Author of

• 11905

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  P2.20 - Poster Session 2 - Early Detection and Screening (ID 173)

  • Event: WCLC 2013
  • Type: Poster Session
  • Track: Imaging, Staging & Screening
  • Presentations: 1
  • Moderators:
  • Coordinates: 10/29/2013, 09:30 - 16:30, Exhibit Hall, Ground Level

  • 11911

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    P2.20-006 - Autoantibodies to a panel of lung cancer-associated antigens can provide significant discrimination between malignant and non-malignant lung nodules (ID 1902)

    09:30 - 09:30  |  Author(s): L.J. Peek
    • Abstract

    Background
    EarlyCDT®-Lung, a clinical blood test that detects autoantibodies to lung cancer-associated antigens, has shown high specificity in case-control validation studies[(1)].The performance of this test in routine clinical use was audited in an initial series of 1612 patients tested by EarlyCDT-Lung who signed HIPAA authorization permitting disclosure of their health information to Oncimmune®; the reported specificity and sensitivity (91%/41%) of the test was as predicted by case-control studies[(2)].

    Methods
    A prospective audit was conducted of 423 individuals known to have a lung nodule for whom lung cancer-associated autoantibodies were measured by EarlyCDT-Lung. Physicians were contacted following patient testing by EarlyCDT-Lung to determine whether a cancer diagnosis had been made or a pulmonary nodule identified by imaging. Imaging and pathology reports were reviewed. This report focuses on patient outcomes at 6 months following EarlyCDT-Lung, and specifically on the 318/423 individuals for whom a lung nodule was detected prior to EarlyCDT-Lung testing. The EarlyCDT-Lung panel was modified in November 2010 from a 6 autoantibody (AAB) panel to 7AAB to improve specificity of the test[(3)] ; there were 152/318 individuals with nodules who had the 6AAB test and 166/318 who had the 7AAB test. Analyses comparing EarlyCDT-Lung results by malignant and non-malignant nodules were made using chi-squared tests.

    Results
    Of the 423 individuals with nodules, there were 77 patients diagnosed with a lung cancer, and 346 were deemed to have a non-malignant nodule; 32/77 and 76/346 were positive for EarlyCDT-Lung, respectively (p=0.0004). Overall, this represented a 2-fold increased incidence of lung cancer with a positive result. Of the 318 individuals with lung nodules known prior to testing by EarlyCDT-Lung, the number of positive tests were 27/62 lung cancers and 43/256 non-malignant nodules (p= 0.000005); therefore, a positive result reflected a 2.7-fold increased incidence in this group. Considering nodule size, there was no difference for nodules <8mm, but the number of lung cancers in this group was small at only n=3. For nodules between 8-20mm and ≥20mm, a positive EarlyCDT-Lung test was statistically more likely to signify a lung cancer (p=0.06 & p=0.002, respectively; p=0.00008 combined). When only the 7AAB test was assessed, which has greater specificity, for 8-20mm and ≥20mm nodules a positive EarlyCDT-Lung test remained significantly more likely to indicate a lung cancer even though the numbers in each group were relatively small, n=58 & n=52, respectively (p=0.01 & p=0.004, respectively; p=0.0001 combined). For the 7AAB test overall and also for indeterminate nodules (8-20mm), a positive result represented a 3.5-fold increased incidence of lung cancer.

    Conclusion
    EarlyCDT-Lung positivity reflects a statistically significant increased risk of malignancy for lung nodules ≥8mm. This varies from 2-fold to 3.5-fold depending on nodule size. These data confirm that EarlyCDT-Lung adds to the armamentarium of the pulmonologist in assessing the risk of malignancy in nodules ≥8mm. More data are required for lung nodules <8mm size. References: (1) Boyle P, et al. Ann Oncol. 2011;22:383-389. (2) Jett JR, et al. J Thoracic Oncology 2012;7:S222. (3) Chapman CJ, et al. Tumor Biol. 201;33(5):1319-1326.