When new Current Procedural Terminology (CPT)* codes 49186–49190 for open excision or destruction of peritoneal, mesenteric, and retroperitoneal tumors were created for CPT 2025, the intent was to better reflect differences in surgeon work, disease processes, and patient populations.
The CPT instructional guidelines provide definitions and examples to clarify the services reported. However, early implementation has revealed the need for additional clarification to support accurate coding by surgeons and professional coders.
This article provides additional clarity for the reporting of these complex procedures and to improve accuracy in documenting tumor excision involving “orphaned organs,” such as peritoneal or retroperitoneal tissues.
Accurate documentation must reflect the work actually performed, while ensuring that all distinct, reportable services are captured. The examples included in the CPT guidelines were designed to illustrate this balance—particularly to avoid duplicate reporting of excisions involving masses that arise from specific organs. When masses are resected, they may require additional organ removal consistent with oncologic principles.
A key distinction among codes 49186–49190 is whether the mass arises from a particular organ or within separate peritoneal or retroperitoneal tissue. If the mass originates from an organ, the appropriate organ resection code should be reported, not a code from the 49186–49190 family. For example, excision of a mass arising from the colon should be reported with the appropriate colectomy code, and resection of a renal cell carcinoma should be reported with a nephrectomy code.
Conversely, resection or destruction of a mass arising from peritoneal tissue—requiring independent dissection, stripping, or destruction—should be measured in vivo (excluding margins) and reported cumulatively using the applicable tumor excision or destruction code. The primary consideration for accurate reporting is determining where the mass arises: whether its removal is inherent to an organ resection or represents distinct, additional work.
Following implementation of the new codes, several inquiries have focused on retroperitoneal resections. When resection of a retroperitoneal mass requires removal of adjacent organs, those organ resections may be separately reported if the dissection of each organ represents distinct work beyond that required for the retroperitoneal mass itself. Oncologic resections are often described as en bloc to indicate that the tumor and tissue planes were not violated during removal. This terminology does not imply that organ resections are bundled; separate reporting remains appropriate when distinct dissection and resection work are documented.
The following examples describe correct reporting practices:
- Example 1: A patient with a 22-cm left retroperitoneal liposarcoma involving the left kidney, tail of the pancreas, and spleen undergoes complete resection. Distinct dissections of both the retroperitoneal mass and the invaded organs are documented. Appropriate reporting would include excision of retroperitoneal mass (49189), nephrectomy (50220), and distal pancreatectomy with splenectomy (48140), with modifier 51 or 59 as appropriate. The operative report must clearly document that the organ dissection is distinct from the retroperitoneal mass removal.
- Example 2: A patient with a mass arising from the adrenal gland should be reported only as an adrenalectomy (60545).
- Example 3: A patient undergoes excision of a 7-cm mass (excluding margins) involving retroperitoneal tissue and the abdominal wall. The procedure should be reported solely with the tumor excision code (49187).
If excision of a peritoneal, mesenteric, or retroperitoneal mass does not require separate organ dissection, control of hilar or mesenteric blood supply, or perioperative work associated with organ resection, then additional organ codes should not be reported. However, large, complex oncologic resections—such as those for extensive retroperitoneal sarcomas—often involve distinct perioperative considerations beyond the primary mass excision. These include physiological implications of organ removal and management of postoperative complications such as pancreatic leak, infection following splenectomy, or renal function concerns after nephrectomy.
- If the mass arises from an organ, report only the organ resection code.
- If the mass arises from peritoneal, mesenteric, or retroperitoneal tissue but requires adjacent organ resection, report both the appropriate mass excision and organ resection codes.
- Document the cumulative excision size based on the in situ measured sum of the maximum length of each tumor or cyst excised or destroyed.
- Only the tumors and cysts are measured, not the margins or the tissue (e.g., mesentery) in which the tumors and cysts may be implanted.
As part of the ACS’s ongoing efforts to help members and their practices submit clean claims and receive proper reimbursement, a coding consultation service—the ACS Coding Hotline—has been established for coding and billing questions. ACS members are offered five free consultation units (CUs) per calendar year. One CU is a period of up to 10 minutes of coding services time. Access the ACS Coding Hotline website at prsnetwork.com/acshotline.
Dr. Megan McNally is a surgical oncologist at Saint Luke’s Health System in Kansas City, Missouri, and assistant clinical professor in the Department of Surgery at the University of Missouri-Kansas City School of Medicine. She also is a member of the ACS General Surgery Coding and Reimbursement Committee and the ACS advisor to the AMA CPT Editorial Panel.
*All specific references to CPT codes and descriptions are © 2025 American Medical Association. All rights reserved. CPT is a registered trademark of the American Medical Association.
