Frontal Chest X-Ray of an elderly male patient. X-Ray shows a large opacity, an area of increased density, indicating a collapse of the right upper lobe due to a hilar mass or tumour. ‘The hilar is a complex anatomical structure that appears as a wedge-shaped depression on the mediastinal surface of each lung where the bronchus, blood vessels, nerves and lymphatics enter or leave the lung’.(1) There is hyperlucency of the right lower and middle lobes, hyperlucency on chest x-ray is when one side of the chest appears more lucent (black) than the other. Also evident is elevation of the right hemidiaphragm which could be due to volume loss or possibly phrenic nerve paralysis. Although not a good example of the ‘Golden S sign’ Image 1 has elements of this radiological feature with the collapse of the right upper lobe and a hilar mass. Findings: (following CT and biopsy) Small Cell lung Cancer
Small-Cell Lung Carcinoma
Small-cell lung cancer is so named after the appearance of the cells; they are undifferentiated and smaller than normal cells consisting mainly of the nucleus with hardly any cytoplasm, for this reason small-cell lung cancer is also sometimes called ‘oat cell carcinoma’. Small-cell carcinomas are thought to originate from neuroendocrine cells that can be found in the bronchial mucosa. According to studies around 90 – 95% of small-cell lung cancers are centrally located and usually arise in a main bronchus or a lobar bronchi (a subdivision of the bronchus) and appear as hilar or perihilar growths. The remaining 5 – 10% of small-cell lung cancers present in a peripheral position of the lung.(2) Small-cell lung cancers tend to be aggressive, so even though the cells are small the tumours grow rapidly and are more widely metastatic (have a greater tendency to spread to other parts of the body) than non-small cell lung cancers.(3) The most common sites of metastatic spread in lung cancer include the other lung, the adrenal gland or glands, bone, brain and liver.
Frontal Chest X-Ray of a 35 year old female patient. This x-ray demonstrates a complicated right upper lobe atelectasis. An atelectasis is a partial collapse or incomplete inflation of the lung. In this case the atelectasis is caused by a large hilar mass in the central area of the right lung with clear formation of Golden’s Reverse S sign. The sign is seen in the right lung when there is a convex bulge in the median aspect of the horizontal fissure and the lateral aspect of the horizontal fissure is concave.(4) Also present is a large opacity in the right upper thorax and signs of volume loss. Findings: Large central hilar mass.
Small-cell lung cancers account for around 15 – 20% of all lung cancers(5) and are more strongly associated with cigarette smoking (occurring almost exclusively in smokers) than non-small-cell lung carcinoma, however 80 – 90% of all lung cancer cases are due to exposure, often over a long period to tobacco smoke.(6)
2. Titulaer MJ, Verschuuren JJ (2008). “Lambert-Eaton myasthenic syndrome: tumor versus nontumor forms”. Ann. N. Y. Acad. Sci. 1132: 129–34.
3. Collins J, Stern EJ. Chest radiology, the essentials. Lippincott Williams & Wilkins. (2007) ISBN:0781763142.
4. Gupta P (December 2004). “The Golden S sign”. Radiology 233 (3): 790–1. doi:10.1148/radiol.2333021407. PMID 15564409.
5. Shields TW, LoCicero J, Ponn RB. General thoracic surgery. Lippincott Williams & Wilkins. (2005) ISBN:078173889X.
6. Merck Manual Professional Edition ‘Lung Carcinoma: Tumors of the Lungs’. , Online edition. Retrieved 15 August 2007.