The authors presented two rare cases of scalp malignant nodular hidradenoma (MNH).[1] Both tumors recurred in spite of total excision and radiotherapy. The preferred treatment is an early wide surgical excision of the tumor. Recently, innovation of radiation delivery technique enabled IMRT (intensity modulated radiation therapy) for complex-shaped targets.[2] VMAT (volumetric modulated arc therapy) or Rapid Arc[3] therapy and helical tomotherapy[4] give a high dose to widely spread scalp and skull tumors, sparing the underlying brain parenchyma as much as possible. IMRT as well as chemotherapy including the molecular targeting therapy is to be evaluated for adjuvant therapy after the surgical resection or for salvage therapy in case of recurrence.