Progressive kidney failure in chronic myelomonocytic leukaemia: don't forget lysozyme damage.

Kidney failure is common in haematologic malignancies. However, the nephrotoxic effect of lysozyme is seldom recognized. We present a 78-year-old male with chronic myelomonocytic leukaemia who developed progressive kidney failure due to increased production of lysozyme.

A 20-year population-based study on the epidemiology, clinical features, treatment, and outcome of nodular lymphocyte predominant Hodgkin lymphoma.

Nodular lymphocyte predominant Hodgkin lymphoma (NLPHL) is a subtype of Hodgkin lymphoma characterized by a unique clinical and histological presentation. Because of the rare nature of this disease, few large-scale studies are available. We conducted a cohort study in which patients were identified in the Netherlands Cancer Registry in the Southeast of the Netherlands between 1990 and 2010. Of these patients, we collected all clinical characteristics and re-reviewed pathologic material to confirm NLPHL diagnosis. Seventy-three histologically confirmed cases of NLPHL were analyzed with a median follow-up of 65 months (range 4-257 months). Median age at diagnosis was 43 years (range 1-87); 84.9 % of the patients were male; B symptoms were present in 5.5 %; and stage I/II disease was most common (75.4 %). Patients were primarily treated with radiotherapy (50.7 %), chemotherapy (26 %), combined modality (radiotherapy and chemotherapy) (11 %), or surgical excision with careful watch-and-wait (12.3 %). Relapses occurred in seven patients (9.6 %) after a median of 26 months (21-74 months). Six patients (8.2 %) developed histologic transformation to large cell lymphoma. Five patients (6.8 %) died during follow-up due to progression of NLPHL (n = 1), histologic transformation (n = 2) and intercurrent deaths (n = 2). The estimated 10-year overall survival was 94.0 % and the 10-year progression-free survival 75.8 %. Our study confirms the distinct characteristics of NLPHL with a relatively good long-term prognosis. It may be possible to reduce treatment intensity in early stage NLPHL without affecting long-term outcome.

Cryopreservation, semen use and the likelihood of fatherhood in male Hodgkin lymphoma survivors: an EORTC-GELA Lymphoma Group cohort study.

STUDY QUESTION: How does the successful cryopreservation of semen affect the odds of post-treatment fatherhood among Hodgkin lymphoma (HL) survivors? SUMMARY ANSWER: Among 334 survivors who wanted to have children, the availability of cryopreserved semen doubled the odds of post-treatment fatherhood. WHAT IS KNOWN ALREADY: Cryopreservation of semen is the easiest, safest and most accessible way to safeguard fertility in male patients facing cancer treatment. Little is known about what proportion of patients achieve successful semen cryopreservation. To our knowledge, neither the factors which influence the occurrence of semen cryopreservation nor the rates of fatherhood after semen has been cryopreserved have been analysed before. STUDY DESIGN, SIZE, DURATION: This is a cohort study with nested case-control analyses of consecutive Hodgkin survivors treated between 1974 and 2004 in multi-centre randomized controlled trials. A written questionnaire was developed and sent to 1849 male survivors. PARTICIPANTS/MATERIALS, SETTING, METHODS: Nine hundred and two survivors provided analysable answers. The median age at treatment was 31 years. The median follow-up after cryopreservation was 13 years (range 5-36). MAIN RESULTS AND THE ROLE OF CHANCE: Three hundred and sixty-three out of 902 men (40%) cryopreserved semen before the start of potentially gonadotoxic treatment. The likelihood of semen cryopreservation was influenced by age, treatment period, disease stage, treatment modality and education level. Seventy eight of 363 men (21%) used their cryopreserved semen. Men treated between 1994 and 2004 had significantly lower odds of cryopreserved semen use compared with those treated earlier, whereas alkylating or second-line (chemo)therapy significantly increased the odds of use; no other influencing factors were identified. We found an adjusted odds ratio of 2.03 (95% confidence interval 1.11-3.73, P = 0.02) for post-treatment fatherhood if semen cryopreservation was performed. Forty-eight out of 258 men (19%) who had children after HL treatment became a father using cryopreserved semen. LIMITATIONS, REASONS FOR CAUTION: Data came from questionnaires and so this study potentially suffers from response bias. We could not perform an analysis with correction for duration of follow-up or provide an actuarial use rate due to lack of dates of semen utilization. We do not have detailed information on either the techniques used in cryopreserved semen utilization or the number of cycles needed. STUDY FUNDING/COMPETING INTERESTS: Lance Armstrong Foundation, Dutch Cancer Foundation, René Vogels Stichting, no competing interests.

Centralised multidisciplinary re-evaluation of diagnostic procedures in patients with newly diagnosed Hodgkin lymphoma.

BACKGROUND: Hodgkin Lymphoma (HL) is highly curable when treated accurately. The challenge is to cure patients with the minimal risk of long-term complications. For that, optimal initial diagnostics are required to determine the optimal treatment plan. We offer non-academic hospitals in our Regional Comprehensive Cancer Centre network a centralised review of all diagnostic procedures from patients with newly diagnosed HL. We report our experience on concordances and discrepancies between local findings and central review results. PATIENTS AND METHODS: A haematologist and radiation oncologist at the Hodgkin Radboud University Nijmegen Medical Centre outpatient clinic examined all patients with newly diagnosed HL between February 2006 and May 2010. In a multidisciplinary lymphoma conference, diagnostic information is reviewed and treatment advice formulated. Discordant findings in pathology, staging and therapy were recorded as 'minor', no therapeutic consequences or 'major', adapted therapy advice. RESULTS: Altogether, 125 patients were included. Pathology review showed 86% concordance, with 4% major discordance, mainly nodular lymphocyte predominant sub-type. Revision of initial staging was concordant in 77%; however 15% major discordance of which most were upstaged. This resulted in 19% treatment adaption. CONCLUSION: Our findings highlight the discrepancies in interpretation of diagnostic tests. We advocate centralised review process for all newly diagnosed patients with HL.

Delayed and prolonged coma after acute disulfiram overdose.

We report the case of a 35-year-old man presenting with a delayed and prolonged coma due to an intentional overdose with disulfiram without simultaneous alcohol ingestion. The clinical features--comprising a severe toxic encephalopathy with coma and convulsions, in combination with a quadriparesis outlasting the loss of consciousness--are summarized, and the physiopathology is reviewed.

90-day follow-up of patients treated with Drotrecogin Alfa (activated) for severe sepsis: a Belgian open label study.

INTRODUCTION: Severe sepsis is the major cause of mortality in intensive care units (ICUs). The BOOST study (= B (Belgian) OO (Open Label) ST (Study)) is a Belgian open-label trial designed to pragmatically assess the safety and efficacy of Drotrecogin Alfa (activated) (DAA), the only registered treatment in this indication with favourable ratio benefit/risk. METHODOLOGY: Adult patients with severe sepsis and 2 or more sepsis-induced organ dysfunctions (OD) within the 48-hour period preceding the treatment (DAA at 24 microg/kg/h for 96 hours), were included between January 2003 and October 2003. Platelet count < 30 000/mm3 and increased risk for bleeding were exclusion criteria. Mortality and location were evaluated at 28 and 90 days. RESULTS: Of the 100 included patients, 97 (median age: 66 years; men/women: 57/40) were treated and completed the study. The predominant infection sites were lung (49%) and abdomen (29%) and 35% had had recent surgery. The mean and median numbers of OD were 3.4 and 3.0, respectively, and most patients (80 %; 77/97) had 3 or more organ failures at baseline, predominantly respiratory (95%) and cardiovascular (87%). The mean APACHE II score was 25.3 (range: 6-53). The 28-day mortality rate was 32.0% (90% CI: 24.2-39.7) and increased with the number of OD: from 15% (1.9-28.1) for2 ODs, to 71% (52.4-88.8) for 5 ODs. At day 28, the 66 surviving patients were located in general ward (35%), in the ICU (32%) or at home (30%). The 90-day mortality rate was 42% (90% CI: 34.0-50.5), with most of the survivors (73%) staying at home. Eight serious adverse events, including 4 bleedings, were reported between study days 2 and 5, in 5 patients (5.2%) and led to death in 2 patients (2.1%). CONCLUSION: Despite a higher severity of illness at baseline, this phase IV open-label long-term study in Belgian ICUs shows consistent results with previous studies with DAA. Importantly, most of the surviving patients at day 90 were staying at home.

Immunohistochemical prognostic markers in diffuse large B-cell lymphoma: validation of tissue microarray as a prerequisite for broad clinical applications (a study from the Lunenburg Lymphoma Biomarker Consortium).

BACKGROUND AND AIMS: The results of class prediction and the determination of prognostic markers in diffuse large B-cell lymphoma (DLBCL) have been variably reported. Apart from biological variations, this may be caused by differences in laboratory techniques, scoring definitions and inter- and intra-observer variation. In this study, an international collaboration of clinical lymphoma research groups has concentrated on validation and standardisation of immunohistochemistry of the currently potentially interesting prognostic markers in DLBCL. METHODS: Sections of a tissue microarray with 36 cases of DLBCL were stained in eight laboratories with antibodies to CD20, CD5, bcl-2, bcl-6, CD10, HLA-DR, MUM-1 and Ki-67 according to local methods. The study was performed in two rounds, firstly focused on the evaluation of laboratory staining variation, and secondly on the scoring variation. RESULTS: Different techniques resulted in highly variable results and poor reproducibility for almost all markers. Reproducibility of the nuclear markers was highly sensitive to technical variations, including immunological enhancement techniques (agreements 34%). With elimination of variation due to staining and uniformly agreed on scoring criteria, significant improvement was seen; however less so for bcl-6 and Ki-67 (agreement 53-58%). Absence of internal controls that preclude scoring, significantly influenced the results for CD10 and bcl-6. CONCLUSION: Semi-quantitative immunohistochemistry for subclassification of DLBCL is feasible, but with varying rates of concordance for different markers and only using optimised techniques and strict scoring criteria. These findings may explain the wide variation in prognostic impact reported in the literature. Harmonisation of techniques and centralised consensus review appears mandatory when using immunohistochemical biomarkers for treatment stratification.

A registry of patients treated with drotrecogin alfa (activated) in Belgian intensive care units--an observational study.

BACKGROUND: Drotrecogin alfa (activated) [DrotAA] is the only specific sepsis therapy that has been shown to reduce mortality. The objectives of this study were to document the profile of patients treated with DrotAA in Belgian intensive care units (ICUs), using data from a database established as part of drug reimbursement conditions in Belgium, and to compare the observed hospital mortality of these patients with their expected mortality, calculated using data from non-DrotAA-treated patients from the Belgian section of PROGRESS, a separate, voluntary, international sepsis registry collecting data from patients with severe sepsis. MATERIAL AND METHODS: Data from the non-DrotAA-treated patients in PROGRESS were used to calculate the expected mortality rates for DrotAA-treated patients in the Belgian registry. Using a logistic regression equation, these rates were controlled for age and the presence or absence of organ dysfunction in each of 5 organ systems. The same logistic regression technique was used to control the mortality rates observed in the DrotAA-treated patients from the Belgian registry for age and the presence or absence of each of the 5 organ dysfunctions. Adjusted expected and observed hospital mortality rates could then be compared. RESULTS: There were 436 DrotAA patients in the Belgian registry. Almost all the patients (99.5%) had at least 2 organ failures and the hospital mortality was 51.6%. Two hundred and eighty-six of the patients had enough baseline data to be included in the regression model. Using data from the PROGRESS non-DrotAA patients, the predicted hospital mortality, controlled for age and organ dysfunction, of Belgian registry patients, had they not been treated with DrotAA, was 63.5%. The observed hospital mortality, again controlled for age and organ dysfunction, of the 286 Belgian registry patients was 50.7%, implying an adjusted absolute mortality reduction of 12.8%. CONCLUSIONS: Comparing Belgian reimbursement registry data with those of a voluntary severe sepsis register provides support for the observation that DrotAA reduces mortality rates in severe sepsis and septic shock.

A phase II study of enzastaurin, a protein kinase C beta inhibitor, in patients with relapsed or refractory mantle cell lymphoma.

BACKGROUND: Protein kinase C beta (PKCbeta), a pivotal enzyme in B-cell signaling and survival, is overexpressed in most cases of mantle cell lymphoma (MCL). Activation of PI3K/AKT pathway is involved in pathogenesis of MCL. Enzastaurin, an oral serine/threonine kinase inhibitor, suppresses signaling through PKCbeta/PI3K/AKT pathways, induces apoptosis, reduces proliferation, and suppresses tumor-induced angiogenesis. PATIENTS AND METHODS: Patients with relapsed/refractory MCL, and no more than four regimens of prior therapy, received 500 mg enzastaurin, orally, once daily. RESULTS: Sixty patients, median age 66 years (range 45-85), Eastern Cooperative Oncology Group performance status of zero to two (48% had baseline International Prognostic Index of 3-5), were enrolled. Most patients had prior CHOP-like chemotherapy and/or rituximab (median = 2 regimens). No drug-related deaths occurred. There was one case each of grade 3 anemia, diarrhea, dyspnea, vomiting, hypotension, and syncope. Fatigue was the most common toxicity. Although no objective tumor responses occurred, 22 patients (37%, 95% CI 25% to 49%) were free from progression (FFP) for > or =3 cycles (one cycle = 28 days); 6 of 22 were FFP for >6 months. Two patients remain on treatment and FFP at >23 months. CONCLUSION: Freedom from progression for >6 months in six patients and a favorable toxicity profile with minimal hematological toxicity indicate that enzastaurin warrants evaluation as maintenance therapy and combination chemotherapy in MCL.

Second malignancy risk associated with treatment of Hodgkin's lymphoma: meta-analysis of the randomised trials.

BACKGROUND: Despite several investigations, second malignancy risks (SMR) following radiotherapy alone (RT), chemotherapy alone (CT) and combined chemoradiotherapy (CRT) for Hodgkin's lymphoma (HL) remain controversial. PATIENTS AND METHODS: We sought individual patient data from randomised trials comparing RT versus CRT, CT versus CRT, RT versus CT or involved-field (IF) versus extended-field (EF) RT for untreated HL. Overall SMR (including effects of salvage treatment) were compared using Peto's method. RESULTS: Data for between 53% and 69% of patients were obtained for the four comparisons. (i) RT versus CRT (15 trials, 3343 patients): SMR were lower with CRT than with RT as initial treatment (odds ratio (OR) = 0.78, 95% confidence interval (CI) = 0.62-0.98 and P = 0.03). (ii) CT versus CRT (16 trials, 2861 patients): SMR were marginally higher with CRT than with CT as initial treatment (OR = 1.38, CI 1.00-1.89 and P = 0.05). (iii) IF-RT versus EF-RT (19 trials, 3221 patients): no significant difference in SMR (P = 0.28) although more breast cancers occurred with EF-RT (P = 0.04 and OR = 3.25). CONCLUSIONS: Administration of CT in addition to RT as initial therapy for HL decreases overall SMR by reducing relapse and need for salvage therapy. Administration of RT additional to CT marginally increases overall SMR in advanced stages. Breast cancer risk (but not SMR in general) was substantially higher after EF-RT. Caution is needed in applying these findings to current therapies.

Extranodal marginal zone (MALT) lymphoma in common variable immunodeficiency.

We describe two patients with common variable immunodeficiency (CVID) who developed extranodal marginal zone lymphoma (formerly described as mucosa-associated lymphoid tissue lymphoma or MALT lymphoma). One patient, with documented pernicious anaemia and chronic atrophic gastritis with metaplasia, developed a Helicobacter pylori-positive extranodal marginal zone lymphoma in the stomach. Three triple regimens of antibiotics were necessary to eliminate the H. pylori, after which the lymphoma completely regressed. Patient B had an H. pylori-negative extranodal marginal zone lymphoma of the parotid gland, which remarkably regressed after treatment with clarithromycin. Reviewing the literature, we found eight cases of extranodal marginal zone lymphoma complicating CVID, but probably many more cases labelled as non-Hodgkin's lymphoma are hidden in the literature. Until more data are available on the predictive value of noninvasive screening for pathology of the stomach, we recommend endoscopy to assess the gastric status in CVID patients in order to detect these malignancies at an early stage. Elimination of H. pylori infection is the treatment of choice in Helicobacter-positive extranodal marginal zone lymphoma. The possibility of elimination failure, most probably due to frequent and prolonged exposure to antibiotics in this patient group, should be taken into account. Treatment with antibiotics in Helicobacter-negative extranodal marginal zone lymphoma must be considered.

Short intensive sequential therapy followed by autologous stem cell transplantation in adult Burkitt, Burkitt-like and lymphoblastic lymphoma.

The feasibility and efficacy of up-front high-dose sequential chemotherapy followed by autologous stem cell transplantation (ASCT) in previously untreated adults (median age 33 years; range 15-64) with Burkitt lymphoma (BL), Burkitt-like lymphoma (BLL) or lymphoblastic lymphoma (LyLy), both without central nervous system or extensive bone marrow involvement was investigated in a multicenter phase II study. Treatment consisted of two sequential high-dose chemotherapy induction courses incorporating prednisone, cyclophosphamide, doxorubicin, etoposide and mitoxantrone, without high-dose methotrexate or high-dose cytarabine. Patients with at least PR went on with BEAM and ASCT. Protocol treatment was completed by 23/27 (85%) BL/BLL and 13/15 (87%) LyLy patients. Median treatment duration until BEAM was 70 (range: 50-116) days. No toxic deaths occurred. Response to treatment was complete response (CR) 81% and partial response (PR) 11% for BL/BLL, CR 73% and PR 20% for LyLy. At a median follow-up of 61 months of patients still alive, six BL/BLL and eight LyLy patients have died. The actuarial 5-year overall and event-free survival estimates are 81 and 73% for BL/BLL vs 46 and 40% for LyLy patients. In conclusion, this short up-front high-dose sequential chemotherapy regimen, followed by ASCT is highly effective in adults with BL/BLL with limited bone marrow involvement, but less so in patients with LyLy.

A rapid and simple determination of A77 1726 in human serum by high-performance liquid chromatography and its application for optimization of leflunomide therapy.

Leflunomide is a disease-modifying antirheumatic drug, which is bioactivated by formation of A77 1726. In this study a rapid and simple quantitative assay using a reversed phase HPLC-UV method is validated for detection of A77 1726 in human serum. The HPLC-UV method uses a mobile phase consisting of methanol and a KH2PO4-buffer (45 mM, pH = 3) (50:50,v/v), at a flow rate of 1 mL/min. A77 1726 is detected by UV-absorption at 295 nm with a retention time of 8.9 min. Demoxepam is used as internal standard. Validation showed lower and upper limits of quantitation of 0.5 and 100 mg/L, respectively. The assay was linear over the concentration range of 0.5-100 mg/L (r2 > 0.999). Intra- and inter-day precision showed coefficients of variation within 15% over the complete concentration range; accuracy was within 8%. Commonly prescribed drugs to treat rheumatoid arthritis like disease-modifying antirheumatic drugs, analgesics and corticosteroids, and their main metabolites, are separated from A77 1726 with a resolution >2. Serum levels of A77 1726 in 37 patients on leflunomide therapy were determined using this HPLC-UV method. Measured serum A77 1726 serum concentrations in patient samples showed large variability with a range of 3-176 mg/L.

Long-term efficacy of the CHVmP/BV regimen used for aggressive non-Hodgkin's lymphoma in three randomised EORTC trials.

We analysed data from 936 newly-diagnosed patients with advanced, aggressive non-Hodgkin's lymphoma (NHL) treated in three randomised European Organisation for Research and Treatment of Cancer (EORTC) trials performed between 1980 and 1999 (median follow-up of 8.7 (0.2-20.4) years). The CHOP-like regimen CHVmP/BV (cyclophosphamide, doxorubicin, teniposide and prednisone with bleomycin and vincristine at mid-interval), was compared with CHVmP (CHVmP/BV without bleomycin and vincristine), ProMACE-MOPP (methotrexate, doxorubicin, cyclophosphamide, etoposide, mechlorethamide, vincristine, procarbazine and prednisone) and CHVmp/BV with additional, autologous stem-cell transplantation, respectively. Overall, treatment with CHVmP/BV resulted in a better long-term outcome with 63% complete responses being observed and an overall survival (OS) of 59 and 43% at 5 and 10 years, respectively. Remarkably, OS after CHVmP/BV improved across the trials, even after stratifying for the International Prognostic Index (IPI). This finding could not be directly related to better salvage treatments during the last decade. Selection bias appears to be responsible: stepwise corrections for small differences in inclusion criteria eliminated the difference in OS, especially when histological subgroups were studied. This systemic review underlines the difficulties encountered in retrospective sub-set analyses and the biases that can be introduced when recent studies are compared with older ones.

Graft-versus-lymphoma effect of donor lymphocyte infusion in indolent lymphomas relapsed after allogeneic stem cell transplantation.

Donor lymphocyte infusions (DLI) are used to treat relapsed haematological diseases after allogeneic stem cell transplantation (SCT). We treated seven patients with DLI for indolent non-Hodgkin's lymphoma relapsed after SCT. In available blood and bone marrow samples, lymphoma cells were analysed by real-time quantitative polymerase chain reaction of t(14;18)-positive cells in follicular lymphoma, and by immunophenotyping in small lymphocytic lymphoma. Before DLI, three patients were treated with chemo- and/or radiotherapy, and one with rituximab. Evaluable responses to pre-DLI therapy were stable disease in one and partial remission (PR) in two patients. Six patients responded to DLI (complete remission (CR) in four and PR in two). After DLI, acute graft-versus-host disease (GVHD) occurred in 3/6 patients, classified as grade 2, whereas only limited chronic GVHD was seen (n=5). The four continuous CR are lasting for median 65+ (43-89) months. In the remaining patient, not responding to DLI, progressive disease was seen later on; chemotherapy followed by another DLI resulted in CR. In three cases, clinical responses to DLI could be substantiated by molecular or immunophenotypic analysis of lymphoma cells. We conclude that DLI is effective for treatment of indolent lymphoma relapsing after SCT.

Dynamics of circulating t(14;18)-positive cells during first-line and subsequent lines of treatment in follicular lymphoma.

In follicular lymphoma the t(14;18) might be useful as a tumor marker in predicting the quality of the response to treatment. We investigated whether analyzing numbers of t(14;18)-positive cells in peripheral blood correlated with remission status in individual patients receiving a variety of treatments. Numbers of circulating t(14;18)-positive cells were determined by real-time polymerase chain reaction (PCR) technique. Disease parameters and response to treatment were related to the pre- and post-treatment numbers of circulating t(14;18)-positive cells for 53 follicular lymphoma patients. In these 53 patients, 70 treatment episodes were investigated. A content of more than 328 t(14;18)-positive cells per 75,000 cells prior to therapy correlated with the more advanced stage IV disease ( P=0.01), bone marrow involvement ( P<0.01), and overt leukemic lymphoma ( P=0.04). Therapy episodes that cleared circulation from t(14;18)-positive cells with more than one log resulted in a significantly longer progression-free survival than treatment episodes with less than one log decline (26 versus 12 months, respectively) ( P<0.01). After first-line treatment episodes, numbers of circulating t(14;18)-positive cells declined in fairly all cases, irrespective of the clinical response. However, for second or later lines of treatment, declining numbers of lymphoma cells correlated with a clinical remission, whereas increasing numbers of lymphoma cells were associated with clinically stable or progressive disease. From this, we conclude that quantitation of circulating t(14;18)-positive cells in peripheral blood is of only limited clinical significance in predicting treatment efficacy for the individual follicular lymphoma patient.

Early response to chemotherapy: a surrogate for final outcome of Hodgkin's disease patients that should influence initial treatment length and intensity?

BACKGROUND: Early adjustment of treatment may benefit the patient. In order to guide treatment adjustment, use of early response (ER) or early complete response (ECR), judged after the few initial cycles of chemotherapy, is common in pediatric and also adult Hodgkin's and non-Hodgkin's studies. Paradoxically, almost no data support this strategy. PATIENTS AND METHODS: The influence of ECR on outcome was evaluated in three series of advanced Hodgkin's disease (HD), leading to a series of questions. RESULTS: The 1982 EORTC study assessed prospectively the time frame needed to reach an apparent complete response (CR) through repeated tumor measurements. In patients assessed at mid-treatment before the fifth cycle, both 15 year freedom from progression (FFP) and overall survival (OS) were superior in ECR patients compared with other patients continued on the same treatment (61% versus 37%; P < 0.001). A series of questions arise from these observations. Question 1: is the shortening of treatment detrimental? In a randomized Swedish trial, in one arm treatment was shortened in patients evaluated from the fifth cycle as ECR as compared with the standard eight cycles arm, 10 year cause-specific-survival (CSS) was 53 versus 69% [not significant (ns)]; 10 year OS 49% versus 58% (ns). Conversely, in the EORTC 20884 study, ECR patients given only six cycles did as well as patients entering CR later and, for this reason, given eight cycles (identical 6 year event-free survival 75%). Question 2: is early treatment adaptation in patients who failed to reach ER beneficial? In the French MDH 90 trial, 15% of children failed to reach ECR after four cycles; in these children only, anthracyclines plus alkylating agents were given and the dose of radiotherapy increased, improving the results observed in the previous trial. In the EORTC 20884 study, patients who failed to reach an ECR were switched earlier to involved field RT: their results matched those of ECR patients, at the difference of the previous trial. Question 3: is ER a predicting factor that can be used with any type of treatment? Probably not, based on the German Hodgkin's Lymphoma Study Group trial HD 9: ECR is highly dependent on specific interval from treatment start and on treatment intensity. DISCUSSION: More general questions stem from these results. Question 4: is the definition of ER secured? With conventional imaging, the different methods for response assessment at end treatment also lead to different response rates; the assessment in the middle of treatment itself and the use of newer imaging techniques may further increase the variation. Indeed, question 5 is: is ER a concept based on any biology? Correlation to markers, 99mTc uptake, PET and hematological tolerance might help to pinpoint how and why ER represents a surrogate for final outcome. CONCLUSION: ER is a surrogate for final outcome, reflecting both tumor burden and activity. This predictability may, and possibly should, impact on treatment.