164 Malignant neoplasm of thymus, heart, and mediastinum (164.0-164.9) ICD-9-CM
The 164.0-164.9 block classified 164 malignant neoplasm of thymus, heart, and mediastinum with 6 legacy diagnosis codes. None remain valid for claim submission; each code below links to its reference page with the official ICD-10-CM replacement under the CMS General Equivalence Mappings.
Retired Code Set
ICD-9-CM stopped being valid for U.S. claims with dates of service on or after October 1, 2015, when ICD-10-CM replaced it. Use this index for historical lookups and crosswalking; for current coding, start from the ICD-10-CM codes list or the ICD-9 / ICD-10 converter.
Legacy Codes in the 164.0-164.9 Block 6 codes
None of these codes remain valid for claim submission. Each code page shows its ICD-10-CM replacement under the CMS General Equivalence Mappings.
Questions About This Page
Are the 164.0-164.9 codes still billable?
No. Every code in this block became invalid for U.S. claims after September 30, 2015. Each code page linked above shows the ICD-10-CM replacement CMS assigned in the General Equivalence Mappings, and the ICD-9 / ICD-10 converter translates any of them directly.
What did the 164.0-164.9 block classify?
The block classified 164 malignant neoplasm of thymus, heart, and mediastinum with 6 codes in the final ICD-9-CM release. It sat under Neoplasms (140–239) in the legacy hierarchy.
Related References
Source: final CMS ICD-9-CM release (version date October 1, 2014). Retired from U.S. claims after September 30, 2015.
