Journal of Surgical Oncology 2001;77:186±187

COMMENTARY

The use of intraoperative lymphatic mapping (IOLM)and sentinel node biopsy has substantially changed thetreatment of cutaneous melanoma. Ongoing argumentsover elective versus delayed node dissection have ended,replaced by widespread adoption of IOLM amongmelanoma surgeons worldwide. The single biggestvariable affecting success in IOLM is anatomic location.The lymphatic drainage patterns of the trunk, extremitiesand head and neck are all more variable than originallypredicted from cadaver studies. However, the head andneck presents surgeons with by far the greatestchallenges. The unique attributes of mapping in thehead and neck will challenge an experienced surgicaloncologist who performs IOLM predominantly formelanomas of the trunk and extremities. The head andneck is a three-dimensional (3D) anatomic area inter-twined with multiple nerves, cosmetic features, andboundaries. The `̀ shine-through'' problem limits thesurgeon's efforts to use preoperative lymphoscintigraphyto identify sentinel nodes that overlie radioactiveinjection sites. Combine the anatomic complexity withthe fact that the average surgical oncologist sees fewcases of head and neck melanoma, and the result is alearning curve that can be slow and sometimes painful.Conversely, the experienced head and neck surgeonrarely has a high volume of melanoma mapping cases,and cannot leverage the experience that surgicaloncologists derive from performing sentinel nodebiopsies below the clavicle.

Put these technical complexities and turf issuestogether, and it is no surprise that the acceptance ofIOLM for melanoma has been slowest in the head andneck. Meanwhile, controversies abound about indica-tions, techniques, and adjunctive therapies to be used forhead and neck melanoma patients. It is in this settingthat Gibbs et al. offer their review of surgical therapy ofhead and neck melanoma. The `̀ bottom line'' is that theypresent no compelling reasons to believe the surgicaltreatment of melanomas in this location should befundamentally different than elsewhere in the body.They suggest that IOLM and sentinel node biopsy willbecome standard care for head and neck melanomapatients.

But are we there yet? Head and neck IOLM, like IOLMfor melanomas elsewhere, has improved signi®cant

because of technical improvements in probe design anda better understanding of the anatomic variations. Ourexperience in trunk and extremity melanoma has taughtus to aggressively interrogate multiple drainage sites toidentify node-positive patients or exclude unnecessarynode dissections if only one site is positive. The courageto attack the parotid in search of sentinel nodes hasallowed surgeons to learn to ®nd individual lymph nodeswithin the con®nes of parotid tissue without injury to thefacial nerve. So the answer appears to be yes, thechallenges posed by IOLM in the head and neck can behandled by the well-trained surgical oncologist or headand neck surgeon operating as part of an experiencedmultidisciplinary team.

There are still, however, many opportunities toimprove IOLM in the head and neck. Prospective clinicaltrials will be necessary to de®ne the limits of use. Forexample, what is the lower threshold of lesion thicknessfor IOLM? Conversely, what are the bene®ts of IOLM inpatients with deep melanomas (>4 mm) where, althoughregional failure is a major issue, traditional wisdomargued against elective node dissection? When micro-metastases are found within the sentinel nodes, what ifany modi®cations of standard neck dissection proceduresshould be made? What adjuvant therapies, such asradiation and high-dose interferon-a, should be used inthe sentinel node-positive patients? Outside the strictlymedical sphere, we must also wonder whether reimburse-ment concerns will cloud the picture in the head and neckif clear data are not available to demonstrate ef®cacy ofIOLM?

We believe that IOLM in the head and neck is apowerful tool to stage and treat melanoma, withextraordinarily high degrees of patient acceptance. Atour center, a multidisciplinary approach has allowedgeneral surgical oncologists and head and neck surgeonsto work side-by-side and bene®t from each others'expertise. Identical indications are applied to IOLMfor head and neck melanomas as for those occurringelsewhere on the skin: all patients with melano-mas �1.00 mm and selected patients with melanomas<1 mm (speci®cally those with ulceration, extensiveregression or a positive deep margin) are potentialcandidates. Likewise, the same approaches to adjuvanttherapy are taken, with sentinel node-positive patients

ß 2001 Wiley-Liss, Inc.

evaluated for adjuvant high-dose interferon-a, andpostoperative radiotherapy reserved for patients withgross extranodal extension or multiple positive nodes(situations rarely encountered when clinically negativenodes are found to have microscopic involvement). If thereport by Gibbs et al. serves to motivate surgeons to putaside preconceived notions and apply consistent surgicalstandards to melanomas arising above and below theclavicle, it will be a valuable contribution indeed.

Riley Rees, MD

Vernon K. Sondak, MD

Department of SurgcrySection of Plastic Surgery and

Division of Surgical OncologyMultidisciplinary Melanoma ClinicUniversity of MichiganComprehensive Cancer CenterAnn Arbor, Michigan

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