We present the case of a 19-year-old patient who was admitted with a subcutaneous scalp lump associated with bilateral papilloedema. CT demonstrated a large heterogeneous vault lesion destroying the right parietal bone. The mass was hyperdense and enhanced slightly with contrast. An important intracranial epidural extension was also demonstrated. The mass was completely removed through a parietal craniectomy and histological examination was characteristic for a B-cell non-Hodgkin's lymphoma. Staging revealed other bony lesions and neoplastic cells were also found in the CSF. Systemic and intrathecal chemotherapy were administered. This report discusses both the clinical differential diagnosis of scalp masses and the radiological diagnosis of skull lesions.