Note: All recommendations are category 2A unless otherwise indicated.
Margins
An overarching goal of oncologic surgery is complete tumor resection with histologic verification of tumor-free margins. Margin assessment may be in real time by frozen section or by assessment of formalin-fixed tissues. Tumor-free margins are an essential surgical strategy for diminishing the risk for local tumor recurrence. Conversely, positive margins increase the risk for local relapse and are an indication for postoperative
adjuvant therapy. Clinical pathologic studies have demonstrated the significance of close or positive margins and their relationship with local tumor recurrence. When there is an initial cut-through with an invasive tumor at the surgical margin, obtaining additional adjacent margins from the patient may also be associated with a higher risk for local relapse. Obtaining additional margins from the patient is subject to ambiguity regarding whether the tissue taken from the surgical bed corresponds to the actual site of margin positivity.
Frozen section margin assessment is always at the discretion of the surgeon and should be considered when it will facilitate complete tumor removal. The achievement of adequate wide margins may require resection of an adjacent structure in the oral cavity or laryngopharynx such as the base of tongue and/or anterior tongue, mandible, larynx, or portions of the cervical esophagus.
Adequate is defined as clear resection margins with at least enough clearance from the gross tumor to obtain clear frozen section and
permanent margins (often 1.5-2 cm of visible and palpable normal mucosa). In general, frozen section examination of the margins will usually be undertaken intraoperatively, and importantly, when a line of resection has uncertain clearance because of indistinct tumor margins, or there is suspected residual disease (ie, soft tissue, cartilage, carotid artery, or mucosal irregularity).
The details of resection margins should be included in the operative dictation. The margins may be assessed on the resected specimen or alternatively from the surgical bed with proper orientation.
A clear margin is defined as the distance from the invasive tumor front that is 5 mm or more from the resected margin. A close margin is defined as the distance from the invasive tumor front to the resected margin that is less than 5 mm. A positive margin is defined as carcinoma in situ or as invasive carcinoma at the margin of resection.
The primary tumor should be marked in a fashion adequate for orientation by the surgical pathologist. The primary tumor should be assessed histologically for depth of invasion and for distance from the invasive portion of the tumor to the margin of resection, including the peripheral and deep margins. The pathology report should be template driven and describe how the margins were assessed. The report should provide information regarding the primary specimen to include the distance from the invasive portion of the tumor to the peripheral and deep margin. If the surgeon obtains additional margins from the patient, the new margins should refer back to the geometric orientation of the resected tumor specimen with a statement by the pathologist that this is the final margin of resection and its histologic status.
The neck dissection should be oriented or sectioned in order to identify levels of lymph nodes encompassed in the dissection.
Reconstruction of surgical defects should be performed using conventional techniques at the discretion of the surgeon. Primary closure is recommended when appropriate but should not be pursued at the expense of obtaining wide, tumor-free margins. Reconstructive closure with local/regional flaps, free-tissue transfer, or split-thickness skin or other grafts with or without mandibular reconstruction is performed at the discretion of the surgeon.
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2Looser KG, Shah JP, Strong EW. The significance of "positive" margins in surgically resected epidermoid carcinomas. Head Neck Surg 1978;1:107-111.
Scholl P, Byers RM, Batsakis JG, et al. Microscopic cut-through of cancer in the surgical treatment of squamous carcinoma of the tongue. Prognostic and therapeutic implications. Am J Surg 1986;152:354-360.
Version 2.2013, 05/29/13 © National Comprehensive Cancer Network, Inc. 2013, All rights reserved. The NCCN Guidelines and this illustration may not be reproduced in any form without the express written permission of NCCN®.®
Discussion
Note: All recommendations are category 2A unless otherwise indicated.
Clinical Trials: NCCN believes that the best management of any cancer patient is in a clinical trial. Participation in clinical trials is especially encouraged.
Head and Neck Cancers
Surgical Management of Cranial Nerves VII, X (including the recurrent laryngeal nerve), XI, and XII
Operative management of the facial nerve and other major cranial nerves during primary or regional node resection is influenced by the preoperative clinical function of the nerve.
When the nerve is functioning, thorough efforts should be made to preserve the structure and function of the nerve (main trunk and/or
branches)--even if otherwise adequate tumor margins are not achieved--recognizing that the surgeon should leave no gross residual disease. Adjuvant postoperative radiation or chemoradiation is generally prescribed when a microscopic residual or gross residual tumor is
suspected.
Direct nerve invasion by a tumor and/or preoperative paralysis of the nerve may warrant segmental resection (and sometimes nerve grafting) at the discretion of the surgeon if tumor-free margins are assured throughout the remainder of the procedure.
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SURG-A