Establishment of patient-derived xenografts of retinoblastoma and choroidal melanoma on the avian chorioallantoic membrane

Purpose: To develop a viable in vivo chorioallantoic membrane (CAM) model to study the growth and invasion of patient?derived retinoblastoma (RB) and choroidal melanoma (CM) xenografts (PDXs). The study utilizes primary tumor samples instead of cancer cell lines, which provides a more authentic representation of tumors due to conserved morphology and heterogeneity. Methods: Fertilized chicken eggs were procured, windowed, and their CAM layers were dropped. On embryonic development day (EDD) 10, freshly cut patient?derived CM and RB tumors were implanted on the CAM layer and the setup was incubated for 7 days. The tumor?embedded CAM layer was harvested on EDD 17, and the extracted tumor samples were subjected to hematoxylin and eosin staining and immunohistochemical analysis to evaluate the extent of tumor invasion. Results: Significant changes in the vascularity around the RB and CM PDXs were observed, indicating an angiogenic environment. The cross?sectional histological view of the tumor implant site revealed the invasion of both the tumors into the CAM mesoderm. Invasion of CM into CAM mesoderm was visualized in the form of pigmented nodules, and that of RB was indicated by synaptophysin and Ki?67 positivity in Immunohistochemistry (IHC). Conclusion: The CAM xenograft model was successfully able to support the growth of CM and RB PDXs and their invasion in CAM, thus presenting as a feasible alternative to mammalian models for studying tumorigenicity and invasiveness of ocular tumors. Moreover, this model can further be utilized to develop personalized medicine by inoculating patient?specific tumors for preclinical drug screening.

Immunohistochemical and mutational status of telomerase reverse transcriptase in conjunctival squamous cell carcinoma

Purpose: Mutations in human telomerase reverse transcriptase (TERT) are associated with increased telomerase activity in cutaneous melanomas. Conjunctival squamous cell carcinoma, also referred to as ocular surface squamous cell carcinoma, is cancer on the surface of the eye. Recent studies have identified UV signature mutations in TERT promoters in ocular melanoma and ocular surface squamous neoplasia. However, its immunohistochemical status has not been reported in ocular surface squamous cell carcinoma. This study aimed to explore the immunohistochemical and mutational status of TERT in ocular surface SCC. Methods: The immunohistochemical expression of TERT and mutational status of TERT promoter was evaluated in 19 ocular surface squamous cell carcinoma cases. Conjunctival melanoma tissue was used as a positive control. Results: The cytoplasmic overexpression of TERT was detected in 11/19 (57%), and TERT promoter mutations were identified in 6/19 (31%) of ocular surface squamous cell carcinoma. Out of these, 66% had a C228T mutation, and 33% had a C250T mutation. The TERT expression was found to be associated with a high (?T3) AJCC category (P = 0.023), and TERT immunoexpression was significantly correlated with reduced disease?free survival (P = 0.024, log?rank analysis) in ocular surface squamous cell carcinoma patients. Conclusion: The present study demonstrates that TERT promoter mutations with UV signatures are frequent in ocular surface squamous cell carcinoma. The increased expression of TERT could be of biological significance in aggressive ocular surface squamous cell carcinoma.

Delayed onset of congenital hereditary endothelial dystrophy due to compound heterozygous SLC4A11 mutations.

Background: Congenital hereditary endothelial dystrophy (CHED) is an autosomal recessive disorder characterized by bilateral, symmetrical, noninflammatory corneal clouding (edema) present at birth or shortly thereafter. This study reports on an unusual delayed presentation of CHED with compound heterozygous SLC4A11 mutations. Materials and Methods: A 45‑year‑old female, presenting with bilateral decreased vision since childhood that deteriorated in the last 5 years, was evaluated to rule out trauma, viral illness, chemical injury, glaucoma, and corneal endothelial dystrophies. Tear sample was sent for herpes simplex viral (HSV) antigen testing. Genomic DNA from peripheral blood was screened for mutations in all exons of SLC4A11 by direct sequencing. Full‑thickness penetrating keratoplasty was done and corneal button was sent for histopathological examination. Results: Slit‑lamp findings revealed bilateral diffuse corneal edema and left eye spheroidal degeneration with scarring. Increased corneal thickness (762 μm and 854 μm in the right and left eyes, respectively), normal intraocular pressure (12 mmHg and 16 mmHg in the right and left eyes, respectively), inconclusive confocal scan, and specular microscopy, near normal tear film parameters, were the other clinical features. HSV‑polymerase chain reaction was negative. Histopathological examination revealed markedly thickened Descemet’s membrane with subepithelial spheroidal degeneration. SLC4A11 screening showed a novel variant p.Ser415Asn, reported mutation p.Cys386Arg and two polymorphisms, all in the heterozygous state and not identified in 100 controls. Conclusions: The study shows, for the first time, compound heterozygous SLC4A11 mutations impair protein function leading to delayed onset of the disease.

Primary liposarcoma of the orbit.

Liposarcoma is the most common sarcoma in adults, but is an extremely rare tumor of the orbit. We report 4 cases of primary orbital liposarcoma treated at our center. All cases had tumor localized to the orbit and underwent exenteration followed by radiotherapy in one patient. None of the patients had a recurrence until a follow-up of 1-5 years (mean: 4 years).

Immunohistochemical localization of human papilloma virus in conjunctival neoplasias: a retrospective study.

BACKGROUND: The extent of association of human papilloma virus (HPV) in human conjunctival neoplasias has been debated in studies originating from different parts of the world, but no substantial evidence has been generated on Indian subjects. This prompted us to carry out a retrospective study on conjunctival neoplasias diagnosed over the past 12 years. MATERIALS AND METHODS: Histopathological and immunohistochemical analysis of 65 specimens of ocular neoplasias and 30 normal controls diagnosed between 1991 and 2002 at a tertiary eye care hospital, was undertaken. Formalin-fixed, paraffin-embedded tissues were reviewed for confirming histopathological diagnosis, presence of koilocytosis and changes related to actinic keratosis. Immunohistochemical analysis was done using HPV-specific monoclonal antibodies. Clinicopathological correlation and the association of HPV antigen with the histopathological features were performed. RESULTS: Out of the 65 cases analyzed, 35 were papillomas and 30 were ocular surface squamous neoplasias (OSSN). The mean age was 48 years with a male preponderance. Histologically, koilocytosis was observed in 17.1% of papillomas and 36.6% of OSSN. Actinic keratosis was present in 33% of OSSN. Immunohistochemically 17.1% conjunctival papillomas stained positive for HPV antigen, all cases of OSSN were negative for HPV. There was no correlation between koilocytosis or actinic keratosis and the detection of HPV antigen. CONCLUSIONS: The association between HPV and conjunctival neoplasias is variable in different geographical areas and also depends on the methods of detection used. This study warrants the need for applying more advanced techniques at a molecular level to determine the possible etiology of HPV in conjunctival neoplasias among Asian-Indians.

Bilateral dissociated vertical deviation in a case of congenital hereditary endothelial dystrophy.

Dissociated vertical deviation (DVD) is an intermittent anomaly of the non-fixing eye. Although association of DVD with sensory visual deprivation owing to congenital or acquired opacities of the ocular media has been reported, its association with congenital hereditary endothelial dystrophy (CHED) has not been reported hitherto. We report a case having a bilateral asymmetric DVD, in a know case of bilateral CHED.

Conjunctival rhinosporidiosis.

Conjunctival rhinosporidiosis is usually a surprise diagnosis in histological section of an excised conjunctival mass. The condition is rarely encountered outside the endemic coastal areas of South India. Accurate diagnosis of this rare condition is infrequent in clinical practice; tumour, neoplasm, papilloma being the common misdiagnoses. Herein, a report of a case of an 18-year-old otherwise healthy male who attended outpatient department of Regional Institute of Ophthalmology, Medical College, Kolkata with a red fleshy papillomatous growth about 7 mm x 4 mm in size, in the palpebral conjunctiva just behind the intermarginal strip of his right upper lid. His routine blood examination was within normal limits. The growth was excised under local anaesthesia and histopathological examination revealed rhinosporidiosis. There was no recurrence of the growth within one month of follow-up.