2027 ICD-10-CM Diagnosis Code C38.4Malignant neoplasm of pleura
ICD-10-CM Codes›C00–D49›C30-C39›C38
- Billable — Valid for Submission
- CC — Complication or Comorbidity
- Risk Adjusts — HCC 20
- Chronic Condition
C38.4 is a billable ICD-10-CM diagnosis code for malignant neoplasm of pleura. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 180 through 182. 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 18 closely related codes. Coders also document this condition as malignant neoplasm of parietal pleura. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Respiratory cancers.
For Medicare Advantage risk adjustment, C38.4 maps to CMS-HCC Category 20 (Lung and Other Severe Cancers) under the V28 model, adding a risk factor of about 1.136 for a community, non-dual, aged beneficiary in payment year 2027.
Code Identity
Code Classification
Medicare Risk Adjustment (HCC)Billing
C38.4 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.
- Malignant neoplasm of parietal pleura
- Malignant neoplasm of pleura
- Malignant neoplasm of visceral pleura
- Neoplasm of parietal pleura
- Neoplasm of visceral pleura
- Primary malignant germ cell neoplasm of pleura
- Primary malignant neoplasm of parietal pleura
- Primary malignant neoplasm of pleura
- Primary malignant neoplasm of visceral pleura
Instructional NotesGuidance
Instructions from the official ICD-10-CM Tabular List that apply to C38.4: its own notes plus those printed at C38, block C30-C39, and Chapter 2. A note printed at a category, block or chapter applies to every code under it.
Includes
Further defines, or gives examples of, the content of the category.
- malignant neoplasm of middle ear
Excludes1
Not coded here: the excluded code is never reported together with this one, unless the two conditions are unrelated.
- mesothelioma (C45.-)
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 C38.4, its category, or a range that includes it.
Applicable To 1
These notes mention C38.4.
- Z80.2 Family history of malignant neoplasm of other respiratory and intrathoracic organs
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Clinical InformationClinical
Malignant Pleural Neoplasm
a primary or metastatic malignant neoplasm affecting the pleura. a representative example of primary malignant pleural neoplasm is the malignant pleural mesothelioma. a representative example of metastatic malignant neoplasm to the pleura is metastatic carcinoma that has spread to the pleura from another anatomic site.
Table of NeoplasmsClinical
Anatomical sites in the Table of Neoplasms that reference this code family.
Patient EducationClinical
Cancer
Cancer is not just one disease but many diseases. Cancer begins in your cells, which are the building blocks of your body. Usually, your body forms new cells as needed, replacing old cells that die. Sometimes this process goes wrong. New cells grow even when you don't need them, and old cells don't die when they should.
The full article covers:
- What is cancer?
- What are the types of cancer?
- How does cancer develop?
- What are the symptoms of cancer?
- How is cancer diagnosed?
- What are the treatments for cancer?
- Can cancer be prevented?
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Convert C38.4 to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About C38.4Overview
What is the ICD-10 code for malignant neoplasm of pleura?
The ICD-10-CM code for malignant neoplasm of pleura is C38.4 (sometimes written as C384). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
Is C38.4 (Malignant neoplasm of heart, mediastinum and pleura) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report malignant neoplasm of pleura on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
What MS-DRG does C38.4 group to?
When malignant neoplasm of pleura is the principal diagnosis on an inpatient stay, it groups to MS-DRG 181, 180, 182, with relative weights from 0.7436 to 1.7800 depending on complications. Higher weights mean higher Medicare reimbursement.
Is C38.4 a CC or MCC?
CMS lists C38.4 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 18 closely related codes in its exclusion list.
Can C38.4 be reported with a code from C45?
Not as a rule. The Excludes1 note at C38, which applies to C38.4, lists "mesothelioma (C45.-)". 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 C38.4?
C38.4 (malignant neoplasm of pleura) maps to CMS-HCC Category 20 (Lung and Other Severe Cancers), commonly written as HCC 20, 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 20.
Does C38.4 risk-adjust for Medicare Advantage payment?
Yes. When documented and reported on a Medicare Advantage encounter, C38.4 adds a risk adjustment factor of about 1.136 to the beneficiary's RAF score for a community, non-dual, aged enrollee (published V28 weights range from 0.672 to 1.214 depending on the payment segment). A more severe related category (HCC 17, HCC 18, and HCC 19) supersedes it when both are reported. See the full factor table on the HCC 20 category page.
