ICD-10 Code C44.599 – Other specified malignant neoplasm of skin of other part of trunk (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code C44.599 – Other specified malignant neoplasm of skin of other part of trunk
What it is
This code identifies a malignant skin tumor on the trunk that does not fit a more specific skin cancer category. Use it when the documentation names an “other specified” malignant neoplasm of trunk skin.
Clinical signs
Clinical features vary; refer to documentation. Skin cancers on the trunk may present as a changing lesion, nonhealing sore, or abnormal growth, but you should code from the documented diagnosis.
When to use this code
Use C44.599 when the provider documents a malignant neoplasm of skin on the trunk and specifies that it is “other specified” rather than basal cell, squamous cell, melanoma, or another named type. It also fits when the site is clearly on the trunk but no more specific skin cancer code is supported by the record. Check documentation if the exact histology is unclear.
Do not use for
Do not use this code for melanoma, basal cell carcinoma, squamous cell carcinoma, or benign skin lesions. Also avoid it if the lesion is on a different body site.
Coding tip
Confirm both the malignant nature and the trunk location in the pathology or provider note before assigning C44.599.