2027 ICD-10-CM Diagnosis Code C90.20Extramedullary plasmacytoma not having achieved remission
ICD-10-CM Codes›C00–D49›C81-C96›C90
- Billable — Valid for Submission
- CC — Complication or Comorbidity
- Risk Adjusts — HCC 19
- Chronic Condition
C90.20 is a billable ICD-10-CM diagnosis code for extramedullary plasmacytoma not having achieved remission. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 820 through 825, 840 through 842. As a secondary diagnosis, it counts as a complication or comorbidity (CC) and moves an inpatient stay to a higher severity level within its MS-DRG family. It does not count, however, when the principal diagnosis is one of 113 closely related codes. Coders also document this condition as extramedullary plasmacytoma. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Multiple myeloma.
For Medicare Advantage risk adjustment, C90.20 maps to CMS-HCC Category 19 (Myelodysplastic Syndromes, Multiple Myeloma, and Other Cancers) under the V28 model, adding a risk factor of about 1.798 for a community, non-dual, aged beneficiary in payment year 2027.
Code Identity
Code Classification
Medicare Risk Adjustment (HCC)Billing
C90.20 maps to a payment category in the CMS-HCC model used to risk-adjust Medicare Advantage payments. Weights are the published community factors for payment year 2027.
Source: CMS Payment Year 2027 risk adjustment mappings and model software. Weights are relative factors, not dollar amounts; a beneficiary's total RAF also includes demographics and interactions. Browse all CMS-HCC categories.
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Extramedullary plasmacytoma
- Plasmacytoma
- Primary cutaneous plasmacytoma
Instructional NotesGuidance
Instructions from the official ICD-10-CM Tabular List that apply to C90.20: its own notes plus those printed at C90, block C81-C96, and Chapter 2. A note printed at a category, block or chapter applies to every code under it.
Applicable To
Conditions this code is used for: synonyms of the title or, for "other specified" codes, the conditions assigned to it. The list is not exhaustive.
- Extramedullary plasmacytoma with failed remission
- Extramedullary plasmacytoma NOS
Excludes1
Not coded here: the excluded code is never reported together with this one, unless the two conditions are unrelated.
Excludes2
Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.
Notes
General instructions on how these codes are used.
- 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).
Source: CMS ICD-10-CM Tabular List. How to read instructional notes.
Referenced in Other NotesGuidance
Instructional notes printed at other codes that name C90.20, its category, or a range that includes it.
Applicable To 1
These notes mention C90.20.
- Z85.79 Personal history of other malignant neoplasms of lymphoid, hematopoietic and related tissues
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Clinical InformationClinical
Extraosseous Plasmacytoma
a localized malignant neoplasm arising in an extraosseous site. it is composed of clonal (malignant) plasma cells forming a tumor mass. it most frequently involves the oropharynx, nasopharynx, sinuses, and larynx.
Patient EducationClinical
Multiple Myeloma
Multiple myeloma is a cancer that begins in plasma cells, a type of white blood cell. These cells are part of your immune system, which helps protect the body from germs and other harmful substances. In time, myeloma cells collect in the bone marrow and in the solid parts of bones.
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Convert C90.20 to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About C90.20Overview
What is the ICD-10 code for extramedullary plasmacytoma not having achieved remission?
The ICD-10-CM code for extramedullary plasmacytoma not having achieved remission is C90.20 (sometimes written as C9020). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
Is C90.20 (Extramedullary plasmacytoma) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report extramedullary plasmacytoma not having achieved remission on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
What MS-DRG does C90.20 group to?
When extramedullary plasmacytoma not having achieved remission is the principal diagnosis on an inpatient stay, it groups to MS-DRG 841, 821, 822, 825, 842, 824, 840, 820, 823, with relative weights from 0.9948 to 6.2454 depending on complications. Higher weights mean higher Medicare reimbursement.
Is C90.20 a CC or MCC?
CMS lists C90.20 as a CC (complication or comorbidity) for FY 2027. Reported as a secondary diagnosis, it moves the inpatient stay to a higher-weighted DRG within its severity family. It does not count when the principal diagnosis is one of the 113 closely related codes in its exclusion list.
Can C90.20 be reported with Z85.79?
Not as a rule. The Excludes1 note at C90, which applies to C90.20, lists "personal history of other malignant neoplasms of lymphoid, hematopoietic and related tissues (Z85.79)". An Excludes1 note means the excluded code is never reported together with this one; the only exception is when the two conditions are unrelated to each other (Official Guidelines, Section I.A.12.a).
What HCC is C90.20?
C90.20 (extramedullary plasmacytoma not having achieved remission) maps to CMS-HCC Category 19 (Myelodysplastic Syndromes, Multiple Myeloma, and Other Cancers), commonly written as HCC 19, in the CMS-HCC V28 model used for Medicare Advantage risk adjustment in payment year 2027. It mapped to HCC 9 under the retired V24 model. It also maps in the PACE (CMS-HCC V22), ESRD (V21), and ESRD (V24) models. In the Part D prescription drug model it maps to RxHCC 16.
Does C90.20 risk-adjust for Medicare Advantage payment?
Yes. When documented and reported on a Medicare Advantage encounter, C90.20 adds a risk adjustment factor of about 1.798 to the beneficiary's RAF score for a community, non-dual, aged enrollee (published V28 weights range from 0.957 to 1.989 depending on the payment segment). A more severe related category (HCC 17 and HCC 18) supersedes it when both are reported. See the full factor table on the HCC 19 category page.
