2026 ICD-10-CM Diagnosis Code E34.2Ectopic hormone secretion, not elsewhere classified

ICD-10-CM Codes›E00–E89›E20-E35›E34

ICD-10-CM E34.2
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

E34.2 is a billable ICD-10-CM diagnosis code for ectopic hormone secretion, not elsewhere classified. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 643 through 645. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Other specified and unspecified endocrine disorders.

Code Identity

ICD-10-CM Code
E34.2
Billable Status
Yes — Valid for Submission
Code Describes
Ectopic hormone secretion, not elsewhere classified
Short Description
Ectopic hormone secretion, not elsewhere classified
Same as the full description in the CMS dataset.
Parent Code
E34
Other endocrine disorders

Code Classification

ChapterE00–E89Endocrine, nutritional and metabolic diseases
SectionE20-E35Disorders of other endocrine glands
CategoryE34Other endocrine disorders
This CodeE34.2Ectopic hormone secretion, not elsewhere classified

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Aberrant parathyroid gland
  • Congenital anomaly of parathyroid glands
  • Ectopic aldosterone secretion
  • Ectopic aldosterone-producing neoplasm
  • Ectopic antidiuretic hormone secretion
  • Ectopic calcitonin production
  • Ectopic GHRH secretion causing acromegaly
  • Ectopic growth hormone secretion
  • Ectopic hyperparathyroidism
  • Ectopic parathyroid hormone-related protein secretion
  • Ectopic production of endocrine substance
  • Ectopic prolactin secretion
  • Ectopic renin secretion
  • Parathyromatosis

Tabular List NotesGuidance

Coding notes and annotation back-references applicable to this code.

Type 1 Excludes

  • ectopic ACTH syndrome E24.3

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

External Cause of Injuries IndexGuidance

References for this code in the External Cause of Injuries Index.

    • Ectopic, ectopia(congenital)
      • hormone secretion NEC
    • Secretion
      • hormone
        • ectopic NEC

Clinical ClassificationClinical

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

CCSR END015
Other specified and unspecified endocrine disorders
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Endocrine Diseases

Your endocrine system includes eight major glands throughout your body. These glands make hormones. Hormones are chemical messengers. They travel through your bloodstream to tissues or organs. Hormones work slowly and affect body processes from head to toe. These include:

Read the full article at MedlinePlus

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

Convert E34.2 to ICD-9-CMHistory

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

ICD-9-CM
259.3 Ectopic hormone secr NEC
Exact Match The mapping is direct, with no qualifiers.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About E34.2Overview

Is E34.2 (Other endocrine disorders) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report ectopic hormone secretion, not elsewhere classified on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does E34.2 group to?

When ectopic hormone secretion, not elsewhere classified is the principal diagnosis on an inpatient stay, it groups to MS-DRG 643, 644, 645, with relative weights from 0.7683 to 1.6461 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of E34.2?

Under the General Equivalence Mappings, ectopic hormone secretion, not elsewhere classified converts to ICD-9-CM 259.3 (ectopic hormone secr NEC). The mapping is a direct match.

Footnotes

[1] Chronic - a chronic condition code indicates a condition lasting 12 months or longer and its effect on the patient based on one or both of the following criteria:

  • The condition results in the need for ongoing intervention with medical products,treatment, services, and special equipment
  • The condition places limitations on self-care, independent living, and social interactions.