What is pre-operative tumour marking?
Pre-operative tumour marking is the placement of special markers like hook wires and coils inside the tumour under image guidance. Tumour marking may also include a colouring agent to aid in visualising the lesion.
Pre-operative tumour marking may be used to assist surgeons in the removal of tumour tissue by clearly defining the margins of the tumour. This will help a surgeon during the removal procedure by allowing them to both see and feel the edges of the tumour. This means the surgeon can remove as much of the tissue surrounding the tumour as possible, greatly reducing the need for further surgical procedures to remove further tissue. An imaging technique, such as mammography, CT or magnetic resonance may be employed to visualise the tumour.
How does the procedure work?
Pre-operative tumour marking is mainly used for tumours in the breast and lung. There are different types of tumour marking materials. The main purpose of these materials is to make the target lesion easy to find.
The IR will introduce the materials into the lesion of interest with the use of a puncture needle that is placed through the skin under image guidance. The most frequently used method of marking changes in the breast that cannot be seen or felt is the use of special hook wires that are “anchored” in the selected breast area.
To confirm that the tumour can be completely removed, the IR will perform a preparation X-ray, which also allows them to evaluate the marked edges of the tumour. It is possible to use pre-operative coil-marking of tumours in muscles and bones with the use of MR guidance.
Why perform it?
Pre-operative tumour marking is widely used in cases of breast lesions where it would otherwise be difficult to be sure of the exact margins of the tumour. About half of breast cancers in surgical practice are non-palpable in examination.
These patients are candidates for breast conserving therapy (BCT). It is crucial to remove the tumour with a proper margin of healthy tissues which minimises the need for further surgery.
Localisation markers can be applied to virtually all parts of the body. They offer perfect guidance for the surgeon, and surgical results can improve significantly with a reduced operation time.
What are the risks?
Intra-operative complications are related to the technique itself and include bleeding, bruising, infection and, if the patient has pulmonary lesions, pneumothorax (the abnormal collection of gas or air in the space between the lung and the chest wall). Dislocation of the marker can also occur between the time of pre-operative marking and surgery. All of these complications are extremely rare.
Bibliography
1. Pereira PL1, Fritz J, Koenig CW, Maurer F, Boehm P, Badke A, Mueller-Schimpfle M, Bitzer M, Claussen CD. Preoperative marking of musculoskeletal tumors guided by magnetic resonance imaging. J Bone Joint Surg Am. 2004 Aug; 86-A(8):1761-7.
2. Masaya Tamura, Makoto Oda, Hideki Fujimori, Yosuke Shimizu, Isao Matsumoto, Go Watanabe. New indication for preoperative marking of small peripheral pulmonary nodules in thoracoscopic surgery Interactive CardioVascular and Thoracic Surgery 11 (2010) 590–593.
3. Beata A, Pawel M. Preoperative localization of nonpalpable breast nodules – which method to choose? Reports of Practical Oncology & Radiotherapy Volume 13, Issue 4, July–August 2008, Pages 202–2.