Brief report: conservative treatment in unilateral retinoblastoma: a preliminary report

Outcomes of a two-drug chemotherapy regimen for intraocular retinoblastoma

BACKGROUND

Retinoblastoma is the most common intraocular tumor of childhood. Vision salvage rates in advanced cases are less than ideal, and the optimal treatment for intraocular retinoblastoma has not been established. We report the results of an institutional retinoblastoma treatment trial to determine the vision salvage rates and toxicity of a regimen combining carboplatin and etoposide with focal retinal therapy.

PROCEDURE

Twenty-nine patients diagnosed with retinoblastoma in 48 eyes were treated between 1992 and 2004 with at least six cycles of carboplatin and etoposide combined with focal retinal therapy.

RESULTS

The response rate of eyes after six cycles of chemotherapy was 85.4%. Twenty-two eyes were enucleated, but only seven eyes received EBRT. The vision salvage rate without EBRT was 82.6% for eyes with Reese-Ellsworth (R-E) groups I-IV tumors and 20% for eyes with R-E group V tumors. The vision salvage rate without EBRT for eyes with Murphree groups A and B tumors was 77.3% but was only 26.9% for eyes with groups C and D tumors. Acute side effects were minimal.

CONCLUSIONS

The combination of carboplatin and etoposide with focal therapy is a well-tolerated regimen that has acceptable vision salvage rates for R-E groups I-IV and Murphree groups A and B retinoblastoma. This combination avoids the use of EBRT and the toxicity of additional chemotherapy agents. However, patients with R-E group V and Murphree groups C and D retinoblastoma have poorer outcomes and require more intensive therapy.

[Survival and clinical features of retinoblastoma]

INTRODUCTION

Retinoblastoma (RB) is the most frequent intraocular tumor in the pediatric age group, representing 3 % of all childhood neoplasms. In Mexico, the annual incidence varies according to the geographical area studied, ranging from 4-24 cases/million in patients younger than 15 years. Ninety-five percent of cases occur in infants and pre-school children.

PATIENTS AND METHOD

An observational, retrospective, descriptive, cross-sectional study of all children with RB admitted to the Oncology Department of the Pediatric Hospital of the National Medical Center in a 10-year period was performed.

RESULTS

Fifty-six patients were included. The median age was 24 months. Forty-two children presented unilateral RB. Symptoms at diagnosis were leukokoria, strabismus and reduced visual sharpness. Distribution according to Prats' classification was the following: stage I, 5 patients; stage II, 32; stage III, 14; stage IV, 5. Histological analysis revealed 24 patients with poorly differentiated RB, 16 with well-differentiated RB, 13 with moderately differentiated RB and 7 with undifferentiated RB. In eight patients histological type was not identified. In 12 of the 56 patients cytogenetic and molecular studies were performed. All patients underwent surgery. Patients in the early stages were treated with chemotherapy. A total of 26.7 % of the group presented relapse. The disease-free survival at 10 years was 87.5 %.

CONCLUSIONS

As with other childhood neoplasms, early diagnosis and multidisciplinary management of RB has improved prognosis and survival. The symptoms, treatment and survival reported in this pediatric cohort are similar to those of other published series.