Relapse Timing Is Associated With Distinct Evolutionary Dynamics in Diffuse Large B-Cell Lymphoma

PURPOSE

Diffuse large B-cell lymphoma (DLBCL) is cured in more than 60% of patients, but outcomes remain poor for patients experiencing disease progression or relapse (refractory or relapsed DLBCL [rrDLBCL]), particularly if these events occur early. Although previous studies examining cohorts of rrDLBCL have identified features that are enriched at relapse, few have directly compared serial biopsies to uncover biological and evolutionary dynamics driving rrDLBCL. Here, we sought to confirm the relationship between relapse timing and outcomes after second-line (immuno)chemotherapy and determine the evolutionary dynamics that underpin that relationship.

PATIENTS AND METHODS

Outcomes were examined in a population-based cohort of 221 patients with DLBCL who experienced progression/relapse after frontline treatment and were treated with second-line (immuno)chemotherapy with an intention-to-treat with autologous stem-cell transplantation (ASCT). Serial DLBCL biopsies from a partially overlapping cohort of 129 patients underwent molecular characterization, including whole-genome or whole-exome sequencing in 73 patients.

RESULTS

Outcomes to second-line therapy and ASCT are superior for late relapse (>2 years postdiagnosis) versus primary refractory (<9 months) or early relapse (9-24 months). Diagnostic and relapse biopsies were mostly concordant for cell-of-origin classification and genetics-based subgroup. Despite this concordance, the number of mutations exclusive to each biopsy increased with time since diagnosis, and late relapses shared few mutations with their diagnostic counterpart, demonstrating a branching evolution pattern. In patients with highly divergent tumors, many of the same genes acquired new mutations independently in each tumor, suggesting that the earliest mutations in a shared precursor cell constrain tumor evolution toward the same genetics-based subgroups at both diagnosis and relapse.

CONCLUSION

These results suggest that late relapses commonly represent genetically distinct and chemotherapy-naïve disease and have implications for optimal patient management.

Outcome of limited-stage nodular lymphocyte-predominant Hodgkin lymphoma and the impact of a PET-adapted approach

Radiotherapy (RT) is typically incorporated into the treatment of limited-stage nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL), although it remains unknown whether chemotherapy alone may be suitable in select patients. We evaluated outcomes of limited-stage NLPHL at BC Cancer on the basis of era-specific guidelines: routine RT era, 1995 to 2005 (n = 36), combined modality with 2 cycles of doxorubicin, bleomycin, vinblastine, dacarbazine (ABVD) chemotherapy followed by RT or RT alone; positron emission tomography (PET) era, after 2005 (n = 63), ABVD alone (4 cycles) if the PET scan after the second cycle of ABVD (PET2) is negative, or treatment is changed to RT if PET2 is positive. Median age of patients was 38 years (range, 16-82 years), 73% were male, and 43% had stage II. With a median follow-up of 10.5 years for all patients, 5-year progression-free survival (PFS) was 91% [corrected] and was 97% for overall survival (OS), with no difference by treatment era (PFS, P = .15; [corrected] OS, P = .35). For the 49 patients who had a PET2 scan, 86% were PET negative and 14% were PET positive by Deauville criteria with 5-year PFS rates of 92% and 80% (P = .87) [corrected], respectively. This is the largest study of a PET-adapted approach in NLPHL and supports that ABVD alone may be a viable option in select patients with a negative PET2 scan, with consideration of acute and long-term toxicities.

Pathobiology of nodal peripheral T-cell lymphomas: current understanding and future directions

Predominantly nodal is the most common clinical presentation of peripheral T- (and NK-) cell lymphomas (PTCL), which comprise three main groups of diseases: (i) systemic anaplastic large cell lymphomas (ALCL), whether positive or negative for anaplastic lymphoma kinase (ALK); (ii) follicular helper T-cell lymphomas (TFHL); and (iii) PTCL, not otherwise specified (NOS). Recent advances in the genomic and molecular characterization of PTCL, with enhanced understanding of pathobiology, have translated into significant updates in the latest 2022 classifications of lymphomas. ALK-negative ALCL is now recognized to be genetically heterogeneous, with identification of DUSP22 rearrangements in approximately 20-30% of cases, correlated with distinctive pathological and biological features. The notion of cell-of-origin as an important determinant of the classification of nodal PTCL is best exemplified by TFHL, considered as one disease or a group of related entities, sharing oncogenic pathways with frequent recurrent epigenetic mutations as well as a relationship to clonal hematopoiesis. Data are emerging to support that a similar cell-of-origin concept might be relevant to characterize meaningful subgroups within PTCL, NOS, based on cytotoxic and/or Th1 versus Th2 signatures. The small group of primary nodal Epstein-Barr virus-positive lymphomas of T- or NK-cell derivation, formerly considered PTCL, NOS, is now classified separately, due to distinctive features, and notably an aggressive course. This review summarizes current knowledge of the pathology and biology of nodal-based PTCL entities, with an emphasis on recent findings and underlying oncogenic mechanisms.

Brentuximab vedotin with chemotherapy for stage 3/4 classical Hodgkin lymphoma: Three-year update of the ECHELON-1 study

7532

Background: The phase 3 ECHELON-1 study demonstrated that BV with AVD (A+AVD) was superior to ABVD for the frontline treatment of Stage 3/4 cHL. Maturing data from RATHL and SWOG S0816 show limitations to PET2-adapted strategies, including short and long-term toxicities in PET2+ patients (pts) switched to BEACOPP and still frequent relapse in PET2- pts. Pts in the RATHL trial with Stage 3/4 disease ≤60 yrs had a 3-yr PFS of 79.8% (82.1% PET2-); SWOG S0816 reported a 5-yr PFS of 74% (76% PET2-) in the same population. As an alternative to PET-adapted therapy, here we present a 3-year update of the ECHELON-1 study, including ITT PFS and outcomes by PET status. Methods: Pts with Stage 3/4 cHL were randomized 1:1 to receive up to six cycles of A+AVD (n=664) or ABVD (n=670). Interim PET scan after cycle 2 was conducted. All analyses of PFS are exploratory and per investigator assessment. Results: At a median follow-up of 37 months, analysis of PFS in the ITT population favors the A+AVD treatment arm (Table), with a 3-yr PFS of 83.1% for A+AVD vs 76.0% for ABVD; the 3-yr PFS for PET2- pts <60 yrs was 87.2% vs 81.0%, respectively. Trend toward benefit for PET2+ pts <60 yrs treated with A+AVD was also observed, with a 3-yr PFS of 69.2% vs 54.7% with ABVD. Data from prespecified subgroups and safety follow-up, including peripheral neuropathy, will be presented. Conclusions: Follow-up at 3-yrs demonstrates that frontline treatment of Stage 3/4 cHL with A+AVD provides a durable treatment benefit vs ABVD that is independent of PET2 status. While direct comparisons cannot be made, A+AVD compares favorably to PET-adapted strategies without requiring interim PET assessment, escalation of therapy, or bleomycin. Clinical trial information: NCT01712490. [Table: see text]

Outcome of elderly patients with classical Hodgkin lymphoma (HL) in British Columbia

8031

Background: Outcomes in elderly patients (pts) with Hodgkin lymphoma (HL) have traditionally been poor. We evaluated the survival of elderly pts (>60 years [y]) with classical HL in British Columbia (BC). Methods: All pts aged >60 y newly diagnosed with classical HL from 1961 to 2019 were identified in the BC Cancer Lymphoid Cancer Database. Limited stage was defined as non-bulky (<10 cm) stage 1A/IB or 2A (before 2000 1B = advanced stage), with the remainder considered advanced stage. Results: Following exclusions (HIV positive n=4, incomplete data n=21, prior or concurrent other lymphoproliferative disease n=67), 713 pts were identified. With a median follow up of 6.0 y (0.1 - 24.0 y) in living pts, there has been an improvement in 5 y DSS/OS (both p<.001) by decade comparison: 1960s (n=52) 25%/17%; 1970s (n=75) 38%/31%; 1980s (n=90) 51%/43%; 1990s (n=115) 53%/42%; 2000s (n=180) 66%/57%; 2010s (n=201) 63%/53%. To account for advances in diagnosis, staging, supportive care, and therapy in the modern era, we evaluated the outcome of pts diagnosed since 01/1995. A total of 368 pts were treated with curative intent (Table). Most pts received multi-agent chemotherapy (n=359, 98%: ABVD[like] n=351, alkylator-based n=7, CHOP n=1), 8 pts had radiotherapy (RT) alone, and 1 pt had surgery (primary CNS HL). The 5 y DSS, PFS, and OS were 74%, 57%, and 62%, respectively. Increasing age was associated with inferior outcomes (5 y DSS/PFS/OS): 61-70 y (81%/70%/74%), 71-80 y (69%/47%/52%), and >80 y (59%/27%/31%) (DSS p=.011; PFS p<.0001; OS p<.0001). Of 318 pts that received bleomycin, 60 (19%) developed pulmonary toxicity, including 22 cases that occurred after cycles 1 and 2. Overall, 24/368 pts (7%) died of acute treatment toxicity (pulmonary [bleomycin n=10, radiation n=1], infection n=10, cardiac n=3). There was no association between age and developing bleomycin (p=.80) or lethal treatment toxicities (p=.74). Conclusions: The outcome of elderly pts with HL has improved in recent decades. However, treatment related toxicity remains a concern and use of multi-agent chemotherapy, particularly bleomycin-containing regimens, should be undertaken with caution. [Table: see text]

Positron-emission tomography-based staging is cost-effective in early-stage follicular lymphoma

The objective was to assess the cost-effectiveness of staging PET/CT in early-stage follicular lymphoma (FL) from the Canadian health-care system perspective. Methods: The study population was FL patients staged as early-stage using conventional CT imaging and planned for curative-intent radiation therapy (RT). A decision analytic model simulated the management after adding staging PET/CT versus using staging CT alone. In the no-PET/CT strategy, all patients proceeded to curative-intent RT as planned. In the PET/CT strategy, PET/CT information could result in an increased RT volume, switching to a noncurative approach, or no change in RT treatment as planned. The subsequent disease course was described using a state-transition cohort model over a 30-y time horizon. Diagnostic characteristics, probabilities, utilities, and costs were derived from the literature. Baseline analysis was performed using quality-adjusted life years (QALYs), costs (2019 Canadian dollars), and the incremental cost-effectiveness ratio. Deterministic sensitivity analyses were conducted, evaluating net monetary benefit at a willingness-to-pay threshold of $100,000/QALY. Probabilistic sensitivity analysis using 10,000 simulations was performed. Costs and QALYs were discounted at a rate of 1.5%. Results: In the reference case scenario, staging PET/CT was the dominant strategy, resulting in an average lifetime cost saving of $3,165 and a gain of 0.32 QALYs. In deterministic sensitivity analyses, the PET/CT strategy remained the preferred strategy for all scenarios supported by available data. In probabilistic sensitivity analysis, the PET/CT strategy was strongly dominant in 77% of simulations (i.e., reduced cost and increased QALYs) and was cost-effective in 89% of simulations (i.e., either saved costs or had an incremental cost-effectiveness ratio below $100,000/QALY). Conclusion: Our analysis showed that the use of PET/CT to stage early-stage FL patients reduces cost and improves QALYs. Patients with early-stage FL should undergo PET/CT before curative-intent RT.

Characteristics and Outcome of Extranodal NK/T-cell Lymphoma in North America: A Retrospective Multi-Institutional Experience

BACKGROUND

Extranodal natural killer/T-cell lymphoma (ENKTL) is rare and clinical data from non-Asian countries are lacking. It is unclear whether outcomes and disease natural history is similar to reported Asian series. We assessed characteristics and outcomes of patients with ENKTL from major North American centers.

PATIENTS AND METHODS

We retrospectively identified patients with newly-diagnosed CD56 + ENKTL and studied disease characteristics and clinical outcomes.

RESULTS

One hundred and twenty-one patients with ENKTL diagnosed between June 1990 and November 2012 were identified. Eighty-three patients (69%) had stage I/II disease and were treated with combined modality therapy (CMT) (n = 53), chemotherapy alone (CT) (n = 14) or radiotherapy alone (RT) (n = 16).  Thirty-eight patients (31%) had stage III/IV disease and were treated with CMT (n = 12), CT (n = 23), or RT (n = 3).  The median follow-up for the entire cohort was 51 months. Patients with stage I/II disease, compared to those with stage III/IV disease, had superior 2-year progression free survival (PFS) 43% vs 19% (P = .03) and overall survival (OS) 59% vs. 29% (P= .004). Outcomes were similar for stage I/II patients who received CMT vs. RT alone with 2-year PFS (53% vs. 47%; P= .91) and OS (67% vs. 67%; P= .58). No significant differences in outcomes were noted based on race/ethnicity.

CONCLUSIONS

This series represents a large experience of ENKTL treated at several major North American academic centers.  Our data are consistent with Asian studies: (1) majority of patients present with early-stage disease; (2) overall poor outcome regardless of race/ethnicity; (3) CMT likely yields favorable outcomes for suitable candidates with early-stage disease.

Tislelizumab, a PD-1 inhibitor for relapsed/refractory mature T/NK-cell neoplasms: Results from a phase 2 study

7552

Background: Effective treatment choices for patients (pts) with relapsed/refractory (R/R) mature T/NK-cell neoplasms after failure of standard therapies are limited. Tislelizumab (TIS), a humanized anti-PD-1 mAb, demonstrated outstanding efficacy and favorable safety in pts with R/R classical Hodgkin lymphoma or solid tumors. We present safety and efficacy of the phase 2 study of TIS in pts with R/R mature T/NK-cell neoplasms. Methods: Pts were enrolled into 3 cohorts stratified by the type of T/NK-cell neoplasm to receive TIS 200 mg intravenously every 3 weeks until disease progression or intolerable toxicity. Eligible pts had ≥1 prior systemic therapy, disease progression during/after most recent therapy completion or refractory disease, ECOG ≤2, and life expectancy ≥6 mo. Primary endpoint was investigator-assessed overall response rate (ORR). Secondary endpoints included duration of response (DoR), complete response (CR) rate, progression-free survival (PFS), overall survival (OS) in cohorts 1 and 2, and safety. Results: 77 pts were treated. Cohort 1: R/R extranodal NK/T-cell lymphoma (n = 22); cohort 2: R/R mature T-cell neoplasms (n = 44; 21 peripheral T-cell lymphoma not otherwise specified; 11 angioimmunoblastic T-cell lymphoma; 12 anaplastic large cell lymphoma); cohort 3: R/R cutaneous T-cell lymphomas (CTCL; stage ≥1B; n = 11; 8 mycosis fungoides and 3 Sézary syndrome). Of all pts, 76.6% had advanced-stage disease, 51.9% had refractory disease, and 49.4% had ≥3 prior systemic regimens. Median treatment cycles for cohorts 1, 2, and 3 were 5 (range, 1-37), 4.5 (range, 1-38), and 17 (range, 3-25), respectively. Cohort 3 had promising efficacy (median follow-up [FU] 16.6 mo): ORR 45.5%; CR 9.1%; median DoR 11.3 mo (95% CI: 2.76-11.30); median PFS 16.8 mo; median OS not reached (NR). Modest efficacy was reported in cohort 1 (median FU 8.4 mo): ORR 31.8%; CR 18.2%; median DoR NR (95% CI: 2.66-not estimable [NE]); median PFS 2.7 mo; median OS 8.8 mo and also in cohort 2 (median FU 9.3 mo): ORR 20.5%; CR 9.1%; median DoR 8.2 mo (95% CI: 2.50-NE); median PFS 2.7 mo; median OS 13.3 mo. Most frequent adverse events (AEs) were pyrexia (32.5%), anemia (18.2%), arthralgia (18.2%), and diarrhea (15.6%); most frequent grade ≥3 AEs were anemia (7.8%), pneumonia (6.5%), and neutropenia (5.2%). Any grade immune-mediated AEs occurred in 22 (28.6%) pts, most frequently hypothyroidism (10.4%), hyperglycemia (5.2%), and rash (5.2%); and grade ≥3 in 4 (5.2%) pts (blood creatine phosphokinase increased, hepatitis, hypothyroidism, rash, and urticaria [1 pt each]). No treatment-related AEs led to death. Conclusions: TIS was well tolerated, achieving modest efficacy in R/R mature T/NK-cell neoplasms, with some long-lasting remissions particularly in CTCL. Further studies are warranted to determine the biologic features associated with response and explore optimal combination therapies. Clinical trial information: NCT03493451.

Late effects in survivors treated for lymphoma as adolescents and young adults: a population-based analysis

PURPOSE

The study objective is to describe and quantify the incidence of treatment-induced late effects in AYA lymphoma patients.

METHODS

Consecutive patients diagnosed with Hodgkin lymphoma (HL) or non-Hodgkin lymphoma (NHL) at 15-24 years of age were identified. All patients in British Columbia who received radiation therapy (RT) from 1974 to 2014 with ≥ 5-year survival post-RT were included. Late effects' analyses included only survivors who received RT to the relevant anatomical site(s) and/or relevant chemotherapy, and were reported as cumulative incidence (CI) ± standard error.

RESULTS

Three hundred and five patients were identified (74% HL). Median age of diagnosis was 21 years. Median follow-up was 19.1 years for secondary malignancy and 7.2 years for other endpoints. Hypothyroidism was the most prevalent late effect, with a CI of 22.4 ± 2.8% and 35.1 ± 4% at 5 and 10 years, respectively. CI of in-field secondary malignancy was 0.4 ± 0.4% at 10 years and 2.8 ± 1.2% at 20 years. CI of symptomatic pulmonary toxicity was 4.6 ± 1.5% and 6.8 ± 2.0% at 5 and 10 years, respectively, and was higher in patients receiving multiple RT courses (p = 0.009). Esophageal complications occurred at a CI of 1.4 ± 0.8% at 5 years and 2.2 ± 1.1% at 10 years. CI of xerostomia/dental decay was 2.6 ± 1.3% at 5 years and 4.9 ± 2.1% at 10 years. CI of cardiac disease was at 2.3 ± 0.9% at 5 years and 4.4 ± 1.5% at 10 years. CI of infertility was 6.5 ± 1.6% at 5 years and 9.4 ± 2.1% at 10 years.

CONCLUSION

Survivors of AYA lymphoma have a high incidence and diverse presentation of late effects.

IMPLICATIONS FOR CANCER SURVIVORS

AYA lymphoma survivors should be educated about their risks of late effects and offered screening and follow-up when appropriate.

Brentuximab vedotin with chemotherapy in adolescents and young adults (AYAs) with stage III or IV Hodgkin lymphoma: A subgroup analysis from the phase 3 Echelon-1 study

7528

Background: Hodgkin lymphoma (HL) is a rare disease that commonly occurs in adolescents and young adults (AYAs) which is typically defined as 15 to 39 years. Given their young age at presentation, key factors in treatment selection include a high cure rate and limiting long-term toxicities. Brentuximab vedotin (Adcetris®; A) is a CD30-directed ADC approved in combination with doxorubicin, vinblastine, and dacarbazine chemotherapy (A+AVD) for adults with previously untreated stage III/IV cHL based on results from the phase 3 ECHELON-1 trial. Recent 5-year data demonstrated a significantly improved PFS per investigator (INV) vs doxorubicin, bleomycin, vinblastine, and dacarbazine (ABVD) (HR, 0.69; 95% CI, 0.54–0.9; P = 0.003) (Straus 2020). Here we describe key efficacy and safety results for AYA pts enrolled in ECHELON-1. Methods: ECHELON-1 (N = 1334) is a global, open-label, multicenter, randomized trial of pts with previously untreated stage III/IV cHL. A total of 771 AYAs (57.8%) received either A+AVD (n = 396) or ABVD (n = 375) with a PET scan after cycle 2 (PET2). An analysis of PFS (time from randomization to progression or death from any cause) per INV was conducted. Results: After a median follow-up of 60.7 months (95% CI, 60.4-61.0), there was a 36% reduction in the risk of progression or death in AYAs receiving A+AVD vs ABVD (HR 0.64; 95% CI, 0.45-0.92; P = 0.013) with a 5-year PFS of 86.3% vs 79.4%, respectively, similar to the ITT population. The PFS benefit of A+AVD vs ABVD was independent of PET2 status; PET2 positivity (Deauville 4-5) was 6% and 8%, respectively. On the A+AVD arm, 81 AYAs (20%) had at least 1 subsequent anticancer therapy vs 96 AYAs (26%) on the ABVD arm; 26 AYAs (7%) received subsequent high dose chemotherapy and autologous stem cell transplant vs 32 AYAs (9%) on the A+AVD and ABVD arms, respectively. Resolution or improvement of peripheral neuropathy (PN) were similar in both arms; 224 AYAs (88%) on the A+AVD had resolution or improvement of PN vs 133 AYAs (89%) on the ABVD arm. Ongoing PN was predominantly Gr 1 (62%) and Gr 2 (26%), with 8 AYAs (13%) on the A+AVD arm and 1 AYA (5%) on the ABVD arm reporting ongoing Gr 3 PN. Finally, 7 AYAs (1.8%) and 5 AYAs (1.4%) on the A+AVD and ABVD arms, respectively, reported a secondary malignancy. Subsequent pregnancies were reported in female pts (44 A+AVD; 26 ABVD) and partners of male pts (31 A+AVD; 30 ABVD). No stillbirths were reported. All but 1 pt in each arm was < 40. Conclusions: Consistent with the ITT population, AYAs treated with A+AVD compared to ABVD had a durable PFS benefit at this significant 5-year milestone. No impact on the rate of secondary malignancies and a numerically greater number of pregnancies were observed, outcomes of interest to AYAs. Additionally, the majority of PN events improved or resolved over time. A+AVD should be considered a treatment option for AYAs with stage III/IV cHL. Clinical trial information: NCT01712490.

Comparison of Survivorship Care Guidelines for Patients With Lymphoma: Recommendations for Harmonization and Future Research Agenda

PURPOSE

Lymphomas are a heterogeneous group of diseases that develop in individuals of all ages and have variable prognoses. Improved survival resulting from therapy advances has led to the emergence of diverse late effects. Although several (US)-based organizations have developed survivorship guidelines, the distinct features of lymphoma subtypes and diverse therapies used raise concerns regarding their applicability to lymphoma survivors. We compared survivorship recommendations (outside primary disease monitoring) between US clinical guidelines.

METHODS

We extracted information from 17 guidelines from five US-based organizations: ASCO (n = 11), American Cancer Society (n = 1), Children's Oncology Group (n = 1), Center for International Blood and Marrow Transplant Research (n = 1), and the National Comprehensive Cancer Network (n = 3). Guidelines were evaluated to determine whether they offer recommendations on physical effects, psychosocial and quality of life (QOL), and health promotion and prevention. Comparisons were focused on second primary malignancy, cardiovascular complications, and vaccination.

RESULTS

Survivorship recommendations on physical effects and psychosocial and QOL mainly differ in the timing and approaches for screening. Vaccination recommendations were primarily derived from other cancer populations. Identified research gaps were a lack of understanding of the risk of late effects across lymphoma subtypes, the role of social determinants of health in survivorship, and the lack of a survivorship care model that integrates lymphoma subtypes and treatment exposures.

CONCLUSION

This study raises awareness about the complexity and challenges of managing survivors under the umbrella diagnosis of lymphoma. The inconsistency and incompleteness of existing guidelines may lead to suboptimal survivorship care. We propose expert-based research priorities to address gaps and unmet needs to help develop risk-based follow-up recommendations to optimize survivorship care for lymphoma survivors.

International Prognostic Score for Nodular Lymphocyte-Predominant Hodgkin Lymphoma

PURPOSE

Nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL) is a rare cancer, and large international cooperative efforts are needed to evaluate the significance of clinical risk factors and immunoarchitectural patterns (IAPs) for all stages of pediatric and adult patients with NLPHL.

METHODS

Thirty-eight institutions participated in the Global nLPHL One Working Group retrospective study of NLPHL cases from 1992 to 2021. We measured progression-free survival (PFS), overall survival (OS), transformation rate, and lymphoma-specific death rate. We performed uni- and multivariable (MVA) Cox regression stratified by management to select factors for the lymphocyte-predominant international prognostic score (LP-IPS) validated by five-fold cross-validation.

RESULTS

We identified 2,243 patients with a median age of 37 years (IQR, 23-51). The median follow-up was 6.3 years (IQR, 3.4-10.8). Most had stage I to II (72.9%) and few B symptoms (9.9%) or splenic involvement (5.4%). IAP was scored for 916 (40.8%). Frontline management included chemotherapy alone (32.4%), combined modality therapy (30.5%), radiotherapy alone (24.0%), observation after excision (4.6%), rituximab alone (4.0%), active surveillance (3.4%), and rituximab and radiotherapy (1.1%). The PFS, OS, transformation, and lymphoma-specific death rates at 10 years were 70.8%, 91.6%, 4.8%, and 3.3%, respectively. On MVA, IAPs were not associated with PFS or OS, but IAP E had higher risk of transformation (hazard ratio [HR], 1.81; P < .05). We developed the LP-IPS with 1 point each for age ≥45 years, stage III-IV, hemoglobin <10.5 g/dL, and splenic involvement. Increasing LP-IPS was significantly associated with worse PFS (HR, 1.52) and OS (HR, 2.31) and increased risk of lymphoma-specific death (HR, 2.63) and transformation (HR, 1.41).

CONCLUSION

In this comprehensive study of all ages of patients with NLPHL, we develop the LP-IPS to identify high-risk patients and inform upcoming prospective clinical trials evaluating de-escalation of therapy for patients with low LP-IPS scores (<2).

Abstract 2709: Evaluation of CD37 expression and binding of AGS67E, an antibody-drug conjugate (ADC) against CD37, on white blood cells (WBCs) collected from phase I non-Hodgkin lymphoma (NHL) patients

AGS67E is an antibody drug conjugate (ADC) against CD37 conjugated to monomethyl auristatin E (MMAE). CD37 is expressed on normal WBCs, but is also highly expressed in NHL, CLL and AML (Pereira et al., 2015). A phase I study is currently evaluating the safety, PK and anti-cancer activity of AGS67E with or without growth factor (GF) in subjects with relapsed/refractory NHL. To assess CD37 expression on WBCs, binding of AGS67E, and potential pharmacodynamic effects, samples from subjects were collected at pre-dose, D2, D8, and D15 and analyzed by flow cytometry. CD37 expression on subject tumor samples was also evaluated by immunohistochemistry (IHC). Our results demonstrated that CD37 was highly expressed in tumor samples and that AGS67E binds to WBCs causing down-regulation of CD37, achieving saturation of binding at 24 hours post-treatment (earliest time measured) at or above 0.9 mg/kg. A dose-dependent decrease in the number of all cell types examined was observed with a nadir occurring at D8, with partial or full recovery at D15, except for neutrophils. NK and T cell counts appeared to be least impacted while neutrophils were most affected. B cell counts were extremely low pre-dose for some patients, presumably from prior therapies. In patients treated at 0.9 mg/kg and higher without GF, recovery of neutrophils was delayed beyond D15. At doses of 1.2 mg/kg and higher, use of GF resulted in a significant recovery of neutrophils by D15. The extent of cell count decreases did not correlate to the proportion of cells expressing CD37. For example, decreases in NK cells, monocytes, and, in some cases, T cells, were much greater than the proportion of cells expressing CD37. Furthermore, mature WBCs are unlikely to be affected by AGS67E. This raises the possibility that the main effect of AGS67E may be on rapidly growing precursor cells and that cells with low, or no, CD37 expression may be impacted by the membrane permeable MMAE through a by-stander effect. The effect of AGS67E on neutrophils was investigated in an in vitro assay where hematopoietic stem cells were differentiated into neutrophils. Using this method, we showed that when AGS67C antibody was conjugated to a non-cleavable, membrane impermeable auristatin (mcMMAF) less cytotoxicity to differentiating neutrophils was observed compared to AGS67E. Previously, we have shown that neutrophils secrete proteases that can liberate MMAE from ADCs (Zhao et al, 2016). These results suggest that AGS67E contributes to neutropenia through a by-stander effect, in addition to the CD37-mediated internalization of the ADC. In conclusion, the results showed that AGS67E bound to its target CD37, modulated its expression, achieved saturation of binding at doses at or above 0.9 mg/kg, and reversibly depleted WBCs, with the exception of neutrophils for which GF administration appeared to significantly improve recovery rate.

Citation Format: Sher Karki, Hector Avina, Jacqueline Lackey, Ahmed Sawas, Kerry J. Savage, Raymond Perez, Ranjana Advani, Jasmine Zain, Owen A. O'Connor, Sara Gulesserian, Hui Zhao, Peng Yang, Karen Morrison, Leonard Reyno, Fernando Donate. Evaluation of CD37 expression and binding of AGS67E, an antibody-drug conjugate (ADC) against CD37, on white blood cells (WBCs) collected from phase I non-Hodgkin lymphoma (NHL) patients [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2709. doi:10.1158/1538-7445.AM2017-2709

Relapse timing is associated with distinct evolutionary dynamics in DLBCL

Diffuse large B-cell lymphoma (DLBCL) is cured in over 60% of patients, but outcomes are poor for patients with relapsed or refractory disease (rrDLBCL). Here, we performed whole genome/exome sequencing (WGS/WES) on tumors from 73 serially-biopsied patients with rrDLBCL. Based on the observation that outcomes to salvage therapy/autologous stem cell transplantation are related to time-to-relapse, we stratified patients into groups according to relapse timing to explore the relationship to genetic divergence and sensitivity to salvage immunochemotherapy. The degree of mutational divergence increased with time between biopsies, yet tumor pairs were mostly concordant for cell-of-origin, oncogene rearrangement status and genetics-based subgroup. In patients with highly divergent tumors, several genes acquired exclusive mutations independently in each tumor, which, along with concordance of genetics-based subgroups, suggests that the earliest mutations in a shared precursor cell constrain tumor evolution. These results suggest that late relapses commonly represent genetically distinct and chemotherapy-naïve disease.

Frontline Management of Nodal Peripheral T-Cell Lymphomas

Peripheral T-cell lymphomas (PTCLs) represent only 10%-15% of all non-Hodgkin lymphoma but encompass a diverse group of diseases with over 30 different subtypes. As a result of both disease heterogeneity and rarity, therapeutic progress of PTCLs has lagged behind B-cell lymphomas with very few randomized controlled studies to guide management. The most common subtypes are the so-called nodal PTCLs: PTCL-not otherwise specified (NOS), anaplastic large cell lymphoma (ALCL), and nodal T follicular helper cell lymphoma (TFHL) lymphoma, the latter of which includes angioimmunoblastic T-cell lymphoma. Anthracycline-based primary chemotherapy is still the mainstay of treatment for these common PTCL subtypes, but in recent years, we have moved into an era where more personalized therapy can be applied in some settings. Cyclophosphamide, doxorubicin, prednisone, and brentuximab vedotin CHP-BV is the first therapy in PTCL to show an overall survival benefit and represents a new standard for ALCL; however, there is less therapeutic certainty in other CD30-positive PTCLs. Recurrent mutations of epigenetic modifier genes typify TFHLs lymphomas, and collective studies demonstrate a heightened sensitivity to epigenetic therapies, leading to trials integrating these agents in the frontline setting. Molecular studies of PTCL-NOS have defined at least two subtypes, GATA3 and TBX21, the former having a poorer prognosis, but how this guides therapeutics remains unknown. Outside of ALCL, there is a growing debate as to whether trials should focus on adding a novel agent to cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) or whether combination novel therapies should be explored in the frontline therapy setting. Finally, the role of consolidative autologous stem-cell transplant in first remission remains an area of active debate.

Brentuximab vedotin plus cyclophosphamide, doxorubicin, etoposide, and prednisone followed by brentuximab vedotin consolidation in CD30-positive peripheral T-cell lymphomas: a multicentre, single-arm, phase 2 study

BACKGROUND

CD30 expression is universal in anaplastic large-cell lymphoma and is expressed in some other peripheral T-cell lymphoma subtypes. Incorporation of brentuximab vedotin into initial therapy for people with CD30-positive peripheral T-cell lymphomas prolonged progression-free survival, but there is room for improvement, especially for people with non-anaplastic large-cell lymphoma subtypes.

METHODS

We conducted a multicentre, international, single-arm, phase 2 trial to evaluate the safety and activity of CHEP-BV (cyclophosphamide, doxorubicin, prednisone, brentuximab vedotin, and etoposide) followed by brentuximab vedotin consolidation in patients with CD30-expressing peripheral T-cell lymphomas across five academic centres in the USA and Canada. Adults aged 18 years or older with newly diagnosed, untreated CD30-positive peripheral T-cell lymphomas, Eastern Cooperative Oncology Group score of 0-2, and adequate organ function were eligible to receive six planned cycles of CHEP-BV (ie, 1·8 mg/kg brentuximab vedotin intravenously on day 1, cyclophosphamide 750 mg/m2 intravenously on day 1, doxorubicin 50 mg/m2 intravenously on day 1, etoposide 100 mg/m2 daily intravenously on days 1-3, and prednisone 100 mg daily orally on days 1-5) with prophylactic G-CSF. Patients who responded to the treatment could receive brentuximab vedotin consolidation for up to ten additional cycles either after autologous haematopoietic stem-cell transplantation (HSCT) or directly after CHEP-BV. The primary endpoints were unacceptable toxicity during a 3-plus-3 safety lead-in in participants who received study treatment and completed the safety evaluation period (to confirm the recommended phase 2 dose of brentuximab vedotin in CHEP-BV) and the complete response rate after CHEP-BV induction therapy in participants who received study treatment and had response evaluation. The study was registered at ClinicalTrials.gov (NCT03113500), and this cohort completed the trial. The trial is ongoing with the enrolment of a new cohort.

FINDINGS

54 patients were screened for eligibility and 48 were eligible for the study. The participants (18 [38%] women and 30 [63%] men; 34 [71%] White, four [8%] Black, five [10%] Asian, ten [21%] Hispanic, and 37 [77%] non-Hispanic people) were recruited and enrolled between Dec 4, 2017, and June 14, 2021, and followed up until Aug 25, 2023, when the database was locked for analysis. 48 participants were evaluable for toxicity, and 47 were evaluable for response (one participant died from COVID-19 before response assessment). During the safety lead-in, one of six participants had an unacceptable toxicity (ie, platelet count <10 000 per mm3 in a participant with extensive bone marrow involvement), and the proposed phase 2 dose of 1·8 mg/kg brentuximab vedotin in CHEP-BV was confirmed. At completion of CHEP-BV, 37 of 47 participants had complete response, yielding a complete response rate of 79% (95% CI 64-89). The most common CHEP-BV-related toxicities of grade 3 or higher were neutropenia (14 [29%] of 48), leukopenia (11 [23%]), anaemia (ten [21%]), febrile neutropenia (ten [21%]), lymphopenia (nine [19%]), and thrombocytopenia (nine [19%]). There were no treatment-related deaths.

INTERPRETATION

In patients with mostly CD30-expressing peripheral T-cell lymphomas other than non-anaplastic large-cell lymphoma, CHEP-BV (with or without autologous HSCT) followed by brentuximab vedotin consolidation was safe and active.

FUNDING

SeaGen, Leukemia and Lymphoma Society, Lymphoma Research Foundation, and the National Cancer Institute of the National Institutes of Health.