Prolonged survival in the absence of disease-recurrence in advanced-stage follicular lymphoma following chemo-immunotherapy: 13-year update of the prospective, multicenter randomized GITMO-IIL trial

Measurable Residual Disease Monitoring in Lymphoma

PURPOSE OF REVIEW

The utility of analyzing circulating tumor DNA (ctDNA), circulating tumor cells (CTCs), and disease in the bone marrow as an adjunctive tool in caring for hematologic cancer patients is expanding. This holds true for lymphoma where these biomarkers are being explored as a means of genotyping and quantifying disease. Regarding the latter, they can be used to monitor measurable residual disease (MRD) during and after treatment. This holds potential for aiding clinical decisions amidst treatment, detecting earlier relapse, and improving prognostication. Here, we review the evidence to support these applications in a variety of lymphoma subtypes.

RECENT FINDINGS

Numerous clinical trials across a variety of lymphomas have demonstrated value in MRD monitoring. MRD monitoring is often prognostic for progression free survival (PFS) and even overall survival (OS) at several time points in a disease course, particularly when utilizing serial measurements. With regards to tailoring treatment, there are a growing number of trials examining MRD-adaptive treatment strategies to intensify or de-escalate treatment to individualize care. Lastly, MRD monitoring has been utilized successfully in detecting earlier relapse when compared to more standard methods of clinical surveillance such as radiographic assessment. Although not routinely implemented into clinical practice, MRD monitoring in lymphoma is helping shape the future landscape of this disease by aiding in prognostication, guiding therapy, and detecting earlier relapse. Steps to standardize and further examine this technology prospectively are being taken to bring MRD monitoring to the forefront of the field.

Real-world evidence on venetoclax in chronic lymphocytic leukemia: The Italian experience

Chronic lymphocytic leukemia (CLL) is the most common form of adult leukemia in the western world. In Italy, venetoclax was approved for use in patients with CLL as monotherapy in 2017 and in combinations in 2019. As a result of this delayed approval, there are relatively few real-world studies from Italian clinical practice and much of the data are in heavily pretreated patients. We have collected the available studies in Italian routine practice. Three studies confirm the effectiveness and tolerability of this agent in patients with relapsed/refractory CLL and high-risk disease characteristics, many of whom had received prior B-cell receptor signaling treatment. Addition of rituximab to venetoclax produced more complete responses in patients with relapsed/refractory CLL, while higher disease burden and progression while receiving a prior Bruton's tyrosine kinase inhibitor were both associated with poorer outcomes in patients treated with venetoclax. Venetoclax was well-tolerated with low discontinuation rates. No studies of venetoclax plus obinutuzumab for the first-line treatment of patients with CLL were available due to the short time since approval in Italy. Several cohorts addressed the impact of COVID-19 on patient management and outcomes, suggesting that treated patients and those in clinical observation had similar rates of COVID-19-related hospital admission, intensive care unit admission, and mortality. Overall, the responses and tolerance to venetoclax observed in the Italian real-world setting confirm the tolerability and effectiveness of venetoclax regimens in high-risk patients.

Long-term follow-up demonstrates curative potential of autologous stem cell transplantation for relapsed follicular lymphoma

Although autologous stem cell transplantation (ASCT) can achieve durable responses in eligible patients with follicular lymphoma (FL), long-term follow-up is needed to determine if it has curative potential. This retrospective, multicenter study included 162 patients who received ASCT for relapsed FL in Alberta, Canada. With a median (range) follow-up time of 12.5 years (0.1-27.9), the 12-year time-to-progression (TTP) was 57% (95% confidence interval [CI] 49%-65%), time-to-next-treatment was 61% (95% CI 52%-69%), progression-free survival was 51% (95% CI 42%-59%) and overall survival was 69% (95% CI 60%-76%). A plateau emerged on the TTP curve at 57% starting 9 years after ASCT with no relapses occurring beyond this timepoint. Ten patients remained in remission 20 years or more after ASCT. Patients undergoing ASCT at first or second relapse had superior outcomes compared to third or later relapse (12-year TTP 61% vs. 34%), as did patients without progression of disease within 24 months (POD24) of frontline treatment versus those with POD24 (12-year TTP 67% vs. 50%). ASCT achieves high rates of durable remission in relapsed FL, with long-term follow-up revealing that more than 50% of transplanted patients may be functionally cured of their lymphoma. The optimal timing to consider ASCT is at first or second relapse, regardless of POD24 status.

Achieving the Cure of Follicular Lymphoma: is it Time to Finalize Treatment Strategies to Reach This Goal in a Subset of Patients?

NO ABSTRACT AVAILABLE

Tisagenlecleucel in adult relapsed or refractory follicular lymphoma: the phase 2 ELARA trial

Tisagenlecleucel is an autologous anti-CD19 chimeric antigen receptor-T cell therapy with clinically meaningful outcomes demonstrated in patients with relapsed/refractory (r/r) B-cell lymphoma. In a previous pilot study of tisagenlecleucel in r/r follicular lymphoma (FL), 71% of patients achieved a complete response (CR). Here we report the primary, prespecified interim analysis of the ELARA phase 2 multinational trial of tisagenlecleucel in adults with r/r FL after two or more treatment lines or who relapsed after autologous stem cell transplant (no. NCT03568461). The primary endpoint was CR rate (CRR). Secondary endpoints included overall response rate (ORR), duration of response, progression-free survival, overall survival, pharmacokinetics and safety. As of 29 March 2021, 97/98 enrolled patients received tisagenlecleucel (median follow-up, 16.59 months; interquartile range, 13.8-20.21). The primary endpoint was met. In the efficacy set (n = 94), CRR was 69.1% (95% confidence interval, 58.8-78.3) and ORR 86.2% (95% confidence interval, 77.5-92.4). Within 8 weeks of infusion, rates of cytokine release syndrome were 48.5% (grade ≥3, 0%), neurological events 37.1% (grade ≥3, 3%) and immune effector cell-associated neurotoxicity syndrome (ICANS) 4.1% (grade ≥3, 1%) in the safety set (n = 97), with no treatment-related deaths. Tisagenlecleucel is safe and effective in extensively pretreated r/r FL, including in high-risk patients.

Does MRD have a role in the management of iNHL?

Among indolent non-Hodgkin lymphomas (iNHLs), the analysis of measurable/minimal residual disease (MRD) has been extensively applied to follicular lymphoma (FL). Treatment combinations have deeply changed over the years, as well as the techniques to measure MRD, which is currently evaluated only in the setting of clinical trials. Here, we discuss the evidence on the role of molecular monitoring in the management of FL. Mature data support the quantification of molecular tumor burden at diagnosis as a tool to stratify patients in risk categories and of MRD evaluation at the end of treatment to predict progression-free survival and overall survival. Moreover, MRD deserves further studies as a tool to refine the clinical/metabolic response and to modulate treatment intensity/duration. Patients with a higher relapse probability can be identified, but the relevance of continuous molecular follow-up should be clarified by kinetic models of MRD analysis. Being the BCL2/heavy chain immunoglobulin gene hybrid rearrangement detectable in about 50% to 60% of advanced FL and in 30% of positron emission tomography/computed tomography-staged localized FL, technical advancements such as next-generation sequencing/target locus amplification may allow broadening the FL population carrying a molecular marker. Droplet digital polymerase chain reaction can better quantify MRD at low levels, and novel sources of DNA, such as cell-free DNA, may represent a noninvasive tool to monitor MRD. Finally, MRD in other iNHLs, such as lymphoplasmacytic lymphoma/Waldenström macroglobulinemia and marginal zone lymphoma, is beginning to be explored.

Long-term outcome in patients with follicular lymphoma following high-dose therapy and autologous stem cell transplantation

OBJECTIVE

To contribute data on long-term outcome and potential curative impact of ASCT in FL, especially following HDT with the BEAM protocol (BCNU, etoposide, cytarabine and melphalan), given very limited data on this topic in the literature.

PATIENTS AND METHODS

Patients with FL (n = 76) were treated in our institution with HDT and ASCT. In the case of long-term remission (≥8 years), peripheral blood was tested for minimal residual disease by t(14;18)- and IGH-PCR, including the last follow-up.

RESULTS

10-year overall survival, progression-free survival, and freedom from progression (FFP) after first-line ASCT (n = 20) were 80%, 60%, and 69%, after second-line ASCT (n = 48, following BEAM) 66%, 38%, and 41%, after third/fourth-line ASCT (n = 8) 33%, 25%, and 25%, respectively. Prognostic factors for FFP were treatment line and FLIPI (Follicular Lymphoma International Prognostic Index). 10-year FFP for second-line ASCT and low-risk FLIPI at relapse was 69%, intermediate-risk 28%, and high-risk 25% (P < .05). 26 patients developed sustained long-term clinical and molecular remissions of up to 27 years.

CONCLUSIONS

Sustained long-term clinical and molecular complete remissions up to 27 years can be achieved following ASCT (including HDT with BEAM in second treatment line), indicating a potential curative impact of ASCT in FL.

Evaluating upfront high-dose consolidation after R-CHOP for follicular lymphoma by clinical and genetic risk models

High-dose therapy and autologous stem cell transplantation (HDT/ASCT) is an effective salvage treatment for eligible patients with follicular lymphoma (FL) and early progression of disease (POD). Since the introduction of rituximab, HDT/ASCT is no longer recommended in first remission. We here explored whether consolidative HDT/ASCT improved survival in defined subgroups of previously untreated patients. We report survival analyses of 431 patients who received frontline rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) for advanced FL, and were randomized to receive consolidative HDT/ASCT. We performed targeted genotyping of 157 diagnostic biopsies, and calculated genotype-based risk scores. HDT/ASCT improved failure-free survival (FFS; hazard ratio [HR], 0.8, P = .07; as-treated: HR, 0.7, P = .04), but not overall survival (OS; HR, 1.3, P = .27; as-treated: HR, 1.4, P = .13). High-risk cohorts identified by FL International Prognostic Index (FLIPI), and the clinicogenetic risk models m7-FLIPI and POD within 24 months-prognostic index (POD24-PI) comprised 27%, 18%, and 22% of patients. HDT/ASCT did not significantly prolong FFS in high-risk patients as defined by FLIPI (HR, 0.9; P = .56), m7-FLIPI (HR, 0.9; P = .91), and POD24-PI (HR, 0.8; P = .60). Similarly, OS was not significantly improved. Finally, we used a machine-learning approach to predict benefit from HDT/ASCT by genotypes. Patients predicted to benefit from HDT/ASCT had longer FFS with HDT/ASCT (HR, 0.4; P = .03), but OS did not reach statistical significance. Thus, consolidative HDT/ASCT after frontline R-CHOP did not improve OS in unselected FL patients and subgroups selected by genotype-based risk models.

The Oral Microbiome and Cancer

There is mounting evidence that members of the human microbiome are highly associated with a wide variety of cancer types. Among oral cancers, oral squamous cell carcinoma (OSCC) is the most prevalent and most commonly studied, and it is the most common malignancy of the head and neck worldwide. However, there is a void regarding the role that the oral microbiome may play in OSCC. Previous studies have not consistently found a characteristic oral microbiome composition associated with OSCC. Although a direct causality has not been proven, individual members of the oral microbiome are capable of promoting various tumorigenic functions related to cancer development. Two prominent oral pathogens, Porphyromonas gingivalis, and Fusobacterium nucleatum can promote tumor progression in mice. P. gingivalis infection has been associated with oro-digestive cancer, increased oral cancer invasion, and proliferation of oral cancer stem cells. The microbiome can influence the evolution of the disease by directly interacting with the human body and significantly altering the response and toxicity to various forms of cancer therapy. Recent studies have shown an association of certain phylogenetic groups with the immunotherapy treatment outcomes of certain tumors. On the other side of the coin, recently it has been a resurgence in interest on the potential use of bacteria to cure cancer. These kinds of treatments were used in the late nineteenth and early twentieth centuries as the first line of defense against cancer in some hospitals but later displaced by other types of treatments such as radiotherapy. Currently, organisms such as Salmonella typhimurium and Clostridium spp. have been used for targeted strategies as potential vectors to treat cancer. In this review, we briefly summarize our current knowledge of the role of the oral microbiome, focusing on its bacterial fraction, in cancer in general and in OSCC more precisely, and a brief description of the potential use of bacteria to target tumors.

Treatment Patterns and Health Care Costs in Commercially Insured Patients with Follicular Lymphoma

BACKGROUND

Few studies have estimated the real-world economic burden such as all-cause and follicular lymphoma (FL)-related costs and health care resource utilization (HCRU) in patients with FL.

OBJECTIVES

This study evaluated outcomes in patients who were newly initiated with FL indicated regimens by line of therapy with real-world data.

METHODS

A retrospective study was conducted among patients with FL from MarketScan^® databases between January 1, 2010 and December 31, 2013. Patients were selected if they were ≥18 years old when initiated on a FL indicated therapy, had at least 1 FL-related diagnosis, ≥1 FL commonly prescribed systemic anti-cancer therapy after diagnosis, and did not use any FL indicated regimen in the 24 months prior to the first agent. These patients were followed up at least 48 months and the outcomes, including the distribution of regimens by line of therapy, the treatment duration by line of therapy, all-cause and FL-related costs, and HCRU by line of therapy were evaluated.

RESULTS

This study identified 598 patients who initiated FL indicated treatment. The average follow-up time was approximately 5.7 years. Of these patients, 50.2% (n=300) were female, with a mean age of 60.7 years (SD=13.1 years) when initiating their treatment with FL indicated regimens. Overall, 598 (100%) patients received first-line therapy, 180 (43.6%) received second-line therapy, 51 received third-line therapy, 21 received fourth-line therapy, and 10 received fifth-line therapy. Duration of treatment by each line of therapy was 370 days, 392 days, 162 days, 148 days, and 88 days, respectively. The most common first-line regimens received by patients were rituximab (n=201, 33.6%), R-CHOP (combination of rituximab, cyclophosphamide, doxorubicin hydrochloride [hydroxydaunomycin]; n=143, 24.0%), BR (combination of bendamustine and rituximab; n=143, 24.0%), and R-CVP (combination of rituximab, cyclophosphamide, vincristine, and prednisone; n=71, 11.9%). The most common second-line treatment regimens were (N=180): rituximab (n=78, 43.3%) and BR (n=41, 22.8%). Annualized all-cause health care costs per patient ranged from US$97 141 (SD: US$144 730) for first-line to US$424 758 (SD: US$715 028) for fifth-line therapy.

CONCLUSIONS

The primary regimens used across treatment lines conform to those recommended by the National Comprehensive Cancer Network clinical practice guidelines. The economic burden for patients with FL is high and grows with subsequent lines of therapy.

The Oral Microbiome and Cancer

There is mounting evidence that members of the human microbiome are highly associated with a wide variety of cancer types. Among oral cancers, oral squamous cell carcinoma (OSCC) is the most prevalent and most commonly studied, and it is the most common malignancy of the head and neck worldwide. However, there is a void regarding the role that the oral microbiome may play in OSCC. Previous studies have not consistently found a characteristic oral microbiome composition associated with OSCC. Although a direct causality has not been proven, individual members of the oral microbiome are capable of promoting various tumorigenic functions related to cancer development. Two prominent oral pathogens, Porphyromonas gingivalis, and Fusobacterium nucleatum can promote tumor progression in mice. P. gingivalis infection has been associated with oro-digestive cancer, increased oral cancer invasion, and proliferation of oral cancer stem cells. The microbiome can influence the evolution of the disease by directly interacting with the human body and significantly altering the response and toxicity to various forms of cancer therapy. Recent studies have shown an association of certain phylogenetic groups with the immunotherapy treatment outcomes of certain tumors. On the other side of the coin, recently it has been a resurgence in interest on the potential use of bacteria to cure cancer. These kinds of treatments were used in the late nineteenth and early twentieth centuries as the first line of defense against cancer in some hospitals but later displaced by other types of treatments such as radiotherapy. Currently, organisms such as Salmonella typhimurium and Clostridium spp. have been used for targeted strategies as potential vectors to treat cancer. In this review, we briefly summarize our current knowledge of the role of the oral microbiome, focusing on its bacterial fraction, in cancer in general and in OSCC more precisely, and a brief description of the potential use of bacteria to target tumors.