Pediatric ocular and periocular tumors

A Review of Pediatric Ophthalmic Tumors

Tumors of the eye, orbit, and ocular adnexa can arise in the pediatric population. These entities can be both vision- and life-threatening and may be associated with systemic disease. Given their relative rarity, pediatricians must be aware of these conditions and understand what findings warrant immediate referral to an ophthalmologist for initiation of further testing. We aimed to review these conditions and highlight clinical features to promote awareness and expedite diagnosis. Tumors are subdivided into the following categories for review: anterior tumors of the eyelid and ocular surface, orbital tumors, and intraocular tumors.

Exosomes: Insights from Retinoblastoma and Other Eye Cancers

Exosomes, considered as cell debris or garbage bags, have been later characterized as nanometer-sized extracellular double-membrane lipid bilayer bio-vesicles secreted by the fusion of vesicular bodies with the plasma membrane. The constituents and the rate of exosomes formation differ in different pathophysiological conditions. Exosomes are also observed and studied in different parts of the eye, like the retina, cornea, aqueous, and vitreous humor. Tear fluid consists of exosomes that are shown to regulate various cellular processes. The role of exosomes in eye cancers, especially retinoblastoma (RB), is not well explored, although few studies point towards their presence. Retinoblastoma is an intraocular tumor that constitutes 3% of cases of cancer in children. Diagnosis of RB may require invasive procedures, which might lead to the spread of the disease to other parts. Due to this reason, better ways of diagnosis are being explored. Studies on the exosomes in RB tumors and serum might help designing better diagnostic approaches for RB. In this article, we reviewed studies on exosomes in the eye, with a special emphasis on RB. We also reviewed miRNAs expressed in RB tumor, serum, and cell lines and analyzed the targets of these miRNAs from the proteins identified in the RB tumor exosomes. hsa-miR-494 and hsa-miR-9, upregulated and downregulated, respectively in RB, have the maximum number of targets. Although oppositely regulated, they share the same targets in the proteins identified in RB tumor exosomes. Overall this review provides the up-to-date progress in the area of eye exosome research, with an emphasis on RB.

Tumors of the conjunctiva and cornea

Tumors of the conjunctiva and cornea comprise a large and varied spectrum of conditions. These tumors are grouped into two major categories of congenital and acquired lesions. The acquired lesions are further subdivided based on origin of the mass into surface epithelial, melanocytic, vascular, fibrous, neural, histiocytic, myxoid, myogenic, lipomatous, lymphoid, leukemic, metastatic and secondary tumors. Melanocytic lesions include nevus, racial melanosis, primary acquired melanosis, melanoma, and other ocular surface conditions like ocular melanocytosis and secondary pigmentary deposition. The most frequent nonmelanocytic neoplastic lesions include squamous cell carcinoma and lymphoma, both of which have typical features appreciated on clinical examination. The caruncle displays a slightly different array of tumors compared to those elsewhere on the conjunctiva, as nevus and papilloma are most common, but oncocytoma and sebaceous gland hyperplasia, adenoma, and carcinoma can be found. In this report, we provide clinical description and illustration of the many conjunctival and corneal tumors and we discuss tumor management.

Tumors of the conjunctiva and cornea

Tumors of the conjunctiva and cornea comprise a large and varied spectrum of conditions. These tumors are grouped into two major categories of congenital and acquired lesions. The acquired lesions are further subdivided based on origin of the mass into surface epithelial, melanocytic, vascular, fibrous, neural, histiocytic, myxoid, myogenic, lipomatous, lymphoid, leukemic, metastatic and secondary tumors. Melanocytic lesions include nevus, racial melanosis, primary acquired melanosis, melanoma, and other ocular surface conditions like ocular melanocytosis and secondary pigmentary deposition. The most frequent nonmelanocytic neoplastic lesions include squamous cell carcinoma and lymphoma, both of which have typical features appreciated on clinical examination. The caruncle displays a slightly different array of tumors compared to those elsewhere on the conjunctiva, as nevus and papilloma are most common, but oncocytoma and sebaceous gland hyperplasia, adenoma, and carcinoma can be found. In this report, we provide clinical description and illustration of the many conjunctival and corneal tumors and we discuss tumor management.