This phase III trial compares the safety and effect of adding vinorelbine to vincristine, dactinomycin, and cyclophosphamide (VAC) for the treatment of patients with high risk rhabdomyosarcoma (RMS). High risk refers to cancer that is likely to recur (come back) after treatment or spread to other parts of the body. This study will also examine if adding maintenance therapy after VAC therapy, with or without vinorelbine, will help get rid of the cancer and/or lower the chance that the cancer comes back. Vinorelbine and vincristine are in a class of medications called vinca alkaloids. They work by stopping cancer cells from growing and dividing and may kill them. Dactinomycin is a type of antibiotic that is only used in cancer chemotherapy. It works by damaging the cell's deoxyribonucleic acid (DNA) and may kill cancer cells. Cyclophosphamide is in a class of medications called alkylating agents. It works by damaging the cell's DNA and may kill cancer cells. It may also lower the body's immune response. Vinorelbine, vincristine, dactinomycin and cyclophosphamide are chemotherapy medications that work in different ways to stop the growth of cancer cells, either by killing the cells, by stopping them from dividing, or by stopping them from spreading. This trial may have the potential to eliminate rhabdomyosarcoma for a long time or for the rest of patient's life.

PRIMARY OBJECTIVE:

I. To compare event-free survival (EFS) of patients with high-risk rhabdomyosarcoma (HR-RMS) treated with vinorelbine, dactinomycin and cyclophosphamide (VINO-AC) followed by 24 weeks of vinorelbine and oral cyclophosphamide (VINO-CPO) maintenance therapy to that of patients treated with vincristine, dactinomycin and cyclophosphamide (VAC) followed by 24 weeks of VINO-CPO maintenance therapy.

SECONDARY OBJECTIVES:

I. To assess the safety and feasibility of administering VINO-AC in newly diagnosed patients with HR-RMS.

II. To describe the toxicity experience of patients with HR-RMS treated with VINO-AC compared to VAC.

III. To compare overall survival (OS) of patients with HR-RMS treated with VINO AC followed by 24 weeks of VINO-CPO maintenance therapy to that of patients treated with VAC followed by 24 weeks of VINO-CPO maintenance therapy.

IV. To compare objective radiologic response rates at week 12 between patients with HR-RMS treated with VINO-AC to those treated with VAC.

V. To determine whether the addition of 24 weeks of VINO-CPO maintenance therapy improves EFS in patients with HR-RMS when compared to historical controls.

VI. To determine the association between circulating tumor-derived deoxyribonucleic acid (ctDNA) levels at diagnosis and during initial chemotherapy and event-free survival (EFS) in patients with HR RMS.

VII. To prospectively validate the prognostic impact of genomic variants in HR RMS.

EXPLORATORY OBJECTIVE:

I. To collect serial blood samples and tumor tissue for banking at baseline, during treatment, at the end of therapy, and at the time of progression for future tumor and liquid biopsy studies.

OUTLINE: Patients are randomized to 1 of 2 arms.

ARM A: Patients receive vincristine sulfate intravenously (IV) on days 1, 8 and 15 of cycles 1-4, 7, 8, 11, and 12, and day 1 of cycles 5, 6, 9, 10, 13, and 14. Patients also receive dactinomycin IV over 1-15 minutes or IV push (IVP) over 1-5 minutes on day 1 of cycles 1-5, 8-10, and 11-14, and cyclophosphamide IV over 60 minutes on day 1 of each cycle. Treatment repeats every 21 days for up to 14 cycles in the absence of disease progression or unacceptable toxicity. Patients also undergo radiation therapy on weeks 13 and 40.

ARM B: Patients receive vinorelbine tartrate IV over 6-10 minutes on days 1 and 8, vincristine sulfate IV on day 15, dactinomycin IV over 1-15 minutes or IVP over 1-5 minutes on day 1 of cycles 1-5 and 8-14, and cyclophosphamide IV over 60 minutes on day 1. Treatment repeats every 21 days for up to 14 cycles in the absence of disease progression or unacceptable toxicity. Patients also undergo radiation therapy on weeks 13 and 40.

MAINTENANCE: All patients receive vinorelbine tartrate IV over 6-10 minutes on days 1, 8, and 15 and cyclophosphamide orally (PO) on days 1-28. Treatment repeats every 28 days for up to 6 cycles in the absence of disease progression or unacceptable toxicity.

Patients in both arms undergo computed tomography (CT), magnetic resonance imaging (MRI), positron emission tomography (PET), x-ray imaging, and/or bone scan, as well as blood sample collection throughout the trial. Patients may also undergo bone marrow aspiration and/or biopsy as clinically indicated

After completion of study treatment, patients are followed up every 3 months for year 1, every 4 months for years 2-3, and every 6 months for years 4-5.

Inclusion Criteria:

• Patients must be =< 50 years of age at the time of enrollment

• Patients with newly diagnosed RMS of any subtype, except adult-type pleomorphic, based upon institutional histopathologic classification are eligible to enroll on the study based upon stage, group, and age, as below. FOXO1 fusion status must be determined by week 4 (day 28) of therapy. RMS types included under embryonal RMS (ERMS) include those classified in the 1995 International Classification of Rhabdomyosarcoma (ICR) as ERMS (classic, spindle cell, and botryoid variants), which are reclassified in the 2020 World Health Organization (WHO) Classification as ERMS (classic, dense and botryoid variants) and spindle cell/sclerosing RMS (encompassing the historical spindle cell ERMS variant and the newly recognized sclerosing RMS variant). Classification of alveolar RMS (ARMS) in the 2020 WHO Classification is the same as in the ICR and includes classic and solid variants

  • ERMS

    • Stage 4, group IV, >= 10 years of age

  • ARMS

    • Stage 4, group IV Patients will be eligible to remain on protocol therapy based upon stage, group, and age

• Bone marrow metastatic disease is based on morphologic evidence of RMS based on hematoxylin and eosin (H&E) stains. In the absence of morphologic evidence of marrow involvement on H&E, patients with bone marrow involvement detected ONLY by flow cytometry, reverse transcriptase (RT)-polymerase chain reaction (PCR), fluorescence in situ hybridization (FISH), or immunohistochemistry will NOT be considered to have clinical bone marrow involvement for the purposes of this study

• Creatinine clearance or radioisotope glomerular filtration rate (GFR) >= 70 mL/min/1.73 m^2 or a serum creatinine based on age/sex as follows (must be performed within 7 days prior to enrollment):

  • Age; Maximum serum creatinine (mg/dL)
  • 1 month to < 6 months; 0.4 mg/dL (male); 0.4 mg/dL (female)
  • 6 months to < 1 year; 0.5 mg/dL (male); 0.5 mg/dL (female)
  • 1 to < 2 years; 0.6 mg/dL (male); 0.6 mg/dL (female)
  • 2 to < 6 years; 0.8 mg/dL (male); 0.8 mg/dL (female)
  • 6 to < 10 years; 1 mg/dL (male); 1 mg/dL (female)
  • 10 to < 13 years; 1.2 mg/dL (male); 1.2 mg/dL (female)
  • 13 to < 16 years; 1.5 mg/dL (male); 1.4 mg/dL (female)
  • >= 16 years; 1.7 mg/dL (male); 1.4 mg/dL (female)

• Total bilirubin =< 1.5 x upper limit of normal (ULN) for age (must be performed within 7 days prior to enrollment)

  • If there is evidence of biliary obstruction by tumor, then total bilirubin must be < 3 x ULN for age

• All patients and/or their parents or legal guardians must sign a written informed consent

• All institutional, Food and Drug Administration (FDA), and National Cancer Institute (NCI) requirements for human studies must be met

Exclusion Criteria:

• Patients with evidence of uncontrolled infection are not eligible

• RMS that is considered a second malignancy and previous cancer(s) that were treated with chemotherapy and/or radiation. Surgical resection alone of previous cancer(s) is allowed

• Patients with central nervous system involvement of RMS as defined below:

  • Malignant cells detected in cerebrospinal fluid
  • Intra-parenchymal brain metastasis separate and distinct from primary tumor (i.e., direct extension from parameningeal primary tumors is allowed).
  • Diffuse leptomeningeal disease

• Patients who have received any chemotherapy (excluding steroids) and/or radiation therapy for RMS prior to enrollment.

  • Note: the following exception:

    • Patients requiring emergency radiation therapy for RMS. These patients are eligible, provided they are consented to ARST2031 prior to administration of radiation

  • Note: Patients who have received or are receiving chemotherapy or radiation for non-malignant conditions (e.g. autoimmune diseases) are eligible. Patients must discontinue chemotherapy for non-malignant conditions prior to starting protocol therapy

• Vincristine and vinorelbine are sensitive substrates of CYP450 3A4 isozyme. Patients must not have received drugs that are moderate to strong CYP3A4 inhibitors and inducers within 7 days prior to study enrollment

• Female patients who are pregnant since fetal toxicities and teratogenic effects have been noted for several of the study drugs. A pregnancy test is required for female patients of childbearing potential

• Lactating females who plan to breastfeed their infants

• Sexually active patients of reproductive potential who have not agreed to use an effective contraceptive method for the duration of their study participation