Cassileth, Peter A.

Abstract Over the past decade several prospective studies of post-remission therapy in AML have compared allogeneic hematopoietic stem cell transplantation (HSCT), autologous HSCT and chemotherapy. The data are appropriately presented by intention-to-treat analyses. However, such analyses do not provide information to the clinician or patient as to outcome from the initiation of post-remission therapy, be it HSCT or chemotherapy. Furthermore, such analyses are impossible to interpret when a significant percentage of patients do not receive their intended therapies (for example, only 54% of patients randomized to autologous HSCT; Cassileth, NEJM, 1998). Finally, such studies present survival data that may not be relevant to current practice where the mortality from autologous HSCT has decreased sharply (for example, 14% non-relapse mortality from autologous HSCT; Cassileth, NEJM, 1998). In the current analysis, results from 4 consecutive ECOG studies that included autologous HSCT were analyzed and the data collated. In PC486 patients received standard induction followed by allogeneic HSCT if they had a compatible sibling; otherwise they were to undergo an autologous HSCT without any prior consolidation (Cassileth, JCO, 1993). E4995 studied standard induction with added high-dose cytarabine (HiDAC) intensification on D 8–10, followed by 2 courses of HiDAC consolidation. All patients were to undergo an autologous HSCT after induction and consolidation (Cassileth, Leuk Lymph, 2005). E3489 was a US Intergroup study in which patients received standard induction (3 + 7). If in CR, all patients received an attenuated course of induction (2 + 5). Patients who had a histocompatible sibling were assigned to allogeneic HSCT; those without a donor were randomized to an autologous HSCT or chemotherapy (Cassileth, NEJM, 1998). E1900 is an ongoing phase III study in which patients receive standard induction followed by allogeneic HSCT or two courses of HiDAC followed by autologous HSCT. The latter study is ongoing; therefore, only data describing transplant-related mortality (TRM) are presented. The relapse rate from start of each post-remission regimen in these studies, based on therapy actually received and not on intention-to-treat analysis, is presented in table 1 and the TRM is presented in table 2. Table 1. Relapse Rate from Start of Post-Remission Therapy Cytogenetics Allogeneic HSCT (n=85) Autologous HSCT (n=113) Chemotherapy (n=109) Favorable 11.8% (2/17) 10.5% (2/19) 60% (12/20) Intermediate 20.5% (8/39) 32.3% (10/31) 53.7% (22/41) Unfavorable 16.7% (2/12) 41.7% (5/12) 83.3% (15/18) Unknown 23.5% (4/17) 33.3% (17/51) 56.7% (17/30) Table 2. Treatment-Related Mortality after Post-Remission Therapy Allogeneic HSCT Autologous HSCT – Marrow Autologous HSCT – Blood Chemotherapy Study E3489, E4995, E1900 E3489, PC 486 E4995, E1900 E3489 Treatment-related mortality 15.3% (18/117) 11% (16/85) 1.5% (2/135) 2.7% (3/109) In conclusion: The TRM after autologous HSCT using mobilized peripheral blood has decreased substantially in recent years. As shown in table 2, in PC486 and E3489 where bone marrow was harvested and treated with perfosfamide (4-HC) prior to cryo-preservation, the TRM was significantly greater than in the later studies, E4995 and E1900, where peripheral blood was harvested after priming with chemotherapy and/or cytokines. The lower relapse rate post autologous transplant, together with the lower procedural mortality with current practice, may confer a survival advantage in future prospective studies of autologous HSCT versus chemotherapy. While absolute comparisons cannot be made, as the timing of each therapy may not be identical, these data provide crucial information for informed and patient/physician discussions prior to initiation of postremission therapy.

Abstract Results from clinical trials may change with time. Data presented in initial abstracts or early reports are often different from what appears in subsequent publications, sometimes due to a more rigorous analysis (as in initial response rates) or to maturity of data (as in reports of survival). Survival curves usually provide projected data based on Kaplan-Meier analyses. Such data may change with time when unexpected events occur (as, for example, relapse after T-cell depleted allogeneic transplants) or more patients advance to the initially projected time point. For AML, several groups have reported that there are very few relapses beyond 3 years. At issue is the optimal time for reporting these survival data. Table 1 reports data from 6 consecutive clinical trials addressing induction and post-remission questions in AML patients performed by ECOG. These data compare the 3-year overall survival (OS) and disease-free survival (DFS) for the identical cohorts of patients as presented at 1 year and at 3 years after completion of the study accrual. PC 486 was a phase II study of induction therapy followed by allogeneic or autologous transplant without prior consolidation. E 3489 was a US intergroup study in which patients received post-induction therapy using an allogeneic transplant (allo), an autologous transplant (auto) or chemotherapy (chemo). E1490 was a study in older adults of induction and consolidation with GM-CSF or placebo. E2491 was an intergroup study comparing ATRA induction versus standard chemotherapy in patients with APL. After consolidation, patients were randomized to maintenance with ATRA versus observation (obs). E3993 was a study in older adults comparing priming with GMCSF or placebo. E4995 was a phase II study of intensified induction and consolidation followed by an autologous transplant. For the same cohorts of patients the 3-year OS tends to decrease as the time from completion of study accrual increases. When looking at the DFS, while a decrease may also occur, in several studies there was an improved DFS with time (for example, in E2491, chemo to ATRA, or in E3993 with GM-CSF priming). There were no changes in either OS or DFS beyond 3 years (data not shown). Table 1: Three-year OS and DFS Presented at Different Time Points OS (%) DFS (%) Study One year Three years One year Three years PC 486 auto or allo HSCT 42 → 38 45 → 39 E 3489 allo HSCT 50 → 50 48 → 47 auto HSCT 47 → 46 39 → 39 chemo 56 → 51 36 → 36 E 1490 Induction / consolidation GM-CSF 23 → 22 23 → 24 placebo 15 → 12 16 → 15 E2491 APL induction+ maintenance ATRA + ATRA 87 → 84 72 → 73 ATRA + obs 83 → 80 61 → 60 chemo + ATRA 81 → 75 43 → 58 chemo + obs 54 → 45 16 → 18 E 3993 Induction/consolidation GM-CSF priming 13 → 11 5 → 10 placebo 14 → 14 9 → 9 E 4995 Induction / consolidation / auto HSCT 54 → 48 63 → 53 In conclusion: For large cooperative group studies, treatment results in AML presented one year from conclusion of study accrual are unlikely to dramatically alter the overall results. Nonetheless, some differences may occur, both in OS and DFS, warranting caution in interpreting the data and comparing with other published reports. Such differences are likely to be even greater if data are presented upon completion of study accrual, prior to one year - although, in a cooperative group setting, this should be balanced against the need to release data for future planning. Publication of interim data, before conclusion of the study accrual, may be misleading and are to be strongly discouraged. Three years appear to be the appropriate time for the publication of definitive survival data.

8011 Background: Maintenance therapy is generally not used in treatment of DLBCL. However, older pts are a unique group in which to study this approach, due to poorer outcome. Methods: As part of intergroup trial E4494/C9793, 415 pts >= 60 years (yr) of age with DLBCL who responded to induction therapy with CHOP or R-CHOP were randomized to MR (rituximab, 375 mg/m2 weekly {wk} X 4 every 6 months for 2 yr) starting 4 wk after the last chemotherapy (n=207) or observation (OBS, n=208) in a prospective 2 × 2 randomized trial design (J Clin Oncol 2006;24:3121). Impact of MR on failure-free survival (FFS) was the primary objective, and impact on time to failure (TTF) and overall survival (OS) were secondary objectives. All p-values are two-sided. Results: Results are presented for 352 centrally reviewed evaluable pts, with a median follow-up after maintenance randomization of 5.5 yr. All results were similar for the intent-to-treat population. Baseline characteristics and response to induction therapy are balanced among the CHOP/R-CHOP pts. At 6 yr, FFS was 46% for those pt who received MR and 36% for the OBS cohort (p=0.005, hazard rate {HR} 0.64); 6-yr OS was 62% for MR and 64% for OBS (p=0.83, HR 0.96). Outcome was also examined in the four treatment subgroups. The 6-yr FFS were: CHOP+MR 44%, CHOP+OBS 35%, R-CHOP+MR 47%, and R- CHOP+OBS 40%. No differences in 6-yr OS were observed according to maintenance randomization following CHOP (57% MR vs 55% OBS) or R-CHOP (67% MR and 72% OBS). Median TTF after maintenance randomization following CHOP+MR was 5.2 yr vs 1.6 yr for CHOP-OBS (p=0.0004), and following R-CHOP+MR was 5.6 yr vs 5.4 yr with R-CHOP-OBS (p=0.50). Proportionately more of the treatment failures occurred within 2 yr after CHOP+OBS (85%) compared to CHOP+MR (61%), p=0.01. In contrast, the proportion of failures within 2 yr was similar for R- CHOP+OBS (47%) and R-CHOP+MR (53%), p=NS. Conclusions: MR after CHOP, but not after R-CHOP, significantly prolongs TTF, but fails to prolong OS, possibly due to a delayed pattern of relapse and/or the efficacy of rituximab in the salvage setting. As 6-yr FFS declined to <50% among R-CHOP responders, with or without MR, there is a need for more effective treatment strategies in older DLBCL pts. No significant financial relationships to disclose.

Abstract This study was coordinated by the ECOG-ACRIN Cancer Research Group (Robert L. Comis, MD and Mitchell D. Schnall, MD, PhD, Group Co-Chairs) and supported in part by Public Health Service Grants CA180794, CA180820, CA180795, CA180791, CA189859, CA180790, CA180853, and from the National Cancer Institute, National Institutes of Health and the Department of Health and Human Services. Its content is solely the responsibility of the authors and does not necessarily represent the official views of the National Cancer Institute. Background: Relapse after achieving a complete remission (CR) in AML portends for a poor prognosis and allogeneic transplant after achieving a second remission is the only chance for cure. Patients who undergo a transplant have a 30-40% chance of long term survival. This is a follow-up of a report published 10 years ago (Rowe JM, ASH 2005, abstract 546) and includes contemporary studies and longer follow-up. The study examines the long term overall survival (OS) of AML patients who relapsed after achieving first CR in 9 successive ECOG-ACRIN trials for newly-diagnosed AML patients (E3483, E3489, PC486, E3993, E4995, E1490, E3997, E1900 and E3999) from March 1984 to November 2008. Methods: OS was defined as time from first relapse to death from any cause. Kaplan-Meier estimates were used to estimate the event-time distributions for OS. Multivariate model stratified on protocol and treatment were used to examine whether the following factors are prognostic for OS from relapse: age, gender, cytogenetic risk, ECOG performance status, WBC, platelets, hemoglobin, marrow blasts, peripheral blasts, and duration of CR. All P values were based on 2-sided tests. Results: A total of 3160 patients were enrolled in the 9 studies. The median follow-up on patients still alive was 10.0 years. Among those 3160 patients enrolled, 1864 (58.9%) achieved first CR of which 1086 (58.2%) had documented relapse. The median age at diagnosis of the relapsed patients was 50 (range: 16-84) and 50.6% were males. Fifty percent of the patients had reliable cytogenetic results. Of those, 13.5% had favorable cytogenetics, 55.8% - intermediate and 30.6% had unfavorable baseline results. The median OS from relapse was 0.5 years. The 2- and 5-year OS were 16(±1)% and 10(±1)%, respectively. This is true in even the most contemporary studies (E1900 and E3999) with median OS of 0.6 and 0.4 years, respectively. By age stratification (< or ≥ 55), 5-year OS was 13(±1)% and 5(±1)%, respectively (figure 1). Among patients<55, those with unfavorable cytogenetics had the poorest prognosis (median OS of 0.4 years and 5-year OS of 6(±3)%. Those with favorable and intermediate cytogenetics had similar OS with 0.7 and 0.6 years median OS and 5-year OS of 16(±5)% and 17(±3)%, respectively (figure 2). Multivariate analysis was perfomed on 517 patients who had enough baseline information, including cytogenetics. Factors that were significantly associated with OS from relapse included: age (p<0.001), ECOG performance status (p=0.04), hemoglobin (p=0.03), cytogenetics (p=0.045) at baseline and duration of CR (p<0.001). Conclusions: The short- and long-term OS of AML patients post-relapse is dismal (<10%). Although age<55 and favorable cytogenetics at diagnosis are relatively good prognostic factors, the general survival of even these patients is very poor. Disappointingly, these data are also applicable to the most contemporary studies. Long-term survival was possible only in the minority of patients who survived the relapse, achieved a second CR and then successfully underwent an allogeneic transplant. These data are crucial when considering post-remission strategy, and suggest that offering a therapy most likely to lead to cure in CR1 is the preferred option. Figure 1. Probability of OS from relapse by age group Figure 1. Probability of OS from relapse by age group Figure 2. Probability of OS from relapse by cytogenetic risk for patients age <55 Figure 2. Probability of OS from relapse by cytogenetic risk for patients age <55 Disclosures Douer: Gilead: Consultancy. Rowe:BioSight Ltd.: Consultancy, Membership on an entity's Board of Directors or advisory committees; BioLineRx Ltd.: Consultancy; Amgen: Consultancy.

Preclinical and clinical evidence suggest a potential advantage for infusional therapy in lymphoma. Sixty-two analyzable patients with predominantly intermediate-grade non-Hodgkin lymphoma received cyclophosphamide (200 mg/m2 per day), doxorubicin (12.5 mg/m2 per day), and etoposide (60 mg/m2per day) (CDE) by continuous intravenous infusion for 4 days (96 hours) every 3 weeks for a maximum of 8 cycles. By the age-adjusted International Prognostic Index (IPI), 42% were at high risk and 58% were at high-intermediate risk. Complete response (CR) occurred in 30 (48%) patients (95% confidence interval [CI], 35%, 64%), and partial response occurred in 16 (26%) patients, yielding an overall response rate of 74% (95% CI, 62%, 84%). Failure-free survival (FFS) rates at 1 and 2 years were 55% (95% CI, 43%, 67%) and 50% (95% CI, 38%, 62%), respectively. When comparing the outcome for 62 patients receiving infusional CDE with historical data derived from 927 IPI-matched lymphoma patients using a Cox proportional hazards model, there was a nonsignificant trend favoring CDE in FFS (P = .12) and overall survival (P = .09). Severe or life-threatening toxicity included neutropenia (68%), anemia (57%), thrombocytopenia (44%), and infection (24%). Two patients (3%) died of treatment-related infectious complications. The primary end point of improving 1-year FFS from 55% to 70% was not achieved with infusional CDE given as initial therapy in patients with poor-risk intermediate-grade lymphoma. It is unlikely that infusional therapy as used in this study produces a 25% or greater relative improvement in FFS compared with standard therapy.

We showed in a phase I trial that the maximum tolerated dose of the ProMACE-CytaBOM regimen in patients with aggressive lymphoma was 200% (Gordon et al, J Clin Oncol 14:1275, 1996). Based on these observations, we initiated a phase II trial designed to determine response, toxicity, and dose intensity using this regimen. We analyzed 74 patients with advanced-stage (III or IV) or bulky stage II aggressive lymphoma. The overall complete response rate was 69% (72% in evaluable patients). With a median follow-up of 4.5 years, the median survival has not yet been reached. The 4-year survival rate is 73% (95% confidence interval [CI] 62, 83%) and no difference was observed among International Prognostic Index (IPI) groups. The 4-year disease-free survival was 71% (95% CI 58, 84%) with no statistical difference between patients with IPI 0 to 1 versus 2 to 4. The toxicity was acceptable, though the grade 4 hematologic toxicity rate for this regimen was 100%. Grade 4 nonhematologic toxicity was 36%. Three cases of either myelodysplastic syndrome or acute leukemia occurred at 7 months, 3.4 years, and 4.2 years after registration. Cytogenic analysis was available in two cases, showing inv(16) without French American British classification (FAB) M4 EO histology in one patient and a 5q-syndrome in the other. These data suggest that 200% ProMACE-CytaBOM with either granulocyte-macrophage colony-stimulating factor (GM-CSF) or G-CSF results in a high complete remission rate and a disease-free survival comparable to any prior risk-based analysis in aggressive lymphoma. Before using this regimen in general practice, phase III clinical trials should be conducted.

Abstract Abstract 132 Late relapse in acute myeloid leukemia (AML) has been infrequently studied and variably defined in the literature. Two series have shown that late relapse of AML ≥5 years after first complete remission (CR1) is uncommon, with rates of 1.19–3% (Medeiros et al, Leuk Lymphoma 2007; Verma et al, Leuk Lymphoma 2010). We searched the long-term data available on 784 adults (<60 years-old) who were treated on 1 of 4 ECOG clinical trials (E3483, PC486, E3489, or E1900) and achieved CR1 for reports of late relapse (defined as recurrence of AML ≥3 years after CR1). Median follow-up for the 553 patients last known alive was 11.1 years. The longest median follow-up was 17.2 years on trial PC486. Outcomes We found that 11 patients (1.4%) relapsed late; of these, 2 were treated on E3483, 1 on PC486, 5 on E3489, and 3 on E1900. Seven patients with late relapse died from their disease and 4 were living at last known follow-up. Only 1 patient (0.13%) had recurrence of AML ≥5 years after achieving CR1. It is possible that more late relapses will occur on E1900 (a more recent study with ongoing follow-up). All of these trials except E3483 treated some patients with autologous hematopoietic cell transplantation (autoHCT) as part of post remission therapy. On PC486, no post remission consolidation chemotherapy was administered before autoHCT. Ninety-eight total patients on E3489 and PC486 received autoHCT, and there were no late relapses; on E1900, 2 of the 141 patients treated with autoHCT developed late relapse. No patients who underwent allogeneic (allo) HCT in CR1 experienced late relapse on any of the 4 clinical trials. Nine of the 11 patients with late relapse did not undergo HCT; of these, 5 were consolidated with high-dose cytarabine, 2 received maintenance with low-dose cytarabine and 6-thioguanine, and 2 received unknown post remission therapy. Of the 3 patients with late relapse on E1900, 2 received standard-dose and 1 high-dose daunorubicin with induction. Conclusions Across all 4 trials, only 2 of the 239 patients (0.8%) treated with post remission autoHCT experienced late relapse of AML (≥3 years after CR1), which reinforces previously published data that late relapse after autoHCT is uncommon (Cassileth et al, J Clin Oncol 1993). Furthermore, of the 35 patients treated with autoHCT on PC486, 11 relapsed early and no patients relapsed late, suggesting that post remission chemotherapy may not be necessary before autoHCT. Based on this large AML cohort of nearly 800 patients with long-term follow-up, patients who remain in CCR for at least 3 years have a very low risk of relapse and can be considered cured of their disease. Moreover, given that recurrent AML was extremely rare after 5 years or more of CCR (<0.2%), the risk of therapy-related AML from contemporary induction and post remission strategies including HCT appears to be minimal. Disclosures: No relevant conflicts of interest to declare.

Abstract Background Extramedullary disease (EMD) of acute myeloid leukemia (AML) was described decades ago but the incidence of this phenomenon and its prognostic impact are not clear. It is also uncertain whether every site of EMD has the same significance. This study explored these questions using a large cohort of AML patients treated on consecutive Eastern Cooperative Oncology Group (ECOG) frontline clinical trials. Methods For AML patients enrolled into ECOG clinical trials, the presence of EMD was captured at baseline on case report forms. From patients with newly diagnosed AML, age 15 and above, who were treated on 11 consecutive different clinical trials, we identified those with or without EMD, defined by physical examination, laboratory findings and imaging, without necessarily a biopsy. We used descriptive statistics to summarize patient and disease characteristics. Univariate analyses of potential prognostic factors were done. The Kaplan-Meier method was used to estimate median overall survival (OS) within each prognostic category and differences were explored using the log-rank test. Cox proportional hazards models were used to examine the effect of one-unit increases in continuous variables on OS and for multivariable analyses. Multivariate models were built using backward selection. Factors (or groups of factors) significant at the 0.10 level in univariate analyses were tested for inclusion in the model, and retained if they were significant at the 0.05 level. Results Of the 3,522 patients enrolled in 11 different AML clinical trials, we excluded 281; for diagnosis of other types of leukemia (n=220), no EMD evaluation at baseline (n=41) or no survival data (n=20). The overall incidence of EMD was 23.8% (770 out of the remaining 3,241 patients). The sites involved were: lymph nodes 367 (11.3%) patients, spleen 234 (7.2%), liver 173 (5.3%), skin 146 (4.5%), gingiva 104 (3.2%), central nerve system (CNS) 32 (1%), peripheral nerve system (PNS) 8 (0.2%) and other sites 134 (4.1%). In 65 cases (8.4%) EMD was confirmed by biopsy. Most of the patients (64.4%) had only one site of EMD, 163 (21.2%) had 2 sites, 75 (9.7%) - 3 sites, 28 (3.6%) - 4 sites, and 4 patients (0.5%) each had 5 or 6 sites. EMD patients compared to those without EMD; tend to be younger (median age 45.7 vs 52.9 years); male (57.7% vs 52%); poorer ECOG performance status (76.4% with ECOG 0-1 vs 85.9%) and with higher white blood cell count (WBC) at diagnosis (median of 41.6/µl vs 10.2/µl). In univariate analysis, having EMD was associated with a shorter OS (P=0.006). Examination of individual EMD sites revealed that skin (P=0.002), spleen (P=0.0002) and liver (P=0.0007) but not CNS (P=0.35), PNS (P=0.53), nodal involvement (P=0.85) and gingival hypertrophy (P=0.14), were associated with poorer OS. Using proportional hazards models for continuous factors, each additional site of EMD conferred a 9.4% increase in the risk of death. In a multivariable model, after adjusting for known prognostic factors (such as: age, WBC count and cytogenetic risk group), the presence of EMD, number of EMD sites and any specific EMD site were not independently prognostic. Of 165 patients with known favorable cytogenetics EMD was present in only 22 patients (13%). This group appeared to have a worse prognosis, but the numbers are too small for a definitive assessment (figure 1). Conclusions Extramedullary disease is common in newly diagnosed AML with an incidence of almost 24%, but CNS involvement is very rare (0.95%). In contrast to published data, no site of EMD was found to have an independent prognostic impact in multivariate analysis. This large dataset emphasizes the importance of evaluating large number of patients and considering all known risk factors in the multivariate analysis. Disclosures: No relevant conflicts of interest to declare.