대한흉부영상의학회 Weekly Chest Cases

Case No : 636 Date 2010-01-03

Courtesy of Chang Hyun Lee / Seoul National University Hospital
Age/Sex 78 / M
Chief ComplaintIncidentally found lung nodule in routine health check-up.

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Diagnosis With Brief Discussion

Diagnosis: Hamartoma
Radiologic Findings: On chest CT scan, a well defined nodule is seen in the right upper lobe. A focal low attenuated portion is noted in the anterior part of the lesion. On PET-CT scan, the nodule does not show hypermetabolism.
Brief Review: A hamartoma may be defined as a developmental malformation composed of tissues that normally constitute in organ in which the tumor occurs, but in which the tissue elements, although mature, are disorganized. In the lung, the term traditionally refers to a well-defined tumor consisting predominantly of cartilage and adipose tissue. It can occur within the lung parenchyma or in an endobronchial location.
Radiologically, pulmonary hamartomas typically are well-defined, solitary nodules without lobar predilection. The majority are smaller than 4cm in diameter, although some occasionally grow to a very large size. Although some studies have reported an incidence of calcification as high as 25 to 30 percent, others have identified it far less often. When calcification is present, however, the roentgenographic pattern most often resembles popcorn, a finding that is almost diagnostic. The presence of fat and calcium make the CT diagnosis exquisitely accurate. In a report of 47 lesions studied by CT, 30 (63.8%) contained fat only (n=18), calcium and fat (n=10) or calcium alone (n=2). Thin sections must be used to identify fat with certainty. On thicker sections, a small cavity may be confused with fat because of partial volume averaging.
In the absence of the characteristic calcification or fat, the differential diagnosis includes all other solitary pulmonary nodules, particularly carcinoma.
References: 1. Fraser RS, Pare J.A.Peter, Fraser RG, Pare P.D. Synopsis of Diseases of the Chest. 2nd edition. W.B. Saunders Company. 1994: 518-522.
2. Naidich DP, Webb WR, Muller NL, Krinsky GA, Zerhouni EA, Siegelman SS. Computed Tomography and Magnetic Resonance of the Thorax. New York. Lippincott-Raven. 1999 : 321
Please refer to: Case 37 Case 146 Case 308 Case 429 Case 531
Keywords: Lung, Benign tumor,

No. of Applicants : 88

▶ Correct Answer : 10/88, 11.4%

- Osaka University , Japan Osamu Honda
- Seoul National University Hospital , Korea (South) JUNG KIM
- seoul national university hospital , Korea (South) Ijin Joo
- IRCCS Istituto Oncologico - Bari , Italy Carlo Florio
- care hospital , India Chary D
- EKH-Berlin , Germany Michael Weber
- Louisiana State University - Shreveport , United States Carlos Previgliano
- Kashan University of Medical Sciences, kashan , Iran Ebrahim Razi
- CH Sud Rnion , Reunion jean-baptiste Noel
- clinique de SAVOIE , France, Metropolitan gay-depassier philippe

▶ Correct Answer as Differential Diagnosis : 11/88, 12.5%

- University of British Columbia , Canada Amr Ajlan
- Hospital M�e de Deus , Brazil Thiago Bento da Silva
- Diskapi Yildirim Beyazit Hospital, Ankara , Turkey Meric Tuzun
- SAISEIKAI KURIHASHI HOSPITAL , Japan YASUO OKUBO
- Saga University , Japan Ryoko Egashira
- Vital Imaging Centre, Mumbai,India , India Ganesh Agrawal
- jaslok hospital & research centre mumbai , India JAINENDRA JAIN
- NTUH , Taiwan Kuei-pin Chung
- NASA SCANS , India RAKESH BHATIA
- Trakya University School of Medicine , Turkey Umut Ugur
- UZ GASTHUISBERG , Belgium Johan COOLEN

대한흉부영상의학회 Korean Society of Thoracic Radiology

Archive of Old Cases

Case No : 636 Date 2010-01-03

Discussion

No. of Applicants : 88