Updated project metadata. We performed a quantitative proteome comparison on formalin-fixed paraffin embedded (FFPE) tissue of metastasized and non-metastasized primary prostate cancer (PCa) and on recurrent lymph node metastases. Comparing these three sample groups, we aimed to identify proteins, that might potentially promote/supress tumor progression or metastasis formation. Proteins were quantified label-free. Proteins with interesting biological functions were followed-up by immunohistochemistry.