Neoplasms
This chapter covers ICD-10-CM codes in the range C00-D49 for neoplasms. Includes all types of malignant and benign neoplasms, organized by anatomical site and behavior.
Chapter Overview
Key Statistics
- •Contains 21 categories and 135 total codes
- •Includes 123 billable codes and 12 non-billable codes
- •Chapter range: C00-D49
Clinical Relevance
Essential for oncology coding covering malignant, benign, and uncertain behavior neoplasms. Critical for cancer registries, treatment planning, and oncology billing.
Documentation Requirements
Requires histologic type, primary vs secondary site, grade, stage, and functional activity status. Morphology codes often required for cancer registry reporting.
Special Considerations
Functional activity must be documented separately. Primary site sequencing rules are complex and depend on treatment focus.
Categories in this Chapter
Malignant neoplasms of lip, oral cavity and pharynx
Malignant neoplasms of digestive organs
Malignant neoplasms of respiratory and intrathoracic organs
Malignant neoplasms of bone and articular cartilage
Melanoma and other malignant neoplasms of skin
Malignant neoplasms of mesothelial and soft tissue
Malignant neoplasms of breast
Malignant neoplasms of female genital organs
Malignant neoplasms of male genital organs
Malignant neoplasms of urinary tract
Malignant neoplasms of eye, brain and other parts of central nervous system
Malignant neoplasms of thyroid and other endocrine glands
Malignant neoplasms of ill-defined, other secondary and unspecified sites
Malignant neuroendocrine tumors
Secondary neuroendocrine tumors
Malignant neoplasms of lymphoid, hematopoietic and related tissue
In situ neoplasms
Benign neoplasms, except benign neuroendocrine tumors
Neoplasms of uncertain behavior, polycythemia vera and myelodysplastic syndromes
Benign neuroendocrine tumors
Neoplasms of unspecified behavior
Chapter-Specific Coding Guidelines
General Guidelines for Neoplasms:
- Primary malignant neoplasms are coded to the anatomical site of origin
- Secondary neoplasms require both primary site and metastatic site coding
- Use additional codes for tumor morphology when available
- Sequence codes according to the reason for the encounter
Documentation Requirements:
- •Primary site of neoplasm must be clearly identified
- •Histologic type and grade when available
- •Staging information (TNM staging)
- •Treatment status (active treatment, remission, etc.)
- •Complications or adverse effects of treatment
Sequencing Rules:
- Principal diagnosis should reflect the reason for admission/encounter
- Active treatment: sequence the malignancy as principal diagnosis
- Complications from treatment: sequence complication first
- Follow-up care: use Z51.- codes as appropriate
When to Use:
- ✓When documenting primary malignant neoplasms
- ✓For secondary (metastatic) neoplasms
- ✓During active cancer treatment
- ✓For complications directly related to malignancy
When NOT to Use:
- ✗Personal history of malignancy (use Z85.- codes)
- ✗Family history of malignancy (use Z80.- codes)
- ✗Screening encounters (use Z12.- codes)
- ✗Benign neoplasms (use D10-D36 codes)
Special Considerations:
- ⚠Multiple primary sites require separate codes
- ⚠Metastatic disease coding requires specific sequencing
- ⚠Treatment complications may take precedence
- ⚠Prophylactic procedures have specific coding rules
Version Updates
The 2025 updates focus on precision oncology coding, immunotherapy treatments, and enhanced staging documentation.
Recent Updates:
CAR-T Cell Therapy Coding Updates
New codes for chimeric antigen receptor T-cell therapy complications and monitoring
Impact: Affects coding for advanced cancer treatments
Tumor Marker Integration
Enhanced coding for molecular tumor markers and genetic testing results
Impact: Improved precision medicine documentation
Implementation Guidance:
- •Review oncology coding practices for new immunotherapy codes
- •Update templates for genetic testing documentation
- •Train staff on precision oncology coding requirements
- •Implement quality checks for staging completeness
Upcoming Changes:
- →Expanded liquid biopsy coding expected in 2026
- →New categories for personalized medicine treatments
- →Enhanced coding for minimal residual disease
Related Resources
Comprehensive resources for oncology coding, staging guidelines, and treatment documentation.
Official Documentation:
Related Chapters:
Tools and References:
Frequently Asked Questions
How do I code a patient with metastatic cancer when the primary site is unknown?
Use C80.1 for malignant neoplasm, unspecified, and code the metastatic sites as secondary neoplasms (C77-C79).
What's the difference between active treatment and follow-up care coding?
Active treatment sequences the malignancy first. Follow-up care uses Z08 (encounter for follow-up examination after completed treatment) with the history code Z85.-.
How do I code complications from cancer treatment?
Sequence the complication code first, followed by the malignancy code. Use T80-T88 for treatment complications when appropriate.