On the missing link between inflammation and cancer.

A various array of cutaneous granulomatous disorders have been found to be associated with internal malignancy. Among them, sarcoidosis, granuloma anulare (GA), psoriasis, pyoderma gangrenosum (PG), or other neutrophilic dermatoses such as the Sweet syndrome and subcorneal pustular dermatosis may precede the development of a neoplastic process by months or years. Pathogenic links of inflammation with cancer are discussed, including inflammation, intrinsic immune dysfunction, cytokines and interleukins, angiogenetic factors, and epigenetic changes.