The Intergroup Rhabdomyosarcoma Study-II.
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).
Maurer
H M
HM
Medical College of Virginia/Virginia Commonwealth University, Richmond 23298.
Gehan
E A
EA
Beltangady
M
M
Crist
W
W
Dickman
P S
PS
Donaldson
S S
SS
Fryer
C
C
Hammond
D
D
Hays
D M
DM
Herrmann
J
J
D000293:Adolescent; D000328:Adult; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000009:adverse effects / Q000627:therapeutic use*; D002648:Child; D002675:Child, Preschool; D003131:Combined Modality Therapy; D003520:Cyclophosphamide / Q000008:administration & dosage; D003609:Dactinomycin / Q000008:administration & dosage; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007223:Infant; D008297:Male; D011379:Prognosis; D011878:Radiotherapy / Q000009:adverse effects; D012208:Rhabdomyosarcoma / Q000188:drug therapy / Q000401:mortality / Q000532:radiotherapy / Q000628:therapy*; D015996:Survival Rate; D014750:Vincristine / Q000008:administration & dosage
D003609:Dactinomycin; D014750:Vincristine; D003520:Cyclophosphamide