Retinoblastoma diagnosis: first signs and pre-diagnostic intervals

Abstract

Introduction: retinoblastoma is the most common intraocular malignancy of childhood and its incidence is one case per 15,000 to 20,000 live births. The successful treatment of retinoblastoma depends mainly on early diagnosis. Parents are usually the first to notice early signs of the disease and report difficulty by health professionals to value the symptoms, experiencing a prolonged period until diagnosis. Objectives: to identify characteristics of pre-diagnostic trajectory of children with retinoblastoma enrolled in Instituto Nacional de Cancer (INCA) between January 2006 and September 2013, as well as socio-demographic, epidemiological and clinical data of these patients.
Methods: retrospective study of a series of cases, through a semi-structured questionnaire administered to parents or caregivers of retinoblastoma patients. Participants were asked after consultations in ocular oncology clinic or through invitation by telephone. Results: out of 85 patients studied, 43 (50.6%) were male. Fifty-nine (69.4%) patients had unilateral retinoblastoma and 26 (30.6%) were bilateral. Average age at enrollment was 1.9 (SD: 1.3) years. Parents were the first to notice the first signs in 60 (75%) cases. 
Leukocoria was the initial sign cited with 60 (70.6%) cases, followed by strabismus with 23 (27.1%) cases. At diagnosis, 67 (78.8%) cases were intraocular, 13 (15.3%) extraocular and 5 (5.9%) metastatic. Only 33 (38.8%) of caregivers alleged that the child had been submitted to Red Reflex Test for screening and only one examination was interpreted as abnormal. The Family interval (time between perception and first appointment with a doctor)
lasted an average of 1.8 (SD: 2.7)months, the Medical interval (time between first appoint ment and enrollment in INCA) 5.8 (SD: 6.5) months and finally the Total Interval (Interval + Family Medical interval) lasted average of 7.6 (SD: 8.2) months. In the bivariate analysis, Medical and Interval Total interval showed a statistically significant correlation with advanced stage at diagnosis and death. The lack of leukocoria as a first sign had also a statistically significant relation to prolonged Medical and Total Intervals. Parents educational level had
a statistically significant relation to initial stage and death. The children were evaluated by more than 4 doctors in 32% of cases and had their complaints underestimated in 48% of cases. Out of 111 affected eyes, 79 (71.2%) were enucleated and 32 (28.8%) were preserved. During follow-up of 36.2 ± 35.4 months, 15 (17.7%) patients died. Conclusion: through the analysis of the trajectory of the families to the arrival at the cancer treatment center, we see the existence of several barriers to early diagnosis. Low parental education, multiplicity of medical appointments and inadequate screening were
some of these findings. Medical Interval was accountable for 76% of Total Interval. It seems that an effective action of medical education about retinoblastoma could increase awareness and promote early diagnosis.