HCC 20: Lung and Other Severe Cancers

Relative factors by segment

Hierarchy

Hierarchical condition categories pay only the most severe manifestation of a disease. When HCC 17 (Cancer Metastatic to Lung, Liver, Brain, and Other Organs; Acute Myeloid Leukemia Except Promyelocytic) or HCC 18 (Cancer Metastatic to Bone, Other and Unspecified Metastatic Cancer; Acute Leukemia Except Myeloid) or HCC 19 (Myelodysplastic Syndromes, Multiple Myeloma, and Other Cancers) is also documented for the same beneficiary, HCC 20 is dropped from the score. When HCC 20 is present it drops HCC 21 (Lymphoma and Other Cancers), HCC 22 (Bladder, Colorectal, and Other Cancers), HCC 23 (Prostate, Breast, and Other Cancers and Tumors), so documenting the less severe condition alongside it adds nothing to payment but still matters for the clinical record.

ICD-10-CM codes that map to HCC 20

233 codes map to this category in the PY2027 initial mapping, concentrated in the C84 (55), C83 (45), C34 (16), C72 (14), C93 (12), C71 (10) code families. Descriptions are the CMS mapping descriptions for the FY2026 code set; a code that is deleted or split in the October code update stays valid for dates of service before the change.

Where these codes sat in the V22 model

Capturing and defending the category

A category counts for a payment year when a mapped diagnosis is documented at least once during the data collection year by an acceptable provider type at a face-to-face or audio-video encounter, and when the note shows the condition was monitored, evaluated, assessed or treated. Chronic conditions do not carry forward: a category that is not re-documented in the year drops out of the score, which is why annual wellness visits and problem-list reconciliation are where most recapture happens. Risk adjustment data validation audits sample enrollees and ask for the medical record behind each submitted category; an unsupported category is removed and, under the extrapolation rules, the error rate is applied across the contract. The QuickIntell risk adjustment product surfaces suspected and unsupported categories from the chart, and the HCC hub lists every V28 category with its factor and code count.

Related categories and reference

Frequently asked questions

Sources

Every figure on this page is taken from the CMS publications below, as released by the Centers for Medicare & Medicaid Services. Projection built 2026-10-02. Verify against the primary file before billing or contracting decisions.

• ICD-10-CM to CMS-HCC V28 mappings, payment year 2027 initial
  Version PY2027 initial ICD-10-CM mappings (dates of service 2026) · effective 2027-01-01 · file 2027 Initial ICD-10-CM Mappings.csvSHA-256 9c260b06d0dd2806…
• CMS-HCC V28 model software: labels, hierarchies and relative factors
  Version CMS-HCC V28 software V2826.115.T2 (PY2027 initial) · effective 2027-01-01 · file C2824T2N.csvSHA-256 20f38d537493b41c…