Solitary Pulmonary Nodule

From: Subject: Solitary Pulmonary Nodule Date: Wed, 3 Jun 2009 21:37:59 -0700 MIME-Version: 1.0 Content-Type: multipart/related; type="text/html"; boundary="----=_NextPart_000_01EB_01C9E493.90698650" X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.5579 This is a multi-part message in MIME format. ------=_NextPart_000_01EB_01C9E493.90698650 Content-Type: text/html; charset="Windows-1252" Content-Transfer-Encoding: quoted-printable Content-Location: http://www.acpmedicine.com/acp/newrxdx/rxdx/dxrx1404.htm Solitary Pulmonary Nodule

Solitary = Pulmonary=20 Nodule

Gerald W. Staton, Jr., M.D., F.A.C.P. Emory = University School of Medicine

Defin= ition/Key=20 Clinical Features
Diffe= rential=20 Diagnosis
Best = Tests
Best = Therapy
Best = References=20

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Definition/Key=20 Clinical Features

Round lesion ≤ 3 cm in diameter = surrounded by=20 lung=20
Lesions > 3 cm called masses=20
Evaluate to detect malignancy=20
- 10%=9670% are malignant
Of benign lesions, 80% are granulomas, 10%=20 hamartomas

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Differential = Diagnosis

Infectious Diseases

Granulomas=20

Fungal=20
Tuberculous

Parasites=20

Echinococcus=20
Dirofilaria

Neoplastic Diseases

Carcinoma=20
Solitary metastasis=20
Carcinoid=20
Hamartoma

Noninfectious, Nonneoplastic = Disorders

Bronchogenic cysts=20
Arteriovenous malformation=20
Intrapulmonary lymph node=20
Rounded atelectasis=20
Hematoma

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Best=20 Tests

Aids in Diagnosis of = Malignancy

History=20

Patient age=20
- < 45 yr: low risk=20
- > 60 yr: high risk
- Cigarette smoking=20
  - Never smoked: low risk
  - Current smoker: high risk=20

Lesion = Size=20

< 1.5 cm: low risk=20
≥ 2.3 cm: high risk

Pattern of Lesion Margin

Corona radiata (fine strands extending from = lesion):=20 high risk=20
Scalloped margins: intermediate risk=20
Smooth border: low risk

Calcification of Lesion=20

Stippled or eccentric calcification: high = risk=20
Laminated or central calcification: = granuloma=20
=93Popcorn=94 calcification: hamartoma =

Growth of Lesion=20

Old chest radiographs, CT scans reveal = stability or=20 growth=20
30% increase in diameter =3D doubling of = volume=20
Doubling in volume over > 1 mo and < 1 = yr=20 indicates malignancy=20
Stability for 2 years =3D benign in 65% =
Follow-up imaging every 3 mo for 1 yr, then = every 6 mo=20
- CT can detect changes in size within 30 = days=20

Noninvasive Diagnostic = Methods

CT Densitometry=20

Lesions with greater density more likely = benign=20
Lesion must be compared with a =93phantom=94 = for density=20 calibration=20
Cutoff points: 185=96264 Hounsfield = units=20

Contrast-Enhanced CT=20

Enhancement of lesion of > 20 Hounsfield = units=20
Sensitivity, 95%=96100%; specificity, = 70%=9693%=20

Positron Emission Tomography =

Differentiates benign from malignant = nodules=20
Sensitivity, 97%; specificity, 78%=20
False positives: infectious, inflammatory = lesions=20
False negatives: bronchoalveolar carcinoma, = carcinoids,=20 nodules < 1 cm=20
Can provide information for staging =

Invasive Diagnostic Methods =

Bronchoscopy=20

Very poor yield with lesions < 1.5 = cm=20
40%=9660% yield with lesions 2.5=963 cm =
Enhanced yield with lesions close to = bronchus=20

Transthoracic Fine-Needle Aspiration=20 Biopsy=20

> 90% sensitivity for malignant lesions = > 2=20 cm=20
Significant false negative rate with smaller, = centrally=20 located lesions

Surgery=20

Video-assisted thoracic surgery for = established or=20 suspected malignancy in patients at low surgical risk=20

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Best=20 Therapy

Most benign lesions require no therapy=20
Malignant lesions treated on basis of = diagnosis=20
Primary lung cancer in good surgical = candidates treated=20 with lobectomy

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Best References=20

Detterbeck FC, et al: Chest 125:2294, = 2004

Libby DM, et al: Chest 125:1522, 2004

Ost D, et al: N Engl J Med 348:2535, = 2003

Ost D, Fein A: Curr Opin Pulm Med 10:272,=20 2004

Gerald W. Staton, Jr., M.D., = F.A.C.P.,=20 has received grants for educational activities from GlaxoSmithKline and=20 Boehringer Ingelheim GmbH and serves as an advisor to=20 GlaxoSmithKline

January=20 2006