Pediatric Oncology Group experience with modified LSA2-L2 therapy in 107 children with non-Hodgkin's lymphoma (Burkitt's lymphoma excluded)

6-thioguanine: a drug with unrealized potential for cancer therapy

Sixty years ago, 6-thioguanine (6-TG) was introduced into the clinic. We suggest its full potential in therapy may not have been reached. In this paper, we contrast 6-TG and the more widely used 6-mercaptopurine; discuss 6-TG metabolism, pharmacokinetics, dosage and schedule; and summarize many of the early studies that have shown infrequent but nevertheless positive results with 6-TG treatment of cancers. We also consider studies that suggest that combinations of 6-TG with other agents may enhance antitumor effects. Although not yet tested in man, 6-TG has recently been proposed to treat a wide variety of cancers with a high frequency of homozygous deletion of the gene for methylthioadenosine phosphorylase (MTAP), often codeleted with the adjacent tumor suppressor CDKN2A (p16). Among the cancers with a high frequency of MTAP deficiency are leukemias, lymphomas, mesothelioma, melanoma, biliary tract cancer, glioblastoma, osteosarcoma, soft tissue sarcoma, neuroendocrine tumors, and lung, pancreatic, and squamous cell carcinomas. The method involves pretreatment with the naturally occurring nucleoside methylthioadenosine (MTA), the substrate for the enzyme MTAP. MTA pretreatment protects normal host tissues, but not MTAP-deficient cancers, from 6-TG toxicity and permits administration of doses of 6-TG that are much higher than can now be safely administered. The combination of MTA/6-TG has produced substantial shrinkage or slowing of growth in two different xenograft human tumor models: lymphoblastic leukemia and metastatic prostate carcinoma with neuroendocrine features. Further development and a clinical trial of the proposed MTA/6-TG treatment of MTAP-deficient cancers seem warranted.

Lymphoma in adolescents and young adults

Non-Hodgkin (NHL) and Hodgkin (HL) lymphomas are represented prominently in the adolescent and young adult (AYA) population. These diseases represent 11% of total cancer diagnoses in children, 4% in those 40 years of age and older, and 13% in AYA (aged 15-39 years). Although age-adjusted incidence rates of NHL increase with age, the more aggressive lymphomas are seen more commonly in the younger population with a transition to low-grade, indolent subtypes as the population ages. Burkitt lymphoma, diffuse large B-cell lymphoma, lymphoblastic lymphoma, and anaplastic large cell lymphoma make up the most common subtypes in the AYA population, although within the subgroup age 30-39 years, follicular lymphoma becomes more prominent. As a result, much of the armamentarium in the treatment of aggressive NHL and HL in adults is based on data from pediatric clinical trials. There are obvious limitations to this approach. It is vital that we gain a more thorough understanding of the biology and therapeutic responsiveness of NHL and HL in the AYA population. Thus, we must leverage the large prospective and retrospective trials that have been completed to date and redirect our approaches to cancer care in this unique population. We review the epidemiological data on NHL and HL from the Surveillance, Epidemiology and End Results registries as a cornerstone for a comparative analysis of therapeutic outcomes available in this population.

Minimal disseminated disease in childhood T-cell lymphoblastic lymphoma: a report from the children's oncology group

PURPOSE Disease dissemination to the bone marrow is detected at diagnosis in approximately 15% of children with T-cell lymphoblastic lymphoma (T-LL). It is unclear whether the remaining patients have submicroscopic systemic disease and, if so, what is the clinical significance of this finding. PATIENTS AND METHODS Using a flow cytometric method that can detect one T-LL cell among 10,000 normal cells, we examined bone marrow and peripheral-blood samples collected from 99 children with T-LL at diagnosis, as well as blood samples collected from 42 patients during treatment. Results In 71 (71.7%) of the 99 marrow samples obtained at diagnosis, T-LL cells represented 0.01% to 31.6% (median, 0.22%) of mononuclear cells; 57 of the 71 T-LL-positive samples were from patients with stage II/III disease. Results of studies in bilateral marrow aspirates were highly concordant. Two-year event-free survival (EFS) was 68.1% +/- 11.1% (SE) for patients with > or = 1% T-LL cells in bone marrow versus 90.7% +/- 4.4% for those with lower levels of marrow involvement (P = .031); EFS for patients with > or = 5% lymphoblasts was 51.9% +/- 18.0% (P = .009). T-LL cells were as prevalent in blood as in marrow; monitoring residual T-LL cells in blood during remission induction therapy identified patients with slower disease clearance. CONCLUSION More than two thirds of children with T-LL have disseminated disease at diagnosis, a proportion much higher than previously demonstrated. Measurements of disease dissemination at diagnosis might provide useful prognostic information, which can be further refined by monitoring response to therapy through blood testing.

Combination of dexamethasone, high-dose cytarabine, and carboplatin is effective for advanced large-cell non-Hodgkin lymphoma of childhood

BACKGROUND

The purpose of the current study was to evaluate the activity and toxicity of dexamethasone, high-dose cytarabine, and carboplatin (DAC) combination therapy in children with newly diagnosed large-cell non-Hodgkin lymphoma (NHL) and to estimate the event-free and overall survival rates achieved when DAC is incorporated into a conventional regimen.

METHODS

From 1991 to 1997, 20 boys and 5 girls aged 4.2 to 17.7 years who had stage III (according to the St. Jude staging system) (n = 21) or stage IV (n = 4) large-cell NHL were treated in this study. DAC therapy was administered at the beginning of the induction phase in 2 sequential cycles and incorporated throughout a continuation phase (modified from the ACOP+ regimen, which features doxorubicin, cyclophosphamide, vincristine, and prednisone) with doxorubicin, cyclophosphamide, vincristine, and dexamethasone. The total duration of treatment was approximately 10 months.

RESULTS

DAC therapy yielded a response in 22 of 25 patients (88%; 95% confidence interval [95% CI], 68%-97%): complete remission in 13 cases (52%), and partial response in 9 (36%). After additional treatment with doxorubicin, cyclophosphamide, vincristine, and dexamethasone, complete remission was attained in 18 patients (72%) and partial remission in 3 (12%). The event-free survival rate (+/- the standard error [SE]) was 64% +/- 9% and the overall survival rate was 80% +/- 8% at 5 years.

CONCLUSIONS

The results of the current study indicate that the DAC regimen is well tolerated and effective for pediatric patients with large-cell NHL.

Lymphoblastic lymphoma of childhood and the LSA2-L2 protocol: the 30-year experience at Memorial-Sloan-Kettering Cancer Center

BACKGROUND

Until the 1970s, diffuse lymphoblastic lymphoma (DLBL) was considered incurable. With intensive multidrug regimens, the majority of patients can now be cured. In the current study, the authors present what to their knowledge is the longest follow-up presented to date (median, 20 years for survivors) of the largest group of DLBL patients treated with a single protocol at a single institution.

METHODS

Between 1971-1990, a total of 95 consecutive patients (age < 21 years) with DLBL were treated with the LSA(2)-L(2) protocol at the Memorial Sloan-Kettering Cancer Center (MSKCC). Patients with Stage I-II disease were treated for 2 years. In 1980, the protocol was modified and patients with Stage III and IV disease were treated for 3 years. In addition, before the modification, patients with Stage IV disease received a cumulative dose of 15,600 mg/m(2) of cyclophosphamide for 3 years; after 1980, these patients received the same dosage as the other patients (i.e., 8400 mg/m(2) for 2 years). Radiation therapy initially was administered to all patients with bulky disease in the primary tumor site. Until 1977, the dose of radiation was 20-55 grays (Gy); from 1977 to 1989, the dose was 20 Gy. After the fifth year of completion of treatment, all patients were evaluated comprehensively every 2 years.

RESULTS

The overall survival (OS) of the patients was 79% with a median follow-up of 20 years. The overall event-free survival (EFS) was 75% (71 of 95 patients). Seventeen patients developed a disease recurrence and 15 died of disease. The OS and EFS rates for patients with Stages I-II disease (n = 8) were 87% and 87%, respectively, and the OS and EFS rates for patients with Stage III disease (n = 41) were 90% and 85%, respectively. The OS and EFS for patients with Stage IVA disease (with bone marrow [BM] involvement of < 25%) (n = 19) were 79% and 73%, respectively, whereas the OS and EFS for patients with Stage IVB disease (BM involvement of > 25%) (n = 27) were 74% and 70%. Of the 29 patients with Stage IV disease who were treated with the original protocol, 7 died of disease (1 of 8 patients with Stage IVA disease and 6 of 21 patients with Stage IVB disease). Of the 17 patients with Stage IV disease who were treated with the modified protocol, 3 died of disease (2 of 11 patients with Stage IVA disease and 1 of 6 patients with Stage IVB disease). Six patients developed secondary malignancies, four of whom died.

CONCLUSIONS

Long-term EFS can be achieved in the majority of patients with widely disseminated pediatric DLBL. Chemotherapy alone appears to be sufficient prophylaxis against disease recurrence in the central nervous system. No disease-related or treatment-related deaths were reported to occur > 4.5 years after diagnosis in the current study.

Lymphoblastic lymphoma

Recent advances in the unique clinicopathologic entity of lymphoblastic lymphoma (and its variants) are discussed in this article, which details the natural history, molecular biology, prognosis, and outcome with various chemotherapy regimens. Improved outcome with the newer intensive chemotherapy regimens and the role of modalities such as autologous intensification, allogeneic bone marrow transplant, and radiotherapy are discussed.

Cost analysis of filgrastim for the prevention of neutropenia in pediatric T-cell leukemia and advanced lymphoblastic lymphoma: a case for prospective economic analysis in cooperative group trials

BACKGROUND

Growth factor use has been shown to ameliorate chemotherapy-induced neutropenia, leading to shorter hospital stays and lower use of parenteral antibiotics, two costly areas of cancer treatment. Prior reports on pediatric patients have shown evidence of cost savings in some studies, but no such evidence in others. In this study a retrospective analysis compared the costs of inpatient supportive care for pediatric patients with T-cell leukemia and advanced lymphoblastic lymphoma enrolled in a Pediatric Oncology Group trial.

PROCEDURE

Patients 1-22 years of age were randomized to receive either granulocyte colony-stimulating factor (G-CSF; n = 45) or no G-CSF (n = 43) following induction and two cycles of maintenance therapy. There were no significant differences in neutropenia-related outcomes during the induction phase. During maintenance therapy, G-CSF patients had significantly fewer days to an ANC >500 cells/microl and a trend towards fewer days of hospitalization. Data on resource utilization were tabulated from case report forms. Costs were imputed from national data on hospitalization costs, average wholesale prices of pharmaceuticals, and patient billing information from a single institution.

RESULTS

Total median costs of supportive care were $34,190 for patients receiving G-CSF and $28,653 for patients not receiving G-CSF (P > 0. 05 for the cost difference). Sensitivity analyses demonstrated that the total cost difference was not statistically significant, even in scenarios that included reasonable variations in estimates of the range of the length of stay, antibiotic regimen, and dosage and cost of G-CSF.

CONCLUSIONS

In the setting of pediatric leukemia, the cost of growth factor may offset potential savings from shorter hospital stays or lower antibiotic use, a finding consistent with that from the Children's Cancer Study Group.

Large cell non-Hodgkin lymphoma of childhood: Analysis of 78 consecutive patients enrolled in 2 consecutive protocols at the Memorial Sloan-Kettering Cancer Center

BACKGROUND

The authors report a study of pediatric patients with advanced diffuse large cell lymphoma (DLCL) who were treated with 2 consecutive regimens, LSA2-L2 and LSA4, over a 25-year-period at the Memorial Sloan-Kettering Cancer Center. They also describe a comparative analysis of two subgroups retrospectively identified as having CD30 positive (+) anaplastic large cell lymphoma (ALCL) and CD30 negative (-) DLCL. To the authors' knowledge, this study represents the longest follow-up on the largest series of uniformly treated pediatric DLCL patients reported to date.

METHODS

A total of 78 consecutive patients were treated for Stage III/IV DLCL. Immunophenotypic data were obtained retrospectively for 52 patients using a panel of monoclonal antibodies against CD30, CD15, CD45, CD45Ro, CD43, epithelial membrane antigen, CD5, BCL-2, cyclin-D, and p53.

RESULTS

A disease free survival rate of 72% in patients with advanced stage DLCL using the LSA2-L2 and LSA4 regimens. Of the 78 treated patients, 56 are alive and without evidence of disease with a median follow-up of 120 months (range, 24-312 months). The recurrence rate was significantly higher in the CD30+ ALCL subgroup (33%) than in the CD30- DLCL group (0.04%). Of 52 patients for whom immunophenotypic data were available, 28 had disease of B-cell lineage, 24 had disease of T-cell/null phenotype, 19 were CD30+ (36. 5%), 18 had disease of T-cell phenotype, and 1 had disease of B-cell lineage.

CONCLUSIONS

The CD30- DLCL cases mostly were of B-cell lineage, had a small risk of treatment failure, and did not develop a recurrence off therapy. A distinct clinical pattern was identified for the CD30+ ALCL group; although these tumors were of T-cell lineage and had a significantly higher rate of late recurrences (median follow-up of 24 months) they all were salvageable. Based on the findings of the current study, the authors propose that T-cell CD30+ ALCL be addressed in the future according to equal dose intensity regimens in induction therapy, as is done for B-cell lymphomas; prolonged periods of maintenance chemotherapy, as is done for T-cell lymphoblastic lymphomas; and no central nervous system prophylaxis beyond the induction period unless other recognized risk factors are present.

Precursor B-cell lymphoblastic lymphoma presenting as an orbital mass

A previously healthy 12-year-old boy presented with acute onset of proptosis of his left eye. CT scan demonstrated a mass involving the left orbit, left maxillary sinus, and left ethmoid sinus with extension through the cribriform plate into the anterior cranial fossa. Incisional biopsy of the mass revealed a precursor B-cell lymphoblastic lymphoma. Precursor B-cell lymphoblastic lymphoma is a rare type of non-Hodgkin's lymphoma seen exclusively in children and young adults. This is the first reported case of precursor B-cell lymphoblastic lymphoma presenting in the orbit. Treatment is primarily by systemic chemotherapy and is potentially curative. The principal role of the ophthalmologist is in diagnosis and monitoring of such patients. The clinical features and multidisciplinary diagnosis and management of childhood non-Hodgkin's lymphomas are reviewed.

Non-Hodgkin's lymphoma in children: disease pattern and survival

The use of intensive chemotherapy and incorporation of prophylactic treatment of the central nervous system have dramatically improved the outcome of children with non-Hodgkin's lymphoma (NHL). The authors analyzed retrospectively the disease characteristics and survival data of 34 children with NHL during a 7-year period. There were 26 boys and 8 girls with a median age of 8 years. The primary sites were the abdomen (41%) and peripheral node (41%). Histopathologically lymphoblastic and undifferentiated lymphoma (small nonclaved cell lymphoma) were equally distributed (41%). Thirteen patients had localized disease (stage I and II) and 21 patients had advanced disease (stage III and IV). Surgical removal of the primary tumor was done in 6 patients with localized gastrointestinal lesions. All 34 patients received chemotherapy, either cyclophosphamide, vincristine, methotrexate, and prednisolone (COMP) or adriamycin, cyclophosphamide, vincristine, and prednisolone (ACOP). Thirty patients achieved complete remission (88.2%). The 5-year event-free survival rate was 64%. The results indicate that most children with localized disease can be cured by COMP chemotherapy, but more aggressive chemotherapy is necessary to improve survival in advanced-stage disease.

Favorable outcome after 1-year treatment of childhood T-cell lymphoma/T-cell acute lymphoblastic leukemia

BACKGROUND

For T-malignancies in children a poor prognosis is reported. In these malignancies a combination of lymphoma and leukemia is commonly seen at presentation and most patients are treated according to protocols for acute lymphoblastic leukemia (ALL). These protocols are often designed for the majority of ALL cases, i.e., progenitor-B-ALL. In pediatric lymphoblastic non-Hodgkin's lymphoma without bone marrow infiltration various protocols have been used. The most frequently reported regimens show variable survival rates between 40 and 75%.

PATIENTS AND METHODS

From 1989 we have treated 32 consecutive patients with T-cell malignancies, irrespective of localization, with a protocol consisting of a 4-agent induction treatment followed by high doses of methotrexate, and cytosine-arabinoside and intensified bleomycin, adriamycin, cyclophosphamide, vin cristin, prednisone (BACOP) courses. Treatment duration for each patient was 1 year. Twenty-one of the 32 patients had stage IV disease. Follow-up ranged from 1.6 to 7.6 years (median 4.2 years).

RESULTS

Overall event-free survival (EFS) was 72%, while in those with stage IV disease it was 67%. No therapy-related deaths occurred. Neither stage, initial leukocyte value, mediastinal involvement, bone marrow involvement, nor the presence of CD1, CD3, CD4, CD8, or CD10 epitopes was prognostically significant. Evaluation of toxicity revealed a minimal decrease of carbon monoxide diffusion and cardiac shortening fraction.

CONCLUSION

A relatively short but intensive chemotherapy can be used in T-cell malignancies. The EFS is satisfying, but larger studies are needed.

Treatment of children and young adults with early-stage non-Hodgkin's lymphoma

BACKGROUND

Children and young adults with early-stage non-Hodgkin's lymphoma have an excellent prognosis, but treatment is prolonged and is associated with many side effects. We performed two studies to determine whether therapy could be simplified.

METHODS

Between 1983 and 1991, we conducted two consecutive trials in children and young adults (age, <21 years) with early-stage non-Hodgkin's lymphoma. In the first trial, patients were treated for 9 weeks with induction chemotherapy consisting of vincristine, doxorubicin, cyclophosphamide, and prednisone, followed by 24 weeks of continuation chemotherapy with mercaptopurine and methotrexate. Half the patients were randomly assigned to receive involved-field irradiation. In the second trial, after the 9 weeks of induction chemotherapy, the patients were randomly assigned to receive 24 weeks of continuation chemotherapy or no further therapy.

RESULTS

A total of 340 patients were enrolled in the two trials, 12 of whom did not have complete remissions. One hundred thirteen patients received nine weeks of chemotherapy without radiotherapy, 131 received eight months of chemotherapy without radiotherapy, and 67 received eight months of chemotherapy with radiotherapy. At five years, the projected rates of continuous complete remission were 89, 86, and 88 percent for the three groups, respectively. At five years, event-free survival among the patients with early-stage lymphoblastic lymphoma was inferior to that among the patients with other subtypes of lymphoma (63 percent vs. 88 percent, P<0.001). Continuation therapy was effective only in patients with lymphoblastic lymphoma.

CONCLUSIONS

A nine-week chemotherapy regimen without irradiation of the primary sites of involvement is adequate therapy for most children and young adults with early-stage, nonlymphoblastic non-Hodgkin's lymphoma.

Non-Hodgkin's lymphoma

Pediatric lymphomas are the third most common group of malignancies in children and adolescents. Unlike lymphomas in adults, pediatric lymphomas are diffuse, aggressive neoplasms with a propensity for widespread dissemination. Intensification of conventional treatment approaches along with improvements in supportive care have resulted in dramatic improvement in event-free survival rates of close to 90% in patients with B-cell lymphomas and only slightly lower in patients with T-cell lymphomas. Lymphoid neoplasms arise because of genetic changes that result in altered growth and differential patterns of lymphoid cells. The characterization of these molecular abnormalities and an understanding of their consequences has led to new approaches to diagnosis and the detection of minimal residual disease and also provides the basis for the future development of novel treatment approaches targeted specifically to the neoplastic cells.

Management of paediatric lymphoma

The high cure rate obtained in most paediatric lymphomas allows an optimistic vision of future treatments, with decreased primary late effects observed in patients who have completed therapy: decreased cognitive functional impairment, reproductive dysfunction, poor social adaptation, and risk of second malignancies. The deleterious effects of radiation therapy on neurocognitive functions is now well documented (Meadows et al, 1981) but, apart from rare acute toxicities (Sasazaki et al, 1992), reports on those following high-dose methotrexate are scarce, and sometimes discordant (Jannoun and Chessels, 1987; Robertson et al, 1992). Longer follow-up evaluation is warranted before definitive conclusions concerning the relationship between computed tomography scan findings and clinical outcome can be reached. The reproductive function of males is much more severely altered than that of females (Jaffe et al, 1988). Several reports have demonstrated the major dose-dependent toxicity of alkylating agents on male fertility. Male patients receiving more than 9 g/m2 of cyclophosphamide have a particularly high risk of sterility (Aubier et al, 1989) and children with less than 4 g/m2 of cyclophosphamide, a very low risk Patte et al, 1996a). Women treated before the age of 20 who do not receive abdominal irradiation usually have normal reproductive function, although early puberty (Quigley et al, 1989) and early menopause (Byrne et al, 1992) have been documented. The risk of a second malignancy is not as great as in children with a solid tumour or Hodgkin's disease (Anderson et al, 1993). The risk is higher in patients treated with alkylating agents (Lemerle et al, 1989). With the increasing cure rate, a social problem may arise for adults who "have had cancer'. The increased awareness by politicians and health insurance companies should help to solve, at least partially, this new problem (Monaco, 1987). As cure rates increase, emerging concerns involve the familial repercussions of this heavy treatment (Lansky et al, 1978; Cairns et al, 1979). At this stage, there is no demonstrated deleterious effect from treatment for the progeny of cured children (Mulvihill et al, 1987; Stein, 1993). Cure of children with lymphoma is a reality, and one should think in terms of "complete cure' when facing a distressed child with a heavy tumour burden arriving for diagnosis (Schweisguth, 1979). Since 1980, the progress of molecular biology techniques has permitted the precise molecular characterization of gene alterations (oncogenes, immunoglobulins, and T-cell receptor genes) involved in the process of malignant transformation of normal lymphocytes (Bhatia et al, 1996; Williams et al, 1996). In parallel, treatment of malignant NHL of childhood has improved dramatically. The progress in molecular biology has not led to a modification of the clinical management of NHL of childhood which remains mainly empirical. Precise cytohistological classification of lymphomas has resulted in the characterization of low- and high-risk patients requiring distinct therapeutic approaches. The major goals of the next few years will be to increase the cure rates of those patients with CNS and bone marrow involvement at diagnosis, probably through an intensification of chemotherapy (increase in the dose or intensity of the chemotherapy); to define precisely subgroups of good-prognosis patients requiring less aggressive treatment that would decrease the risk of long-term events; and to salvage previously heavily treated patients at relapse. The precise analysis of gene alterations in lymphoma cells of a given patient may have important clinical applications in this respect (Bhatia et al, 1996).

Treatment of high-risk acute lymphoblastic leukemia in children using the AL851 and ALHR88 protocols: a report from the Kyushu-Yamaguchi Children's Cancer Study Group in Japan

A total of 125 children, who were diagnosed as having high-risk acute lymphoblastic leukemia (ALL), were treated with two consecutive protocols designated as AL851 (1985-1988) and ALHR88 (1988-1990). All patients received induction therapy consisting of vincristine (VCR), prednisolone (PSL), daunorubicin (DNR), and I-asparaginase (I-Asp). In the ALHR88 protocol, the patients whose blasts in the bone marrow (BM) were > or = 25% on day 14 of induction therapy and who were classified into T-cell type received additional cytosine arabinoside (AraC). After consolidation with intermediate-dose methotrexate (MTX), reinduction therapy including VCR, dexamethasone, and adriamycin followed by high-dose AraC was done for all patients. Intrathecal MTX and 24Gy of cranial irradiation were used to prevent central nervous system leukemia. A maintenance therapy consisting of 6-mercaptopurine, cyclophosphamide, MTX, DNR, VCR, and AraC was administered for 3 years after achieving a complete remission (CR). CR was achieved in 51/55 (92.7%) for AL851 and 68/70 (97.1%) for ALHR88. The 5-year event-free survival rates were 49.1 +/- 6.7% in AL851 and 62.5 +/- 6.1% in ALHR88. The factors related to a poor prognosis were a high initial leukocyte count of greater than 50 x 10(9)/L (P < 0.001), an L2 morphology of leukemic cells by FAB classification (P = 0.009), the chromosomal abnormality (P = 0.004) and high residual leukemic cells in BM (> or = 25%) on day 14 of induction therapy (P < 0.001). Taking these factors into consideration, more intensive protocols were started in 1990 for the patients with high-risk ALL.

Childhood NHL in Switzerland: incidence and survival of 120 study and 42 non-study patients

Based on the Swiss Pediatric Oncology Group (SPOG) cancer registry data during 1981-1991, a high average incidence of 8 new NHL per million children younger than 15 years per year was found. Of 162 children with NHL registered in 1976-1991, 120 were study patients, i.e., officially registered and treated according to SPOG or Pediatric Oncology Group (POG) protocols, while 42 were non-study patients, i.e., patients not officially enrolled on protocols. Overall, 91 of 120 (76%) study patients remained alive. Seventy-nine study patients were treated according to older SPOG protocols, and 53 (67%) of these survived, while 38 of 41 (93%) study patients treated according to newer POG protocols remained alive (P = 0.0068). Only 22 (52%) of the 42 non-study patients survived (P = 0.0001). There was no improvement if the survival of non-study patients before and since 1986 was compared. Population-based treatment results in Switzerland were similar to those in the United Kingdom. They provided an important base for the development of future treatment strategies.

Stage III abdominal non-Hodgkin's lymphoma in Costa Rican children: comparison of two consecutive trials of treatment

Seventy-three patients with Stage III abdominal non-Hodgkin's lymphoma were prospectively treated following two sequential protocols (P): L278 P (group A, 33 patients) (1978-1983) and L384 P (group B, 40 patients), (1984-1991). No patient received radiotherapy. The L278 P included 7 drugs: cyclophosphamide, vincristine (VCR), adriamycin (ADR), prednisone, methotrexate (MTX), dexamethasone, and 6-mercaptopurine, given for remission induction, maintenance, and CNS prophylaxis. In the L384 P we introduced a consolidation phase consisting of intravenous MTX and citrovorum factor rescue, and IV cytosine arabinoside. VCR was also added to the monthly doses and the maintenance phase was reduced from 18 to 15 months. From January 1988 we changed ADR for epirubicin in the same doses. Prophylactic treatment of the CNS, in the L384 P, was intensified by increasing the number of doses of MTX IT in the remission, induction, and consolidation phases, and with the use of ara-C IT. Laparotomy in 50 patients allowed partial resection in 16, and second-look laparotomy was performed in 27 patients. Viable tumor was found in four patients. Three patients (G-A) died from metabolic complications and another 4 (2 G-A and 2 G-B) failed to attain CR and died. A total of 28 (85%) of 33 children of G-A and 38 (95%) of 40 children in G-B achieved CR. Five children died in remission (2 G-A, 3 G-B). Three patients (G-A) relapsed in the CNS and one (G-B) relapsed in the abdomen and died. Disease-free survival at 120 months was 70% in G-A and 84% in G-B.

Factors contributing to the prognostic significance of bone marrow involvement in childhood non-Hodgkin lymphoma

To evaluate the clinical characteristics and treatment outcome of childhood non-Hodgkin lymphoma (NHL) cases with bone marrow involvement, we studied 13 lymphoblastic, 15 small noncleaved cell, and 8 large cell cases with tumor cells in their marrow. They represented 16%, 11%, and 9% of consecutive NHL cases with these respective histologic subtypes. The treatment outcome differed significantly according to histologic subtype--the 5-year event-free survivals (EFS +/- SE) for large cell NHL, small non-cleaved cell NHL, and lymphoblastic NHL cases were 11 +/- 8%, 40 +/- 20%, and 62 +/- 15%, respectively. Increased serum lactate dehydrogenase (LDH) levels (> 500 U/L) were associated with a poorer EFS (5-year EFS, 0% vs. 50 +/- 10%; P < 0.001). Children < or = 5 years of age had a poorer EFS survival than older children (5-year EFS, 14 +/- 9% vs. 44 +/- 10%; P = 0.03). The degree of bone marrow involvement (< 5% vs. > or = 5%) and race were not significantly associated with treatment outcome. Although intensive chemotherapy has substantially improved survival for patients with advanced stage lymphoblastic or small noncleaved cell lymphoma, patients with large cell NHL and associated marrow involvement continue to have a dismal outcome and require novel or more intensive therapy.

Disseminated nonlymphoblastic lymphoma of childhood: a Childrens Cancer Group study, CCG-552

PURPOSE

To assess the efficacy of a chemotherapy-only regimen in pediatric patients with disseminated non-lymphoblastic lymphoma and acute B-cell leukemia (B-ALL).

PATIENTS AND METHODS

Sixty-eight eligible patients with previously untreated disseminated non-lymphoblastic lymphoma were enrolled on a Childrens Cancer Group study. Therapy included cycles of chemotherapy, systemic and intrathecal (IT), ever 3 weeks for a total maximal duration of 57 weeks. Fifty-five patients had small non-cleaved cell lymphoma (SNCCL) and 13 had diffuse large cell lymphoma (DLCL). Forty-seven were stage III, six were stage IV, and 15 had B-ALL; 13 had central nervous system (CNS) involvement.

RESULTS

Four year event-free survival (EFS) was 53% (SE +/- 12%). Stage III SNCCL patients with LDH < 500 IU/L achieved an improved EFS compared to other SNCCL patients (86% vs. 42% 4 year EFS, P = .072). The primary site of failure for advanced stage SNCCL patients was the CNS. All Ki-1-positive DLCL patients relapsed. Patterns of failure, time to relapse, and outcome following relapse differed between SNCCL and DLCL patients.

CONCLUSIONS

Advanced stage SNCCL requires better CNS-directed chemotherapy to reduce the CNS failure rate; however, the achievement of durable disease-free survival in four of 11 patients with CNS disease without use of cranial irradiation suggests merit for further evaluation of chemotherapy-only strategies. DLCL patients do not need intensive CNS-directed chemotherapy.

Non-Hodgkin's lymphomas in children. II. Treatment

The prognosis of non-Hodgkin's lymphoma (NHL) in childhood has improved steadily in the last 2 decades. This is primarily the result of increasingly effective chemotherapy regimens tailored to defined and relatively homogeneous prognostic categories and tested in prospective clinical trials. Surgical excision remains of prognostic benefit only when near-total resection can be performed without delay of chemotherapy. The role of radiation therapy is now limited to the treatment of overt central nervous system (CNS) lymphoma, disease unresponsive to chemotherapy, and certain emergencies. Effective 'prophylactic' treatment of the CNS has been achieved in most series by intrathecal and systemic chemotherapy alone. The most relevant modality of treatment is chemotherapy and a very large number of protocols have been published. The origins of current multi-agent regimens stem both from early experience with cyclophosphamide in endemic Burkitt's lymphoma and from therapeutic studies of acute lymphoblastic leukaemia. Sub-stratification of non-localized NHL has produced protocols designed for either lymphoblastic (mostly T cell) or non-lymphoblastic (mostly B cell) categories. While the cure rate for lymphoblastic lymphoma now exceed 70%, the non-localized non-lymphoblastic disease remains a major obstacle to cure. These patients frequently present with large abdominal primaries and are prone to regional as well as hematogenous dissemination. In particular, involvement of the CNS is now considered to be the most adverse prognostic variable in this group. Recently, highly intensive regimens are addressing these obstacles. On the other hand, NHL defined as localized has been shown to be curable in up to 95% of children with the use of simple chemotherapy regimens as short as 6 months in duration. Salvage of patients who relapse during or after chemotherapy remains bleak but cures are possible with regimens incorporating bone marrow transplantation from either an autologous or allogeneic source. Experimental methods, including biologic and immune response modifiers may also offer future promise.

Results of the LMT81 protocol, a modified LSA2L2 protocol with high dose methotrexate, on 84 children with non-B-cell (lymphoblastic) lymphoma

From May 1981 to June 1989, 84 children with non-B-cell lymphoma (82 lymphoblastic, 1 T-cell immunoblastic, 1 unclassified diffuse lymphoma) were treated in the pediatric department of the Institut Gustave Roussy according to a protocol called LMT81, which was derived from the LSA2L2 protocol of Wollner and modified by the adjunction of 10 courses of high dose methotrexate to improve the CNS prophylaxis. No planned irradiation was performed except in cases of initial tests (2 patients) or CNS (5 patients) involvement and residual mass (2 patients). Sixty patients had mediastinal involvement; for the others, primaries were in the head and neck (7), nodes (2), (sub)cutaneous (4), bone (7), and elsewhere (2). According to Murphy's staging system, there were 2 stage I, 6 stage II, 33 stage III, and 43 stage IV. Among the stage IV patients, 41 had bone marrow involvement, 24 of them with more than 25% blast cells in bone marrow and 19 with blast cells in blood; 7 had CNS involvement. Three patients did not achieve complete remission, 4 died in remission (two measles, one post-transfusion AIDS, one unexplained definitive aplasia) and 13 relapsed at 2 to 29 months (median-13 months). Among the 77 patients without initial CNS involvement, there was only one isolated CNS relapse. With a median follow-up of 57 months (10-106 months), the event-free survival is 75% (SE 2.5) for the 84 patients with a plateau at 29 months, 73% (SE 8) for stage I and II patients, 79% (SE 4) for stage III, and 72% (SE 4) for stage IV patients. Survival was similar in each stage group. Reasons for failure of treatment, however, were different, being toxic deaths in stage II; initial therapy resistance, early relapses, and toxic deaths in stage III; and tumor failures in stage IV. In conclusion, this protocol is efficacious on T and non-T, non-B childhood lymphoma with a low incidence of CNS relapse. A future study will seek to diminish toxicity and long-term sequellae while at least maintaining the same cure rate of patients.

Poor prognosis of mediastinal non-Hodgkin's lymphoma with an immature phenotype of CD2+, CD7 (or CD5)+, CD3-, CD4-, and CD8-

Nine children with mediastinal non-Hodgkin's lymphoma (NHL) were treated according to our new regimen which is characterized by intensified therapy with high-dose cytosine arabinoside (HDCA). After induction therapy with a combination of five drugs, such as vincristine, doxorubicin, cyclophosphamide, 1-asparaginase, and prednisolone, intermediate dosages of methotrexate (MTX) (1 g/m2) and HDCA (1.5 g/m2 x 12 doses) were administered. All but one patient (88.9%) achieved complete remission and then received this intensified therapy. With a median follow-up period of 25.5 months, five patients are still in complete remission, but three patients have relapsed. From the phenotypic point of view, these relapsed patients showed only very immature T-cell differentiation antigens such as CD2 and CD7 (or CD5). These results suggest that HDCA as intensified therapy for children with mediastinal NHL seems to be effective. However, for patients with an immature phenotype of T-lineage cells, more sophisticated regimens should be prepared.

Non-Hodgkin's lymphomas

The non-Hodgkin's lymphomas are a group of diseases for which substantial progress has been made in understanding tumor biology and effectiveness of treatment during the last few years. These advances may provide insight into the development of neoplasms because of recognized association of lymphomas with viral infections and immunodeficiency. The prognosis for patients with non-Hodgkin's lymphomas continues to improve. As a result, current studies on treatment of lymphomas in certain favorable stages have concentrated on reducing the intensity of therapy. For patients with advanced disease, further improvements in treatment are being sought.

Combined chemotherapy in 76 children with non-Hodgkin's lymphoma excluding Burkitt's lymphoma

From January 1983 to December 1986 seventy-six previously untreated children with non-Hodgkin's lymphoma (NHL) were treated by combination chemotherapy. Burkitt's lymphoma patients were ineligible. The treatment regimens include intermittent chemotherapy and for non-localized patients, prophylactic central nervous system chemotherapy. Intrathoracic non-Hodgkin's lymphoma patients also had cranial prophylactic radiotherapy. Sixty-six patients (86.8%) achieved complete remission. Two year failure-free survival rate was 82.1% for localized (stage I and II) NHL and 53.3% for non-localized (stage III and IV) NHL patients. Failure-free survival did not differ significantly for the two major histologic diagnoses, but two year survival rate was lower in diffuse poorly differentiated lymphoblastic than undifferentiated non-Burkitt's lymphoma (50% versus 66.8% respectively). Failure-free survival rate was 53.7% in mediastinal disease and, 73.2% in abdominal disease at 24 months. Relapse rate was higher in mediastinal cases (46.1%) than primary abdominal cases (24.3%) at 24 months. Eleven (13.5%) died of treatment related sepsis. Although the overall survival rate was 72.4% at 2 years we need novel or more intensive programmes for mediastinal and non-localized disease.

A morphologic study of childhood lymphoma of the lymphoblastic type. The pediatric Oncology Group experience

For this study 227 non-Hodgkin's lymphomas, registered through the Pediatric Oncology Group clinical studies between 1976 and 1982, were morphologically subclassified into major histologic types and subtypes, and their histopathologic and clinical features were compared. These lymphomas were distributed primarily into only three of the recognized major histologic types: lymphoblastic (LB), 106 (47%); undifferentiated (DU), 49 (21%); and diffuse histiocytic (DH), 72 (32%). These patient groups were found to differ in several ways: the LB lymphomas contained most of the patients under two years of age; the LB lymphomas tended to present in higher clinical stages; the LB lymphomas tended to involve lymph node groups and the bone marrow more often than did the DU and DH lymphomas; and the DU lymphomas had a greater tendency for gastrointestinal tract and other major organ system involvement. The complete remission rate of 96%, for the LB lymphomas was better than for either the DU or the DH lymphomas. The disease-free survival of the LB lymphomas was significantly better than the DU group, but not the DH group. The LB were histologically divisible into three subtypes: convoluted (C), nonconvoluted (NC), and large cell variant (LCV). The C and NC subtypes preferentially involved the mediastinum and peripheral lymph nodes initially, while the LCV tended to involve the abdomen. However, none of the subtypes differed in clinical stage. The complete remission, and the disease-free survival rates between these subtypes were not statistically different.

Indications for and benefits of intensive therapies in treatment of childhood cancers

There has been a striking improvement in the overall numbers of children and adolescents who become disease-free and remain disease-free as a result of intensive therapy as defined today, for the following cancers: acute nonlymphocytic leukemia (ANLL), non-Hodgkin's lymphoma (NHL), poor risk acute lymphocytic leukemia (ALL), osteosarcoma, and Ewing's sarcoma. The therapy for each of these tumors, with the exception of osteosarcoma, consisted of combination chemotherapy with or without radiotherapy and was started as soon after diagnosis as possible. Aggressive therapy of osteosarcoma has consisted of surgical removal of lung metastases and chemotherapy. Intensive chemotherapy recently has included the use of high doses of certain drugs such as cytosine arabinoside (Ara-C), methotrexate, VP-16-213 and melphalan in the treatment of patients with tumors that are currently difficult to treat.

Sequential testicular biopsies in childhood acute lymphocytic leukemia

Between August 1978 and November 1981, 33 boys with acute lymphocytic leukemia (ALL) (26 non-T, 7 T-cell) younger than 16 years underwent bilateral wedge testicular biopsies at the time of initial diagnosis. Seven (4 non-T, 3 T-cell) demonstrated focal leukemic infiltrates. Rebiopsy after successful induction therapy without testicular irradiation showed eradication of leukemic infiltrates in five, persistent focal infiltrates in one, and a diffuse infiltrate in one. The two patients who had persistent leukemic involvement had a T-cell phenotype, and in one of them overt testicular disease developed 2 years later. All 33 patients were followed prospectively for a minimum of 3 years. Fifteen (14 non-T, 1 T-cell) remained in remission for 3 years and underwent another testicular biopsy before the cessation of therapy. Two patients, both non-T and both of whom were free of testicular involvement at diagnosis, showed testicular infiltrates at that time. Of the seven boys with positive specimens at diagnosis, only two remained disease-free for 3 years and showed no testicular involvement upon the completion of chemotherapy. In this study, microscopic testicular involvement by lymphoblasts occurred in 21% of newly diagnosed boys with ALL; this occurred only if the leukocyte count exceeded 25,000/microliter. These patients in general had a poor prognosis, probably reflecting the overall heavy tumor burden. However, it was not possible to predict accurately those patients who would have leukemic testicular infiltrates at the cessation of chemotherapy by performing biopsy of the testes at the time of initial diagnosis or after induction therapy.

Childhood non-Hodgkin's lymphoma and "leukemia-lymphoma syndrome": long-term results with the modified LSA2-L2 protocol

From June 1976 to December 1984, 48 previously untreated children with non-Hodgkin's lymphoma (NHL) were treated according to the LSA2-L2 protocol, modified by inclusion of cranial irradiation for patients in stage III and stage IV disease. According to the staging system proposed by Wollner, 4 patients were in stage I, 8 in stage II, 11 in stage III, 8 in stage IVA (less than or equal to 25% blasts in the bone marrow), 15 in stage IVB (greater than 25% blasts in the bone marrow), and 2 in stage IV central nervous system disease. The complete remission rate was 95.8%. The relapse-free survival (RFS) rate of 46 complete responders was 76% after a median observation time of 47+ months. Only 1 of 35 high-risk responder patients developed CNS relapse after prophylactic treatment. Clinical stages were related to the RFS: 100% in stage I-II vs. 69% in stage III-IV. All 8 patients in stage IV were alive without evidence of disease with a median observation time of 59+ months. Fifteen patients in stage IVB who had leukemia-lymphoma syndrome attained 59% RFS with a median observation time of 39+ months. After a median observation time of 38+ months, 29 of 37 patients are off therapy. The results emphasize the value of both the histologic and immunologic features and the stage of disease in predicting the outcome of NHL in children. The LSA2-L2 regimen appears to be a very effective protocol for children with lymphoblastic lymphoma, although it may be less efficacious for patients with large bone marrow involvement.

Effectiveness of a six-drug regimen (APO) without local irradiation for treatment of mediastinal lymphoblastic lymphoma in children

Fourteen children with mediastinal lymphoblastic lymphoma (MLL) were treated with the six-drug APO protocol. This regimen includes aggressive intermittent chemotherapy and prophylactic central nervous system therapy. Mediastinal irradiation was given only for emergency relief of mediastinal compression (two children) or for incomplete resolution of mediastinal widening with chemotherapy (one child). All 14 patients achieved complete remission; only 1 has relapsed. Toxicities were not severe. APO is effective therapy for children with MLL. APO should receive further trials in children and adults with T-cell lymphoblastic lymphomas.