ICD-10-CM > Z00-Z99 > Z77-Z99 > Z79 > Z79.6 > Z79.63 > Z79.634 Z79.634 Long term (current) use of topoisomerase inhibitor Billable/Specific Copy Code Copy Description Applicable To Long term (current) use of etoposideLong term (current) use of irinotecanLong term (current) use of topotecan