Baseline total metabolic tumor volume is prognostic for refractoriness to Iimunochemotherapy in DLBCL: results from GOYA

Introduction A good response to initial therapy is key to maximizing survival in patients with diffuse large B-cell lymphoma (DLBCL), but patients with chemorefractory disease and early progression have poor outcomes. Patients and Methods Data from the GOYA study in patients with DLBCL who received first-line rituximab or obinutuzumab plus cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) were analyzed. Positron emission tomography/computed tomography (PET/CT)-derived characteristics associated with total metabolic tumor volume (TMTV) and clinical risk factors for primary chemorefractory disease and disease progression within 12 months (POD12) were explored. Results Of those patients fulfilling the criteria for analysis, 108/1126 (10%) were primary chemorefractory and 147/1106 (13%) had POD12. Primary chemorefractory and POD12 status were strongly associated with reduced overall survival. After multivariable analysis of clinical and imaging-based risk factors by backward elimination, only very high TMTV (quartile [Q] 1 vs. Q4 odds ratio [OR]: 0.45; P = .006) and serum albumin levels (low vs. normal OR of 1.86; P = .004) were associated with primary chemorefractoriness. After additionally accounting for BCL2/MYC translocation in a subset of patients, TMTV and BCL2/MYC double-hit status remained as significant predictors of primary chemorefractoriness (Q1 vs. Q4 OR: 0.32, P = .01 and double-hit vs. no-hit OR of 4.47, P = .02, respectively). Risk factors including very high TMTV, high sum of the product of the longest diameters (SPD), geographic region (Asia), short time since diagnosis, extranodal involvement and low serum albumin were retained for POD12. Conclusion PET-derived TMTV has prognostic value in identifying patients at risk of early treatment failure

Radioimmunotherapy of B-cell lymphoma with radiolabelled anti-CD20 monoclonal antibodies

CD20 has proven to be an excellent target for the treatment of B-cell lymphoma, first for the chimeric monoclonal antibody rituximab (Rituxan™), and more recently for the radiolabelled antibodies Y-90 ibritumomab tiuxetan (Zevalin™) and I-131 tositumomab (Bexxar™). Radiation therapy effects are due to beta emissions with path lengths of 1–5 mm; gamma radiation emitted by I-131 is the only radiation safety issue for either product. Dose-limiting toxicity for both radiolabelled antibodies is reversible bone marrow suppression. They produce response rates of 70%–90% in low-grade and follicular lymphoma and 40%–50% in transformed low-grade or intermediate-grade lymphomas. Both products produce higher response rates than related unlabelled antibodies, and both are highly active in patients who are relatively resistant to rituximab-based therapy. Median duration of response to a single course of treatment is about 1 year with complete remission rates that last 2 years or longer in about 25% of patients. Clinical trials suggest that anti- CD20 radioimmunotherapy is superior to total body irradiation in patients undergoing stem cell supported therapy for B-cell lymphoma, and that it is a safe and efficacious modality when used as consolidation therapy following chemotherapy. Among cytotoxic treatment options, current evidence suggests that one course of anti-CD20 radioimmunotherapy is as efficacious as six to eight cycles of combination chemotherapy. A major question that persists is how effective these agents are in the setting of rituximab- refractory lymphoma. These products have been underutilised because of the complexity of treatment coordination and concerns regarding reimbursement

Review of Bruton Tyrosine Kinase Inhibitors for the Treatment of Relapsed or Refractory Mantle Cell Lymphoma

Mantle cell lymphoma (MCL) is a rare subtype of aggressive B-cell non-Hodgkin lymphoma that remains incurable with standard therapy. Patients typically require multiple lines of therapy, and those with relapsed or refractory (R/R) disease have a very poor prognosis. The Bruton tyrosine kinase (BTK) inhibitor ibrutinib has proven to be an effective agent for patients with R/R MCL. Although usually well tolerated, ibrutinib can be associated with unique toxicities, requiring discontinuation in some patients. Effective and well-tolerated alternatives to ibrutinib for patients with R/R MCL are therefore needed. Novel btk inhibitors such as acalabrutinib, zanubrutinib, and tirabrutinib are designed to improve on the safety and efficacy of first-generation btk inhibitors such as ibrutinib. Data from single-arm clinical trials suggest that, compared with ibrutinib, second-generation btk inhibitors have comparable efficacy and might have a more favourable toxicity profile. Those newer btk inhibitors might therefore provide a viable treatment option for patients with R/R MCL

Emerging Therapies for the Treatment of Relapsed or Refractory Follicular Lymphoma

With no treatment standard having been established for relapsed and refractory follicular lymphoma, a number of therapeutic approaches are used in Canada. In patients who relapse early or who eventually become resistant to subsequent treatment, prognosis is poor, and new approaches are needed. A number of novel therapies are being examined in this setting, including monoclonal antibodies, immunoconjugates, immunomodulatory agents, and signal transduction inhibitors. With the body of evidence for those emerging therapies accumulating and the standard upfront treatment changing from rituximab and chop (cyclophosphamide–doxorubicin–vincristine–prednisone) or rituximab and cvp (cyclophosphamide–vincristine–prednisone) to bendamustine and rituximab, treatment decisions in the relapsed and refractory setting have become more complex. The choice of subsequent treatment must consider type of upfront treatment; duration of remission; and patient-related factors such as age, comorbidities, and treatment preferences. This paper summarizes the evidence for novel therapies and proposes recommendations for subsequent treatment options by remission duration after induction and maintenance

A Canadian perspective on bendamustine for the treatment of chronic lymphocytic leukemia and non-Hodgkin lymphoma

Despite the success of standard treatments in chronic lymphocytic leukemia (cll) and non-Hodgkin lymphoma (nhl), patients are often unable to tolerate aggressive regimens, and they require effective alternatives. Bendamustine is a bifunctional alkylator with unique properties that significantly distinguish it from other agents in its class. In untreated cll, bendamustine has demonstrated rates of response and progression-free survival (pfs) that are superior to those with chlorambucil, with an acceptable toxicity profile. In the relapsed setting, combination treatment with bendamustine–rituximab (br) has demonstrated promising activity in high-risk patients such as those refractory to fludarabine or alkylating agents. In untreated patients with indolent nhl and mantle cell lymphoma, br has demonstrated a pfs significantly longer than that achieved with r-chop (rituximab–cyclophosphamide–doxorubicin–vincristine–prednisone), with significantly reduced toxicity. In the relapsed setting, br has demonstrated rates of response and pfs superior to those with fludarabine–rituximab, with comparable toxicity. In the United States and Europe, bendamustine has been approved for the treatment of cll and indolent nhl; its approval in Canada is pending and eagerly awaited. Once available, bendamustine will benefit many Canadian patients with nhl and cll

Emerging Therapies for the Treatment of Relapsed or Refractory Diffuse Large B Cell Lymphoma

Diffuse large B cell lymphoma (DLBCL) is an aggressive non-Hodgkin lymphoma, accounting for approximately 30% of lymphoma cases in Canada. Although most patients will achieve a cure, up to 40% will experience refractory disease after initial treatment, or relapse after a period of remission. In eligible patients, salvage therapy followed by high-dose therapy and autologous stem-cell transplantation (ASCT) is the standard of care. However, many patients are transplant-ineligible, and more than half of those undergoing asct will subsequently relapse. For those patients, outcomes are dismal, and novel treatment approaches are a critical unmet need. In this paper, we present available data about emerging treatment approaches in the latter setting and provide a perspective about the potential use of those approaches in Canada