Has Placement of Surgical Clips in the Lumpectomy Bed Fallen Out of Favor?

Abstract

Surgical clips were originally developed in the early 1900s, and initially utilized for hemostasis in intracranial operations. Since then, the clinical applications of surgical clips have broadened to include procedures across all surgical disciplines. In oncologic procedures, surgeons may place clips in the cavity of a tumor bed for a myriad of reasons, with the most common being to control hemostasis; other uses include placement to mark extent of dissection, denote anatomic location during a future operation or for accuracy of postoperative imaging. Another value of surgical clips is technical efficiency, which may allow for decreased operative time. In reality, appreciation for surgical clip application extends beyond the surgical theater. Just as surgeons rely on percutaneously placed clips to target a nonpalpable lesion for wire localization, radiation oncologists rely on clips in the tumor bed to accurately delineate the surgical cavity, as postoperative changes on computed tomography (CT) scans may be difficult to visualize. Typically, surgical clips are made of titanium or steel, both of which are radio opaque and can be visualized on plain film or CT scans. In early-stage breast cancer, clips placed in the surgical bed at time of definitive surgical resection have traditionally been used by radiation oncologists to direct the boost treatment after whole-breast irradiation. More recently, however, with the advent of accelerated partial-breast irradiation (APBI) using external-beam radiation therapy, detection and delineation of the surgical cavity are of even greater importance, given the large radiotherapy fraction doses delivered over a short period of time. Accurate delineation of lumpectomy cavity target volumes by relying on seroma formation or location of lumpectomy incision has been shown to be largely inaccurate. The seroma is a postoperative serous fluid accumulation and is sometimes used to estimate the lumpectomy cavity borders when no metallic marker is present. Seroma formation after lumpectomy, however, is variable, making it difficult to assess the true cavity borders accurately. The lumpectomy incision scar has also been used in an effort to define lumpectomy borders, but accuracy in this technique has also been unsuccessful. In a small, prospective series by Krawczyk and colleagues, measurement from lumpectomy scar to breast tissue border was found to be an inadequate prediction tool for radiation planning. In fact, relying on the lumpectomy scar may result in a significant risk of underdosing of the lumpectomy cavity. From a radiation oncologist perspective, it may be best for clips to be placed along all margins of a cavity to improve targeted radiation therapy. In fact, published data from our group suggest that directed placement of fiducial markers on the walls of the surgical cavity allowed for improved interphysician accuracy in delineation of the lumpectomy cavity. However, in many centers, including ours, surgical clip placement is left to surgeon discretion. To our knowledge, no standard recommendation for clip placement exists, and patterns of variation have prompted discussion amongst radiation oncologist and breast surgical oncologist at our institution. Multiple studies over the past 10–20 years have evaluated the clinical importance of surgical clip placement in radiotherapy planning. In 2008, Coles et al. performed an audit of titanium clip placement utilized in the Society of Surgical Oncology 2011