Macular retinoblastoma managed with chemoreduction: analysis of tumor control with or without adjuvant thermotherapy in 68 tumors.

OBJECTIVE To evaluate the effectiveness of chemoreduction alone and chemoreduction with thermotherapy for macular retinoblastoma. DESIGN Prospective, nonrandomized, single-center case series. SETTING Ocular Oncology Service at Wills Eye Hospital of Thomas Jefferson University in conjunction with the Division of Oncology at the Children's Hospital of Philadelphia (Pa). PARTICIPANTS There were 68 macular retinoblastomas in 62 eyes of 49 patients managed with chemoreduction from January 1995 through January 2003. Intervention All patients received 6 cycles of intravenous chemoreduction using vincristine, etoposide, and carboplatin. The patients were then treated according to 1 of 2 approaches: chemoreduction alone with no adjuvant focal therapy (group A) or chemoreduction combined with adjuvant foveal-sparing thermotherapy to each macular retinoblastoma (group B). Main Outcome Measure Tumor recurrence. RESULTS Of the 68 tumors, 28 were in group A and 40 were in group B. A comparison of both groups revealed that the tumors were similar with regard to clinical features. The mean tumor basal dimension was 12.3 mm for group A and 12.1 mm for group B, and the mean tumor thickness was 6.8 mm for group A and 6.1 mm for group B. Tumors in group A occupied a mean of 71% of the macula, and those in group B occupied 74% of the macula. Following treatment, Kaplan-Meier estimates revealed that group A tumors showed recurrence in 25% by 1 year and 35% by 4 years whereas those in group B showed recurrence in 17% by 1 year and 17% by 4 years. All recurrences were treated with additional focal thermotherapy, cryotherapy, or plaque radiotherapy except for 1 that required external beam radiotherapy and 1 that required enucleation, both in group A. Univariate analysis revealed that predictors of tumor recurrence were intraretinal growth pattern (vs endophytic); small tumor basal dimension (less than 3 mm and occupying a smaller percentage of the macula); absence of subretinal fluid, subretinal seeds, and vitreous seeds; and chemoreduction response with less tumor calcification and tumor regression of type 0 (complete disappearance without a scar). By multivariate analysis, the most important factors predictive of tumor recurrence were smaller macular tumor size (judged by percentage of the macula occupied by the tumor), absence of subretinal or vitreous seeds, and unilateral disease. CONCLUSIONS Treatment of macular retinoblastoma with chemoreduction plus adjuvant foveal-sparing thermotherapy provides tumor control of 83% by 4 years, and this is slightly more favorable than chemoreduction alone, which provides control of 65% by 4 years. Tumors most destined for recurrence are small tumors.