C53.1
BillableMalignant neoplasm of exocervix
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is C53.1 an HCC code?
Yes. C53.1 maps to Bladder, Colorectal, and Other Cancers under the CMS-HCC V28 risk adjustment model (and Colorectal, Bladder, and Other Cancers under V24).
HCC Category Mapping
RAF weights shown are the community, non-dual, aged base weights from the CMS risk adjustment model file. Actual per-patient RAF contribution depends on member segment, interactions, and the model year used by the payer. V28 is the CMS-HCC model phased in over payment years 2024–2026; V24 remains in use during the transition and for historical data.
MEAT Criteria for C53.1
For C53.1to count as a valid HCC diagnosis in a given encounter, the provider's documentation must show MEAT: Monitor, Evaluate, Assess, or Treat. A diagnosis from a prior year does not carry forward automatically — it has to be re-documented and supported each calendar year.
- MMonitor: signs, symptoms, disease progression, or lab trending documented in the note
- EEvaluate: test results, medication response, or physical findings reviewed by the provider
- AAssess: explicit mention in the assessment or plan with acknowledgment of status
- TTreat: medication, referral, procedure, therapy, or counseling tied to the diagnosis
Only one of M/E/A/T is required to support the code, but the documentation must be specific enough to show that the provider actually addressed C53.1 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
C53.1 is the ICD-10-CM diagnosis code for malignant neoplasm of exocervix. Cancer that occurs in the exocervix, the outer portion of the cervix that is visible during examination. C53.1 sits in the ICD-10-CM chapter for neoplasms (c00-d49), within the section covering malignant neoplasms of female genital organs (c51-c58).
Under the CMS-HCC V28 risk adjustment model, C53.1 maps to Bladder, Colorectal, and Other Cancers (HCC 22) with a community, non-dual, aged base RAF weight of 0.363. Under the older CMS-HCC V24 model, C53.1 maps to Colorectal, Bladder, and Other Cancers (HCC 11) with a community, non-dual, aged base RAF weight of 0.307. V28 is the CMS-HCC risk adjustment model that reached 100% phase-in for payment year 2026, replacing V24 which was used during the PY2024–PY2025 transition.
Squamous cell carcinoma is the predominant histology; verify and document the specific type. Because C53.1 maps to a payment HCC, the provider's documentation must satisfy MEAT criteria (Monitor, Evaluate, Assess, or Treat) for the encounter to count toward the patient's Medicare Advantage risk adjustment score. When documentation is ambiguous, coders should issue a provider query rather than assume the highest-specificity variant.
HCC Buddy maintains structured V28 and V24 mapping, RAF weights, and MEAT documentation criteria for C53.1 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •Squamous cell carcinoma is the predominant histology; verify and document the specific type
- •This is the most common site for cervical cancer; ensure HPV status is documented when available
Clinical Significance
Malignant neoplasm of the exocervix involves the outer portion of the cervix that is visible during speculum examination. Exocervical cancers are predominantly squamous cell carcinomas and are strongly associated with Human Papillomavirus infection. This is the most common location for cervical cancer and the area most effectively screened by Pap smear and colposcopy.
Documentation Requirements
- ✓Specific site confirmed as exocervix (ectocervix or portio vaginalis)
- ✓Histological type (squamous cell carcinoma predominates)
- ✓FIGO staging
- ✓Depth of stromal invasion
- ✓Parametrial involvement assessment
- ✓Lymph node status
- ✓Human Papillomavirus status and type if documented
Commonly Confused Codes
- •C53.0 — Malignant neoplasm of endocervix; inner canal versus outer surface — different sites with different predominant histologies
- •C53.8 — Overlapping sites of cervix; use when tumor involves both endocervix and exocervix
- •C53.9 — Cervix uteri, unspecified; use only when exocervix is not specifically identified
- •D06.0/D06.1 — Carcinoma in situ of cervix; preinvasive disease — not the same as invasive cancer