Objective: To evaluate the effectiveness of chemoreduction alone and chemoredu ction with thermotherapy for macular retinoblastoma. Design: Prospective, nonran domized, single-center case series. Setting: Ocular Oncology Service at Wills E ye Hospital of Thomas Jefferson University in conjunction with the Division of O ncology at the Children’s Hospital of Philadelphia (Pa). Participants: There we re 68 macular retinoblastomas in 62 eyes of 49 patients managed with chemoreduct ion from January 1995 through January 2003. Intervention: All patients received 6 cycles of intravenous chemoreduction using vincristine, etoposide, and carbopl atin. The patients were then treated according to 1 of 2 approaches: chemoreduct ion alone with no adjuvant focal therapy (group A) or chemoreduction combined wi th 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 t umors were similar with regard to clinical features. The mean tumor basal dimens ion was 12.3 mm for group A and 12.1 mm for group B, and the mean tumor thicknes s was 6.8 mm for group A and 6.1 mm for group B. Tumors in group A occupied a me an of 71%of the macula, and those in group B occupied 74%of the macula. Follow ing treatment, Kaplan-Meier estimates revealed that group A tumors showed recur rence in 25%by 1 year and 35%by 4 years whereas those in group B showed recurr ence in 17%by 1 year and 17%by 4 years. All recurrences were treated with addi tional focal thermotherapy, cryotherapy, or plaque radiotherapy except for 1 tha t required external beam radiotherapy and 1 that required enucleation, both in g roup A. Univariate analysis revealed that predictors of tumor recurrence were in traretinal growth pattern (vs endophytic); small tumor basal dimension (less tha n 3 mm and occupying a smaller percentage of the macula); absence of subretinal fluid, subretinal seeds, and vitreous seeds; and chemoreduction response with le ss tumor calcification and tumor regression of type 0 (complete disappearance wi thout a scar). By multivariate analysis, the most important factors predictive o f tumor recurrence were smallermacular tumor size (judged by percentage of thema cula occupied by the tumor), absence of subretinal or vitreous seeds, and unilat eral disease. Conclusions: Treatment of macular retino- blastomawith chemoreduction plus adjuvant foveal-sparing thermotherapy provid es tumor control of 83%by 4 years, and this is slightly more favorable than che moreduction alone, which provides control of 65%by 4 years. Tumors most destine d for recurrence are small tumors. Objective: To evaluate the effectiveness of chemoreduction alone and chemoreduction with thermotherapy for macular retinoblastoma. Design: Prospective, nonran domized, single-center case series. Setting: Ocular Oncology Service at Wills E ye Hospital of Thomas Jefferson University in conjunction with the Division of O ncology at the Children’s Hospital of Philadelphia (Pa). Participants: There we re 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 carbopl at in. The patients were then treated according to 1 of 2 approaches: chemoreduct ion alone with no adjuvant focal therapy (group A) or chemoreduction combined wi th 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 c omparison of both groups revealed that the umors were similar with regard to clinical features. The mean tumor basal dimens ion was 12.3 mm for group A and 12.1 mm for group B, and the mean tumor thicknesses was 6.8 mm for group A and 6.1 mm for group B. Tumors in group A occupied a me an of 71% of the macula, and those in group B occupied 74% of the macula. Follow ing treatment, Kaplan-Meier estimates that that group of Aumors showed recurrence in 25 % by 1 year and 35% by 4 years among those in group B showed recurrences in 17% by 1 year and 17% by 4 years. All recurrences were treated with addi tional focal thermotherapy, cryotherapy, or pla radiotherapy except for 1 tha t required external beam radiotherapy and 1 that required enucleation, both in g roup A. Univariate analysis revealed that predictors of tumor recurrence were in traretinal growth pattern (vs endophytic); small tumor basal dimension (less tha n 3 mm and occupying a smaller percentage of the macula); absence of suBy multivariate analysis, the most important factors predictive of tumor recurrence were smallermacular tumor size ( judged by percentage of the ma cula occupied by the tumor), absence of subretinal or vitreous seeds, and unilat eral disease. Conclusions: Treatment of macular retino- blastoma with chemoreduction plus adjuvant foveal-sparing thermotherapy provid es tumor control of 83% by 4 years, and this is slightly more favorable than che moreduction alone, which provides control 65% by 4 years. Tumors most destine d for recurrence are small tumors.