Positron emission tomography-adapted therapy for first-line treatment in individuals with Hodgkin lymphoma

PET-adapted approaches to primary therapy for advanced Hodgkin lymphoma

Recent results of randomized phase III studies of FDG-PET-adapted therapy for advanced Hodgkin lymphoma (HL) have clearly demonstrated benefit to alteration of treatment according to interim response, in particular regarding reducing toxicity while maintaining efficacy. However, these studies have differences in design including initial chemotherapy regimen, PET response criteria, patient populations enrolled, and inclusion of radiation, and report different results regarding efficacy and toxicities, which makes cross-trial comparisons difficult. Practitioners are presented with deciding which of these approaches will provide the optimum outcome, balancing toxicity and efficacy, and for which patient with advanced-stage HL. This review summarizes the observations reported from these trials and provides context to help guide physicians and patients in treatment decisions for advanced HL.

Relapsing/refractory HL after autotransplantation: which treatment?

For advanced-stage Hodgkin lymphoma (HL), front-line chemotherapy, alone or in combination with radiotherapy, leads to 5-year progression-free survival (PFS) rates and freedom-from-treatment failure (FFTF) rates of 70-85%, regardless of the chemotherapy regimen applied. Patients with HL experiencing disease progression during or within 3 months of front-line therapy (primary refractory) and patients whose disease relapses after a complete response have a second chance of treatment. The standard of care for relapsed or refractory HL is second-line chemotherapy followed by autologous stem cell transplantation (ASCT), which can induce long-term remission in approximately 40-50% of patients. However, HL recurrence occurs in about 50% of patients after ASCT, usually within the first year, and represents a significant therapeutic challenge. Allogeneic transplantation from HLA-matched donors represents the standard of care for patients with HL relapsing after- or refractory to ASCT.

Interim PET-results for prognosis in adults with Hodgkin lymphoma: a systematic review and meta-analysis of prognostic factor studies

BACKGROUND

Hodgkin lymphoma (HL) is one of the most common haematological malignancies in young adults and, with cure rates of 90%, has become curable for the majority of individuals. Positron emission tomography (PET) is an imaging tool used to monitor a tumour's metabolic activity, stage and progression. Interim PET during chemotherapy has been posited as a prognostic factor in individuals with HL to distinguish between those with a poor prognosis and those with a better prognosis. This distinction is important to inform decision-making on the clinical pathway of individuals with HL.

OBJECTIVES

To determine whether in previously untreated adults with HL receiving first-line therapy, interim PET scan results can distinguish between those with a poor prognosis and those with a better prognosis, and thereby predict survival outcomes in each group.

SEARCH METHODS

We searched MEDLINE, Embase, CENTRAL and conference proceedings up until April 2019. We also searched one trial registry (ClinicalTrials.gov).

SELECTION CRITERIA

We included retrospective and prospective studies evaluating interim PET scans in a minimum of 10 individuals with HL (all stages) undergoing first-line therapy. Interim PET was defined as conducted during therapy (after one, two, three or four treatment cycles). The minimum follow-up period was at least 12 months. We excluded studies if the trial design allowed treatment modification based on the interim PET scan results.

DATA COLLECTION AND ANALYSIS

We developed a data extraction form according to the Checklist for Critical Appraisal and Data Extraction for Systematic Reviews of Prediction Modelling Studies (CHARMS). Two teams of two review authors independently screened the studies, extracted data on overall survival (OS), progression-free survival (PFS) and PET-associated adverse events (AEs), assessed risk of bias (per outcome) according to the Quality in Prognosis Studies (QUIPS) tool, and assessed the certainty of the evidence (GRADE). We contacted investigators to obtain missing information and data.

MAIN RESULTS

Our literature search yielded 11,277 results. In total, we included 23 studies (99 references) with 7335 newly-diagnosed individuals with classic HL (all stages). Participants in 16 studies underwent (interim) PET combined with computed tomography (PET-CT), compared to PET only in the remaining seven studies. The standard chemotherapy regimen included ABVD (16) studies, compared to BEACOPP or other regimens (seven studies). Most studies (N = 21) conducted interim PET scans after two cycles (PET2) of chemotherapy, although PET1, PET3 and PET4 were also reported in some studies. In the meta-analyses, we used PET2 data if available as we wanted to ensure homogeneity between studies. In most studies interim PET scan results were evaluated according to the Deauville 5-point scale (N = 12). Eight studies were not included in meta-analyses due to missing information and/or data; results were reported narratively. For the remaining studies, we pooled the unadjusted hazard ratio (HR). The timing of the outcome measurement was after two or three years (the median follow-up time ranged from 22 to 65 months) in the pooled studies. Eight studies explored the independent prognostic ability of interim PET by adjusting for other established prognostic factors (e.g. disease stage, B symptoms). We did not pool the results because the multivariable analyses adjusted for a different set of factors in each study. Overall survival Twelve (out of 23) studies reported OS. Six of these were assessed as low risk of bias in all of the first four domains of QUIPS (study participation, study attrition, prognostic factor measurement and outcome measurement). The other six studies were assessed as unclear, moderate or high risk of bias in at least one of these four domains. Four studies were assessed as low risk, and eight studies as high risk of bias for the domain other prognostic factors (covariates). Nine studies were assessed as low risk, and three studies as high risk of bias for the domain 'statistical analysis and reporting'. We pooled nine studies with 1802 participants. Participants with HL who have a negative interim PET scan result probably have a large advantage in OS compared to those with a positive interim PET scan result (unadjusted HR 5.09, 95% confidence interval (CI) 2.64 to 9.81, I² = 44%, moderate-certainty evidence). In absolute values, this means that 900 out of 1000 participants with a negative interim PET scan result will probably survive longer than three years compared to 585 (95% CI 356 to 757) out of 1000 participants with a positive result. Adjusted results from two studies also indicate an independent prognostic value of interim PET scan results (moderate-certainty evidence). Progression-free survival Twenty-one studies reported PFS. Eleven out of 21 were assessed as low risk of bias in the first four domains. The remaining were assessed as unclear, moderate or high risk of bias in at least one of the four domains. Eleven studies were assessed as low risk, and ten studies as high risk of bias for the domain other prognostic factors (covariates). Eight studies were assessed as high risk, thirteen as low risk of bias for statistical analysis and reporting. We pooled 14 studies with 2079 participants. Participants who have a negative interim PET scan result may have an advantage in PFS compared to those with a positive interim PET scan result, but the evidence is very uncertain (unadjusted HR 4.90, 95% CI 3.47 to 6.90, I² = 45%, very low-certainty evidence). This means that 850 out of 1000 participants with a negative interim PET scan result may be progression-free longer than three years compared to 451 (95% CI 326 to 569) out of 1000 participants with a positive result. Adjusted results (not pooled) from eight studies also indicate that there may be an independent prognostic value of interim PET scan results (low-certainty evidence). PET-associated adverse events No study measured PET-associated AEs.

AUTHORS' CONCLUSIONS

This review provides moderate-certainty evidence that interim PET scan results predict OS, and very low-certainty evidence that interim PET scan results predict progression-free survival in treated individuals with HL. This evidence is primarily based on unadjusted data. More studies are needed to test the adjusted prognostic ability of interim PET against established prognostic factors.

Interim PET-results for prognosis in adults with Hodgkin lymphoma: a systematic review and meta-analysis of prognostic factor studies

BACKGROUND

Hodgkin lymphoma (HL) is one of the most common haematological malignancies in young adults and, with cure rates of 90%, has become curable for the majority of individuals. Positron emission tomography (PET) is an imaging tool used to monitor a tumour's metabolic activity, stage and progression. Interim PET during chemotherapy has been posited as a prognostic factor in individuals with HL to distinguish between those with a poor prognosis and those with a better prognosis. This distinction is important to inform decision-making on the clinical pathway of individuals with HL.

OBJECTIVES

To determine whether in previously untreated adults with HL receiving first-line therapy, interim PET scan results can distinguish between those with a poor prognosis and those with a better prognosis, and thereby predict survival outcomes in each group.

SEARCH METHODS

We searched MEDLINE, Embase, CENTRAL and conference proceedings up until April 2019. We also searched one trial registry (ClinicalTrials.gov).

SELECTION CRITERIA

We included retrospective and prospective studies evaluating interim PET scans in a minimum of 10 individuals with HL (all stages) undergoing first-line therapy. Interim PET was defined as conducted during therapy (after one, two, three or four treatment cycles). The minimum follow-up period was at least 12 months. We excluded studies if the trial design allowed treatment modification based on the interim PET scan results.

DATA COLLECTION AND ANALYSIS

We developed a data extraction form according to the Checklist for Critical Appraisal and Data Extraction for Systematic Reviews of Prediction Modelling Studies (CHARMS). Two teams of two review authors independently screened the studies, extracted data on overall survival (OS), progression-free survival (PFS) and PET-associated adverse events (AEs), assessed risk of bias (per outcome) according to the Quality in Prognosis Studies (QUIPS) tool, and assessed the certainty of the evidence (GRADE). We contacted investigators to obtain missing information and data.

MAIN RESULTS

Our literature search yielded 11,277 results. In total, we included 23 studies (99 references) with 7335 newly-diagnosed individuals with classic HL (all stages).Participants in 16 studies underwent (interim) PET combined with computed tomography (PET-CT), compared to PET only in the remaining seven studies. The standard chemotherapy regimen included ABVD (16) studies, compared to BEACOPP or other regimens (seven studies). Most studies (N = 21) conducted interim PET scans after two cycles (PET2) of chemotherapy, although PET1, PET3 and PET4 were also reported in some studies. In the meta-analyses, we used PET2 data if available as we wanted to ensure homogeneity between studies. In most studies interim PET scan results were evaluated according to the Deauville 5-point scale (N = 12).Eight studies were not included in meta-analyses due to missing information and/or data; results were reported narratively. For the remaining studies, we pooled the unadjusted hazard ratio (HR). The timing of the outcome measurement was after two or three years (the median follow-up time ranged from 22 to 65 months) in the pooled studies.Eight studies explored the independent prognostic ability of interim PET by adjusting for other established prognostic factors (e.g. disease stage, B symptoms). We did not pool the results because the multivariable analyses adjusted for a different set of factors in each study.Overall survivalTwelve (out of 23) studies reported OS. Six of these were assessed as low risk of bias in all of the first four domains of QUIPS (study participation, study attrition, prognostic factor measurement and outcome measurement). The other six studies were assessed as unclear, moderate or high risk of bias in at least one of these four domains. Nine studies were assessed as high risk, and three studies as moderate risk of bias for the domain study confounding. Eight studies were assessed as low risk, and four studies as high risk of bias for the domain statistical analysis and reporting.We pooled nine studies with 1802 participants. Participants with HL who have a negative interim PET scan result probably have a large advantage in OS compared to those with a positive interim PET scan result (unadjusted HR 5.09, 95% confidence interval (CI) 2.64 to 9.81, I² = 44%, moderate-certainty evidence). In absolute values, this means that 900 out of 1000 participants with a negative interim PET scan result will probably survive longer than three years compared to 585 (95% CI 356 to 757) out of 1000 participants with a positive result.Adjusted results from two studies also indicate an independent prognostic value of interim PET scan results (moderate-certainty evidence).Progression-free survival Twenty-one studies reported PFS. Eleven out of 21 were assessed as low risk of bias in the first four domains. The remaining were assessed as unclear, moderate or high risk of bias in at least one of the four domains. Eleven studies were assessed as high risk, nine studies as moderate risk and one study as low risk of bias for study confounding. Eight studies were assessed as high risk, three as moderate risk and nine as low risk of bias for statistical analysis and reporting.We pooled 14 studies with 2079 participants. Participants who have a negative interim PET scan result may have an advantage in PFS compared to those with a positive interim PET scan result, but the evidence is very uncertain (unadjusted HR 4.90, 95% CI 3.47 to 6.90, I² = 45%, very low-certainty evidence). This means that 850 out of 1000 participants with a negative interim PET scan result may be progression-free longer than three years compared to 451 (95% CI 326 to 569) out of 1000 participants with a positive result.Adjusted results (not pooled) from eight studies also indicate that there may be an independent prognostic value of interim PET scan results (low-certainty evidence).PET-associated adverse eventsNo study measured PET-associated AEs.

AUTHORS' CONCLUSIONS

This review provides moderate-certainty evidence that interim PET scan results predict OS, and very low-certainty evidence that interim PET scan results predict progression-free survival in treated individuals with HL. This evidence is primarily based on unadjusted data. More studies are needed to test the adjusted prognostic ability of interim PET against established prognostic factors.

Eichenauer* D, Jakob T, Follmann M, Engert A, Skoetz N. Hodgkin Lymphoma in Adults

BACKGROUND

Hodgkin lymphoma is the most common neoplasm in young adults, with an incidence of 2 to 3 cases per 100 000 persons per year. Risk-adapted chemotherapy and radiotherapy usually lead to cure. Finding ways to lessen the treatment- associated morbidity and mortality is a major goal of current research.

METHODS

For the creation of an updated guideline (DKH grant number 111778), a systematic literature search was carried out in medical databases (MEDLINE, CENTRAL) and guideline databases (GIN) (search dates: January 2012 to June 2017).

RESULTS

Results from 10 meta-analyses, 89 randomized and controlled trials, and 81 prospective or retrospective trials were evaluated. The use of positron emission tomography (PET) is strongly recommended in the initial diagnostic evaluation, as well as for the guidance of treatment in advanced stages. In early stages, two cycles of ABVD (doxorubicin, bleomycin, vinblastine, and dacarbazine) and involved-site radiotherapy (IS-RT) at a dose of 20 Gy are recommended. For the treatment of intermedi- ate stages, two cycles of escalated BEACOPP (bleomycin, etoposide, doxorubicin, cyclophosphamide, vincristine, procarbazine, and prednisone) + two cycles of ABVD and 30 Gy IS-RT are recommended. In advanced stages, two cycles of escalated BEACOPP are administered, and then PET is performed for the guidance of further treatment: two further cycles of escalated BEACOPP are recommended if the PET is negative and four further cycles if it is positive, followed by radiotherapy of PET- positive residual tumor tissue. The five-year survival of patients with Hodgkin lymphoma is 95%. In case of disease recurrence, high-dose chemotherapy followed by autologous stem-cell transplantation is performed, and targeted drugs including brentuxi- mab vedotin, nivolumab, and pembrolizuab are used.

CONCLUSION

The highly favorable long-term prognosis of HL necessitates careful consideration of the intensity of treatment as well as thorough follow-up to enable the detection of late sequelae, such as second tumors or organ damage.

[18F]FDG-PET/CT in Hodgkin Lymphoma: Current Usefulness and Perspectives

Functional imaging using 18-fluorodeoxyglycose ([¹⁸F]FDG) positron emission tomography combined with computed tomography (PET/CT) has become a major imaging modality in Hodgkin lymphoma. This imaging modality allows for a significant improvement in staging, increased sensitivity, which involves differentiating residual tumors from fibrosis during assessment, and highly impacts treatment decisions into new PET-driven strategies. This review presents the main scientific data concerning the current applications of [¹⁸F]FDG-PET/CT in Hodgkin lymphoma at baseline, interim, and the end of treatment evaluation along with the main PET-driven trials for therapeutic decisions. The emergence of total metabolic tumor volume as a new functional prognostic factor will also be discussed.

Infradiaphragmatic Hodgkin lymphoma: a large series of patients staged with PET-CT

Introduction

Infradiaphragmatic Hodgkin Lymphoma (IDHL) accounts for 3-11% of adult cases of stage I-II Hodgkin Lymphoma and the treatment strategy in IDHL is still heterogeneous. All previous published studies were conducted before the PET-CT era. PET may provide a more accurate evaluation of IDHL stage. The aim of this study was to analyze the clinical and biological characteristics of IDHL patients staged by CT scan or PET-CT in eight French hematology departments and their impact on outcomes in these patients.

Methods

Baseline clinical and biological data and outcomes in patients with a first diagnosis of stage I-II IDHL treated with ABVD +/- radiotherapy were retrospectively collected.

Results

Among the 99 patients included, 65 (66%) were staged with PET-CT. These patients were older (53 years vs 46 years, p=0.043), had lower ESR (27 vs 58mm, p=0.022), higher hemoglobin level (13.6 vs 12.8g/dL, p=0.015), less frequent Ann Arbor stage II (74% vs 91%) and less central adenopathy involvement (60% vs 82%, p=0.024). Treatment was chemotherapy alone in 55% of patients and the remaining patients received chemo-radiotherapy (CRT). Five-year PFS and OS rates in PET-CT-staged patients were 78% (95% CI 64-87) and 88% (95% CI 73-95), respectively, compared with 65% (p=0.225) and 82% (p=0.352) in CT-staged patients. The CRT strategy was associated with fewer relapses (p=0.027).

Conclusion

This study showed that the characteristics of CT-staged IDHL patients were less favorable than those of PET-CT-staged patients and indicated that CRT provided better PFS than did chemotherapy alone.

Chemotherapy alone versus chemotherapy plus radiotherapy for adults with early stage Hodgkin lymphoma

BACKGROUND

Combined modality treatment consisting of chemotherapy followed by localised radiotherapy is the standard treatment for patients with early stage Hodgkin lymphoma (HL). However, due to long- term adverse effects such as secondary malignancies the role of radiotherapy has been questioned recently and some clinical study groups advocate chemotherapy only for this indication.

OBJECTIVES

To assess the effects of chemotherapy alone compared to chemotherapy plus radiotherapy in adults with early stage HL .

SEARCH METHODS

For the or i ginal version of this review, we searched MEDLINE, Embase and CENTRAL as well as conference proceedings (American Society of Hematology, American Society of Clinical Oncology and International Symposium of Hodgkin Lymphoma) from January 1980 to November 2010 for randomised controlled trials (RCTs) comparing chemotherapy alone versus chemotherapy regimens plus radiotherapy. For the updated review we searched MEDLINE, CENTRAL and conference proceedings to December 2016.

SELECTION CRITERIA

We included RCTs comparing chemotherapy alone with chemotherapy plus radiotherapy in patients with early stage HL. We excluded trials with more than 20% of patients in advanced stage. As the value of radiotherapy in addition to chemotherapy is still not clear, we also compared to more cycles of chemotherapy in the control arm. In this updated review, we also included a second comparison evaluating trials with varying numbers of cycles of chemotherapy between intervention and control arms, same chemotherapy regimen in both arms assumed. We excluded trials evaluating children only, therefore only trials involving adults are included in this updated review.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data and assessed the quality of trials. We contacted study authors to obtain missing information. As effect measures we used hazard ratios (HR) for overall survival (OS) and progression-free survival (PFS) and risk ratios (RR) for response rates. Since not all trials reported PFS according to our definitions, we evaluated all similar outcomes (e.g. event-free survival) as PFS/tumour control.

MAIN RESULTS

Our search led to 5518 potentially relevant references. From these, we included seven RCTs in the analyses involving 2564 patients. In contrast to the first version of this review including five trials, we excluded trials randomising children. As a result, we excluded one trial from the former analyses and we identified three new trials.Five trials with 1388 patients compared the combination of chemotherapy alone and chemotherapy plus radiotherapy, with the same number of chemotherapy cycles in both arms. The addition of radiotherapy to chemotherapy has probably little or no difference on OS (HR 0.48; 95% confidence interval (CI) 0.22 to 1.06; P = 0.07, moderate- quality evidence), however two included trials had potential other high risk of bias due to a high number of patients not receiving planned radiotherapy. After excluding these trials in a sensitivity analysis, the results showed that the combination of chemotherapy and radiotherapy improved OS compared to chemotherapy alone (HR 0.31; 95% CI 0.19 to 0.52; P <0.00001, moderate- quality evidence). In contrast to chemotherapy alone the use of chemotherapy and radiotherapy improved PFS (HR 0.42; 95% CI 0.25 to 0.72; P = 0.001; moderate- quality evidence). Regarding infection- related mortality (RR 0.33; 95% CI 0.01 to 8.06; P = 0.5; low- quality evidence), second cancer- related mortality (RR 0.53; 95% CI 0.07 to 4.29; P = 0.55; low- quality evidence) and cardiac disease- related mortality (RR 2.94; 95% CI 0.31 to 27.55; P = 0.35;low- quality evidence), there is no evidence for a difference between the use of chemotherapy alone and chemotherapy plus radiotherapy. For complete response rate (CRR) (RR 1.08; 95% CI 0.93 to 1.25; P = 0.33; low- quality evidence), there is also no evidence for a difference between treatment groups.Two trials with 1176 patients compared the combination of chemotherapy alone and chemotherapy plus radiotherapy, with different numbers of chemotherapy cycles in both arms. OS is reported in one trial only, the use of chemotherapy alone (more chemotherapy cycles) may improve OS compared to chemotherapy plus radiotherapy (HR 2.12; 95% CI 1.03 to 4.37; P = 0.04; low- quality evidence). This trial also had a potential other high risk of bias due to a high number of patients not receiving planned therapy. There is no evidence for a difference between chemotherapy alone and chemotherapy plus radiotherapy regarding PFS (HR 0.42; 95% CI 0.14 to 1.24; P = 0.12; low- quality evidence). After excluding the trial with patients not receiving the planned therapy in a sensitivity analysis, the results showed that the combination of chemotherapy and radiotherapy improved PFS compared to chemotherapy alone (HR 0.24; 95% CI 0.070 to 0.88; P = 0.03, based on one trial). For infection- related mortality (RR 6.90; 95% CI 0.36 to 132.34; P = 0.2; low- quality evidence), second cancer- related mortality (RR 2.22; 95% CI 0.7 to 7.03; P = 0.18; low- quality evidence) and cardiac disease-related mortality (RR 0.99; 95% CI 0.14 to 6.90; P = 0.99; low-quality evidence), there is no evidence for a difference between the use of chemotherapy alone and chemotherapy plus radiotherapy. CRR rate was not reported.

AUTHORS' CONCLUSIONS

This systematic review compared the effects of chemotherapy alone and chemotherapy plus radiotherapy in adults with early stage HL .For the comparison with same numbers of chemotherapy cycles in both arms, we found moderate- quality evidence that PFS is superior in patients receiving chemotherapy plus radiotherapy than in those receiving chemotherapy alone. The addition of radiotherapy to chemotherapy has probably little or no difference on OS . The sensitivity analysis without the trials with potential other high risk of bias showed that chemotherapy plus radiotherapy improves OS compared to chemotherapy alone.For the comparison with different numbers of chemotherapy cycles between the arms there are no implications for OS and PFS possible, because of the low quality of evidence of the results.

The Landscape of Clinical Trials Evaluating the Theranostic Role of PET Imaging in Oncology: Insights from an Analysis of ClinicalTrials.gov Database

In the war on cancer marked by personalized medicine, positron emission tomography (PET)-based theranostic strategy is playing an increasingly important role. Well-designed clinical trials are of great significance for validating the PET applications and ensuring evidence-based cancer care. This study aimed to provide a comprehensive landscape of the characteristics of PET clinical trials using the substantial resource of ClinicalTrials.gov database. We identified 25,599 oncology trials registered with ClinicalTrials.gov in the last ten-year period (October 2005-September 2015). They were systematically reviewed to validate classification into 519 PET trials and 25,080 other oncology trials used for comparison. We found that PET trials were predominantly phase 1-2 studies (86.2%) and were more likely to be single-arm (78.9% vs. 57.9%, P <0.001) using non-randomized assignment (90.1% vs. 66.7%, P <0.001) than other oncology trials. Furthermore, PET trials were small in scale, generally enrolling fewer than 100 participants (20.3% vs. 25.7% for other oncology trials, P = 0.014), which might be too small to detect a significant theranostic effect. The funding support from industry or National Institutes of Health shrunk over time (both decreased by about 5%), and PET trials were more likely to be conducted in only one region lacking international collaboration (97.0% vs. 89.3% for other oncology trials, P <0.001). These findings raise concerns that clinical trials evaluating PET imaging in oncology are not receiving the attention or efforts necessary to generate high-quality evidence. Advancing the clinical application of PET imaging will require a concerted effort to improve the quality of trials.

Comparing the accuracy of quantitative versus qualitative analyses of interim PET to prognosticate Hodgkin lymphoma: a systematic review protocol of diagnostic test accuracy

INTRODUCTION

Hodgkin lymphoma is an effectively treated malignancy, yet 20% of patients relapse or are refractory to front-line treatments with potentially fatal outcomes. Early detection of poor treatment responders is crucial for appropriate application of tailored treatment strategies. Tumour metabolic imaging of Hodgkin lymphoma using visual (qualitative) 18-fluorodeoxyglucose positron emission tomography (FDG-PET) is a gold standard for staging and final outcome assessment, but results gathered during the interim period are less accurate. Analysis of continuous metabolic-morphological data (quantitative) FDG-PET may enhance the robustness of interim disease monitoring, and help to improve treatment decision-making processes. The objective of this review is to compare diagnostic test accuracy of quantitative versus qualitative interim FDG-PET in the prognostication of patients with Hodgkin lymphoma.

METHODS

The literature on this topic will be reviewed in a 3-step strategy that follows methods described by the Joanna Briggs Institute (JBI). First, MEDLINE and EMBASE databases will be searched. Second, listed databases for published literature (MEDLINE, Tripdatabase, Pedro, EMBASE, the Cochrane Central Register of Controlled Trials and WoS) and unpublished literature (Open Grey, Current Controlled Trials, MedNar, ClinicalTrials.gov, Cos Conference Papers Index and International Clinical Trials Registry Platform of the WHO) will be queried. Third, 2 independent reviewers will analyse titles, abstracts and full texts, and perform hand search of relevant studies, and then perform critical appraisal and data extraction from selected studies using the DATARI tool (JBI). If possible, a statistical meta-analysis will be performed on pooled sensitivity and specificity data gathered from the selected studies. Statistical heterogeneity will be assessed. Funnel plots, Begg's rank correlations and Egger's regression tests will be used to detect and/or correct publication bias.

ETHICS AND DISSEMINATION

The results will be disseminated by publishing in a peer-reviewed journal. Ethical assessment will not be needed; only existing sources of literature will be searched.

TRIAL REGISTRATION NUMBER

CRD42016027953.

Hodgkin Lymphoma: the Changing Role of Radiation Therapy in Early-Stage Disease—the Role of Functional Imaging

Early-stage classical Hodgkin lymphoma (CHL) is a highly curable malignancy. Historically, extended-field radiotherapy (EFRT) alone showed excellent cure rates, but the risk of radiotherapy (RT)-associated toxicities led to combined modality therapy (CMT) replacing RT alone. RT has subsequently evolved further with significant reductions of dose and field size, and is currently restricted to involved sites only (ISRT). Contemporary CMT yields cure rates in excess of 85%, and most studies do not have adequate follow-up required to evaluate the risk reduction in late effects. In an effort to avoid RT altogether, response-adapted treatment approaches utilizing results of interim [(18)F]fluorodeoxyglucose (FDG) positron emission tomography with fused computed tomography (PET/CT) imaging have been studied. Results from two studies in favorable-risk (UK RAPID and EORTC H10F) and one in unfavorable-risk patients (EORTC H10U) suggest that omission of RT in patients with a negative interim PET/CT response (Deauville score ≤2) yields slightly inferior progression-free survival (PFS) compared to conventional CMT, but with no difference in overall survival (OS) albeit with short-term follow-up. In order to extrapolate results to daily practice, it is critical to understand the selection of patients entered on trials since definitions of favorable and unfavorable disease vary between study groups. Currently, CMT continues to be the standard of care for the vast majority of patients with early-stage CHL and RT is an integral part of therapy in patients with bulky disease. However, for selected patients with favorable characteristics, emerging data suggest that a chemotherapy-alone approach is reasonable.

Involved site radiation therapy for the treatment of early-stage Hodgkin lymphoma in adolescents and young adults

Radiation therapy technology has permitted the development of new treatment planning techniques. Involved field, involved node, and involved site radiotherapy fields are discussed and compared. Indications for and implications of combined modality therapy are examined, particularly as pertinent to the adolescent and young adult population.