Unusual lung tumours: an illustrated review of CT features suggestive of this diagnosis

Abstract

This review presents an imaging-centred approach to the diagnostic challenge of uncommon lung tumours in adults. Emphasis is placed on features that may be used to differentiate these tumours including fat content, tumour site, multifocality, calcification and predominant pattern of involvement.

Tracheobronchial tumors

“…ACC ACC is the most common salivary-type tumor of large airways and the second common primary tracheal tumor with a prevalence of 0.04-0.2% (19). It should be considered as differential diagnosis, especially in younger adults with tumors in trachea and/or large bronchi (40)(41)(42). Most studies reported female predominance and no association with smoking (43).…”

“…However, nodules without these findings may be difficult for distinguishing from malignancies with CT alone. Postobstructive pneumonia or atelectasis can be present (Figure 8) (13,40,57). Hamartoma typically shows little or no radiotracer uptake on FDG PET.…”

“…The size of the lesions reported in the literature varies from less than 1 cm to more than 7 cm (2,62,63). The CT findings of a homogeneous mass with fatty density and no tumor contrast enhancement are considered diagnostic (40,64). Magnetic resonance imaging enables accurate determination of the morphological characteristics of the mass with a hypersignal on the T1-weighted images and an intermediate signal on the T2-weighted images, compatible with normal fat.…”

“…Mucous gland adenoma is one of the rarest epithelial neoplasms which comprises of less than 0.5% of all lung tumors with same essential histological features and prognosis like salivary glands tumors of the neck (20,40). MGAs arise from mucosal seromucous glands and ducts of trachea or bronchi (38,53,65).…”

Dynamic Computed Tomography Findings of Atypical Pulmonary Hamartoma and It's Pathologic Correlations: A Case Report

“…Pulmonary hamartoma is the third most frequent cause of solitary pulmonary nodules with an overall prevalence of up to 5.7% (1), and chondromatous hamartoma is the most common type of pulmonary hamartoma (2). Masses are composed of abnormal mixtures of epithelial and mesenchymal elements, such as cartilage, fat, fibromyxoid tissue, smooth muscle, and bone (3,4).…”