AST/SGOT and ALT/SGPT ? . X ULN COHORT : AST (SGOT) and ALT (SGPT) =< X ULN within days of treatment initiation AST(SGOT)/ALT(SGPT) ? . X institutional ULN AST (SGOT) and ALT (SGPT) ? . x ULN. RANDOMIZED PHASE II CLINICAL TRIAL: Within days of registration: AST (SGOT) and ALT (SGPT) =< . X ULN OR =< X ULN for subjects with liver metastases AST/ALT (SGOT/SGPT) < ULN Serum aspartate transaminase (AST/SGOT) or alanine transaminase (ALT/SGPT) ? . x upper limit of normal (ULN). In the case of documented liver involvement by lymphoma, ALT/SGPT and AST/SGOT must be ? . x ULN. ENROLLMENT TO THE DOSE ESCALATION, EXPANSION AND PART II: AST (SGOT)/ALT (SGPT) =< . X ULN if hepatic metastases are present EXPANDED ACCESS COHORT: AST(SGOT)/ALT(SGPT) =< . x institutional ULN -OR- AST(SGOT)/ALT(SGPT)\t=< x institutional ULN if liver metastases are present AST (SGOT)/ ALT (SGPT): ? . x institutional ULN AST(SGOT)/ALT(SGPT) for patients with documented liver metastases, =< x institutional ULN AST (SGOT)/ALT (SGPT) ? X ULN; ? X ULN if there is liver involvement secondary to tumor AST (SGOT) and ALT (SGPT) ? . x ULN. AST/SGOT and ALT/SGPT ? . x ULN SGPT (ALT) ? U/L and AST (SGOT) and ALT (SGPT) =< x ULN in patients with documented hepatic involvement by lymphoma AST (aspartate transaminase or SGOT)/ALT (alanine aminotransferase or SGPT) ? . x ULN and total bilirubin ? . x ULN with no evidence of cholestasis Hepatic impairment, defined as AST (SGOT), or ALT (SGPT) > x institutional ULN, within days of initiation of protocol therapy or SGOT or SGPT > x ULN For Part B participants: SGPT (ALT) concentration < . x institutional ULN SGPT (ALT) ? U/L. RETREATMENT WITH MODIFIED T CELLS: ALT (SGPT): =< x ULN SGPT (ALT) and SGOT (AST) less than or equal to x normal for age B. Hepatic: Serum total bilirubin ?. x upper limit of normal (ULN), ALT (SGPT) and AST (SGOT) ?. x ULN. Aspartate aminotransferase (AST/SGOT) and alanine aminotransferase (ALT/SGPT) ? . upper limit of normal (ULN); if liver function abnormalities are due to underlying liver metastasis, AST (SGOT) and ALT (SGPT) ? ULN. AST / ALT (SGPT) <. x ULN AST(SGOT)/ALT(SGPT): ? x UNL REGISTRATION TO TREATMENT (STEP ): AST (SGOT) and ALT (SGPT) =< . X ULN OR =< X ULN for subjects with liver metastases, within days prior to first dose of pembrolizumab SGOT (AST) and SGPT (ALT) > x institutional ULN Serum AST/SGOT and ALT/SGPT ? . x ULN. Serum AST and ALT/SGPT ? . x ULN. AST(SGOT) and ALT(SGPT) <. x ULN REGISTRATION # - PRIOR TO CONSOLIDATION CHEMOTHERAPY: SGOT (AST) or SGPT (ALT) =< . x IULN AST (SGOT) and ALT (SGPT): ?.xULN OR ?xULN for subjects with liver metastases AST (SGOT) and ALT (SGPT) < X institutional ULN (for subjects with hepatic metastases < X institutional ULN) AST (SGOT) and ALT (SGPT) ? . x ULN AST/SGOT and ALT/SGPT ?.ULN ALT (SGPT) ? . X ULN for age AST/SGOT and ALT/SGPT > . x ULN AST (SGOT) and ALT (SGPT) ? . X ULN OR ? X ULN for patients with liver metastases Hepatic: Serum total bilirubin ?. x upper limit of normal (ULN), ALT (SGPT) and AST (SGOT) ?. x ULN. AST (SGOT) and ALT (SGPT) ? . x ULN); if liver metastases are present, then ? x ULN is allowed SGOT and SGPT >= x ULN; liver biopsy preferred for such patients Obtained within weeks from study entry: SGOT, SGPT =< X ULN if liver metastasis present The patient has serum total bilirubin < g/dL (unless the patient has a diagnosis of Gilbert's disease), SGOT (ALT) <.ULN, and SGPT (AST) <.ULN AST (SGOT) and ALT (SGPT) < = x ULN. AST (SGOT), ALT (SGPT) ? ULN is allowed: ALT (SGPT) ? the ULN; AST(SGOT)/ALT(SGPT) =< . X institutional ULN AST/ALT (SGOT/SGPT) < . x ULN for the reference laboratory or < x --ULN in the presence of liver metastases SELUMETINIB ARM: AST/SGOT or ALT/SGPT > . x ULN (>= ULN in presence of liver metastases) AST/SGOT and/or ALT/SGPT > . x ULN, (> x ULN if liver metastases present) Serum total bilirubin ? . x ULN and AST/SGOT and ALT/SGPT ? . x ULN or ? x ULN if liver metastases are present. Total bilirubin ? ULN, SGOT (AST) and SGPT (ALT)< . x ULN. AST and/or ALT may be up to X ULN if with known liver metastases provided bilirubin is normal. AST(SGOT)/ALT(SGPT) <. X institutional ULN unless due to disease SGPT (ALT) ? U/L and SGOT (AST) ? X ULN. (for the purpose of this study, the upper limit of normal [ULN] for SGPT [ALT] is U/L). Hepatic function: Serum total bilirubin ? . x ULN (upper limit of normal); AST (SGOT) and ALT (SGPT) ? x ULN, except in patients with tumor involvement of the liver who must have AST and ALT ? x ULN AST (SGOT) and ALT (SGPT) ? . x ULN. For subjects with documented liver metastases, ALT and AST ? ULN AST/SGOT, ALT/SGPT ?. x ULN, unless liver metastases are clearly present, then ?. x ULN AST(SGOT)/ALT(SGPT) ? X ULN (including patients with liver metastases) SGOT(AST) and SGPT(ALT) ? x ULN i.e. equivalent to ? Grade NCI-CTCAE v..