대한흉부영상의학회 Korean Society of Thoracic Radiology

Discussion

Diagnosis With Brief Discussion

Diagnosis

Typical Carcinoid

Radiologic Findings

Chest radiograph shows well-marginated, round, solitary pulmonary nodule of 2.5 cm in diameter in right upper lobe. Thin-section CT scan with IV contrast (100 cc, 2 cc/sec) shows moderate contrast enhancement (20-25 HU) of the nodule with focal area of central low attenuation. No calcification is seen.
Pathologic examination on the tumor obtained with right upper lobectomy confirmed typical carcinoid.
In this particular case, contrast enhancement was not that remarkable.

Brief Review

1. Carcinoid tumor is a low-grade malignant tumor, only about 0.5 % to 2.5 % of all pulmonary neoplasm. Typical carcinoid represents 80 % to 90 % of carcinoid tumors.

2. A part of neuroendocrine carcinoma of the lung (typical carcinoid - atypical carcinoid - small cell carcinoma - large cell neuroendocrine carcinoma, non-small cell carcinoma with neuroendocrine feature)

3. Slightly female preponderance, at the age of late 30s to late 40s.

4. Good prognosis with infrequent lymph node spread and rare distant metastasis.

5. Radiologic findings depend on the location of the tumor.

1) Central tumor (up to 80 % of carcinoid tumors): atelectasis or postobstructive pneumonitis.
Endobronchial component is readily seen with CT scan.

2) Peripheral tumor: solitary pulmonary nodule less than 3 cm in diameter in most cases,
often calcified (approximately 30% of the tumor with CT and pathologic studies).

CT with IV contrast shows strong enhancement due to vascular nature of the tumor.

References

1. Foster BB, Muller NL, Miller RR, Nelems B, Evans KG. Neuroendocrine carcinomas of the lung: clinical, radiologic, and pathologic correlation. Radiology 1989; 170:441-445
2. Fraser RS, Muller NL, Colman N, Pare PD. Diagnosis of diseases of the chest. 4th ed. Saunders: Philadelphia, 1999; 1229-1243

Keywords

Lung, Malignant tumor,