Scanning electron microscopy of retinoblastoma

Area of Science:

• Ophthalmology
• Pathology
• Cell Biology

Background:

• Retinoblastoma is a malignant tumor of the retina.
• Undifferentiated retinoblastoma presents diagnostic challenges due to atypical morphology.
• Typical rosettes are a characteristic feature of some retinoblastoma subtypes.

Purpose of the Study:

• To describe two cases of undifferentiated retinoblastoma lacking typical rosettes.
• To investigate the ultrastructural features of these atypical retinoblastoma cells.
• To identify any associated cellular or tissue elements.

Main Methods:

• Case study analysis of two patients diagnosed with retinoblastoma.
• Histopathological examination of tumor samples.
• Scanning electron microscopy (SEM) for ultrastructural analysis.

Main Results:

• Absence of classic Flexner-Wintersteiner or Homer Wright rosettes.
• Presence of cell groups with rosette-like formations.
• SEM revealed cells arranged in circular or garland-like patterns.
• One case showed associated lymphocytes; the other had photoreceptor elements and endothelial tubuloreticular inclusions.

Conclusions:

• Undifferentiated retinoblastoma can exhibit rosette-like structures without forming typical rosettes.
• SEM is valuable for identifying subtle cellular arrangements in challenging retinoblastoma cases.
• Associated findings like lymphocytes or photoreceptor elements may offer prognostic or diagnostic clues.