2027 ICD-10-CM Diagnosis Code C63.00Malignant neoplasm of unspecified epididymis

ICD-10-CM Codes›C00–D49›C60-C63›C63

ICD-10-CM C63.00
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

C63.00 is a billable ICD-10-CM diagnosis code for malignant neoplasm of unspecified epididymis. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 715 through 716, 722 through 724. Coders also document this condition as carcinoma of epididymis and spermatic cord. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Male reproductive system cancers - all other types.

For Medicare Advantage risk adjustment, C63.00 maps to CMS-HCC Category 23 (Prostate, Breast, and Other Cancers and Tumors) under the V28 model, adding a risk factor of about 0.186 for a community, non-dual, aged beneficiary in payment year 2027.

Code Identity

ICD-10-CM Code
C63.00
Billable Status
Yes — Valid for Submission
Code Describes
Malignant neoplasm of unspecified epididymis
Short Description
Malignant neoplasm of unspecified epididymis
Same as the full description in the CMS dataset.
Parent Code
C63.0
Malignant neoplasm of epididymis

Code Classification

ChapterC00–D49Neoplasms
SectionC60-C63Malignant neoplasms of male genital organs
CategoryC63Malignant neoplasm of other and unspecified male genital organs
This CodeC63.00Malignant neoplasm of unspecified epididymis

Medicare Risk Adjustment (HCC)Billing

C63.00 maps to a payment category in the CMS-HCC model used to risk-adjust Medicare Advantage payments. Weights are the published community factors for payment year 2027.

CMS-HCC V28 Category (Payment Model)
HCC 23— Prostate, Breast, and Other Cancers and Tumors
Payment HCC · PY 2027 one of 234 ICD-10-CM codes in this category
Risk Adjustment Factor (RAF) Weight
+0.186
community, non-dual, aged · ranges 0.186–0.237 across segments
Hierarchy
Superseded by HCC 17, HCC 18, HCC 19, HCC 20, HCC 21, and HCC 22
a more severe related category takes the payment when both are reported
Prior Model (CMS-HCC V24)
HCC 12
V24 retired V28 pays 100% of MA risk scores since PY 2026
Other CMS Models
PACE (CMS-HCC V22): HCC 12 · ESRD (V21): HCC 12 · ESRD (V24): HCC 12
ESRD V21 weights: 0.046 dialysis, 0.156–0.194 functioning graft · ESRD V24 weights: 0.045 dialysis, 0.162–0.219 functioning graft
Part D (RxHCC)
RxHCC 22 — Prostate, Breast, Bladder, and Other Cancers and Tumors
also risk-adjusts in the Part D prescription drug model (V08)

Source: CMS Payment Year 2027 risk adjustment mappings and model software. Weights are relative factors, not dollar amounts; a beneficiary's total RAF also includes demographics and interactions. Browse all CMS-HCC categories.

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Carcinoma of epididymis and spermatic cord
  • Malignant neoplasm of epididymis
  • Malignant neoplasm of spermatic cord
  • Primary carcinoma of epididymis and spermatic cord
  • Primary malignant neoplasm of epididymis
  • Primary malignant neoplasm of spermatic cord

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to C63.00: its own notes plus those printed at block C60-C63 and Chapter 2. A note printed at a category, block or chapter applies to every code under it.

Includes

Further defines, or gives examples of, the content of the category.

From Block C60-C63 Malignant neoplasms of male genital organs applies to 25 codes
  • malignant neoplasm of skin of male genital organs

Notes

General instructions on how these codes are used.

From Chapter 2 (C00-D49) Neoplasms applies to 1,730 codes
  • Functional activity
  • All neoplasms are classified in this chapter, whether they are functionally active or not. An additional code from Chapter 4 may be used, to identify functional activity associated with any neoplasm.
  • Morphology [Histology]
  • Chapter 2 classifies neoplasms primarily by site (topography), with broad groupings for behavior, malignant, in situ, benign, etc. The Table of Neoplasms should be used to identify the correct topography code. In a few cases, such as for malignant melanoma and certain neuroendocrine tumors, the morphology (histologic type) is included in the category and codes.
  • Primary malignant neoplasms overlapping site boundaries
  • A primary malignant neoplasm that overlaps two or more contiguous (next to each other) sites should be classified to the subcategory/code .8 ('overlapping lesion'), unless the combination is specifically indexed elsewhere. For multiple neoplasms of the same site that are not contiguous, such as tumors in different quadrants of the same breast, codes for each site should be assigned.
  • Malignant neoplasm of ectopic tissue
  • Malignant neoplasms of ectopic tissue are to be coded to the site mentioned, e.g., ectopic pancreatic malignant neoplasms are coded to pancreas, unspecified (C25.9).

Source: CMS ICD-10-CM Tabular List. How to read instructional notes.

Referenced in Other NotesGuidance

Instructional notes printed at other codes that name C63.00, its category, or a range that includes it.

Applicable To 2

These notes mention C63.00.

  • Z80.4 Family history of malignant neoplasm of genital organs
    Conditions classifiable to C51-C63 names C51-C63, which includes this code
  • Z85.4 Personal history of malignant neoplasm of genital organs
    Conditions classifiable to C51-C63 names C51-C63, which includes this code

Excludes2 1

These codes carry an Excludes2 note naming C63.00: its condition is not part of those codes, and both may be reported when the patient has both.

  • C43 Malignant melanoma of skin
    malignant melanoma of skin of genital organs (C51-C52, C60.-, C63.-) names C63.-, which includes this code

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR NEO042
Male reproductive system cancers - all other types
Default principal diagnosis: inpatient Yes · outpatient Yes

Clinical InformationClinical

  • Malignant Epididymal Neoplasm

    a primary or metastatic malignant neoplasm that affects the epididymis. representative examples include primary epididymal adenocarcinoma and metastatic carcinoma to the epididymis arising from another anatomic site.

Table of NeoplasmsClinical

Anatomical sites in the Table of Neoplasms that reference this code family.

SiteMalig.
Primary		Malig.
Secondary		Ca
in situ		BenignUncertainUnspec.
epididymisC63.0C79.82D07.69D29.3D40.8D49.59

Patient EducationClinical

Testicular Cancer

Testicular cancer is a cancer that develops in the tissues of one or both testicles. The testicles, or testes, are part of the male reproductive system. They make male hormones and sperm. They are two egg-shaped glands inside the scrotum, a sac of loose skin that lies below the penis. You can get cancer in one or both testicles.

The full article covers:

  • What is testicular cancer?
  • Who is most likely to develop testicular cancer?
  • What are the symptoms of testicular cancer?
  • How is testicular cancer diagnosed?
  • What are the treatments for testicular cancer?

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Convert C63.00 to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
187.5 Malig neo epididymis
Approximate The match is approximate rather than exact.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2026No changes
FY 2027CurrentCurrent code set, no changesEffective October 1, 2026 through September 30, 2027.

Questions About C63.00Overview

What is the ICD-10 code for malignant neoplasm of unspecified epididymis?

The ICD-10-CM code for malignant neoplasm of unspecified epididymis is C63.00 (sometimes written as C6300). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

Is C63.00 (Malignant neoplasm of epididymis) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report malignant neoplasm of unspecified epididymis on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

What MS-DRG does C63.00 group to?

When malignant neoplasm of unspecified epididymis is the principal diagnosis on an inpatient stay, it groups to MS-DRG 716, 723, 724, 715, 722, with relative weights from 0.5709 to 2.2896 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of C63.00?

Under the General Equivalence Mappings, malignant neoplasm of unspecified epididymis converts to ICD-9-CM 187.5 (malig neo epididymis). The mapping is approximate, so confirm the match fits the documentation.

What HCC is C63.00?

C63.00 (malignant neoplasm of unspecified epididymis) maps to CMS-HCC Category 23 (Prostate, Breast, and Other Cancers and Tumors), commonly written as HCC 23, in the CMS-HCC V28 model used for Medicare Advantage risk adjustment in payment year 2027. It mapped to HCC 12 under the retired V24 model. It also maps in the PACE (CMS-HCC V22), ESRD (V21), and ESRD (V24) models. In the Part D prescription drug model it maps to RxHCC 22.

Does C63.00 risk-adjust for Medicare Advantage payment?

Yes. When documented and reported on a Medicare Advantage encounter, C63.00 adds a risk adjustment factor of about 0.186 to the beneficiary's RAF score for a community, non-dual, aged enrollee (published V28 weights range from 0.186 to 0.237 depending on the payment segment). A more severe related category (HCC 17, HCC 18, HCC 19, HCC 20, HCC 21, and HCC 22) supersedes it when both are reported. See the full factor table on the HCC 23 category page.