C96.6 Unifocal Langerhans-cell histiocytosis

The ICD-10-CM code for Unifocal Langerhans-cell histiocytosis is C96.6 (FY2026). It is a billable, claim-ready diagnosis code.

Classification

Chapter

2: Neoplasms (C00-D49)

Section

C81-C96: Malignant neoplasms of lymphoid, hematopoietic and related tissue (C81-C96)

Category C96

13 codes (11 billable)

FY2026 Status

Stable since FY2024

Also Known As

ICD-10-CM Alphabetic Index entries that lead to C96.6:

• Histiocytosis › Langerhans' cell NEC
• Granuloma › eosinophilic
• Histiocytosis › X NEC
• Granuloma › eosinophilic › lung
• Granuloma › bone › lung
• Granuloma › bone › eosinophilic
• Granuloma › lung (infectious) › eosinophilic
• Granuloma › eosinophilic › bone

Inclusion Terms

• Eosinophilic granuloma
• Histiocytosis X, unifocal
• Histiocytosis X NOS
• Langerhans-cell histiocytosis NOS

U.S. Hospital Utilization

• An estimated 1,720 U.S. inpatient stays in 2023 included C96.6 among the documented diagnoses.
• 295 stays listed it as the principal diagnosis.

Source: National Inpatient Sample (NIS), Healthcare Cost and Utilization Project (HCUP), Agency for Healthcare Research and Quality, 2016–2023. National survey-weighted estimates.

Official Coding Guidelines

Tx of primary site (TOC entry)

a. Admission/Encounter for treatment of primary site ............................................................. 33

Tx of secondary site (TOC entry)

b. Admission/Encounter for treatment of secondary site .......................................................... 33

Source: CMS — ICD-10-CM Official Guidelines for Coding and Reporting, FY2026

References

• CMS — ICD-10-CM Official Code Set and Guidelines, FY2026
• CDC/NCHS — ICD-10-CM Files and Browser Tool
• AHRQ — HCUP National Inpatient Sample, Frequencies by Diagnosis Code (2016–2023)

Cite This Page

Reference C96.6 with the canonical source and edition:

C96.6 — Unifocal Langerhans-cell histiocytosis. ICD-10 Coding Pro (ICD-10-CM FY2026). https://icd10codingpro.com/codes/C96.6

Canonical URL: https://icd10codingpro.com/codes/C96.6