helped us identify more cases where pulmonary cancers have directly invaded into vasculature, with some cases extending to the left atrium.

Direct macroscopic tumor invasion into pulmonary vasculature is a less-described concept and therefore is less often identified by radiologists and trainees. It is important to review this concept in hopes for more accurate reporting and improved patient management and outcomes.