Vemurafenib in Treating Patients With Relapsed or Refractory Advanced Solid Tumors, Non-Hodgkin Lymphoma, or Histiocytic Disorders With BRAF V600 Mutations (A Pediatric MATCH Treatment Trial)

PRIMARY OBJECTIVE: I. To determine the objective response rate (ORR; complete response + partial response) in pediatric patients treated with vemurafenib with advanced solid tumors (including central nervous system \[CNS\] tumors), lymphomas or histiocytic disorders that harbor activating BRAF V600 mutations. SECONDARY OBJECTIVES: I. To estimate the progression free survival in pediatric patients treated with vemurafenib with advanced solid tumors (including CNS tumors), lymphomas or histiocytic disorders that harbor activating BRAF V600 mutations. II. To obtain information about the tolerability of vemurafenib in children with relapsed or refractory cancer. EXPLORATORY OBJECTIVE: I. To explore approaches to profiling changes in tumor genomics over time through evaluation of circulating tumor deoxyribonucleic acid (DNA). OUTLINE: Patients receive vemurafenib orally (PO) twice daily (BID) on day 1-28. Cycles repeat every 28 days for up to 2 years in the absence of disease progression or unacceptable toxicity.