Malignant neoplasm of ovrlp sites of conn and soft tissue

This code signifies a primary malignant tumor that originates in or extends across multiple contiguous anatomical regions of connective and soft tissues. This includes sarcomas or other malignant neoplasms that span boundaries of distinct soft tissue sites, making it impossible to assign to a single, more specific anatomical location.

Apply this code when medical record documentation clearly indicates a malignant neoplasm involving two or more adjacent or overlapping sites of connective or soft tissue. This is appropriate when the tumor's extent prevents classification to a single, more precise C49 subcategory (e.g., C49.0-C49.6). Documentation should explicitly state the overlapping nature or involvement of multiple sites.

• Ensure the documentation specifies "malignant" and "overlapping sites" of connective/soft tissue; do not use for benign or in situ lesions.
• Prioritize more specific C49 subcodes if the tumor can be definitively localized to a single anatomical site, even if large.
• Do not use this code if the primary site is unknown or if the tumor is metastatic; instead, use codes from C76.- or C79.- as appropriate.