This phase II trial investigates evolutionary inspired therapy in treating fusion positive rhabdomyosarcoma that is newly diagnosed and has spread to other places in the body (metastatic). Chemotherapy drugs, such as vinorelbine, vincristine sulfate, and actinomycin D, work in different ways to stop the growth of tumor cells, either by killing the cells, by stopping them from dividing, or by stopping them from spreading. Cyclophosphamide is used to decrease the body's immune response and may inhibit DNA replication and initiate cell death. This study is being done to determine which of 4 different therapeutic treatments will have the best chance of the disease not worsening or coming back.

This phase III trial compares the effect of radiation therapy combined with hormonal therapy versus hormonal therapy alone in treating patients with low risk, early stage breast cancer with Oncotype Dx Recurrence =< 18. Oncotype DX is a laboratory test which results in a score that is used to help predict whether breast cancer will spread to other parts of the body or come back. Radiation therapy uses high doses of radiation to kill cancer cells and shrink tumors but may result in some side effects. Hormones called estrogen and progesterone may contribute to the growth of breast tumor cells. Hormone therapy, also called endocrine therapy, may stop the growth of tumor cells by blocking or removing these hormones. This clinical trial may help researchers understand if patients with low-risk, early stage breast cancer who have Oncotype recurrence score of =< 18 can safely omit radiation therapy and only be treated with hormonal therapy without losing any radiation treatment benefit.

Rhabdomyosarcoma is a type of cancer that occurs in the soft tissues in the body. This phase III trial aims to maintain excellent outcomes in patients with very low risk rhabdomyosarcoma (VLR-RMS) while decreasing the burden of therapy using treatment with 24 weeks of vincristine and dactinomycin (VA) and examines the use of centralized molecular risk stratification in the treatment of rhabdomyosarcoma. Another aim of the study it to find out how well patients with low risk rhabdomyosarcoma (LR-RMS) respond to standard chemotherapy when patients with VLR-RMS and patients who have rhabdomyosarcoma with DNA mutations get separate treatment. Finally, this study examines the effect of therapy intensification in patients who have RMS cancer with DNA mutations to see if their outcomes can be improved.