Efficacy and safety of bortezomib in patients with renal impairment: results from the APEX phase 3 study.

Renal impairment is associated with poor prognosis in multiple myeloma (MM). This subgroup analysis of the phase 3 Assessment of Proteasome Inhibition for Extending Remissions (APEX) study of bortezomib vs high-dose dexamethasone assessed efficacy and safety in patients with relapsed MM with varying degrees of renal impairment (creatinine clearance (CrCl) <30, 30-50, 51-80 and >80 ml min(-1)). Time to progression (TTP), overall survival (OS) and safety were compared between subgroups with CrCl < or =50 ml min(-1) (severe-to-moderate) and >50 ml min(-1) (no/mild impairment). Response rates with bortezomib were similar (36-47%) and time to response rapid (0.7-1.6 months) across subgroups. Although the trend was toward shorter TTP/OS in bortezomib patients with severe-to-moderate vs no/mild impairment, differences were not significant. OS was significantly shorter in dexamethasone patients with CrCl < or =50 vs >50 ml min(-1) (P=0.003), indicating that bortezomib is more effective than dexamethasone in overcoming the detrimental effect of renal impairment. Safety profile of bortezomib was comparable between subgroups. With dexamethasone, grade 3/4 adverse events (AEs), serious AEs and discontinuations for AEs were significantly elevated in patients with CrCl < or =50 vs >50 ml min(-1). These results indicate that bortezomib is active and well tolerated in patients with relapsed MM with varying degrees of renal insufficiency. Efficacy/safety were not substantially affected by severe-to-moderate vs no/mild impairment.

A phase 2 study of two doses of bortezomib in relapsed or refractory myeloma.

In a phase 2 open-label study of the novel proteasome inhibitor bortezomib, 54 patients with multiple myeloma who had relapsed after or were refractory to frontline therapy were randomized to receive intravenous 1.0 or 1.3 mg/m(2) bortezomib twice weekly for 2 weeks, every 3 weeks for a maximum of eight cycles. Dexamethasone was permitted in patients with progressive or stable disease after two or four cycles respectively. Responses were determined using modified European Group for Blood and Marrow Transplantation criteria. The complete response (CR) + partial response (PR) rate for bortezomib alone was 30% [90% confidence interval (CI), 15.7-47.1] and 38% (90% CI, 22.6-56.4) in the 1.0 mg/m(2) (8 of 27 patients) and 1.3 mg/m(2) (10 of 26 patients) groups respectively. The CR + PR rate for patients who received bortezomib alone or in combination with dexamethasone was 37% and 50% for the 1.0 and 1.3 mg/m(2) cohorts respectively. The most common grade 3 adverse events were thrombocytopenia (24%), neutropenia (17%), lymphopenia (11%) and peripheral neuropathy (9%). Grade 4 events were observed in 9% (five of 54 patients). Bortezomib alone or in combination with dexamethasone demonstrated therapeutic activity in patients with multiple myeloma who relapsed after frontline therapy.

Retinoblastoma: the case for radiotherapy and for adjuvant chemotherapy.

The results of treatment for 39 consecutive children with retinoblastoma that was diagnosed between 1951 and 1978 were analyzed. Failure to achieve local control within the eye and the development of metastatic disease occurred in seven patients. These patients are considered individually. Delay in diagnosis, older age at presentation, and extraocular extension of disease at diagnosis were associated with treatment failure and were closely interrelated. Modified radiotherapy techniques using wider fields may prevent failure even in those cases diagnosed late and in those with extraocular extension. Indications for intrathecal and systemic chemotherapy in this disease are discussed.

Osteogenic sarcoma following treatment with megavoltage radiation and chemotherapy for bone tumors in children.

While osteogenic sarcoma has been well-recognized as a late complication of exposure to high doses of ionizing radiation in the orthovoltage energy range, it has been less frequently reported in patients treated with megavoltage radiation. This potential complication should, however, not be dismissed as an occurrence to be seen only after high-dose orthovoltage radiation. We have recently seen two children who developed osteogenic sarcoma following treatment with megavoltage radiation and combination chemotherapy for primary bone tumors. The implications in regard to aggressive multimodality treatment for pediatric malignancies are discussed.