Diffuse large B-cell lymphoma involving osseous sites: utility of response assessment by PET/CT and good longterm outcomes.

Osseous involvement by diffuse large B-cell lymphoma (DLBCL-bone) is a heterogeneous disease. There is limited data regarding response assessment by positron emission tomography with fluorodeoxyglucose, which may demonstrate residual avidity despite a complete response. We analyzed clinical data of patients with newly diagnosed DLBCL and identified all cases with DLBCL-bone. End of treatment scans were reviewed by two independent experts classifying osseous lesions into Deauville (DV) ≤3; DV ≥4, or reactive uptake in the bone marrow (M), site of fracture (F) or surgery (S). We compared outcomes of DLBCL-bone to other extranodal sites (EN) matched on International Prognotic Index features and regimen. Of 1,860 patients with DLBCL (bone 16%; EN 45%; nodal 39%), 41% had localized disease and 59% advanced. Only 9% (n=27) of patients with initial bone involvement had residual fluorodeoxyglucose avidity at the osseous site. In half of these cases, the uptake was attributed to F/S/M, and of the remaining 13, only two were truly refractory (both with persistent disease at other sites). Overall survival and progression-free survival (PFS) were found to be similar for early- stage nodal DLBCL and DLBCL-bone, but inferior in EN-DLBCL. Advanced-stage disease involving the bone had a similar 5-year PFS to nodal disease and EN-DLBCL. After matching for International Prognotic Index and treatment regiments, PFS between bone and other EN sites was similar. Osseous involvement in DLBCL does not portend a worse prognosis. End of treatment DV ≥4 can be expected in 5-10% of cases, but in the absence of other signs of refractory disease, may be followed expectantly.

Clinical characteristics and outcomes of extranodal stage I diffuse large B-cell lymphoma in the rituximab era.

This retrospective study aimed to better define the characteristics and outcomes of extranodal stage I diffuse large B-cell lymphoma (DLBCL) in the rituximab era. Patients diagnosed with stage I DLBCL from 2001 to 2015 treated with rituximab, cyclophosphamide, doxorubicin, vincristine, prednisone (R-CHOP) or R-CHOP-like regimens with or without radiation (RT) were included. We identified 1955 patients with newly diagnosed DLBCL, of whom 341 had stage I and were eligible for this analysis. Extranodal presentation was observed in 224 (66%) patients, whereas 117 (34%) had nodal involvement. The most common extranodal sites were as follows: bone, 21%; stomach, 19%; testis, 9%; intestine, 8%; breast, 8%. Overall, 69% extranodal patients and 68% nodal patients received RT. Median follow-up was 5.5 years (interquartile range, 4.3-8.2). Ten-year overall survival (OS) and disease-free survival were 77% (95% confidence interval [CI], 67%-83%) and 77% (95% CI, 68%-85%). In the multivariable analyses, extranodal involvement was associated with worse OS (hazard ratio [HR], 3.44; 95% CI, 1.05-11.30) and progression-free survival (PFS; HR, 3.25; 95% CI, 1.08-9.72) compared with nodal involvement. Consolidation RT was associated with better OS (HR, 0.26; 95% CI, 0.12-0.49) and PFS (HR, 0.35; 95% CI, 0.18-0.69) in the extranodal population; however, the benefit was no longer observed in patients that were positron emission tomography (PET) negative at the end of immunochemotherapy. Relapses occurred usually late (median, 37 months), and the most common sites were the lymph nodes (31%) and the central nervous system (27%). Extranodal stage I DLBCL had a worse outcome than nodal stage 1 DLBCL. End of immunochemotherapy PET results may help select extranodal patients for consolidation RT.

Assessment of Lymphoma and Other Hematologic Malignancies Training Needs Among Radiation Oncology Residents: a Brief Report.

The role of radiation therapy (RT) varies across hematologic malignancies (HM). Radiation oncology (RO) resident comfort with specific aspects of HM patient management is unknown. The International Lymphoma RO Group (ILROG) assessed resident HM training opportunities and interest in an HM away elective. RO residents (PGY2-5) in the Association of Residents in RO (ARRO) database (n = 572) were emailed an anonymous, web-based survey in January 2019 including binary, Likert-type scale (1 = not at all, 5 = extremely, reported as median [interquartile range]), and multiple-choice questions. Of 134 resident respondents (23%), 86 (64%) were PGY4/5 residents and 36 (27%) were in larger programs (≥ 13 residents). Residents reported having specialized HM faculty (112, 84%) and a dedicated HM rotation (95, 71%). Residents reported "moderate" preparedness to advocate for RT in multidisciplinary conferences (3 [2-3]); make HM-related clinical decisions (3 [2-4]); and critique treatment planning (3 [2-4]). They reported feeling "moderately" to "quite" prepared to contour HM cases (3.5 [3-4]) and "quite" prepared to utilize the PET-CT five-point scale (4 [3-5]). Overall, residents reported feeling "moderately" prepared to treat HM patients (3 [2-3]); 24 residents (23%) felt "quite" or "extremely" prepared. Sixty-six residents (49%) were potentially interested in an HM away elective, commonly to increase comfort with treating HM patients (65%). Therefore, HM training is an important component of RO residency, yet a minority of surveyed trainees felt quite or extremely well prepared to treat HM patients. Programs should explore alternative and additional educational opportunities to increase resident comfort with treating HM patients.

ILROG emergency guidelines for radiation therapy of hematological malignancies during the COVID-19 pandemic.

The International Lymphoma Radiation Oncology Group (ILROG) guidelines for using radiation therapy (RT) in hematological malignancies are widely used in many countries. The emergency situation created by the COVID-19 pandemic may result in limitations of treatment resources. Furthermore, in recognition of the need to also reduce the exposure of patients and staff to potential infection with COVID-19, the ILROG task force has made recommendations for alternative radiation treatment schemes. The emphasis is on maintaining clinical efficacy and safety by increasing the dose per fraction while reducing the number of daily treatments. The guidance is informed by adhering to acceptable radiobiological parameters and clinical tolerability. The options for delaying or omitting RT in some hematological categories are also discussed.

NCCN Guidelines® Insights: Hodgkin Lymphoma, Version 2.2022.

Hodgkin lymphoma (HL) is an uncommon malignancy of B-cell origin. Classical HL (cHL) and nodular lymphocyte-predominant HL are the 2 main types of HL. The cure rates for HL have increased so markedly with the advent of modern treatment options that overriding treatment considerations often relate to long-term toxicity. These NCCN Guidelines Insights discuss the recent updates to the NCCN Guidelines for HL focusing on (1) radiation therapy dose constraints in the management of patients with HL, and (2) the management of advanced-stage and relapsed or refractory cHL.

Definitive radiotherapy for localized follicular lymphoma staged by 18F-FDG PET-CT: a collaborative study by ILROG.

Radiotherapy (RT) can be curative in patients with localized follicular lymphoma (FL), with historical series showing a 10-year disease-free survival of 40 to 50%. As 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography with computerized tomography (PET-CT) upstages 10 to 60% of patients compared to CT, we sought to evaluate outcomes in patients staged by PET-CT, to determine if more accurate staging leads to better patient selection and results. We conducted a multicenter retrospective study under the direction of the International Lymphoma Radiation Oncology Group (ILROG). Inclusion criteria were: RT alone for untreated stage I to II FL (grade 1-3A) with dose equivalent ≥24 Gy, staged by PET-CT, age ≥18 years, and follow-up ≥3 months. End points were freedom from progression (FFP), local control, and overall survival (OS). A total of 512 patients treated between 2000 and 2017 at 16 centers were eligible for analysis; median age was 58 years (range, 20-90); 410 patients (80.1%) had stage I disease; median RT dose was 30 Gy (24-52); and median follow-up was 52 months (3.2-174.6). Five-year FFP and OS were 68.9% and 95.7%. For stage I, FFP was 74.1% vs 49.1% for stage II (P < .0001). Eight patients relapsed in-field (1.6%). Four had marginal recurrences (0.8%) resulting in local control rate of 97.6%. On multivariable analysis, stage II (hazard ratio [HR], 2.11; 95% confidence interval [CI], 1.44-3.10) and BCL2 expression (HR, 1.62; 95% CI, 1.07-2.47) were significantly associated with less favorable FFP. Outcome after RT in PET-CT staged patients appears to be better than in earlier series, particularly in stage I disease, suggesting that the curative potential of RT for truly localized FL has been underestimated.

Low grade, indolent lymphomas of the head and neck: Comparative toxicity of standard versus very low dose radiation therapy.

National Comprehensive Cancer Network guidelines recommend radiation therapy (RT) for localized indolent non-Hodgkin lymphomas (iNHL). Many referring physicians avoid RT to the head and neck (HN) due to fears of toxicity. Very low-dose radiation (4 Gy) for select patients produces sustained local control and recently gained popularity. We compared early and late toxicities of standard 24-30 Gy to 4 Gy in patients with HN iNHL. We retrospectively analyzed 266 consecutive patients with HN iNHL receiving RT from 1994 to 2017. Patient characteristics, outcomes, and toxicities were collected from medical records. Early (≤2 months post-RT) and late (>2 months post-RT) toxicities were graded per Common Terminology Criteria for Adverse Events version 4. Grades 1-2 were defined as "low-grade" and 3-4 "high-grade." Toxicity incidence was compared between 4 and >4 Gy, grouped by treated site (orbit, nonorbital head, neck, skin) and early versus late. Median follow-up was 23 months (2-145) and 68 months (2-256) for 4Gy and >4 Gy cohorts, respectively. Median dose for the >4 Gy cohort was 30 Gy (10.5-54 Gy). Early and late toxicity incidences were lower in the 4 Gy cohort compared to >4 Gy across all RT-sites: early toxicity, orbit, 42% versus 96%; nonorbital head, 24% versus 96%; neck, 22% versus 94%; skin, 31% versus 87%; late toxicity, orbit, 20% versus 71%; nonorbital head, 6% versus 66%; neck, 6% versus 57%; skin, 0% versus 46% (4 Gy vs. >4 Gy, respectively). Toxicities among both cohorts were largely low-grade. High-grade early and late toxicities did not occur in the 4 Gy cohort. There was 1 high-grade early toxicity (Grade 3 dry mouth) and 17 high-grade late toxicities (Grade 3 cataracts) in the >4 Gy cohort. RT to HN for iNHL is associated with minimal short- and long-term toxicity and excellent local control among 4 Gy and >4 Gy treatments. In this setting, "toxicity" concerns should not deter oncologists from potentially curative RT. In select patients where toxicity remains a concern, very low dose 4 Gy could be considered.

Early experience using salvage radiotherapy for relapsed/refractory non-Hodgkin lymphomas after CD19 chimeric antigen receptor (CAR) T cell therapy.

Radiotherapy is potentially an important salvage strategy post-chimeric antigen receptor T cell therapy (CART), but limited data exist. We reviewed 14 patients treated with salvage radiation post-CART progression (SRT). Most received SRT for first post-CART relapse (71%) to sites previously PET-avid pre-CART (79%). Median overall survival (OS) post-SRT was 10 months. Post-SRT, six localized relapses achieved 100% response (3 = complete, 3 = partial), with improved freedom from subsequent relapse (P = 0·001) and OS (P = 0·004) compared to advanced stage relapses. Three were bridged to allogeneic transplantation; at analysis, all were alive/NED. SRT has diverse utility and can integrate with novel agents or transplantation to attempt durable remissions.

Proton therapy for adults with mediastinal lymphomas: the International Lymphoma Radiation Oncology Group guidelines.

Among adult lymphoma survivors, radiation treatment techniques that increase the excess radiation dose to organs at risk (OARs) put patients at risk for increased side effects, especially late toxicities. Minimizing radiation to OARs in adults patients with Hodgkin and non-Hodgkin lymphomas involving the mediastinum is the deciding factor for the choice of treatment modality. Proton therapy may help to reduce the radiation dose to the OARs and reduce toxicities, especially the risks for cardiac morbidity and second cancers. Because proton therapy may have some disadvantages, identifying the patients and the circumstances that may benefit the most from proton therapy is important. We present modern guidelines to identify adult lymphoma patients who may derive the greatest benefit from proton therapy, along with an analysis of the advantages and disadvantages of proton treatment.

Hodgkin Lymphoma, Version 2.2020, NCCN Clinical Practice Guidelines in Oncology.

The NCCN Clinical Practice Guidelines in Oncology for Hodgkin Lymphoma (HL) provide recommendations for the management of adult patients with HL. The NCCN panel meets at least annually to review comments from reviewers within their institutions, examine relevant data, and reevaluate and update their recommendations. Current management of classic HL involves initial treatment with chemotherapy alone or combined modality therapy followed by restaging with PET/CT to assess treatment response. Overall, the introduction of less toxic and more effective regimens has significantly advanced HL cure rates. This portion of the NCCN Guidelines focuses on the management of classic HL.

Diagnostic and Therapeutic Considerations for Extramedullary Leukemia.

PURPOSE OF REVIEW: The purpose of this review is to summarize the current literature on the presentation, diagnosis, and treatment options available for extramedullary (EM) manifestations of leukemia including myeloid sarcoma (MS) and leukemia cutis (LC). RECENT FINDINGS: Advanced imaging using 18FDG-PET/CT is an effective screening tool for EM manifestations of leukemia. The role of radiation therapy has been more clearly delineated in the treatment of both MS and LC. FDA-approved targeted agents have improved outcomes in patients with AML but have not demonstrated improvements specifically for EM; however, a checkpoint inhibitor, Ipilimumab, holds promise in impacting local control for the treatment of AML-related EM. EM manifestations of leukemia pose significant therapeutic challenges. Treatment of EM is predicated on multiple factors including the presence of concomitant bone marrow involvement, AML-risk classification, and timing of presentation at initial diagnosis or relapse following systemic therapy.

Prognostic significance of baseline metabolic tumor volume in relapsed and refractory Hodgkin lymphoma.

Identification of prognostic factors for patients with relapsed/refractory Hodgkin lymphoma (HL) is essential for optimizing therapy with risk-adapted approaches. In our phase 2 study of positron emission tomography (PET)-adapted salvage therapy with brentuximab vedotin (BV) and augmented ifosfamide, carboplatin, and etoposide (augICE), we assessed clinical factors, quantitative PET assessments, and cytokine and chemokine values. Transplant-eligible patients with relapsed/refractory HL received 2 (cohort 1) or 3 (cohort 2) cycles of weekly BV; PET-negative patients (Deauville score ≤2) proceeded to autologous stem cell transplantation (ASCT) whereas PET-positive patients received augICE before ASCT. Serum cytokine and chemokine levels were measured at baseline and after BV. Metabolic tumor volume (MTV) and total lesion glycolysis were measured at baseline, after BV, and after augICE. Sixty-five patients enrolled (45, cohort 1; 20, cohort 2); 49 (75%) achieved complete response and 64 proceeded to ASCT. Three-year overall survival and event-free survival (EFS) were 95% and 82%, respectively. Factors predictive for EFS by multivariable analysis were baseline MTV (bMTV) (P < .001) and refractory disease (P = .003). Low bMTV (<109.5 cm3) and relapsed disease identified a favorable group (3-year EFS, 100%). For patients who received a transplant, bMTV and pre-ASCT PET were independently prognostic; 3-year EFS for pre-ASCT PET-positive patients with low bMTV was 86%. In this phase 2 study of PET-adapted therapy with BV and augICE for relapsed/refractory HL, bMTV and refractory disease were independent prognostic factors for EFS. Furthermore, bMTV improved the predictive power of pre-ASCT PET. Future studies should optimize efficacy and tolerability of salvage therapy by stratifying patients according to risk factors such as bMTV.

Longitudinal cognitive assessment in patients with primary CNS lymphoma treated with induction chemotherapy followed by reduced-dose whole-brain radiotherapy or autologous stem cell transplantation.

INTRODUCTION: The standard treatment for primary central nervous system lymphoma (PCNSL) involves induction methotrexate-based chemotherapy with or without consolidation whole brain radiotherapy (WBRT). As WBRT carries a substantial risk for cognitive impairment, alternative consolidation treatments have been used to reduce neurotoxicity, including reduced-dose WBRT (rdWBRT) or high-dose chemotherapy with autologous stem cell transplant (HDC-ASCT). In this study, we characterized cognitive functions in PCNSL patients achieving long-term remission following rdWBRT or HDC-ASCT. METHODS: PCNSL patients completed cognitive evaluations at diagnosis, post-induction chemotherapy, and yearly up to 5 years following rdWBRT or HDC-ASCT. Quality of life (QoL), white matter (WM) disease, and cortical atrophy (CA) on MRI were assessed at similar intervals. RESULTS: Performance was impaired on most cognitive tests at diagnosis. Linear mixed model analyses in each group showed statistically significant improvement from baseline up to year 3 in attention/executive functions, graphomotor speed, and memory; however, there was a decline in attention/executive functions and memory after year 3 in both groups. WM abnormalities increased over time in both groups, but more patients treated with rdWBRT developed CA and WM changes. There were no significant longitudinal group differences in cognitive performance or QoL. CONCLUSIONS: Results indicated improvement in cognitive function up to 3 years post-treatment, but a decline at later time points and an increase in brain structure abnormalities in both groups. The findings suggest that rdWBRT and HDC-ASCT may be associated with delayed neurotoxicity in progression-free patients and underscore the need for long-term follow-up to characterize cognitive dysfunction in PCNSL patients.

Low-Dose Radiation Conditioning Enables CAR T Cells to Mitigate Antigen Escape.

CD19 chimeric antigen receptors (CARs) have demonstrated great efficacy against a range of B cell malignancies. However, antigen escape and, more generally, heterogeneous antigen expression pose a challenge to applying CAR therapy to a wide range of cancers. We find that low-dose radiation sensitizes tumor cells to immune rejection by locally activated CAR T cells. In a model of pancreatic adenocarcinoma heterogeneously expressing sialyl Lewis-A (sLeA), we show that not only sLeA+ but also sLeA- tumor cells exposed to low-dose radiation become susceptible to CAR therapy, reducing antigen-negative tumor relapse. RNA sequencing analysis of low-dose radiation-exposed tumors reveals the transcriptional signature of cells highly sensitive to TRAIL-mediated death. We find that sLeA-targeted CAR T cells produce TRAIL upon engaging sLeA+ tumor cells, and eliminate sLeA- tumor cells previously exposed to systemic or local low-dose radiation in a TRAIL-dependent manner. These findings enhance the prospects for successfully applying CAR therapy to heterogeneous solid tumors. Local radiation is integral to many tumors' standard of care and can be easily implemented as a CAR conditioning regimen.

Outcomes of Relapsed and Refractory Primary Mediastinal (Thymic) Large B Cell Lymphoma Treated with Second-Line Therapy and Intent to Transplant.

Primary mediastinal (thymic) large B cell lymphoma is a subtype of diffuse large B cell lymphoma with distinct clinical, molecular, and genetic features, many of which overlap with Hodgkin lymphoma. Increasingly, initial therapy for these patients has used dose-dense chemotherapy with or without radiation with excellent results. In patients with relapsed and primary refractory disease, outcomes of second-line therapy followed by consolidation with high-dose therapy and autologous stem cell transplantation remains largely undefined. We reviewed the outcomes of 60 transplant-eligible patients with relapsed or refractory primary mediastinal (thymic) large B cell lymphoma enrolled on sequential protocols with uniform second-line therapy with intent to consolidate with autologous stem cell transplant. The estimated 3-year overall and event-free survivals for all patients were 61% and 57%, respectively, and 68% and 65%, respectively, for patients proceeding to stem cell transplant. Multivariable analysis of risk factors before transplant revealed that an incomplete response to initial therapy, advanced Ann Arbor stage at disease progression, and failure to achieve a partial remission or better to second-line therapy to be independently associated with inferior event-free and overall survival. A risk score based on these variables was able to identify patients who are unlikely to respond to conventional second-line strategies. These results suggest that salvage chemoradiotherapy with intent of subsequent high-dose therapy and autologous stem cell transplant is successful in most patients with relapsed and refractory primary mediastinal (thymic) large B cell lymphoma. Alternative strategies are warranted for a significant subset of patients with high-risk disease who are unlikely to be cured with this strategy.

Brentuximab vedotin and AVD followed by involved-site radiotherapy in early stage, unfavorable risk Hodgkin lymphoma.

This multicenter pilot study assessed the safety and efficacy of brentuximab vedotin (BV) and AVD (adriamycin, vinblastine, and dacarbazine) followed by 30 Gy involved site radiation therapy (ISRT). Patients with newly diagnosed, early stage classical Hodgkin lymphoma (HL) with unfavorable-risk features were treated with 4 cycles of BV and AVD. Patients who achieved a negative positron emission tomography (PET) scan (Deauville score of 1-3) received 30 Gy ISRT. Thirty patients received treatment and were assessable for toxicity. Twenty-nine patients completed 4 cycles of BV + AVD, and 25 patients BV + AVD + 30 Gy ISRT. No clinically significant noninfectious pneumonitis was observed. Serious adverse events (≥grade 3) were reported in 4 patients, including febrile neutropenia, peripheral neuropathy, and hypertension. After 2 and 4 cycles of BV + AVD, 90% (26 of 29) and 93% (27 or 29) of patients achieved a negative PET scan, respectively. Two patients with biopsy-proven primary refractory HL were treated off-study. All 25 patients who completed BV + AVD + ISRT achieved a complete response. With a median follow-up of 18.8 months, by intent to treat, the 1-year progression-free survival is 93.3% (95% confidence interval, 84-102). Overall, the treatment was well-tolerated with no evidence of significant pulmonary toxicity. The majority of patients (≥90%) achieved negative interim PET scans after 2 and 4 cycles of BV + AVD. Excluding the 2 primary refractory patients, all patients are disease free, suggesting that this is a highly active treatment program even in patients with substantial disease bulk. This trial was registered at www.clinicaltrials.gov as #NCT01868451.

NCCN Guidelines Insights: Multiple Myeloma, Version 3.2018.

The NCCN Guidelines for Multiple Myeloma provide recommendations for diagnosis, evaluation, treatment, including supportive-care, and follow-up for patients with myeloma. These NCCN Guidelines Insights highlight the important updates/changes specific to the myeloma therapy options in the 2018 version of the NCCN Guidelines.

NCCN Guidelines Insights: Hodgkin Lymphoma, Version 1.2018.

The NCCN Clinical Practice Guidelines in Oncology for Hodgkin Lymphoma (HL) provide recommendations for the management of adult patients with HL. The NCCN Guidelines Panel meets at least annually to review comments from reviewers within the NCCN Member Institutions, examine relevant data, and reevaluate and update the recommendations. These NCCN Guidelines Insights summarize recent updates centered on treatment considerations for relapsed/refractory classic HL.

Multiple Myeloma, Version 3.2017, NCCN Clinical Practice Guidelines in Oncology.

Multiple myeloma (MM) is caused by the neoplastic proliferation of plasma cells. These neoplastic plasma cells proliferate and produce monoclonal immunoglobulin in the bone marrow causing skeletal damage, a hallmark of multiple myeloma. Other MM-related complications include hypercalcemia, renal insufficiency, anemia, and infections. The NCCN Multiple Myeloma Panel members have developed guidelines for the management of patients with various plasma cell dyscrasias, including solitary plasmacytoma, smoldering myeloma, multiple myeloma, systemic light chain amyloidosis, and Waldenström's macroglobulinemia. The recommendations specific to the diagnosis and treatment of patients with newly diagnosed MM are discussed in this article.