Lymphangitic carcinomatosis (LC) refers to the diffuse infiltration and obstruction of pulmonary parenchymal lymphatic channels by tumour. Various neoplasms can cause lymphangitic carcinomatosis, but 80% are adenocarcinomas. The most common primary sites are the breasts, lungs, colon, and stomach. (Ali Nawaz Khan, Lymphangitic Carcinomatosis Imaging) The plain film appearance of lymphangitis carcinomatosis (LC) is highly characteristic and therefore readily recognised. It can be useful for radiographers to be aware of the plain film pattern of LC given that there may be other more subtle signs of metastatic disease worthy of supplementary imaging.

• Lymphangitic carcinomatosis is believed to initially occur as hematogenous spread of tumor to the lungs

• The tumor then invades the vessels wall and into the lymphatics
• Tumor spreads through the lymphatics which provide little resistance to spread
• Alternatively, there may be central obstruction of mediastinal or hilar lymph nodes leading to direct infiltration

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	64 year old lady with known lung Ca. There is a nodular pattern throughout both lungfields consistent with lymphangitis carcinomatosis. There is loss of visualisation of the left T10 pedicle and partial loss of visualisation of the right pedicle at the same level. This is likely to be associated with metastatic disease. There is a left pleural effusion Spinal hardware noted
	There is loss of visualisation of the left T10 pedicle (arrowed)