2027 ICD-10-CM Diagnosis Code N42.32Atypical small acinar proliferation of prostate

ICD-10-CM Codes›N00–N99›N40-N53›N42

ICD-10-CM N42.32
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

N42.32 is a billable ICD-10-CM diagnosis code for atypical small acinar proliferation of prostate. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 729 through 730. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Other specified male genital disorders.

Code Identity

ICD-10-CM Code
N42.32
Billable Status
Yes — Valid for Submission
Code Describes
Atypical small acinar proliferation of prostate
Short Description
Atypical small acinar proliferation of prostate
Same as the full description in the CMS dataset.
Parent Code
N42.3
Dysplasia of prostate

Code Classification

ChapterN00–N99Diseases of the genitourinary system
SectionN40-N53Diseases of male genital organs
CategoryN42Other and unspecified disorders of prostate
This CodeN42.32Atypical small acinar proliferation of prostate

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Atypical small acinar proliferation of prostate

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to N42.32: its own notes plus those printed at Chapter 14. A note printed at a category, block or chapter applies to every code under it.

Excludes2

Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.

From Chapter 14 (N00-N99) Diseases of the genitourinary system applies to 838 codes
  • certain conditions originating in the perinatal period (P04-P96)
  • certain infectious and parasitic diseases (A00-B99)
  • complications of pregnancy, childbirth and the puerperium (O00-O9A)
  • congenital malformations, deformations and chromosomal abnormalities (Q00-Q99)
  • endocrine, nutritional and metabolic diseases (E00-E88)
  • injury, poisoning and certain other consequences of external causes (S00-T88)
  • neoplasms (C00-D49)
  • symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)

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

Referenced in Other NotesGuidance

Instructional notes printed at other codes that name N42.32, its category, or a range that includes it.

Excludes1 2

These codes carry an Excludes1 note naming N42.32: they are not reported together with it, unless the two conditions are unrelated.

  • D07.5 Carcinoma in situ of prostate
    dysplasia (mild) (moderate) of prostate (N42.3-) names N42.3-, which includes this code
  • D07.5 Carcinoma in situ of prostate
    prostatic intraepithelial neoplasia II [PIN II] (N42.3-) names N42.3-, which includes this code

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

Clinical ClassificationClinical

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

CCSR GEN016
Other specified male genital disorders
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Prostate Diseases

The prostate is a gland in the male reproductive system. It lies just below the bladder. It makes fluid that is part of semen.

The full article covers:

  • What is the prostate?
  • What are prostate diseases?
  • Who is more likely to develop prostate diseases?
  • What are the symptoms of prostate diseases?
  • How are prostate diseases diagnosed?

Read the full article at MedlinePlus

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

Convert N42.32 to ICD-9-CMHistory

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

ICD-9-CM
602.3 Dysplasia of prostate
Approximate The match is approximate rather than exact.

Code History & ChangesHistory

Replacement N42.32 replaces the following previously assigned code(s):

  • N42.3 - Dysplasia of prostate
FY 2019AddedAdded to the ICD-10-CM code setEffective October 1, 2018.
FY 2020–2026No changes
FY 2027CurrentCurrent code set, no changesEffective October 1, 2026 through September 30, 2027.

Questions About N42.32Overview

What is the ICD-10 code for atypical small acinar proliferation of prostate?

The ICD-10-CM code for atypical small acinar proliferation of prostate is N42.32 (sometimes written as N4232). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

Is N42.32 (Dysplasia of prostate) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report atypical small acinar proliferation of prostate on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

What MS-DRG does N42.32 group to?

When atypical small acinar proliferation of prostate is the principal diagnosis on an inpatient stay, it groups to MS-DRG 729, 730, with relative weights from 0.6595 to 1.0553 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of N42.32?

Under the General Equivalence Mappings, atypical small acinar proliferation of prostate converts to ICD-9-CM 602.3 (dysplasia of prostate). The mapping is approximate, so confirm the match fits the documentation.