Tissue biopsy is necessary for the management of patients with ocular cancers and benign growths. It is used to determine the diagnosis, assess tumor biology, and plan treatment strategies. The goals of a biopsy are to safely obtain a sample of tissue by minimizing cosmetic and functional risk. However, tumor location and presumptive clinical diagnosis affect both approach and technique (see Chapter 6). The pathologist’s preference is to receive an ample amount of tissue, enabling a comprehensive assessment of tumor cytology, tissue architecture, and invasion into neighboring normal tissues. A larger tissue sample allows for immunopathology, electron micrography, and/or molecular/genetic studies (as needed).
However, the current trend in ocular tumor tissue biopsy techniques shows a preference for smaller incisions and less invasive surgical procedures. For instance, in numerous non-ocular surgical scenarios, the adoption of smaller incisions has resulted in reduced complications and faster recovery rates.1 This evolution has been aided by the development of small endoscopic cameras, monitors, and micro-instrumentation. Likewise, ophthalmic pathologists face the challenge of diagnosing from increasingly smaller tissue samples and cells. Herein, we explore relatively recent and less invasive methods, such as exfoliative techniques, fine-needle aspiration biopsy (FNAB), aspiration-cutter techniques (Finger’s iridectomy technique [FIT], Finger’s aspiration cutter technique [FACT]), and liquid biopsy approaches.
The process of biopsy, whether involving large, small, or microincisions, begins with the patient’s history and clinical examination. When a patient’s medical history indicates multiorgan metastatic disease, confirmation may only necessitate a small tissue sample or cell specimen. Similarly, in cases of ocular surface squamous neoplasia, an exfoliative biopsy can distinguish between normal and dysplastic cells, enabling precise topical chemotherapy. The prebiopsy examination plays a crucial role in determining the appropriate handling and transport medium, as well as the specific studies to be conducted. We highly recommend that the eye cancer specialist consult with the ophthalmic pathologist to discuss the presumed diagnosis before proceeding with the biopsy surgery.
Incisional, excisional, shave, and punch biopsies com¬monly used for eyelid and adnexal tumors are described in Chapter 6. However, in the case of eyelid tumors, the minimally invasive biopsy techniques (MIBT) discussed in this chapter have played a relatively minor role. Conversely, MIBT has found extensive use in biopsies of the cornea, conjunctiva, anterior chamber, iris, ciliary body, vitreous, retina, choroid, and orbit. These innovative techniques allow for cytologic analysis of individual cells, small clumps, or microscopic masses, along with histopathology, immunopathology, DNA, and molecular analysis.