The Italian Multicentric Randomized OPTkIMA Trial on Fixed vs Progressive Intermittent TKI Therapy in CML Elderly Patients: 3-Years of Molecular Response and Quality of Life Monitoring After Completing the Treatment Plan.

BACKGROUND: Intermittent treatment with tyrosine kinase inhibitors (TKIs) is an option for elderly chronic myeloid leukemia (CML) patients who are often candidates for life-long treatment. MATERIALS AND METHODS: The Italian phase III multicentric randomized Optimize TKIs Multiple Approaches (OPTkIMA) study aimed to evaluate if a progressive de-escalation of TKIs is able to maintain the molecular remission (MR)3.0 and to improve Health-Related Quality of Life (HRQoL) in CML elderly patients. RESULTS: A total of 215 patients in stable MR3.0/MR4.0 were randomized to receive an intermittent TKI schedule 1 month ON-1 month OFF for 3 years (FIXED arm; n = 111) vs. a progressive de-escalation TKI dose up to one-third of the starting dose at the 3rd year (PROGRESSIVE arm; n = 104). Two hundred three patients completed the 3rd year of OPTkIMA study. At the last follow-up, MR3.0 loss was 27% vs. 46% (P = .005) in the FIXED vs PROGRESSIVE arm, respectively. None of these patients experienced disease progression. The 3-year probability of maintaining the MR3.0 was 59% vs. 53%, respectively (P = .13). HRQoL globally improved from the baseline to the 3rd year, without any significant difference between the 2 arms. After the 3rd year, the proportion of patients who was address to TKI discontinuation in the 2 arms was 36% (FIXED) vs. 58% (PROGRESSIVE) (P = .03). CONCLUSIONS: The intensification of intermittent TKI therapy is associated with a higher incidence of MR3.0 loss, but those patients who maintain the MR3.0 molecular response at the end of the study have been frequently considered eligible for TFR. The HRQoL generally improved during the de-escalation therapy in both randomization arms.

Determinants of frontline tyrosine kinase inhibitor choice for patients with chronic-phase chronic myeloid leukemia: A study from the Registro Italiano LMC and Campus CML.

BACKGROUND: Imatinib, dasatinib, and nilotinib are tyrosine kinase inhibitors (TKIs) approved in Italy for frontline treatment of chronic-phase chronic myeloid leukemia (CP-CML). The choice of TKI is based on a combined evaluation of the patient's and the disease characteristics. The aim of this study was to analyze the use of frontline TKI therapy in an unselected cohort of Italian patients with CP-CML to correlate the choice with the patient's features. METHODS: A total of 1967 patients with CP-CML diagnosed between 2012 and 2019 at 36 centers throughout Italy were retrospectively evaluated; 1089 patients (55.4%) received imatinib and 878 patients (44.6%) received a second-generation (2G) TKI. RESULTS: Second-generation TKIs were chosen for most patients aged <45 years (69.2%), whereas imatinib was used in 76.7% of patients aged >65 years (p < .001). There was a predominant use of imatinib in intermediate/high European long-term survival risk patients (60.0%/66.0% vs. 49.7% in low-risk patients) and a limited use of 2G-TKIs in patients with comorbidities such as hypertension, diabetes, chronic obstructive pulmonary disease, previous neoplasms, ischemic heart disease, or stroke and in those with >3 concomitant drugs. We observed a greater use of imatinib (61.1%) in patients diagnosed in 2018-2019 compared to 2012-2017 (53.2%; p = .002). In multivariable analysis, factors correlated with imatinib use were age > 65 years, spleen size, the presence of comorbidities, and ≥3 concomitant medications. CONCLUSIONS: This observational study of almost 2000 cases of CML shows that imatinib is the frontline drug of choice in 55% of Italian patients with CP-CML, with 2G-TKIs prevalently used in younger patients and in those with no concomitant clinical conditions. Introduction of the generic formulation in 2018 seems to have fostered imatinib use.

Minimal residual disease-driven treatment intensification with sequential addition of ibrutinib to venetoclax in R/R CLL.

Undetectable measurable residual disease (uMRD) is achievable in patients with chronic lymphocytic leukemia (CLL) with the BCL2-inhibitor venetoclax alone or combined with the Bruton's tyrosine kinase inhibitor ibrutinib. This phase 2, multicenter, MRD-driven study was designed to discontinue treatment upon reaching uMRD4 (<10-4) in patients with relapsed/refractory CLL receiving venetoclax monotherapy or after the addition of ibrutinib. Primary end point of the study was proportion of uMRD4 with venetoclax ± ibrutinib. Secondary end points were overall response rate, partial response, complete response, progression-free survival, duration of response, overall survival, and safety of venetoclax ± ibrutinib. Patients with uMRD4 at Cycle 12 Day 1 discontinued venetoclax. MRD+ patients added ibrutinib and continued both drugs up to Cycle 24 Day 28/uMRD4/progression/toxicity. After Cycle 24 Day 28, MRD+ patients continued ibrutinib. Thirty-eight patients (29% with TP53 aberrations; 79% with unmutated IGHV) started venetoclax. Overall response rate with venetoclax was 36 (95%) of 38 patients (20 complete; 16 partial response). Seventeen patients (45%) with uMRD4 at Cycle 12 Day 1 discontinued venetoclax. Nineteen (55%) MRD+ subjects added ibrutinib. After a median of 7 months (range, 3-10 months) of combined treatment, 16 (84%) of 19 achieved uMRD4, thus stopping both drugs. Two MRD+ patients at Cycle 24 Day 28 continued ibrutinib until progression/toxicity. After a median follow-up of 36.5 months, median progression-free survival was not reached; 10 patients progressed (4 restarted venetoclax, 3 without treatment need, 2 developed Richter transformation, and 1 dropped out). Seven (22%) of 32 patients remain uMRD4 after 3 years of follow-up. Neutropenia was the most frequent grade 3 to 4 adverse event; no grade 5 events occurred on study. This sequential MRD-guided approach led to uMRD4 in 33 (87%) of 38 patients, with venetoclax monotherapy or combined with ibrutinib, delivering treatment combination only in a fraction, and ultimately identifying the few patients benefiting from continuous therapy. This trial was registered at www.clinicaltrials.gov as # NCT04754035.

COVID-19 infection in chronic myeloid leukaemia after one year of the pandemic in Italy. A Campus CML report.

Limited information is available on the impact of the COVID-19 pandemic on the management of chronic myeloid leukaemia (CML). The Campus CML network collected retrospective information on 8 665 CML patients followed at 46 centres throughout Italy during the pandemic between February 2020 and January 2021. Within this cohort, we recorded 217 SARS-CoV-2-positive patients (2·5%). Most patients (57%) were diagnosed as having SARS-CoV-2 infection during the second peak of the pandemic (September 2020 to January 2021). The majority (35%) was aged between 50 and 65 years with a male prevalence (73%). Fifty-six percent of patients presented concomitant comorbidities. The median time from CML diagnosis to SARS-CoV-2 infection was six years (three months to 18 years). Twenty-one patients (9·6%) required hospitalization without the need of respiratory assistance, 18 (8·2%) were hospitalized for respiratory assistance, 8 (3·6%) were admitted to an intensive care unit, while 170 (78%) were only quarantined. Twenty-three percent of patients discontinued tyrosine kinase inhibitor (TKI) therapy during the infection. Twelve patients died due to COVID-19 with a mortality rate of 5·5% in the positive cohort and of 0·13% in the whole cohort. We could also document sequelae caused by the SARS-CoV-2 infection and an impact of the pandemic on the overall management of CML patients.

Molecular response and quality of life in chronic myeloid leukemia patients treated with intermittent TKIs: First interim analysis of OPTkIMA study.

BACKGROUND: Intermittent treatment with TKIs is an option for the great majority (70%-80%) of CML patients who do not achieve a stable deep molecular response and are not eligible for treatment discontinuation. For these patients, the only alternative is to assume TKI continuously, lifelong. METHODS: The Italian phase III multicentric randomized OPTkIMA study started in 2015, with the aim to evaluate if a progressive de-escalation of TKIs (imatinib, nilotinib, and dasatinib) is able to maintain the molecular response (MR3.0 ) and to improve Health Related Quality of Life (HRQoL). RESULTS: Up to December 2018, 166/185 (90%) elderly CML patients in stable MR3.0 /MR4.0 completed the first year of any TKI intermittent schedule 1 month ON and 1 month OFF. The first year probability of maintaining the MR3.0 was 81% and 23.5% of the patients who lost the molecular response regained the MR3.0 after resuming TKI continuously. Patients' HRQoL at baseline was better than that of matched peers from healthy population. Women was the only factor independently associated with worse baseline HRQoL (p > 0.0001). Overall, global HRQoL worsened at 6 (p < 0.001) but returned to the baseline value at 12 months and it was statistically significantly worse in women (p = 0.001). CONCLUSIONS: De-escalation of any TKI by 1 month ON/OFF schedule maintains the MR3.0 /MR4.0 in 81% of the patients during the first 12-24 months. No patients progressed to accelerated/blastic phase, all the patients (23.5%) losing MR3.0 regained the MR3.0 and none suffered from TKI withdrawn syndrome. The study firstly report on HRQoL in elderly CML patients moving from a continuous daily therapy to a de-escalated intermittent treatment.

Prospective assessment of NGS-detectable mutations in CML patients with nonoptimal response: the NEXT-in-CML study.

In chronic myeloid leukemia (CML) patients, tyrosine kinase inhibitors (TKIs) may select for drug-resistant BCR-ABL1 kinase domain (KD) mutants. Although Sanger sequencing (SS) is considered the gold standard for BCR-ABL1 KD mutation screening, next-generation sequencing (NGS) has recently been assessed in retrospective studies. We conducted a prospective, multicenter study (NEXT-in-CML) to assess the frequency and clinical relevance of low-level mutations and the feasibility, cost, and turnaround times of NGS-based BCR-ABL1 mutation screening in a routine setting. A series of 236 consecutive CML patients with failure (n = 124) or warning (n = 112) response to TKI therapy were analyzed in parallel by SS and NGS in 1 of 4 reference laboratories. Fifty-one patients (22 failure, 29 warning) who were negative for mutations by SS had low-level mutations detectable by NGS. Moreover, 29 (27 failure, 2 warning) of 60 patients who were positive for mutations by SS showed additional low-level mutations. Thus, mutations undetectable by SS were identified in 80 out of 236 patients (34%), of whom 42 (18% of the total) had low-level mutations somehow relevant for clinical decision making. Prospective monitoring of mutation kinetics demonstrated that TKI-resistant low-level mutations are invariably selected if the patients are not switched to another TKI or if they are switched to a inappropriate TKI or TKI dose. The NEXT-in-CML study provides for the first time robust demonstration of the clinical relevance of low-level mutations, supporting the incorporation of NGS-based BCR-ABL1 KD mutation screening results in the clinical decision algorithms.

Managing chronic myeloid leukemia for treatment-free remission: a proposal from the GIMEMA CML WP.

Several papers authored by international experts have proposed recommendations on the management of BCR-ABL1+ chronic myeloid leukemia (CML). Following these recommendations, survival of CML patients has become very close to normal. The next, ambitious, step is to bring as many patients as possible into a condition of treatment-free remission (TFR). The Gruppo Italiano Malattie EMatologiche dell'Adulto (GIMEMA; Italian Group for Hematologic Diseases of the Adult) CML Working Party (WP) has developed a project aimed at selecting the treatment policies that may increase the probability of TFR, taking into account 4 variables: the need for TFR, the tyrosine kinase inhibitors (TKIs), the characteristics of leukemia, and the patient. A Delphi-like method was used to reach a consensus among the representatives of 50 centers of the CML WP. A consensus was reached on the assessment of disease risk (EUTOS Long Term Survival [ELTS] score), on the definition of the most appropriate age boundaries for the choice of first-line treatment, on the choice of the TKI for first-line treatment, and on the definition of the responses that do not require a change of the TKI (BCR-ABL1 ≤10% at 3 months, ≤1% at 6 months, ≤0.1% at 12 months, ≤0.01% at 24 months), and of the responses that require a change of the TKI, when the goal is TFR (BCR-ABL1 >10% at 3 and 6 months, >1% at 12 months, and >0.1% at 24 months). These suggestions may help optimize the treatment strategy for TFR.

Excellent outcomes of 2G-TKI therapy after imatinib failure in chronic phase CML patients.

Second-generation tyrosine kinase inhibitors (2G-TKIs) dasatinib and nilotinib produced historical rates of about 50% complete cytogenetic response (CCyR) and about 40% major molecular response (MMR) in chronic myeloid leukaemia (CML) patients failing imatinib. Direct comparisons between dasatinib and nilotinib are lacking, and few studies addressed the dynamics of deep molecular response (DMR) in a "real-life" setting. We retrospectively analyzed 163 patients receiving dasatinib (n = 95) or nilotinib (n = 68) as second-line therapy after imatinib. The two cohorts were comparable for disease's characteristics, although there was a higher rate of dasatinib use in imatinib-resistant and of nilotinib in intolerant patients. Overall, 75% patients not in CCyR and 60% patients not in MMR at 2G-TKI start attained this response. DMR was achieved by 61 patients (37.4%), with estimated rate of stable DMR at 5 years of 24%. After a median follow-up of 48 months, 60% of patients persisted on their second-line treatment. Rates and kinetics of cytogenetic and molecular responses, progression-free and overall survival were similar for dasatinib and nilotinib. In a "real-life" setting, dasatinib and nilotinib resulted equally effective and safe after imatinib failure, determining high rates of CCyR and MMR, and a significant chance of stable DMR, a prerequisite for treatment discontinuation.

Minimal Residual Disease Assessment and Risk-based Therapy in Acute Lymphoblastic Leukemia.

The study of minimal residual disease (MRD) in adult patients with acute lymphoblastic leukemia (ALL) allows a greater refinement of the individual risk classification and is the best support for risk-specific therapy with or without allogeneic hematopoietic cell transplantation (HCT). Using case-specific sensitive molecular probes or multiparametric flow cytometry on marrow samples obtained from the end of induction until midconsolidation, MRD assays can detect up to 1 leukemic cell of 10,000 total mononuclear cells (sensitivity, 0.01%; ie, ≥104). This cutoff, presently bound to technical limitations and subject to improvement, reflects the individual chemosensitivity and is strongly correlated with treatment outcome. The chance for cure is approximately 70% in the MRD-negative subset but only 20% to 30% in MRD-positive patients, in any diagnostic and risk subset. As shown by prospective trials from Germany, Italy, Spain, and France-Switzerland-Belgium, approximately 50% to 70% of unselected adult patients with Philadelphia-negative ALL achieve and maintain an early MRD response, whereas the remainder do not, including a substantial proportion of clinically standard-risk patients, and require an HCT to avert at least partially the risk of relapse. Along with the diffusion of more effective "pediatric-inspired" chemotherapy programs, the MRD analysis is an integral part of a modern management strategy, guiding the decision process to transplant or not, in which case nonrelapse mortality using HCT in first remission-still 10% to 20%-is totally abolished. The use of new agents such as monoclonal antibodies, small inhibitors, and chimeric antigen receptor T cells is opening a new era of MRD-directed therapies, that will further increase survival rates.

Burkitt lymphoma in adolescents and young adults: management challenges.

About one-half of all Burkitt lymphoma (BL) patients are younger than 40 years, and one-third belong to the adolescent and young adult (AYA) subset, defined by an age between 15 and 25-40 years, based on selection criteria used in different reports. BL is an aggressive B-cell neoplasm displaying highly characteristic clinico-diagnostic features, the biologic hallmark of which is a translocation involving immunoglobulin and c-MYC genes. It presents as sporadic, endemic, or epidemic disease. Endemicity is pathogenetically linked to an imbalance of the immune system which occurs in African children infected by malaria parasites and Epstein-Barr virus, while the epidemic form strictly follows the pattern of infection by HIV. BL shows propensity to extranodal involvement of abdominal organs, bone marrow, and central nervous system, and can cause severe metabolic and renal impairment. Nevertheless, BL is highly responsive to specifically designed short-intensive, rotational multiagent chemotherapy programs, empowered by the anti-CD20 monoclonal antibody rituximab. When carefully applied with appropriate supportive measures, these modern programs achieve a cure rate of approximately 90% in the average AYA patient, irrespective of clinical stage, which is the best result achievable in any aggressive lymphoid malignancy to date. The challenges ahead concern the following: optimization of management in underdeveloped countries, with reduction of diagnostic and referral-for-care intervals, and the applicability of currently curative regimens; the development of lower intensity but equally effective treatments for frail or immunocompromised patients at risk of death by complications; the identification of very high-risk patients through positron-emission tomography and minimal residual disease assays; and the assessment in these and the few refractory/relapsed ones of new monoclonals (ofatumumab, blinatumomab, inotuzumab ozogamicin) and new molecules targeting c-MYC and key proliferative steps of B-cell malignancies.

Role of blood cells dynamism on hemostatic complications in low-risk patients with essential thrombocythemia.

Patients with essential thrombocythemia (ET) aged less than 60 years, who have not suffered a previous vascular event (low-risk patients), may develop thrombotic or hemorrhagic events. So far, it has not been possible to identify useful markers capable of predicting which of these patients are more likely to develop an event and therefore who needs to be treated. In the present study, we analysed the relationship between vascular complications and longitudinal blood counts of 136 low-risk ET patients taken over a sustained period of time (blood cells dynamism). After a median follow-up of 60 months, 45 out of 136 patients (33%) suffered 40 major thrombotic and 5 severe hemorrhagic complications. A total number of 5,781 blood counts were collected longitudinally. Thrombotic and hemorrhagic events were studied together (primary endpoint) but also separately (thrombotic alone = secondary endpoint; hemorrhagic alone = tertiary endpoint). The primary endpoint showed no significant association between platelet and WBC count at diagnosis and risk of any event (platelet, p = 0.797; WBC, p = 0.178), while Hb at baseline did show an association (p = 0.024). In the dynamic analysis with Cox regression model, where the blood count values were studied by time of follow-up, we observed that the risk for Hb was 1.49 (95% CI 1.13-1.97) for every increase of 1 g/dL, and that this risk then marginally decreased during follow-up. WBC was associated with an increased risk at baseline for every increase of 1 × 10(9)/L (hazard ratio (HR) 1.07, 95% CI 1.01-1.13, p = 0.034), the risk was stable during follow-up (HR 0.95, p = 0.187 at 60 months). Also, for each increment at baseline of 100 × 10(9) platelets/L, HR was increased by 1.08 (95% CI 0.97-1.22, p = 0.159) and decreases during follow-up. In conclusion, this study is the first to evaluate in ET low-risk patients, the risk of developing a thrombotic/hemorrhagic event considering blood counts over time. Overall our study shows that the risk changes over time. For example, the risk associated with WCC is not linear as previously reported. An interesting new finding is that PLT and even Hb contribute to the risk of developing vascular events. Future treatments should take into consideration these findings and aim to control all parameters over time. We believe this early study may help develop a dynamic analysis model to predict thrombosis in the single patient. Further studies are now warranted to further validate our findings.

Modern immunotherapy of adult B-lineage acute lymphoblastic leukemia with monoclonal antibodies and chimeric antigen receptor modified T cells.

The introduction of newer cytotoxic monoclonal antibodies and chimeric antigen receptor modified T cells is opening a new age in the management of B-lineage adult acute lymphoblastic leukemia. This therapeutic change must be very positively acknowledged because of the limits of intensive chemotherapy programs and allogeneic stem cell transplantation. In fact, with these traditional therapeutic tools the cure can be achieved in only 40-50% of the patients. The failure rates are particularly high in the elderly, in patients with post-induction persistence of minimal residual disease and especially in refractory/relapsed disease. The place of the novel immunotherapeutics in improving the outcome of adult patients with B-lineage acute lymphoblastic leukemia is reviewed.

Current and future management of Ph/BCR-ABL positive ALL.

Following the introduction of targeted therapy with tyrosine kinase inhibitors (TKI) at the beginning of the past decade, the outcome of patients with Philadelphia-chromosome positive acute lymphoblastic leukemia (Ph+ ALL) has dramatically improved. Presently, the use of refined programs with first/second generation TKI's and chemotherapy together with allogeneic stem cell transplantation allow up to 50% of all patients to be cured. Further progress is expected with the new TKI ponatinib, overcoming resistance caused by T315I point mutation, other targeted therapies, autologous transplantation in molecularly negative patients, therapeutic monoclonal antibodies like inotuzumab ozogamicin and blinatumomab, and chimeric antigen receptor-modified T cells. Ph+ ALL could become curable in the near future even without allogeneic stem cell transplantation, minimizing the risk of therapy-related death and improving greatly the quality of patients' life.

EUTOS score predicts long-term outcome but not optimal response to imatinib in patients with chronic myeloid leukaemia.

To test the recently developed EUTOS score in predicting optimal response to imatinib and the long-term outcome, 265 patients with early chronic phase chronic myeloid leukaemia treated with standard dose imatinib were analysed. Achievement of optimal response endpoints were higher in low-risk patients, though the difference was not statistically significant: PCyR at 6th month 86% vs 67% (p=0.06), CCyR at 12th month 80% vs 63% (p=0.09), MMR at 18th month 61% vs 36% (p=0.11). However, EUTOS score was predictive for the long-term response. With a median follow-up of 61 months, 53% high-risk patients experienced imatinib failure, compared to 23% in the low-risk group (p=0.013). Among high-risk patients, 4/17 (23%) progressed to accelerated/blastic phase or died, compared to 11/248 (5%) low-risk patients, with 5-year progression-free survival rates of 84±10% and 96±1%, respectively (p=0.04). Our data confirm that EUTOS score envisions the long-term outcome of imatinib therapy.

Bendamustine in chronic lymphocytic leukemia: outcome according to different clinical and biological prognostic factors in the everyday clinical practice.

Bendamustine proved to be effective for the treatment of chronic lymphocytic leukemia (CLL). However, the relationship between its activity with clinico-biological prognosticators has been addressed only in few studies. We retrospectively evaluated the efficacy of bendamustine, in a real-life contest, on 142 patients, median age 70 years, median number of previous regimens 2 (0-8, 13% previously untreated). Bendamustine was administered for a median number of 4 cycles, in 84% of cases with rituximab. Overall (ORR) and complete response (CRR) rates were 68 and 16.5%, respectively. Multivariate analysis demonstrated a relationship between ORR and number of prior treatments (OR 0.25, 95% CI 0.08-0.71; P = 0.009), del(17p) (OR 0.10, 95% CI 0.03-0.32; P < 0.001) and concomitant rituximab (OR 4.37, 95% CI 1.12-17.04; P = 0.033). The estimated 1- and 2-years overall survival (OS) and progression free survival (PFS) rates were 76, 61, 51, and 26%, respectively. Previous sensitivity to fludarabine (HR 0.36, 95% CI 0.16-0.82), response to bendamustine (HR 0.21, 95% CI 0.10-0.45), and del(17p) (HR 2.18, 95% CI 1.002-4.74) had a prognostic significance in multivariate analysis for PFS, while the number of previous therapies (HR 3.48, 95% CI 1.29-9.38; P = 0.014), concomitant use of rituximab (HR 0.32, 95% CI 0.11-0.93) and response to bendamustine (HR 0.22, 95% CI 0.07-0.66) were significant for OS. Side effects included grade 3-4 neutropenia, infections, thrombocytopenia and anemia which occurred in 40, 14, 14, and 10% of patients, respectively. These results confirm the activity and safety of bendamustine and rituximab combination even in patients with unfavorable clinical and biological features excluding del(17p).

Positron emission tomography in the staging of patients with Hodgkin's lymphoma. A prospective multicentric study by the Intergruppo Italiano Linfomi.

In this prospective multicentric study, we investigated the contribution of positron emission tomography (PET) scanning to the staging of Hodgkin's lymphoma (HL) by computed tomography (CT) and attempted to determine whether it has any impact on therapeutic approach. One hundred eighty six consecutive patients with HL from six Italian centers were enrolled in this study. They were staged with conventional methods; 2-[fluorine-18]fluoro-2-deoxy-D: -glucose PET scanning were prospectively compared to CT. CT and FDG-PET stages were concordant in 156 patients (84%) and discordant in 30 patients (16%). PET stage in comparison to CT stage was higher in 27 patients (14%) and lower in 3 patients (1%). The programmed treatment strategy was modified in 11 out of 30 patients (37%) after the definition of final stage. If we considered the 123 CT staged patients with localized stage, ten patients (8%) with a change of stage from localized to advanced after PET evaluation were treated with different strategy. FDG-PET was shown to be a relevant, non-invasive method that supplements conventional procedures and should therefore be used routinely to stage HL, particularly in early stage patients, where a change in stage may modify disease management.

The predictive value of positron emission tomography scanning performed after two courses of standard therapy on treatment outcome in advanced stage Hodgkin's disease.

BACKGROUND AND OBJECTIVES: We explored the predictive value on therapy outcome of an early evaluation of treatment response by 18F-fluorodeoxyglucose position emission tomography (18F-FDG-PET) scan performed after two courses of conventional standard-dose chemotherapy in advanced-stage Hodgkin's disease. DESIGN AND METHODS: One hundred and eight patients with newly-diagnosed Hodgkin's disease in stage IIA with adverse prognostic factors, or in stage IIB through IVB, were re-staged with FDG-PET after two cycles of ABVD (PET-2). The end-point of the study was the predictive value of PET-2 on 2-year progression-free survival and 2-year failure-free survival. No treatment variation based only on PET-2 results was allowed. RESULTS: Eighty-eight patients attained complete remission (CR) while 20 showed disease progression during therapy or within 6 months after having reached CR; one patient relapsed. PET-2 was positive in 20 patients: 17 progressed during therapy, one relapsed and two remained in CR. By contrast, 85/88 (97%) patients with a negative PET-2 remained in CR; three progressed or relapsed early after the end of the chemotherapy. Thus, the positive predictive value of a PET-2 was 90% and the negative predictive value was 97%. The sensitivity, specificity and overall accuracy of PET-2 were 86%, 98% and 95%, respectively. The 2-year probability of failure-free survival for PET-2 negative and for PET-2 positive patients was 96% and 6%, respectively (log rank test = 116.7, p < 0.01). INTERPRETATION AND CONCLUSIONS: 18F-FDG-PET scan performed after two courses of conventional standard-dose chemotherapy in advanced-stage Hodgkin's disease was able to predict treatment outcome in 103/108 (95%) of the patients.