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J T Sandlund

Publications and source records attributed to J T Sandlund.

At least 91 records · Page 5Linked to original sources
PubMed1994

11q23/MLL rearrangement confers a poor prognosis in infants with acute lymphoblastic leukemia.

PURPOSE: Leukemic cell characteristics were analyzed in infants less than 1 year of age with acute lymphoblastic leukemia (ALL) to determine adverse prognostic factors that might explain the poor prognosis of this group. PATIENTS AND METHODS: Treatment outcomes were analyzed according to the presenting clinical and laboratory features of 30 infants treated between May 1979 and April 1993. A stepwise multivariate regression model was used to identify the most important prognostic indicator with respect to event-free survival. RESULTS: Infant ALL cases were characterized by high presenting leukocyte count (median, 87 x 10(9)/L), increased frequency of CNS leukemia (50%), and blast cells with a CD10- phenotype (67%), myeloid-associated antigen expression (48%), and 11q23/MLL rearrangement (68%). The 11q23/MLL involvement was correlated with age less than 6 months, CD10- phenotype, myeloid-associated antigen expression, and high leukocyte count. Although 11q23/MLL involvement, age less than 6 months, myeloid-associated antigen expression, and female sex were each significantly associated with an inferior treatment outcome, only rearranged 11q23/MLL emerged as an independent predictor of prognosis in multivariate analysis (P = .01). Infants with this genetic abnormality had a 4.7-fold (95% confidence interval, 1.3- to 17.0-fold) increased risk in adverse events compared to other infants. CONCLUSION: The 11q23/MLL involvement of blast cells identifies a major subgroup of infant ALL cases that require an innovative treatment approach. Infants who lack this genetic abnormality have an intermediate prognosis and could be treated accordingly on risk-directed protocols.

Chromosome Aberrations↗
PubMed1994

Large cell non-Hodgkin lymphoma of childhood: clinical characteristics and outcome.

Less is known about the clinical features and treatment outcome in pediatric large cell non-Hodgkin lymphoma (NHL) than the lymphoblastic and small noncleaved cell subtypes of NHL. To characterize presenting features and assess possible risk factors associated with this diagnosis, we analyzed data for 91 patients treated on a succession of multiagent regimens from 1975 to 1990. Five-year event-free survival (EFS) (+/- SE) was related to disease extent (St Jude system): stage I (n = 24), 95% +/- 5%; stage II (n = 20), 84% +/- 9%; stage III (n = 38), 50% +/- 10%; and stage IV (n = 9), 22% +/- 11%. Advanced stage disease, age < or = 5 years and serum LDH > 500 U/l were associated with poorer EFS in the univariate model (p < 0.001, 0.005, and 0.002, respectively). In the multivariate model, advanced stage and age retained prognostic significance (p = 0.001 and 0.02, respectively), but LDH did not. Among limited stage cases, age < or = 5 years was the only adverse risk feature (p = 0.016); treatment era (pre- vs. post-1979) was the only significant feature in patients with advanced disease (p = 0.004). Intrathoracic primaries were associated with a better outcome than other sites among the 38 stage III patients (p = 0.005). Only one of eight patients with bone marrow disease remains failure-free. The excellent results for limited stage pediatric large cell NHL permit consideration of treatment modifications to decrease toxicity; for cases with advanced disease, especially those with bone marrow involvement, novel therapeutic approaches are clearly needed.

Adolescent↗
PubMed1993

Clinical significance of CD34 expression in childhood acute lymphoblastic leukemia.

The CD34 antigen was detected on > or = 10% of the blast cells in 235 (70%) of 335 cases of newly diagnosed childhood acute lymphoblastic leukemia (ALL) treated in two consecutive chemotherapy trials. By immunophenotype, the distribution of positive cases favored early pre-B ALL (83%; n = 180) followed by pre-B ALL (61%; n = 89) and then T-cell ALL (46%; n = 61) (P < .001). Among the B-lineage cases, CD34 expression was significantly associated with favorable presenting features: age 1 to 10 years, white race, absence of central nervous system (CNS) leukemia, low serum lactate dehydrogenase level, CD10 expression, and leukemic cell hyperdiploidy (> 50 chromosomes or DNA index > or = 1.16). Event-free survival was clearly superior for patients with CD34+ leukemia (P = .01), with an estimated 83% +/- 6% (SE) of the cohort remaining free of adverse events at 5 years post diagnosis, as compared to 63% +/- 10% of the group without this feature. Multivariate analysis showed that the prognostic influence of the antigen was independent of age, leukocyte count, and other well-recognized factors, suggesting that it would add discriminatory power to current systems of risk assignment. Findings in T-cell ALL were the reverse: CD34 expression showed positive correlations with initial CNS leukemia and CD10 negativity but not with any good-risk presenting characteristics. Log-rank analysis indicated no adverse effect on treatment outcome by CD34 antigen expression, although additional patients with need to be studied to obtain a definitive answer. The opposed clinical associations of CD34 expression in B- and T-lineage ALL may reflect fundamental biologic differences between these leukemia species.

Antigens, CD↗
PubMed1993

Low leukocyte counts with blast cells in cerebrospinal fluid of children with newly diagnosed acute lymphoblastic leukemia.

BACKGROUND: Treatment of the central nervous system is crucial to the successful treatment of acute lymphoblastic leukemia in children. The intensity and timing of the therapy are based on the presence or predicted risk of central nervous system leukemia as assessed according to criteria that remain controversial. METHODS: The clinical importance of leukemic blast cells detected in cerebrospinal fluid at the time of diagnosis was evaluated in 351 children with acute lymphoblastic leukemia in a randomized trial of intensive chemotherapy. All patients received intrathecal chemotherapy during the first year. Patients considered to be at high risk of relapse because of their clinical and cytogenetic features also received cranial irradiation and intrathecal chemotherapy one year after remission. Patients were considered to have central nervous system leukemia at diagnosis if they had at least 5 leukocytes per microliter of cerebrospinal fluid, with leukemic blast cells apparent in cytocentrifuged preparations, or cranial-nerve palsy; they received additional intrathecal injections of chemotherapeutic agents and cranial irradiation. Patients were retrospectively classified on the basis of cerebrospinal fluid findings: 291 patients had no detectable blast cells, 42 had fewer than 5 leukocytes per microliter and blast cells, and 18 had central nervous system leukemia as defined above. The clinical characteristics and outcomes of treatment in these groups were analyzed. RESULTS: The five-year probability of survival free of relapses confined to the central nervous system in patients with detectable blast cells and fewer than 5 leukocytes per microliter of cerebrospinal fluid was lower than in patients without blast cells (mean [+/- SE], 87 +/- 13 vs. 96 +/- 2 percent), but was not different from the probability in patients with central nervous system leukemia at diagnosis. All such isolated relapses of leukemia in patients with detectable blast cells occurred during the first year of treatment, before scheduled cranial irradiation. In a multivariate analysis, the presence of cerebrospinal fluid blast cells with fewer than 5 leukocytes per microliter was independently related to the risk of relapse confined to the central nervous system. CONCLUSIONS: Patients with leukemic blast cells in their cerebrospinal fluid are at increased risk for central nervous system relapse when cranial irradiation is delayed. Such patients require intensified central nervous system treatment early in the course of therapy.

Adolescent↗
PubMed1993

Progress in the treatment of adolescents with acute lymphoblastic leukemia.

UNLABELLED: BACKGROUND AND METHODS. The authors studied the clinical and biologic features and treatment response of 358 children with acute lymphoblastic leukemia (ALL), including 90 adolescents, treated on a single multiagent protocol (St. Jude Total Study XI, 1984-1988). This was done to clarify whether the disease differed in adolescents and to determine the degree of improvement in treatment outcome produced by this modern intense chemotherapy. RESULTS: Compared with the younger children (1-9 years of age; infants 1 year old or younger excluded; n = 257), adolescents (10-18 years of age; n = 90) were significantly more likely to have adverse prognostic features, including T-cell phenotype, L2 blast cell morphologic characteristics, blasts with negative findings for common ALL antigen, and ploidy other than hyperdiploidy greater than 50. Eighty-six of the 90 (96%) adolescents achieved a complete remission, a rate similar to that of the children (97%). Although the event-free survival (EFS) of adolescents was shorter than that of younger children (5-year EFS of 66 +/- 8% versus 75 +/- 5%, respectively; P = 0.04), in this analysis of consecutively treated patients with ALL it showed a significant statistical and clinical improvement as compared with that in our previous study (St. Jude Total Study X, 1979-1983; 5-year EFS rate of 66 +/- 8% versus 37 +/- 5%, respectively; P < 0.001). Within the adolescent group treated on Total Study XI, the EFS was worse for those older than 15 years of age than for those 10-14 years old (46 +/- 15% versus 75 +/- 8%, respectively; P = 0.007). Toxic effects primarily included myelosuppression without severe sequelae. Approximately 96% of the therapy was administered in the outpatient setting. CONCLUSIONS: The increased frequency of unfavorable clinical and biologic features undoubtedly accounts for the poorer prognosis of adolescents with ALL, a conclusion supported by the lack of independent prognostic importance of age in this study. The authors conclude that approximately two-thirds of adolescents can be cured when treated with this intensive but tolerable therapy, showing that this form of treatment significantly has changed the prognosis of adolescents with ALL.

Adolescent↗
PubMed1993

Theophylline induced differentiation provides direct evidence for the deregulation of c-myc in Burkitt's lymphoma and suggests participation of immunoglobulin enhancer sequences.

Most of the evidence that supports the hypothesis that the c-myc gene is abnormally regulated in Burkitt's lymphoma (BL) is indirect. The putative abnormal expression of c-myc is likely, at least in part, to be a consequence of the usurpation of its regulatory sequences by immunoglobulin enhancer elements, which are invariably juxtaposed to c-myc by the translocations associated with this tumor (C. M. Croce, J. Erikson, A. Ar-Rushdi, D. Aden, and K. Nishikura, Proc. Natl. Acad. Sci. USA, 81: 3170-3174, 1984). We have developed a differentiation induction model system to examine this issue more directly. In a variety of non-BL cell lines, differentiation induction results in the down-regulation of c-myc (G. P. Studzinski, A. K. Bhandal, and Z. S. Brelvi, Proc. Soc. Exp. Biol. Med., 179: 288-295, 1985; Y. Matsui, R. Takahasi, K. Minara, T. Nakagawa, T. Koizumi, Y. Nakao, T. Sugiyama, and T. Fugita, Cancer Res., 49: 1366-1371, 1985; T. Mitchell, E. Sariban, and D. Kufe, Mol. Pharmacol., 30: 398-402, 1986; Z. S. Brelvi, and G. P. Studzinski, J. Cell. Physiol., 128: 171-179, 1986). Since BL is of B-cell origin, differentiation is associated with persistent or increased expression of immunoglobulin genes. Therefore, if c-myc and c-mu are coregulated in BL via immunoglobulin enhancer sequences, persistent or increased expression of the c-myc gene, rather than down-regulation, should occur in differentiated BL cells. Differentiation was induced in four BL cell lines with theophylline (7 x 10(-3) M), and mRNA was examined by Northern blot analysis. In all four BL lines studied (JD38, AG876, KK124, and Daudi), there was persistent or increased expression of both c-mu and c-myc genes (detected with a third exon c-myc probe), in contrast to the decreased expression of the c-myc gene observed in the three Epstein-Barr virus transformed lines studied (A3317, TC84, and CB34). In the BL cell line, JD38, the c-myc gene is truncated (the second and third exons are translocated to chromosome 14 while the first exon remains on chromosome 8). In this line, we demonstrated that theophylline induced differentiation results in down-regulation of the first exon while the level of expression of the translocated second and third exons remains unchanged or increases.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1993

Pharmacokinetics and acute renal effects of continuously infused carboplatin.

Carboplatin was given as a 24-hour infusion at high doses to pediatric patients with cancer (n = 11) and pharmacokinetic parameters and renal effects were determined. Median carboplatin clearance for course 1 (151 ml/min per 1.73 m2;) was not significantly different from clearance for course 2 (144 ml/min per 1.73 m2; p = 0.33). The median glomerular filtration rate measured before (159 ml/min per 1.73 m2) and after course 1 (161 ml/min per 1.73 m2) did not differ significantly (p = 0.4). Binding was time dependent but modest with a median free fraction at the end of infusion of 0.82. Pharmacokinetic parameters for continuous-infusion carboplatin are similar to those reported for short infusions, but the median dose of 817 mg/m2 required to achieve an acceptable systemic exposure in these patients was 45% greater than the previously suggested maximum tolerated dosage. Continuous infusion carboplatin did not alter carboplatin clearance or adversely effect glomerular filtration rate during a second course, showing the feasibility of this alternative dosage strategy to enhance therapeutic effects.

Adolescent↗
PubMed1993

MACOP-B treatment in children and adolescents with advanced diffuse large-cell non-Hodgkin's lymphoma.

From 1986 through 1990, 13 previously untreated pediatric patients with advanced diffuse large-cell non-Hodgkin's lymphoma (LC-NHL) were treated with a 12-week MACOP-B regimen at St Jude Children's Research Hospital. Although 12 patients (92%) achieved a complete response, and one had a partial response, the 2-year event-free survival was only 54 +/- 15% (SE). Seven patients remain in continuous complete remission at a median of 40 months after therapy (range 23-57 months). Relapses occurred at sites of initial involvement in five patients at a median of 3.0 months after remission (range 1.2-8.5 months). Salvage therapy with radiation, and high-dose chemotherapy and bone marrow transplantation produced four durable second remissions. The 2-year overall survival for the entire group is 84 +/- 10% (SE). The 12-week MACOP-B regimen proved feasible in an ambulatory clinic setting with only minimal toxicity. We found that MACOP-B is an effective and tolerable treatment for pediatric patients with LC-NHL but did not provide improved survival over that of a similar group of children treated in previous trials at this institution.

Adolescent↗
PubMed1993

Clinical significance of CD10 expression in childhood acute lymphoblastic leukemia.

The independent significance of CD10 expression in childhood acute lymphoblastic leukemia (ALL) is uncertain because most studies have not adjusted for other risk features, such as age and immunophenotype, or for treatment effects. We reassessed the clinical importance of CD10 expression in patients who received highly effective contemporary treatment. CD10 antigen was detected in blast cells from 384 of 408 patients (94%) with B-lineage ALL and 36 of 90 (40%) with T-cell ALL. In the B-lineage subgroup, CD10 expression was associated with favorable presenting features: age > or = 1 year, lower leukocyte count (< 50 x 10(9)/l), and leukemic cell DNA index > or = 1.16 or hyperdiploidy > 50 chromosomes. One-half of the patients with CD10- B-lineage ALL had 11q23 chromosomal abnormalities. Separate analysis of the marker in T-cell ALL revealed no differences between CD10+ and CD10- cases in clinical features or karyotypic patterns, with the exception of a lower frequency of central nervous system leukemia and a higher frequency of 9p abnormalities in the former subgroup. CD10+ T-cell cases were also significantly more likely than CD10- cases to coexpress CD21, CD1, CD4, or CD8. Lack of CD10 expression was independently associated with an adverse prognosis in T-cell ALL (p = 0.02). However, for the larger subgroup of patients with B-lineage ALL, CD10 expression has no independent prognostic significance.

Burkitt Lymphoma↗
PubMed1992

Update of St Jude Study XI for childhood acute lymphoblastic leukemia.

We treated 358 children with non-B-cell acute lymphoblastic leukemia with intensive multiagent chemotherapy (St. Jude Study XI) in a risk-directed study which used very intensive induction and consolidation therapy followed by continuation treatment comprised of rotating drug pairs given for the entire duration of therapy (except for a third of lower-risk patients). CNS irradiation was reserved for a subset of patients at higher risk of treatment failure. All patients received triple intrathecal chemotherapy (hydrocortisone, ara-C, methotrexate) for prevention of CNS leukemia. At a median follow-up of almost 5 years (all patients are off therapy for 8 months or more), the estimated 5-year event-free survival rate is 72% +/- 4%. The isolated CNS relapse rate is 5% and there has been only a single testicular relapse. The high incidence of secondary acute myeloid leukemia which we previously associated with use of epipodophyllotoxins were highly associated with a single treatment regimen featuring 6 consecutive weeks of epipodophyllotoxin therapy. Study XI was significantly more effective than all previous St. Jude Total Therapy studies (especially for higher risk patients), could be delivered mostly in the outpatient setting, and, except for a single regimen, was largely free of serious side effects.

Acute Disease↗
PubMed1992

Childhood malignant non-Hodgkin lymphomas of uncommon histology.

Uncommon histologies were identified in 36 of 1336 cases (2.7%) of newly diagnosed childhood non-Hodgkin lymphoma (NHL). Seventeen cases were classified as follicular (six cases as mixed small and large cell, nine as large cell, and two as small non-cleaved cell) and 19 cases as diffuse (18 cases as mixed small and large cell, and one as small cell lymphocytic). The follicular pattern group included a preponderance of male patients; the median age at diagnosis was 11.7 years. These children presented primarily with low-stage disease involving lymph nodes or tonsils. All patients except one achieved complete remission and remain disease-free for 11 months to 18.8 years (actuarial 5-year event-free survival, 94%). The group with diffuse histologies was similar in sex ratio, age at diagnosis (median = 12.1 years), and nodal involvement, but tended to have more advanced-stage disease. Moreover, only 14 of 19 (74%) children with diffuse intermediate-grade histologies are alive in continuous complete remission (actuarial 5-year event-free survival, 70%). These results suggest that follicular pattern childhood NHL has an excellent prognosis, whereas cases with diffuse intermediate-grade histology are prognostically similar to those with diffuse high-grade histologies.

Adolescent↗
PubMed1991

Acute myeloid leukemia in children treated with epipodophyllotoxins for acute lymphoblastic leukemia.

BACKGROUND AND METHODS: Treatment of cancer with the epipodophyllotoxins (etoposide and teniposide) has been linked to the development of acute myeloid leukemia (AML) in children and adults, but the factors that might influence the risk of this complication of therapy are poorly defined. We therefore assessed the importance of potential risk factors for secondary AML in 734 consecutive children with acute lymphoblastic leukemia who attained complete remission and received continuation (maintenance) treatment according to different schedules of epipodophyllotoxin administration. RESULTS: Secondary AML was diagnosed in 21 of the 734 patients, in 17 of whom this complication was the initial adverse event. Prolonged administration of epipodophyllotoxin (teniposide with or without etoposide) twice weekly or weekly was independently associated with the development of secondary AML (P less than 0.01 by Cox regression analysis). The overall cumulative risk of AML at six years was 3.8 percent (95 percent confidence interval, 2.3 percent to 6.1 percent); but within the subgroups treated twice weekly or weekly, the risks were 12.3 percent (95 percent confidence interval, 5.7 percent to 25.4 percent) and 12.4 percent (95 percent confidence interval, 6.1 percent to 24.4 percent), respectively. In the subgroups not treated with epipodophyllotoxins or treated with them only during remission induction or every two weeks during continuation treatment, the highest cumulative risk was 1.6 percent (95 percent confidence interval, 0.4 percent to 6.1 percent). After adjustment for treatment frequency, there was no apparent relation between the total dose of epipodophyllotoxins and the development of secondary AML. The relative hazard of etoposide as compared with teniposide could not be determined. CONCLUSIONS: The risk of epipodophyllotoxin-related AML depends largely on the schedule of drug administration. Other factors, including the cumulative dose of epipodophyllotoxin, radiotherapy, and the initial biologic features of the leukemic blast cells, do not appear to have critical roles.

Acute Disease↗
PubMed1991

Cranial nerve palsy in childhood acute lymphoblastic leukemia and non-Hodgkin's lymphoma.

Forty-five children with acute lymphoblastic leukemia or non-Hodgkin's lymphoma had cranial nerve palsy (CNP) as a complication of their disease. Twenty-two of these children had CNP initially and 23, at relapse, with or without previous hematologic relapse. Only one of the 23 patients with CNP at relapse was a long-term survivor. In contrast, 11 of the 22 children who had CNP initially survived in remission for 3+ months to 13+ years. Two factors are associated with an improved outcome for patients with CNP at diagnosis: treatment after 1979 (P less than 0.004) and male gender (P less than 0.01). Patients who received radiation therapy fared better than those for whom radiation was not given (disease-free survival at 2 years 53% versus 29%). The authors conclude that CNP signifies an aggressive or advanced disease requiring intensive systemic chemotherapy and that the role of irradiation should be examined for this group of patients.

Child↗
PubMed1991

Clinical significance of histology and immunophenotype in childhood diffuse large cell lymphoma.

To correlate the histologic subtype of diffuse large cell (DLC) lymphoma with immunophenotype, clinical features, and treatment outcome, 88 consecutively diagnosed children with this disease were studied. Of these cases, 42 (48%) were immunoblastic (IB), polymorphous subtype; 17 (19%) IB, plasmacytoid; 8 (9%) IB, clear cell; 6 (7%) IB, not otherwise specified; and 15 (17%) DLC-follicular center cell (DLC-FCC) type. Of 34 cases successfully phenotyped from paraffin sections, 13 were T cell and 9 were B cell; of the remaining cases, 8 were suggestive of T-cell lineage, 3 of B-cell lineage, and 1 of histiocytic differentiation. Although histologic subtype did not correlate with clinical features or outcome, it did correlate with immunophenotype among those cases for which lineage could be unequivocally assigned (5 of 18 IB vs. 4 of 4 DLC cases were B cell; P = 0.02) Immunophenotype was also correlated with stage of disease (11 of 13 T-cell vs. 3 of 9 B-cell cases had stage III-IV disease; P = 0.03). (Stage III includes all primary thoracic tumors; stage IV includes all with central nervous system and/or bone marrow involvement.) Significant prognostic features were clinical stage and era (thus type) of therapy (P less than 0.001). The authors conclude that most cases of large cell non-Hodgkin's lymphoma in children are of IB morphologic type, most frequently of T-cell lineage, and those with T-cell phenotype appeared to have more advanced disease.

Adolescent↗
PubMed1991

Pleural effusion is associated with a poor treatment outcome in stage III small non-cleaved cell lymphoma.

The clinical significance of pleural effusion was assessed in 24 children with unresectable abdominal small non-cleaved cell lymphoma (St. Jude Stage III). Patients were consecutively enrolled and treated on a regimen including high dose fractionated cyclophosphamide and co-ordinated high dose methotrexate and cytarabine. The overall results were excellent, with 20 of 24 patients alive and event-free at a median follow-up of 4 years. Only one of the patients who lacked pleural effusion has relapsed (testicular), even though many had massive disease. In contrast, three of seven patients with pleural effusion have failed treatment (p = 0.02) and subsequently died. Two measures of tumor burden, serum lactic dehydrogenase and, in a subset of patients, interleukin-2-receptor levels, were significantly higher in patients with pleural effusion (p = 0.002 and p = 0.05, respectively). These findings suggest that unresectable abdominal small non-cleaved cell lymphoma associated with pleural effusion should be up-staged and that these patients should receive more intensive chemotherapy.

Abdominal Neoplasms↗
PubMed1991

Extranodal primary tumor site indicates poor prognosis in childhood head and neck non-Hodgkin's lymphomas.

As a result of the diversity of lymphoid structures in the head and neck, we analyzed clinical characteristics and outcomes of 87 consecutive children with non-Hodgkin's lymphoma (NHL) arising in this region to determine if the nodal versus extranodal primary site influences prognosis. Thirty-one children had primary nodal NHL whereas 56 had extranodal NHL. The two groups were similar in the distribution of age, gender, race, serum lactic dehydrogenase levels, and disease stage. However, extranodal tumors were slightly more likely to have small non-cleaved cell histology (32/56 versus 11/31, p = 0.07) than nodal tumors. In a multivariate analysis, extranodal involvement (p = 0.017), advanced stage disease (p = 0.054) and treatment era (p = 0.056) were each significantly associated with a shorter time of event-free survival. Children with extranodal and extralymphatic NHL had an even worse treatment outcome than did others (p = 0.006). The poor prognosis of extranodal involvement was also evident among children with stage I or II NHL. We conclude that extranodal involvement has an adverse influence on treatment outcome in children with NHL arising in the head and neck region.

Adolescent↗
PubMed1990

Heterogeneity of presenting features and their relation to treatment outcome in 120 children with T-cell acute lymphoblastic leukemia.

Presenting features of 120 consecutive children with T-cell acute lymphoblastic leukemia (ALL), representing 15% of all patients diagnosed as having ALL during the study period, were analyzed to determine relationships with treatment outcome. Patients' ages ranged from 1.7 to 18.8 years (median, 10.3 years) and their leukocyte counts from 1.7 to 1,070 x 10(9)/L (median, 100 x 10(9)/L). Central nervous system (CNS) leukemia was present in 12.5% of the cases, a mediastinal mass in 61%, and L2 lymphoblast morphology in 32%. A relatively high proportion of cases, 26%, had normal karyotypes at presentation. Of the cases tested, membrane CD1 expression was found in 38% of cases, CD3 in 33%, CD4 in 50%, CD5 in 94%, CD8 in 55%, and CD10 in 35%. Four presenting features were found to confer an increased risk of treatment failure: age greater than or equal to 15 years, L2 lymphoblast morphology, abnormal karyotype, and membrane CD3 expression. This study illustrates the heterogeneity of presentations of childhood T-cell ALL and suggests that the relative importance of risk factors in ALL differs according to immunophenotype and treatment strategy.

Age Factors↗