MS-DRG v44.0 · MDC 09: Diseases and Disorders of the Skin, Subcutaneous Tissue and Breast
597 — Malignant Breast Disorders with MCC
Source: CMS MS-DRG v44.0 and FY2027 IPPS final rule. Page updated September 29, 2026.
- Relative weight
- 1.7383
- Geometric mean LOS
- 4.8 days
- Arithmetic mean LOS
- 6.6 days
- Type
- Medical
About MS-DRG 597
MS-DRG 597, Malignant Breast Disorders with MCC, is a medical DRG in MDC 09 (Diseases and Disorders of the Skin, Subcutaneous Tissue and Breast) under MS-DRG version 44.0, which applies to inpatient discharges from October 1, 2026 through September 30, 2027.
Its FY2027 relative weight is 1.7383, so Medicare's base payment for this DRG is about 1.74 times the average inpatient case, before hospital-specific adjustments. The geometric mean length of stay is 4.8 days and the arithmetic mean is 6.6 days.
It belongs to a 3-level severity family: DRG 597 (with MCC, weight 1.7383), DRG 598 (with CC, weight 1.0962) and DRG 599 (without CC/MCC, weight 0.6925). The highest-severity level carries 2.5 times the weight of the lowest, which is why documenting CC and MCC conditions matters.
74 ICD-10-CM diagnosis codes are part of this DRG's grouping logic; they are listed below.
ICD-10-CM codes that group to DRG 597 (74)
Chapter 2: Neoplasms
- C50.011Malignant neoplasm of nipple and areola, right female breast
- C50.012Malignant neoplasm of nipple and areola, left female breast
- C50.019Malignant neoplasm of nipple and areola, unspecified female breast
- C50.021Malignant neoplasm of nipple and areola, right male breast
- C50.022Malignant neoplasm of nipple and areola, left male breast
- C50.029Malignant neoplasm of nipple and areola, unspecified male breast
- C50.111Malignant neoplasm of central portion of right female breast
- C50.112Malignant neoplasm of central portion of left female breast
- C50.119Malignant neoplasm of central portion of unspecified female breast
- C50.121Malignant neoplasm of central portion of right male breast
- C50.122Malignant neoplasm of central portion of left male breast
- C50.129Malignant neoplasm of central portion of unspecified male breast
- C50.211Malignant neoplasm of upper-inner quadrant of right female breast
- C50.212Malignant neoplasm of upper-inner quadrant of left female breast
- C50.219Malignant neoplasm of upper-inner quadrant of unspecified female breast
- C50.221Malignant neoplasm of upper-inner quadrant of right male breast
- C50.222Malignant neoplasm of upper-inner quadrant of left male breast
- C50.229Malignant neoplasm of upper-inner quadrant of unspecified male breast
- C50.311Malignant neoplasm of lower-inner quadrant of right female breast
- C50.312Malignant neoplasm of lower-inner quadrant of left female breast
- C50.319Malignant neoplasm of lower-inner quadrant of unspecified female breast
- C50.321Malignant neoplasm of lower-inner quadrant of right male breast
- C50.322Malignant neoplasm of lower-inner quadrant of left male breast
- C50.329Malignant neoplasm of lower-inner quadrant of unspecified male breast
- C50.411Malignant neoplasm of upper-outer quadrant of right female breast
- C50.412Malignant neoplasm of upper-outer quadrant of left female breast
- C50.419Malignant neoplasm of upper-outer quadrant of unspecified female breast
- C50.421Malignant neoplasm of upper-outer quadrant of right male breast
- C50.422Malignant neoplasm of upper-outer quadrant of left male breast
- C50.429Malignant neoplasm of upper-outer quadrant of unspecified male breast
- C50.511Malignant neoplasm of lower-outer quadrant of right female breast
- C50.512Malignant neoplasm of lower-outer quadrant of left female breast
- C50.519Malignant neoplasm of lower-outer quadrant of unspecified female breast
- C50.521Malignant neoplasm of lower-outer quadrant of right male breast
- C50.522Malignant neoplasm of lower-outer quadrant of left male breast
- C50.529Malignant neoplasm of lower-outer quadrant of unspecified male breast
- C50.611Malignant neoplasm of axillary tail of right female breast
- C50.612Malignant neoplasm of axillary tail of left female breast
- C50.619Malignant neoplasm of axillary tail of unspecified female breast
- C50.621Malignant neoplasm of axillary tail of right male breast
- C50.622Malignant neoplasm of axillary tail of left male breast
- C50.629Malignant neoplasm of axillary tail of unspecified male breast
- C50.811Malignant neoplasm of overlapping sites of right female breast
- C50.812Malignant neoplasm of overlapping sites of left female breast
- C50.819Malignant neoplasm of overlapping sites of unspecified female breast
- C50.821Malignant neoplasm of overlapping sites of right male breast
- C50.822Malignant neoplasm of overlapping sites of left male breast
- C50.829Malignant neoplasm of overlapping sites of unspecified male breast
- C50.911Malignant neoplasm of unspecified site of right female breast
- C50.912Malignant neoplasm of unspecified site of left female breast
- C50.919Malignant neoplasm of unspecified site of unspecified female breast
- C50.921Malignant neoplasm of unspecified site of right male breast
- C50.922Malignant neoplasm of unspecified site of left male breast
- C50.929Malignant neoplasm of unspecified site of unspecified male breast
- C50.A0Malignant inflammatory neoplasm of unspecified breast
- C50.A1Malignant inflammatory neoplasm of right breast
- C50.A2Malignant inflammatory neoplasm of left breast
- C79.2Secondary malignant neoplasm of skin
- C79.81Secondary malignant neoplasm of breast
- D05.00Lobular carcinoma in situ of unspecified breast
- D05.01Lobular carcinoma in situ of right breast
- D05.02Lobular carcinoma in situ of left breast
- D05.10Intraductal carcinoma in situ of unspecified breast
- D05.11Intraductal carcinoma in situ of right breast
- D05.12Intraductal carcinoma in situ of left breast
- D05.80Other specified type of carcinoma in situ of unspecified breast
- D05.81Other specified type of carcinoma in situ of right breast
- D05.82Other specified type of carcinoma in situ of left breast
- D05.90Unspecified type of carcinoma in situ of unspecified breast
- D05.91Unspecified type of carcinoma in situ of right breast
- D05.92Unspecified type of carcinoma in situ of left breast
- D48.60Neoplasm of uncertain behavior of unspecified breast
- D48.61Neoplasm of uncertain behavior of right breast
- D48.62Neoplasm of uncertain behavior of left breast
Common questions about DRG 597
What is the relative weight of DRG 597?
- 1.7383 for FY2027 (MS-DRG v44.0), from the IPPS final rule Table 5.
What is the average length of stay for DRG 597?
- The geometric mean length of stay is 4.8 days; the arithmetic mean is 6.6 days.
Is DRG 597 medical or surgical?
- DRG 597 is a medical DRG.