You will be presented with a citation segment from the section of a research paper. Classify the intent behind this citation by choosing from one of the following categories:

- Method: Cites the paper for its methodology or procedure.
- Background: Cites the paper to provide background information.
- Result: Cites the paper for its findings or results.

Your answer should be a single word from the following list of options: ["Method", "Background", "Result"]. Do not include any other text in your response.

Citation sentence:

Its clinical importance has been established for breast cancer since it is an independent prognostic factor highly associated with the incidence of metastasis.(2) Since they are very rapidly forming micro-vessels, porosity is high and when injecting IV contrast media, they spread the interstitial liquid of tumor mass they enhance.
Background