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ICD-10-CM 2027 diagnosis code

C85.21Mediastinal (thymic) large B-cell lymphoma, lymph nodes of head, face, and neck

✓ Billable / specificCC — complication/comorbidity

C85.21 is a valid, billable ICD-10-CM code for mediastinal (thymic) large b-cell lymphoma, lymph nodes of head, face, and neck. It can be reported on claims for dates of service from October 1, 2026 – September 30, 2027.Short description: Mediastnl large B-cell lymph, nodes of head, face, and neck

Code unchanged since ICD-10-CM took effect on October 1, 2015. Source: official FY2027 ICD-10-CM release from CDC/NCHS and CMS. Page updated September 29, 2026. About our data

About C85.21

C85.21 is the ICD-10-CM diagnosis code for mediastinal (thymic) large B-cell lymphoma, lymph nodes of head, face, and neck. It belongs to category C85 (other specified and unspecified types of non-Hodgkin lymphoma), block C81-C96 (malignant neoplasms of lymphoid, hematopoietic and related tissue) and chapter 2 (neoplasms). It is billable, so it can be reported on its own for dates of service from October 1, 2026 through September 30, 2027.

Within C85.2 (mediastinal (thymic) large B-cell lymphoma), C85.21 is specifically for mediastinal (thymic) large B-cell lymphoma, lymph nodes of head, face, and neck. Related codes cover unspecified site (C85.20), intrathoracic lymph nodes (C85.22), intra-abdominal lymph nodes (C85.23), lymph nodes of axilla and upper limb (C85.24), lymph nodes of inguinal region and lower limb (C85.25), intrapelvic lymph nodes (C85.26), spleen (C85.27), lymph nodes of multiple sites (C85.28) and 2 more.

As a secondary diagnosis it is a CC (complication or comorbidity), which can move an inpatient stay into the "with CC" MS-DRG of its family, unless the principal diagnosis excludes it.

In MS-DRG v44.0, it is part of the grouping logic for DRG 011 (Tracheostomy for Face, Mouth and Neck Diagnoses or Laryngectomy with MCC, relative weight 5.6154), DRG 012 (Tracheostomy for Face, Mouth and Neck Diagnoses or Laryngectomy with CC, relative weight 4.381), DRG 013 (Tracheostomy for Face, Mouth and Neck Diagnoses or Laryngectomy without CC/MCC, relative weight 2.7307), DRG 820 (Lymphoma and Leukemia with Major O.R. Procedures with MCC, relative weight 6.2481), DRG 821 (Lymphoma and Leukemia with Major O.R. Procedures with CC, relative weight 2.2023), DRG 822 (Lymphoma and Leukemia with Major O.R. Procedures without CC/MCC, relative weight 1.1272) and 9 more, in Pre-MDC, MDC 17 (Myeloproliferative Diseases and Disorders, Poorly Differentiated Neoplasms) and MDC 25 (Human Immunodeficiency Virus Infections), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.

It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.

Before ICD-10, this condition was coded in ICD-9-CM as 200.71 (large cell lymphoma, lymph nodes of head, face, and neck) and 202.81 (other malignant lymphomas, lymph nodes of head, face, and neck).

Notes that apply from higher levels

Instructions written at a parent level also apply to C85.21.

› From C85 Other specified and unspecified types of non-Hodgkin lymphoma
Excludes1
  • other specified types of T/NK-cell lymphoma (C86.-)
  • personal history of non-Hodgkin lymphoma (Z85.72)

Broader instructions also apply from C81-C96 Malignant neoplasms of lymphoid, hematopoietic and related tissue and Chapter 2: Neoplasms.

MS-DRG v44.0 grouping

All DRGs →

Inpatient MS-DRGs this diagnosis can group to, as the principal or a secondary diagnosis, depending on the rest of the claim.

ICD-9-CM equivalent

Converter →
  • 200.71Large cell lymphoma, lymph nodes of head, face, and neckapproximate
  • 202.81Other malignant lymphomas, lymph nodes of head, face, and neckapproximate

From the CMS 2018 General Equivalence Mappings (GEMs), the final GEMs release.

Code history

  1. 2016
  2. 2017
  3. 2018
  4. 2019
  5. 2020
  6. 2021
  7. 2022
  8. 2023
  9. 2024
  10. 2025
  11. 2026
  12. 2027
  • FY2016 (effective 10/1/2015): Added (first year of ICD-10-CM)
  • No changes since FY2016.

Common questions about C85.21

Is C85.21 billable?

Yes. C85.21 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).

Can C85.21 be used as a principal diagnosis?

Yes. The Medicare Code Editor doesn't restrict C85.21 as a principal diagnosis.

Is C85.21 a CC or MCC?

C85.21 is a CC (complication or comorbidity) under MS-DRG v44.0, unless excluded by the principal diagnosis.

What DRG does C85.21 group to?

C85.21 is used in the MS-DRG v44.0 logic for MS-DRG 011 (Tracheostomy for Face, Mouth and Neck Diagnoses or Laryngectomy with MCC), MS-DRG 012 (Tracheostomy for Face, Mouth and Neck Diagnoses or Laryngectomy with CC), MS-DRG 013 (Tracheostomy for Face, Mouth and Neck Diagnoses or Laryngectomy without CC/MCC), MS-DRG 820 (Lymphoma and Leukemia with Major O.R. Procedures with MCC), MS-DRG 821 (Lymphoma and Leukemia with Major O.R. Procedures with CC), MS-DRG 822 (Lymphoma and Leukemia with Major O.R. Procedures without CC/MCC) and 9 more. Which one applies depends on whether it is the principal diagnosis and on the rest of the claim.

What is the ICD-9 code for C85.21?

The CMS General Equivalence Mappings map C85.21 to ICD-9-CM 200.71 and 202.81.