Iodine-131 rituximab radioimmunotherapy with BEAM conditioning and autologous stem cell transplant salvage therapy for relapsed/refractory aggressive non-Hodgkin lymphoma

Radioimmunotherapy-based conditioning regimen prior to autologous stem cell transplantation in non-Hodgkin lymphoma

Non-Hodgkin lymphoma (NHL) is the most common hematologic malignancy and the sixth cause of death from cancer in the USA. Autologous stem cell transplantation (ASCT) is a potentially curative therapeutic option for many NHL patients. Choosing the most effective conditioning regimen prior to ASCT can lead to longer survival in these patients, and, as in many cases of high risk NHL, the only potentially curative option is stem cell transplantation. Radioimmunotherapy (RIT) is based on using radiolabeled monoclonal antibodies against tumoral antigens. Since lymphoma cells are sensitive to radiation, RIT has become a potential approach in treating NHL. In this review, we have discussed the efficacy and safety of RIT as an alternative conditioning regimen prior to ASCT.

Current trials for frontline therapy of mantle cell lymphoma

Mantle cell lymphoma (MCL) is a rare and incurable subtype of non-Hodgkin’s lymphoma that generally affects older individuals. However, the use of high-dose therapy and autologous stem cell transplant has improved significantly the prognosis of this hematological malignancy, but at the cost of increased toxicities, such as acute toxic death and secondary malignancies. But thanks to a rising understanding of the biology of MCL, the explosion of specifically targeted new efficacious agents, immunotherapy agents, and cellular therapies in the frontline setting, the prognosis of MCL is expected to improve dramatically.

The initial treatment of MCL is currently not standardized and the therapeutic landscape of MCL is rapidly evolving. This review provides an extensive overview of the current frontline therapy trials for MCL and presents the results of innovative regimen, including some integrating novel agents and desintensified chemotherapy.

Y90 -Ibritumomab tiuxetan (Y90 -IT) and high-dose melphalan as conditioning regimen before autologous stem cell transplantation for elderly patients with lymphoma in relapse or resistant to chemotherapy: a feasibility trial (SAKK 37/05)

Standard conditioning regimens for autologous stem cell transplantation (ASCT) are often not tolerated by elderly patients, on one hand. Single high-dose melphalan, on the other hand, has been shown to be safe and active as a pretransplant preparative regimen in elderly patients. Y⁹⁰ -Ibritumomab tiuxetan (Y⁹⁰ -IT) is well tolerated and feasible in the transplantation setting. We therefore investigated the combination of high-dose melphalan and Y⁹⁰ -IT as a conditioning regimen for patients ≥65 years of age. Patients with relapsed or resistant CD20-positive lymphoma in remission after salvage chemotherapy could be enrolled. High-dose therapy consisted of standard dose Y⁹⁰ -IT (0.4-mCi/kg body weight) followed by melphalan at escalating doses (100, 140, 170 and 200 mg/m² ) and ASCT. The primary objective was to identify the maximum tolerated dose; secondary end points were complete response (CR) rate 100 days after transplantation and toxicity. Twenty patients (median age 72 years) were included. No DLT occurred at any dose level. Thirteen patients completed the treatment, 11 were evaluable for response. Seven patients did not complete treatment because of mobilization failure (n = 3), progressive disease (n = 2), worsening of cardiac function (n = 1), and grade 3 dyspnea (n = 1). Seven patients achieved a CR/complete remission/unconfirmed (CRu) and 2 had stable disease. Five out of 7 responding patients were still alive more than 3 years after transplantation. The 2 patients with SD had a long-term survival of 3 and 5 years, respectively. Nonhematological grade 3 or higher treatment related adverse events (AEs) were infection (n = 6), including 2 cases of febrile neutropenia, diarrhea (n = 3), mucositis, anorexia, viral hepatitis, hypokalemia, dehydration, and multiorgan failure (n = 1 for each). The combination of Y⁹⁰ -IT and high-dose melphalan is feasible before ASCT for elderly patients, with promising activity and manageable toxicity.

Advancement in high dose therapy and autologous stem cell rescue in lymphoma

Although advanced stage aggressive non-Hodgkin’s lymphomas and Hodgkin’s disease are thought to be chemotherapy-responsive cancers, a considerable number of patients either relapse or never attain a remission. High-dose therapy (HDT) followed by autologous stem cell transplantation (ASCT) is often the only possibility of cure for most of these patients. However, many controversial issues still remain with respect to HDT/ASCT for lymphomas, including its role for, the optimal timing of transplantation, the best conditioning regimen and the potential use of localized radiotherapy or immunologic methods to decrease post-transplant recurrence. Recently, mainly due to the unavailability of carmustine, several novel conditioning protocols have been clinically developed, with the aim of improving the overall outcome by enhancing the anti-lymphoma effect and, at the same time, by reducing short and long-term toxicity. Furthermore, the better safety profiles of novel approaches would definitively allow patients aged more than 65-70 years to benefit from this therapeutic option. In this review, we will briefly discuss the most relevant and recent data available regarding HDT/ASCT in lymphomas.

Trial Watch: Radioimmunotherapy for oncological indications

During the past two decades, it has become increasingly clear that the antineoplastic effects of radiation therapy do not simply reflect the ability of X-, β- and γ-rays to damage transformed cells and directly cause their permanent proliferative arrest or demise, but also involve cancer cell-extrinsic mechanisms. Indeed, among other activities, radiotherapy has been shown to favor the establishment of tumor-specific immune responses that operate systemically, underpinning the so-called 'out-of-field' or 'abscopal' effect. Thus, ionizing rays appear to elicit immunogenic cell death, a functionally peculiar variant of apoptosis associated with the emission of a particularly immunostimulatory combination of damage-associated molecular patterns. In line with this notion, radiation therapy fosters, and thus exacerbates, the antineoplastic effects of various treatment modalities, including surgery, chemotherapy and various immunotherapeutic agents. Here, we summarize recent advances in the use of ionizing rays as a means to induce or potentiate therapeutically relevant anticancer immune responses. In addition, we present clinical trials initiated during the past 12 months to test the actual benefit of radioimmunotherapy in cancer patients.