 But he made a crucial observation that certain cancers (carcinoma in the modern sense) were inherently associated with white blood cells (which are now called macrophages) that produced irritation (inflammation).It was only towards the end of the 20th century that Virchow's theory was taken seriously.It was realised that specific cancers (including those of mesothelioma, lung, prostate, bladder, pancreatic, cervical, esophageal, melanoma, and head and neck) are indeed strongly associated with long-term inflammation.