C63.8 ICD-10-CM Code: Malignant neoplasm of overlapping sites of male genital organs
HCC Buddy Code Card
Digital ICD-10 code-book layout with official code detail, always-visible risk models, Code Trumping, and Buddy coding guidance.
FY 2026 Apr update / Neoplasms (C00-D49) / Malignant neoplasms of male genital organs (C60-C63)
C63.8
Billable / SpecificICD-10-CMOfficial ICD-10-CMCodebook guidanceMalignant neoplasm of overlapping sites of male genital organs
Cancer involving multiple male genital organs at the same time, such as both the testicle and epididymis.
Buddy Insight
This code captures malignancies involving two or more contiguous male genital organ sites when the point of origin cannot be determined.
CMS-HCC V28
MappedHCC 23
RAF 0.251
CMS-HCC V24
MappedHCC 12
RAF 0.150
ACA/HHS
00
RAF 0
ESRD/PACE
MappedHCC 12
RAF 0.0
RXHCC
MappedHCC 22
RAF 0.0
Code Trumping
Basket needed
Code Book Path
Inclusion Terms
Official- Primary malignant neoplasm of two or more contiguous sites of male genital organs whose point of origin cannot be determined
Excludes 2
OfficialICD-10-CM does not list Excludes 2 notes for C63.8 in this effective period.
Related Child Codes
Includes
OfficialICD-10-CM does not list Includes notes for C63.8 in this effective period.
Excludes 1
OfficialICD-10-CM does not list Excludes 1 notes for C63.8 in this effective period.
Code First
OfficialICD-10-CM does not list Code First sequencing instructions for C63.8 in this effective period.
Use Additional
OfficialICD-10-CM does not list Use Additional Code instructions for C63.8 in this effective period.
Code Also
OfficialICD-10-CM does not list Code Also instructions for C63.8 in this effective period.
Buddy Documentation Tip
MEAT Support
Audit Caution
Common Mistakes
Last updated: FY2026 ICD-10-CM Apr update, Apr 1, 2026 through Sep 30, 2026. CMS-HCC V28 is 100% phased in for payment year 2026.
Is C63.8 an HCC code?
Yes. C63.8 maps to Melanoma and Other Skin Cancers under the CMS-HCC V28 risk adjustment model (and Breast, Prostate, and Other Cancers and Tumors 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 C63.8
For C63.8to 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 C63.8 during that encounter, not just copy-forwarded from a problem list.
What This Code Means
C63.8 is the ICD-10-CM diagnosis code for malignant neoplasm of overlapping sites of male genital organs. Cancer involving multiple male genital organs at the same time, such as both the testicle and epididymis. C63.8 sits in the ICD-10-CM chapter for neoplasms (c00-d49), within the section covering malignant neoplasms of male genital organs (c60-c63).
Under the CMS-HCC V28 risk adjustment model, C63.8 maps to Melanoma and Other Skin Cancers (HCC 23) with a community, non-dual, aged base RAF weight of 0.251. Under the older CMS-HCC V24 model, C63.8 maps to Breast, Prostate, and Other Cancers and Tumors (HCC 12) with a community, non-dual, aged base RAF weight of 0.150. 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.
This code is used when the tumor involves two or more contiguous male genital sites. Because C63.8 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 C63.8 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •This code is used when the tumor involves two or more contiguous male genital sites
- •Document which specific organs are involved to support medical necessity
Clinical Significance
This code captures malignancies involving two or more contiguous male genital organ sites when the point of origin cannot be determined. It indicates a tumor mass spanning multiple structures (e.g., testis and epididymis, or prostate and seminal vesicles as a primary of indeterminate origin). This is distinct from metastatic spread and from extension of a known primary.
Documentation Requirements
- ✓Documentation identifying which specific male genital organs are involved
- ✓Pathologic evidence of contiguous tumor involvement across multiple sites
- ✓Statement that the point of origin cannot be determined
- ✓Staging information
- ✓Treatment plan
Commonly Confused Codes
- •C63.7 — Other specified male genital organ; use for a single specified structure
- •C63.9 — Unspecified male genital organ; overlapping is more specific than unspecified
- •C60.8 — Overlapping sites of penis; use when overlapping is confined to penile subsites
- •C61/C62/C63.0x — Specific organ codes; use when a primary site can be identified