2026 ICD-10-CM Diagnosis Code M36.0Dermato(poly)myositis in neoplastic disease
ICD-10-CM Codes›M00–M99›M30-M36›M36
- Billable — Valid for Submission
- CC — Complication or Comorbidity
- Risk Adjusts — HCC 93
- Chronic Condition
M36.0 is a billable ICD-10-CM diagnosis code for dermato(poly)myositis in neoplastic disease. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 545 through 547. 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 15 closely related codes. The code is a manifestation code that cannot be reported as the principal diagnosis. Coders also document this condition as dermatomyositis with malignant disease. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Conditions due to neoplasm or the treatment of neoplasm and Systemic lupus erythematosus and connective tissue disorders.
For Medicare Advantage risk adjustment, M36.0 maps to CMS-HCC Category 93 (Rheumatoid Arthritis and Other Specified Inflammatory Rheumatic Disorders) under the V28 model, adding a risk factor of about 0.617 for a community, non-dual, aged beneficiary in payment year 2026.
Code Identity
Code Classification
Code EditsBilling
Medicare Code Editor checks that affect claim validity for M36.0.
Medicare Risk Adjustment (HCC)Billing
M36.0 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 2026.
Source: CMS Payment Year 2026 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.
- Dermatomyositis with malignant disease
- Juvenile polymyositis
- Juvenile polymyositis due to paraneoplastic syndrome
- Myopathy due to paraneoplastic syndrome
- Polymyositis
Tabular List NotesGuidance
Coding notes and annotation back-references applicable to this code.
Code First
Certain conditions have both an underlying etiology and multiple body system manifestations due to the underlying etiology. For such conditions, the ICD-10-CM has a coding convention that requires the underlying condition be sequenced first followed by the manifestation. Wherever such a combination exists, there is a "use additional code" note at the etiology code, and a "code first" note at the manifestation code. These instructional notes indicate the proper sequencing order of the codes, etiology followed by manifestation.
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Clinical InformationClinical
Dermatomyositis
a subacute or chronic inflammatory disease of muscle and skin, marked by proximal muscle weakness and a characteristic skin rash. the illness occurs with approximately equal frequency in children and adults. the skin lesions usually take the form of a purplish rash (or less often an exfoliative dermatitis) involving the nose, cheeks, forehead, upper trunk, and arms. the disease is associated with a complement mediated intramuscular microangiopathy, leading to loss of capillaries, muscle ischemia, muscle-fiber necrosis, and perifascicular atrophy. the childhood form of this disease tends to evolve into a systemic vasculitis. dermatomyositis may occur in association with malignant neoplasms. (from adams et al., principles of neurology, 6th ed, pp1405-6)Polymyositis
diseases characterized by inflammation involving multiple muscles. this may occur as an acute or chronic condition associated with medication toxicity (drug toxicity); connective tissue diseases; infections; malignant neoplasms; and other disorders. the term polymyositis is frequently used to refer to a specific clinical entity characterized by subacute or slowly progressing symmetrical weakness primarily affecting the proximal limb and trunk muscles. the illness may occur at any age, but is most frequent in the fourth to sixth decade of life. weakness of pharyngeal and laryngeal muscles, interstitial lung disease, and inflammation of the myocardium may also occur. muscle biopsy reveals widespread destruction of segments of muscle fibers and an inflammatory cellular response. (adams et al., principles of neurology, 6th ed, pp1404-9)
Patient EducationClinical
Myositis
Myositis means inflammation of the muscles that you use to move your body. An injury, infection, or autoimmune disease can cause it. Two specific kinds are polymyositis and dermatomyositis. Polymyositis causes muscle weakness, usually in the muscles closest to the trunk of your body.
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Convert M36.0 to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About M36.0Overview
What is the ICD-10 code for dermato(poly)myositis in neoplastic disease?
The ICD-10-CM code for dermato(poly)myositis in neoplastic disease is M36.0 (sometimes written as M360). It is billable on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
Is M36.0 a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report dermato(poly)myositis in neoplastic disease on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What MS-DRG does M36.0 group to?
On inpatient claims, dermato(poly)myositis in neoplastic disease maps to MS-DRG 545, 546, 547, with relative weights from 0.8362 to 2.4817 depending on complications. Higher weights mean higher Medicare reimbursement.
Is M36.0 a CC or MCC?
CMS lists M36.0 as a CC (complication or comorbidity) for FY 2026. 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 15 closely related codes in its exclusion list.
Can M36.0 be a principal diagnosis?
No. This is a manifestation code: dermato(poly)myositis in neoplastic disease describes the manifestation of an underlying disease rather than the disease itself, so the underlying condition is sequenced first.
What HCC is M36.0?
M36.0 (dermato(poly)myositis in neoplastic disease) maps to CMS-HCC Category 93 (Rheumatoid Arthritis and Other Specified Inflammatory Rheumatic Disorders), commonly written as HCC 93, in the CMS-HCC V28 model used for Medicare Advantage risk adjustment in payment year 2026. It mapped to HCC 40 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 83.
Does M36.0 risk-adjust for Medicare Advantage payment?
Yes. When documented and reported on a Medicare Advantage encounter, M36.0 adds a risk adjustment factor of about 0.617 to the beneficiary's RAF score for a community, non-dual, aged enrollee (published V28 weights range from 0.288 to 0.617 depending on the payment segment). HCC 93 sits at the top of its hierarchy, so no other condition category supersedes it. See the full factor table on the HCC 93 category page.
