Clinical and magnetic resonance imaging features of 14 patients with trilateral retinoblastoma.

Background: Our study aimed to comprehensively investigate the age of onset, magnetic resonance imaging (MRI) features, and prognosis of children with trilateral retinoblastoma (TRB).

Methods: We included 14 patients with TRB diagnosed or followed up in our hospital. The age of onset and MRI features of the intraocular tumor and intracranial lesions were evaluated. A follow-up study was also conducted.

Results: A total of 11 participants were diagnosed with concurrent TRB at the age of 11.1±7.4 months, and 3 participants had late-onset TRB at age 37±19.1 months. The incidence of TRB with unilateral eye involvement was 7.1% (1/14). The intraocular tumors showed intense enhancement in contrast-enhanced T1-weighted images (WI) and significant diffusion restriction in diffusion WI (DWI) with an apparent diffusion coefficient (ADC) of (0.619±0.22)×10 mm/s. The intracranial lesions showed similar DWI aspects with an ADC value of (0.680±0.206)×10 mm/s. Therapeutically, 8 participants had a period of intraocular tumor stabilization and significant intracranial lesion volume reduction after chemotherapy, and 6 participants had given up treatment. Only 2 participants who simultaneously received high-dose chemotherapy and autologous hematopoietic stem cell rescue were still alive with no recurrence at 24 and 54 months of follow-up. The 1-, 2-, and 3-year overall survival (OS) rates were 80%, 18.75%, and 12.5%, respectively.

Conclusions: Patients with unilateral or bilateral RB can develop TRB. The intraocular and intracranial tumors showed slightly different ADC values. High-dose chemotherapy, combined with stem cell rescue can significantly improve survival. A long term and scheduled follow-up before 60 months of age is necessary for screening later-onset TRB patients.