Point/counterpoint: early-stage Hodgkin lymphoma and the role of radiation therapy

The results of recent clinical trials for the management of limited-stage Hodgkin lymphoma have led to considerable debate, especially regarding the role of radiation therapy. This review highlights those recent trials and provides perspectives regarding their interpretation from a radiation oncologist and a hematologist. The trial protocol is available at http://www.nejm.org/doi/suppl/10.1056/NEJMoa1111961/suppl_file/nejmoa1111961_protocol.pdf.

Hodgkin lymphoma: 2012 update on diagnosis, risk-stratification, and management

DISEASE OVERVIEW

Hodgkin lymphoma (HL) is an uncommon B-cell lymphoid malignancy affecting 9,000 new patients annually and representing approximately 11% of all lymphomas in the United States.

DIAGNOSIS

HL is composed of two distinct disease entities; the more commonly diagnosed classical HL and the rare nodular lymphocyte predominant HL. Nodular sclerosis, mixed cellularity, lymphocyte depletion, and lymphocyte-rich HL are subgroups under the designation of classical HL.

RISK STRATIFICATION

An accurate assessment of the stage of disease in patients with HL is critical for the selection of the appropriate therapy. Prognostic models that identify patients at low or high risk for recurrence are used to optimize therapy for patients with limited or advanced stage disease.

RISK-ADAPTED THERAPY

Initial therapy for HL patients is based on the histology of the disease, the anatomical stage and the presence of poor prognostic features. Patients with early stage disease are treated with combined modality strategies utilizing abbreviated courses of combination chemotherapy followed by involved-field radiation therapy, while those with advanced stage disease receive a longer course of chemotherapy often without radiation therapy.

MANAGEMENT OF REFRACTORY DISEASE

High-dose chemotherapy (HDCT) followed by an autologous stem cell transplant (ASCT) is the standard of care for most patients who relapse following initial therapy. For patients who fail HDCT with ASCT, brentuximab vedotin, palliative chemotherapy, non-myeloablative allogeneic transplant or participation in a clinical trial should be considered.

Involved node radiation therapy: an effective alternative in early-stage hodgkin lymphoma

PURPOSE

The involved node radiation therapy (INRT) strategy was introduced for patients with Hodgkin lymphoma (HL) to reduce the risk of late effects. With INRT, only the originally involved lymph nodes are irradiated. We present treatment outcome in a retrospective analysis using this strategy in a cohort of 97 clinical stage I-II HL patients.

METHODS AND MATERIALS

Patients were staged with positron emission tomography/computed tomography scans, treated with adriamycin, bleomycin, vinblastine, and dacarbazine chemotherapy, and given INRT (prechemotherapy involved nodes to 30 Gy, residual masses to 36 Gy). Patients attended regular follow-up visits until 5 years after therapy.

RESULTS

The 4-year freedom from disease progression was 96.4% (95% confidence interval: 92.4%-100.4%), median follow-up of 50 months (range: 4-71 months). Three relapses occurred: 2 within the previous radiation field, and 1 in a previously uninvolved region. The 4-year overall survival was 94% (95% confidence interval: 88.8%-99.1%), median follow-up of 58 months (range: 4-91 months). Early radiation therapy toxicity was limited to grade 1 (23.4%) and grade 2 (13.8%). During follow-up, 8 patients died, none from HL, 7 malignancies were diagnosed, and 5 patients developed heart disease.

CONCLUSIONS

INRT offers excellent tumor control and represents an effective alternative to more extended radiation therapy in the combined modality treatment for early-stage HL.

Point/counterpoint: early-stage Hodgkin lymphoma and the role of radiation therapy

The results of recent clinical trials for the management of limited-stage Hodgkin lymphoma have led to considerable debate, especially regarding the role of radiation therapy. This review highlights those recent trials and provides perspectives regarding their interpretation from a radiation oncologist and a hematologist. The trial protocol is available at http://www.nejm.org/doi/suppl/10.1056/NEJMoa1111961/suppl_file/nejmoa1111961_protocol.pdf.

Routine bone marrow biopsy has little or no therapeutic consequence for positron emission tomography/computed tomography-staged treatment-naive patients with Hodgkin lymphoma

PURPOSE

To investigate whether bone marrow biopsy (BMB) adds useful information to [(18)F]fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) staging in patients with Hodgkin lymphoma (HL).

PATIENTS AND METHODS

Newly diagnosed patients with HL undergoing a pretherapeutic staging that encompasses both PET/CT and BMB were included in this retrospective study. The pattern of skeletal FDG uptake was categorized as uni-, bi-, or multifocal (≥ three lesions). Clinical stage, risk assessment, and treatment plan were determined with and without the contribution of BMB results according to the Ann Arbor classification and the guidelines from the German Hodgkin Study Group.

RESULTS

A total of 454 patients with HL were included of whom 82 (18%) had focal skeletal PET/CT lesions and 27 (6%) had positive BMB. No patients with positive BMB were assessed as having stage I to II disease by PET/CT staging. BMB upstaged five patients, assessed as being stage III before BMB; none of the 454 patients would have been allocated to another treatment on the basis of BMB results. Focal skeletal PET/CT lesions identified positive and negative BMBs with a sensitivity and specificity of 85% and 86%, respectively. The positive and negative predictive values of focal skeletal PET/CT lesions for BMB results were 28% and 99%, respectively.

CONCLUSION

A consistent finding of this study was the absence of positive BMBs in PET/CT-assessed stage I to II disease. The omission of staging BMB would not have changed the risk assessment or treatment strategy in this cohort of 454 newly diagnosed patients with HL.

Efficacy of abbreviated Stanford V chemotherapy and involved-field radiotherapy in early-stage Hodgkin lymphoma: mature results of the G4 trial

INTRODUCTION

To assess the efficacy of an abbreviated Stanford V regimen in patients with early-stage Hodgkin lymphoma (HL). PATIENTS AND METHODS PATIENTS: with untreated nonbulky stage I-IIA supradiaphragmatic HL were eligible for the G4 study. Stanford V chemotherapy was administered for 8 weeks followed by radiation therapy (RT) 30 Gy to involved fields (IF). Freedom from progression (FFP), disease-specific survival (DSS) and overall survival (OS) were estimated.

RESULTS

All 87 enrolled patients completed the abbreviated regimen. At a median follow-up of 10 years, FFP, DSS and OS are 94%, 99% and 94%, respectively. Therapy was well tolerated with no treatment-related deaths.

CONCLUSIONS

Mature results of the abbreviated Stanford V regimen in nonbulky early-stage HL are excellent and comparable to the results from other contemporary therapies.

Stage-adapted treatment of HIV-associated Hodgkin lymphoma: results of a prospective multicenter study

PURPOSE

Although the outcome of patients with HIV-related Hodgkin lymphoma (HIV-HL) has markedly improved since the introduction of combined antiretroviral therapy, standard therapy is still poorly defined. This prospective study investigates a stage- and risk-adapted treatment strategy in patients with HIV-HL.

PATIENTS AND METHODS

Patients with early favorable HIV-HL received two to four cycles of doxorubicin, bleomycin, vinblastine, and dacarbazine (ABVD) followed by 30 Gy of involved-field (IF) radiation. In patients with early unfavorable HIV-HL, four cycles of bleomycin, etoposide, doxorubicin, cyclophosphamide, vincristine, procarbazine, and prednisone (BEACOPP baseline) or four cycles of ABVD + 30 Gy of IF radiation were administered. Six to eight cycles of BEACOPP baseline were given in patients with advanced-stage HIV-HL. In patients with advanced HIV infection, BEACOPP was replaced with ABVD.

RESULTS

Of 108 patients (including eight female patients) included in the study, 23 (21%) had early favorable HL, 14 (13%) had early unfavorable HL, and 71 (66%) had advanced-stage HL. The median CD4 count at HL diagnosis was 240/μL. The complete remission rates for patients with early favorable, early unfavorable, and advanced-stage HL were 96%, 100%, and 86%, respectively. The 2-year progression-free survival of the entire study population was 91.7%. Eleven patients (11%) have died, and treatment-related mortality was 5.6%. The 2-year overall survival rate was 90.7% with no significant difference between early favorable (95.7%), early unfavorable (100%), and advanced-stage HL (86.8%).

CONCLUSION

In patients with HIV-HL, stage- and risk-adapted treatment is feasible and effective. The prognosis for patients with HIV-HL may approach that of HIV-negative patients with HL.

Tailored strategies for radiation therapy in classical Hodgkin's lymphoma

Radiotherapeutic advances have contributed to the evolution of Hodgkin's lymphoma (HL) treatment paradigms. A reduction in radiation therapy (RT) field size and dose has the potential to significantly impact the therapeutic ratio by diminishing late toxicities while maintaining curability. Substantial progress in risk stratification has contributed to the development of tailored RT strategies which address both field design as well as dose. Technologic improvements have also enhanced the ability to adapt the RT technique to the individual patient. The refinement of the RT approach and its incorporation into current combined modality strategies in adult classical HL is the subject of ongoing investigation and is critically reviewed.

Hodgkin's lymphoma in adults

Management of Hodgkin's lymphoma continues to develop. Outcomes for patients with favourable-risk, early-stage disease are excellent, and serial reductions in intensity of treatment have been made to retain the excellent prognosis while reducing the late effects of treatment. Prognosis is also very good in advanced-stage disease but the rate of relapse is higher than in early-stage disease, and the optimum first-line treatment is unclear. Workers are investigating the role of functional imaging to assess whether treatment can be tailored according to response, with the most intensive therapies reserved for patients predicted to have poor outcomes. In this Seminar we critically appraise the management of Hodgkin's lymphoma in early-stage disease, advanced-stage disease, and at relapse, with a focus on late effects of treatment.

Interim [(18)F]fluorodeoxyglucose positron emission tomography imaging in stage I-II non-bulky Hodgkin lymphoma: would using combined positron emission tomography and computed tomography criteria better predict response than each test alone?

Our objective was to validate the International Harmonization Project (IHP) positron emission tomography (PET) response criteria and correlate with the Deauville criteria and diagnostic computed tomography-based (dCT) lesion size changes. All patients were recruited prospectively to the Cancer and Leukemia Group B (CALGB) 50203 trial for the treatment of stage I-II, non-bulky Hodgkin lymphoma (HL). [(18)F]Fluorodeoxyglucose (FDG) PET and dCT were performed at baseline and after two doxorubicin, vinblastine and gemcitabine (AVG) cycles (PET-2, dCT-2) in 88 patients. IHP and Deauville criteria and percent decrease in the sum of the products of the perpendicular diameters (%SPPD) after two cycles were correlated with progression-free survival (PFS). After a median follow-up of 3.3 years, 23.9% of patients relapsed/progressed (3-year PFS 77%). By IHP, the 2-year PFS was 88% and 54% for PET-2 negative and positive groups, respectively (p = 0.0009). Similar results were obtained for Deauville criteria. In a univariate analysis, PET-2 predicted PFS better than %SPPD, and in a combinatorial analysis, in the PET-2 positive group, a negative dCT-2 increased PFS by 27-35%. However, some confidence intervals were large due to small sample sizes. In conclusion, IHP and Deauville criteria-based interpretation of PET-2 was strongly associated with 2-year PFS. The combined analysis of PET-2 with dCT-2 suggested a better predictive value for PFS compared to either test alone. Further studies are under way to confirm these findings.

Recommendations for the use of radiotherapy in nodal lymphoma

These guidelines have been developed to define the use of radiotherapy for lymphoma in the current era of combined modality treatment taking into account increasing concern over the late side-effects associated with previous radiotherapy. The role of reduced volume and reduced doses is addressed, integrating modern imaging with three-dimensional planning and advanced techniques of treatment delivery. Both wide-field and involved-field techniques have now been supplanted by the use of defined volumes based on node involvement shown on computed tomography (CT) and positron emission tomography (PET) imaging and applying the International Commission on Radiation Units and Measurements concepts of gross tumour volume (GTV), clinical target volume (CTV) and planning target volume (PTV). The planning of lymphoma patients for radical radiotherapy should now be based upon contrast enhanced 3 mm contiguous CT with three-dimensional definition of volumes using the convention of GTV, CTV and PTV. The involved-site radiotherapy concept defines the CTV based on the PET-defined pre-chemotherapy sites of involvement with an expansion in the cranio-caudal direction of lymphatic spread by 1.5 cm, constrained to tissue planes such as bone, muscle and air cavities. The margin allows for uncertainties in PET resolution, image registration and changes in patient positioning and shape. There is increasing evidence in both Hodgkin and non-Hodgkin lymphoma that traditional doses are higher than necessary for disease control and related to the incidence of late effects. No more than 30 Gy for Hodgkin and aggressive non-Hodgkin lymphoma and 24 Gy for indolent lymphomas is recommended; lower doses of 20 Gy in combination therapy for early-stage low-risk Hodgkin lymphoma may be sufficient. As yet there are no large datasets validating the use of involved-site radiotherapy; these will emerge from the current generation of clinical trials. Radiotherapy remains the most effective single modality in the treatment of lymphoma. A reduction in both treatment volume and overall treatment dose should now be considered to minimise the risks of late sequelae. However, it is important that this is not at the expense of the excellent disease control currently achieved.

Role of modern radiation therapy in early stage Hodgkin's lymphoma: A young radiation oncologists' perspective

The role of radiotherapy is well established in combined modality programs for early stage Hodgkin's lymphoma, but still debated with regards to late toxicity issues. Modern radiotherapy prescribing attitudes include lower doses and smaller fields, together with the implementation of sophisticated and dedicated delivery techniques. Aim of this review is to briefly discuss the current role of radiotherapy in this field and the potential future developments. Major trials conducted in recent years in early stage Hodgkin's lymphoma are critically reviewed and discussed with a focus on radiotherapy-related issues and with an attention to current treatment options by a "young" radiation oncologists' perspective.

State of the art in the treatment of Hodgkin lymphoma

Hodgkin lymphoma (HL) has become one of the most easily curable malignancies in oncology. More than 80% of patients can be cured with risk-adapted treatment that includes chemotherapy and radiotherapy. This progress is mainly due to the development of multi-agent chemotherapy and improved radiation techniques; however, severe, life-threatening treatment-related side effects occur, which include organ toxicity and secondary malignancies. Thus, the treatment approaches must be carefully balanced between optimal disease control and the risk of long-term sequelae. Although this article is meant to provide an overview of the current treatment approaches for patients with HL, in many instances conflicting results from various clinical trials are available, and a personal judgment is inevitable. Here, we focus on evidence from large clinical trials with solid conclusions.

Involved field radiation for Hodgkin's lymphoma: the actual dose to breasts in close proximity

To decrease the risk of late toxicities in Hodgkin's lymphoma (HL) patients treated with radiation therapy (RT) (HL), involved field radiation therapy (IFRT) has largely replaced the extended fields. To determine the out-of-field dose delivered from a typical IFRT to surrounding critical structures, we measured the dose at various points in an anthropomorphic phantom. The phantom is divided into 1-inch-thick slices with the ability to insert TLDs at 3-cm intervals grid spacing. Two treatment fields were designed, and a total of 45 TLDs were placed (equally spaced) at the margin of the each of the 2 radiation fields. After performing a computed tomography simulation, 2 treatment plans targeting the mediastinum, a typical treatment field in patients with early stage HL, were generated. A total dose of 3060 cGy was delivered to the gross tumor volume for each field consecutively. The highest measured dose detected at 1 cm from the field edge in the planning target volume was 496 cGy, equivalent to 16% of the isocentric dose. The dose dropped significantly with increasing distance from the field edge. It ranged from 1.1-3.9% of the isocentric dose at a distance of 3.2-4 cm to <1.6% at a distance of >6 cm. Although the computer treatment planning system (CTPS) frequently underestimated the dose delivered, the difference in dose between measured and generated by CTPS was <2.5% in 90 positions measured. The collateral dose of radiation to breasts from IFRT is minimal. The out-of-field dose, although mildly underestimated by CTPS, becomes insignificant at >3 cm from the field edge of the radiation field.

Dose-Intensification in Early Unfavorable Hodgkin's Lymphoma: Final Analysis of the German Hodgkin Study Group HD14 Trial

Purpose

In patients with early unfavorable Hodgkin's lymphoma (HL), combined modality treatment with four cycles of ABVD (adriamycin, bleomycin, vinblastine, and dacarbazine) and 30 Gy involved-field radiotherapy (IFRT) results in long-term tumor control of approximately 80%. We aimed to improve these results using more intensive chemotherapy.

Patients and Methods

Patients with newly diagnosed early unfavorable HL were randomly assigned to either four cycles of ABVD or an intensified treatment consisting of two cycles of escalated BEACOPP (bleomycin, etoposide, adriamycin, cyclophosphamide, vincristine, procarbazine, and prednisone) followed by two cycles of ABVD (2 + 2). Chemotherapy was followed by 30 Gy IFRT in both arms. The primary end point was freedom from treatment failure (FFTF); secondary end points included progression-free survival (PFS) and treatment-related toxicity.

Results

With a total of 1,528 qualified patients included, the 2 + 2 regimen demonstrated superior FFTF compared with four cycles of ABVD (P < .001; hazard ratio, 0.44; 95% CI, 0.30 to 0.66), with a difference of 7.2% at 5 years (95% CI, 3.8 to 10.5). The difference in 5-year PFS was 6.2% (95% CI, 3.0% to 9.5%). There was more acute toxicity associated with 2 + 2 than with ABVD, but there were no overall differences in treatment-related mortality or secondary malignancies.

Conclusion

Intensified chemotherapy with two cycles of BEACOPP escalated followed by two cycles of ABVD followed by IFRT significantly improves tumor control in patients with early unfavorable HL.

Dosimetric and clinical outcomes of involved-field intensity-modulated radiotherapy after chemotherapy for early-stage Hodgkin's lymphoma with mediastinal involvement

PURPOSE

To evaluate the dosimetric and clinical outcomes of involved-field intensity-modulated radiotherapy (IF-IMRT) for patients with early-stage Hodgkin's lymphoma (HL) with mediastinal involvement.

METHODS AND MATERIALS

Fifty-two patients with early-stage HL that involved the mediastinum were reviewed. Eight patients had Stage I disease, and 44 patients had Stage II disease. Twenty-three patients (44%) presented with a bulky mediastinum, whereas 42 patients (81%) had involvement of both the mediastinum and either cervical or axillary nodes. All patients received combination chemotherapy followed by IF-IMRT. The prescribed radiation dose was 30-40 Gy. The dose-volume histograms of the target volume and critical normal structures were evaluated.

RESULTS

The median mean dose to the primary involved regions (planning target volume, PTV1) and boost area (PTV2) was 37.5 Gy and 42.1 Gy, respectively. Only 0.4% and 1.3% of the PTV1 and 0.1% and 0.5% of the PTV2 received less than 90% and 95% of the prescribed dose, indicating excellent PTV coverage. The median mean lung dose and V20 to the lungs were 13.8 Gy and 25.9%, respectively. The 3-year overall survival, local control, and progression-free survival rates were 100%, 97.9%, and 96%, respectively. No Grade 4 or 5 acute or late toxicities were reported.

CONCLUSIONS

Despite the large target volume, IF-IMRT gave excellent dose coverage and a favorable prognosis, with mild toxicity in patients with early-stage mediastinal HL.

The important role of radiation therapy in early-stage diffuse large B-cell lymphoma: time to review the evidence once again

Diffuse large B-cell lymphoma (DLBCL) is the most common subtype of non-Hodgkin's lymphoma in the USA, and approximately one-third of patients present with early stage, localized disease. While significant controversy still exists regarding the appropriate management of these patients, the overwhelming evidence from a wide range of studies over the last 40 years points to the superior efficacy of combined-modality therapy for this disease. The current standard of care for the vast majority of early-stage DLBCL cases now involves a combination of chemotherapy, immunotherapy and consolidation radiotherapy. Using this multimodality approach, very high rates of local control can be achieved, which will translate into significant survival benefits for patients with localized disease. The use of intensive immunochemotherapy without radiation therapy requires formal testing and validation in a randomized clinical trial before it can be used as an alternative treatment regimen for early-stage DLBCL. In this article, we discuss the results of the key randomized trials, critical retrospective studies and recent clinical trials, which collectively address the important role of radiotherapy in the treatment of early-stage DLBCL.

Risk of developing cardiovascular disease after involved node radiotherapy versus mantle field for Hodgkin lymphoma

PURPOSE

Hodgkin lymphoma (HL) survivors are known to have increased cardiac mortality and morbidity. The risk of developing cardiovascular disease after involved node radiotherapy (INRT) is currently unresolved, inasmuch as present clinical data are derived from patients treated with the outdated mantle field (MF) technique.

METHODS AND MATERIALS

We included all adolescents and young adults with supradiaphragmatic, clinical Stage I-II HL treated at our institution from 2006 to 2010 (29 patients). All patients were treated with chemotherapy and INRT to 30 to 36 Gy. We then simulated a MF plan for each patient with a prescribed dose of 36 Gy. A logistic dose-response curve for the 25-year absolute excess risk of cardiovascular disease was derived and applied to each patient using the individual dose-volume histograms.

RESULTS

The mean doses to the heart, four heart valves, and coronary arteries were significantly lower for INRT than for MF treatment. However, the range in doses with INRT treatment was substantial, and for a subgroup of patients, with lymphoma below the fourth thoracic vertebrae, we estimated a 25-year absolute excess risk of any cardiac event of as much as 5.1%.

CONCLUSIONS

Our study demonstrates a potential for individualizing treatment by selecting the patients for whom INRT provides sufficient cardiac protection for current technology; and a subgroup of patients, who still receive high cardiac doses, who would benefit from more advanced radiation technique.

Fertility and gonadal function in female survivors after treatment of early unfavorable Hodgkin lymphoma (HL) within the German Hodgkin Study Group HD14 trial

BACKGROUND

In the HD14 trial, 2×BEACOPPescalated+2×ABVD (2+2) has improved the primary outcome. Compared with 4×ABVD, this benefit might be compromised by more infertility in women. Therefore, we analyzed gonadal function and fertility.

PATIENTS AND METHODS

Women≤45 years in ongoing remission at least 1 year after therapy were included. Hormone parameters, menopausal symptoms, measures to preserve fertility, menstrual cycle, pregnancies, and offspring were evaluated.

RESULTS

Three hundred and thirty one of 579 women addressed participated (57.2%) and 263 per-protocol treated patients qualified (A=ABVD: 137, B=2+2: 126, mean time after therapy 42 and 43 months, respectively). Regular menstrual cycle after treatment (A: 87%, B: 83%) and time to recovery (≤12 months) were not different. Follicle-stimulating hormone and anti-Muellerian hormone were significantly better in arm A. However, pregnancies after therapy favored arm B (A: 15%, B: 26%, P=0.043) and motherhood rates were equivalent to the German normal population. Multivariate analysis revealed prophylactic use of gonadotropin-releasing hormone (GnRH) analogues as highly significant prognostic factor for preservation of fertility (odds ratio=12.87, P=0.001). Severe menopausal symptoms were frequent in women≥30 years (A: 21%, B: 25%).

CONCLUSIONS

Hormonal levels after 2+2 indicate a reduced ovarian reserve. However, 2+2 in combination with GnRH analogues does not compromise fertility within the evaluated observation time.

Current status of autologous stem cell transplantation in relapsed and refractory Hodgkin's lymphoma

Despite the relatively high long-term disease-free survival (DFS) rate for patients with Hodgkin lymphoma (HL) with modern combination chemotherapy or combined modality regimens, ∼20% of patients die from progressive or relapsed disease. The standard treatment for relapsed and primary refractory HL is salvage chemotherapy followed by high-dose chemotherapy and autologous stem cell transplantation (ASCT), which has shown a 5-year progression-free survival rate of ∼50%-60%. Recent developments in a number of diagnostic and therapeutic modalities have begun to improve these results. Functional imaging, refinement of clinical prognostic factors, and development of novel biomarkers have improved the predictive algorithms, allowing better patient selection and timing for ASCT. In addition, these algorithms have begun to identify a group of patients who are candidates for more aggressive treatment beyond standard ASCT. Novel salvage regimens may potentially improve the rate of complete remission prior to ASCT, and the use of maintenance therapy after ASCT has become a subject of current investigation. We present a summary of developments in each of these areas.

Positron emission tomography/computed tomography surveillance in patients with Hodgkin lymphoma in first remission has a low positive predictive value and high costs

BACKGROUND

The value of performing post-therapy routine surveillance imaging in patients with Hodgkin lymphoma is controversial. This study evaluates the utility of positron emission tomography/computed tomography using 2-[18F]fluoro-2-deoxyglucose for this purpose and in situations with suspected lymphoma relapse.

DESIGN AND METHODS

We conducted a multicenter retrospective study. Patients with newly diagnosed Hodgkin lymphoma achieving at least a partial remission on first-line therapy were eligible if they received positron emission tomography/computed tomography surveillance during follow-up. Two types of imaging surveillance were analyzed: "routine" when patients showed no signs of relapse at referral to positron emission tomography/computed tomography, and "clinically indicated" when recurrence was suspected.

RESULTS

A total of 211 routine and 88 clinically indicated positron emission tomography/computed tomography studies were performed in 161 patients. In ten of 22 patients with recurrence of Hodgkin lymphoma, routine imaging surveillance was the primary tool for the diagnosis of the relapse. Extranodal disease, interim positron emission tomography-positive lesions and positron emission tomography activity at response evaluation were all associated with a positron emission tomography/computed tomography-diagnosed preclinical relapse. The true positive rates of routine and clinically indicated imaging were 5% and 13%, respectively (P = 0.02). The overall positive predictive value and negative predictive value of positron emission tomography/computed tomography were 28% and 100%, respectively. The estimated cost per routine imaging diagnosed relapse was US$ 50,778.

CONCLUSIONS

Negative positron emission tomography/computed tomography reliably rules out a relapse. The high false positive rate is, however, an important limitation and a confirmatory biopsy is mandatory for the diagnosis of a relapse. With no proven survival benefit for patients with a pre-clinically diagnosed relapse, the high costs and low positive predictive value make positron emission tomography/computed tomography unsuitable for routine surveillance of patients with Hodgkin lymphoma.

The role of autologous transplantation in Hodgkin lymphoma

Between 80% and 90% of Hodgkin lymphoma (HL) patients can be cured with up-to-date combined-modality treatments, but patients with disease refractory to first-line therapy and those who relapse after first-line therapy still have a relatively poor prognosis. Dose intensification with stem cell support has been evaluated both to avoid relapses and to cure patients with refractory or relapsed disease. In this review, we focus on the use of high-dose chemotherapy followed by autologous stem cell transplantation (ASCT) in first-line, second-line, and third-line therapy for HL patients. The relevance of salvage therapy before high-dose chemotherapy is discussed, as well as the role of sequential high dose chemotherapy. We also review current evidence for tandem transplantation in high-risk HL patients and ASCT in elderly patients. Finally, we discuss current concepts of ASCT for HL patients and the use of functional imaging and consolidation therapy.

[Intensity-modulated radiotherapy and involved-node concept in patients with Hodgkin lymphoma: experience of the Gustave-Roussy Institute]

PURPOSE

To assess the clinical outcome of the involved-node radiotherapy concept with the use of intensity modulated radiotherapy (IMRT) in patients with localized supradiaphragmatic Hodgkin lymphoma.

PATIENTS AND METHODS

Patients with early-stage supradiaphragmatic Hodgkin lymphoma were treated with chemotherapy prior to irradiation. Radiation treatments were delivered using the involved-node radiotherapy (INRT) concept according to the EORTC guidelines. Intensity modulated radiotherapy was performed free-breathing.

RESULTS

Forty-seven patients with Hodgkin lymphoma (44 patients with primary Hodgkin lymphoma and three patients with recurrent disease) entered the study from January 2003 to December 2010. The median age was 31 years (range 17 to 62). Thirty patients had stage I-IIA, 14 had stage I-IIB disease and three had relapse. Forty-two patients received three to six cycles of adriamycin, bleomycin, vinblastine and dacarbazine (ABVD). The median radiation dose to patients was 36 Gy (range: 20-40). Protection of various organs at risk was satisfactory. The median follow-up was 57.4 months (range: 5.4-94.3). For patients with primary Hodgkin lymphoma, the 5-year survival and 5-year progression-free survival rates were 96% (95% confidence interval: 80-99) and 92% (95% confidence interval: 78-97), respectively. None of the three patients with recurrent disease has relapsed. Recurrences occurred in three patients: one was in-field relapse and two were visceral recurrences. Grade 3 acute lung toxicity (transient pneumonitis) occurred in one case.

CONCLUSION

Our results suggest that patients with localized Hodgkin lymphoma can be safely and efficiently treated using the involved node irradiation concept and intensity modulated irradiation.

Lymphocyte-Depleted Classical Hodgkin's Lymphoma: A Comprehensive Analysis From the German Hodgkin Study Group

Purpose

To investigate the clinical characteristics and treatment outcome of patients with lymphocyte-depleted classical Hodgkin's lymphoma (LDCHL) compared with other histologic subtypes of Hodgkin's lymphoma (HL).

Patients and Methods

From a total of 12,155 evaluable patients with biopsy-proven HL treated within the German Hodgkin Study Group trials HD4 to HD15, 10,019 patients underwent central expert pathology review. Eighty-four patients with LDCHL (< 1%) were identified and confirmed. The median follow-up time was 67 months.

Results

Patients with LDCHL, compared with patients with other histologic subtypes, presented more often with advanced disease (74% v 42%, respectively; P < .001) and “B” symptoms (76% v 41%, respectively; P < .001). Other risk factors were also more frequent in patients with LDCHL. Complete remission or unconfirmed complete remission was achieved in 82% of patients with LDCHL compared with 93% of patients with other HL subtypes (P < .001), and more patients with LDCHL had progressive disease. At 5 years, progression-free survival (PFS) and overall survival (OS) were significantly lower in patients with LDCHL compared with patients with other HL subtypes (PFS, 71% v 85%, respectively; P < .001; OS, 83% v 92%, respectively; P = .0018). However, when analyzing the subgroup of patients who underwent treatment with intensified or dose-dense bleomycin, etoposide, doxorubicin, cyclophosphamide, vincristine, procarbazine, and prednisone, patients with LDCHL (n = 39) had similar outcomes when compared with patients with other subtypes of HL (n = 3,564; P = .61).

Conclusion

LDCHL has a different pattern from other HL subtypes with more clinical risk factors at initial diagnosis and significantly poorer prognosis. Patients with LDCHL should be treated with modern dose-intense treatment strategies.

Annual clinical updates in hematological malignancies: a continuing medical education series. Hodgkin lymphoma: 2011 update on diagnosis, risk-stratification, and management

DISEASE OVERVIEW

Hodgkin lymphoma (HL) is an uncommon B-cell lymphoid malignancy affecting 8,500 new patients annually and representing approximately 11% of all lymphomas in the United States.

DIAGNOSIS

HL is composed of two distinct disease entities; the more commonly diagnosed classical HL and the rare nodular lymphocyte predominant HL. Nodular sclerosis, mixed cellularity, lymphocyte depletion, and lymphocyte-rich HL are subgroups under the designation of classical HL.

RISK STRATIFICATION

An accurate assessment of the stage of disease in patients with HL is critical for the selection of the appropriate therapy. Prognostic models that identify patients at low or high risk for recurrence are used to optimize therapy for patients with limited or advanced stage disease.

RISK-ADAPTED THERAPY

Initial therapy for HL patients is based on the histology of the disease, the anatomical stage, and the presence of poor prognostic features. Patients with early stage disease are treated with combined modality strategies using abbreviated courses of combination chemotherapy followed by involved-field radiation therapy, while those with advanced stage disease receive a longer course of chemotherapy often without radiation therapy.

MANAGEMENT OF RELAPSED/REFRACTORY DISEASE

High-dose chemotherapy (HDCT) followed by an autologous stem-cell transplant (ASCT) is the standard of care for most patients who relapse following initial therapy. For patients who fail HDCT with ASCT, palliative chemotherapy, nonmyeloablative allogeneic transplant, or participation in a clinical trial should be considered.

MiR-17/106b seed family regulates p21 in Hodgkin's lymphoma

Hodgkin's lymphoma (HL) is a B cell-derived lymphoma characterized by a minority of malignant Hodgkin Reed-Sternberg (HRS) cells that have lost their normal B cell phenotype. Alterations in the cell cycle and apoptosis pathways might contribute to their resistance to apoptosis and sustained cell cycle progression. A key player in both cell cycle arrest and apoptosis is CDKN1A, encoding p21$^{{\rm{waf/cip1}}}$ (p21). P21 is regulated by p53 and can function as a cell cycle inhibitor when in the nucleus or as an apoptosis inhibitor when localized in the cytoplasm. We observed expression of p53, p21 and p-p21 in a variable number of HRS cells in 24 of 40 cases. Expression of miR-17 and miR-106a was detected in HRS cells of 10 HL cases. MiR-17/106b seed family members, CDKN1A RNA and p21 protein levels were variable in HL cell lines. We showed effective targeting of the CDKN1A 3' UTR by miR-17/106b in HL cell lines in a luciferase reporter assay and up-regulation of p21 protein levels upon anti-miR-17 treatment of KM-H2 cells. Functional studies indicated a p21-mediated G(1) arrest after miR-17/106b down-regulation in KM-H2, whereas no G(1) arrest was observed for U-HO1 and L428. This difference could not be explained by differences in the 3' UTR, the cellular location of p21 or expression variation during cell cycle progression. A strong correlation was observed for the miR-17/106b:CDKN1A ratio and the responsiveness to miR-17 inhibition, ie a low ratio in KM-H2 and an extremely high ratio in the two unresponsive HL cell lines. In conclusion, we show that miR-17/106b regulates p21 protein levels in HL and that the effect of miR-17/106b-mediated inhibition depends on the miRNA : target gene ratio. Thus, in HL high miR-17/106b expression contributes to a dysfunctional p53 pathway and thereby also to the malignant phenotype.

Chemotherapy only for localized Hodgkin lymphoma

Radiation therapy (RT) alone and more recently in combination with chemotherapy (combined modality therapy; CMT) has been the cornerstone of curative treatment for early-stage Hodgkin lymphoma (HL) for over 40 years. Because of increasing awareness of the late morbidity and mortality associated with RT, recent treatment regimens have attempted to limit its use. Chemotherapy only has been demonstrated to be a treatment option for most patients with localized HL. Current clinical trials have targeted subgroups of such patients who may be at an increased risk of recurrence for the addition of limited RT to chemotherapy.

Comparison of chemotherapy including escalated BEACOPP versus chemotherapy including ABVD for patients with early unfavourable or advanced stage Hodgkin lymphoma

BACKGROUND

There are two different international standards for the treatment of early unfavourable and advanced stage Hodgkin lymphoma (HL): chemotherapy with escalated BEACOPP (bleomycin/etoposide/doxorubicin/cyclophosphamide/vincristine/procarbazine/prednisone) regimen and chemotherapy with ABVD (doxorubicin/bleomycin/vinblastine/dacarbazine) regimen.

OBJECTIVES

To provide an evidence-based answer regarding the advantages and disadvantages of chemotherapy including escalated BEACOPP compared to chemotherapy including ABVD.

SEARCH STRATEGY

We searched for randomised controlled trials in MEDLINE, CENTRAL and conference proceedings (January 1985 to November 2010) and EMBASE (1985 to November 2008).

SELECTION CRITERIA

We included randomised controlled trials examining chemotherapy including at least two cycles of escalated BEACOPP regimens compared to chemotherapy including at least four cycles of ABVD regimens as first-line treatment for patients with early unfavourable stage or advanced stage HL.

DATA COLLECTION AND ANALYSIS

Effect measures used were hazard ratios (HR) for overall survival (OS), progression-free survival (PFS) and freedom from first progression. Relative risks were used to analyse complete response rate, treatment-related mortality and adverse events. Two independent review authors extracted data and assessed quality of trials.

MAIN RESULTS

A total of 790 records were screened. Five eligible trials (four published, one ongoing), were identified. These trials included only adult patients (16 to 60 years of age). Four trials with 2868 patients were included in the meta-analyses: the HD9 and HD14 trials from Germany, the HD2000 and GSM-HD trials from Italy. All trials reported results for PFS and OS. PFS was statistically significantly longer for escalated BEACOPP: HR was 0.53 (95% confidence interval (CI) 0.44 to 0.64, I(2) = 0%). There was no statistically significant difference in OS between the comparators: HR was 0.80 (95% CI 0.59 to 1.09, I(2) = 0%). Three trials reported adverse events: the escalated BEACOPP regimens caused statistically significantly more haematological toxicities WHO grade III or IV (anaemia P < 0.00001, neutropenia P = 0.007, thrombocytopenia P < 0.00001), infections (P < 0.00001)) and occurrence of myeloid dysplastic syndrome (MDS) or acute myeloid leukemia (AML) (P = 0.05). There were no differences between both regimens for secondary malignancies, treatment-related mortality or infertility.

AUTHORS' CONCLUSIONS

This meta-analysis showed that adult patients between 16 and 60 years of age with early unfavourable or advanced stage HL benefited from chemotherapy including escalated BEACOPP regarding PFS, but there was no significant difference in OS. Longer follow-up and the inclusion of the EORTC 20012 trial will lead to a more definitive answer with respect to OS.

Current concepts and controversies in the management of early stage Hodgkin lymphoma

Over the past three decades, due to the recognition of late effects related to high-dose extended field radiotherapy and heavy alkylator chemotherapy, combined modality therapy with abbreviated chemotherapy and limited field radiotherapy has emerged as the standard of care for early stage Hodgkin lymphoma, with cure rates in excess of 80%. Currently, however, controversy remains over identifying the most appropriate criteria to risk-stratify patients with early stage disease, so that those with a favorable prognosis receive limited treatment without compromising cure rates and those with unfavorable risk receive more intensified therapy. The optimal risk stratification system remains unclear, with variable definitions of favorable and unfavorable disease used by research groups in North America and Europe. Thus, comparison of clinical trial results has been challenging, and additional controversies persist regarding optimal chemotherapy regimens, duration of therapy, and the role of radiotherapy. Investigations are ongoing to assess the potential of functional imaging and biomarkers as tools for risk stratification. The collective goal is to further refine current stratification strategies to allow for an individualized, risk-adapted treatment approach that minimizes long-term late effects without compromising high cure rates.

Doxorubicin, vinblastine, and gemcitabine (CALGB 50203) for stage I/II nonbulky Hodgkin lymphoma: pretreatment prognostic factors and interim PET

To reduce doxorubicin, bleomycin, vinblastine and dacarbazine toxicity, the Cancer and Leukemia Group B conducted a phase 2 trial of doxorubicin, vinblastine, and gemcitabine for newly diagnosed, nonbulky stages I and II Hodgkin lymphoma. Ninety-nine assessable patients received 6 cycles of doxorubicin 25 mg/m(2), vinblastine 6 mg/m(2), and gemcitabine 800 mg/m(2) (1000 mg/m(2) in first 6) on days 1 and 15 every 28 days. Computed tomography (CT) and positron emission tomography (PET) were performed before and after 2 and 6 cycles. Complete remission (CR)/CR unconfirmed was achieved in 72 of 99 patients (72.7%) and partial remission in 24 of 99 patients (24.2%). The CR rate was 81% when using PET criteria. Two patients have died of Hodgkin lymphoma progression. Median follow-up for nonprogressing patients is 3.3 years. The progression-free survival (PFS) at 3 years was 77% (95% confidence interval, 68%-84%). The relapse rate was less than 10% for patients with favorable prognostic factors. The 2-year PFS for cycle 2 PET-negative and -positive patients was 88% and 54%, respectively (P = .0009), compared with 89% and 27% for cycle 6 PET-negative and -positive patients (P = .0001). Although the CR rate and PFS were lower than anticipated, patients with favorable prognostic features had a low rate of relapse. Cycle 2 PET and cycle 6 PET were predictive of PFS.

Hodgkin's lymphoma therapy: past, present, and future

IMPORTANCE OF THE FIELD

The treatment of Hodgkin's lymphoma (HL) with the use of radiotherapy and systemic chemotherapy has been one of the success stories of modern oncology. HL therapy has been the paradigm for the systematic evaluation of different curative modalities, resulting in cure for the majority of patients. The current focus is on designing initial therapeutic strategies that retain efficacy and minimize long-term toxicity. Appropriate use of pathologic, clinical, biologic and radiologic prognostic factors in identification of aggressive HL is paramount in designing a successful therapeutic strategy.

AREAS COVERED IN THIS REVIEW

This review addresses the current and future use of prognostic tools, including PET scanning and other biomarkers, in identifying patients with aggressive HL, with reference to publications from the last two decades. The current standard approaches with the use of combined modality therapy and systemic chemotherapy as well as the promising role of future response-adapted strategies is reviewed.

WHAT THE READER WILL GAIN

The reader will obtain a comprehensive review of risk assessment strategies as well as current and investigational therapeutic approaches in the management of HL.

TAKE HOME MESSAGE

In HL, appropriate utilization of risk assessment strategies is required to maximize therapeutic outcomes while minimizing toxicity, especially long-term toxicity. Response-adapted therapy utilizing PET has the potential to profoundly improve the therapeutic landscape in HL.

Interim FDG-PET Scan in Hodgkin's Lymphoma: Hopes and Caveats

FDG-PET has recently emerged as an important tool for the management of Hodgkins lymphoma. Although its use for initial staging and response evaluation at the end of treatment is well established, the place of interim PET for response assessment and subsequent treatment tailoring is still quite controversial. The use of interim PET after a few cycles of chemotherapy may allow treatment reduction for good responders, leading to lesser treatment toxicities as well as early treatment adaptation for bad responders with a potential higher chance for cure. Interpretation of interim PET is a rapidly moving field. Actually, visual interpretation is preferred over quantitative interpretation in this situation. The notion of minimal residual uptake emerged for faint persisting FDG uptake, but has evolved during the recent years. Guidelines using mediastinum and liver as references have been proposed at the expert meeting in Deauville 2009. Actually, several trials are ongoing both for localised and advanced disease to evaluate the FDG-PET potential for early treatment monitoring and tailoring. Until the results of these prospective randomized trials become available, treatment changes according to the interim PET results should remain inappropriate and limited to well-conducted clinical trials.