D02.21

Carcinoma in situ of right bronchus and lung

FY2027Chapter 2: Neoplasms/D00–D09 In situ neoplasms

BillableComplete code, valid to report

D02.21 (also written D0221) is a billable ICD-10-CM diagnosis code for carcinoma in situ of right bronchus and lung. It is part of the FY2027 code set, effective October 1, 2026. It is one of the 7 codes in category D02 (Carcinoma in situ of middle ear and respiratory system). Its coding notes include a Use additional code instruction and 1 Excludes1 entry.

Use additional code

Add the listed code as a secondary code, if known.

Inherited from D02 Carcinoma in situ of middle ear and respiratory system
  • code to identify:
    • exposure to environmental tobacco smoke (Z77.22)
    • exposure to tobacco smoke in the perinatal period (P96.81)
    • history of tobacco dependence (Z87.891)
    • occupational exposure to environmental tobacco smoke (Z57.31)
    • tobacco dependence (F17.-)
    • tobacco use (Z72.0)

Excludes1

Not coded here. The listed conditions generally should not be reported together.

Inherited from D02 Carcinoma in situ of middle ear and respiratory system

Care settings

How CMS programs treat this code. These are CMS claim edits and list entries, not coverage or eligibility rules.

Home Health Primary

Accepted as the primary (principal) diagnosis on a home health claim. The Home Health Grouper assigns it to the MMTA - Infectious Disease, Neoplasms, and Blood-Forming Diseases clinical group.

Source: CMS Home Health Grouper Software v07.2.26, effective October 1, 2026

IPF Comorbidity

On the CMS IPF comorbidity list.

Comorbidity categoryFactor
Oncology Treatment1.44
It counts as a comorbidity when reported as a secondary diagnosis and actively treated during the stay. An IPF receives only one adjustment within a category and can receive adjustments in more than one category.

Source: CMS IPF PPS FY 2027 final rule (CMS-1847-F), Addendum B-3 (comorbidity codes with adjustment factor); effective for discharges on or after October 1, 2026

Includes

Further defines or gives examples of the content of the category.

Also from chapter/block level (4 notes)
Inherited from D00–D09 In situ neoplasms
  • Bowen's disease
  • erythroplasia
  • grade III intraepithelial neoplasia
  • Queyrat's erythroplasia

Notes

Also from chapter/block level (8 notes)
Inherited from Chapter 2 Neoplasms
  • Functional activity
  • All neoplasms are classified in this chapter, whether they are functionally active or not. An additional code from Chapter 4 may be used, to identify functional activity associated with any neoplasm.
  • Morphology [Histology]
  • Chapter 2 classifies neoplasms primarily by site (topography), with broad groupings for behavior, malignant, in situ, benign, etc. The Table of Neoplasms should be used to identify the correct topography code. In a few cases, such as for malignant melanoma and certain neuroendocrine tumors, the morphology (histologic type) is included in the category and codes.
  • Primary malignant neoplasms overlapping site boundaries
  • A primary malignant neoplasm that overlaps two or more contiguous (next to each other) sites should be classified to the subcategory/code .8 ('overlapping lesion'), unless the combination is specifically indexed elsewhere. For multiple neoplasms of the same site that are not contiguous, such as tumors in different quadrants of the same breast, codes for each site should be assigned.
  • Malignant neoplasm of ectopic tissue
  • Malignant neoplasms of ectopic tissue are to be coded to the site mentioned, e.g., ectopic pancreatic malignant neoplasms are coded to pancreas, unspecified (C25.9).