The optimal management of follicular lymphoma: an evolving field

Long-term complication in follicular lymphoma: assessing the risk of secondary neoplasm in 242 patients treated or not with 90-yttrium-ibritumomab-tiuxetan

BACKGROUND

Non-Hodgkin lymphoma patients have a 25% increased risk of secondary primary neoplasms (SPNs). Regarding the controversy about the increased risk of SPN in patients exposed to radioimmunotherapy (RIT), we have analyzed this issue in a cohort of follicular lymphoma (FL) patients treated with/without RIT.

PATIENTS AND METHODS

A retrospective study including all consecutive FL patients diagnosed since 2001 was performed. Demographic, clinical data including the incidence of any kind of neoplasm (excluding basocellular skin carcinoma) were recorded.

RESULTS

A total of 242 patients were registered, male/female: 103/139, mean age: 59.9 yr (15-86), stage IV (57.8%), and Follicular Lymphoma Prognostic Index (FLIPI) low-risk (62.15%) predominance. Ninety-six patients (39.7%) were treated with 90Y-IT. The median follow-up for patients treated or not with 90Y-IT was 61 (8-273) and 38 (1-171) months. With respect to SPN incidence, 38 (15.6%) patients have at least two cancers, in 17 (44.7%), FL was the SPN; for the rest (226), the global incidence of SPNs was 9.3% (21), but there were no differences related to the exposition or not to 90Y-IT (P = 0.26). In seven patients, more than two (2-6) different therapies were registered; four were exposed to fludarabine-based therapy, three to radiotherapy and two to autologous stem-cell transplantation, and in the RIT cohort, two patients developed myelodysplastic syndrome.

CONCLUSION

This is one of the largest single institution reports assessing the risk of SPN in FL patients treated (96) or not (146) with 90Y-IT. It seems that 90Y-IT does not increase significantly the risk of SPN but avoiding its use after fludarabine and other intense cytotoxic schemes is recommended.

Combretastatins: more than just vascular targeting agents?

Several prodrugs of the naturally occurring combretastatins have undergone extensive clinical evaluation as vascular targeting agents (VTAs). Their increased selectivity toward endothelial cells together with their innate ability to rapidly induce vascular shutdown and inhibit tumor growth at doses up to 10-fold less than the maximum tolerated dose led to the clinical evaluation of combretastatins as VTAs. Tubulin is well established as the molecular target of the combretastatins and the vast majority of its synthetic derivatives. Furthermore, tubulin is a highly validated molecular target of many direct anticancer agents routinely used as front-line chemotherapeutics. The unique vascular targeting properties of the combretastatins have somewhat overshadowed their development as direct anticancer agents and the delineation of the various cell death pathways and anticancer properties associated with such chemotherapeutics. Moreover, the ongoing clinical trial of OXi4503 (combretastatin-A1 diphosphate) together with preliminary preclinical evaluation for the treatment of refractory acute myelogenous leukemia has successfully highlighted both the indirect and direct anticancer properties of combretastatins. In this review, we discuss the development of the combretastatins from nature to the clinic. The various mechanisms underlying combretastatin-induced cell cycle arrest, mitotic catastrophe, cell death, and survival are also reviewed in an attempt to further enhance the clinical prospects of this unique class of VTAs.

Is the traditional Chinese medicine helpful for patients with hematologic malignant diseases? A meta-analysis of randomized controlled trials

AIM: To evaluate the efficacy of traditional Chinese medicine (TCM) for the treatment of hematologic malignant diseases.

METHODS: We searched the Cochrane CENTRAL, PubMed, Embase, Web of Science, AMED, CNKI, Wanfang Platform; China Sinomed and the clinical trial registry web sites and Googlescholar electronically up to June 19^th, 2014 and hand searched related publications. Only randomized controlled trials (RCTs) researching on whether TCM as the adjuvant treatment improved the effect for hematologic malignant diseases were included. Two reviewers extracted data and evaluated the studies independently. Pooled risk ratios (RR) were calculated as outcome measures. Our primary outcomes were the overall response (OR) rate.

RESULTS: We retrieved 13143 references and included 11 RCTs involved 891 participants after screening. Because the non-significant heterogeneity we used the fixed effect model to combine data and TCM had a significantly higher OR and CR (complete response) rates than the control [RR = 1.17, 95%CI: (1.10, 1.25), P < 0.00001; RR = 1.24, 95%CI: (1.11, 1.37), P < 0.0001, respectively]. Only three studies included in the survival rate analysis. We combined them with random effects model and there was no significant difference between the TCM and control arms. Because of the low heterogeneity we used the fixed effect model to combine the non-hematologic adverse effects (AEs) data. Our results showed that TCM significantly decreased non-hematologic AEs rates we researched, the gastrointestinal reaction [RR = 0.50, 95%CI: (0.37, 0.68), P < 0.0001], liver and/or kidney injury [RR = 0.37, 95%CI: (0.26, 0.53), P < 0.00001] and heart injury [RR = 0.24, 95%CI: (0.09, 0.68), P = 0.007]. Additionally, TCM had a trend to decrease the infection rate [RR = 0.16, (0.02, 1.12), P = 0.07], but not statistically significantly.

CONCLUSION: TCM increases OR and CR rates for hematologic malignances and reduces treatment associated serious non-hematologic AEs. Therefore, TCM should be included in the treatment of hematologic malignances.

BCL2 mutations are associated with increased risk of transformation and shortened survival in follicular lymphoma

Follicular lymphoma (FL), an indolent neoplasm caused by a t(14;18) chromosomal translocation that juxtaposes the BCL2 gene and immunoglobulin locus, has a variable clinical course and frequently undergoes transformation to an aggressive lymphoma. Although BCL2 mutations have been previously described, their relationship to FL progression remains unclear. In this study, we evaluated the frequency and nature of BCL2 mutations in 2 independent cohorts of grade 1 and 2 FLs, along with the correlation between BCL2 mutations, transformation risk, and survival. The prevalence of BCL2 coding sequence mutations was 12% in FL at diagnosis and 53% at transformation (P < .0001). The presence of these BCL2 mutations at diagnosis correlated with an increased risk of transformation (hazard ratio 3.6; 95% CI, 2.0-6.2; P < .0001) and increased risk of death due to lymphoma (median survival of 9.5 years with BCL2 mutations vs 20.4 years without; P = .012). In a multivariate analysis, BCL2 mutations and high FL international prognostic index were independent risk factors for transformation and death due to lymphoma. Some mutant Bcl-2 proteins exhibited enhanced antiapoptotic capacity in vitro. Accordingly, BCL2 mutations can affect antiapoptotic Bcl-2 function, are associated with increased activation-induced cytidine deaminase expression, and correlate with increased risk of transformation and death due to lymphoma.

Radioimmunotherapy combined with maintenance anti-CD20 antibody may trigger long-term protective T cell immunity in follicular lymphoma patients

Growing evidence suggests that the patient's immune response may play a major role in the long-term efficacy of antibody therapies of follicular lymphoma (FL). Particular long-lasting recurrence free survivals have been observed after first line, single agent rituximab or after radioimmunotherapy (RIT). Rituximab maintenance, furthermore, has a major efficacy in prolonging recurrence free survival after chemotherapy. On the other hand, RIT as a single step treatment showed a remarkable capacity to induce complete and partial remissions when applied in recurrence and as initial treatment of FL or given for consolidation. These clinical results strongly suggest that RIT combined with rituximab maintenance could stabilize the high percentages of patients with CR and PR induced by RIT. While the precise mechanisms of the long-term efficacy of these 2 treatments are not elucidated, different observations suggest that the patient's T cell immune response could be decisive. With this review, we discuss the potential role of the patient's immune system under rituximab and RIT and argue that the T cell immunity might be particularly promoted when combining the 2 antibody treatments in the early therapy of FL.