Evaluation of Dosing Procedures of Chemotherapy Treatment (Carboplatin) With the Contrast Agent Iohexol

Inclusion Criteria:

• Patients must have the psychological ability and general health that permitscompletion of the study requirements and required follow up

• For men who are sexually active, the need for use of medically acceptablecontraception will be dictated by the primary treatment plan/protocol

• Study accrual was closed to women on 08/18/2021 and accrual is now only open tomales in order to meet accrual goals and study objectives. (11-AUG-2021)

• Male sex

• Any patients who will receive treatment with intravenous carboplatin (any AUC, anycycle) on a National Cancer Institute (NCI)-sponsored National Clinical TrialNetwork (NCTN)-, Experimental Therapeutics Clinical Trials Network (ETCTN)-, trial,local trial, or through standard of care

• Age >= 18

• The patient or a legally authorized representative must provide study-specificinformed consent prior to study entry

Exclusion Criteria:

• Treated at an institute where creatinine is not measured with an IDMS calibratedassay

• History of allergic reactions to computed tomography (CT) contrast, iodine orshellfish, or history of anaphylactic reaction to any food item

• Recent (last 6 months) episode of acute kidney injury, have sickle cell disease, orhave current indwelling nephrostomy tubes

• Edema beyond trace edema, because this will impact iohexol equilibration anddistribution

• Ascites (including pleural effusion) beyond trace ascites, because this will impactiohexol equilibration and distribution

• Whole- or part-limb amputees, because this will impact iohexol equilibration anddistribution

• Inability to maintain a constant dose and schedule of anti-inflammatory agents,diuretics, angiotensin II receptor blockers (ARB) and angiotensin converting enzymeinhibitors (ACEi) for one week prior to study visit, as this impacts renal function.If the patient is on a nonsteroidal anti-inflammatory drug (NSAID), diuretic, ARB orACEi, they are eligible as long as these agents are taken on a set schedule for 7 ormore days prior to study (and not on an "as needed" basis as that can causefluctuations in renal function)

• Inadequate venous access to obtain pharmacokinetic (PK) specimens

• Multinodular goiter, Graves' disease or autoimmune thyroiditis, per iohexol packageinsert (hypothyroidism is allowed)