A Multicenter, International Collaborative Study for AJCC-Staging of Retinoblastoma: Metastasis-Associated Mortality

Purpose: To evaluate the ability of the 8th edition of the American Joint Committee on Cancer (AJCC) Cancer Staging Manual to estimate metastatic and mortality rates for children with retinoblastoma (RB). Design: International, multicenter, registry-based retrospective case series. Participants: A total of 2190 patients from 18 ophthalmic oncology centers from 13 countries over 6 continents. Methods: Patient-specific data fields for RB were designed and selected by subcommittee. All patients with RB with adequate records to allow tumor staging by the AJCC criteria and follow-up for metastatic disease were studied. Main Outcome Measures: Metastasis-related 5- and 10-year survival data after initial tumor staging were estimated with the KaplaneMeier method depending on AJCC clinical (cTNM) and pathological (pTNM) tumor, node, metastasis category and age, tumor laterality, and presence of heritable trait. Results: Of 2190 patients, the records of 2085 patients (95.2%) with 2905 eyes were complete. The median age at diagnosis was 17.0 months. A total of 1260 patients (65.4%) had unilateral RB. Among the 2085 patients, tumor categories were cT1a in 55 (2.6%), cT1b in 168 (8.1%), cT2a in 197 (9.4%), cT2b in 812 (38.9%), cT3 in 835 (40.0%), and cT4 in 18 (0.9%). Of these, 1397 eyes in 1353 patients (48.1%) were treated with enucleation. A total of 109 patients (5.2%) developed metastases and died. The median time (n ¼ 92) from diagnosis to metastasis was 9.50 months. The 5-year KaplaneMeier cumulative survival estimates by clinical tumor categories were 100% for category cT1a, 98% (95% confidence interval [CI], 97e99) for cT1b and cT2a, 96% (95% CI, 95e97) for cT2b, 89% (95% CI, 88e90) for cT3 tumors, and 45% (95% CI, 31e59) for cT4 tumors. Risk of metastasis increased with increasing cT (and pT) category (P < 0.001). Cox proportional hazards regression analysis confirmed a higher risk of metastasis in category cT3 (hazard rate [HR], 8.09; 95% CI, 2.55e25.70; P < 0.001) and cT4 (HR, 48.55; 95% CI, 12.86e183.27; P < 0.001) compared with category cT1. Age, tumor laterality, and presence of heritable traits did not influence the incidence of metastatic disease. Conclusions: Multicenter, international, internet-based data sharing facilitated analysis of the 8th edition AJCC RB Staging System for metastasis-related mortality and offered a proof of concept yielding quantitative, predictive estimates per category in a large, real-life, heterogeneous patient population with RB.Fil: Tomar, Ankit Singh. The New York Eye Cancer Center; Estados UnidosFil: Finger, Paul T.. The New York Eye Cancer Center; Estados UnidosFil: Gallie, Brenda. The Eye Cancer Clinic, Princess Margaret Cancer Centre; CanadáFil: Mallipatna, Ashwin. Hospital for Sick Children; CanadáFil: Kivelä, Tero T.. Helsinki University Hospital; FinlandiaFil: Zhang, Chengyue. Beijing Children's Hospital; ChinaFil: Zhao, Junyang. Beijing Children's Hospital; ChinaFil: Wilson, Matthew W.. University of Tennessee; Estados UnidosFil: Kim, Jonathan. University of Southern California; Estados UnidosFil: Khetan, Vikas. Sankara Nethralaya; IndiaFil: Ganesan, Suganeswari. Sankara Nethralaya; IndiaFil: Yarovoy, Andrey. Fyodorov Eye Microsurgery Federal State Institution; RusiaFil: Yarovaya, Vera. Fyodorov Eye Microsurgery Federal State Institution; RusiaFil: Kotova, Elena. Fyodorov Eye Microsurgery Federal State Institution; RusiaFil: Yousef, Yacoub A.. King Hussein Cancer Center; JordaniaFil: Nummi, Kalle. University of Helsinki; FinlandiaFil: Ushakova, Tatiana L.. Blokhin National Medical Research Center Oncology of Russian Federation; RusiaFil: Yugay, Olga V.. Blokhin National Medical Research Center Oncology of Russian Federation; RusiaFil: Polyakov, Vladimir G.. Blokhin National Medical Research Center Oncology of Russian Federation; RusiaFil: Ramirez Ortiz, Marco A.. Hospital Infantil de México Federico Gómez; MéxicoFil: Esparza Aguiar, Elizabeth. Hospital Infantil de México Federico Gómez; MéxicoFil: Chantada, Guillermo Luis. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Schaiquevich, Paula Susana. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Fandino, Adriana. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; ArgentinaFil: Yam, Jason C.. The Chinese University of Hong Kong; Hong KongFil: Lau, Winnie W.. The Chinese University of Hong Kong; Hong KongFil: Lam, Carol P.. The Chinese University of Hong Kong; Hong KongFil: Sharwood, Phillipa. University of Sydney; AustraliaFil: Moorthy, Sonia. KK Women's and Children's Hospital; SingapurFil: Long, Quah Boon. KK Women's and Children's Hospital; Singapu