Clinical Analysis of 16 Distant Metastatic Retinoblastoma Cases with Event-Free Survival

Abstract

Aim: This study aimed to summarize the clinical characteristics, treatment, and outcomes of distant metastatic retinoblastoma with event-free survival.

Design: Retrospective interventional case series.

Methods: We screened patients with retinoblastoma who survived without events after the comprehensive treatment of distant metastases from June 2015 to February 2021 and collected information regarding their basic characteristics, diagnosis, and treatment. All patients received systemic intravenous chemotherapy. Other treatments included surgical treatment, radiotherapy, intrathecal chemotherapy, and autologous stem cell transplantation.

Results: Among 780 hospitalized patients with retinoblastoma in the pediatric ward, a total of 94 patients with retinoblastoma were diagnosed with distant metastases, and 16 patients with distant metastatic retinoblastoma who survived more than 6 months without events were screened, including eight male and eight female patients. The median age of onset was 29 (range, 11-120) months. Among the 16 patients, central nervous system metastasis (8/16), bone metastasis (8/16), bone marrow infiltration (4/16), lymph node metastasis (4/16), and parotid gland metastasis (3/16) were presented. All patients received treatment for more than 6 months, completed their regimen by February 2021, and survived without events. The median survival time after the onset of retinoblastoma was 50.5 (range, 23-102) months, the median survival time after metastasis was 43.5 (range, 16-71) months, and the median event-free survival was 29.0 (range, 6-59) months.

Conclusion: Metastatic retinoblastoma may benefit from comprehensive treatments including systemic intravenous chemotherapy and hematopoietic stem cell transplantation. However, recurrence after treatment still needs attention, and patients in complete remission still need long-term follow-up.

Keywords: comprehensive treatment; distant metastasis; retinoblastoma.

Figure 1

RB case with metastasis to parotid gland. (A-1) T1WI+C FS Status after vitrectomy (misdiagnosed at onset) in the right eye. Irregular equal T1 signals can be seen around the eyeball, locally protruding outside the orbit, and the enhanced scan is slightly enhanced, involving the lacrimal sac area and extraocular muscles. (A-2) T1WI+C FS Abnormal signal in the right parotid area with swollen lymph nodes, and the enhanced scan showed uneven enhancement. (B-1) T1WI+C FS Postoperative state of the right eye, with mild and uneven enhancement of the orbital fat body; (B-2) T1WI+C FS The original parotid gland area and lymph node enlargement subsided.

Figure 2

Survival curve of the 16 patients with RB with metastasis. Kaplan-Meier survival curve of the 16 included patients, the median OS of RB was 50.5 (range, 23–102) months, the median EFS after metastasis was 43.5 (range, 16–71) months, the median EFS after treatment was 29 (range, 6–59) months.

Figure 3

RB case with metastasis. Among all 94 patients with metastatic RB, 65 patients died, including eight patients who died of tumor recurrence after CR; two patients were lost to follow-up; 27 patients survived (four patients were under treatment, and seven patients achieved CR but did not meet the above inclusion criteria). The overall survival rate of 94 patients with metastatic RB was 28.7%.