[Multidetector computed tomography assessment of the degree of differentiation of bronchial carcinoid tumors]

Tracheobronchial tumors

Tumors of trachea and bronchi are uncommon and can occur in the form of benign or low- and high-grade malignant tumors. Although tracheobronchial tumors (TBTs) represent only 0.6% of all pulmonary tumors, they are clinically significant. Delays in diagnosis of these tumors commonly occur because the signs and symptoms caused by these tumors are nonspecific and chest radiographs are often considered unremarkable. Therefore, novel radiological techniques and better access to flexible bronchoscopy enable detection of larger number of TBT. The purpose of this article is to provide a review of tracheal and bronchial tumors and discuss significant aspects of the different TBT with focus on clinical manifestations and diagnostic procedures.

Low-Grade and High-Grade Mucoepidermoid Carcinoma of the Lung: CT Findings and Clinical Features of 17 Cases

OBJECTIVE

The objective of our study was to characterize the CT features and clinical findings of low-grade and high-grade mucoepidermoid carcinoma (MEC) of the lung.

MATERIALS AND METHODS

The CT findings and clinical information of 17 consecutive patients with primary low-grade (n = 11) or high-grade (n = 6) MEC were analyzed retrospectively. We assessed tumor location, size, contour, margin, density, calcification, obstructive changes, presence of metastasis, and enhancement.

RESULTS

In patients with low-grade MEC, tumor location was central in 10 and peripheral in one. In contrast, one and five tumors in patients with high-grade MEC were central and peripheral, respectively. There was a significant difference between central and peripheral locations among tumor grades (p = 0.005). In low-grade MECs, tumor contour was smoothly oval (n = 3) or spheric (n = 4); four were lobular. In five patients with low-grade MEC, tumors had well-defined margins; margins in the other six were poorly defined. Tumor density was homogeneous and heterogeneous in eight and three low-grade tumors, respectively. All six high-grade tumors had heterogeneous density, lobular contours, and poorly defined margins. Enhancement in both low-grade and high-grade tumors was greater than that of chest wall muscles, and low-grade tumors showed greater enhancement (46.90 ± 20.44 HU) than did high-grade tumors (22.50 ± 8.38 HU) (p = 0.015).

CONCLUSION

A markedly enhanced homogeneous central bronchial nodule or mass may suggest low-grade MEC. High-grade MEC tends to be peripheral, to have poorly defined margins, and to be lobular, heterogeneous nodules or masses with less enhancement.