ICD-10-CM 2027 diagnosis code
QA1.791Familial cancer syndrome with pathogenic BRCA2 mutation
QA1.791 is a valid, billable ICD-10-CM code for familial cancer syndrome with pathogenic brca2 mutation. It can be reported on claims for dates of service from October 1, 2026 – September 30, 2027.
Code last changed in FY2027 (effective October 1, 2026). Source: official FY2027 ICD-10-CM release from CDC/NCHS and CMS. Page updated September 29, 2026. About our data
About QA1.791
QA1.791 is the ICD-10-CM diagnosis code for familial cancer syndrome with pathogenic BRCA2 mutation. It belongs to category QA1 (genetic disorders associated with neoplasms, not elsewhere classified), block QA0-QA1 (genetic disorders, not elsewhere classified) and chapter 17 (congenital malformations, deformations, chromosomal abnormalities, and genetic disorders). It is billable, so it can be reported on its own for dates of service from October 1, 2026 through September 30, 2027.
Within QA1.79 (other inherited neoplasm predisposition syndrome of multiple systems), QA1.791 is specifically for familial cancer syndrome with pathogenic BRCA2 mutation. Related codes cover familial cancer syndrome with pathogenic BRCA1 mutation (QA1.790), Li Fraumeni syndrome (QA1.792) and other inherited neoplasm predisposition syndrome of multiple systems (QA1.798).
It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.
In MS-DRG v44.0, it is part of the grouping logic for DRG 951 (Other Factors Influencing Health Status, relative weight 0.5577), in MDC 23 (Factors Influencing Health Status and Other Contacts with Health Services), 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 is exempt from present-on-admission (POA) reporting, so no POA indicator is required.
It was added in FY2027, effective October 1, 2026.
Coding notes
- BRCA2-cancer predisposition syndrome
- Hereditary breast and ovarian cancer syndrome with pathogenic BRCA2 mutation
Notes that apply from higher levels
Instructions written at a parent level also apply to QA1.791.
Broader instructions also apply from Chapter 17: Congenital malformations, deformations, chromosomal abnormalities, and genetic disorders.
Alphabetic index entries
3 entriesTerms in the official ICD-10-CM index that lead to QA1.791.
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.
MDC 23 · Factors Influencing Health Status and Other Contacts with Health Services
Code history
- 2016
- 2017
- 2018
- 2019
- 2020
- 2021
- 2022
- 2023
- 2024
- 2025
- 2026
- 2027
- FY2027 (effective 10/1/2026): Added
Common questions about QA1.791
Is QA1.791 billable?
- Yes. QA1.791 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can QA1.791 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict QA1.791 as a principal diagnosis.
Is QA1.791 a CC or MCC?
- No. QA1.791 is neither a CC nor an MCC under MS-DRG v44.0.
What DRG does QA1.791 group to?
- QA1.791 is used in the MS-DRG v44.0 logic for MS-DRG 951 (Other Factors Influencing Health Status). Which one applies depends on whether it is the principal diagnosis and on the rest of the claim.
Did QA1.791 change for 2027?
- Yes. For FY2027 (effective October 1, 2026) it was added to the code set.