Eman D Albalawi1, Hind M Alkatan2, Sahar M Elkhamary3, Leen Abu Safieh4, Azza M Y Maktabi5. 1. Anterior Segment Division, King Khalid Eye Specialist Hospital, Riyadh, Saudi Arabia. 2. Departments of Ophthalmology and Pathology, King Saud University, Riyadh, Saudi Arabia. Electronic address: hindkatan@yahoo.com. 3. Radiology Department, King Khalid Eye Specialist Hospital, Riyadh, Saudi Arabia; Department of Diagnostic Radiology, Mansoura Faculty of Medicine, Mansoura, Egypt. 4. Research Department, King Khalid Eye Specialist Hospital, Riyadh, Saudi Arabia. 5. Pathology and Laboratory Medicine Department, King Khalid Eye Specialist Hospital, Riyadh, Saudi Arabia.
Abstract
OBJECTIVE: Orbital Rhabdomyosarcoma is a highly malignant tumor predominantly affecting children. Our study adds more understanding of this tumor to ophthalmologists from the clinicopathological, radiological and genetic aspects. DESIGN: A retrospective clinicopathological and radiological study of ocular rhabdomyosarcoma with genetic profiling. PARTICIPANTS: All the cases with confirmed tissue diagnosis of orbital rhabdomyosarcoma presenting at a tertiary eye hospital in Riyadh, Saudi Arabia during the period 1985-2015. METHODS: Charts and histological slides of 26 patients were reviewed. DNA was extracted from paraffin-embedded biopsies and genotyping was performed to detect chromosomal abnormalities and Copy-number variations regions. RESULTS: 18 males and 8 females were included with a mean age at presentation of 6.9 years (SD of 4.4). Proptosis and globe displacement were the commonest clinical presentations. Embryonal histopathological type was the commonest (73.1%) with superior orbital involvement (p = 0.024). Using magnetic resonance imaging, the embryonal type showed higher Apparent diffusion coefficient (ADC) value compared to the alveolar type (p = 0.98). Genetic profiling showed Copy-number gain in regions spanning PAX3, DDIT3, Gli, Wnt6 genes. DICER1 gene implication was found in 9 sporadic cases. CONCLUSION: Rhabdomyosarcoma is rare and occurs with a mean age of 7 years, predominantly among males. The commonest embryonal type is significantly correlated with superior orbital involvement. Radiologically, it shows an ADC of 0.67-0.09 × 10-3mm2/s. (p = 0.98). The gain in PAX3, DDIT3, Gli1, Wnt6 genes is a new finding while the DICER1 gene implication in the absence of familial hereditary carcinoma is another interesting finding.
OBJECTIVE:Orbital Rhabdomyosarcoma is a highly malignant tumor predominantly affecting children. Our study adds more understanding of this tumor to ophthalmologists from the clinicopathological, radiological and genetic aspects. DESIGN: A retrospective clinicopathological and radiological study of ocular rhabdomyosarcoma with genetic profiling. PARTICIPANTS: All the cases with confirmed tissue diagnosis of orbital rhabdomyosarcoma presenting at a tertiary eye hospital in Riyadh, Saudi Arabia during the period 1985-2015. METHODS: Charts and histological slides of 26 patients were reviewed. DNA was extracted from paraffin-embedded biopsies and genotyping was performed to detect chromosomal abnormalities and Copy-number variations regions. RESULTS: 18 males and 8 females were included with a mean age at presentation of 6.9 years (SD of 4.4). Proptosis and globe displacement were the commonest clinical presentations. Embryonal histopathological type was the commonest (73.1%) with superior orbital involvement (p = 0.024). Using magnetic resonance imaging, the embryonal type showed higher Apparent diffusion coefficient (ADC) value compared to the alveolar type (p = 0.98). Genetic profiling showed Copy-number gain in regions spanning PAX3, DDIT3, Gli, Wnt6 genes. DICER1 gene implication was found in 9 sporadic cases. CONCLUSION:Rhabdomyosarcoma is rare and occurs with a mean age of 7 years, predominantly among males. The commonest embryonal type is significantly correlated with superior orbital involvement. Radiologically, it shows an ADC of 0.67-0.09 × 10-3mm2/s. (p = 0.98). The gain in PAX3, DDIT3, Gli1, Wnt6 genes is a new finding while the DICER1 gene implication in the absence of familial hereditary carcinoma is another interesting finding.