Maintenance With Rituximab(Drug information on rituximab) Improves Response
In abstract #1175, Dr. John Hainsworth presented results on the treatment of indolent low-grade non-Hodgkin’s lymphoma (NHL) with rituximab (Rituxan) given as induction followed by maintenance cycles every 6 months. Sixty-two patients were entered in this study from 1998 through 1999, and the response rate is very favorable with minimal side effects. Interestingly, the response rate has increased after additional maintenance courses of rituximab, and two thirds of the patients are free of progression at 2 years for both follicular and small lymphocytic histologies. The authors indicated that repeated courses of rituximab at 6-month intervals improved responses in 30% of patients without increasing the toxicity.
Early-Stage Primary Gastric Lymphoma
Abstracts #1186 and #1187, presented by Dr. P. Koch from Germany and Dr. B. Pro from Texas, respectively, discuss results with regard to the treatment of early-stage primary gastric lymphoma with nonsurgical therapies. Dr. Koch presented an analysis of a database of about 370 patients and concluded that primary chemotherapy or a combination of chemotherapy and irradiation is very effective primary therapy and that surgery for these early lesions does not improve outcome, but is associated with toxicity and morbidity due to the effects of gastrectomy. Dr. Pro presented results on 45 patients treated with chemotherapy, with or without radiotherapy for stage I and II gastric lymphoma. Dr. Pro reported that 43 of 45 patients (95%) achieved a complete remission, and the projected 5-year overall disease-specific survival was 90%. Importantly, however, there were two treatment-related deaths (4%), one with sepsis and the other with gastrointestinal bleeding, both of which were on treatment. Dr. Pro concluded that chemotherapy with or without radiation therapy is associated with high response rates and excellent survival in early-stage primary gastric lymphoma, thus avoiding the complications of surgery.
Our impression from these two trials is that primary chemotherapy with or without irradiation is a reasonable option for early-stage primary gastric lymphoma. One has to be very careful, however, and individualize the therapy, particularly in trying to avoid the risk of perforation and local bleeding. These risks are real and need to be considered in a multidisciplinary approach with close consultation with the gastroenterologist and the surgeon.
Primary Paranasal Sinus Lymphoma
Dr. Janessa Laskin from Canada (abstract #1188) presented results on the use of central nervous system (CNS) chemoprophylaxis with intrathecal chemotherapy in patients with primary paranasal sinus lymphoma. This disease is an uncommon presentation of extranodal lymphoma that is associated with a high risk of CNS involvement. Indeed, in this series of 44 patients analyzed retrospectively since 1980, the authors observed that the risk of CNS recurrence or involvement declined from 40% prior to the institution of intrathecal chemotherapy in 1984 down to only 8% after 1984. In fact, intrathecal prophylaxis was also associated with an improvement in overall survival from 20% to 50%.