Structures present in Radical neck node resection

Radical neck dissection (RND) was attributed to Crile in 1906 and was considered the gold standard for the removal of nodal metastases (Fig. 33-4). Through a subsequent close reading of Crile's surgical notes, it was found that he had begun to modify his surgical technique to remove only selected regions of the neck, depending on the site of the primary tumor; this has become common surgical practice for HNSCC at the present time. All modifications of neck dissection are described in relation to the standard RND, which removes nodal levels I through V and the sternocleidomastoid muscle, internal jugular vein, cranial nerve XI, cervical plexus, and submandibular gland. Preservation of the sternocleidomastoid muscle, internal jugular vein, or cranial nerve XI in any combination is referred to as a modified RND, and the structures preserved are specified for nomenclature. A modified neck dissection may also be referred to as a Bocca neck dissection, named after the surgeon who demonstrated that not only is modi- fied RND equally as effective in controlling neck disease as RND when structures are preserved that are not directly involved in tumor, but also the functional outcomes of patients after modified RND are superior to functional outcomes after RND.18 Although resection of the sternocleidomastoid muscle or one internal jugular vein is relatively nonmorbid, loss of cranial nerve XI leaves a denervated trapezius muscle, which can cause a painful chronic frozen shoulder. RND or modified RND can be performed for removal of detectable nodal disease. Preservation of any of levels I through V during neck dissection is referred to as selective neck dissection and is based on knowledge of the patterns of spread to neck regions. Selective neck dissection is performed on a clinically negative (N0) neck, with preservation of nodal groups carrying less than a 20% chance of being involved with metastatic disease. Regional control has been shown to be as effective after selective neck dissection as after modified RND in patients with a clinically negative neck. Studies evaluating treatment of an N0 neck inves- tigated the use of sentinel lymph node biopsy, which attempts to predict the disease status of the neck based on the first echelon of nodes that drain the tumor.19 Although sentinel lymph node biopsy has been used extensively with melanoma, its use in HNSCC has come about more gradually. Early results using iso- sulfan blue dye alone suggested that this technique cannot con- sistently identify the sentinel node in HNSCC. More recent results using a gamma probe were more encouraging, although the isolated node should be serial step-sectioned at a thickness of 150 nm and be examined through permanent processing. Recom- mendations at the present time are that the technique should be restricted to early-stage (T1 or T2) oral and oropharyngeal cancers, with clinically N0 necks; the gamma probe continues to be an investigational tool pending validation by large randomized clini- cal trials. Ref: sabiston 20th edition Pgno: 794