JCO Research Round Up
March 4, 2013
New findings from a prospective clinical trial in children with non-hereditary retinoblastoma affecting only one eye (unilateral retinoblastoma) will help doctors identify patients who should not receive chemotherapy after surgical removal of the diseased eye.
Nearly all patients with unilateral retinoblastoma are cured by surgery. Unfortunately, some patients have an increased risk of the disease coming back or spreading. For each patient, the risk of relapse and metastasis is estimated based on evaluation of tumor tissue removed during surgery under a microscope. Tumors are categorized as low-, intermediate-, or high-risk.
Patients with high-risk disease all receive intensive postoperative chemotherapy and radiation. But for low- and intermediate-risk disease, there is no general consensus as to which patients should or shouldn’t receive postoperative chemotherapy.
In the study, 123 children with unilateral retinoblastoma were assigned to risk categories after undergoing eye removal surgery. Patients with low-risk disease (70 patients) received no postoperative chemotherapy, those with intermediate-risk disease (52 patients) received four courses of chemotherapy (etoposide, carboplatin, vincristine, cyclophosphamide), and the only patient with high-risk disease received six courses of intensive chemotherapy (etoposide, carboplatin, thiotepa, vincristine, and cyclophosphamide).
All children were alive after a median follow-up period of six years. None of the patients experienced disease worsening, relapse, distant metastasis or second cancers. The postoperative chemotherapy regimens were safe overall.
The researchers have recently launched another study to confirm these results as well to see if postoperative chemotherapy could be reduced to two cycles for certain patients with intermediate-risk disease.
What This Means for Patients
The findings of this study will help standardize postoperative treatment decisions for children with non-hereditary unilateral retinoblastoma. The chemotherapy regimens for intermediate- and high-risk disease administered in this study were safe and 100 percent effective in preventing disease recurrence and metastasis, suggesting that those regimens are very good options for such patients. It appears that for some patients with intermediate-risk disease, it may be safe to reduce the intensity of chemotherapy or even avoid it entirely, but more research is needed to confirm this possibility.
Patients with low-risk disease had excellent outcomes despite having received no postoperative treatment. The finding indicates that those patients should not receive chemotherapy after surgery and can be reassured that forgoing postoperative chemotherapy will not jeopardize their survival. Moreover, by avoiding chemotherapy, the children are spared of its immediate and late harmful effects.