Mucosal melanoma (MM) is a rare, very aggressive noncutaneous melanoma that affects the upper aerodigestive tract, genitourinary tract, and anal/rectal region.1 This portion of the NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for Head and Neck (H&N) Cancers only describes MMs of the H&N, which constitute fewer than 10% of melanomas of the H&N.1,2 Note that a separate NCCN Guideline is available for cutaneous melanoma (see NCCN Guidelines for Melanoma, available in this issue and online at www.NCCN.org).
NCCN Clinical Practice Guidelines in Oncology for Mucosal Melanoma of the Head and Neck
NCCN Categories of Evidence and Consensus
Category 1: Based upon high-level evidence, there is uniform NCCN consensus that the intervention is appropriate.
Category 2A: Based upon lower-level evidence, there is uniform NCCN consensus that the intervention is appropriate.
Category 2B: Based upon lower-level evidence, there is NCCN consensus that the intervention is appropriate.
Category 3: Based upon any level of evidence, there is major NCCN disagreement that the intervention is appropriate.
All recommendations are category 2A unless otherwise noted.
Clinical trials: NCCN believes that the best management for any cancer patient is in a clinical trial. Participation in clinical trials is especially encouraged.
The full NCCN Guidelines for H&N Cancers address tumors arising in the upper aerodigestive tract (i.e., lip, oral cavity, pharynx, larynx, paranasal sinuses; see Figure 1). Occult primary cancer, salivary gland cancer, and MM are also addressed.3 Many of the approaches for managing H&N cancer are also applicable to MM (e.g., multidisciplinary team, surgical principles). To view the full NCCN Guidelines for H&N Cancers, visit the NCCN Web site at www.NCCN.org.
By definition, the NCCN Guidelines cannot incorporate all possible clinical variations and are not intended to replace good clinical judgment or individualization of treatments. Exceptions to the rule were discussed among the members of the NCCN H&N Cancers Panel while developing these guidelines.
The staging system for MM begins with stage III disease, which is the most limited form of disease for MM (see Workup and Staging, page 333).4 Surgery (with or without radiation therapy [RT]) is the primary treatment for stage III MM, whereas surgery followed by RT or systemic therapy is the primary treatment for stage IV MM, depending on systemic involvement.
Multidisciplinary Team Involvement
The initial evaluation and development of a plan for treating patients with MM require a multidisciplinary team of health care providers with expertise in caring for these patients. Similarly, managing and preventing sequelae of radical surgery, RT, and chemotherapy (e.g., pain, xerostomia, speech and swallowing problems, depression) require professionals familiar with the disease. Follow-up for these sequelae should include a comprehensive H&N examination. Adequate nutritional support can help to prevent severe weight loss in patients undergoing treatment for MM; therefore, patients should be encouraged to see a dietician.5
Patients should also be encouraged to stop smoking and to modify alcohol consumption if excessive, because these habits may decrease the efficacy of treatment and adversely affect other health outcomes.6,7 Programs using behavioral counseling combined with medications that promote smoking cessation (approved by the FDA) can be very useful (http://www.ahrq.gov/clinic/tobacco/tobaqrg.htm). Specific components of patient support and follow-up are listed in the algorithm (see Team Approach, in the NCCN Guidelines for H&N Cancers, available online at www.NCCN.org [TEAM-1]). Notably, patients with MM require timely diagnosis and management of depression. The H&N Cancers Panel also recommends referring to the NCCN Guidelines for Palliative Care (to view the most recent version of these guidelines, visit the NCCN Web site at www.NCCN.org).
Comorbidity and Quality of Life
Comorbidity refers to the presence of concomitant disease (in addition to MM) that may affect the diagnosis, treatment, and prognosis of the patient.8–10 Documentation of comorbidity is particularly important in oncology to facilitate optimal treatment selection and estimates of prognosis. Comorbidity is known to be a strong independent predictor of mortality in patients with H&N cancer,10–17 and comorbidity also influences costs of care, use of treatment, and quality of life.18–20 Traditional indices of comorbidity include the Charlson index9 and the Kaplan-Feinstein index and its modifications.10,21 The Adult Comorbidity Evaluation-27 (ACE-27) is specific for H&N cancer and has excellent emerging reliability and validity.22,23
Quality of Life
Health-related quality-of-life issues are paramount in H&N cancer and MM. These tumors affect basic physiologic functions (e.g., ability to chew, swallow, and breathe), the senses (e.g., taste, smell, hearing), and uniquely human characteristics (e.g., appearance, voice). Health status describes an individual’s physical, emotional, and social capabilities and limitations. Function and performance refer to how well an individual is able to perform important roles, tasks, or activities. The definition of quality of life differs, because the central focus is on the value (determined by the patient alone) that individuals place on their health status and function.24
Mucosal Melanoma of the Head and Neck
MM of the H&N is a rare but highly aggressive neoplasm with a poor prognosis. It may occur throughout the upper aerodigestive tract. Most MM of the H&N (∼70%) occurs in the nasal cavity or paranasal sinus region, and approximately 25% develops in the oral cavity (see Figure 2).4,25 The remainder develops in other sites (e.g., oropharynx, hypopharynx, larynx). Sinonasal MM is typically confined to the primary site at presentation, and patients often present with symptoms (e.g., nasal obstruction).2,26 Oral cavity MM more frequently presents with clinically apparent lymph node metastasis and is often asymptomatic.27 No etiologic risk factors are yet apparent. MM occurs in a greater extent in Asians and less frequently in the Western population.28
Workup and Staging
Diagnosis of MM of the H&N can be difficult. The differential diagnosis of sinonasal MM includes lymphoma, sarcoma, and olfactory neuroblastoma.29 Ideally, a combination of histology, immunohistochemistry, and clinical features is used for diagnosis. MM is immunoreactive for S-100 and HMB-45 (and to a lesser extent for melan-A); however, MM is negative for cytokeratin.2,29
Workup for MM should include clinical examination and CT and/or MRI for paranasal sinus disease, and appropriate imaging for other mucosal sites. The physical examination should include endoscopic inspection for paranasal sinus disease. PET/CT scanning may be considered to define the presence of distant disease in more advanced situations.
The AJCC Staging Manual (7th edition) includes a staging system for MM (see Table 6 in the NCCN Guidelines for H&N, available online, at www.NCCN.org [ST-11])4; previous editions did not have a classification for MM. The AJCC staging recognizes 2 key factors specific to MM: 1) the disease still has a poor prognosis even with a limited primary burden of disease, and 2) there is still some gradation of survival based on the burden of disease, as reflected in local, regional, and distant extent.
Thus, the AJCC staging system for MM begins with stage III disease as the most limited form of disease (similar to anaplastic thyroid carcinoma), and breaks the disease down into stages reflecting local burden of disease and regional and distant extent. Melanomas confined to the mucosa only are T3, those with moderately advanced lesions (involving underlying cartilage or bone) are T4a, and very advanced primary tumors are T4b. In addition, the AJCC staging system reflects the fact that MM occurs at all mucosal sites in the H&N. Therefore, rules for classifying and staging, and surgical principles should be based on the appropriate anatomic site of origin (see the NCCN Guidelines for H&N Cancers, available online, at www.NCCN.org).
Treatment of the Primary
Although limited data are available on treatment options, surgery is the primary treatment for MM stage III through IVA (see Principles of Surgery on pages 326–329 and in the NCCN Guidelines for H&N Cancers, available online at www.NCCN.org [SURG-A]).30 However, surgery is not recommended for stage IVB or IVC disease.31 The panel strongly encourages clinical trials for all patients with MM to better define treatment choices at all stages of disease.
In most case series, adjuvant RT seems effective in improving local control and survival.32 RT is clearly indicated in more advanced cases as an adjunct to surgery (see the Principles of Radiation Therapy on page 330 and in the NCCN Guidelines for H&N Cancers, available online at www.NCCN.org [RAD-A]).33 The role of radiation in stage III disease is not clear, but it can be considered and should be determined on an individual basis by the treating clinicians. However, survival rates after surgery alone or surgery combined with radiation are better than those after radiation alone.30
Treatment of the Neck
Neck dissection and postoperative radiation are recommended for clinical nodal disease.34,35 The role of elective neck treatment is unclear.36 The extension of elective treatment to the neck seems unwarranted in most cases of N0 paranasal sinus MM. However, for oral cavity disease, the likelihood of positive disease is significantly higher and the treatment can be better localized to the ipsilateral neck with both surgery and radiation (see Principles of Surgery on pages 326–329 and in the NCCN Guidelines for H&N Cancers, available online at www.NCCN.org [SURG-A]). Therefore, elective treatment to the neck for oral cavity MM seems justifiable.
Prospective trials evaluating the role of RT in MM are lacking. However, recently reported results of a randomized trial in cutaneous melanoma are considered relevant to MM in the postoperative setting after neck dissection.37 Retrospective studies in MM have shown local recurrence to be common after surgery alone.30,38,39 After using postoperative radiation, lower rates of local and neck recurrence have been seen in historical comparison series.32,40 Reasonable local control outcomes using RT alone in unresectable or medically inoperable cases have been reported in small cohort series of MMs.30,41–44
RT is often recommended in the postoperative management of MMs. Primary size or thickness is not used as a risk factor when considering RT to the primary site; all invasive primaries are considered at high risk for local recurrence. For sinonasal primary sites, target volumes may include the primary site without elective treatment of the neck. Because oral cavity primary sites are believed to be at a higher risk for failure in the neck, elective management with neck dissection and RT may be applied.
Indications for postoperative radiation to the neck are generally extrapolated from cutaneous melanoma. Recently, an Australian-New Zealand consortium reported on a randomized trial (N = 250) of postoperative RT versus observation in patients with palpable adenopathy from cutaneous primaries. Post-operative RT was associated with a significant reduction in relapse in the nodal basin (19% vs. 31%) and a significant improvement in lymph node field control.37 Only 20 patients experienced disease relapse who underwent postoperative RT, compared with 34 patients who underwent observation only (P = .04).
Considering this trial and retrospective studies in MM, the panel recommends postoperative RT for the following high-risk features: extracapsular disease, involvement of 2 or more neck or intraparotid nodes, any node 3 cm or greater, neck excision (alone) with no further basin dissection, or recurrence in the neck or soft tissue after initial surgical resection.45,46 Conventional fractionation is recommended (at 2 Gy per fraction to a total postoperative dose of 60–66 Gy, or to 70 Gy for gross disease). Although the Australian-New Zealand randomized trial used 48 Gy in 20 fractions (240 cGy per fraction) to neck, axilla, or groin,37 the NCCN H&N Cancers Panel prefers conventional fractionation to somewhat higher total doses (60–66 Gy) in the neck because of concerns about late effects from larger dose per fraction, which may not be fully expressed for many years after treatment.
Intensity modulated RT may be very helpful for achieving homogenous dose distributions and sparing of critical organs, especially in paranasal sinus sites (see Radiation Techniques on page 331).47–49 Good outcomes have been reported with the use of hypofractionation in cutaneous melanomas, which has the advantage of convenience but no clear advantage in cancer control. There is little experience using large dose per fraction in mucosal sites. Because of the proximity of neural structures and risk of late effects, hypofractionation (if used) must be carefully planned and delivered.
Systemic therapy used for cutaneous melanoma (e.g., interleukin-2) is recommended for MM (see Systemic Therapy Options for Advanced or Metastatic Melanoma in the NCCN Guidelines for Melanoma, available in this issue on pages 378–380 and online at www.NCCN.org [ME-E]). Interferon and interleukin have been used to treat MM.50 Data suggest that c-KIT inhibitors (e.g., imatinib) may be useful in patients with metastatic MM who have specific c-KIT mutations (i.e., exon 11 or 13 mutations).28,51 Therefore, imatinib is reasonable to use in patients with MM who have c-KIT mutations.52 Although vemurafenib is recommended for patients with cutaneous melanoma who have the V600E mutation of the BRAF gene, patients with MM rarely have this BRAF mutation.51
Recommendations for surveillance are provided in the algorithm (see Follow-Up Recommendations on page 325). Note that physical examination should include endoscopic inspection for paranasal sinus disease. Salvage surgery may be useful for patients with MM; therefore, surveillance is important.30
Recurrent or Persistent Disease
For patients with MM who have recurrent or persistent disease, the NCCN H&N Cancers Panel recommends using the NCCN Guidelines for Melanoma (available in this issue and online at www.NCCN.org).
Principles of Surgery
All patients should be evaluated by an H&N surgical oncologist before being treated for MM. In addition, multidisciplinary evaluation and treatment must be well coordinated. Many surgical principles described in the NCCN Guidelines for H&N Cancers algorithm are applicable to MM (i.e., evaluation, integration of therapy, assessment of resectability, primary tumor resection, margins, management of recurrences, and surveillance; see Principles of Surgery on pages 326–329 and in the NCCN Guidelines for H&N Cancers, available online at www.NCCN.org [SURG-A]).3,53 Resectable disease, neck dissection, and salvage surgery of high-risk disease are discussed in the following sections.
Resectable Versus Unresectable Disease
The term unresectable has resisted formal definition by H&N cancer specialists. The experience of the surgeon and the support available from reconstructive surgeons, physiatrists, and prosthodontists often strongly influence recommendations, especially in institutions in which only a few patients with MM are treated. The NCCN Member Institutions have teams experienced in the treatment of H&N cancer and maintain the multidisciplinary infrastructure needed for reconstruction and rehabilitation. A patient’s cancer is deemed unresectable if H&N surgeons at NCCN Member Institutions do not think they can remove all gross tumor on anatomic grounds or if they are certain local control will not be achieved after surgery (even with the addition of RT to the treatment approach). Typically, these unresectable tumors densely involve the cervical vertebrae, brachial plexus, deep muscles of the neck, or carotid artery (see Principles of Surgery on pages 326–329 and in the NCCN Guidelines for H&N Cancers, available online at www.NCCN.org [SURG-A]). Tumor involvement of certain sites is associated with poor prognosis (e.g., direct extension of neck disease to involve the external skin or to mediastinal structures, prevertebral fascia, or cervical vertebrae).
Unresectable tumors (i.e., those that cannot be removed without causing unacceptable morbidity) should be distinguished from inoperable tumors in patients whose constitutional state precludes an operation (even if the cancer could be readily resected with few sequelae). Additionally, a subgroup of patients will refuse surgical management, but these tumors should not be deemed unresectable. Although local and regional disease may be surgically treatable, patients with distant metastases are usually treated as though the primary tumor was unresectable. This is balanced by the potential to mitigate suffering from local and regional disease. This may be particularly true in MM. Thus, patient choice or a physician’s expectations regarding cure and morbidity will influence or determine treatment.
Historically, cervical lymph node (i.e., neck) dissections have been classified as radical or modified radical procedures. The less-radical procedures preserve the sternocleidomastoid muscle, jugular vein, spinal accessory nerve, or selective lymph node levels. The NCCN H&N Cancers Panel prefers to classify cervical lymphadenectomy using contemporary nomenclature, thus classifying cervical lymph node dissections as either comprehensive or selective.54 A comprehensive neck dissection is one that removes all lymph node groups that would be included in a classic radical neck dissection. Whether the sternoclei-domastoid muscle, jugular vein, or spinal accessory nerve is preserved does not affect whether the dissection is classified as comprehensive. Depending on the site, comprehensive neck dissection is often recommended for patients with positive nodal disease MM (see Neck Management in Principles of Surgery on pages 326–329 and in the NCCN Guidelines for H&N Cancers, available online at www.NCCN.org [SURG-A]). In general, elective neck dissections for melanoma are not performed, except for oral cavity. Currently, elective treatment of the neck tends to be reserved for when access to vessels is needed for microvascular anastomosis for free flaps and perhaps in oral cavity primary MM.
For a therapeutic dissection, whether the neck can be made more selective will depend on the primary location of the tumor. Level I disease may be cleared with a selective neck dissection encompassing levels I through IV, and pharyngeal disease may not require a level I dissection.55,56 For example, to remove the nodes most commonly involved with metastases from the oral cavity, a selective neck dissection is recommended, which includes the nodes found above the omohyoid muscle (levels I–III and sometimes the superior parts of level V).54,57 Similarly, to remove the nodes most commonly involved with metastases from the pharynx and larynx, a selective neck dissection is recommended, which includes the nodes in levels II through IV and level VI when appropriate.54 Selective neck dissections may be used as treatment when neck tumor burden is low.55,56
Salvage surgery may be useful for patients with MM; therefore, surveillance is important.30 However, the NCCN H&N Cancers Panel emphasized the increased risk of complications when salvage surgery is attempted. Some of these patients may require microvascular free flap reconstruction to cover the defects at the primary site. The patients undergoing neck dissection may develop complications related to delayed wound healing, skin necrosis, or carotid exposure.
Individual Disclosures for the NCCN Guidelines Panel for Mucosal Melanoma of the Head and Neck
BurmeisterBHendersonMThompsonJ. Adjuvant radiotherapy improves regional (lymph node field) control in melanoma patients after lymphadenectomy: results of an Intergroup Randomized Trial (TROG 02.01/ANZMTG 01.02) [abstract]. Int J Radiat Oncol Biol Phys2009;75:S2.