World disparities in risk definition and management of retinoblastoma: A report from the International Retinoblastoma Staging Working Group

Abstract

Following from the publication of the International Retinoblastoma Staging System, an open internet discussion group was created at the www.cure4kids.org resource. The results of a survey distributed among participants are discussed. Although most patients with retinoblastoma were treated under prospective protocols, there was a wide variation in the definition of risk criteria and in the criteria for giving adjuvant chemotherapy following enucleation. Definition of high-risk histological features and the criteria for use of adjuvant therapy will be standardized in future studies. Internet meetings are a valuable mechanism for enabling participation from under-resourced countries in the development of cooperative studies.

Strategies to manage retinoblastoma in developing countries

“…Isolated choroidal invasion is the typical example where a higher risk of extraocular relapse has been reported and adjuvant therapy has been recommended by some authors while others propose withholding adjuvant therapy [49]. According to the results of studies conducted in MICs, the relapse rate is near 3% [45]; therefore, the role of adjuvant chemotherapy would be difficult to estimate, even with adequately designed prospective studies.…”

Postenucleation Adjuvant Chemotherapy With Vincristine, Etoposide, and Carboplatin for the Treatment of High-Risk Retinoblastoma

“…12,16,17 Following enucleation, the incidence of high-risk histopathologic features has varied from 7% to 9% for anterior segment invasion, 8,17 12% to 42% for choroidal invasion, 5,7-9,17 8% to 12% for scleral invasion, 5,8,9,17 2% to 20% for extrascleral invasion, 5,8,9,17 6% to 28% for invasion of postlaminar optic nerve, 5,6,8,9,17,18 1% to 38% for involvement of optic nerve to surgical transection. 5,6,7,8,9,17,18 In a recent comprehensive report on histopathologic findings following enucleation in 297 According to Chantada and associates, 12 there are world disparities in risk definition and management of RB. On the basis of our previous experience, we believe that anterior segment invasion, massive posterior uveal invasion of 3 mm or greater, postlaminar optic nerve invasion, or a combination of any degree of posterior uveal and optic nerve invasion pose a risk; therefore, we include these 4 factors in our definition as high-risk.…”

“…The other major source of variation is related to the definition of massive choroidal invasion. 12 In a survey by the International Retinoblastoma Staging…”

“…For consensus in that group, the criterion for massive choroidal invasion was agreed to be maximum diameter (thickness or width) of tumor at 3 mm or greater. 12 A search for the most effective chemotherapy for RB has been underway since the 1950s. [19][20][21][22] Previous studies on adjuvant chemotherapy for high-risk RB have revealed several protocols including agents such as vincristine sulfate, doxorubicin hydrochloride, cyclophosphamide, etoposide, cisplatin, carboplatin, and cyclosporine.…”

Retinoblastoma

“…There are wide variations in the definitions of the degree of invasion to the ocular coats among many centers, which further complicates the interpretation of results from different groups. The International Retinoblastoma Staging Working Group found a great disparity in the processing of eyes, definition of pathology criteria, and treatment, in a survey that included large centers in developing and developed countries (Chantada et al 2008). Therefore, a guideline for eye processing intended to be disseminated in developing countries, and providing consensus definitions for the different degrees of invasion to the ocular coats has been agreed upon and published (see chapter 3).…”