Intradiploic epidermoid cyst overlying the torcula: a surgical challenge

Intradiploic epidermoid cyst in the skull: Case report and systematic review

Intradiploic epidermoid cysts are rare, benign tumors, accounting for less than 1% of all intracranial tumors. Due to their scarcity, we are reporting a case of an intradiploic epidermoid cyst and reviewing several similar cases in the literature to provide a better description of this tumor and analyze its clinical and radiological features. We conducted a search on the PubMed database for studies published between January 2010 and February 2023, including studies of nontraumatic and noniatrogenic calvarial cysts. We found a total of 34 studies and 41 patients, with an average patient age of 42.5 years. Common symptoms included painless masses, headaches, and seizures. The occipital, frontal, and parietal regions were the most common locations for these tumors. Some patients experienced complications such as otitis media, infection, or extension into the orbit and brain. Surgical resection was performed in all cases except for 2 patients with contraindications to surgery. Histological examination confirmed the diagnosis of an intradiploic epidermoid cyst. These cysts are rare skull lesions and can potentially cause neurological deficits due to their mass effect. If incompletely resected, they may also undergo malignant transformation. No single institution has accumulated enough cases to describe this rare tumor accurately. Therefore, through this review, we aim to highlight this tumor's epidemiological, clinical, and radiological features.

Intradiploic epidermoid cysts - a series of three cases and our experience with literature data

Intracranial epidermoid cysts are rare, representing almost 1% of all primary tumors and when are located in the diploe result from entrapped ectodermal embryonic remnants. Because of frequent complications, imaging studies are mandatory for highlighting erosions of both outer and inner table of the calvaria and treatment preparation. We enlisted three female patients within our study, comparing imaging with histopathology aspects. Even though the bone destruction was evident, no atypia or malignant signs were highlighted in serial sections. The interesting fact that we present is that our patients are all females, opposed to what is written in literature. Although the positive diagnosis can be made by imaging, histopathological examination of these cysts is mandatory for identifying malignant behavior.

Atypical intracranial epidermoid cysts: rare anomalies with unique radiological features

Epidermoid cysts are benign slow growing extra-axial tumours that insinuate between brain structures, while their occurrences in intra-axial or intradiploic locations are exceptionally rare. We present the clinical, imaging, and pathological findings in two patients with atypical epidermoid cysts. CT and MRI findings for the first case revealed an intraparenchymal epidermoid cyst that demonstrated no restricted diffusion. The second case demonstrated an aggressive epidermoid cyst that invaded into the intradiploic spaces, transverse sinus, and the calvarium. The timing of ectodermal tissue sequestration during fetal development may account for the occurrence of atypical epidermoid cysts.