Abstract
Purpose :
Retinoblastoma (RB) is the most common intraocular cancer that affects 1 in ~20,000 lives soon after birth. Patients with the hereditary form of this childhood malignancy present bilaterally and are at lifelong risk of developing a second cancer. Radiation therapy used to treat RB further exacerbates the incidence of secondary cancers. The aim of this study is to evaluate the spectrum and nature of secondary cancers in long-term RB survivors.
Methods :
The study included all consecutive patients with a history of RB treated for a secondary cancer at MD Anderson between 1994 and 2018. Clinical data such as histological types of secondary cancer, treatments, bilateral status, and survival outcomes were analyzed. The associations among radiation or chemotherapy exposure as treatment for RB, unilateral vs. bilateral status, and types of secondary cancer were examined.
Results :
62 eligible patients (30 males and 32 females) were identified. The mean age at diagnosis of secondary cancer was 34.6 years (range 0 - 80, median 36). A wide spectrum of secondary cancer types were identified, including sarcoma, breast cancer, various skin cancers, GI/GU cancers, and endocrine cancers. Of all patients who had secondary cancers, 40 patients (64.5%) had bilateral RB and 17 patients (27.4%) had unilateral RB. We found that 35 patients (56.5%) who developed secondary cancers received radiation therapy during childhood as part of treatment of RB, and 17 patients (27.4%) received chemotherapy for treatment of RB. There was no significant association between radiation or chemotherapy as treatment for RB and the development of specific types of secondary cancers. The 5-year survival for RB patients diagnosed with a secondary cancer was 53.6% and the 10-year survival was 36.0%. The median age of onset of secondary cancer amongst RB survivors was during the 4th decade of life and at a median of 36.6 years after the original diagnosis of RB.
Conclusions :
In contrast to previous studies, we saw a broader variety of secondary cancer types in our cohort. Our findings deepen the understanding of secondary cancers in long-term RB survivors and help set guidelines for cancer screening and surveillance algorithms for RB survivors. All RB survivors, regardless of unilateral or status, should undergo strict cancer surveillance particularly after the 4th decade of life.
This is a 2020 ARVO Annual Meeting abstract.