PURPOSE:Because both t(8;21) and inv(16) disrupt core binding factor (CBF) in acute myeloid leukemia (AML) and confer relatively favorable prognoses, these cytogenetic groups are often treated similarly. Recent studies, however, have shown different gene profiling for the two groups, underscoring potential biologic differences. Therefore, we sought to determine whether these two cytogenetic groups should also be considered separate entities from a clinical standpoint.PATIENTS AND METHODS:We analyzed 144 consecutive adults with t(8;21) and 168 with inv(16) treated on Cancer and Leukemia Group B front-line studies. We compared pretreatment features, probability of achieving complete remission (CR), overall survival (OS) and cumulative incidence of relapse (CIR) between the two groups.RESULTS:With a median follow-up of 6.4 years, for CBF AML as a whole, the CR rate was 88%, 5-year OS was 50% and CIR was 53%. After adjusting for covariates, patients with t(8;21) had shorter OS (hazard ratio [HR] = 1.5; P = .045) and survival after first relapse (HR = 1.7; P = .009) than patients with inv(16). Unexpectedly, race was an important predictor for t(8;21) AML, in that nonwhites failed induction more often (odds ratio = 5.7; P = .006) and had shorter OS than whites when certain secondary cytogenetic abnormalities were present. In patients with t(8;21) younger than 60 years, type of induction also correlated with relapse risk. For inv(16) AML, secondary cytogenetic abnormalities (especially +22) and male sex predicted better outcome.CONCLUSION:When the prognostic impact of race, secondary cytogenetic abnormalities, sex, and response to salvage treatment is considered, t(8;21) and inv(16) AMLs seem to be distinct clinical entities and should be stratified and reported separately.

Purpose As most patients with acute myeloid leukemia (AML) with morphologic complete remission (CR) ultimately relapse, better predictors for outcome are needed. Recently, Cheson et al suggested using cytogenetic remission (CRc) as part of the criteria for CR. To our knowledge, ours is the first relatively large study evaluating the usefulness of CRc attained immediately following induction chemotherapy. Patients and Methods We included AML patients treated on Cancer and Leukemia Group B front-line studies with cytogenetic samples obtained at diagnosis and at the first day of documented CR following induction. Patients with abnormal cytogenetics at diagnosis, and normal cytogenetics at CR (NCR; n = 103) were compared with those with abnormal cytogenetics both at diagnosis and at CR (ACR; n = 15) for overall survival (OS), disease-free survival (DFS), and cumulative incidence of relapse (CIR). Cox proportional hazards models determined the prognostic significance of cytogenetics at CR, adjusting for other covariates. Results Clinical features were similar for both groups, with the exception of favorable cytogenetics [t(8;21), inv(16)/t(16;16), t(15;17)] at diagnosis, which was more frequent (P = .03) in the NCR group. Median follow-up was 3.1 years (range, 1.0 to 11.4 years). ACR patients had significantly shorter OS (P = .006) and DFS (P = .0001), and higher CIR (P = .0001). In multivariable models, the NCR and ACR groups were predictors for OS (P = .03), DFS (P = .02), and CIR (P = .05). The relative risk of relapse or death was 2.1 times higher for ACR patients than for NCR patients (95% CI, 1.1 to 3.9). Conclusion Our data suggest that converting to normal karyotype at the time of first CR is an important prognostic indicator and support the use of CRc as a criterion of CR in AML.

Abstract Previous studies have identified broad cytogenetic risk groups in AML, by comparing outcome of pts with different recurring abnormalities, using cytogenetically normal pts as the reference group. Pts with better survival were considered as “favorable”, and those with worse outcome as “unfavorable” risk. To identify prognostic cytogenetic groups for complete remission (CR) and overall survival (OS), without the selection of a reference group, we used classification trees and tree-structured survival analysis (TSSA). We analyzed the outcome of 600 AML pts ≥60 years (yrs), enrolled in the prospective CALGB cytogenetic study 8461 and treated on CALGB front-line AML protocols. Analysis was restricted to cytogenetic aberrations occuring in ≥5 pts. Once prognostic cytogenetic abnormalities for CR and OS were identified, multivariable models were constructed. Median age was 68 (range, 60–86) yrs, and 98% had de novo AML. The most common karyotypes were normal (46%), complex with ≥3 abnormalities (complex ≥3, 19%), and ≥5 abnormalities (complex ≥5, 14%). Core binding factor (CBF) abnormalities, ie, inv(16) and t(8;21), occurred in 5%. Overall, 49.5% of pts achieved CR with only 7% (95%CI: 5%–9%) alive at 5 yrs. Table 1 shows prognostic cytogenetic risk groups identified by classification trees and TSSA for CR and OS, respectively. Table 1: Prognostic Cytogenetic Groups by Tree Analysis CR OS Risk group CR rate Risk group 5-yr OS (95% CI) *P<0.05 compared to CBF; CI, confidence interval Complex≥3 30%* CBF 20 (6–20)% Abnormal, non CBF 46%* <5 abnormalities without CBF or −7 8 (5–10)% Normal 57% Complex≥5 0% CBF 75% −7 0% Table 2 shows the multivariable analyses adjusting for other baseline clinical variables. Only lower % circulating blasts (P=0.0002) and cytogenetic risk groups (P<0.0001) predicted CR. Compared to CBF pts, the odds of CR were significantly lower for pts with complex ≥3 and abnormal, non-CBF karyotypes, whereas the odds of CR for cytogenetically normal pts was not significantly different from CBF pts. For OS, cytogenetic risk groups (P<0.0001), older age (P=0.03), and higher WBC at diagnosis (P=0.02) predicted shorter survival. Compared to CBF pts, the risk of death was significantly higher for those with complex ≥5 karyotype, −7, and <5 abnormalities without CBF or −7. Table 2: Multivariable Analyses CR OS Significant Variables OR (95% CI) Significant Variables HR (95% CI) *CBF is the reference group; OR, odds ratio of achieving CR; HR, hazard ratio of death; CI, confidence interval % circulating blasts 0.90 (0.84–0.95) Age 1.28 (1.09–1.50) Cytogenetics group* WBC 1.03 (1.01–1.04) Complex≥3 0.12 (0.05–0.33) Cytogenetics group* Abnormal, non CBF 0.26 (0.10–0.65) Complex≥5 4.53 (2.80–7.32) Normal 0.44 (0.18–1.09) −7 2.57 (1.39–4.76) <5 abnormalities without CBF or −7 1.62 (1.07–2.46) We conclude that pre-treatment cytogenetics are predictive of CR and OS of older AML pts, particularly identifying pts with complex ≥5 karyotype and −7, who benefit minimally if at all from standard chemotherapy. Such pts may be better suited for investigational therapy or only supportive care.

PURPOSEEvaluate the outcome of induction and postremission therapy in adults younger than 60 years with normal cytogenetics acute myeloid leukemia (AML).PATIENTS AND METHODSIn 490 patients, induction included cytarabine and daunorubicin (AD) or cytarabine and escalated doses of daunorubicin and etoposide +/- PSC-833 (ADE/ADEP). Intensification included one cycle of high-dose cytarabine (HDAC) followed by etoposide/cyclophosphamide and mitoxantrone/diaziquone (group I), three HDAC cycles (group II), four intermediate-dose cytarabine (IDAC) or HDAC cycles (group III), or one HDAC/etoposide cycle and autologous stem-cell transplantation (ASCT; group IV).RESULTSOf 350 patients receiving AD, 73% achieved complete remission (CR), compared with 82% of 140 receiving ADE/ADEP (P = .04). Splenomegaly was associated with a lower CR rate (P < .001), and ADE/ADEP, with a higher CR rate in younger patients (P = .005). The 5-year disease-free survival (DFS) rate was 28% each for intensification groups I and II, compared with 41% and 45% for groups III and IV, respectively (P = .02). The 5-year cumulative incidence of relapse (CIR) was 62% and 67% for groups I and II, respectively, compared with 54% and 44% for groups III and IV, respectively (P = .049). The type of postremission intensification remained significant for DFS and CIR in multivariable analysis.CONCLUSIONIn younger adults with normal cytogenetics AML, splenomegaly predicts a lower CR rate, and the postremission strategies of either four cycles of I/HDAC or one cycle of HDAC/etoposide followed by ASCT are associated with improved DFS and reduced relapse compared with therapies that include fewer cycles of cytarabine or no transplantation.

6514 Background: As most AML patients (pts) with morphologic CR ultimately relapse, better predictors for outcome are needed. Recently, Cheson et al. (JCO 2003;21:4642) proposed cytogenetic remission as part of the criteria for CR (CRc). This is the 1st large study of usefulness of CRc. Methods: Karyotypes at diagnosis (dx) and at date of 1st CR from pts treated on CALGB front-line studies were centrally reviewed. Pts with abnormal cytogenetics at dx and normal cytogenetics at CR (NCR; n=103) were compared to pts with abnormal cytogenetics both at dx and CR (ACR; n=16) for OS, DFS and cumulative incidence of relapse (CIR). Cox proportional hazards models assessed the prognostic impact of cytogenetics at CR, adjusting for other covariates. Results: Clinical features were similar for both groups, except favorable cytogenetics [t(8;21), inv(16), t(15;17)] at dx was present in 60 (58%) NCR vs 4 (25%) ACR pts (P=0.02) and NCRs had higher % marrow blasts (P=0.03). Median follow-up was 3.1 years (range, 1.0–11.4). ACRs had shorter OS (P=0.003) and DFS (P<0.0001) and higher CIR (P<0.0001). At 3 and 5 years, the rate of relapse or death was worse for ACRs. Similar trends were observed when only pts without favorable cytogenetics were analyzed. In multivariable models, the NCR/ACR groups were significant predictors for OS (P=0.02), DFS (P=0.01) and CIR (P=0.03). The relative risk of relapse or death for ACRs was 2.0 - 2.2 times that of NCRs (95%CI: 1.1–1.2 to 3.8–4.3 depending on endpoint). Conclusions: Our data suggest that reverting to a normal karyotype at time of 1st CR is an important prognostic factor and support the use of cytogenetic remission (CRc) as a criterion for CR in AML. No significant financial relationships to disclose.

Since t(8;21) and inv(16) disrupt core binding factor in AML and confer a favorable prognosis, these cytogenetic groups are often treated similarly, but hitherto have not been compared in a large study. We compared 144 adult AML patients (pts) with t(8;21) with 168 with inv(16) enrolled on the cytogenetic study CALGB 8461. t(8;21) pts were less frequently white (P=.01), had lower hemoglobin levels (P=.03), WBC (P<.001) and % blood (P<.001) and BM blasts (P=.005), and had more frequently secondary chromosome aberrations (P<.001) than inv(16) pts, who more often had extramedullary disease (P<.001). Pts were induced with cytarabine/daunorubicin (AD) or cytarabine/daunorubicin/etoposide ±PSC833(ADE±P). Complete remission (CR) was achieved by 89% of t(8;21) and 87% of inv(16) pts. Upon multivariable analysis (MVA), non-white race (P=.006), lower platelets (P=.01) and higher BM blasts (P=.004) predicted negatively for CR in t(8;21), and lower platelets (P=.009) and hepatomegaly (P=.04) in inv(16) pts. Non-whites with t(8;21) had 5.7 times the odds of not achieving CR as whites. For the entire group (median follow-up 6.4 yrs), the estimated 5-yr overall survival (OS) and cumulative incidence of relapse (CIR) were 51% and 53%, respectively. Pts with t(8;21) showed a trend for shorter OS (46% vs 54%; P=.17) but no difference in CIR compared with inv(16) pts. Upon MVA, t(8;21) pts had worse OS than inv(16) pts (HR 1.5; P=.04), once adjusting for age, platelets, and WBC. Following first relapse, the 5-yr survival of t(8;21) pts (n=58) was shorter than that of inv(16) pts (n=74) (14% vs 36%; P=.01); in an age-adjusted model, the risk of death was 1.8 times higher for t(8;21) pts (P=.005). In a subanalysis of pts <60 yrs, consolidation therapy with multi-course high-dose cytarabine (HDAC x3 or 4) significantly decreased CIR compared to single-course HDAC (x1) in t(8;21) (5-yr CIR, 35% vs 64%; P=.005) and inv(16) (5-yr CIR, 44% vs 70%; P =.03) pts. Upon MVA, consolidation with multi-course HDAC reduced CIR for both t(8;21) and inv(16), but other prognostic factors differed (see Table). For t(8;21), induction with ADE±P and higher platelets increased risk of relapse. However, relatively few pts received ADE±P so its prognostic impact requires confirmation. For inv(16), +22 and other secondary cytogenetic aberrations, and male sex were favorable prognostic factors.

Cytogenetic analysis has become an integral part of diagnosis and prognostication of acute myeloid (AML) and acute lymphoblastic leukemia (ALL). Consequently, CALGB mandates cytogenetic analyses for adult AML and ALL first-line treatment trials and many correlative studies. It is thus imperative that cytogenetic data are accurate. To this end, CALGB has performed central review of karyotypes (CRK) submitted by CALGB approved institutional cytogenetics laboratories since 1985. In this study, we have evaluated the role of CRK in ensuring that high quality cytogenetic data are available to CALGB researchers using two criteria: 1) the proportion of specimens deemed on CRK to be of sufficient vs insufficient quality to be included in the CALGB database (ie, accepted vs rejected according to the criteria published by Byrd et al, Blood2002;100:4325–4336), and 2) among the accepted cases, the proportion of submitted karyotypes whose interpretation was changed during CRK. In our analyses, we excluded samples studied cytogenetically during complete remission, because they differ from pretreatment and relapse samples in that they rarely contain leukemic cells and usually are karyotypically normal. Overall, 18% of AML and 35% of ALL karyotypes submitted were not accepted (Table). The most common reason for rejecting a karyotype on CRK was inadequate banding quality, which accounted for rejection in 41% of AML and 34% of ALL inadequate cases. The quality of the submitted karyotypes, measured by the proportion of rejected cases, has improved significantly in both AML and ALL since 1986. However, CRK in 2001–2003 still found 12% of AML and 26% of ALL samples inadequate. Among karyotypes deemed adequate, we analyzed in detail revisions made during the 2001–2003 CRK. Changes in karyotype interpretation were made in 26% of AML and 25% of ALL cases. The revisions included identification or reinterpretation, other than reassignment of breakpoints, of the chromosome abnormality (seen in 52% of samples with karyotype errors), a misidentified or upside down chromosome(s) (34%), reassignment of breakpoints in structural aberrations recognized by the submitting laboratory (28%) and correction of errors in the ISCN (1995) nomenclature (15%). Examples of clinically relevant changes in karyotype interpretation included revisions of a normal karyotype to an abnormal one that harbored inv(3)(q21q26), t(9;11)(p22;q23), t(11;19)(q23;p13.1), or inv(16)(p13q22), change from del(11)(q23) to t(6;11)(q27;q23), etc. Overall, 35% of AML and 45% of ALL samples submitted were either rejected or revised on CRK. We conclude that although we observed an improvement in quality of cytogenetic analyses over time, central review of karyotypes still plays a vital role in ensuring the success of the clinical trials and correlative studies conducted by cooperative groups.

6543 Background: AML with t(6;11)(q27;q23) is a well established but rare entity, and few reports describe full clinical, hematological, and outcome data of these patients (pts). Methods: We searched the CALGB database comprising 2667 adults with newly diagnosed de novo AML, enrolled from 1984 to 2003, and identified 16 (0.6%) pts with t(6;11). Literature review identified 40 previously published cases of t(6;11) adult de novo AML with treatment outcome data available. Results: CALGB pts had a median age of 45 years (range, 22–65); 8 were men. t(6;11) was the sole abnormality in 69% of pts. Pts commonly (81%) presented with French-American-British subtype M4 or M5. Gingival hypertrophy and high white blood cell count (>50 x109/l) were relatively frequent, each occurring in 5 (31%) pts. t(6;11) pts were more likely to be African-American (p=0.02) and to die during induction (p=0.03) than all other de novo AML pts without t(6;11). The complete response (CR) rate was 69% (11/16 pts); all 5 remaining pts died during induction. CR duration was short (median 8.5 months). Median overall survival (OS) was 10.7 months, and the estimated probability of 2-year survival was 13%. Both long-term survivors received allogeneic SCT, one in first CR and one after relapse. Two pts (one from CALGB, one from literature) are known to have had allogeneic SCT in first CR; both were long-term survivors. The table describes all t(6;11) AML cases with outcome data available. Conclusion: While patient numbers are small, early allogeneic SCT should be considered for adults with de novo t(6;11) AML who achieve CR, as the window of opportunity before relapse and death appears to be short. No significant financial relationships to disclose.

Secondary cytogenetic abnormalities at diagnosis of Philadelphia chromosome-positive (Ph+) chronic myelogenous leukemia (CML) have been associated with an inferior outcome in reported series of largely chemotherapy-treated patients. To date, no study has specifically focused on the prognostic significance of secondary karyotypic abnormalities, detected at the time of diagnosis, in interferon (IFN)-alpha treated patients. We compared the outcome of 29 newly diagnosed Ph+ CML patients with additional abnormalities to that of 234 sole Ph+ patients, treated on CALGB protocols with IFN-alpha alone or together with IFN-gamma or low-dose cytarabine. Complete and partial cytogenetic responses were achieved in 20 and 19% of sole Ph+ patients, compared to 23 and 18%, respectively, of patients with additional abnormalities (P=1.00). None of 4 patients with 'high-risk' secondary abnormalities [+8, +Ph and i(17)(q10)], for whom follow-up cytogenetic samples were available, achieved a cytogenetic response. With a median follow-up of 11.3 years, the median overall survival (OS) was 6.0 years for sole Ph+ patients compared to 7.5 years for patients with additional abnormalities (P=0.70), with corresponding 8-year OS of 36 and 38%, respectively. On multivariable analysis, only age (P<0.001) and white blood cell count (P=0.02) were associated with outcome. We conclude that, with the possible exception of +8, +Ph and i(17)(q10), additional chromosomal abnormalities at diagnosis are not associated with inferior outcome in Ph+ CML patients treated with IFN-alpha-based therapy.

Ring chromosome 17 is a rare cytogenetic abnormality, with 12 previous reports in the literature. Some have a relatively mild phenotype characterized by seizures, mental retardation, skin changes and short stature. Other patients have Miller–Dieker syndrome (MDS), which includes lissencephaly, multiple dysmorphic features, severe mental retardation and shortened life expectancy.We describe two new cases of ring chromosome 17 and review the literature. Our cases and the other reports of patients without a deletion encompassing the Miller–Dieker region, delineate a fairly distinctive subgroup of individuals with ring 17, whose phenotype consists of growth and mental retardation, seizures, minor dysmorphic features, café‐au‐lait spots and retinal flecks. This classification of ring 17 into two distinct groups based on the size of the deletion and the phenotypic manifestations should facilitate clinical suspicion of this rare chromosomal abnormality.

A 39-year-old male underwent a nonmyeloablative stem cell transplant (NMAPBPCT) from his HLA-matched sister for recurrent anaplastic large cell lymphoma in CR-2, receiving fludarabine, cyclophosphamide, and rabbit antithymocyte globulin for the preparative therapy. The patient was readmitted on day+33 for persistent culture-negative fevers. He rapidly developed marked elevations of alkaline phosphatase and bilirubin. Liver biopsy showed a periportal infiltrate of large immunoblastic appearing cells. The tumor cells did not stain for CD3/CD20/CD30 and alk protein, but did stain for CD79a/LCA and CD43. In situ hybridization for Epstein-Barr virus (EBV) RNA (EBER 1) was strongly positive in the periportal infiltrating lymphocytes. Fluorescence in situ hybridization (FISH) studies revealed female (XX) cells in the tumor cells and male (XY) in the surrounding hepatic parenchymal cells. The patient developed severe lactic acidosis, oliguric renal failure and expired on day+44. Both donor and patient had positive IgG serologies for EBV VCA and EBNA pretransplant. The donor also had a positive IgM titer for EBV VCA in the pretransplant specimen. The LPD may have been related to the intense immunosuppression of the preparative therapy and the presence of recent EBV infection in the donor.

Osteosarcomatous transformation in fibrous dysplasia is unusual. The incidence is increased in patients with concomitant Mazabraud's syndrome and McCune-Albright syndrome. We report the cytological, histological, and cytogenetic findings of this rare entity arising from a mass in the right elbow of a 44-year-old African-American woman. The fine-needle aspiration (FNA) findings were diagnostic of malignancy, with markedly atypical spindle and polygonal cells admixed with osteoid. The diagnosis of osteosarcoma by FNA was subsequently further confirmed by histological evaluation of an above-elbow amputation specimen. Fluorescence in situ hybridization and comparative genomic hybridization demonstrated trisomies of chromosomes 5 and 7 in the fibrous dysplasia and osteosarcoma. In addition, multiple chromosomal abnormalities were also noted in the osteosarcoma. We are unaware of any previous reports of the cytogenetic findings in the tissue of this rare condition, and argue for the value of FNA in the evaluation of such patients under selected conditions.

SOAT1, SOAT2 (also known as ACAT1 and ACAT2) and DGAT1 belong to the acyl-CoA: cholesterol acyltransferase gene family, members of which esterify cholesterol in Kupffer (SOAT1) and hepatic cells (SOAT2, DGAT1) of the liver (Lee et al. 2000; Buhman et al. 2001). Non-human primates fed monounsaturated fat responded with induction of SOAT2 enzyme activity in the liver, resulting in increased levels of cholesteryl ester containing lipoproteins in plasma followed by development of atherosclerosis (Rudel et al. 2002). Absence of SOAT2 reduced plasma concentrations of cholesteryl ester levels and the incidence of atherosclerosis in knockout mice (Willner et al., 2003). It is not established whether absence of one or more of these enzymes has a similar protective effect in primates. We localized the three genes for lipid esterification in this gene family to chromosomes of two Old World monkeys: Macaca fascicularis (macaque, MFA), Cercopithecus aethiops sabaeus (African green monkey, CSA) and a New World monkey Saimiri sciureus sciureus (Squirrel monkey, SSC). Each of these species has been used as a model for diet-induced atherosclerosis as occurs in humans (HSA) (Rudel and Lofland, 1976; Rudel et al., 2002). Materials and methods

We analyzed prospectively 1213 adults with de novo acute myeloid leukemia (AML) to ascertain the prognostic impact of cytogenetic abnormalities on complete remission (CR) rate, 5-year cumulative incidence of relapse (CIR), and 5-year overall survival (OS). All patients received similar induction therapy. Median follow-up for surviving patients was 8.3 years. Nonprioritized cytogenetics distinguished t(8;21) and inv(16)/t(16;16) as conferring a significantly better prognosis than normal karyotype. Prognostic impact of many abnormalities could not be determined independently because of their association with complex karyotype. Neither complex karyotype nor secondary aberrations affected outcome of patients with t(8;21), inv(16)/t(16;16), or t(9;11). Among other patients, those with complex karyotypes had significantly worse outcomes than cytogenetically normal patients. Based on outcome for specific cytogenetic abnormalities and karyotype complexity, patients were divided into 3 risk groups: favorable (CR 88%, CIR 54%, OS 55%), intermediate (CR 67%, CIR 67%, OS 24%), and adverse (CR 32%, CIR 92%, OS 5%). Multivariate analyses confirmed the major contribution of cytogenetics to the probability of attaining CR, CIR, and OS. For the adverse-risk group, the probability of achieving CR was 4.0 and 11.9 times lower, the probability of relapse 3.0 and 4.4 times higher, and the risk of death 2.1 and 4.3 times higher than those for the intermediate and favorable groups, respectively. We conclude that although the prognostic impact of many recurring abnormalities has not been ascertained independently of complex karyotype, cytogenetics is among the most useful factors predicting attainment of CR, CIR, and long-term survival in adult AML.