The incidence and distribution of retinoblastoma in Kenya

Abstract

To determine the incidence and distribution of retinoblastoma in Kenya we performed a retrospective study of patients seen from 1st January 2006 to 31st December 2007. Of 206 suspected cases of retinoblastoma identified, 58 (28.2%) referred cases were not found at any treatment center and 148 (71.8%) were successfully traced to facilities where they were treated, of which 16 cases were excluded (3 missing files and 13 cases ruled out on histology). The remaining 132 confirmed cases comprised of 79 (59.8%) males and 53 (40.2%) females (p=0.016), 34 (25.8%) bilateral and 98 (74.2%) unilateral cases. The overall mean age at presentation was 33.5 months (SD 20.8); the difference between the mean age of the bilateral cases (25.4 months, SD 16.8) and unilateral cases (36.3 months, SD 20.8) was statistically significant (p=0.008). Only 6 (4.5%) confirmed cases reported a positive family history. The calculated incidence for 2007 was 1 in 17,030 live births. In the first study of its kind in Kenya, we show the incidence of retinoblastoma is similar to that reported globally, with no ethnic or regional variation in its distribution. Similar to other resource-poor settings, children with retinoblastoma in Kenya presented late, even those with positive family history. Many cases were lost after referral. We recommend that in addition to increasing public awareness, better documentation in a retinoblastoma register is likely to improve patient follow-up after referral, leading to timely treatment of affected children