Computed tomography in staging of patients with melanoma metastatic to the regional nodes

European consensus-based interdisciplinary guideline for melanoma. Part 1: Diagnostics: Update 2022

Cutaneous melanoma (CM) is potentially the most dangerous form of skin tumor and causes 90% of skin cancer mortality. A unique collaboration of multi-disciplinary experts from the European Dermatology Forum (EDF), the European Association of Dermato-Oncology (EADO) and the European Organization for Research and Treatment of Cancer (EORTC) was formed to make recommendations on CM diagnosis and treatment, based on systematic literature reviews and the experts' experience. The diagnosis of melanoma can be made clinically and shall always be confirmed with dermatoscopy. If a melanoma is suspected, a histopathological examination is always required. Sequential digital dermatoscopy and full body photography can be used in high-risk patients to improve the detection of early melanoma. Where available, confocal reflectance microscopy can also improve clinical diagnosis in special cases. Melanoma shall be classified according to the 8th version of the American Joint Committee on Cancer classification. Thin melanomas up to 0.8 mm tumor thickness do not require further imaging diagnostics. From stage IB onwards, examinations with lymph node sonography are recommended, but no further imaging examinations. From stage IIC onwards whole-body examinations with computed tomography (CT) or positron emission tomography CT (PET-CT) in combination with brain magnetic resonance imaging are recommended. From stage III and higher, mutation testing is recommended, particularly for BRAF V600 mutation. It is important to provide a structured follow-up to detect relapses and secondary primary melanomas as early as possible. There is no evidence to define the frequency and extent of examinations. A stage-based follow-up scheme is proposed which, according to the experience of the guideline group, covers the optimal requirements, but further studies may be considered. This guideline is valid until the end of 2024.

Classification and Staging of Melanoma in the Head and Neck

The rates of melanoma continue to rise, with recent estimates have shown that 18% to 22% of new melanoma cases occur within the head and neck in the United States each year. The mainstay of treatment of nonmetastatic primary melanomas of the head and neck includes the surgical resection and management of regional disease as indicated. Thorough knowledge of the classification and staging of melanoma is paramount to evaluate prognosis, determine the appropriate surgical intervention, and assess eligibility for adjuvant therapy and clinic trials. The traditional clinicopathologic classification of melanoma is based on morphologic aspects of the growth phase and distinguishes 4 of the most common subtypes as defined by the World Health Organization: superficial spreading, nodular, acral lentiginous, and lentigo maligna melanoma. The data used to derive the AJCC TNM Categories are based on superficial spreading melanoma and nodular subtypes. Melanoma is diagnosed histopathologically following initial biopsy that will assist with classifying the tumor to guide treatment. Classification is based on tumor thickness and ulceration (T stage, Breslow Staging), Regional Lymph Node Involvement (N Stage), and presence of metastasis (M Stage). Tumor thickness (Breslow thickness) and ulceration are 2 independent prognostic factors that have been shown to be the strongest predictors of survival and outcome. Clark level of invasion and mitotic rate are no longer incorporated into the current AJCC staging system, but still have shown to be important prognostic factors for cutaneous melanoma. For patients with metastatic (Stage IV) disease Lactate Dehydrogenase remains an independent predictor of survival. The Maxillofacial surgeon must remain up to date on the most current management strategies in this patient population. Classification systems and staging provide the foundation for clinical decision making and prognostication for the Maxillofacial surgeon when caring for these patients.

In-transit metastatic cutaneous melanoma: current management and future directions

Management of in-transit melanoma encompasses a variety of possible treatment pathways and modalities. Depending on the location of disease, number of lesions, burden of disease and patient preference and characteristics, some treatments may be more beneficial than others. After full body radiographic staging is performed to rule out metastatic disease, curative therapy may be performed through surgical excision, intraarterial regional perfusion and infusion therapies, intralesional injections, systemic therapies or various combinations of any of these. While wide excision is limited in indication to superficial lesions that are few in number, the other listed therapies may be effective in treating unresectable disease. Where intraarterial perfusion based therapies have been shown to successfully treat extremity disease, injectable therapies can be used in lesions of the head and neck. Although systemic therapies for in-transit melanoma have limited specific data to support their primary use for in-transit disease, there are patients who may not be eligible for any of the other options, and current clinical trials are exploring the use of concurrent and sequential use of regional and systemic therapies with early results suggesting a synergistic benefit for oncologic response and outcomes.

Clinical benefit of baseline imaging in Merkel cell carcinoma: Analysis of 584 patients

BACKGROUND

Merkel cell carcinoma (MCC) guidelines derive from melanoma and do not recommend baseline cross-sectional imaging for most patients. However, MCC is more likely to have metastasized at diagnosis than melanoma.

OBJECTIVE

To determine how often baseline imaging identifies clinically occult MCC in patients with newly diagnosed disease with and without palpable nodal involvement.

METHODS

Analysis of 584 patients with MCC with a cutaneous primary tumor, baseline imaging, no evident distant metastases, and sufficient staging data.

RESULTS

Among 492 patients with clinically uninvolved regional nodes, 13.2% had disease upstaged by imaging (8.9% in regional nodes, 4.3% in distant sites). Among 92 patients with clinically involved regional nodes, 10.8% had disease upstaged to distant metastatic disease. Large (>4 cm) and small (<1 cm) primary tumors were both frequently upstaged (29.4% and 7.8%, respectively). Patients who underwent positron emission tomography-computed tomography more often had disease upstaged (16.8% of 352), than those with computed tomography alone (6.9% of 231; P = .0006).

LIMITATIONS

This was a retrospective study.

CONCLUSIONS

In patients with clinically node-negative disease, baseline imaging showed occult metastatic MCC at a higher rate than reported for melanoma (13.2% vs <1%). Although imaging is already recommended for patients with clinically node-positive MCC, these data suggest that baseline imaging is also indicated for patients with clinically node-negative MCC because upstaging is frequent and markedly alters management and prognosis.

Ultrasound, CT, MRI, or PET-CT for staging and re-staging of adults with cutaneous melanoma

BACKGROUND

Melanoma is one of the most aggressive forms of skin cancer, with the potential to metastasise to other parts of the body via the lymphatic system and the bloodstream. Melanoma accounts for a small percentage of skin cancer cases but is responsible for the majority of skin cancer deaths. Various imaging tests can be used with the aim of detecting metastatic spread of disease following a primary diagnosis of melanoma (primary staging) or on clinical suspicion of disease recurrence (re-staging). Accurate staging is crucial to ensuring that patients are directed to the most appropriate and effective treatment at different points on the clinical pathway. Establishing the comparative accuracy of ultrasound, computed tomography (CT), magnetic resonance imaging (MRI), and positron emission tomography (PET)-CT imaging for detection of nodal or distant metastases, or both, is critical to understanding if, how, and where on the pathway these tests might be used.

OBJECTIVES

Primary objectivesWe estimated accuracy separately according to the point in the clinical pathway at which imaging tests were used. Our objectives were:• to determine the diagnostic accuracy of ultrasound or PET-CT for detection of nodal metastases before sentinel lymph node biopsy in adults with confirmed cutaneous invasive melanoma; and• to determine the diagnostic accuracy of ultrasound, CT, MRI, or PET-CT for whole body imaging in adults with cutaneous invasive melanoma:○ for detection of any metastasis in adults with a primary diagnosis of melanoma (i.e. primary staging at presentation); and○ for detection of any metastasis in adults undergoing staging of recurrence of melanoma (i.e. re-staging prompted by findings on routine follow-up).We undertook separate analyses according to whether accuracy data were reported per patient or per lesion.Secondary objectivesWe sought to determine the diagnostic accuracy of ultrasound, CT, MRI, or PET-CT for whole body imaging (detection of any metastasis) in mixed or not clearly described populations of adults with cutaneous invasive melanoma.For study participants undergoing primary staging or re-staging (for possible recurrence), and for mixed or unclear populations, our objectives were:• to determine the diagnostic accuracy of ultrasound, CT, MRI, or PET-CT for detection of nodal metastases;• to determine the diagnostic accuracy of ultrasound, CT, MRI, or PET-CT for detection of distant metastases; and• to determine the diagnostic accuracy of ultrasound, CT, MRI, or PET-CT for detection of distant metastases according to metastatic site.

SEARCH METHODS

We undertook a comprehensive search of the following databases from inception up to August 2016: Cochrane Central Register of Controlled Trials; MEDLINE; Embase; CINAHL; CPCI; Zetoc; Science Citation Index; US National Institutes of Health Ongoing Trials Register; NIHR Clinical Research Network Portfolio Database; and the World Health Organization International Clinical Trials Registry Platform. We studied reference lists as well as published systematic review articles.

SELECTION CRITERIA

We included studies of any design that evaluated ultrasound (with or without the use of fine needle aspiration cytology (FNAC)), CT, MRI, or PET-CT for staging of cutaneous melanoma in adults, compared with a reference standard of histological confirmation or imaging with clinical follow-up of at least three months' duration. We excluded studies reporting multiple applications of the same test in more than 10% of study participants.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted all data using a standardised data extraction and quality assessment form (based on the Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2)). We estimated accuracy using the bivariate hierarchical method to produce summary sensitivities and specificities with 95% confidence and prediction regions. We undertook analysis of studies allowing direct and indirect comparison between tests. We examined heterogeneity between studies by visually inspecting the forest plots of sensitivity and specificity and summary receiver operating characteristic (ROC) plots. Numbers of identified studies were insufficient to allow formal investigation of potential sources of heterogeneity.

MAIN RESULTS

We included a total of 39 publications reporting on 5204 study participants; 34 studies reporting data per patient included 4980 study participants with 1265 cases of metastatic disease, and seven studies reporting data per lesion included 417 study participants with 1846 potentially metastatic lesions, 1061 of which were confirmed metastases. The risk of bias was low or unclear for all domains apart from participant flow. Concerns regarding applicability of the evidence were high or unclear for almost all domains. Participant selection from mixed or not clearly defined populations and poorly described application and interpretation of index tests were particularly problematic.The accuracy of imaging for detection of regional nodal metastases before sentinel lymph node biopsy (SLNB) was evaluated in 18 studies. In 11 studies (2614 participants; 542 cases), the summary sensitivity of ultrasound alone was 35.4% (95% confidence interval (CI) 17.0% to 59.4%) and specificity was 93.9% (95% CI 86.1% to 97.5%). Combining pre-SLNB ultrasound with FNAC revealed summary sensitivity of 18.0% (95% CI 3.58% to 56.5%) and specificity of 99.8% (95% CI 99.1% to 99.9%) (1164 participants; 259 cases). Four studies demonstrated lower sensitivity (10.2%, 95% CI 4.31% to 22.3%) and specificity (96.5%,95% CI 87.1% to 99.1%) for PET-CT before SLNB (170 participants, 49 cases). When these data are translated to a hypothetical cohort of 1000 people eligible for SLNB, 237 of whom have nodal metastases (median prevalence), the combination of ultrasound with FNAC potentially allows 43 people with nodal metastases to be triaged directly to adjuvant therapy rather than having SLNB first, at a cost of two people with false positive results (who are incorrectly managed). Those with a false negative ultrasound will be identified on subsequent SLNB.Limited test accuracy data were available for whole body imaging via PET-CT for primary staging or re-staging for disease recurrence, and none evaluated MRI. Twenty-four studies evaluated whole body imaging. Six of these studies explored primary staging following a confirmed diagnosis of melanoma (492 participants), three evaluated re-staging of disease following some clinical indication of recurrence (589 participants), and 15 included mixed or not clearly described population groups comprising participants at a number of different points on the clinical pathway and at varying stages of disease (1265 participants). Results for whole body imaging could not be translated to a hypothetical cohort of people due to paucity of data.Most of the studies (6/9) of primary disease or re-staging of disease considered PET-CT, two in comparison to CT alone, and three studies examined the use of ultrasound. No eligible evaluations of MRI in these groups were identified. All studies used histological reference standards combined with follow-up, and two included FNAC for some participants. Observed accuracy for detection of any metastases for PET-CT was higher for re-staging of disease (summary sensitivity from two studies: 92.6%, 95% CI 85.3% to 96.4%; specificity: 89.7%, 95% CI 78.8% to 95.3%; 153 participants; 95 cases) compared to primary staging (sensitivities from individual studies ranged from 30% to 47% and specificities from 73% to 88%), and was more sensitive than CT alone in both population groups, but participant numbers were very small.No conclusions can be drawn regarding routine imaging of the brain via MRI or CT.

AUTHORS' CONCLUSIONS

Review authors found a disappointing lack of evidence on the accuracy of imaging in people with a diagnosis of melanoma at different points on the clinical pathway. Studies were small and often reported data according to the number of lesions rather than the number of study participants. Imaging with ultrasound combined with FNAC before SLNB may identify around one-fifth of those with nodal disease, but confidence intervals are wide and further work is needed to establish cost-effectiveness. Much of the evidence for whole body imaging for primary staging or re-staging of disease is focused on PET-CT, and comparative data with CT or MRI are lacking. Future studies should go beyond diagnostic accuracy and consider the effects of different imaging tests on disease management. The increasing availability of adjuvant therapies for people with melanoma at high risk of disease spread at presentation will have a considerable impact on imaging services, yet evidence for the relative diagnostic accuracy of available tests is limited.

Development of radioiodine labeled acetaminophen for specific, high-contrast imaging of malignant melanoma

INTRODUCTION

Due to its poor prognosis, specific imaging for early detection of malignant melanoma is strongly desired. Although radioiodine labeled 4-hydroxyphenylcysteamine, which we previously developed, has good affinity for tyrosinase, an enzyme in the melanin metabolic pathway, image contrast of the melanoma:organ ratios is not sufficiently high for detection of primary melanoma and metastases at early injection times. In this study, we developed radioiodine labeled acetaminophen (I-AP) for specific, high-contrast imaging of malignant melanoma.

METHODS

Radioiodine-125-labeled AP (¹²⁵I-AP) was prepared using the chloramine-T method under no carrier-added conditions. Accumulation of radioactivity and the mechanism were evaluated in vitro using B16 melanoma cells incubated with ¹²⁵I-AP or ¹⁴C(U)-labeled AP (¹⁴C-AP) with and without l-tyrosine as a substrate of tyrosinase, phenylthiourea as an inhibitor of tyrosinase, and thymidine as an inhibitor of DNA polymerase. The biological distribution of radioactivity in B16 melanoma-bearing mice was evaluated to determine the accumulation of ¹²⁵I-AP. The stability of ¹²⁵I-AP over time was evaluated in mice.

RESULTS

The labeling efficiency and radiochemical purity of ¹²⁵I-AP were >80% and 95%, respectively. Accumulation of ¹²⁵I-AP was higher than that of ¹⁴C-AP at 60 min of incubation in vitro. The affinity of ¹⁴C-AP for tyrosinase and DNA polymerase was higher than that of ¹²⁵I-AP, whereas the V_max of ¹²⁵I-AP was higher than that of ¹⁴C-AP. ¹²⁵I-AP showed the highest accumulation in the gall bladder, and clearance from the blood and kidney was rapid. Melanoma:muscle and melanoma:normal skin ratios of ¹²⁵I-AP for imaging contrast were the highest at 15 min after injection, whereas the melanoma:blood and melanoma:bone ratios gradually increased over time. ¹²⁵I-AP remained stable for 60 min after injection in mice.

CONCLUSIONS

¹²⁵I-AP has affinity for tyrosinase and high image contrast at early time points after injection. Therefore, ¹²³I-AP imaging has great potential for specific, high-contrast detection of malignant melanoma. ADVANCES IN KNOWLEDGE: ¹²³I-AP will provide specific, high-contrast imaging for malignant melanoma at early injection times. IMPLICATIONS FOR PATIENT CARE: ¹²³I-AP has good potential for the diagnosis of malignant melanoma compared with ¹²³I-labeled 4-hydroxyphenylcysteamine, which we previously developed.

Benefits of initial CT staging before sentinel lymph node biopsy in patients with head and neck cutaneous melanoma

BACKGROUND

The value of CT at the time of diagnosis for patients with cutaneous head and neck melanoma clinically asymptomatic for metastatic disease is unclear.

METHODS

A retrospective medical chart review was performed on 198 consecutive patients identified with primary T1b-T4b head and neck melanoma clinically asymptomatic for metastatic disease referred for sentinel lymph node biopsy procedures between 2004 and 2014.

RESULTS

Initial CTs identified clinically occult melanoma metastases in 8.1% and advanced second primary tumors in 3.5% of patients. CT findings were false-negative in 1% and false-positive in 6% of patients. Overall survival (OS) for patients with true-positive CT findings was lower than for the other patients (P < .001).

CONCLUSION

CT imaging when staging patients with head and neck melanoma seems to identify more metastases than has been reported for melanoma at other sites. Preoperative CTs decreased the number of sentinel lymph node biopsy (SLNBs), thus avoiding the stress and cost of this surgical procedure in 12% of patients.

Melanoma patient imaging in the era of effective systemic therapies

Imaging plays a critical role in the current multi-disciplinary management of patients with melanoma. It is used for primary disease staging, surgical planning, and surveillance in high-risk patients, and for monitoring the effects of systemic or loco-regional therapies. Several different imaging modalities have been utilised in the past. Contemporary imaging practises vary geographically depending on clinical guidelines, physician preferences, availability and cost. Targeted therapies and immunotherapies have revolutionised the treatment of patients with metastatic melanoma over the last few years. With this have come new patterns of disease that were not observed after conventional therapies, and new criteria to assess therapeutic responses. In this article we review the role of imaging for patients with melanoma in the era of effective systemic therapies and discuss likely future developments.

Melanoma metastases in the abdomen and pelvis: Frequency and patterns of spread

AIM: To investigate the frequency, typical and atypical locations and patterns of melanoma metastases identifiable by computed tomography (CT) in the abdomen and pelvis.

METHODS: We performed a retrospective review of index CT examinations of the abdomen and pelvis in patients with melanoma and recorded all findings suggestive of metastatic disease.

RESULTS: Metastases were present on 36% (181/508) of the index examinations and most commonly involved the liver (47%) and pelvic lymph nodes (27%). Lower extremity primaries had the highest rate of metastasis (52%). Ocular and head and neck melanomas have a predilection to metastasize to the liver (hepatic involvement in 70% and 63%, respectively, of patients with metastatic disease) and metastases from lower extremity primaries most commonly involve pelvic lymph nodes (54% of patients with metastatic disease). Metastases to atypical locations were present in 14% of patients and most commonly occurred in the subcutaneous tissue and spleen. Primary tumors of the lower extremity, back and head and neck were most commonly associated with atypical metastases. Pelvic metastases are more common with lower extremity primaries (accounting for 70% of cases with pelvic metastases) but 5% of patients with supraumbilical primaries also had pelvic metastases.

CONCLUSION: The distribution of metastatic melanoma in the abdomen and pelvis that we have defined should help guide the interpretation of CT exams in these patients.

Outcomes for lymph node-positive cutaneous melanoma over two decades

BACKGROUND

Our aim was to demonstrate that, despite advances in treatment and surveillance of node-positive cutaneous melanoma, rates of overall survival (OS) and melanoma-specific survival (MSS) have not changed over the last two decades.

METHODS

We used the Surveillance, Epidemiology, and End Results (SEER) database of the National Cancer Institute to identify patients with node-positive cutaneous melanoma. Patients were categorized by treatment era; the first era encompassed patients diagnosed from 1988 to 1999 and the second era 2000 to 2006. Multivariate Cox proportional hazards models compared rates of OS and MSS between treatment eras while controlling for known prognostic factors. We reported risks of death as hazard ratios (HR) with 95% confidence intervals (CI) and set significance at P≤0.05.

RESULTS

Entrance criteria were met by 6,868 patients, 1,631 (23.8%) treated in era I and 5,237 (76.3%) treated in era II. On multivariate analysis, era II patients did not demonstrate a significantly different risk of death from any cause (HR 0.89, CI 0.79-1.01; P<0.08), but they did have a lower risk of melanoma-specific mortality (HR 0.81, CI 0.71-0.93; P=0.003) relative to their era I counterparts.

CONCLUSIONS

Over nearly two decades, MSS but not OS has improved for AJCC stage III melanoma patients. Stage migration is likely responsible for any improvement in MSS among patients in the most recently diagnosed era.

Guidelines of care for the management of primary cutaneous melanoma. American Academy of Dermatology

The incidence of primary cutaneous melanoma has been increasing dramatically for several decades. Melanoma accounts for the majority of skin cancer-related deaths, but treatment is nearly always curative with early detection of disease. In this update of the guidelines of care, we will discuss the treatment of patients with primary cutaneous melanoma. We will discuss biopsy techniques of a lesion clinically suspicious for melanoma and offer recommendations for the histopathologic interpretation of cutaneous melanoma. We will offer recommendations for the use of laboratory and imaging tests in the initial workup of patients with newly diagnosed melanoma and for follow-up of asymptomatic patients. With regard to treatment of primary cutaneous melanoma, we will provide recommendations for surgical margins and briefly discuss nonsurgical treatments. Finally, we will discuss the value and limitations of sentinel lymph node biopsy and offer recommendations for its use in patients with primary cutaneous melanoma.

Utility of 3-year torso computed tomography and head imaging in asymptomatic patients with high-risk melanoma

There is no general consensus regarding the optimal follow-up strategy for patients with melanoma. We sought to determine the utility and cost effectiveness of radiological restaging of patients with stage IIB-IIIC melanoma at the 3-year follow-up time point. A retrospective review of 210 patients diagnosed with stage IIB-IIIC melanoma seen in the Cutaneous Oncology Program at Beth Israel Deaconess Medical Center between January, 2001 and July, 2006 was conducted. Fifty-two patients were asymptomatic and continuously disease free and underwent restaging head computed tomography (CT) or MRI and torso CT scans 3 years after completion of local-regional therapy or initiation of adjuvant treatment. True positive, false positive and normal scans were identified and the cost per diagnosis calculated. Fifty-five percent of patients developed melanoma recurrences: 88% before 3 years (median time to recurrence 12 months, 95% confidence interval: 10-16 months). The majority of patients (69%) recurred with disease symptoms. Twenty-five head CT scans, 27 head MRIs, and 52 torso CTs were performed. One false-positive head CT and five abnormal torso CT scans (three false positive, two true positive) were identified. The total cost per diagnosis was $312,990. Extensive 3-year restaging imaging seems to be of limited value for symptomatic and continuously disease-free patients with stage IIB-IIIC melanoma. Furthermore, given the low risk of recurrence beyond 3 years, it is likely that subsequent routine imaging would have similarly low utility.

Treatment of cutaneous melanoma: current approaches and future prospects

Melanoma is the most aggressive and deadly type of skin cancer. Surgical resection with or without lymph node sampling is the standard of care for primary cutaneous melanoma. Adjuvant therapy decisions may be informed by careful consideration of prognostic factors. High-dose adjuvant interferon alpha-2b increases disease-free survival and may modestly improve overall survival. Less toxic alternatives for adjuvant therapy are currently under study. External beam radiation therapy is an option for nodal beds where the risk of local recurrence is very high. In-transit melanoma metastases may be treated locally with surgery, immunotherapy, radiation, or heated limb perfusion. For metastatic melanoma, the options include chemotherapy or immunotherapy; targeted anti-BRAF and anti-KIT therapy is under active investigation. Standard chemotherapy yields objective tumor responses in approximately 10%-20% of patients, and sustained remissions are uncommon. Immunotherapy with high-dose interleukin-2 yields objective tumor responses in a minority of patients; however, some of these responses may be durable. Identification of activating mutations of BRAF, NRAS, c-KIT, and GNAQ in distinct clinical subtypes of melanoma suggest that these are molecularly distinct. Emerging data from clinical trials suggest that substantial improvements in the standard of care for melanoma may be possible.

Treatment of cutaneous melanoma: current approaches and future prospects

Melanoma is the most aggressive and deadly type of skin cancer. Surgical resection with or without lymph node sampling is the standard of care for primary cutaneous melanoma. Adjuvant therapy decisions may be informed by careful consideration of prognostic factors. High-dose adjuvant interferon alpha-2b increases disease-free survival and may modestly improve overall survival. Less toxic alternatives for adjuvant therapy are currently under study. External beam radiation therapy is an option for nodal beds where the risk of local recurrence is very high. In-transit melanoma metastases may be treated locally with surgery, immunotherapy, radiation, or heated limb perfusion. For metastatic melanoma, the options include chemotherapy or immunotherapy; targeted anti-BRAF and anti-KIT therapy is under active investigation. Standard chemotherapy yields objective tumor responses in approximately 10%-20% of patients, and sustained remissions are uncommon. Immunotherapy with high-dose interleukin-2 yields objective tumor responses in a minority of patients; however, some of these responses may be durable. Identification of activating mutations of BRAF, NRAS, c-KIT, and GNAQ in distinct clinical subtypes of melanoma suggest that these are molecularly distinct. Emerging data from clinical trials suggest that substantial improvements in the standard of care for melanoma may be possible.

Prospective Comparison of [18F]Fluorodeoxyglucose Positron Emission Tomography and Computed Tomography in Patients With Melanoma With Palpable Lymph Node Metastases: Diagnostic Accuracy and Impact on Treatment

Purpose

Patients with melanoma with potentially resectable lymph node metastases require accurate staging to prevent unnecessary surgery. [18F]Fluorodeoxyglucose (FDG) positron emission tomography (PET) is attractive for this because melanoma typically is FDG avid. The aim of this prospective multicenter study was to perform a head-to-head comparison of FDG-PET and computed tomography (CT) in staging of patients with melanoma with palpable lymph node metastases in terms of diagnostic accuracy and impact on treatment.

Patients and Methods

All consecutive patients with palpable, proven lymph node metastases of melanoma between mid 2003 and 2007 were prospectively included. The number/site of distant metastases detected with FDG-PET and CT were recorded. Histology/cytology or 6 months follow-up were the reference standard. Intended and performed treatment was recorded.

Results

Distant metastases were suspected by FDG-PET in 32% of the 251 patients and by CT in 29% (P = .26). Upstaging was correct in 27% by FDG-PET and in 24% by CT (P = .18). FDG-PET detected more metastatic sites (133 v 112, P = .03), detecting significantly more bone and subcutaneous metastases. Treatment changed in 19% of patients; in 79% as a result of both scans, in 17% exclusively by FDG-PET, and in 4% exclusively by CT. In 34 patients (14%), FDG-PET had an additional value over spiral CT, and in 23 patients (9%), CT had additional value over FDG-PET.

Conclusion

As a result of FDG-PET and CT, 27% of patients were upstaged, and treatment changed in one of five patients. FDG-PET and CT are equivalent in upstaging; however, FDG-PET detected more metastatic sites, especially bone and subcutaneous. FDG-PET and/or CT are indicated in the staging of patients with melanoma with palpable lymph node metastases.

Staging of cutaneous melanoma

The American Joint Committee on Cancer (AJCC) staging of cutaneous melanoma is a continuously evolving system. The identification of increasingly more accurate prognostic factors has led to major changes in melanoma staging over the years, and the current system described in this review will likely be modified in the near future. Likewise, application of new imaging techniques has also changed the staging work-up of patients with cutaneous melanoma. Chest and abdominal computed tomography (CT) scanning is most commonly used for evaluation of potential metastatic sites in the lungs, lymph nodes and liver, and is indicated in patients with new symptoms, anaemia, elevated lactate dehydrogenase or a chest X-ray abnormality. CT scans should be restricted to patients with high-risk melanoma (stage IIC, IIIB, IIIC and stage IIIA with a macroscopic sentinel lymph node). Magnetic resonance imaging (MRI) of the brain is a mandatory test in patients with stage IV, optional in stage III and not used in patients with stage I and II disease. Positron emission tomography (PET)/CT is more accurate than CT or MRI alone in the diagnosis of metastases and should complement conventional CT/MRI imaging in the staging work-up of patients who have solitary or oligometastatic disease where surgical resection is most relevant.

Imaging in cutaneous melanoma

Cutaneous melanoma (CM) is a common malignancy and imaging, particularly lymphoscintigraphy (LS), positron-emission tomography with 2-fluoro-2-deoxyglucose (FDG-PET), ultrasound, radiography computed tomography (CT) and magnetic resonance imaging have important roles in staging and restaging, surgical guidance, surveillance and assessment of recurrent disease. This review aims to summarize the available data regarding these and other imaging modalities in CM and provide the basis for subsequent formulation of guidelines regarding the use of imaging in CM. PubMed and Medline searches were performed and reference lists from publications were also searched. The published data were reviewed and tabulated. There is level I evidence supporting the use of LS and sentinel lymph node biopsy in nodal staging for CM. There is level III evidence demonstrating the superiority of ultrasound to palpation in the assessment of lymph nodes in CM. There is level IV evidence supporting FDG-PET in American Joint Committee on Cancer stage III/IV and recurrent CM and that FDG-PET/CT may be superior to FDG-PET. Level IV evidence also supports the use of CT in the same group of patients and the role of CT appears to be complementary to FDG-PET. Various imaging modalities, especially LS/sentinel lymph node biopsy and FDG-PET/CT, add incremental information in the management of CM and the various modalities have complementary roles depending on the clinical situation.

Evaluation of staging chest radiographs and serum lactate dehydrogenase for localized melanoma

BACKGROUND

Radiographic and laboratory evaluations are often routinely used in the initial work-up for melanoma.

PURPOSE

To examine the yield of a chest radiograph and serum lactate dehydrogenase (LDH), in the work-up for newly diagnosed localized melanoma.

METHODS

Patients with a new diagnosis of localized invasive melanoma were entered into a prospective database. The status of the chest radiograph, LDH, and sentinel lymph node (SLN) was assessed.

RESULTS

Two-hundred-twenty-four patients were entered into the study and 210 had chest radiograph data for analysis. The true positive chest radiograph rate, defined as the percent of chest radiographs interpreted as "positive or equivocal possibly melanoma related" with subsequent confirmed melanoma metastases, was 0%. The false positive chest radiograph rate, defined as the percent of chest radiographs interpreted as "positive or equivocal possibly melanoma related" with melanoma metastases excluded based on previous or subsequent studies or other known medical conditions, was 7%. Ninety-six patients (melanoma> or =1 mm) had LDH results for analysis. Elevations in LDH were found in 15% and did not lead to detection of occult disease in any patients. Seventy-seven patients underwent SLN biopsy. A positive SLN did not correlate with abnormal chest radiograph or LDH.

CONCLUSION

Low yield, high rate of false-positive tests and lack of significant impact of early detection of metastases on survival argue that chest radiographs and serum lactate dehydrogenase should probably not be accepted into routine clinical practice in patients with clinically localized melanoma in the absence of data supporting their use.

Controversies in the management of metastatic melanoma to regional lymphatic basins

The primary management of lymph nodes involved with metastatic melanoma is regional lymphadenectomy. Many controversies of regional lymph node dissection exist including extent and nature of the lymphadenectomy, treatment of lymphatic metastases in unusual locations and the role of adjuvant radiotherapy. Although radical neck dissection has been the gold standard for cervical disease, modified dissections do not seem to compromise regional control in appropriately selected patients. In the axilla, a Level I, II, and III dissection is most commonly performed. Combined superficial and deep groin dissection is justified for clinically palpable disease although management of patients with histologically positive yet clinically non-palpable disease is more controversial. Burden of disease, imaging, patient co-morbidity, and Cloquet nodal status must be considered. Many technical variations exist in an attempt to improve morbidity rates secondary to lymphadenectomy. Unfortunately, complication rates are difficult to compare secondary to variable study designs, definitions, and patient populations. Adjuvant radiation therapy appears warranted in patients with high risk of regional recurrence including bulky disease, extracapsular extension or cervical location.

Vulvar Melanoma: Review of Diagnosis, Staging, and Therapy

OBJECTIVES

To update, assimilate, and bridge the contemporary literature on vulvar and cutaneous melanoma regarding diagnosis, staging, and therapy to provide a useful clinical reference for managing and counseling for affected patients.

MATERIALS AND METHODS

A computerized search for reports in the literature up to June 2003 was carried out using PubMed and MEDLINE databases. Multidisciplinary involvement was used in evaluating the available data and formulating conclusions.

RESULTS

More than 300 reports were reviewed. Diagnosis, staging, and therapy aspects of vulvar melanoma are summarized.

CONCLUSIONS

Vulvar melanoma represents a subtype of cutaneous melanoma, with similar prognostic and staging factors. The most recent American Joint Committee on Cancer staging system for cutaneous melanoma is applicable to vulvar melanoma. Sentinel lymph node biopsy is reliable for staging the regional lymph node basin for vulvar melanoma. Standardized documentation of clinical and histopathologic parameters is needed to standardize grouping of cases for future comparison studies.

Clinical role of FDG PET in evaluation of cancer patients

Positron emission tomography (PET) is a diagnostic imaging technique that allows identification of biochemical and physiologic alterations in tumors. Use of PET performed with 2-[fluorine-18]fluoro-2-deoxy-D-glucose (FDG) significantly improves the accuracy of tumor imaging. In terms of oncologic applications, FDG PET has already gained widespread acceptance in the initial staging of cancer, management of recurrent cancer, and monitoring the response to therapy. With conventional imaging modalities, size criteria are used to distinguish between benign and malignant disease in lymph nodes; conversely, FDG PET is based on identification of fundamental aspects of tumor metabolism. FDG uptake in tumors is proportional to the metabolic rate of viable tumor cells, which have an increased demand for glucose. The high sensitivity and high negative predictive value of FDG PET in most malignant tumors enable this technique to play an even greater role in tumor management at initial staging and follow-up.

Combined inguinal and pelvic lymph node dissection for stage III melanoma

BACKGROUND

The incidence of melanoma is increasing in the UK and a significant number of patients are still presenting with primary lesions of poor prognosis. As a consequence there is likely to be an increasing number of patients with lymph node metastases for whom the appropriate extent of groin dissection remains controversial. This review summarizes the evidence to enable surgeons to make an informed decision about the management of patients with melanoma metastases to the groin lymph nodes.

METHODS

A Medline search was performed to identify all English language articles about melanoma containing the words lymphadenectomy, lymph nodes, inguinal or lymphoedema. Eighty-seven relevant articles were selected from 3904 abstracts retrieved; 34 were related directly to the aim of this review.

RESULTS

There are no randomized controlled trials comparing the outcome of combined inguinal and pelvic lymph node dissection (CLND) and superficial inguinal lymph node dissection (SLND). Excision of pelvic lymph node metastases is reported to yield a 5-year survival rate of 0-35 per cent. Recurrence within the pelvis occurs in 9-18 per cent of patients after SLND and in less than 5 per cent after CLND. Morbidity following either CLND or SLND is poorly reported. Major long-term lymphoedema limiting patient activity affects 6-20 per cent of patients after groin dissection. Cloquet's node was demonstrated in one study to be a useful predictor of pelvic lymph node involvement. Patients may be selected for pelvic node dissection on the basis of clinical findings, the results of pelvic computed tomography and the status of Cloquet's node.

CONCLUSION

The controversy surrounding the appropriate management of cytologically positive inguinal nodes in melanoma can be resolved only by a prospective randomized trial comparing CLND with SLND. Morbidity and local disease control must be measured as outcomes in addition to disease-free and overall survival.

Laboratory tests and imaging studies in patients with cutaneous malignant melanoma

Laboratory tests and imaging studies are often ordered for asymptomatic patients with malignant melanomas (MMs) in an effort to detect subclinical metastatic disease. However, their sensitivity and specificity for detecting cryptic metastases are not well established. A review of the literature on laboratory tests and imaging studies for MM metastases was undertaken to address the usefulness of such investigations in asymptomatic patients with MM in AJCC (American Joint Committee on Cancer system of classification) stages I, II, and III. A review of the pertinent literature since 1966 was conducted through MEDLINE, Medica, and Cancerlit. Laboratory tests and imaging studies revealed occult MM metastases in only a small number of the thousands of reported patients with putative AJCC stage I, II, and III MM. However, for those diagnosed with limited metastases, surgical removal with or without immunotherapy, chemotherapy, or radiotherapy can lead to long-term remissions in some patients. For patients with asymptomatic AJCC stage I or II disease, chest roentgenograms (CXR) and blood lactic dehydrogenase (LDH) levels may be obtained at low cost and prove to be of benefit if metastases are identified. For patients with AJCC stage III disease, computed tomographic (CT) scans of the thorax, abdomen, and pelvis (especially when the primary cutaneous site of the melanoma is below the waist) may be considered for detecting metastatic MM. Other tests, such as magnetic resonance imaging (MRI) scans of the brain, may be ordered based on symptoms or physical findings. In the future, technologically improved techniques and newer methods may prove cost-effective for detecting treatable asymptomatic MM metastases. Furthermore, improvement in treatments will also influence the indications for the search for occult MM metastases. At this time there is a need for an international consensus conference on laboratory tests and imaging studies for occult melanoma metastases.

Classification and staging of melanoma

Although a standardized and uniformly accepted cancer staging system is an essential and fundamental requirement to enable meaningful comparisons across patient populations, the sometimes capricious biologic behavior of melanoma makes developing such a staging system particularly difficult. Since the earliest well-documented attempts at classifying patients with cutaneous melanoma were described more than 50 years ago, the identification of increasingly powerful prognostic factors has led to sequential modifications of the cutaneous melanoma staging system. The current AJCC staging system is based on relatively well-established prognostic factors; however, several recent reports have identified additional prognostic factors not included in the current system, and other studies support the re-evaluation of some of the currently employed staging criteria. Some of the more controversial areas include the relevance of level of invasion versus tumor thickness, optimal cutoffs for tumor thickness, importance of ulceration, the grouping of satellites with in-transit metastases, the inclusion of microsatellites and local recurrences as a separate staging criterion, the replacement of size of nodal mass with number of positive nodes, the importance of nodal metastases in more than one nodal basin, and the prognostic significance of distant metastases. Therefore, future modifications of the staging system are anticipated to better incorporate these observations. Stage-specific staging recommendations for the patient with melanoma provide the clinician with a framework to most efficiently assess extent of disease in an era of cost-conscious clinical practice. In the asymptomatic patient with primary melanoma (stage I or II), we recommend a chest roentgenogram and evaluation of alkaline phosphatase and LDH levels; extensive radiologic evaluations are not indicated, because the rate of detection in this population is extremely low. Additional staging information should also be obtained by the technique of lymphatic mapping and sentinel lymphadenectomy. For patients with local-regional disease (stage III, satellites, and local recurrence), a selective approach to imaging studies is warranted. For this patient population, we recommend complete blood count, liver function tests including alkaline phosphatase and LDH, a chest roentgenogram, and a CT scan of the abdomen. Although the yield of these tests, particularly CT of the abdomen, in detecting distant metastases in asymptomatic patients is low, they may identify false-positive abnormalities and provide an important baseline for future studies in this high-risk population. For patients with disease below the waist or in the head and neck region, we recommend CT of the pelvis and CT of the neck, respectively. Additional studies should be done only if clinically indicated. Finally, patients with known systemic disease (stage IV) should be more comprehensively evaluated, because the likelihood of detecting asymptomatic metastases is higher. Accordingly, in addition to the work-up outlined previously for stage III patients, we also perform a CT scan of the chest and MR imaging of the brain; other studies (e.g., bone scan, gastrointestinal series) are performed on the basis of symptoms.

Advances in melanoma therapy

This review discusses several advances in melanoma therapy that have recently occurred or are presently in a developmental stage. We discuss the history and present dogma regarding assessment of the regional lymph nodes and adjuvant therapy for melanoma. Of special interest is radiolymphatic sentinel node mapping of the lymph nodes and adjuvant interferon alfa-2b for thick primary lesions and stage III disease. We also discuss several evolving novel and innovative genetic immunotherapy approaches for patients with stage IV disease.