Histopathologic risk factors for metastasis in retinoblastoma seen in a tertiary eye center in South, South Nigeria

Abstract

Roseline Ekanem Duke, Hardeep Mudhar, Enembe Okokon

Purpose: To analyze the frequency of histopathological high-risk factors (HRF) for systemic metastasis in retinoblastoma (RB) in our patient population. Materials and Methods: This is a retrospective case series, with review of clinical data and histopathologic, immunocytochemistry slides, from a particular laboratory, of eyes enucleated for RB between 2006 and 2012. Results: A total of 28 eyes with histopathologic reports confirming RB from a particular laboratory were seen between 2006 and 2012. The mean age at presentation was 33.68 ± 12.27 months (range: 6-55 months). 15 (53.60%) of the patients were males, and 13 (46.40%) were females. Approximately 12 (43%) of these patients presented with leucocoria, while the least frequent presentation was strabismus 2 (7%). The mean duration of symptoms at presentation was 7.07 ± 4.29 months. Grade E intraocular classification for RB was seen in 27 (96.40%) of cases. International staging classification of stages included Stage 1 (1 patient, 3.57%), Stage 2 (2, 7.14%), Stage 3A (4, 14.30%), Stage 3B: (6, 21.40%) Stage 4A (2, 7.14%) and Stage 4B (13, 46%). HRF that were predictive of metastasis were choroidal infiltration (20 patients, 71.40%), retrolaminar optic nerve (ON) invasion (17, 60.70%), invasion of the ON to transection 1 (6, 78.60%), scleral infiltration (23, 82.10%) and extra-scleral extension (13, 46.40%). Conclusion: There is a high frequency of histopathological risk factors present in the patients with eyes enucleated for RB in this population. This finding is in agreement with suggestions of poor prognosis and high-mortality in this region, especially from the central nervous system metastasis.