Epidermoid and dermoid tumors are benign cutaneous developmental anomalies. They arise from the embryonic development of the adenohypophysis from a stomodeal origin. They can develop inflammatory, metaplastic and neoplastic processes in the sellar and parasellar regions [1], [2], [3]. These tumors are rare and constitute 1%–2% of all intracranial tumors [4], [5].

Epidermoid cysts typically exhibit a pearly-appearing capsule lined through a thin layer of squamous epithelium and a keratohyalin granular layer. However, dermoid cysts contain adnexal structures, such as hair follicles and glandular elements, located anywhere in the skull [2], [3], [6]. Although dermoid tumors grow at the midline of the skull, epidermoid tumors usually occur at the cerebellopontine angle. However, both lesions may be in the sellar or parasellar regions. The parasellar area where the tumor capsule can become quite adherent to critical neurovascular structures, such as cranial nerves, arteries, and vital tissue such as the brainstem and can cause significant mass effect and morbidity [6], [7], [8].

Clinical symptoms are associated with the location of the tumor. These may include headache, fatigue, decreased visual acuity or visual field loss, diabetes insipidus (DI), menstrual failure and galactorrhea, usually in the third and fourth decades [3], [7], [9], [10]. They may present with an acute rupture that causes chemical meningitis, seizure, haemorrhage, neurological deficits or psychosis [3], [4], [5], [11].

The primary treatment for symptomatic sellar and parasellar epithelial cystic lesions is surgery, Microscopic transcranial or microscopic transnasal approach is common [7], [11], [12]. Endoscopic surgical treatment may be suitable for these ventral skull base tumors.

Epidermoid and dermoid cysts require the most complete resection to avoid recurrence. To achieve the best GTR for ventral skull base tumors from crista galli to clivus, skull base surgeons use the transnasal rather than transcranial approaches. However, these tumors are very rare and require considerable surgical expertise.

The aim of this study is to reveal the results of different resection rates and the factors affecting resection rates. We present a case series of patients who were operated in a fully endoscopic transnasal fashion and include a literature review highlighting outcomes of endoscopically operated epidermoid/dermoid tumors in the ventral aspect of skull base with different clinical experiences.