Author of

• 16637

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  P1.03 - Poster Session with Presenters Present (ID 455)

  • Event: WCLC 2016
  • Type: Poster Presenters Present
  • Track: Radiology/Staging/Screening
  • Presentations: 1
  • Moderators:
  • Coordinates: 12/05/2016, 14:30 - 15:45, Hall B (Poster Area)

  • 16713

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    P1.03-076 - Nodal Staging of Patients with Pulmonary Malignancies - The Predictive Value of Different Patterns of Mediastinal 18FDG-PET Activity (ID 5928)

    14:30 - 14:30  |  Author(s): A.-. Markewycz
    • Abstract

    Background:
    In patients with pulmonary malignancies, 18FDG uptake in mediastinal nodes is a sensitive but non-specific indicator of metastatic disease. The pattern of tracer uptake may improve the predictability of such findings.
    
    Methods:
    Aim: To retrospectively i) compare 18FDG-PET scans and EBUS findings in patients with documented pulmonary malignancies; and, ii) compare the pattern of 18FDG uptake in mediastinal nodes in patients with / without documented mediastinal node metastases. Methods: 62 patients with documented pulmonary malignancies underwent 18FDG-PET scintigraphy followed by EBUS within the ensuing 3 weeks. One-two nodes were assessed in each patient, determined by 18FDG-PET findings and accessibility of the FDG-positive nodes. The mediastinal nodal status from each procedure was compared.
    
    Results:
    Results: EBUS resulted in mediastinal nodal status downgrading in 25 (40%) patients. No upgrading was noted. Downgrading most likely occurred when there several non-enlarged lymph nodes of similar 18FDG-avidity distributed randomly and bilaterally in the mediastinum, often with bilateral hilar uptake (17 of 25 patients). Further, only 2 of 19 patients exhibiting such a pattern of mediastinal tracer distribution were found to have lymph node metastases (10%), and both had metastatic disease elsewhere on the PET scan. 21 of 23 patients with positive EBUS findings demonstrated discrete 18FDG-avid lymph nodes ipsilaterally, with minimal-to-no 18FDG-avid nodes contralaterally. EBUS findings in 14 (23%) patients were inconclusive, despite multiple sampling. Enlarged, rounded lymph nodes with avid FDG uptake (SUV>4) were also more likely to harbour metastatic disease. Conversely, a Hounsfield unit of >55 was associated with benign disease.
    
    Conclusion:
    Conclusion: The pattern of mediastinal 18FDG uptake was highly predictive of metastatic disease, and may circumvent the need for EBUS evaluation. Prospective analysis of these parameters will be undertaken.