Malignancy

The ICD-10-CM provides two code sets to classify cancer (CA):

Categories C00-D09 are for active cancer or requiring active treatment. These categories include primary and secondary malignant neoplasms, and carcinoma-in-situs.

In order to use these categories, the clinical documentation must include:

• The term “active” and whether it is primary, secondary (metastasis) or in situ

• OR active treatment such as chemotherapy, radiation, immunotherapy or hormone therapy (e.g., Tamoxifen)

• OR if the patient refuses treatment, the term “watchful waiting” or that it is a contraindication due to age or other medical circumstance

Use the following codes as the first-listed or principal code when the encounter is solely for the administration of 1:

• Antineoplastic radiation therapy, Z51.0

• Antineoplastic chemotherapy, Z51.11

• And/or antineoplastic immunotherapy Z51.12

The malignancy for which the therapy is being administered should be assigned as a secondary diagnosis.

When an encounter is for a primary malignancy with metastasis and treatment is directed toward the metastatic (secondary) site only, the metastatic site is designated as the principal/first-listed diagnosis. The primary malignancy is coded as an additional code1

Codes under these categories (C00-D09) also have an impact in the Risk Adjustment Factor methodology. Here are the hierarchical conditions categories (HCCs):

1 2

This HCC (12) also includes certain nonmalignant neoplasms mainly related to the nervous system.

Categories Z85 and Z86 for history of a malignant neoplasm or carcinoma-in-situs

Use these categories when the CA has been eradicated from its site, there is no further treatment (of the malignancy) directed to that site, and there is no evidence of any existing malignancy. Also, these categories should be used when the documentation does not support an active code (above codes)1

If applicable, code first Z08 for follow-up examinations after active treatment including routine surveillance for recurrence of a previously treated malignancy.

References and Additional Notes:

* This tool is not intended to diagnose, evaluate, or treat patients. Each provider is responsible for the clinical and diagnostic decisions pertinent to their patient’s care. Always refer to the ICD-10-CM codebook for correct coding and more information about coding guidelines at: cdc.gov/nchs/icd/icd10cm.htm

1. RAF weight is based on a community-nondual-aged member, please refer to: https://www.cms.gov/Medicare/Health-Plans/MedicareAdvtgSpecRateStats/Risk-Adjustors Optum360, LLC. (2019). ICD-10-CM Expert for Hospitals