Acute myeloid leukemia in patients treated for rhabdomyosarcoma with cyclophosphamide and low-dose etoposide on Intergroup Rhabdomyosarcoma Study III: an interim report

Adult rhabdomyosarcoma combined with acute myeloid leukemia: A case report

BACKGROUND

Rhabdomyosarcoma is a tumor of mesenchymal origin. Secondary leukemia is a complication of previous transformation to other hematologic disorders or is a treatment-related acute myeloid leukemia secondary to cytotoxic chemotherapy or radiation therapy for other malignancies.

CASE SUMMARY

We present the case of a 36-year-old female patient who was diagnosed with rhabdomyosarcoma and acute myeloid leukemia. Further disease progression was observed after multiline chemotherapy. Eventually, the patient suffered cerebral hemorrhage, which resulted in death.

CONCLUSION

The incidence of rhabdomyosarcoma in adults is extremely low, and secondary leukemia caused by rhabdomyosarcoma is even rarer. Secondary leukemia has a very poor prognosis and a low overall survival rate.

Secondary Malignancies after Ewing Sarcoma-Epidemiological and Clinical Analysis of an International Trial Registry

Ewing sarcoma (EwS) represents highly aggressive bone and soft tissue tumors that require intensive treatment by multi-chemotherapy, surgery and/or radiotherapy. While therapeutic regimens have increased survival rates, EwS survivors face long-term sequelae that include secondary malignant neoplasms (SMNs). Consequently, more knowledge about EwS patients who develop SMNs is needed to identify high-risk patients and adjust follow-up strategies. We retrospectively analyzed data from 4518 EwS patients treated in five consecutive EwS trials from the Cooperative Ewing Sarcoma Study (CESS) group. Ninety-six patients developed SMNs after primary EwS, including 53 (55.2%) with solid tumors. The latency period between EwS and the first SMN was significantly longer for the development of solid SMNs (median: 8.4 years) than for hematologic SMNs (median: 2.4 years) (p < 0.001). The cumulative incidence (CI) of SMNs in general increased over time from 0.04 at 10 years to 0.14 at 30 years; notably, the specific CI for hematologic SMNs remained stable over the different decades, whereas for solid SMNs it gradually increased over time and was higher for metastatic patients than in localized EwS patients (20 years: 0.14 vs. 0.06; p < 0.01). The clinical characteristics of primary EwS did not differ between patients with or without SMNs. All EwS patients received multi-chemotherapy with adjuvant radiotherapy in 77 of 96 (80.2%) patients, and the use of radiation doses ≥ 60 Gy correlated with the occurrence of SMNs. The survival rate after SMNs was 0.49, with a significantly better outcome for solid SMNs compared with hematologic SMNs (3 years: 0.70 vs. 0.24, respectively; p < 0.001). The occurrence of SMNs after EwS remains a rare event but requires a structured follow-up system because it is associated with high morbidity and mortality.

Second Malignant Neoplasms in Patients With Rhabdomyosarcoma

Objective

Rhabdomyosarcoma (RMS) is a rare malignant tumor. The main treatment modality is comprehensive with chemotherapy, radiotherapy, and surgery. With the advancement in recent decades, patient survival has been prolonged, and long-term complications are attracting increasing attention among both physicians and patients. This study aimed to present the survival of patients with RMS and analyze the risk factors for the development of a second malignant neoplasm (SMN).

Methods

The Surveillance, Epidemiology, and End Results (SEER) Program 18 registry database from 1973 to 2015 of the National Cancer Institute of the United States was used for the survival analyses, and the SEER 9 for the SMN analysis.

Results

The 5-, 10-, and 20-year overall survival rates of the patients with RMS were 45%, 43%, and 33%, respectively. The risk of SMN was significantly higher in patients with RMS compared to the general population (SIR=1.95, 95% CI: 1.44 – 2.57, p < 0.001). The risk of developing SMN was increased in multiple locations, including the bones and joints (SIR = 35.25) soft tissues including the heart (SIR = 22.5), breasts (SIR = 2.10), male genital organs (SIR = 118.14), urinary system (SIR = 2.36), brain (SIR = 9.21), and all nervous system organs (SIR = 8.59). The multivariate analysis indicated that RMS in the limbs and earlier diagnosis time were independent risk factors for the development of SMN. Patients with head and neck (OR = 0.546, 95% CI: 0.313 – 0.952, p = 0.033) and trunk RMS (OR = 0.322, 95% CI: 0.184 – 0.564. p < 0.001) and a later diagnosis time were less likely to develop SMN (OR = 0.496, 95% CI: 0.421 – 0.585, p < 0.001).

Conclusion

This study describes the risk factors associated with the development of SMN in patients with RMS, which is helpful for the personalized screening of high-risk patients with RMS.

Characteristics and Predictors for Secondary Leukemia and Myelodysplastic Syndrome in Ewing and Osteosarcoma Survivors

PURPOSE

Long-term survivors of Ewing sarcoma (ES) and osteosarcoma may be at risk for therapy-related acute leukemia or myelodysplastic syndrome (t-AL/MDS).

METHODS AND MATERIALS

We retrospectively reviewed the clinicopathologic characteristics of 1071 patients with osteosarcoma (n = 757) and ES (n = 314) who were treated between 1985 and 2014. Multivariable competing risk analysis was used to analyze predictors of t-AL/MDS, including a radiation dose (≥55.8 Gy vs <55.8 Gy) × disease site (pelvis/spine vs other) interaction term. A supplemental nested case-control study was conducted to assess the association between cumulative chemotherapy dose and t-AL/MDS.

RESULTS

The median follow-up for surviving patients was 97 months (range, 0.03-380). Twenty patients developed t-AL/MDS, all of whom received chemotherapy and 15 of whom were treated with radiation therapy. Radiation therapy to ≥55.8 Gy was associated with development of t-AL/MDS (adjusted hazard ratio, 2.89; 95% confidence interval [CI], 1.23-6.80; P = .015), and there was a significant radiation dose × disease site interaction term (adjusted hazard ratio, 6.70; 95% CI, 2.71-16.53; P_interaction < .001). The 5-year cumulative incidence of t-AL/MDS in patients receiving ≥55.8 Gy radiation therapy to the pelvis or spine was 5.0% (95% CI, 0.9-14.9) for osteosarcoma and 10.7% for ES (95% CI, 3.3-23.2). In our nested case-control study, cumulative doses of ifosfamide and etoposide were associated with development of t-AL/MDS.

CONCLUSIONS

Patients with osteosarcoma and ES receiving ≥55.8 Gy of radiation therapy to the pelvis or spine appear to be at increased risk for t-AL/MDS. Treatment with high cumulative doses of chemotherapy may further augment this risk.

Epigenetic Combination Therapy for Children With Secondary Myelodysplastic Syndrome (MDS)/Acute Myeloid Leukemia (AML) and Concurrent Solid Tumor Relapse

Secondary myelodysplastic syndrome (MDS)/acute myeloid leukemia (AML) is a rare but devastating complication of solid tumor treatment involving high-dose topoisomerase II inhibitor and alkylator chemotherapy. For relapsed or elderly MDS and AML patients ineligible for hematopoietic stem cell transplantation, epigenetic therapies, including DNA methyltransferase inhibitors and histone deacetylase inhibitors, have been utilized as palliative therapy, offering a well-tolerated approach to disease stabilization, prolonged survival, and quality of life. Literature on the use of epigenetic therapies for both primary and relapsed disease is scarce in the pediatric population. Here, we report 2 pediatric patients with secondary AML and MDS, respectively, due to prior therapy for metastatic solid tumors. Both patients were ineligible for hematopoietic stem cell transplantation due to concurrent solid tumor relapse, but were treated with the epigenetic combination therapy, decitabine and vorinostat, and achieved stabilization of marrow disease, outpatient palliation, and family-reported reasonable quality of life.

Synchronous Occurance of Acute Myeloid Leukemia and Rhabdomyosarcoma

Metachronous primary distinct tumors are frequently and increasingly encountered in oncology clinical practice of recent times, but synchronous tumours are still a rarity. We report an unusual case of a 2 year old male child who had synchronous occurrence of rhabdomyosarcoma of pelvis and acute myeloid leukemia.Our search of literature suggests that this may be the first reported case of simultaneous occurrence of these two malignancies.

Secondary leukemia associated with the anti-cancer agent, etoposide, a topoisomerase II inhibitor

Etoposide is an anticancer agent, which is successfully and extensively used in treatments for various types of cancers in children and adults. However, due to the increases in survival and overall cure rate of cancer patients, interest has arisen on the potential risk of this agent for therapy-related secondary leukemia. Topoisomerase II inhibitors, including etoposide and teniposide, frequently cause rearrangements involving the mixed lineage leukemia (MLL) gene on chromosome 11q23, which is associated with secondary leukemia. The prognosis is extremely poor for leukemias associated with rearrangements in the MLL gene, including etoposide-related secondary leukemias. It is of great importance to gain precise knowledge of the clinical aspects of these diseases and the mechanism underlying the leukemogenesis induced by this agent to ensure correct assessments of current and future therapy strategies. Here, I will review current knowledge regarding the clinical aspects of etoposide-related secondary leukemia, some probable mechanisms, and strategies for treating etoposide-induced leukemia.

Local control and outcome in children with localized vaginal rhabdomyosarcoma: a report from the Soft Tissue Sarcoma committee of the Children's Oncology Group

BACKGROUND

The local control approach for girls with non-resected vaginal rhabdomyosarcoma (RMS) enrolled onto Intergroup RMS Study Group (IRSG)/Children's Oncology Group (COG) studies has differed from that used at other primary sites by delaying or eliminating radiotherapy (RT) based on response achieved with chemotherapy and delayed primary resection.

PROCEDURES

We reviewed locoregional treatment and outcome for patients with localized RMS of the vagina on the two most recent COG low-risk RMS studies.

RESULTS

Forty-one patients with localized vaginal RMS were enrolled: 25 onto D9602 and 16 onto Subset 2 of ARST0331. Only four of the 39 with non-resected tumors received RT. The 5-year cumulative incidence of local recurrence was 26% on D9602, and the 2-year cumulative incidence of local recurrence was 43% on ARST0331. Increased local failure rates appeared to correlate with chemotherapy regimens that incorporated lower cumulative doses of cyclophosphamide. Estimated 5-year and 2-year failure free survival rates were 70% (95% CI: 46%, 84%) on D9602 and 42% (95% CI: 11%, 70%) on ARST0331, respectively.

CONCLUSIONS

To prevent local recurrence, we recommend a local control approach for patients with non-resected RMS of the vagina that is similar to that used for other primary sites and includes RT. We recognize that potential long-term effects of RT are sometimes unacceptable, especially for children less than 24 months of age. However, when making the decision to eliminate RT, the risk of local recurrence must be considered especially when using a chemotherapy regimen with a total cumulative cyclophosphamide dose of ≤ 4.8 g/m².

The Intergroup Rhabdomyosarcoma Study Group (IRSG): Major Lessons From the IRS-I Through IRS-IV Studies as Background for the Current IRS-V Treatment Protocols

Purpose. To enumerate lessons from studying 4292 patients with rhabdomyosarcoma (RMS) in the Intergroup Rhabdomyosarcoma Study Group (IRSG, 1972-1997).Patients. Untreated patients < 21 years of age at diagnosis received systemic chemotherapy, with or without irradiation (XRT) and/or surgical removal of the tumor.Methods. Pathologic materials and treatment were reviewed to ascertain compliance and to confirm response and relapse status.Results. Survival at 5 years increased from 55 to 71% over the period. Important lessons include the fact that extent of disease at diagnosis affects prognosis. Re-excising an incompletely removed tumor is worthwhile if acceptable form and function can be preserved. The eye, vagina, and bladder can usually be saved. XRT is not necessary for children with localized, completely excised embryonal RMS. Hyperfractionated XRT has thus far not produced superior local control rates compared with conventional, once-daily XRT. Patients with non-metastatic cranial parameningeal sarcoma can usually be cured with localized XRT and systemic chemotherapy, without whole-brain XRT and intrathecal drugs. Adding doxorubicin, cisplatin, etoposide, and ifosfamide has not significantly improved survival of patients with gross residual or metastatic disease beyond that achieved with VAC (vincristine, actinomycin D, cyclophosphamide) and XRT. Most patients with alveolar RMS have a tumor-specific translocation. Mature rhabdomyoblasts after treatment of patients with bladder rhabdomyosarcoma are not necessarily malignant, provided that the tumor has shrunk and malignant cells have disappeared.Discussion. Current IRSG-V protocols, summarized herein, incorporate recommendations for risk-based management. Two new agents, topotecan and irinotecan, are under investigation for patients who have an intermediate or high risk of recurrence.

Secondary hematopoietic malignancies in survivors of childhood cancer: an analysis of 111 cases from the Surveillance, Epidemiology, and End Result-9 registry

BACKGROUND

Studying secondary hematological malignancies in a large cohort of patients can help predict risks and trends associated with current therapies.

METHODS

The authors analyzed data from the Surveillance, Epidemiology, and End Resultsecondary 9 (SEER-9) database on patients with a primary malignancy (diagnosed before the age of 20 years) between 1973 and 2005 who developed a secondary hematological malignancy. Primary cancer and histological subtype, incidence, risk factors, outcomes, and changes in risk patterns of secondary hematological malignancies were analyzed for 1973 to 1985, 1986 to 1995, and 1996 to 2005. Standardized incidence ratios (SIRs) of observed to expected cancers were calculated.

RESULTS

Of 34,867 patients with a histology-confirmed primary malignancy, 111 developed secondary hematological malignancies (median, 44 months). Lymphoma was the commonest primary cancer (n = 47). The main histological subtype of secondary hematological malignancy was acute myeloid leukemia (AML) (49%), which had the shortest median latency time and the worst 5-year survival (18% ± 5.3%; P = .044). Secondary Hodgkin lymphoma had the best 5-year survival (83% ± 15%). The 5-year overall survival for patients with secondary hematological malignancies was 31% ± 4.7%. The risk of secondary AML steadily increased from 1986 to 2005, whereas SIRs for acute lymphoblastic leukemia did not change over time. Non-Hodgkin lymphoma, the second most common secondary hematological malignancy, occurred at a median of 112 months, and its risk steadily increased over time periods.

CONCLUSIONS

Childhood cancer survivors are at increased risk of developing secondary hematological malignancies, particularly secondary AML. This risk has continued to rise even in recent years, emphasizing the need to study other factors contributing to secondary hematological malignancies and closely monitor these patients.

Treatment of adult rhabdomyosarcoma

OBJECTIVES

Rhabdomyosarcoma is an exceedingly rare tumor in adults, and standard chemotherapy used for children is much less effective in adults. This study examines short-term outcomes using doxorubicin, ifosfamide, and vincristine for adult rhabdomyosarcoma.

METHODS

Pathology records were searched for adults (age, >18) with rhabdomyosarcoma treated at our musculoskeletal tumor center. Treatment involved surgical resection, radiation therapy, and chemotherapy with doxorubicin, ifosfamide, and vincristine. Eleven met inclusion criteria. Mean age was 49 (range: 19-72). Tumors sites included upper extremity (4 patients), lower extremity (6), and cervix (1). Subtypes were pleomorphic (7), alveolar (1), embryonal (1), and mixed alveolar/embryonal (2).

RESULTS

Of the 7 patients with nonmetastatic disease, 6 had no evidence of disease posttreatment, but 1 died of myelodysplastic syndrome after 51 months. Three patients who received neoadjuvant chemotherapy had 100% tumor necrosis. One patient with positive margins scheduled for adjuvant chemotherapy had local recurrence and metastasis within 2 weeks and died 5 months later. Of the 4 patients with metastatic disease on presentation, 1 had complete response, 2 had partial response with later progression and death at 8 and 24 months, and 1 had immediate progression and died at 12 months. Mean overall survival was 24 months with 6 of 11 (55%) alive at last follow-up. Mean disease-free survival was 17 months for all patients and 23 months for the 7 patients who had remission of all disease.

CONCLUSIONS

When combined with surgery and radiation therapy, chemotherapy using doxorubicin, ifosfamide, and vincristine yielded 55% overall and 64% disease-free survival at 2 years.

Reduced risk of secondary leukemia with fewer cycles of dose-intensive induction chemotherapy in patients with neuroblastoma

BACKGROUND

We report a prospective study of secondary leukemia (SL)/myelodysplastic syndrome (MDS) in neuroblastoma (NB) patients treated with > or =5 cycles of dose-intensive chemotherapy.

PROCEDURE

NB patients received induction with high-dose cyclophosphamide (4,200 mg/m(2))-doxorubicin (75 mg/m(2))-vincristine (cycles 1, 2, 4, 6, 8), and high-dose cisplatin (200 mg/m(2))-etoposide (600 mg/m(2)) (cycles 3, 5, 7). Bone marrow was examined every 1-3 months for > or =36 months, with inclusion of extensive chromosomal studies 1-3 months post-induction and 1-2x/year thereafter.

RESULTS

One hundred eight four patients received 5 (n = 76), 6 (n = 45), 7 (n = 59), or 8 (n = 4) cycles. Eight patients developed SL/MDS (only one each in the 5- and 6-cycle groups), at 12-50 months, including two cases detected in surveillance studies. Among 108 patients who received > or =6 cycles, the 5-year cumulative incidence was 7.1% (95% CI: 2%, 12.2%), versus 0% among 54 patients who received 5 cycles without maintenance oral etoposide. Five-year cumulative incidences were 1.46%, 2.28%, and 8.47% among patients in the 5-, 6-, and 7-cycle groups, with fewer cycles having a significantly lower risk (P = 0.048). There was no significant association of risk with potentially leukemogenic consolidative treatments (targeted radiotherapy, myeloablative therapy, and oral etoposide).

CONCLUSIONS

Reducing the number of dose-intensive cycles significantly decreases the risk of SL/MDS, yielding 5-year rates matching the low range (0.4-2.2%) reported for moderate-dose combination chemotherapy regimens used against other pediatric solid tumors.

Evaluation of chromosome 5 aberrations in complex karyotypes of patients with myeloid disorders reveals their contribution to dicentric and tricentric chromosomes, resulting in the loss of critical 5q regions

Dicentric chromosomes have often been observed in complex karyotypes in previously reported studies of therapy-related myelodysplastic syndromes (MDS) and acute myeloid leukemia (AML). Fluorescence in situ hybridization (FISH) has now made the characterization of these rearrangements much easier. Dicentric and tricentric chromosomes were identified in 21 patients (9 MDS and 12 AML) among the 133 consecutive MDS/AML patients (17%) who had a structural or numerical aberration of chromosome 5 using conventional cytogenetic analysis. One third (7/21) of the patients had received alkylating drugs for a previously diagnosed cancer or chronic myeloproliferative disease. Loss of 5q material was identified in all 21 patients. One copy of the EGR1 (5q31) or the CSF1R (5q33 approximately q34) genes was lost in 20 of the 21 patients. Dicentric and tricentric chromosomes involving chromosome 5 are frequently observed in complex karyotypes among patients with de novo or therapy-related MDS/AML. They lead to deletions of various parts of the long arm of chromosome 5.

New malignancies following childhood cancer in the United States, 1973–2002

The objectives of our study were to quantify risks for developing new malignancies among childhood cancer survivors, identify links between particular types of first and subsequent cancer, and evaluate the possible role of treatment. A cohort of 25,965 2-month survivors of childhood cancer diagnosed in the U.S. during 1973-2002 was identified and followed through SEER cancer registries. Observed-to-expected ratios (O/E) were calculated, and Poisson regression was used to compare risks among treatment groups. Childhood cancer survivors were at nearly 6-fold risk of developing a new cancer relative to the general population (O/E = 5.9, 95% CI: 5.4-6.5). Most common were subsequent primary cancers of the female breast, central nervous system, bone, thyroid gland and soft tissue, as well as cutaneous melanoma and acute non-lymphocytic leukemia (ANLL). The greatest risks of subsequent cancers occurred among patients diagnosed previously with Hodgkin lymphoma (HL), Ewing sarcoma, primitive neuroectodermal tumor, or retinoblastoma. Risk of subsequent solid cancers was higher among persons whose initial treatment for childhood cancer included radiotherapy, whereas the excess of subsequent ANLL was strongly related to chemotherapy. The O/E for subsequent ANLL increased with increasing calendar year of initial cancer diagnosis among survivors of cancers other than HL, most likely due to increasing use of leukemogenic drugs for solid cancers and non-Hodgkin lymphoma. Childhood cancer survivors are at markedly increased risk of developing a variety of new cancers relative to the general population, but the magnitude of excess risk and specific types of second cancer vary widely by type of first cancer.

Topoisomerase II and the etiology of chromosomal translocations

Acute leukemias with balanced chromosomal translocations, protean morphologic and immunophenotypic presentations but generally shorter latency and absence of myelodysplasia are recognized as a complication of anti-cancer drugs that behave as topoisomerase II poisons. Translocations affecting the breakpoint cluster region of the MLL gene at chromosome band 11q23 are the most common molecular genetic aberrations in leukemias associated with the topoisomerase II poisons. These agents perturb the cleavage-religation equilibrium of topoisomerase II and increase cleavage complexes. One model suggests that this damages the DNA directly and leads to chromosomal breakage, which may result in untoward DNA recombination in the form of translocations. This review will summarize the evidence for topoisomerase II involvement in the genesis of translocations and extension of the model to acute leukemia in infants characterized by similar MLL translocations.

Etoposide and illegitimate DNA double-strand break repair in the generation of MLL translocations: new insights and new questions

Faithful repair of chromosomal double-strand breaks (DSBs) is central to genome integrity and the suppression of genome rearrangements including translocations that are a hallmark of leukemia, lymphoma, and soft-tissue sarcomas [B. Elliott, M. Jasin, Double-strand breaks and translocations in cancer, Cell. Mol. Life Sci. 59 (2002) 373-385; D.C. van Gent, J.H. Hoeijmakers, R. Kanaar, Chromosomal stability and the DNA double-stranded break connection, Nat. Rev. Genet. 2 (2001) 196-206]. Chemotherapy agents that target the essential cellular enzyme topoisomerase II (topo II) are known promoters of DSBs and are associated with therapy-related leukemias. There is a clear clinical association between previous exposure to etoposide and therapy-related acute myeloid leukemia (t-AML) characterized by chromosomal rearrangements involving the mixed lineage leukemia (MLL) gene on chromosome band 11q23 [C.A. Felix, Leukemias related to treatment with DNA topoisomerase II inhibitors, Med. Pediatr. Oncol. 36 (2001) 525-535]. Most MLL rearrangements initiate within a well-characterized 8.3 kb region that contains both putative topo II cleavage recognition sequences and repetitive elements leading to the logical hypothesis that MLL is particularly susceptible to aberrant cleavage and homology-mediated fusion to repetitive elements located on novel chromosome partners. In this review, we will discuss the findings and implications of recent attempts to confirm this hypothesis.

Second malignancy in 597 patients with ewing sarcoma of bone treated at a single institution with adjuvant and neoadjuvant chemotherapy between 1972 and 1999

The relative risk of second tumors in patients with Ewing sarcoma is controversial, and little is known about their treatment and outcome. The purpose of the current study was to define the incidence and features of second tumors among 597 long-term survivors of nonmetastatic Ewing sarcoma treated with adjuvant and neoadjuvant chemotherapy, radiotherapy, and/or surgery. The authors found that the risk of secondary malignancy after adjuvant or neoadjuvant treatment of Ewing sarcoma is higher than that after other childhood or adolescent cancers only after radiotherapy. Based on this, postoperative radiotherapy should be avoided when surgery with adequate margins is feasible.

Widespread intratumoral virus distribution with fractionated injection enables local control of large human rhabdomyosarcoma xenografts by oncolytic herpes simplex viruses

Novel methods of local control for sarcomas are needed. We investigated the antitumor effect of two related herpes simplex virus (HSV) mutants, NV1020 and NV1066, on human rhabdomyosracoma cells and xenografts. Cell death correlated with virus replication and apoptosis in cultured cells and tumors. Complete regression was seen in all tumors <250 mm(3) following a single injection, yet only half of tumors >250 mm(3) showed a complete response. Fractionation of the virus dose into five injection sites did not increase transduction efficiency, transgene expression, or virus production, but did yield more widespread intratumoral distribution. Despite the same total dose of virus, improved control of large tumors was seen using fractionated injections as all large tumors (500-700 mm(3)) had durable, complete regression. Our data suggest that oncolytic HSVs may be useful for local control of bulky rhabdomyosarcoma tumors and that fractionated virus administration results in a more widespread virus infection and better tumor control. Therefore, strategies to maximize intratumoral virus distribution at initial delivery should be sought.

The risk of developing second cancers among survivors of childhood soft tissue sarcoma

BACKGROUND

Previous studies have shown that children who are treated for soft tissue sarcoma (STS) are at increased risk for developing second cancers. However, the risk for specific cancer sites and variations in risk by treatment and STS histology remain unclear.

METHODS

The study evaluated 1499 children (age < 18 years) who survived for > or = 1 year after they were diagnosed with STS and who were reported to the Surveillance, Epidemiology, and End Results (SEER) population-based cancer registries from 1973 to 2000.

RESULTS

Twenty-seven children developed 28 subsequent primary malignancies, compared with 4.5 expected malignancies based on general population rates (observed-to-expected [O/E] ratio = 6.3 (95% confidence interval [95% CI], 4.2-9.1). The risk of developing a subsequent malignancy was increased among children with rhabdomyosarcoma (observed = 11 malignancies; O/E ratio = 7.7), fibromatous neoplasms (observed = 9 malignancies; O/E ratio = 5.8), and other specified STS (observed = 7 malignancies; O/E ratio = 6.5). Initial therapy with radiation and chemotherapeutic agents was associated with a significantly higher risk of second malignancies compared with surgery alone (O/E ratio = 15.2 vs. 1.4; P < 0.0001). Elevated risks were observed for acute myeloid leukemia, cutaneous melanoma, female breast cancer, and sarcomas of the bone and soft tissue, with generally higher risks among patients who initially received combined modality therapy. Excess cancers of the oral cavity were prominent among long-term survivors. For several children, the pattern of multiple malignancies was consistent with a genetic syndrome, particularly neurofibromatosis type 1 and Li-Fraumeni syndrome.

CONCLUSIONS

The risk of second malignancies was increased for all histologic types of childhood STS and was particularly high among patients who received combined modality therapy.

Late events occurring five years or more after successful therapy for childhood rhabdomyosarcoma: a report from the Soft Tissue Sarcoma Committee of the Children's Oncology Group

The aim of our study was to describe late failures in children who initially survived event-free five years from a diagnosis of rhabdomyosarcoma. Charts of children enrolled in the Intergroup Rhabdomyosarcoma Study Group (IRSG) trials III, IV pilot and IV (1984-1997) who survived five years event-free and subsequently experienced an adverse event (disease recurrence, second malignant neoplasm or death from other causes) were reviewed. Of the 2534 enrolled patients, 1160 were event-free at five years and 48 subsequently experienced a late event. The estimated 10-year event rate for the 1160 patients who were alive and event-free at five years was 9% (95% Confidence Interval (CI) 5%, 13%). Patients with both advanced disease (Group III/IV) and large primary tumours at diagnosis (> 5 cm) were at the highest risk for late events (19%; 95% CI 8%, 30%). Late events after successful treatment for rhabdomyosarcoma occur in 9%. Those with advanced disease and large primary tumours have the highest risk of late events.

Granulocyte colony-stimulating factor and the risk of secondary myeloid malignancy after etoposide treatment

Event-free survival for children with acute lymphoblastic leukemia (ALL) now exceeds 80% in the most effective trials. Failures are due to relapse, toxicity, and second cancers such as therapy-related myeloid leukemia or myelodysplasia (t-ML). Topoisomerase II inhibitors and alkylators can induce t-ML; additional risk factors for t-ML remain poorly defined. The occurrence of t-ML among children who had received granulocyte colony-stimulating factor (G-CSF) following ALL remission induction therapy prompted us to examine this and other putative risk factors for t-ML in 412 children treated on 2 consecutive ALL protocols from 1991 to 1998. All children received etoposide and anthracyclines, 99 of whom received G-CSF; 284 also received cyclophosphamide, 58 of whom also received cranial irradiation. There were 20 children who developed t-ML at a median of 2.3 years (range, 1.0-6.0 years), including 16 cases of acute myeloid leukemia, 3 myelodysplasia, and 1 chronic myeloid leukemia. Stratifying by protocol, the cumulative incidence functions differed (P =.017) according to the use of G-CSF and irradiation: 6-year cumulative incidence (standard error) of t-ML of 12.3% (5.3%) among the 44 children who received irradiation without G-CSF, 11.0% (3.5%) among the 85 children who received G-CSF but no irradiation, 7.1% (7.2%) among the 14 children who received irradiation plus G-CSF, and 2.7% (1.3%) among the 269 children who received neither irradiation nor G-CSF. Even when children receiving irradiation were excluded, the incidence was still higher in those receiving G-CSF (P =.019). In the setting of intensive antileukemic therapy, short-term use of G-CSF may increase the risk of t-ML.

Second malignancies after ewing tumor treatment in 690 patients from a cooperative German/Austrian/Dutch study

BACKGROUND

Ewing tumor treatment involves high cumulative doses of alkylating agents and topoisomerase inhibitors, drugs capable of inducing second cancers. We analyzed the second cancer risk in a large cohort of consistently treated patients.

PATIENTS AND METHODS

Six hundred ninety Ewing tumor patients were treated between 1992 and 1999 with local therapy and vincristine. doxorubicin, ifosfamide and/or cyclophosphamide, and antinomycin D, with or without etoposide as a randomized question. Second cancer incidences were estimated by competing risk analyses; standardized incidence ratios (SIR) in comparison to registry data were compiled.

RESULTS

After a median observation time of 56 months (32 months for survivors), 6 of 690 patients had developed second cancers: MDS/AML, two, ALL/NHL, two, squamous cell carcinoma, one, liposarcoma, one. SIR were increased 20-30 fold in comparison to the general population. The cumulative second cancer risk five years after diagnosis of the Ewing tumor was 0.0093 for the total group, zero for patients without etoposide, and 0.0118 with etoposide. Additional phase II high-dose therapy increased the risk to 0.0398 after five years.

CONCLUSIONS

The second cancder risk observed was in the range to be expected in cancer survivors. High-dose therapy, and less markedly, etoposide, may contribute to the overall second cancer risk.

Development of acute myeloid leukemia after chemotherapy for osteosarcoma

The current study describes two patients with osteosarcoma who had acute myeloid leukemia develop after treatment with multiagent chemotherapy. The incidence density for the chemotherapy protocol was 129.8 per 10,000 person-year of followup. Karyotype analysis of 16 reported patients (including the current two patients) indicated that most leukemias after treatment of osteosarcoma correlated with the use of topoisomerase II inhibitors, such as doxorubicin. The deoxyribonucleic acid-damaging activity of doxorubicin reinforced by the use of alkylating agents is highly suspected as a causative event in the development of leukemia after treatment of osteosarcoma. As the next step in the development of treatment for patients with osteosarcoma, the type and intensity of treatment must be evaluated to minimize possible leukemogenic effects without compromising the potential for cure.

Intergroup rhabdomyosarcoma study-IV: results for patients with nonmetastatic disease

PURPOSE

The study goal was to improve outcome in children with rhabdomyosarcoma by comparing risk-based regimens of surgery, radiotherapy (RT) and chemotherapy.

PATIENTS AND METHODS

Eight hundred eighty-three previously untreated eligible patients with nonmetastatic rhabdomyosarcoma entered the Intergroup Rhabdomyosarcoma Study-IV (IRS-IV) (1991 to 1997) after surgery and were randomized treatment by primary tumor site, group (1 to 3), and stage (I to III). Failure-free survival (FFS) rates and survival were the end points used in comparisons between randomized groups and between patient subgroups treated on IRS-III and IRS-IV. Most patients were randomized to receive vincristine and dactinomycin (VA) and cyclophosphamide (VAC, n = 235), or VA and ifosfamide (VAI, n = 222), or vincristine, ifosfamide, and etoposide (VIE, n = 236). Patients with group 3 tumors were randomized to receive conventional RT (C-RT) versus hyperfractionated RT (HF-RT).

RESULTS

Overall 3-year FFS and survival were 77% and 86%, respectively. Three-year FFS rates with VAC, VAI, and VIE were 75%, 77%, and 77%, respectively (P =.42). No significant difference in outcome was noted with HF-RT versus C-RT (P =.85 and P =.90, respectively). Overall, patients with embryonal tumors benefited from intensive three-drug chemotherapy in IRS-IV (3-year FFS, 83%). The improvement was seen for patients with stage I or stage II/III, group 1/2 disease, many of whom received VA chemotherapy on IRS-III. Patients with stage 2/3, group 3 disease had similar outcomes on IRS-III and IRS-IV. Three-year FFS for the nonrandomized patient subsets was 75% with renal abnormalities; 81% for paratesticular, group 1 cases; and 91% for group 1/2 orbit or eyelid tumors. Patients with paratesticular primaries had poorer outcomes if they were more than 10 years old (3-year FFS, 63% v 90%). Myelosuppression occurred in most patients, but toxic deaths occurred in less than 1%.

CONCLUSION

VAC and VAI or VIE with surgery (with or without RT), are equally effective for patients with local or regional rhabdomyosarcoma and are more effective for embryonal tumors than therapies used previously. Younger patients with group 1 paratesticular embryonal tumors and all patients with group 1/2 orbit or eyelid tumors can usually be cured with VA chemotherapy along with postoperative RT for group 2 disease.

Therapy-related leukemia associated with alkylating agents

The leukemogenic potential of alkylating agents has been known for many years and almost all alkylating agents in clinical use have been shown to increase the risk of leukemia. With these drugs the risk of leukemia appears to increase with increasing patient age, as does the risk of de novo myeloid leukemia in the population. Susceptibility to alkylating agent-associated leukemia is influenced by the genetic constitution of the patient, and by the nature of the exposure. To illustrate the importance of these factors in etiology of leukemia, this paper discusses the contribution of disorders such as Fanconi anemia and neurofibromatosis to susceptibility to alkylating agent-associated leukemia. This paper also discusses the contribution of alkylating agents and other therapeutic exposures in the etiology of leukemias occurring after autologous bone marrow transplant.

Leukemias related to treatment with DNA topoisomerase II inhibitors

The epipodophyllotoxins etoposide and teniposide and other DNA topoisomerase II inhibitors including anthracyclines and dactinomycin are highly efficacious anticancer drugs. All are associated with a distinct form of leukemia characterized by chromosomal translocations as a treatment complication. Most of the translocations disrupt a breakpoint cluster region (bcr) of the MLL gene at chromosome band 11q23. Other characteristic translocations also may occur. The normal function of the nuclear enzyme DNA topoisomerase II is to catalyze changes in DNA topology between relaxed and supercoiled states by transiently cleaving and re-ligating both strands of the double helix. Anticancer drugs that are DNA topoisomerase II inhibitors are cytotoxic because they form complexes with DNA and DNA topoisomerase II. The complexes decrease the re-ligation rate, disrupt the cleavage-re-ligation equilibrium, and have a net effect of increasing cleavage. The increased cleavage damages the DNA and leads to chromosomal breakage. Cells with irreparable DNA damage die by apoptosis. The association of DNA topoisomerase II inhibitors with leukemia suggests that the drug-induced, DNA topoisomerase II-mediated chromosomal breakage may be relevant to translocations in addition to this anti-neoplastic, cytotoxic action. Epidemiological studies, genomic translocation breakpoint cloning and in vitro DNA topoisomerase II cleavage assays together lead to a model for treatment-related leukemia in which DNA topoisomerase II causes chromosomal breakage and translocations form when the breakage is repaired.

Progress in the diagnosis and treatment of rhabdomyosarcoma and related soft tissue sarcomas

Advances in the diagnosis and treatment of rhabdomyosarcoma and related soft tissue sarcomas continue in the Intergroup Rhabdomyosarcoma Study Group (IRSG) and European cooperative groups. The use of molecular biology techniques in soft tissue sarcomas are redefining the classic pathology of these small blue cell tumors. Improvements in imaging, radiotherapy, and surgery, in part, deserve credit for the better survival seen in all cooperative trials. These advances confound the interpretation of consecutively run chemotherapy trials using historical comparisons. The IRSG has reported improvement in the prognosis of both nonmetastatic and metastatic embryonal rhabdomyosarcoma as attributable to three, three-drug regimens that use cyclophosphamide at 2.2 g/m2 in either maintenance or induction and maintenance therapy. Patients of any age with metastatic, nonembryonal, and those over 10 years of age with metastatic embryonal rhabdomyosarcoma continue to have a poor prognosis, which even megatherapy has failed to change. The doublet of ifosfamide and etoposide in combination with vincristine, actinomycin D, and cyclophosphamide at 2.2 g/m2 achieved a remarkable 3-year survival of 58% in patients with metastatic rhabdomyosarcoma and undifferentiated soft tissue sarcoma. The topoisomerase I inhibitor, topotecan, has recently been found by the IRSG to have a 57% overall response rate in patients with metastatic alveolar rhabdomyosarcoma. Topotecan has completed testing with cyclophosphamide in a phase II window study in newly diagnosed patients with metastatic disease and has been incorporated into a randomized trial in intermediate risk patients in IRSG-V. Molecular studies in IRSG-V will be applied in the detection of occult bone marrow metastases and the evaluation of resection margins at initial and second-look surgery. Long-term follow-up will be required in patients with gross residual sarcoma randomized to conventional and hyperfractionated radiotherapy in IRSG-IV to assess late effects. Although older patients with unfavorable histology and metastatic disease continue to have a poor prognosis, the overall 5-year survival of children and adolescents with nonmetastatic and metastatic rhabdomyosarcoma is approaching 80%. As molecular discoveries advance the diagnosis and detection of rhabdomyosarcoma, it is hoped that the futuristic molecular based treatment strategies in development and early testing will further improve survival in high-risk patients with metastatic soft tissue sarcoma.

Secondary myelodysplasia with monosomy 7 arising after treatment for acute lymphoblastic leukemia in childhood

Monosomy 7 is recognized as a characteristic, clonal abnormality associated with acquired myelodysplasia (MDS) or acute myeloid leukemia (AML). It can occur as a late complication of cytotoxic therapy and is usually associated with exposure to alkylating agents or radiation therapy. We report two patients with therapy-related myelodysplasia (t-MDS) associated with monosomy 7 occurring in children after completion of therapy for acute lymphoblastic leukemia (ALL). Both children were noted to have t-MDS with monosomy 7 at the time of cessation of chemotherapy. Neither child had received an alkylating agent or radiation therapy during treatment. One child had a unique dicentric marker chromosome that was shown by fluorescent in situ hybridization to be derived from chromosome 7. This report emphasizes the need to identify and minimize therapy-related side effects without compromising cure rates.

Treatment-related leukaemia--a clinical and scientific challenge

The development of a second tumour, including treatment-related leukaemia (TRL), is the most devastating complication of intensive cancer chemotherapy. This is especially relevant in the paediatric population as over 70% of children diagnosed with a malignancy will now live at least 5 years. Most TRLs are myeloid leukaemias and carry an overall poor prognosis when compared with their de novo counterparts. Despite the well known association with specific cytotoxic agents, improved understanding of the pathogenesis and risk factors of TRL is ultimately essential if we are to develop successful strategies for prevention and treatment. Here we review these aspects, together with the clinical and diverse biological features of this complication and the efficacy of current therapy.

The long-term complications of chemotherapy in childhood genitourinary tumors

Combination chemotherapy, often in conjunction with surgery and external radiotherapy, is utilized in most children with tumors of the genitourinary tract. These chemotherapeutic agents are capable of causing a variety of delayed toxicities. Common late complications include cardiotoxicity associated with prior exposure to an anthracycline, pulmonary dysfunction, infertility in males due to prior therapy with alkylating agents, and secondary leukemia in individuals treated with epipodophyllotoxins.

Hematologic abnormalities and acute myeloid leukemia in children and adolescents administered intensified chemotherapy for the Ewing sarcoma family of tumors

PURPOSE

Current treatment of the Ewing sarcoma family of tumors (ESFT) includes intensive multiagent chemotherapy with topoisomerase II inhibitors, alkylating agents, and granulocyte colony-stimulating factor (G-CSF). This treatment approach has been associated with myelodysplasia and acute myeloid leukemia. Because macrocytosis and thrombocytopenia are distinctive features of myelodysplasia, the authors evaluated a cohort of patients treated for ESFT to determine the degree and duration of macrocytosis and thrombocytopenia and their relation with the development of therapy-related hematologic malignancies.

PATIENTS AND METHODS

The study group consisted of 73 patients with ESFT treated on two consecutive protocols (EW92 and EW87). Both chemotherapy regimens incorporated the same agents but differed in cumulative drug dose, dose per course, and the use of G-CSF. Platelet counts and the mean corpuscular volume (MCV) of erythrocytes were determined at diagnosis and during follow-up visits after completion of treatment.

RESULTS

Patients in the EW92 group had significantly greater MCVs after treatment than did the less intensively treated EW87 group. These changes persisted throughout the 40-month observation period. Patients in the EW92 group also had lesser mean platelet counts after treatment than those in the EW87 group. MCV differences (from baseline) were inversely related to platelet counts. The cumulative incidence of treatment-related acute myeloid leukemia was 7.8%+/-4.7% at 4 years in the EW92 group and zero in the EW87 group.

CONCLUSION

Patients treated for ESFT with intensive chemotherapy that includes large doses of alkylators, topoisomerase II inhibitors, and G-CSF characteristically have persistently elevated MCVs and decreased platelet counts after completion of therapy. These hematologic abnormalities may represent stem cell damage, predisposing patients to myelodysplasia and acute myeloid leukemia, but further study is needed to establish this relation.

Late complications of therapy in 213 children with localized, nonorbital soft-tissue sarcoma of the head and neck: A descriptive report from the Intergroup Rhabdomyosarcoma Studies (IRS)-II and - III. IRS Group of the Children's Cancer Group and the Pediatric Oncology Group

BACKGROUND

This review of children and adolescents with nonorbital soft-tissue sarcoma of the head and neck was undertaken to describe late sequelae of treatment, as manifested primarily by problems with statural growth, facial and nuchal symmetry, dentition, vision and hearing, and school performance.

PROCEDURE

Four hundred sixty-nine patients entered the IRS-II and -III protocols with localized, nonorbital soft-tissue sarcomas of the head and neck from 1978 through 1987. Their overall survival rate was 53% (250/469) at 5 years. Two hundred thirteen patients were surviving relapse-free 5 or more years after diagnosis, for whom there were serial height measurements at 2 or more years after initiation of therapy. Their median age at diagnosis was 5 years; the median length of follow-up was 7 years. All received multiple-agent chemotherapy, and all but 3 received irradiation to the primary tumor volume. Sixty-eight percent of the tumors arose in cranial parameningeal sites, 22% in nonparameningeal sites, and 10% in the neck. We reviewed flow sheets submitted to the IRS Group Statistical Office to ascertain which late sequelae were recorded.

RESULTS

One hundred sixty-four patients (77%) had one or more problems recorded. One hundred ninety of the two hundred thirteen patients (89%) were under 15 years of age at study entry, and at follow-up 92 (48%) had failed to maintain their initial height velocity, which had decreased by more than 25 percentile points from the original value. Thirty-six of the one hundred ninety patients (19%) were receiving growth hormone injections. Hypoplasia or asymmetry of tissues in the primary tumor site was reported in 74 patients, and 13 underwent reconstructive surgery. Poor dentition or malformed teeth were noted in 61 patients. Impaired vision developed in 37 patients, owing primarily to cataracts, corneal changes, and optic atrophy. Thirty-six patients had decreased hearing acuity, and 9 were fitted with hearing aids; 5 of these 9 had received cisplatin. Thirty-five patients were noted to have problems learning in school. Four patients developed a second malignancy (two sarcomas, one carcinoma, one leukemia).

CONCLUSIONS

Late sequelae affected the majority of these patients treated for soft-tissue sarcoma of the head and neck on IRS-II and -III. The potential impact of certain sequelae could be reduced by specific measures, such as surgical reconstruction and hormonal therapy. Late sequelae must be taken into account in designing future curative treatments.

A critical risk-benefit assessment argues against the use of anthracyclines in induction regimens for newly diagnosed childhood acute lymphoblastic leukemia

Although anthracyclines are associated with significant cardiac toxicity and their benefit remains unclear, they are included in nearly all current protocols for the treatment of childhood acute lymphoblastic leukemia (ALL). Currently open trials from most major groups use anthracyclines in the induction phase for all high-risk patients and in the delayed intensification phase for all patients regardless of risk classification. Our review of published randomized studies reveals no benefit for the addition of anthracyclines to induction phase of childhood ALL regimens consisting of vincristine, prednisone, and L-asparaginase (VPL), with or without a delayed intensification phase. No randomized studies have evaluated the use of anthracyclines in the delayed intensification phase of therapy. Furthermore, studies of relapsed patients indicated no benefit for the addition anthracyclines to maintenance regimens. Recent evidence from preclinical studies suggests that a combination of VPL with an anti-CD19 immunotoxin is more effective than VPL plus anthracyclines combination. Accumulated evidence exists that anthracyclines are associated with late-onset cardiac morbidity in about 25% of childhood ALL and other cancer survivors, and about 5% develop overt heart failure, with some requiring cardiac transplantation. Anthracycline-induced cardiotoxicity in children has no safe dose threshold and all doses are likely to cause significant myocardial damage. New data suggests that a unique cardiac mitochondrial exogenous NADH dehydrogenase is responsible for the anthracycline-induced oxygen radicals damage to the heart, and that chelators currently evaluated may not prevent late-onset cardiotoxicity in children. In view of these findings we urge extreme caution in using anthracyclines as part of multimodality ALL treatment programs, and strongly recommend reevaluation of what should be considered the best induction regimen for high-risk childhood ALL.

Soft tissue sarcomas in children

In childhood, soft tissue sarcomas comprise a complex group of malignancies of varied histologic subtypes, the prognoses of which depend on the histology, age, site, extent of involvement and a variety of other factors. This paper discusses the varieties of tumors classified as soft tissue sarcomas in childhood and the multimodal approach taken to cure these tumors, with particular attention to the details of difficult surgical problems.

Secondary leukemia or myelodysplastic syndrome after treatment with epipodophyllotoxins

PURPOSE

The incidence of secondary leukemia after epipodophyllotoxin treatment and the relationship between epipodophyllotoxin cumulative dose and risk are not well characterized. The Cancer Therapy Evaluation Program (CTEP) of the National Cancer Institute (NCI) has developed a monitoring plan to obtain reliable estimates of the risk of secondary leukemia after epipodophyllotoxin treatment.

METHODS

Twelve NCI-supported cooperative group clinical trials were identified that use epipodophyllotoxins at low (<1.5 g/m2 etoposide), moderate (1.5 to 2.99 g/m2 etoposide), or higher (> or =3.0 g/m2 etoposide) cumulative doses. Cases of secondary leukemia (including treatment-related myelodysplastic syndrome) occurring on these trials have been reported to CTEP, as has duration of follow-up for all patients, thereby allowing calculation of cumulative 6-year incidence rates of secondary leukemia for each etoposide dose group.

RESULTS

The calculated cumulative 6-year risks for development of secondary leukemia for the low, moderate, and higher cumulative dose groups were 3.3%, (95% upper confidence bound of 5.9%), 0.7% (95% upper confidence bound of 1.6%), and 2.2%, (95% upper confidence bound of 4.6%), respectively.

CONCLUSION

Within the context of the epipodophyllotoxin cumulative dose range and schedules of administration encompassed by the monitoring plan regimens, and within the context of multiagent chemotherapy regimens that include alkylating agents, doxorubicin, and other agents, factors other than epipodophyllotoxin cumulative dose seem to be of primary importance in determining the risk of secondary leukemia. Data obtained by the CTEP secondary leukemia monitoring plan support the relative safety of using epipodophyllotoxins according to the therapeutic plans outlined in the monitored protocols.

Secondary leukemias induced by topoisomerase-targeted drugs

The major established cause of acute myeloid leukemia (AML) in the young is cancer chemotherapy. There are two forms of treatment-related AML (t-AML). Each form has a de novo counterpart. Alkylating agents cause t-AML characterized by antecedent myelodysplasia, a mean latency period of 5-7 years and complete or partial deletion of chromosome 5 or 7. The risk is related to cumulative alkylating agent dose. Germline NF-1 and p53 gene mutations and the GSTT1 null genotype may increase the risk. Epipodophyllotoxins and other DNA topoisomerase II inhibitors cause leukemias with translocations of the MLL gene at chromosome band 11q23 or, less often, t(8;21), t(3;21), inv(16), t(8;16), t(15;17) or t(9;22). The mean latency period is about 2 years. While most cases are of French-American-British (FAB) M4 or FAB M5 morphology, other FAB AML subtypes, myelodysplastic syndrome (MDS), acute lymphoblastic leukemia (ALL) and chronic myelogenous leukemia (CML) occur. Between 2 and 12% of patients who receive epipodophyllotoxin have developed t-AML. There is no relationship with higher cumulative epipodophyllotoxin dose and genetic predisposition has not been identified, but weekly or twice-weekly schedules and preceding l-asparaginase administration may potentiate the risk. The translocation breakpoints in MLL are heterogeneously distributed within a breakpoint cluster region (bcr) and the MLL gene translocations involve one of many partner genes. DNA topoisomerase II cleavage assays demonstrate a correspondence between DNA topoisomerase II cleavage sites and the translocation breakpoints. DNA topoisomerase II catalyzes transient double-stranded DNA cleavage and rejoining. Epipodophyllotoxins form a complex with the DNA and DNA topoisomerase II, decrease DNA rejoining and cause chromosomal breakage. Furthermore, epipodophyllotoxin metabolism generates reactive oxygen species and hydroxyl radicals that could create abasic sites, potent position-specific enhancers of DNA topoisomerase II cleavage. One proposed mechanism for the translocations entails chromosomal breakage by DNA topoisomerase II and recombination of DNA free ends from different chromosomes through DNA repair. With few exceptions, treatment-related leukemias respond less well to either chemotherapy or bone marrow transplantation than their de novo counterparts, necessitating more innovative treatments, a better mechanistic understanding of the pathogenesis, and strategies for prevention.

The heterogeneity of leukemia occurring after treatment for sarcoma

The successful treatment of sarcomas with intensive regimens combining high-dose chemotherapy and irradiation has led to not only improved survival but also to an increased incidence of therapy-related acute non-lymphocytic leukemia (t-ANLL) and myelodysplastic syndrome (MDS). We report 4 patients having sarcoma treated with chemotherapy or chemoradiotherapy who subsequently developed MDS or t-ANLL.

Rhabdomyosarcoma. Biology and treatment

Rhabdomyosarcoma is the most common soft-tissue sarcoma of childhood. Recognition of specific genetic changes in the two most common subtypes of rhabdomyosarcoma has allowed better understanding of the pathogenesis of this disease. In addition, identification of prognostic factors and the use of risk-directed multimodal therapy have improved the outcome for these patients significantly, with cure rates approaching 70%.

Therapy-related acute myeloid leukemia with t(8;21) in a child with previous Ewing's sarcoma

Cases of secondary acute myeloid leukemia (AML) occurring after treatment for an Ewing's sarcoma are uncommon. Therapy-related AML with t(8;21) translocation is an entity which has been well characterized. A case of AML-2 with t(8;21) and t(3;15) occurring 4 years after treatment for an Ewing's sarcoma with cyclophosphamide, doxorubicin, vincristine, dactinomycin, and radiotherapy, is reported. Autologous bone marrow transplantation was performed during second remission, 23 months after diagnosis. Reverse transcriptase polymerase chain reaction of the AML1/ETO fusion gene product was performed in order to monitor the quality of the remission. The patient currently remains in remission 24 months after the bone marrow transplantation.

Long-term survivors of childhood cancer. The medical consequences of cure

The late effects of cancer therapy are a significant problem and the risk can be predicted based on each individual's prior therapy. Although the use of effective therapy has led to the development of sequelae involving various organ systems, recognition of these complications has led to the design of new therapy targeted at minimizing these effects, especially in patients with good risk. Unfortunately, the risks of the late effects must be accepted in patients with cancers that are aggressive or in advanced stages to maximize the chance for cure. Continued education of cancer survivors regarding their risks of late effects is essential and gives them the ability to maintain healthy lifestyles, avoiding cancer-promoting behaviors such as smoking. It also gives survivors the opportunity to participate in screening programs to help in early recognition of the late consequences of therapy and to learn self-examination to detect second malignancies early. It is hoped that the use of early intervention will lead to an improved long-term outcome. Finally, continued surveillance of this population is essential to monitor the impact of the therapeutic modifications on late complications and potentially to detect the sequelae produced by newer treatment strategies. Because the number of childhood cancer survivors will continue to increase, it is imperative that the pediatricians and internists in the community who care for these survivors are aware of their risks for late effects so that they have access to and can benefit from early intervention.

Ifosfamide and etoposide plus vincristine, doxorubicin, and cyclophosphamide for newly diagnosed Ewing's sarcoma family of tumors

BACKGROUND

This study was conducted to determine the feasibility of, and improve outcome by, incorporating ifosfamide and etoposide (IE) into the therapy of newly diagnosed patients with Ewing's sarcoma family of tumors of bone and soft tissue.

METHODS

Fifty-four newly diagnosed patients received 7 cycles of vincristine, doxorubicin, and cyclophosphamide (VAdriaC) and 11 cycles of IE. Radiation therapy after the fifth chemotherapy cycle was the primary approach to local control.

RESULTS

Actuarial 5-year event-free survival (EFS) and overall survival rates were 42% and 45%, respectively, with a median duration of potential follow-up of 6.8 years. EFS was significantly better for patients with localized tumors than for those with metastatic lesions (64% v. 13%, P < 0.0001). Actuarial local progression-free survival at 5 years was 74%, and did not correlate with primary tumor size or site, histologic subtype, or the presence of metastases. Febrile neutropenia developed after 49% of cycles, and clinical or sub-clinical cardiac dysfunction was common (7% and 40% respectively). There were four toxic deaths and one case of secondary myelodysplastic syndrome.

CONCLUSIONS

Despite substantial toxicity, the integration of IE into the front-line, VAdriaC-based therapy of patients with Ewing's sarcoma family of tumors is feasible and appeared to significantly improve the outcome for patients with high risk localized tumors, but had no impact on the poor prognosis of patients with metastatic tumors. Local control can be achieved in the vast majority of patients using radiotherapy exclusively, even among patients with bulky, central axis tumors. Longer follow-up is needed to evaluate the late effects of this intensive therapy.

Second malignant neoplasms in long-term survivors of childhood rhabdomyosarcoma

BACKGROUND

The occurrence of second malignant neoplasms (SMNs) in successfully treated pediatric patients with cancer has been an area of increasing concern because survival of these patients has improved with intensification of therapy. Therefore, the incidence of SMNs in long term survivors of childhood rhabdomyosarcoma (RMS) was studied.

METHODS

From 1970 to 1989, 210 newly diagnosed patients (median age, 9.7 years; range, 1 month to 27 years) with RMS were treated at Memorial Sloan-Kettering Cancer Center (New York, NY). Multimodality treatment included chemotherapy, surgery, and radiotherapy, when indicated. There were 130 long term survivors (> 2 years off therapy) with a median follow-up of 9 years (range, 2-20 years). The cumulative dose of each chemotherapeutic agent and the radiation doses each patient received were reviewed. Statistical analysis was performed by comparison with the Connecticut Tumor Registry data.

RESULTS

Seven patients developed a SMN, including three with acute nonlymphoblastic leukemia (ANLL) and four with solid tumors. Acute nonlymphoblastic leukemia developed a median of 4.5 years after diagnosis. Of the solid tumors, 3 developed within the radiation field at a median of 10 years after diagnosis, whereas the fourth occurred 9.3 years after initial diagnosis in a patient who did not receive radiotherapy. All seven patients with SMNs received total dactinomycin doses higher than the median (9.6 mg/M2) for the group. All three patients with ANLL received total cyclophosphamide doses higher than the median (16.8 g/M2). Moreover, six of the seven patients received a dose of radiotherapy greater than 4000 cGy. The standardized incidence ratio was: 17.07 (95% confidence interval, 6.68-35.18; P < 0.0001).

CONCLUSIONS

Multimodality therapy has improved long term survival for patients with childhood RMS. The combination of high dose radiotherapy and chemotherapy appears to increase the risk for developing a second malignancy.