Trilateral retinoblastoma: potentially curable with intensive chemotherapy

Trilateral retinoblastoma has been lethal in virtually all cases previously reported. We describe a series of 13 patients treated with intensive chemotherapy, defined as the intention to include high-dose chemotherapy with autologous hematopoietic stem cell rescue.

Induction chemotherapy generally included vincristine, cisplatin or carboplatin, cyclophosphamide, and etoposide. Hematopoietic stem cells typically were harvested after the first or second cycle of induction chemotherapy, usually from peripheral blood. High-dose chemotherapy regimens were thiotepa-based (n = 7) or melphalan and cyclophosphamide (n = 3).

Trilateral sites were pineal (n = 11) and suprasellar (n = 2); 7 patients had localized (M-0) disease and six had leptomeningeal dissemination (M-1+). Five patients had trilateral retinoblastoma at original diagnosis of intra-ocular retinoblastoma; eight later developed trilateral disease at a median of 35 months (range 3-60 months) following diagnosis of intra-ocular retinoblastoma. One patient died of toxicity (septicemia and multi-organ system failure) during induction and three developed disease progression prior to high-dose chemotherapy. Nine patients received high-dose chemotherapy at a median of 5 months (range 4-9) post-diagnosis of trilateral disease. Five patients survive event-free at a median of 77 months (range 36-104 months) and never received external beam radiation therapy. Four of seven patients with M-0 disease survive event-free versus only one of six patients with M-1+ disease.

Intensive chemotherapy is potentially curative for some patients with trilateral retinoblastoma, especially those with M-0 disease.