C96.5 Multifocal and unisystemic Langerhans-cell histiocytosis

The ICD-10-CM code for Multifocal and unisystemic Langerhans-cell histiocytosis is C96.5 (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 C96.5:

• Schüller-Christian disease or syndrome
• Hand-Schüller-Christian disease or syndrome
• Xanthoma (s), xanthomatosis (primary) (familial) (hereditary) › bone (generalisata)
• Syndrome › Schüller-Christian
• Histiocytosis › X NEC › multifocal
• Histiocytosis › Langerhans' cell NEC › multifocal X › unisystemic

Inclusion Terms

• Hand-Schüller-Christian disease
• Histiocytosis X, multifocal

U.S. Hospital Utilization

• An estimated 55 U.S. inpatient stays in 2020 included C96.5 among the documented diagnoses.

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)