Objectives: The aim of this case report is to do a short revision of PCNs and emphasize the importance of an adequate knowledge of the patient's medical history, physical examination and a detailed analysis of imaging studies.

Methods: A 47 year-old patient with history of multiple myeloma, who during physical examination show an important mass lesion in his left parietal zone near the middle line, hemiplegia in the right side, pyramidal signs, and lower consciousness level. CT scan showed a hyperdense image of 44.8 × 72.7 mm. Under general anesthesia a radical tumor resection was performed, and the sample was sent for histopathological studies.

Results: After radical excision of the lesion by surgery, the sample was sent for the respective histopathological study. This study refers calvaria tumor compatible with plasmacytoma, and also refers as a metastases of multiple myeloma with lytic bone destruction. Immunohistochemically was CD45LCA - Positive immunoreactivity in lymphocytes, Plasma cells - positive immunoreactivity in plasma cells, CD56 - positive immunoreactivity in plasma cells. Later, once known the results of histopathological studies the patient underwent radio-, and chemotherapy treatment.

Conclusions: PCNs can appear in almost every tissue of the body, including the skull, and it should be diagnosed and treated in time to improve prognosis of the patient.