October 18, 2023
A tumour deposit is a group of cancer cells that have spread from the primary tumour (the location where the tumour started) to another tissue or organ in the body. A tumour deposit can be found close to the primary tumour, or in other organs and body sites far from the original tumour. When a deposit is found far from the primary tumour it is called a metastasis.
Tumour deposits are commonly found in lymph nodes, lungs, bones, and the liver. Tumour deposits can also be found in the same organ as the primary tumour. In this situation, the deposit is distinct and clearly separated from the primary tumour.
Tumour deposits are important because your pathologist will use this information to determine the pathologic cancer stage (pTNM). Specifically, tumour deposits found in lymph nodes close to the primary tumour are often used to determine the pathologic nodal stage (pN). Tumour deposits found in lymph nodes further from the original tumour, or in another organ (lung, liver, or bone), are used to determine the pathologic metastatic stage (pM) of cancer.
This article was written by doctors to help you read and understand your pathology report. Contact us if you have questions about this article or your pathology report.