ICD-10 Code C26.1 – Malignant neoplasm of spleen (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code C26.1 – Malignant neoplasm of spleen
What it is
C26.1 identifies a malignant neoplasm involving the spleen. Use it when the record documents a primary cancer of the spleen or a malignant tumor specifically assigned to that site.
Clinical signs
Clinical features vary; refer to documentation. Commonly reported findings may include splenic enlargement, left upper quadrant discomfort, or imaging evidence of a splenic mass, but the diagnosis should be confirmed in the chart.
When to use this code
Use this code when the provider documents malignant neoplasm of the spleen as the diagnosis or confirms a primary splenic cancer. It may also apply when pathology, imaging, or oncology notes clearly identify the spleen as the involved site. Check documentation if the record instead describes metastatic disease or an unspecified abdominal malignancy.
Do not use for
Do not use C26.1 for benign splenic lesions, lymphoma unless documented as a splenic malignancy in this code set, or metastatic cancer to the spleen without explicit coding guidance. Check documentation.
Coding tip
Verify whether the spleen is the primary site, secondary site, or only suspected site before assigning C26.1.