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Treatment and biopsy of lymph nodes in neoplastic disease remain controversial (Gilson 1995). It is demonstrated that lymph node size (Langenbach et al. 2001; Williams and Packer 2003) and needle aspirates are not great at detecting metastases (Ku et al. 2017; Fournier et al. 2018). Removing a lymph node or performing an incisional biopsy of a lymph node can aid in staging the patient and assist in the determination of prognosis or treatment options. The surgical oncologist should have a thorough knowledge of the anatomic location of the probable draining lymph node for a mass in a particular location. Alternatively, sentinel lymph node detection techniques such as lymphography and scintigraphy can be used (see Chapter 14). The excisional biopsy of superficial lymph nodes such as the mandibular, superficial cervical (prescapular), axillary, inguinal, or popliteal lymph nodes is described below. For removal of lymph nodes within the thorax or abdomen, an exploration of that body cavity is performed and the lymph nodes are removed by careful dissection and maintenance of hemostasis.

Instrumentation includes a #10 or #15 blade, Metzenbaum scissors, forceps, Mayo scissors, and suture. The surgical site is clipped free of fur, and the patient is prepared with aseptic technique and draped. An incision slightly larger than the palpable lymph node is made parallel to the axis of the lymph node. The superficial tissue overlying the lymph node is bluntly and sharply dissected. The lymph node capsule is then grasped with the forceps and blunt and/or sharp dissection is performed around the lymph node to free it from the surrounding tissue. Vessels that are encountered may need to be ligated. The lymph node is then removed, and the subcutaneous tissue and skin are closed. Many “lymph nodes” are actually lymphocenters. The implication is that multiple lymph nodes can be present in one location, for example, the mandibular lymphocenter often has two to three lymph nodes.

Figure 1.5 (a) Jamshidi needle (left) with the two stylets (middle and right). The stylet in the middle is used to approach the bone. The stylet to the right is used to remove the sample from the needle after being acquired. (b) The end of the needle is tapered, helping to keep the sample in the needle when the needle is removed from the bone. (c) To remove the sample from the needle, the stylet is introduced through the tip of the needle and the sample is pushed to exit the base at the handle. In some instances, there is too much resistance to push the sample out of the handle end, in which case the first stylet is used to push the sample out through the tip. It is not ideal because in theory the sample can suffer some damage going through the narrowed end, but sometimes it is necessary.