J91.0 Malignant pleural effusion

Billable ICD-10-CM code, FY2026. Acts as a Complication or Comorbidity (CC) as a secondary diagnosis.

Code first

• underlying neoplasm (C00-D49)

Applies from J91 Pleural effusion in conditions classified elsewhere

Excludes2 (not included here)

• pleural effusion in heart failure (I50.-)
• pleural effusion in systemic lupus erythematosus (M32.13)

Risk adjustment (HCC)

• CMS-HCC V28: HCC 17 — Cancer Metastatic to Lung, Liver, Brain, and Other Organs; Acute Myeloid Leukemia Except Promyelocytic

MS-DRG index

Defines the logic of DRG(s) 180-182 in MDC 04.

Approximate ICD-9-CM (GEMs)

• 511.81 Malignant pleural effusion

Medicare Code Edits (MCE v43.1 (April 2026))

• Manifestation codes as principal diagnosis: Manifestation codes describe the manifestation of an underlying disease, not the disease itself, and are not allowed as principal diagnosis.

Code annotations containing back-references to J91.0

Back-references to J91.0

• Type 1 Excludes: J90 Pleural effusion, not elsewhere classified ("malignant pleural effusion (J91.0))")

Diagnosis Index entries for J91.0

• Effusion › malignant pleural
• Effusion › pleura, pleurisy, pleuritic, pleuropericardial › malignant

Nearby codes

• J91 Pleural effusion in conditions classified elsewhere
• J91.0 Malignant pleural effusion (this code)
• J91.8 Pleural effusion in other conditions classified elsewhere