<prompt> The commonest side effect of cisplatinum in a patient using it for esophageal carcinoma is :Acute tubular necrosisThrombocytopeniaHepatic failureCardiomyopathy  <response>: Answer is A Acute tubular necrosis The most impoant toxity of cisplatinum is renal impairment - KDT 7th777 Acute tubular necrosis is a manifestation of renal impairment and hence the answer. 