대한흉부영상의학회 Korean Society of Thoracic Radiology

Discussion

Diagnosis With Brief Discussion

Courtesy

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Imaging Findings

Chest radiographs shows atelectasis of the right middle and lower lobes.

Precontrast CT scan shows a well-defined mass in the right middle and lower lobes. The mass contains several calcifications at the peripheral portion.

The mass is homogenously enhanced. But several low-densities are seen at the central area on early and late phases on contrast-enhanced CT scan.

Past History

A 47-year old woman presented with cough, fever, and blood-tinged sputum for 4 days.
No history of tuberculosis and no previous operation.

Discussion

Bronchial carcinoids constitute less than 5 % of pulmonary tumors. The age range is wide, stretching from teenagers to old age (mean age: 55 years).

They show a spectrum of microscopic appearances and clinical behavior ranging from slow-growing locally invasive tumor with a moderately fast growth rate.

There are two well-described forms of bronchial carcinoid: typical carcinoid and atypical carcinoid.

Atypical carcinoid has cellular and clinical features intermediate between those of typical carcinoid and small cell carcinoma. All three of these tumors are neuroendocrine origin, being derived from bronchial and bronchiolar amino precursor uptake decarboxylation (APUD) cells. The tumor has been called Kulchisky cell carcinoma.


Only 15% of typical carcinoids metastasize, and half of typical carcinoids metastasized. The great majority of typical carcinoids arise in the main, lobar (75 %) and segmental bronchi and may cause cough. Repeated pneumonia, bronchiectasis, and lung abscess may occur.

Bronchial carcinoids are vascular tumors and may present with hemoptysis. Centrally located bronchial carcinoids may be predominantly intraluminal, may grow along the lumen of the bronchus, or may predominantly extraluminal, in which case they are known as "iceberg" lesion.


Bronchial carcinoids are visible on plain film as a hilar mass in about 25 %. The appearance differs from carcinoma in that the bronchus may widen slightly as it approaches the mass. Approximately 10 -20% of bronchial carcinoids appear as a well-defined SPN. Calcification or ossification is occasionally recognized.


CT scanning provides superb anatomic localization, but usually carcinoid cannot be distinguished from carcinoma unless the lesion is demonstrably ossified. The incidence of calcification detectable by CT appears to be considerable: 4 of 12 cases in one series.

The incidence of calcification is slightly greater in centrally located tumors and in the larger tumors. Patterns of calcification are seen including multiple nodular and curvilinear configurations. Sometimes the calcification takes the form of recognizable ossification.

Contrast enhancement, which is sometimes marked, is seen in most cases of bronchial carcinoid.


On bronchoscopy, the mass protruded into the intermediate bronchus.

Bilobectomy of right middle and lower lobes was performed.

Pathologic specimen shows protruding, well-demarcated, endobronchial mass within the right lower lobe bronchus. Sections from the tumor show a circumscribed mass with organoid nesting pattern, trabecular pattern of monotonous cells containing granular chromatin, eosinophilic and granular cytoplasm. There are areas of vascular invasion and tumor nests within fibrous capsule and just beneath the bronchial mucosa. The tumor cells are positive for chromogranin and synaptophysin.

Reference

1. Armstrong P, Wilson AG, Dee P, Hansell DM. Imaging of diseases of the chest. 2nd ed. 304-310.
2. Zwiebel BR, Austin JHM, Grimes MM. Bronchial carcinoid tumors: assessment with CT of location and intratumoral calcification in 31 patients. Radiology 1991; 179:483-486.

Keywords

Airway, Malignant tumor,