C76.1
BillableMalignant neoplasm of thorax
HCC Category Mapping
V28HCC 23 — Melanoma and Other Skin Cancers
0.251V24HCC 12 — Breast, Prostate, and Other Cancers and Tumors
0.150ESRDHCC 12 — Breast, Prostate, and Other Cancers and Tumors
0.000RxHCCHCC 22 — Cancer, Other Specified Sites
0.000What This Code Means
A malignant (cancerous) tumor located in the chest area, but the specific organ or tissue of origin is not further specified.
Coding Tips
- •Use this code when thoracic malignancy is confirmed but the specific organ (lung, heart, esophagus, etc.) cannot be determined
- •Review imaging and pathology reports to identify the specific organ and assign a more precise code if possible
Clinical Significance
Malignant neoplasm of the thorax (ill-defined site) represents cancer in the thoracic region where the specific organ of origin cannot be identified. This differs from lung cancer, mediastinal tumors, or pleural malignancies which have specific codes. It applies to overlapping thoracic malignancies where the primary origin is indeterminate after workup.
Documentation Requirements
- ✓Documentation confirming thoracic malignancy without identifiable specific organ of origin
- ✓Imaging (CT chest, PET scan) documenting tumor extent
- ✓Pathology with histological type that may help identify tissue of origin
- ✓Documentation of workup performed to identify the primary site
- ✓Treatment plan despite unknown primary
Commonly Confused Codes
C34.90 — Malignant neoplasm of unspecified part of bronchus/lung: Use when lung origin is documentedC38.1-C38.3 — Malignant neoplasm of mediastinum: Use when mediastinal origin is specifiedC45.0 — Mesothelioma of pleura: Specific pleural malignancyC78.00-C78.02 — Secondary malignant neoplasm of lung: Metastatic disease to thoraxC80.0 — Disseminated malignant neoplasm: Use when cancer is widely disseminated
Code Hierarchy
└C76Malignant neoplasm of other and ill-defined sites└C76.1Malignant neoplasm of thorax
└C76.1Malignant neoplasm of thorax