[Pseudotumor in the parotid region].

Tophaceous pseudogout is a rare form of calcium pyrophosphate dihydrate (CPPD) crystal deposition disease. Half of the 31 reported cases of tophaceous pseudogout are in the head and neck region. This patient presented with a parotid tumour, that was initially suspected to be malignant based on radiology and cytology. Operation disclosed a tumour progressing to the base of the skull, histological examination showed inflammatory cells, macrophages, metaplastic chondroid cells and giant cells of foreign-body-type. X-ray diffraction revealed two crystal forms of CPPD.