Usefulness of Interferon-gamma Release Assay in Diagnosing Pulmonary Nodules

Study Overview
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Brief Summary
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Among the causes of the solitary pulmonary nodule (SPN), benign causes including tuberculosis was noted on 15 to 60 percents in various studies. Although the characteristics of chest imaging is helpful in diagnosis and percutaneous needle biopsy for pulmonary nodule has been represented high diagnostic yield in many reports, but still surgical biopsy has been needed in definite diagnosis of pulmonary nodules in many cases. The aim of this study is to evaluate the usefulness of interferon-gamma release assay in addition to the percutaneous needle biopsy, in diagnosis of pulmonary nodules.

Detailed Description
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Among the patients who failed to diagnosis by percutaneous needle biopsy and needed to have Surgical biopsy, thirty percents of the patients were diagnosed as benign nodules and about six percents were diagnosed as tuberculosis in Seoul National University Hospital during 2007-2008. The investigators want to know whether conducting an interferon-gamma release assay in addition to percutaneous needle biopsy is helpful in diagnosis of lung nodules.

Official Title
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Usefulness of Interferon-gamma Release Assay in Diagnosing Pulmonary Nodules

Conditions
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Solitary Pulmonary Nodule

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age> 18 years in patients with solitary pulmonary nodule who had percutaneous needle biopsy for diagnosis of lung nodule Exclusion Criteria: patients who do not agree the study enrollment

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| IGRA in solitary pulmonary nodules<br>Inpatients who undergo percutaneous needle biopsy for diagnosis of pulmonary nodules in Seoul National University hospital for six months are going to be included. Patients who are not tolerable for PCNB or do not agree the enrollment of study will be excluded. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Positive rate of the interferon-gamma release assay | the result of the interferon-gamma release assay is reported in three different categories as positive, negative or indeterminate. We want to know whether the positive rate of the interferon-gamma release asssay would be significantly different according to the pathologic diagnosis of lung nodules confirmed by percutaneous needle biopsy. | within 36hrs after blood sampling | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Positive rate of the Tuberculin skin test | We will conduct Tuberculin skin test and evaluate the whether the positive rate of the Tuberculin skin test would be different according to the pathologic diagnosis of lung nodules confirmed by percutaneous needle biopsy. | 48hours after tuberculin skin test |