Interim Positron Emission Tomography Research Articles

Interim PET-guided ABVD or ABVD/escalated BEACOPP for newly diagnosed advanced-stage classic Hodgkin lymphoma (JCOG1305).

This single-arm confirmatory study (JCOG1305) aimed to evaluate the utility of interim positron emission tomography (iPET)-guided therapy for newly diagnosed advanced-stage classic Hodgkin lymphoma (cHL). Patients aged 16-60 years with cHL received two cycles of doxorubicin, bleomycin, vinblastine, and dacarbazine (ABVD) and then underwent an iPET scan (PET2), which was centrally reviewed using a five-point Deauville scale. PET2-negative patients continued an additional four cycles of ABVD, whereas PET2-positive patients switched to six cycles of escalated bleomycin, etoposide, doxorubicin, cyclophosphamide, vincristine, procarbazine, and prednisone (eBEACOPP). The co-primary endpoints were 2-year progression-free survival (PFS) among all eligible and PET2-positive patients. Ninety-three patients were enrolled between January 2016 and December 2019. One patient was ineligible because of a diagnostic error. The median age of the 92 eligible patients was 35 (interquartile range, 28-48) years. Forty (43%) patients had stage III disease, and 43 (47%) had stage IV disease. The remaining nine (10%) patients had stage IIB disease with risk factors. Nineteen PET2-positive (21%) patients received eBEACOPP, 18 completed six cycles of eBEACOPP, 73 PET2-negative (79%) patients continued ABVD, and 70 completed an additional four cycles of ABVD. With a median follow-up period of 41.1 months, the 2-year PFS of 92 eligible patients and 19 PET2-positive patients were 84.8% (80% confidence interval [CI], 79.2-88.9) and 84.2% (80% CI, 69.7-92.1), respectively. Both primary endpoints were met at the prespecified threshold. This study demonstrates that iPET-guided therapy is a useful treatment option for younger patients with newly diagnosed advanced-stage cHL. Registration number: jRCTs031180218.

Real-life study on the use of response adapted therapy in patients with Hodgkin Lymphoma: Results from a multicenter experience.

Few data are known regarding the use of interim positron emission tomography (iPET) after the first two cycles (iPET2) of chemotherapy in treatment-naïve classical Hodgkin lymphoma (cHL) in routine clinical practice, and about the real-life adoption of intensification strategies for iPET positive patients. We conducted a multicenter retrospective study on cHL to investigate the use of iPET in the real-life setting, its prognostic role and outcomes of patients early shifted to intensification. Six hundreds and forty-one patients were enrolled (62% had advanced stage). iPET2 was positive in 89 patients (14%) including 8.7% and 17% early and advanced stage patients, respectively (p=0.003). Among iPET 2 positive cases treatment was immediately modified in 19 cases; in 14 cases treatment was modified after an additional positive iPET4. Overall 56 iPET2 positive patients never received intensified therapies. Most frequently used intensified therapy was autologous stem cell transplantation followed by BEACOPP. After a median follow-up of 72months, the 5-year progression-free survival (PFS) was 82% with iPET2 positive patients showing a worse PFS compared with iPET2 negative cases: 31% versus 85%. Focusing on advanced stage patients with a positive iPET2, the 5-year PFS was 59% for patients shifted to intensified therapy at any time point versus 61% for patients who never received intensified therapy. Our study confirmed the higher curability of naïve cHL patients in a real-world setting, and the prognostic role of iPET2 in this setting. A poor adherence to response-adapted strategy which however did not translate into a difference in patient outcomes.

Future perspectives of radiation therapy for Hodgkin Lymphoma: Risk-adapted, response-adapted, and safer than before.

Classical Hodgkin lymphoma is a lymphoproliferative disease with a good prognosis mainly seen in young people. Nevertheless secondary malignancy, cardiac disease and infertility may affect the long survivors with significant impact on quality of life, morbidity and overall survival. In the last decades several treatment strategies were evaluated to reduce the toxicity of first line treatment such as avoiding radiotherapy or its reduction in terms of dosage and extension. Many trials including interim Positron Emission Tomography evaluation fail to compare efficacy between combined modality treatment versus chemotherapy alone in particular in early stage disease. In this review we analyze which subset of patients could take advantage from proton therapy in terms of toxicity and cost effectiveness.

Primary gastric diffuse large B-cell lymphoma: A multicentre retrospective study.

Primary gastric diffuse large B-cell lymphoma (PG-DLBCL) accounts for the majority of extra-nodal DLBCL. Even so, literature is lacking on early, localised presentations. We studied a cohort of patients with stage I disease, diagnosed between 2006 and 2018, from six centres between Australia, Canada and Denmark. Our goal was to characterise outcomes, review treatmentand investigate the role of interim positron emission tomography (iPET). Thirty-seven eligible patients were identified. The median duration of follow-up was 42.2 months. All received chemoimmunotherapy with 91.9% (n = 34) given rituximab, cyclophosphamide, doxorubicin, vincristine and prednisolone (R-CHOP). 35.1% (n = 13) underwent consolidative radiotherapy. Eighteen patients were H. pylori positive and 11 had the documentation of H. pylori eradication therapy. The 4-year progression-free survival and overall survival of R-CHOP was 88% (95% CI: 71-95) and 91% (95% CI: 75-97) respectively. All patients who achieved a partial metabolic response or complete metabolic response on iPET went on to achieve complete response at the end of treatment. R-CHOP-based therapy with iPET assessment appears to offer favourable outcomes, with radiotherapy and H. pylori eradication therapy implemented on a case-by-case basis.

Involved-site Radiation Therapy is Equally Effective and Less Toxic Than Involved-field Radiation Therapy in Patients Receiving Combined Modality Treatment for Early-stage Unfavorable Hodgkin Lymphoma—An Analysis of the Randomized Phase 3 HD17 Trial of the German Hodgkin Study Group

PurposeCombined modality treatment (CMT) with chemotherapy followed by consolidation radiotherapy (RT), provides excellent outcomes for patients with early-stage Hodgkin lymphoma (HL). The international standard of care for consolidation RT, involved-site/involved-node radiotherapy (ISRT/INRT), has never been evaluated in a randomized phase III trial against the former standard involved-field radiotherapy (IFRT). Methods and materialsIn the multicenter phase III AnonymizedStudyGroupXXX AnonymizedStudyYYY trial, patients with early stage unfavorable HL were randomized between the standard CMT group and a positron-emission tomography (PET) -guided group. In the standard group, patients received two cycles of escalated bleomycin, etoposide, doxorubicin, cyclophosphamide, vincristine, procarbazine, and prednisone (eBEACOPP) and two cycles of doxorubicin, bleomycin, vinblastine, and dacarbazine (ABVD) followed by 30 Gray (Gy) IFRT. In the experimental group patients received no further therapy if post-chemotherapy PET was negative, and 30 Gy AnonymizedStudyGroupXXX -INRT, comparable and therefore termed here ISRT, if PET was positive. Here, we analyze the interim PET positive patients in a post hoc analysis, and therefore the randomized comparison of IFRT versus INRT/ISRT. Results1,100 patients were randomized, of which 311 had a positive PET after chemotherapy. Kaplan-Meier estimates of 4-year progression-free survival (PFS) were 96.8 % (95% CI: 91.6% – 98.8%) in the IFRT group and 95.4% (95% CI: 89.9% – 97.9%; HR: 1.40, 95% CI: 0.44 – 4.42) in the ISRT group. Pattern of recurrence analyses indicated that none of the cases of disease progression or recurrence in the ISRT group would have been prevented by the use of IFRT. Acute grade III/IV toxicities occurred in 8.5% of IFRT patients and 2.6% of ISRT patients (p=0.03). ConclusionsFor the first time, consolidation INRT/ISRT was randomly compared to IFRT in a phase III trial. Regarding PFS, no advantage for IFRT could be demonstrated. In summary, our data confirm the place of INRT/ISRT as the current standard of care.

PET4 Response As an Independent Predictor of Long-Term Outcomes in ECHELON2 (A+CHP Vs. CHOP) in CD30+PTCL

Background: Peripheral T-cell lymphomas (PTCLs) are uncommon, heterogeneous, and often aggressive subtypes of lymphoma characterized by a high risk of progression even after combination chemotherapy. The phase III, ECHELON-2 trial showed that the combination of brentuximab vedotin with chemotherapy (A+CHP) in patients (pts) with CD30-positive PTCLs improved progression-free survival (PFS) and overall survival (OS) compared to CHOP. In PTCL, positron emission tomography (PET) is a valuable way to assess disease burden and stage at the time of diagnosis and evaluate treatment response. Prior retrospective studies have shown that interim and end of treatment PET may predict outcomes; however, there are no prospective studies confirming their predictive value. In the ECHELON-2 study, PET4 outcomes were prospectively collected, and the objective of this exploratory analysis is to investigate the potential for interim PET scans to predict treatment response and long-term outcomes. Objective: To evaluate the role of interim 18F-FDG PET imaging (PET4) in predicting end of treatment (EOT) response, progression free survival (PFS), and overall survival (OS) in pts (pts) with CD30+PTCL treated with A+CHP or CHOP in the ECHELON-2 trial. Methods: The ECHELON-2 trial included prospective 18F-FDG PET scans and assessment of treatment response including long-term PFS per investigator and OS. PET4 status was based on Deauville score by Independent Review Facility (IRF) assessment using scans at the cycle 4 response assessment. Deauville scores 1-3 are considered negative (PET4neg) and 4-5 positive (PET4pos). EOT response is the best response after completion of study treatment and prior to long term follow up per Cheson 2007 by IRF assessment. Kaplan-Meier methods were used to estimate PFS and OS; p-values are based on stratified log-rank tests. All analyses are exploratory, and p-values are descriptive. Results: In this study, 452 pts were included, with 226 randomized to the A+CHP treatment arm and 226 to the CHOP treatment arm; median follow up was 66.8 months (range 0-90). Of randomized pts, 32 pts in the A+CHP arm and 41 pts in the CHOP arm were not evaluable for PET4. The overall results showed that the PET4neg evaluable subgroup had a higher proportion of pts achieving complete responses (CR) than PET4pos (80% vs. 9%) at EOT (Table 1). In pts assessed for PET4, pts who were PET4neg had improved PFS and OS in both the A+CHP and CHOP treatment arms (Figure 1). For A+CHP pts, those who achieved PET4neg had an improved PFS [HR 0.36, CI-95 (0.19-0.66), p=0.0006] and OS [HR 0.38, CI-95 (0.18-0.78), p=0.0060] compared to those who were PET4pos. Similarly, pts in the CHOP arm who achieved PET4neg had an improved PFS [HR 0.26, CI-95 (0.17-0.41), p<0.0001] and OS [HR 0.24, CI-95 (0.14-0.41), p< 0.0001] compared to those who were PET4pos. Among pts with anaplastic large cell lymphoma (sALCL) (n=316), 19 pts in the A+CHP arm and 32 in the CHOP arm were not evaluable for PET4. The results in this subgroup show that 128/143 (90%) A+CHP pts who had PET4 assessments achieved PET4neg. These pts experienced improved PFS [HR 0.28, CI-95 (0.14-0.60), p=0.0004] and OS [HR 0.38, CI-95 (0.16-0.94), p 0.0292] compared to PET4pos pts. For CHOP pts who had PET4 assessments 98/122 (80%), achieved PET4neg; these pts experienced improved PFS [HR 0.31, CI-95 (0.12-0.55), p<0.0001] and improved OS [HR 0.25, CI-95 (0.12-0.25), p= 0.0002] compared to PET4pos pts. Conclusion: In an exploratory analysis of interim PET imaging as part of the ECHELON-2 study, PET4neg by Deauville was associated with improved PFS and OS in both the A+CHP and CHOP arms. Our findings support the use of PET4 response in PTCL as a predictor of outcomes in both the A+CHP and CHOP pts. These findings emphasize the potential of PET scans to enhance risk stratification, individualize therapy decisions, and improve pt outcomes in the management of PTCLs. Further analysis will be presented at the meeting.

Investigating PET Responses to Treatment in Nodular Lymphocyte-Predominant Hodgkin Lymphoma.

There is no standard treatment for nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL). Although response by positron emission tomography (PET) for classic Hodgkin lymphoma (cHL) has allowed for response-adapted treatment, similar approaches for NLPHL have not been developed. This is in part due to the lack of data for PET response to treatment. Therefore, we sought to investigate PET responses to management for NLPHL. We retrospectively identified 47 patients who were diagnosed with or treated for NLPHL between 2001-2018 at a single institution and underwent a staging PET. We recorded clinical data and PET metrics for patients who received various forms of management, including chemotherapy (CT), radiation therapy (RT), combined modality therapy (CMT = CT+RT, with rituximab in a subset), rituximab monotherapy, and observation after excision. Metabolic response was scored according to the Deauville 5-point scale criteria, with complete metabolic response defined as a score 1-3. We identified 47 patients with median age of 26 (IQR = 17-50). They predominantly were male (74.5%) and had early stage (23.4% I, 36.2% II) versus advanced stage (29.8% III, 10.5% IV) NLPHL. The majority of patients had their immunoarchitectural pattern scored (n = 36, 76.6%), with typical pattern (A/B) being the most frequent type (58.3%). The median follow-up was 5.7 years (IQR = 2.3-9.3). Overall survival was 100% at 5 years and 92.3% at 10 years. Primary management included CMT (n = 10, 21.3%; with rituximab in a subset n = 1, 10.0%), CT alone (n = 22, 46.8%; with rituximab in a subset n = 5, 22.7%), RT alone (n = 8, 17.0%), rituximab alone (n = 3, 6.4%), and observation after excision (n = 4, 8.5%). On baseline PET, median SUVmax was 10.7 (range = 1.7-35.4). Of the 10 patients who received CMT, the complete metabolic response rates were 42.9% at interim-chemotherapy PET and 75% at post-chemotherapy PET, which improved to 100% after consolidative radiotherapy. There was no difference in complete metabolic response rate to chemotherapy for typical versus variant pattern (P = 0.60). Of the 22 patients who received CT alone, 66.7% had a complete metabolic response at the interim PET and 72.7% at the end of chemotherapy. For RT, rituximab alone, and observation, the complete metabolic response rates at median 3 months (range 1-5 months) after treatment were 87.5%, 66.7%, 75.0%, respectively. Based on our cohort, we found that patients with NLPHL had a lower complete metabolic response to CT (∼75%) compared to cHL (∼85-90%) and PET-response was improved following RT for those receiving CMT. There was no significant difference in PET-response for those with variant versus typical immunoarchitectural patterns. Our findings will allow for the development of PET response-adapted therapy for NLPHL.

Prognostic Significance of Positron Emission Tomography Delta Radiomics Following Bridging Therapy in Patients with Large B-Cell Lymphoma Undergoing CAR T-Cell Therapy

CAR T-cell therapy is routinely used as a treatment option for relapsed/refractory large B-cell lymphoma (LBCL). Bridging therapy radiation therapy (bRT) is increasingly being utilized prior to chimeric antigen receptor (CAR) T-cell therapy for large B-cell lymphoma (LBCL). It is unknown how the extent of debulking as a result of bRT impacts outcomes following CAR T-cell infusion. We hypothesized that the extent of debulking is prognostic of overall response to therapy. We reviewed patients with LBCL treated with bRT followed by commercially available CAR T-cell therapy between 2017 and 2022. Patients required a F-fluorodeoxyglucose (FDG) positron emission tomography (PET) scan prior to bRT and between completion of bRT and CAR T-cell infusion. On each scan, metabolic tumor volume (MTV), maximum standardized uptake value (SUVmax), SUVmean, and total lesion glycolysis (TLG) were determined. Delta-radiomics based on changes of these values between scans in patients overall and irradiated sites were then calculated. Optimal cut points were determined using maximally selected log-rank. The primary endpoints were progression-free survival (PFS) and local control (LC), measured from CAR T-cell infusion by Kaplan-Meier and Fine-Gray competing risk survival analyses, respectively. Twenty-three patients with LBCL with 33 irradiated sites were reviewed. All metabolically active disease was treated in 10 patients. Median equivalent dose in 2 Gy fractions (EQD2) was 26 Gy (14-44). Median interval from bRT to PET was 9 days (2-30). Following bRT, 2 patients achieved complete responses, 16 had partial responses, and 5 had progressive disease. Five irradiated sites progressed through bRT. No local failures were observed when EQD2>32.5 Gy was given. LC was improved with EQD2>20 Gy (24 mo LC: 94.5% vs 68.6%; p = 0.075). Following BRT, median overall decreases in MTV, SUVmax, SUVmean, and TLG were 22.2 cc (63.1%), 8.9 (36.8%), 3.4 (31.1%), and 297.9 cc (75.8%), respectively. Median decreases in MTV, SUVmax, SUVmean, and TLG in irradiated sites were 15.6 cc (91.1%), 17.0 (74.6%), 6.8 (55.3%), and 157.0 cc (94.6%), respectively. PFS was significantly improved in patients with reductions of MTV of at least 36 cc (24 mo PFS: 69.2% vs 0%; p = 0.047) or SUVmax of at least 15 (24-mo PFS: 80.0% vs 28.1%; p < 0.001). LC was significantly improved in lesions with reductions of SUVmax of at least 14 (24-mo LC: 100% vs 67.3%; p < 0.001) or SUVmean of at least 7 (24-mo LC: 100% vs 74.4%; p < 0.001). bRT led to significant reductions in MTV, SUVmax, SUVmean, and TLG. The extent of these decreases correlated with improved PFS and LC. There appears to be a dose-response relationship. Larger cohorts should validate the value of interim PET following bRT, and associated changes in disease burden as a means of prognosticating patients. Future work might evaluate whether escalation of BT in patients with suboptimal response, using either systemic therapy or higher radiation doses, has an impact on outcomes.

Management and Outcomes of Hodgkin Lymphoma Patients Who Achieve Partial Metabolic Response on PET Scans Post-Chemotherapy

Optimal management of patients with Hodgkin Lymphoma (HL) who do not achieve PET (positron emission tomography) complete metabolic response after primary systemic therapy is unclear. Options vary significantly and include radiation therapy (RT) to localized sites of PET avid disease, salvage chemotherapy followed by autologous stem-cell transplantation (ASCT), or observation with serial imaging. This multi-center study sought to investigate the management approaches and outcomes for HL patients who achieved partial metabolic response after primary systemic therapy. In this retrospective study, patients diagnosed with HL were identified from the electronic medical records database of two large academic centers between January 2009 and September 2021. PET scan results following initial chemotherapy were reviewed and responses were categorized using International Working Group (IWG) criteria, with the initial staging imaging being used as the reference against which response was evaluated. We performed descriptive analysis of demographic and clinical characteristics of the population and Kaplan-Meier estimates were used to determine progression-free survival (PFS). The charts of 1,093 HL patients were reviewed. A total of 765 patients had a post chemotherapy PET scan with 57 of those showing partial metabolic response. Among these 57 patients, 31 (54%) were male, the median age at diagnosis was 31 (range:18-74), and the median length of follow up was 1.6 years (average 2.9 years). Five percent stage I, 32% stage II, 23% stage III, and 40% stage IV. Typical initial chemotherapy included ABVD, ABVD switched to BEACOPP due to abnormal interim PET, and AVD with Brentuximab. Among all patients with metabolic partial response to chemotherapy, the 2-year PFS was 72.8% (95% CI = 60.9-87%). Thirty-three of these patients (58%) were treated with planned radiation therapy alone, and 2-year PFS was 80.7% (95% CI = 66.6-97.9%). For those who did not receive radiation as part of their treatment, progression rate was 38% at 2 years. To our knowledge, this is the largest series of HL patients with partial metabolic response following primary chemotherapy. Our preliminary analysis showed that treatment with radiation was associated with good PFS at 2 years and many of those treated with radiation alone were cured.

Consolidative Autotransplantation Achieves High Cure Rates in Adverse-Risk Large B Cell Lymphoma

There remains an unmet need to optimize the first-line treatment of patients with high-risk large B cell lymphoma (LBCL), particularly those with a high International Prognostic Index (IPI) score or a positive interim positron emission tomography (PET) scan who experience poor outcomes with R-CHOP. This study was conducted to evaluate the real-world effectiveness of consolidative autologous stem cell transplantation (ASCT) among patients with high-risk LBCL. This retrospective study included consecutive patients with LBCL and IPI score 4 or 5 who underwent consolidative ASCT as part of first-line therapy in Alberta, Canada. Progression-free survival (PFS), overall survival (OS), and disease-specific survival (DSS) were determined using the Kaplan-Meier method. The study cohort comprised 114 patients with median age of 60 years (range, 18 to 73 years), of whom 81 (71%) had an IPI score of 4 and 33 (29%) had an IPI score of 5. With a median follow-up of 5.6 years, the 5-year PFS was 72% (95% confidence interval [CI], 62% to 79%), 5-year OS was 74% (95% CI, 64% to 81%), and 5-year DSS was 80% (95% CI, 71% to 87%). There was no significant difference in PFS among patients with and patients without positive interim PET scans (n = 24), MYC and BCL2 and/or BCL6 rearrangements (n = 26), or central nervous system involvement (n = 15). Consolidative ASCT is associated with high cure rates and favorable survival outcomes in patients with high-risk LBCL and may overcome the adverse prognostic impact of a positive interim PET scan.

Cost-effectiveness of response-adapted therapy (RAT) for advanced Hodgkin’s Lymphoma compared with conventional treatment in India: a Markov-model based analysis

Cost effectiveness analysis of interim positron emission tomography (PET-2, done after 2 cycles of chemotherapy) based response adaptive therapy (RAT) approaches in advanced Hodgkin lymphoma (aHL) are not available from an Indian perspective. We used a five-year decision analytics model to assess the cost-effectiveness of the two RAT approaches [(escalation (RAT-1) or de-escalation (RAT-2)] compared with standard care (SOC) in aHL (mean age:35 years). Modelling data was derived from secondary sources and sensitivity analyses were performed to assess the robustness of the model. Net monetary benefit (NMB) gained from RAT2 in Indian rupees (INR) (INR 2,26,896) was higher than the RAT1 (INR 1,83,138) when compared with SOC. Proportion achieving the complete response after initial treatment (CR1) was the key determining factor for the RAT1/2 dominance over SOC. Despite higher initial input costs, response-adapted therapy of aHL was cost-effective by minimizing the cost incurred and disutility experienced during relapse and salvage.

Interim position emission tomography-computed tomography during multimodality treatment of locally advanced esophageal cancer: a scoping review.

Among cancers, esophageal cancer (EC) has one of the highest incidences and mortality in Asia. As recognized in many national guidelines, functional imaging performed with position emission tomography is recommended for patients with locally advanced disease. This review evaluated evidence for the use of fluorodeoxyglucose (FDG) interim positron emission tomography (PETint) in bimodality (chemoradiation) and trimodality (chemoradiation followed by surgery) management of locally advanced esophageal cancer (LAEC), with a focus on its prognostic and predictive value. The MEDLINE database was searched from January 1, 2001, to January 1, 2022, as part of a scoping review. References of selected articles were manually checked to identify other articles meeting the inclusion criteria; only original articles were included, and reviews, guidelines, letters, editorials, and case reports were excluded. A total of 63 articles were included in this review. PET-computed tomography (PET-CT) is recognized as having a significant role in the assessment of treatment response. Studies on the predictive PETint suggest that it has a certain value, particularly for early response. Identification of poor responders or nonresponders soon after commencement of multimodality treatment allows for treatment modification. The scoping review indicated variable utility for the prognostic value of PETint. There is a need to improve its accuracy, which can likely be achieved through greater standardization of measurements and reporting and testing as well as combination with other promising measures of response to residual disease.

POSTER: HL-007 The Role of Interim Positron Emission Tomography (PET)/Computed Tomography (CT) Scans in the Management of Hodgkin Lymphoma: A Single-Center Study in a Developing Country

POSTER: HL-007 The Role of Interim Positron Emission Tomography (PET)/Computed Tomography (CT) Scans in the Management of Hodgkin Lymphoma: A Single-Center Study in a Developing Country

HL-007 The Role of Interim Positron Emission Tomography (PET)/Computed Tomography (CT) Scans in the Management of Hodgkin Lymphoma: A Single-Center Study in a Developing Country

HL-007 The Role of Interim Positron Emission Tomography (PET)/Computed Tomography (CT) Scans in the Management of Hodgkin Lymphoma: A Single-Center Study in a Developing Country

Outcome prediction by interim positron emission tomography and IgM monoclonal gammopathy in diffuse large B-cell lymphoma.

In diffuse large B-cell lymphoma (DLBCL), a positive interim positron emission tomography (PET) scan predicts treatment failure, but the proportion of high-risk patients thus identified is small. To improve prediction, we combined the interim PET result with the presence or absence of an associated IgM gammopathy. Of 108 DLBCL patients participating in a prospective trial, nine (8%) were interim PET positive and 19 (18%) had an IgM gammopathy. The monoclonal protein was not associated with distinguishing genetic features, and its light chain restriction was not always concordant with the light chain restriction of the lymphoma. The information provided by interim PET and IgM gammopathy was combined to dichotomize the population into sizeable high-risk (1-2 adverse factors) and low-risk groups (no adverse factor) with widely different outcomes (population size, 25% vs. 75%; 3-year risk of progression, 51% vs. 10%; 3-year overall survival, 64% vs. 95%). Multivariable analyses including established risk factors revealed the interim PET result and the IgM gammopathy status to be the only factors significantly associated with outcome. Information about interim PET response and IgM gammopathy may be useful in studies testing risk-adapted treatment strategies.

Positron emission tomography-adapted therapy in low-risk diffuse large B-cell lymphoma: results of a randomized, phase III, non-inferiority trial.

The current standard of care for non-bulky diffuse large B-cell lymphoma (DLBCL) patients with an International Prognostic Index (IPI) of 0 is four cycles of rituximab plus cyclophosphamide, doxorubicin, vincristine and prednisone (R-CHOP) but whether the same efficacy can be achieved with reduced chemotherapy regimen of four cycles for non-bulky DLBCL patients with an IPI of 1 remains unclear. This study compared four cycles versus six cycles of chemotherapy in non-bulky low-risk DLBCL patients with negative interim positron emission tomography with computed tomography (PET-CT, Deauville 1-3), irrespective of age and other IPI risk factors (IPI 0-1). This was an open-label, randomized, phase III, non-inferiority trial. Patients aged 14-75 years with newly diagnosed low-risk DLBCL, according to IPI, achieving PET-CT confirmed complete response (CR) after four cycles of R-CHOP were randomized (1:1) between four cycles of rituximab (4R-CHOP+4R arm) or two cycles of R-CHOP plus two cycles of rituximab (6R-CHOP+2R arm). The primary endpoint was 2-year progression-free survival (PFS), conducted in the intention-to-treat population. Safety was assessed in patients with at least one cycle of assigned treatment. The non-inferiority margin was -8%. A total of 287 patients were included in the intention-to-treat analysis, the median follow-up was 47.3 months, and the 2-year PFS rate was 95% (95% confidence interval [CI], 92% to 99%) and 94% (95% CI, 91% to 98%) for the 4R-CHOP+4R and 6R-CHOP+2R arm. The absolute difference in 2-year PFS between the two arms was 1% (95% CI, -5% to 7%), supporting the non-inferiority of 4R-CHOP+4R. Grade 3-4 neutropenia was lower in the last four cycles of rituximab alone in the 4R-CHOP+4R arm (16.7% versus 76.9%), with decreased risk of febrile neutropenia (0.0% versus 8.4%) and infection (2.1% versus 14.0%). For newly diagnosed low-risk DLBCL patients, interim PET-CT after four cycles of R-CHOP was effective in identifying patients with Deauville 1-3 who would have a good response and Deauville 4-5 patients who might have high-risk biological features or develop resistance. Reducing the standard six cycles to four cycles of chemotherapy had comparable clinical efficacy and fewer adverse events in low-risk, non-bulky DLBCL with interim PET-CT confirmed CR.

Interim PET-guided treatment for early-stage NLPHL: a subgroup analysis of the randomized GHSG HD16 and HD17 studies

AbstractThe optimal first-line treatment for nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL) diagnosed in early stages is largely undefined. We, therefore, analyzed 100 NLPHL patients treated in the randomized HD16 (early-stage favorable; n = 85) and HD17 (early-stage unfavorable; n = 15) studies. These studies investigated the omission of consolidation radiotherapy (RT) in patients with a negative interim positron emission tomography (iPET) (ie, Deauville score <3) after chemotherapy (HD16: 2× doxorubicin, bleomycin, vinblastine, and dacarbazine [ABVD]; HD17: 2× escalated bleomycin, etoposide, doxorubicin, cyclophosphamide, vincristine, procarbazine, and prednisone [BEACOPP] plus 2× ABVD). Patients with NLPHL treated in the HD16 and HD17 studies had 5-year progression-free survival (PFS) rates of 90.3% and 92.9%, respectively. Thus, the 5-year PFS did not differ significantly from that of patients with classical Hodgkin lymphoma treated within the same studies (HD16: P = .88; HD17: P = .50). Patients with early-stage favorable NLPHL who had a negative iPET after 2× ABVD and did not undergo consolidation RT tended to have a worse 5-year PFS than patients with a negative iPET who received consolidation RT (83% vs 100%; P = .05). There were 10 cases of NLPHL recurrence. However, no NLPHL patient died during follow-up. Hence, the 5-year overall survival rate was 100%. Taken together, contemporary Hodgkin lymphoma-directed treatment approaches result in excellent outcomes for patients with newly diagnosed early-stage NLPHL and, thus, represent valid treatment options. In early-stage favorable NLPHL, consolidation RT appears necessary after 2× ABVD to achieve the optimal disease control irrespective of the iPET result.

Results of R-CHOP and R-CHOP + interleukin-2 regimens in first-line therapy in patients with diffuse B-cell lymphoma

The study was made to evaluate the effect of interleukin-2 (IL-2) as part of the R-CHOP regimen on the rate of a complete metabolic response (CMR) using the data of interim positron emission tomography (PET/CT) and progression-free survival compared to the standard regimen in patients with diffuse B-cell lymphoma (DCLC). The data of 152 patients with biopsy-proven DCLC who were treated in the period 2015–2020 were included. Among them, 59 patients were included in the prospective group (R-CHOP + IL-2 in a total course dose of 5,000,000 IU). The control group consisting of 93 patients received standard R-CHOP therapy. PET/CT was performed after 4 courses of therapy, metabolic response was assessed using the Deauville scale, and Deauville 1-2 was classified as CMR. The rate of CMR in the R-CHOP+IL-2 group was 67.8 %, while in the control group it was 50.5 % (pχ² = 0.044). The 5-year progression-free survival (PFS) in the R-CHOP+IL-2 and R-CHOP groups was 80.7 and 64.5 %, respectively (p = 0.04). In the favorable and intermediate prognosis groups (IPI 0–3), PFS was not statistically significantly different depending on treatment. At high risk (IPI 4–5), the 5-year PFS in the R-CHOP + IL-2 and R-CHOP groups was 71.4 and 25.0 %, respectively (p = 0.02). Including IL-2 in the R-CHOP regimen in the first-line treatment of patients with DCLC increases the incidence of CMR according to 18-FDG PET/CT after 4 courses of chemoimmunotherapy and PFS in the high-risk group.

Brentuximab vedotin plus doxorubicin and dacarbazine innonbulky limited-stage classical Hodgkin lymphoma.

ABVD (Adriamycin, bleomycin, vinblastine, dacarbazine) with or without radiation has been the standard treatment for limited-stage Hodgkin lymphoma (HL) but carries risks of bleomycin lung injury and radiation toxicity. Brentuximab vedotin (BV) is approved with AVD for stage III-IV HL, but carries increased risks of peripheral neuropathy (PN) and neutropenic fever, likely due to overlapping toxicity between BV and vinblastine. We therefore evaluated BV in combination with AD for 4 or 6 cycles based on interim positron emission tomography response. Thirty-four patients with nonbulky stage I-II HL were enrolled. Risk was early favorable in 53% and unfavorable in 47%. The overall and complete response rates (CRRs) were 100% and 97%, respectively, with a 5-year progression-free survival (PFS) of 91%. No differences in outcome were observed based on stage (I vs II) or risk status (early favorable vs unfavorable). The most common adverse events were nausea (85%), peripheral sensory neuropathy (59%), and fatigue (56%). There were no cases of grade-4 neutropenia or neutropenic fever, and no patient received granulocyte-colony stimulating factor. Most cases of PN were grade 1, and no patient experienced grade ≥3 PN. BV-AD produced a high CRR and durable PFS with most patients requiring 4 cycles of therapy. Compared with BV-AVD, the toxicity profile appeared improved, with predominantly grade 1 reversible PN and no case of grade 4 neutropenia or neutropenic fever. This regimen warrants further study in HL and may serve as a backbone for the addition of novel agents. This trial is registered on clinicaltrials.gov (NCT02505269).

Outcomes of Patients with Positive Interim Positron Emission Tomography (PET) Continuing ABVD in the Clinical Setting

Recent prospective clinical trial data suggest that patients with Hodgkin's lymphoma who continue treatment with ABVD, despite failing to attain a complete metabolic response on interim PET (PET2+), may fare better than previously published. We describe the outcomes of PET2+ patients who continued ABVD and compare the performance of a quantitative measure based on the lesion-to-liver SUV ratio (LLS qPET2+) to that of the subjective Deauville criteria (dvPET2+). We analyzed all patients with newly diagnosed advanced-stage Hodgkin lymphoma treated with frontline ABVD at the Memorial Sloan Kettering Cancer Center between 2008 and 2017. Eligibility was set to correspond with the RATHL inclusion criteria. Images were reviewed by two nuclear medicine physicians and discordant cases were resolved with a third expert in consensus. qPET2+ was defined as LLS ≥ 1.3. We identified 227 patients of whom 25% (57) were qPET2+, but only 14% (31) were dvPET2+. Forty-eight patients (84%) continued ABVD with a 3-year PFS of 70% for qPET2+ and 64% for dvPET2+. In conclusion, interim PET interpretation in clinical practice may be associated with a higher rate of scans deemed positive. Irrespective of the criteria for PET2 positivity, a subset of patients may continue ABVD without a dismal outcome.