ABSTRACT
Biopsy of a mass lesion implies tissue sampling for histopathologic examination. Tissue sampling can be done with different methodologies. Biopsy techniques include excisional, incisional, core, aspiration biopsies as well as intraoperative biopsy with frozen section and Mohs methods. Sentinel node biopsy is also utilized occasionally for staging purposes of certain tumors. Most of the anteriorly located and well-delineated tumors can be excised. Incisional biopsy material provides sufficient amount of tissue for pathological examination which is usually obtained from mid or posterior orbital lesions. It is easier to reach the mid and posterior orbit with core or fine-needle aspiration biopsy techniques, but these methods provide a limited amount of tissue material. Incisional techniques should preferably be performed on any atypical lesion. Incisional biopsy may promote tumor seeding and lead to local scarring for conjunctiva malignant melanoma. Excisional biopsy is always preferred. If the area of suspected tumor or the area of pigmentation is extensive, map biopsies are made. Sebaceous adenocarcinoma spreads diffusely by pagetoid invasion throughout the conjunctiva. Map biopsy of the conjunctiva to determine the extent of involvement of sebaceous adenocarcinoma should be done. Vitreous and chorioretinal biopsy are very useful for differential diagnosis of posterior segment atypical lesions.