Rib Destruction

smoker, the possibility of lung cancer must be consi- dered. The patient should be referred to a lung cancer multidisciplinary team and a CT scan with intrave- nous contrast performed.

These are images from the thoracic CT examination of the same patient (Figs. 2.4.2and 2.4.3).

The CT images on bone windows confi rm the suspicion of a left apical mass (Figs. 2.4.2 and

2.4.3, long arrows). This has spiculate margins,

is not calcifi ed, and shows no evidence of cavi- tation. As on the chest radiograph, there is an expansile destructive rib lesion seen on the right

Examination Tips

This is a classic examination case that involves observation of the traditional “review areas.” The following points are important:

The practice of looking at the review areas and stating that “I am looking at the bones,” followed rapidly by the statement “… and they are normal” is all too common! A review of the all the bones shown on a chest X-ray takes some time and a cursory glance is to be avoided.

Look for the obvious causes of rib metastases that might be shown on a chest X-ray (i.e., lung cancer [as in the case shown], breast cancer [is there evi- dence of a mastectomy and/or surgical clips in the axilla?], or renal tumour [are surgical clips seen at the “edge” of the fi lm?]).

Diff erential Diagnosis

Metastatic disease (e.g., lung or breast) Plasmacytoma

Tuberculosis

Rare fungal infections

Brown tumour of hyperparathyroidism

Notes

Metastatic disease is the most common cause of malignant involvement of the ribs.

Metastases may be either lytic or sclerotic. Primary lung tumours may directly invade the

chest wall and destroy the adjacent ribs.

True primary neoplasms of the ribs are rare; chondroid lesions are the most common primary tumours and nearly always arise at or near the anterior end of the rib.

Enchondromas cause focal expansion of the rib.

Bibliography

Fig. 2.4.2

52

2 Chest Imaging

2.5 Aspergilloma

Clinical History

A 53-year-old man presents with a chronic cough

(Fig. 2.5.1).

Ideal Summary

This is an erect chest radiograph of an adult patient. There is homogeneous opacifi cation at the left upper zone associated with apical pleural thicke- ning. More importantly, at the left apex, there appears to be a cavity containing solid material

(Fig. 2.5.1, long arrow). Around this there is a cre-

scent of air lucency. No underlying rib abnormality is demonstrated. There are signs of volume loss as judged by the elevation of the left hilum and ipsi- lateral tracheal deviation. There is also possibly a thin-walled fi brocavity at the right apex with no obvious lateral pleural thickening (Fig. 2.5.1, short

arrow). Multiple small calcifi ed opacities that are likely to represent benign tuberculous granulomas are seen in the right lung. The fi ndings at the left apex are those of a mycetoma in a patient who is likely to have had tuberculosis in the past. I would further investigate this case with CT examination.

Fig. 2.5.1

RZ Sidhu_9783131662910_2013_Section 2.indd 52

2.5 Aspergilloma

These are the thoracic CT images of the same patient

(Figs. 2.5.2and 2.5.3).

The CT images support the suspicion on chest radio- graphs of fungal colonisation of the left apical fi b- rocavity (Figs. 2.5.2 and 2.5.3, long arrows), but additionally confi rm the presence of another (nonco- lonised) cavity on the right. There is marked pleural

Examination Tips

When shown a chest X-ray with upper zone volume loss or fi brosis, look for and comment on:

The presence or absence of intracavitary material. The presence or absence of air crescents.

Thickening of the lateral pleura (particularly if shown serial chest X-rays—this may be the fi rst sign that a mycetoma is forming in a pre-existing fi brocavity). This is a reactive phenomenon and may regress as the aspergilloma resolves.

Look for and describe, where possible, the signs of an underlying cause of a “fi brocavity” in the upper zones (i.e., previous tuberculosis, sarcoidosis). Look for and attempt to exclude lung cancer as a

possible cause (e.g., comment on rib destruction).

Diff erential Diagnosis

Mycetoma (most commonly related to Aspergillus

fumigatus infection)

Lung cancer

Notes

Fungal colonisation (also termed a “mycetoma” and most commonly caused by Aspergillus

fumigatus) often occurs as a consequence of any

fi brocavitary lung disease. The most common underlying causes of such fi brosis are tuberculosis and sarcoidosis.

There is a characteristic appearance on chest X-ray and CT with intracavitary material— typically in the upper zones—surrounded by a crescent of air density (the “air crescent” sign).

Bibliography

Buckingham SJ, Hansell DM. Aspergillus in the lung: diverse and coincident forms. Eur Radiol 2003;13(8):1786–1800 Franquet T, Müller NL, Giménez A, Guembe P, de La Torre J,

Bagué S. Spectrum of pulmonary aspergillosis: histologic, clinical, and radiologic fi ndings. Radiographics 2001;

Fig. 2.5.2

54

2 Chest Imaging

2.6 Carcinoid Tumour

Clinical History

A young man, who is otherwise well, presents with a cough (Fig. 2.6.1).

Ideal Summary

This is a chest radiograph of a young man. The lungs are clear, and the heart size is normal. The hila are also normal. Looking at the review areas confi rms that the apices are normal. There are no abnormalities below the hemidiaphragms. The ribs, visible spine, and remaining bones are normal. Behind the heart and, specifi cally, in the left main bronchus, there is a well-defi ned smooth mass (Fig. 2.6.1, arrow). The mass is of soft tissue density,

and there is no associated calcifi cation. There is no evidence of distal atelectasis or consolidation. There are no pleural eff usions.

The features indicate an endobronchial lesion. Possible causes include lung cancer, endobronchial metastases, and a carcinoid/neuroendocrine tumour. The patient should be referred to the lung cancer multidisciplinary team. Thoracic CT with intrave- nous contrast should also be requested.

Fig. 2.6.1

Fig. 2.6.2

These are images from the thoracic CT examination of the same patient (Figs. 2.6.2–2.6.4)

On these axial CT images on mediastinal and lung windows, there is evidence of a well-defi ned mass of soft tissue density protruding into the posterior aspect of the left main bronchus (Fig. 2.6.2, arrow). There is a defi nite extraluminal component. The mass is noncalcifi ed. The lungs are clear, and there are no complicating features such as distal atelectasis or

RZ Sidhu_9783131662910_2013_Section 2.indd 54