Abstract
Malignant transformation of an intradiploic epidermoid cyst into an invasive squamous cell carcinoma (SCC) is an exceptionally rare and highly aggressive clinical entity. We present the case of a 72-year-old male with a three-year history of worsening headaches. Neuroimaging revealed an extra-axial cystic lesion arising from the right occipital diploic space, associated with a distinct calvarial bone defect and significant mass effect on the posterior fossa structures. The patient successfully underwent surgical resection under a tailored neuroanesthetic regimen. Histopathological examination confirmed a primary intradiploic epidermoid cyst with malignant transformation to invasive SCC. This report highlights the clinical presentation, complex intraoperative neuroanesthetic and surgical challenges, radiological markers of malignancy, and critical pathological findings of this rare condition.
