William M. Crist

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.

The results of treatment of 686, previously untreated patients younger than 21 years with rhabdomyosarcoma or undifferentiated sarcoma, who were entered on Intergroup Rhabdomyosarcoma Study-I (IRS-I) were analyzed after a minimum potential follow-up time of 7 years. Patients in Clinical Group I (localized disease, completely resected) were randomized to receive either vincristine, dactinomycin, and cyclophosphamide (VAC) or VAC + radiation. At 5 years, approximately 80% of patients given either treatment were still disease-free and there was no significant difference between treatments in the overall percentages of patients surviving of 93% and 81%, respectively (P = 0.67). Patients in Clinical Group II (regional disease, grossly resected) were randomized to receive either vincristine and dactinomycin (VA) + radiation or VAC + radiation. At 5 years, 72% and 65% of the patients, respectively, were disease-free and there was no evidence of a difference between treatments (P = 0.46). The overall survival percentage at 5 years was approximately 72% for both treatments. Patients in Clinical Groups III (gross residual disease after surgery) and IV (metastatic disease) were randomized to receive either "pulse" VAC + radiation or "pulse" VAC + Adriamycin (doxorubicin) + radiation. The complete remission (CR) rate was 69% in Clinical Group III and 50% in IV, with no statistically significant difference in CR rates between treatments in either group. Those who achieved a CR had a nearly 60% chance of staying in remission for 5 years in Clinical Group III compared with approximately 30% in Clinical Group IV. The overall survival percentage at 5 years was 52% in Clinical Group III compared to 20% in Clinical Group IV (P less than 0.0001). The 5-year survival percentage for the entire cohort of 686 patients was 55%. Survival after relapse was poor, being 32% at 1 year and 17% at 2 years. The risk of distant metastasis was much greater than the risk of local recurrence within each clinical group, and there was no evidence of differing types of relapses between treatments. Primary tumors of the orbit and genitourinary tract carried the best prognosis, whereas tumors of the retroperitoneum had the worst prognosis. The authors conclude that for the therapeutic regimens evaluated there was no therapeutic advantage to including radiation in the treatment of Clinical Group I disease, or cyclophosphamide given as a daily low-dose oral regimen in the treatment of Clinical Group II disease or Adriamycin in the treatment of Clinical Groups III and IV diseases.

PURPOSE: Alveolar rhabdomyosarcoma (ARMS) is an aggressive soft tissue malignancy of children and adolescents. Most ARMS patients express PAX3-FKHR or PAX7-FKHR gene fusions resulting from t(2;13) or t(1;13) translocations, respectively. We wished to confirm the diagnostic specificity of gene fusion detection in a large cohort of RMS patients and to evaluate whether these alterations influence clinical outcome in ARMS. PATIENTS AND METHODS: We determined PAX3-FKHR or PAX7-FKHR fusion status in 171 childhood rhabdomyosarcoma (RMS) patients entered onto the Intergroup Rhabdomyosarcoma Study IV, including 78 ARMS patients, using established reverse transcriptase polymerase chain reaction assays. All patients received central pathologic review and were treated using uniform protocols, allowing for meaningful outcome analysis. We examined the relationship between gene fusion status and clinical outcome in the ARMS cohort. RESULTS: PAX3-FKHR and PAX7-FKHR fusion transcripts were detected in 55% and 22% of ARMS patients, respectively; 23% were fusion-negative. All other RMS patients lacked transcripts, confirming the specificity of these alterations for ARMS. Fusion status was not associated with outcome differences in patients with locoregional ARMS. However, in patients presenting with metastatic disease, there was a striking difference in outcome between PAX7-FKHR and PAX3-FKHR patient groups (estimated 4-year overall survival rate of 75% for PAX7-FKHR v 8% for PAX3-FKHR; P =.0015). Multivariate analysis demonstrated a significantly increased risk of failure (P =.025) and death (P =.019) in patients with metastatic disease if their tumors expressed PAX3-FKHR. Among metastatic ARMS, bone marrow involvement was significantly higher in PAX3-FKHR-positive patients. CONCLUSION: Not only are PAX-FKHR fusion transcripts specific for ARMS, but expression of PAX3-FKHR and PAX7-FKHR identifies a very high-risk subgroup and a favorable outcome subgroup, respectively, among patients presenting with metastatic ARMS.

BACKGROUND: Intergroup Rhabdomyosarcoma Study (IRS)-II, (1978-1984) had the general goals of improving the survival and treatment of children with rhabdomyosarcoma (RMS). METHODS: Nine hundred ninety-nine previously untreated eligible patients entered the study after surgery and were randomized or assigned to therapy by IRS Clinical Group (I-IV), tumor site, and histologic type. Outcomes were compared between treatments and with results of IRS-I (1972-1978). RESULTS: Patients in Group I, excluding extremity alveolar (EA) RMS, were randomized to standard vincristine (V), dactinomycin (A), and cyclophosphamide (C) or standard VA. At 5 years, disease-free survival (DFS) and survival (S) rates were similar between VAC and VA (DFS: 80%, 70%, P = 0.47; S: 85%, 84%, P = 0.73). Patients in Group II, excluding EA RMS, received radiation and were randomized to intensive VA or repetitive-pulse VAC. Outcomes were similar for rates of DFS (69%, 74%, P = 0.83) and S (88%, 79%, P = 0.17). Patients in Group III, excluding certain pelvic tumors, received radiation and were randomized to repetitive-pulse VAC or repetitive-pulse VAdrC-VAC (Adr, Adriamycin [doxorubicin]). Complete remission (CR) rates were close at 74%, 78%, respectively (P = 0.32), as were percentages in CR (73%) and S (66%) rates; the latter outcomes were significantly better than IRS-I (CR: 56%, P < 0.001; S: 50%, P < 0.001). Central nervous system prophylaxis for Group III patients with cranial parameningeal sarcoma increased S rate to 67% from 45% in IRS-I (P < 0.001). Patients in Group IV received the same regimens as Group III; the CR rate was 53%, 38% remained in CR and S rate was 27% with and 26% without Adr (P = 0.90). At 5 years, S rate for IRS-II, including EA and all pelvic tumors, was 63%: an 8% increase over IRS-I (P < 0.001). Outcomes by primary site were as good as, or better than, the IRS-I experience. CONCLUSIONS: Combining all Groups and treatments in IRS-II, the major improvement in S rate at 5 years between studies was in nonmetastatic patients (71% for IRS-II versus 63% for IRS-I, P = 0.01).

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