Tumour thickness as a predictor of occult lymph node metastases in patients with stage I and II melanoma undergoing sentinel lymph node biopsy

MelRisk: Using neutrophil-to-lymphocyte ratio to improve risk prediction models for metastatic cutaneous melanoma in the sentinel lymph node

BACKGROUND

Identifying metastatic melanoma in the sentinel lymph node (SLN) is important because 80% of SLN biopsies are negative and 11% of patients develop complications. The neutrophil-to-lymphocyte ratio (NLR), a biomarker of micrometastatic disease, could improve prediction models for SLN status. We externally validated existing models and developed 'MelRisk' prognostic score to better predict SLN metastasis.

METHODS

The models were externally validated using data from a multicenter cohort study of 1,251 adults. Additionally, we developed and internally validated a new prognostic score `MelRisk', using candidate predictors derived from the extant literature.

RESULTS

The Karakousis model had a C-statistic of 0.58 (95% CI, 0.54-0.62). The Sondak model had a C-statistic of 0.57 (95% CI 0.53-0.61). The MIA model had a C-statistic of 0.60 (95% CI. 0.56-0.64). Our 'MelRisk' model (which used Breslow thickness, ulceration, age, anatomical site, and the NLR) showed an adjusted C-statistic of 0.63 (95% CI, 0.56-0.64).

CONCLUSION

Our prediction tool is freely available in the Google Play Store and Apple App Store, and we invite colleagues to externally validate its performance .

Epidemiology, management and survival outcomes of primary cutaneous melanoma: a ten-year overview

BACKGROUND

Malignant melanoma (MM) is the most aggressive type of skin cancer, accounting for 90% of all the skin cancer mortality. The objective of this study was providing an overview of current patient- and tumour characteristics, treatment strategies, complications and survival in patients with MM over the past ten years. Hereby, an up-to-date view of every day clinical practice is obtained.

METHODS

Files of patients treated for primary cutaneous melanoma (n = 686) in the VieCuri Medical Centre in the Netherlands between January 2002 and December 2013 were retrospectively reviewed. Relevant patient features, tumour characteristics, and (surgical) outcomes were evaluated.

RESULTS

The majority of all the patients presented thin tumours (59.1% stage 1A/in situ melanoma). Men showed more ulceration (17.7% vs. 8.4%, p < .01) and a significantly higher Breslow thickness than women (1.2 mm vs. 0.9 mm, p < .01). 14.6% (40/273) underwent sentinel lymph node biopsy (SLNB); 10/40 (25%) showed nodal metastasis, 50 patients (7.3%) developed distant metastases (M: 10.6%, F: 5%, p < .01). One-, 5- and 10- year disease specific survival rates were 96%, 86% and 84%, respectively. Median survival for stage 4 MM was 3 months. Extensive surgery was uncommon (n = 3).

CONCLUSIONS

Patients generally presented with thin melanomas. Lymph node disease and distant metastases remained infrequently observed during following years, and general 1- and 5-year overall disease-specific survival rates exceeded 85%. Small numbers of rescue surgery and palliative medical treatment warrant further centralisation and investigation.

Sentinel Lymph Node Biopsy in Cutaneous Melanoma: Standard and New Technical Procedures and Clinical Advances. A Systematic Review of the Literature

Melanoma is an important public health problem, and its incidence is increasing worldwide. The disease status of regional lymph nodes is the most important prognostic factor in early-stage melanoma patients. Sentinel lymph node biopsy (SLNB) was introduced in the early 1990s as a less invasive procedure than complete lymph node dissection to allow histopathologic evaluation of the "sentinel lymph node" (SLN), which is the first node along the lymphatic pathway from a primary tumor. Sentinel lymph node biopsy has minimal complication risks compared with standard complete lymph node dissection. Currently, SLNB is the accepted method for staging patients with clinically node-negative cutaneous melanoma and provides the most powerful prognostic information by evaluating the nodal basin status. The current practice of SLNB consists of the injection of Tc-labeled radiopharmaceutical, preoperative lymphoscintigraphy with the possibility of using the SPECT/CT hybrid imaging, and intraoperative SLN localization using a handheld gamma probe with or without the use of blue dye. Recently, the SLN localization and detection have been enhanced with the use of new tracers and new intraoperative devices, which have demonstrated to be particularly useful in melanomas of the head and neck region and in area of complex anatomy. Despite these important advances in the technology and the increasing experience in SLN mapping, major research centers have reported a false-negative rate higher than 15%. This relatively high false-negative rate, greater than those reported in the initial validation studies, points out the importance for the nuclear medicine community to continuously improve their knowledge on the biological behavior of melanoma and to improve the technical aspects that may allow more precise staging. For the SLNB procedure to be accurate, it is of critical importance that all "true" SLNs are identified and removed for examination. The aim of this article is to provide general information about the SLNB procedure in clinical practice highlighting the importance of standardization and accuracy of SLN identification in the light of the most recent technical innovations.

Dermal melanoma: A report on prognosis, outcomes, and the utility of sentinel lymph node biopsy

INTRODUCTION

Historically dermal melanoma (DM) has been labeled as either stage IIIB (in-transit) or stage IV (M1a) disease. We sought to investigate the natural history of DM and the utility and prognostic significance of sentinel lymph node biopsy (SLNB).

METHODS

Patients with DM undergoing SLNB at a single center from 1998 to 2009 were identified.

RESULTS

Eighty-three patients met criteria, 10 (12%) patients had a positive SLNB. Of those, 5 (50%) recurred (all with distant disease). Twenty-one (29%) of the 73 SLNB negative patients recurred and of those, 15 (71%) developed distant metastases, whereas 6 (29%) developed local or regional recurrence, including two false-negative regional nodal recurrences. No in-transit recurrences were recorded. Five-year recurrence-free and disease-specific survival was significantly better for patients with a negative SLNB versus positive SLNB (56.8% vs. 22.2% P = 0.02, 81.1% vs. 61.0%, P = 0.05, respectively).

CONCLUSION

SLNB has prognostic significance for RFS and DSS, and should be utilized in the management of DM based on a >10% yield and low false-negative rate. Our data demonstrate patients with DM do not recur in an in-transit fashion, which along with the survival outcomes suggest the behavior of DM is consistent with primary cutaneous melanoma of similar thickness rather than an isolated in-transit or distant dermal metastasis from a regressed cutaneous primary.

Probabilistic issues with sentinel lymph nodes in malignant melanoma

OBJECTIVES

To address issues of probability for sentinel lymph node results in melanoma and provide details about the probabilistic nature of the numbers of sentinel nodes as well as to address how these issues relate to tumor thickness and patient outcomes.

METHODS

Analysis of the probability of observing sentinel node metastases uses the discrete exponential probability distribution to address the number of observed positive sentinel nodes. In addition, mathematical functions derived from survival analysis are used. Data are then chosen from the literature to illustrate the approach and to derive results.

RESULTS

Observations about the numbers of positive and negative sentinel nodes closely follow discrete exponential probability distributions, and the relationship between the probability of a positive sentinel node and tumor thickness follows closely a function derived from survival analysis. Sentinel node results relate to tumor thickness as well as to the total number of nodes harvested but fall short of identifying all those who eventually develop metastatic melanoma.

CONCLUSIONS

Probability analyses provide useful insight into the success and failure of the sentinel node biopsy procedure in patients with melanoma.

Update and Review on the Surgical Management of Primary Cutaneous Melanoma

The surgical management of malignant melanoma historically called for wide excision of skin and subcutaneous tissue for any given lesion, but has evolved to be rationally-based on pathological staging. Breslow and Clark independently described level and thickness as determinant in prognosis and margin of excision. The American Joint Committee of Cancer (AJCC) in 1988 combined features from each of these histologic classifications, generating a new system, which is continuously updated and improved. The National Comprehensive Cancer Network (NCCN) has also combined several large randomized prospective trials to generate current guidelines for melanoma excision as well. In this article, we reviewed: (1) Breslow and Clark classifications, AJCC and NCCN guidelines, the World Health Organization's 1988 study, and the Intergroup Melanoma Surgical Trial; (2) Experimental use of Mohs surgery for in situ melanoma; and (3) Surgical margins and utility and indications for sentinel lymph node biopsy (SLNB) and lymphadenectomy. Current guidelines for the surgical management of a primary melanoma of the skin is based on Breslow microstaging and call for cutaneous margins of resection of 0.5 cm for MIS, 1.0 cm for melanomas ≤1.0 mm thick, 1-2 cm for melanoma thickness of 1.01-2 mm, 2 cm margins for melanoma thickness of 2.01-4 mm, and 2 cm margins for melanomas >4 mm thick. Although the role of SLNB, CLND, and TLND continue to be studied, current recommendations include SLNB for Stage IB (includes T1b lesions ≤1.0 with the adverse features of ulceration or ≥1 mitoses/mm²) and Stage II melanomas. CLND is recommended when sentinel nodes contain metastatic deposits.

MicroRNAs in the pathogenesis of malignant melanoma

Cutaneous malignant melanoma is the most aggressive and lethal form of skin cancer. Over the past decades, its incidence has been increasing by 3-8% per year in western countries while mortality has stabilized. Melanoma is a heterogenous disease and can be subclassified based on distinct clinical characteristics, histopathological features and mutation patterns within NRAS and BRAF genes. Recent data indicate that microRNAs (miRNAs) are involved in the pathogenesis of malignant melanoma. MiRNAs are small, non-coding, regulatory RNA molecules expressed in a tissue and cell specific manner and are known to play a crucial role in cell homeostasis and carcinogenesis. MiRNAs might prove to be powerful cancer biomarkers and future therapeutic targets. In this review, we focused on the miRNA involvement in four molecular pathways known to be deregulated in malignant melanoma, including the RAS-RAF-MEK-ERK pathway, the p16(INK4A) -CDK4-RB pathway, the PIK3-AKT pathway and the MITF pathway.

Validation of statistical predictive models meant to select melanoma patients for sentinel lymph node biopsy

INTRODUCTION

To identify melanoma patients at sufficiently low risk of nodal metastases who could avoid sentinel lymph node biopsy (SLNB), several statistical models have been proposed based upon patient/tumor characteristics, including logistic regression, classification trees, random forests, and support vector machines. We sought to validate recently published models meant to predict sentinel node status.

METHODS

We queried our comprehensive, prospectively collected melanoma database for consecutive melanoma patients undergoing SLNB. Prediction values were estimated based upon four published models, calculating the same reported metrics: negative predictive value (NPV), rate of negative predictions (RNP), and false-negative rate (FNR).

RESULTS

Logistic regression performed comparably with our data when considering NPV (89.4 versus 93.6%); however, the model's specificity was not high enough to significantly reduce the rate of biopsies (SLN reduction rate of 2.9%). When applied to our data, the classification tree produced NPV and reduction in biopsy rates that were lower (87.7 versus 94.1 and 29.8 versus 14.3, respectively). Two published models could not be applied to our data due to model complexity and the use of proprietary software.

CONCLUSIONS

Published models meant to reduce the SLNB rate among patients with melanoma either underperformed when applied to our larger dataset, or could not be validated. Differences in selection criteria and histopathologic interpretation likely resulted in underperformance. Statistical predictive models must be developed in a clinically applicable manner to allow for both validation and ultimately clinical utility.

Melanoma sentinel node biopsy and prediction models for relapse and overall survival

BACKGROUND

To optimise predictive models for sentinal node biopsy (SNB) positivity, relapse and survival, using clinico-pathological characteristics and osteopontin gene expression in primary melanomas.

METHODS

A comparison of the clinico-pathological characteristics of SNB positive and negative cases was carried out in 561 melanoma patients. In 199 patients, gene expression in formalin-fixed primary tumours was studied using Illumina's DASL assay. A cross validation approach was used to test prognostic predictive models and receiver operating characteristic curves were produced.

RESULTS

Independent predictors of SNB positivity were Breslow thickness, mitotic count and tumour site. Osteopontin expression best predicted SNB positivity (P=2.4 × 10⁻⁷), remaining significant in multivariable analysis. Osteopontin expression, combined with thickness, mitotic count and site, gave the best area under the curve (AUC) to predict SNB positivity (72.6%). Independent predictors of relapse-free survival were SNB status, thickness, site, ulceration and vessel invasion, whereas only SNB status and thickness predicted overall survival. Using clinico-pathological features (thickness, mitotic count, ulceration, vessel invasion, site, age and sex) gave a better AUC to predict relapse (71.0%) and survival (70.0%) than SNB status alone (57.0, 55.0%). In patients with gene expression data, the SNB status combined with the clinico-pathological features produced the best prediction of relapse (72.7%) and survival (69.0%), which was not increased further with osteopontin expression (72.7, 68.0%).

CONCLUSION

Use of these models should be tested in other data sets in order to improve predictive and prognostic data for patients.

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.

Vascular invasion is an early event in pathogenesis of Merkel cell carcinoma

This study investigated vascular and especially lymphovascular invasion in primary Merkel cell carcinoma and its value as a prognostic factor. Paraffin-embedded blocks prepared from tumor samples obtained from 126 patients diagnosed with Merkel cell carcinoma in 1979-2004 were immunohistochemically stained using antibodies CD31 and D2-40 to detect intravascular tumor emboli. This finding was compared with the clinical data and the disease outcome. Intravascular tumor cells were observed in 117 (93%) of the samples. The majority, 83 (66%), showed only lymphovascular invasion. Only blood vascular invasion was seen in four (3%) samples. In all, 30 (24%) samples demonstrated both lymphovascular invasion and blood vascular invasion. In only nine (7%) samples, there was no invasion within the vascular structures. The tumors lacking invasion were significantly smaller (P<0.01 and alpha=0.050) than those with vascular invasion, although lymphovascular invasion was observed even in the smallest tumor (0.3 cm) of this study. Already in the early stages of the disease, Merkel cell carcinoma seems to have the capacity to penetrate vessel walls. Our finding of the high frequency of lymphovascular invasion might therefore explain the extremely aggressive clinical behavior of Merkel cell carcinoma. This may support the role of sentinel node biopsy even in the case of very small primary Merkel cell carcinoma tumors.

Toward better management of merkel cell carcinoma using a consensus staging system, new diagnostic codes and a recently discovered virus

Merkel cell carcinoma (MCC) is a neuroendocrine skin cancer with a higher propensity for recurrence and metastasis than melanoma or squamous cell carcinoma. Despite aggressive behavior and the tripling of its reported incidence in the past 20 years, there is extensive confusion about how MCC should be managed. Here we address two issues that have impeded optimal MCC management: lack of a consensus staging system and lack of unique diagnostic codes for MCC. Five conflicting systems currently used to stage MCC will be replaced by one system in 2010 that will diminish confusion about prognosis and management among physicians and patients. The diagnostic bundling of MCC with numerous less aggressive skin cancers leads to care refusals by insurance and an inability to track MCC care costs. Worldwide adoption in 2009 of specific diagnostic codes for MCC will also improve understanding and management of this often-lethal skin cancer.

Sentinel lymph node biopsy in melanoma patients

Appropriate surgical management of regional lymph nodes is critical in patients with cutaneous melanoma. The use of intraoperative lymphatic mapping and sentinel lymph node biopsy (SLNB) has increased significantly in the past decade. SLNB is performed as minimally invasive procedure that provides accurate staging of melanoma patients with no clinically detectable nodal disease. In many melanoma units across the world, it became the standard for detection of occult regional node metastasis in patients with intermediate-thickness primary melanoma. Use of SLNB in patients with thin melanomas is still under evaluation. Although SLNB has been established as staging procedure in melanoma patients, its therapeutic role is still not clear. Large-scale ongoing randomized trials should elucidate whether SLNB with complete lymphadenectomy has a survival benefit in melanoma patients with early lymph node metastases compared to 'watch-and-wait' policy (observation).

Melanoma biomarkers: current status and utility in diagnosis, prognosis, and response to therapy

Melanoma is the most devastating form of skin cancer and represents a leading cause of cancer death, particularly in young adults. As even relatively small melanomas can readily metastasize, accurate staging of progression is critical. Diagnosis is typically made on the basis of histopathologic criteria; with tumor thickness (Breslow), invasion level (Clark), ulceration, and the extent of lymph node involvement being important prognostic indicators. However, histologic criteria alone cannot diagnose all melanomas and there are often problems in distinguishing subsets of benign nevi from melanoma. There also exists a group of patients with thin primary melanomas for whom surgery should be curative but who ultimately go on to develop metastases. Therefore, there is an urgent need to develop molecular biomarkers that identify melanoma patients with high-risk primary lesions to facilitate greater surveillance and possible adjuvant therapy. The advent of large-scale genomic profiling of melanoma is revealing considerable heterogeneity, suggesting that melanomas could be subgrouped according to their patterns of oncogenic mutation and gene expression. It is hoped that this subgrouping will allow for the personalization of melanoma therapy using novel molecularly targeted agents. Much effort is now geared toward defining the genetic markers that may predict response to targeted therapy agents as well as identifying pharmacodynamic markers of therapy response. In this review, we discuss the utility of melanoma biomarkers for diagnosis and prognosis and suggest how novel molecular signatures can help guide both melanoma diagnosis and therapy selection.

EANM-EORTC general recommendations for sentinel node diagnostics in melanoma

The accurate diagnosis of a sentinel node in melanoma includes a sequence of procedures from different medical specialities (nuclear medicine, surgery, oncology, and pathology). The items covered are presented in 11 sections and a reference list: (1) definition of a sentinel node, (2) clinical indications, (3) radiopharmaceuticals and activity injected, (4) dosimetry, (5) injection technique, (6) image acquisition and interpretation, (7) report and display, (8) use of dye, (9) gamma probe detection, (10) surgical techniques in sentinel node biopsy, and (11) pathological evaluation of melanoma-draining sentinel lymph nodes. If specific recommendations given cannot be based on evidence from original, scientific studies, referral is given to "general consensus" and similar expressions. The recommendations are designed to assist in the practice of referral to, performance, interpretation and reporting of all steps of the sentinel node procedure in the hope of setting state-of-the-art standards for good-quality evaluation of possible spread to the lymphatic system in intermediate-to-high risk melanoma without clinical signs of dissemination.

Sentinel lymph node biopsy for melanoma: indications and rationale

BACKGROUND

The disease status of regional lymph nodes is the most important prognostic indicator for patients with melanoma. Sentinel lymph node biopsy (SLNB) was developed as a technique to surgically assess the regional lymph nodes and spare node-negative patients unnecessary and potentially morbid complete lymphadenectomies.

METHODS

We reviewed the literature on SLNB for cutaneous melanoma to provide insight into the rationale for the current widespread use of SLNB.

RESULTS

Multiple studies show that the status of the SLN is an important prognostic indicator. Those with positive SLNs have significantly decreased disease-free and melanoma-specific survival compared with those who have negative SLNs. In the Multicenter Selective Lymphadenectomy Trial I (MSLT-I), in which patients with intermediate-thickness melanoma were randomized to SLNB (and immediate completion lymphadenectomy if the SLN was positive) vs observation (and a lymphadenectomy only after presenting with clinically evident recurrence), the 5-year survival rate was 72.3% for patients with positive sentinel nodes and 90.2% for those with negative sentinel nodes (P < .001). Although overall survival was not increased in patients who underwent SLNB compared with those who were randomized to observation, patients who underwent SLNB had a significantly increased 5-year disease-free survival rate compared with those who underwent observation alone (78.3% in the biopsy group and 73.1% in the observation group; P = .009). For those with nodal metastases, patients who underwent SLNB and immediate lymphadenectomy had an increased overall 5-year survival rate compared with those who had lymphadenectomy only after presenting with clinically evident disease (72.3% vs 52.4%; P = .004). Moreover, other studies show that for patients with thin melanomas <or= 1.0 mm, the overall survival rate is significantly worse for those with positive SLNs compared to those with negative SLNs. For thin melanomas, Breslow depth >or= 0.76 mm and increased mitotic rate have been shown to be associated with an increased incidence of SLN metastases.

CONCLUSIONS

SLNB provides important prognostic and staging data with minimal morbidity and can be used to identify regional node-negative patients who would not benefit from a complete nodal dissection. In our opinion, SLNB should be performed on most patients (with acceptable surgical and anesthesia risk) who have melanomas with a Breslow depth >or= 0.76 mm.

Meta-analysis of sentinel lymph node positivity in thin melanoma (<or=1 mm)

BACKGROUND

Despite the lack of an established survival benefit of sentinel lymph node (SLN) biopsy, this technique has been increasingly applied in the staging of thin (

METHODS

MEDLINE, EMBASE, and Cochrane databases were searched for rates of SLN positivity in patients with thin melanoma. The methodologic quality of included studies was assessed using the Methodological Index for Non-Randomized Studies criteria. Heterogeneity was assessed using the Cochran Q statistic, and publication bias was examined through funnel plot and the Begg and Mazumdar method. Overall SLN positivity in thin melanoma patients was estimated using the DerSimonial-Laird random effect method.

RESULTS

Thirty-four studies comprising 3651 patients met inclusion criteria. The pooled SLN positivity rate was 5.6%. Significant heterogeneity among studies was detected (P = .005). There was no statistical evidence of publication bias (P = .21). Eighteen studies reported select clinical and histopathologic data limited to SLN-positive patients (n = 113). Among the tumors from these patients, 6.1% were ulcerated, 31.5% demonstrated regression, and 47.5% were Clark level IV/V. Only 4 melanoma-related deaths were reported.

CONCLUSIONS

Relatively few patients with thin melanoma have a positive SLN. To the authors' knowledge, there are no clinical or histopathologic criteria that can reliably identify thin melanoma patients who might benefit from this intervention. Given the increasing diagnosis of thin melanoma, in addition to the cost and potential morbidity of this procedure, alternative strategies to identify patients at risk for lymph node disease are needed.

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Key Words Collapse

MESH Headings

• Clinical Trials as Topic
• Female
• Humans
• Lymph Node Excision
• Lymphatic Metastasis
• Male
• Melanoma/secondary
• Middle Aged
• Mitosis
• Periodicals as Topic
• Sentinel Lymph Node Biopsy
• Skin Neoplasms/pathology

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Grants

• P30 CA016087 NCI NIH HHS
• 5 P30 CA 016087-27 NCI NIH HHS

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Affiliation(s)

Melanie A. Warycha Department of Dermatology, New York University School of Medicine, New York, NY
Jan Zakrzewski Department of Dermatology, New York University School of Medicine, New York, NY
Quanhong Ni Division of Biostatistics and Epidemiology, Department of Public Health, Weill Medical College of Cornell University, New York, NY
Richard L. Shapiro Department of Surgery, New York University School of Medicine, New York, NY
Russell S. Berman Department of Surgery, New York University School of Medicine, New York, NY
Anna C. Pavlick Department of Dermatology, New York University School of Medicine, New York, NY Department of Medicine, New York University School of Medicine, New York, NY
David Polsky Department of Dermatology, New York University School of Medicine, New York, NY Department of Pathology, New York University School of Medicine, New York, NY
Madhu Mazumdar Division of Biostatistics and Epidemiology, Department of Public Health, Weill Medical College of Cornell University, New York, NY
Iman Osman Department of Dermatology, New York University School of Medicine, New York, NY Department of Medicine, New York University School of Medicine, New York, NY

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Solitary dermal melanoma: beginning or end of the metastatic process?

BACKGROUND

Solitary dermal melanoma (SDM) is confined to the dermal and/or subcutaneous tissue without an epidermal component. It is unclear whether this lesion is a subtype of primary melanoma or distant cutaneous metastasis from an unknown primary. We evaluated our large experience to determine the prognosis and optimal management of SDM.

METHODS

Our melanoma referral center's database of prospectively acquired records was used for identification and clinicopathologic analysis of patients presenting with SDM between 1971 and 2005.

RESULTS

Of 12,817 database patients seen during a 34-year period, 101 (0.8%) had SDM. Of 92 patients free of distant metastasis on initial presentation, 55 (60%) were observed and 37 (40%) underwent surgical nodal staging: regional metastases were identified in 7 (19%). Nodal recurrence occurred in 1 of 30 patients (3.3%) with histopathology-negative nodes compared with 13 of 55 patients (24%) who underwent nodal observation instead of nodal staging. Thus, 21 of 92 patients (23%) had nodal metastasis identified during surgical nodal staging or postoperative nodal observation. At a median follow-up of 68 months, estimated 5-year overall survival rate was 73% for 71 patients with localized disease versus 67% for 21 patients with regional disease (P=0.25) versus 22% for 9 patients with distant disease (P=0.009, regional versus distant disease).

CONCLUSIONS

SDM resembles intermediate-thickness primary cutaneous melanoma with respect to prognostic characteristics and clinical evolution, but its rate of distant metastasis justifies radiographic staging and its high rate of regional node metastasis justifies wide excision and sentinel node biopsy.

PET vs sentinel lymph node biopsy for staging melanoma: a patient intervention, comparison, outcome analysis

BACKGROUND

Sentinel lymph node biopsy (SLNB) is the gold standard to assess local lymph nodes in patients with melanoma. Positron emission tomography (PET) has been investigated as a noninvasive alternative to SLNB.

METHODS

A systematic literature review was conducted to evaluate PET and PET/computed tomography (CT) compared with SLNB for staging local lymph nodes in patients with intermediate-risk melanoma using the patient, intervention, comparison, outcome (PICO) search strategy. The PubMed, Medline, CancerLit, and Cochrane Library databases were searched for relevant published materials. Guidelines of the American Society of Clinical Oncology (ASCO), and Cancer Care Ontario (CCO) were reviewed, as was the clinical resource, UpToDate. Studies were classified on the basis of levels of evidence delineated by the Oxford Centre for Evidence-Based Medicine.

RESULTS

The PICO search criteria identified 20 studies. There was no level 1 evidence. There were 7 level 2b articles. One review article was consecutive and thus classified as level 3a evidence. Three review articles were retrieved and categorized as level 3b. Three single-center studies were classified as level 3b, and another 3 were classified as level 4. There were two published letters, considered expert opinion and thus classified as level 5 evidence. All identified papers favored SLNB over PET or PET/CT for identifying occult locoregional lymph node metastases.

CONCLUSION

Despite a lack of high-level evidence, the studies concluded that SLNB is superior to PET for local lymph node staging in patients with intermediate-risk melanoma. National guidelines confirmed these conclusions. The likelihood of PET/CT identifying distant metastases in this patient population is equally low because of the small risk for having distant metastases at diagnosis. Further study is required, including larger multicenter prospective trials.

Absence de valeur prédictive des signes de régression histologique sur l’envahissement du ganglion sentinelle

BACKGROUND

The predictive value of regression in melanoma is debated.

AIM OF THE STUDY

A retrospective single-centre study to evaluate the correlation between regression in primary skin tumor and the presence of micrometastases in sentinel lymph nodes.

PATIENTS AND METHODS

Histological signs of regression in 84 melanomas (>1 mm) with corresponding sentinel lymph nodes were studied by two independent pathologists.

RESULTS

Regression was seen in 40 skin melanoma tumors while micrometastasis was seen in 24. Of the tumors with micrometastasis, only 10 were regressive (RR: 0.47, p=0.49). Breslow value>2 mm and male sex were predictive for node micrometastasis (RR: 4.6, p=0.03 and RR: 7.6, p=0.006, respectively). On multivariate analysis, these two factors were independent.

COMMENTS

These data suggest that regression in primary cutaneous melanoma is not predictive for lymph node metastasis.

Diagnosis and treatment of interval sentinel lymph nodes in patients with cutaneous melanoma

BACKGROUND

Interval sentinel lymph nodes in patients with melanoma are occasionally found outside conventional nodal basins. In this study, the authors examined the frequency, location, and incidence of nodal metastasis of such interval nodes in a large cohort of patients with primary cutaneous melanoma.

METHODS

Between September of 1997 and February of 2003, 374 consecutive patients at the Yale Cancer Center Melanoma Unit underwent sentinel lymph node biopsy for primary cutaneous melanoma with a Breslow thickness of at least 1.0 mm and/or Clark IV or greater histologic dermal invasion. All patients underwent preoperative lymphoscintigraphy to map the lymphatic drainage for the primary lesion and intraoperative confirmation, and biopsy was performed on all sentinel lymph nodes identified.

RESULTS

Unequivocal interval sentinel lymph nodes were identified in eight of 374 patients (2.1 percent). Three of these eight patients had metastatic spread to the interval sentinel nodes. In four of the eight patients, the interval sentinel lymph node was not located in the anticipated lymphatic pathway between the primary tumor and the sentinel lymph node basin.

CONCLUSIONS

Interval sentinel nodes seem as likely to contain micrometastatic disease as those in the expected sentinel lymph node basin. Half of the subjects displayed interval sentinel lymph nodes that were not in the anticipated lymphatic pathway between the primary tumor and the sentinel lymph node basin. These findings suggest that adequate preoperative lymphoscintigraphy and intraoperative recognition of interval nodes are of paramount importance in the treatment of melanoma.

Single-Institution Experience in the Management of Patients with Clinical Stage I and II Cutaneous Melanoma: Results of Sentinel Lymph Node Biopsy in 240 Cases

BACKGROUND

Lymphatic mapping and sentinel lymph node biopsy (SLNB) has been developed as a minimally invasive technique to determine the pathologic status of regional lymph nodes in patients without clinically palpable disease and incorporated in the latest version of the American Joint Committee on Cancer (AJCC) staging system for cutaneous melanoma.

OBJECTIVE

To analyze the results of SLNB and the prognostic value of the micrometastases and the pattern of early recurrences in patients according to sentinel lymph node (SLN) status.

METHOD

Patients with cutaneous melanoma in stages I and II (AJCC 2002) who underwent lymphatic mapping and SLNB from 1997 to 2003 were included in a prospective database for analysis.

RESULTS

The rate of identification of the SLN was 100%. Micrometastases to SLN were found in 20.8% of patients. The rate of SLN micrometastases increased according to Breslow thickness and clinical stage. Breslow thickness of 0.99 mm was the optimal cutpoint for predicting the SLNB result. Twenty-four patients (12.3%) developed a locoregional or distant recurrence at a median follow-up of 31 months. Recurrences were more frequent in patients with a positive SLN. Among patients who had a recurrence, those with a positive SLN were more likely to have distant metastases than those with negative SLN. Nodal recurrences were more frequent in patients with a negative SLN compared with those with a positive SLN.

CONCLUSIONS

The status of the SLN provides accurate staging for identifying patients who may benefit from further therapy and is the most important prognostic factor of relapse-free survival.

Relationship between sentinel lymph node status and regression of primary malignant melanoma

The prognostic significance of spontaneous regression of primary melanoma is a controversial issue. Studies on sentinel lymph node status and circulating tumour cells may represent a step towards a better understanding. The clinical details of 269 melanoma patients who underwent sentinel lymph node biopsy were analysed. Correlation was sought between the parameters of the primary tumour, particularly tumours showing a partial intermediate level of regression, and sentinel lymph node status. The presence of circulating tumour cells was studied by reverse transcription-polymerase chain reaction for tyrosinase messenger RNA preoperatively in 94 patients. Of the examined tumours, 27.8% showed histological features of a partial intermediate level of regression. Regressive tumours were localized predominantly on the trunk (P=0.006), were significantly thinner (P<0.0000) and were less frequently ulcerated (P=0.003) than tumours without regression. Moreover, the majority of regressive melanomas were of the superficial spreading type (P<0.0000) and their sentinel node status was more favourable (P=0.026). We demonstrated the presence of circulating tumour cells in five of 26 (19.2%) regressive and 19 of 68 (29.4%) non-regressive tumours. The difference was not significant (P=0.32). By multivariate analysis, however, the Breslow thickness and ulceration of the primary tumour were predictors of the sentinel lymph node status, in agreement with literature data. A partial intermediate level of regression of the primary tumour did not affect unfavourably the sentinel lymph node status in our study. We failed to demonstrate a significant relationship between the presence of circulating tumour cells and either primary tumour regression or the sentinel lymph node status.

The role of sentinel lymph node biopsy in the management of thin melanoma

The lifetime risk for developing thin (< or =1 mm) melanoma continues to increase steadily. Although generally associated with an excellent prognosis, it also has a proven capacity to metastasize. There has been increasing interest in using sentinel lymph node biopsy to improve staging for thin melanoma. However, it is difficult to define clinicopathologic factors that reliably predict the presence of nodal metastasis. The prognostic significance of a positive sentinel lymph node in thin melanoma remains to be defined.

Pathologic assessment of melanoma sentinel nodes: a role for molecular analysis using quantitative real-time reverse transcription-PCR for MART-1 and tyrosinase messenger RNA

PURPOSE

Molecular analysis of melanoma sentinel nodes (SN) is sensitive, but poorly specific because metastases cannot be distinguished from benign nevus inclusions (BNI). We investigated whether quantitative reverse transcription-PCR (RT-PCR) detection of MART-1 and tyrosinase mRNAs could improve this specificity and contribute to SN assessment.

EXPERIMENTAL DESIGN

Two hundred twenty SNs from 95 melanoma patients analyzed by extensive immunohistopathology and real-time quantitative RT-PCR.

RESULTS

Using histopathology, SNs and patients were allotted to three diagnostic groups: (a) metastasis positive, (b) BNI positive, and (c) melanocyte-free. Median MART-1 and tyrosinase mRNA levels in SNs were significantly different in patients with metastasis compared with patients with BNIs (P < 0.05) and patients without melanocytic lesions (P < 0.001). However, a "gray-zone" was observed where distinction, based on mRNA levels, could not be made between the three groups. For both genes, the highest mRNA level recorded in each RT-PCR-positive patient was positively correlated with Breslow's tumor thickness. For SNs with metastases, tumor burden was significantly correlated to the mRNA level. Using the presence of a MART-1 RT-PCR signal to detect patients with metastases, a sensitivity of 100% and a negative predictive value of 100% were achieved when extensive immunohistology was used as reference.

CONCLUSIONS

Quantitative RT-PCR MART-1 and tyrosinase mRNA analysis cannot be used alone for SN diagnosis because of its poor specificity for melanoma metastasis. However, in approximately one third of cases without RT-PCR evidence of MART-1 expression, extensive histopathologic SN investigation is not necessary, thus substantially reducing the cost of SN analysis. The level of melanocyte-associated mRNA is associated with both tumor thickness and tumor burden as measured histopathologically, suggesting that this may be of prognostic value.

Sentinel lymph node biopsy for cutaneous melanoma of the head and neck

BACKGROUND

Lymph node status is the most important prognostic factor for patients with cutaneous melanoma. Sentinel lymph node biopsy (SLNB) is now the standard of care for staging clinically node-negative patients. It is accurate with low morbidity, yet SLNB for head and neck melanoma is challenging because of unpredictable lymphatic drainage and risk of complications.

METHODS

A retrospective analysis of prospectively collected data identified patients with cutaneous melanoma of the head and neck > or =.76 mm. Sentinel lymph nodes were identified by using a standardized protocol of preoperative lymphoscintigrams, intraoperative blue dye injections, and handheld gamma probes. Clinical, surgical, and pathologic data were collected and analyzed.

RESULTS

A sentinel lymph node was removed in 41 (94%) of 44 patients. Seven (17%) of 41 had at least 1 positive sentinel lymph node. Three of seven had primary tumors <1 mm (two of the three were not ulcerated). The sites of lymphatic drainage of the primary lesion were discordant, with historical anatomically predicted sites in 24.4% of cases. None of the 34 patients with negative SLNB has had a nodal recurrence (false-negative rate, 0%; sensitivity and negative predictive value, 100%). The mean follow-up is 22.4 months (range, <1-69 months). Seven (17%) of 41 patients had minor complications.

CONCLUSIONS

SLNB in the head and neck area is challenging; however, combined preoperative, intraoperative, and histological techniques produce a sensitive procedure with a high negative predictive value. The lack of false-negative results obviates the need for prophylactic neck dissections.

Le diagnostic d’un ganglion tumoral

There are several imaging techniques, each with advantages and limitations. Standard or computed radiography is always useful. CT diagnosis of an enlarged lymph node is easy but it is very difficult to conclude about its reactive or metastatic nature: subtle signs can help. MRI has similar pitfalls but sometimes it may be possible to identify fibrotic scarred nodes. US with Doppler can evaluate the abnormal angioarchitecture of a metastatic lymph node. Sentinel lymph nodes are easily identified by nuclear medicine. CT-PET provides morphologic and metabolic information which increases the diagnostic accuracy. Imaging work-up strategies for selected malignancies are discussed.

Indications for lymphatic mapping and sentinel lymphadenectomy in patients with thin melanoma (Breslow thickness < or =1.0 mm)

BACKGROUND

Patients with thin (Breslow thickness < or =1.0 mm) melanoma have a good prognosis (5-year survival >90%). Consequently, the added benefit of lymphatic mapping and sentinel lymphadenectomy (LM/SL) in these patients is controversial. We hypothesize that LM/SL with a focused examination of the sentinel node (SN) will detect a significant number of SN metastases in patients with thin melanoma and that certain clinical or histopathologic factors may serve as predictors of SN tumor involvement.

METHODS

Over 6 years, 349 patients with melanoma underwent LM/SL and were prospectively entered into an institutional review board (IRB)-approved database. LM/SL was performed with a combined radiotracer and blue dye technique. SNs were serially sectioned, and each section was examined by a dermatopathologist at multiple levels with hematoxylin and eosin as well as immunohistochemical stains.

RESULTS

One hundred forty-six patients (42%) had a melanoma with Breslow thickness < or =1.0 mm; six (4%) of these 146 patients had a tumor-involved SN. On multivariate analysis, none of the clinical or histopathologic factors examined were significantly associated with SN tumor involvement in patients with thin melanoma. Completion lymphadenectomy was performed on all patients with a tumor-involved SN. None of the patients had non-SN tumor involvement.

CONCLUSIONS

The incidence of SN tumor involvement in patients with thin melanoma is considerable. Although we were unable to identify predictors of SN tumor involvement in patients with thin melanoma, efforts to identify predictors of SN tumor involvement should continue. Until better predictors are identified, we continue to advocate offering LM/SL to patients with thin melanomas who demonstrate clinical or histopathologic characteristics that have historically been associated with an increased risk of recurrence and mortality.

Skin cancer screening campaign in the German speaking Community of Belgium

The incidence of primary malignant melanoma (MM) and skin carcinomas, including basal cell carcinoma (BCC) and squamous cell carcinoma (SCC), is progressively raising. As long as their diagnosis and therapeutic managements are initiated early, their prognosis remains favorable. This underlines the importance of early recognition of skin cancers. Furthermore, it has been demonstrated that skin cancer screening programs are efficacious in increasing the population awareness of the early signs of skin cancer and of the dangers of UV - exposure. A skin cancer screening campaign was organised by dermatologists of the German-speaking Community of Belgium in cooperation with the Department of Family, Health, and Social Affairs of the Regional Ministry of the German-speaking Community of Belgium. In order to increase the screening selectivity, two risk populations were targeted; patients presenting 30 or more moles, and patients over 50 years of age presenting recent skin changes of the head and neck area. A media campaign using radio, television and daily press was started to increase the population awareness of the dangers of UV exposure and of the early signs of skin cancer. During 2 screening days, three-hour sessions were organised in 2 health centers located in Eupen and St Vith. A total of 148 patients were examined. A total of 124/148 patients met the selection criteria predefined during the media announcement. The simultaneous presence of 4 dermatologists during the screening sessions allowed a second opinion for warning lesions. Four BBCs as well as 23 patients pesenting dysplastic nevi were clinically diagnosed. During the 2 months following the screening campaign 5 MMs were identified by the same dermatologists in their routine practice. In conclusion, this skin cancer screening campaign led to the diagnosis of 4 carcinomas. The campaign furthermore increased the patient awareness, permitting the diagnosis of 5 MMs during the 2 following months. This figure represents about 30% of all MMs diagnosed yearly in this region of Belgium.

Use of an early-detection strategy to improve disease control in melanoma patients

In order to assess whether early detection might lead to improvement in disease control for patients with melanoma, a rapid access pigmented lesion clinic (PLC) was set up at Mount Vernon Hospital, UK in 1993. Previously we have shown that thinner melanomas were detected via the PLC compared with those presenting prior to its establishment and with those referred via existing routes of referral. The aim of this study was to investigate whether both rates of disease recurrence and disease-free interval were improved via a rapid access PLC. A retrospective case notes audit was performed on three patient groups: those diagnosed with melanoma 1991-1992, those diagnosed via the PLC (1993-1996) and those diagnosed with melanoma through existing routes of referral after establishment of the PLC (1993-1996). There was a significantly improved disease-free interval for patients with regional recurrences diagnosed via the pigmented lesion clinic (PLC) when compared with pre-PLC, non-PLC groups (chi2=13.8487, p=0.0002; chi2=17.0164, p<0.0001, respectively), and when compared with all melanoma patients diagnosed after the establishment of the PLC, irrespective of route of referral (chi2=5.2773, p=0.0216). Local recurrences developed later in patients in the PLC group compared with the pre-PLC group (chi2=6.4883, p=0.0109), and the non-PLC group (chi2=18.49, p<0.0001). In addition there was a reduction in the proportion of regional and local recurrences in the PLC group when compared with the pre-PLC group (chi2=13.92, P<0.001; chi2=2.85, P=0.09 respectively) and non-PLC group (chi2=17.15, P<0.001; chi2=7.73, P=0.005, respectively). These results support the use of rapid access PLCs as a means of improving disease control for melanoma patients.

Standard immunostains for melanoma in sentinel lymph node specimens: which ones are most useful?

BACKGROUND

Sentinel lymph node (SLN) biopsy in melanoma is an increasingly used procedure. Pathologic evaluation of SLNs using immunohistochemistry improves diagnostic accuracy, yet no universally accepted standard protocol for pathologic processing of SLNs exists.

OBJECTIVE

The primary purpose of this study was to evaluate our experience with the sensitivity of the immunostains S-100, HMB-45, and Melan-A for SLN biopsy.

METHODS

Ninety-nine positive SLNs from 72 patients were retrospectively reviewed for the presence of microscopic metastatic melanoma on hematoxylin and eosin (H&E), S-100, HMB-45, and Melan-A stained sections and sensitivities of each immunohistochemical stain were determined.

RESULTS

The sensitivities of S-100, HMB-45, and Melan-A were 97%, 75%, and 96% respectively.

CONCLUSION

Given the lower sensitivity of HMB-45, our practice for evaluation of SLN biopsy specimens was modified using combinations of H&E, S-100, and Melan-A without HMB-45. If the H&E sections are negative or equivocal for metastatic melanoma, immunohistochemistry staining with S-100 protein and Melan-A is performed. New and improved protocols will undoubtedly be forthcoming as the field advances.

Sentinel lymph node detection in primary melanoma with preoperative dynamic lymphoscintigraphy and intraoperative γ probe guidance

Background

This study assessed the value of the radioisotopic method used alone, and factors influencing relapse rates, for sentinel lymph node (SLN) mapping in primary melanoma.

Methods

One hundred and thirty-three patients with a diagnosis of melanoma (thickness greater than 0·75 mm) underwent γ probe-directed lymphatic mapping in a prospective single-centre study.

Results

Mean Breslow thickness was 3 mm. At least one SLN was identified in 132 patients (mean 1·8 nodes per patient); the success rate was 99·2 per cent. Twenty-two patients (16·7 per cent) had a metastasis within the SLN. The mean tumour thickness in patients with a metastatic SLN was 4·4 mm compared with 2·7 mm for patients with a negative SLN (P &lt; 0·001). The median time to recurrence was 20·4 months in SLN-negative patients compared with 8·5 months in those with SLN metastasis (P &lt; 0·001). Ten (9·1 per cent) of the 110 SLN-negative patients developed recurrence. Three patients relapsed in the previously mapped lymphatic basin after a median follow-up of 27·1 months.

Conclusion

This study confirmed the reliability and accuracy of SLN mapping using a radioisotope technique, and also the importance of the SLN as a predictive factor for survival. There was a low risk of locoregional recurrence when the SLN was not involved.

Sentinel lymph node dissection in stage I/II melanoma patients: surgical management and clinical follow-up study

Selective sentinel lymph node (SLN) dissection is widely used in the management of cutaneous melanoma patients without clinical evidence of nodal metastases. A series of 274 consecutive melanoma patients who underwent melanoma primary excision and SLN mapping at our institutions since 1998, and were thereafter followed up and eventually treated, is reported in this prospective study. The aim was to analyse the parameters associated with a higher risk of occult nodal metastases, to evaluate the clinical outcome of melanoma patients who underwent SLN procedure, and to identify by means of multivariate analysis the prognostic parameters with independent predictive value on disease-free survival (DFS) in node-positive and negative patients. The SLN was tumour-negative in 228 patients (83.2%). A disease progression occurred in 25 (10.9%); among them, 10 patients in whom the initially identified SLN had been negative, developed a clinically and histologically evident positive lymph node in the same basin during follow-up. Five-year DFS and overall survival were 75% and 82%, respectively. In 46 patients (16.8%), the SLN proved to be tumour positive. The percentage of SLN-positive patients varied according to the primary thickness, from 11.8% in patients with Breslow of 2 mm or lower, to 34.7% in patients with Breslow from 2 to 4 mm, up to 55.9% in patients with Breslow greater than 4 mm (P<0.001). Only two patients with Breslow thickness lower than 1 mm had positive SLN biopsy. Five-year DFS and overall survival (OS) were 42 and 69%, respectively, significantly lower than those of negative SLN-patients (P<0.001). Multivariate analyses showed that the parameters with prognostic independent value on DFS were SLN status (micrometastases or macrometastases; P=0.0001), and to a lesser extent, Breslow thickness (P=0.04). In conclusion, our data support the clinical usefulness of SLN dissection as a reliable and accurate staging method in patients with cutaneous melanoma. SLN-positive patient OS (5-year survival 69%) seems to be superior to that historically reported for stage III patients treated with curative nodal dissection only after the clinical evidence of palpable adenopathies (5-year survival 36%). The prognostic relevance of the pattern of SLN invasion (micrometastases/macrometastases) could be the basis for the planning of adjuvant treatment trials on selected groups of patients.

Thin melanomas: predictive lethal characteristics from a 30-year clinical experience

OBJECTIVE

To guide treatment and clinical follow-up by defining the natural history of thin melanomas and identifying negative prognostic characteristics that may delineate high-risk patients.

SUMMARY BACKGROUND DATA

In following > 10,000 patients with cutaneous melanoma over the past 30 years, our institution has observed nodal or metastatic disease in approximately 15% of patients with a thin (<1 mm) primary lesion.

METHODS

A database query of patients with cutaneous melanoma returned 1158 patients with primary lesion < or = 1 mm thick and who received their initial treatment at a single institution. Median follow-up was 11 years (range, 1 to 34 years). Patient and melanoma characteristics as well as outcomes were recorded and statistically analyzed.

RESULTS

6.6% of patients had nodal or distant disease at presentation. Over time, an additional 9.4% developed metastases, including nodal and distal recurrences. Overall incidence of advanced disease was 15.3%. Univariate analysis identified male gender (P = 0.01), advanced age (>45 years; P = 0.05), and Breslow thickness (>0.75 mm; P = 0.008) as significant negative prognostic characteristics. Of patients with these 3 high-risk characteristics, 19.7% developed advanced disease (likelihood ratio 6.3; P = 0.007 versus nonhigh-risk patients). This group had more than twice the incidence of nodal recurrences. Patients with recurrence had significantly decreased 10-year survival (82% versus 45%; P < 0.0001). Surprisingly, neither ulceration nor Clark level predicted advanced disease.

CONCLUSIONS

Thin melanomas are potentially lethal lesions. Long-term follow-up identified a high-risk population of older males with tumors between 0.75 mm and 1.0 mm whose risk of recurrent disease approaches 20%. Traditionally accepted negative prognostic factors such as ulceration and discordant Clark levels are not predictive for metastasis in this population. Given the poor prognosis associated with recurrent disease, we recommend close clinical evaluation and follow-up to maximize accurate staging and therapeutic options.

Cost-effectiveness of sentinel lymph node biopsy in thin melanomas

BACKGROUND

Consideration of sentinel lymph node biopsy (SLNB) is recommended for thin melanomas with poor prognostic features; however, few metastases are identified. The purpose of this study was to assess the cost effectiveness of SLNB in this population.

METHODS

The prospective melanoma database was reviewed to identify patients with melanomas <1.2 mm thick who had undergone SLNB. Physician and hospital charges were collected from the appropriate billing department.

RESULTS

A total of 138 patients were identified over an 8-year period (1994-2002). Two patients with positive SLNs were identified (1.4%), one with a melanoma <1 mm thick. Patient charges for SLNB ranged from $10,096 to $15,223 US dollars, compared with $1000 to $1740 US dollars for wide excision as an outpatient. Using these charges, the cost to identify a single positive SLN would be between $696,600 and $1,051,100 US dollars. The cost for wide excision would be between $69,000 and $120,100 US dollars. Assuming that all patients with a positive SLN would die of melanoma, the cost per life saved would be $627,000 to $931,000 US dollars.

CONCLUSIONS

The cost of performing SLNB in this population is great and only a small number will have disease identified that will alter treatment. These data call into question the appropriateness of SLNB for thin melanomas.

Clinical significance of sentinel lymph node involvement in malignant melanoma

In the period 1997-2002, sentinel lymph node (SLN) surgery was performed on 179 primary skin melanoma patients, one to two months after the removal of the primary. Staining with patent blue was combined with an isotope technique. Histological evaluation of the sentinel lymph nodes was performed in serial sections. Immunohistochemical detection of S100, HMB-45, or Melan-A was used in the case of suspected micrometastases. Demonstration of positive sentinel lymph node was followed, preferably within 2-3 weeks, by regional block dissection. In these cases interferon-a2 in low doses or BCG immune therapy were applied as adjuvant therapy. Bimonthly follow-up of the patients included physical examination and the use of imaging techniques as specified in the melanoma protocol. Sentinel lymph node surgery was successful in 177/179 cases (98%). Positive sentinel lymph node was identified in 26/177 patients (14.7%). In node positive patients the thickness of the primary tumour was significantly greater than that of node negative ones (p<0.00001). Patients with micrometastases had significantly poorer symptom-free and overall survival by the Mantel-Cox test than those of the other group (p=0.0001 and p=0.0007 respectively). Comparison of the tumor thickness and positive SLN by discriminance analysis, yielded 81.7% and 79.9%, respectively for correct classification rates. Based on our study and data from the literature, we suggest SLN-positivity as equally strong poor prognosis factor for skin melanoma as the tumor thickness.