Prognostic importance of lymph node tumor burden in melanoma patients staged by sentinel node biopsy

Nonvisualized sentinel node on preoperative lymphoscintigraphy in primary cutaneous melanoma: an 11-year retrospective survey

BACKGROUND

Sentinel lymph node (SLN) biopsy in cutaneous melanoma patients evaluates the regional draining basin for occult micrometastatic disease. Occasionally, nonidentification of SLN impairs the acquisition of this important prognostic factor.

OBJECTIVES

To investigate the outcomes of melanoma patients with negative lymphoscintigraphic findings and patients who underwent SLN biopsy from 2004 to 2015 ( n  = 1200) were retrospectively reviewed for tumor characteristics and clinical outcomes.

METHODS

Patients with nonvisualized lymph nodes (NV group) who underwent only preoperative lymphoscintigraphy were separated and compared with a cohort drawn from all melanoma patients who completed the surgical procedure within the same period (V group).

RESULTS

A negative lymphoscintigraphic scan was observed in 38 cases (3.2% of all patients). The NV group showed a significantly older age (median 66.0 vs. 48.3 years; P  < 0.0001). Head and neck melanomas were more frequent in the NV group compared to the control group (25.1 vs. 7.8%; P  = 0.009). Tumor characteristics such as ulceration and Breslow thickness do not influence the lymphoscintigraphy result. No differences were found in overall survival (OS) and disease-free survival (DFS) between the groups.

CONCLUSIONS

The nonvisualization of regional lymph nodes by lymphoscintigraphy is more frequent in older patients with head and neck melanomas. From the clinical point of view, no specific recommendation emerged for patients' management because the nonvisualization of the SLN did not show a significant influence on DFS and OS rates. However, lack of knowledge of lymph node status suggests performing a tighter follow-up eventually by ultrasound evaluation of all potential lymph node drainage basins.

Sentinel Lymph Node Tumor Burden Using Digital Cell Count Estimation Predicts Outcomes in Melanoma

BACKGROUND

Cutaneous melanoma often metastasizes in primis to sentinel lymph nodes (SLNs). Currently, there is no standardized method of characterizing micrometastatic tumor burden in SLN biopsies for melanoma. Different criteria have been developed to evaluate SLN biopsies, yet none consider the number of cells identified.

AIM

Here, we used software analysis to digitally quantify metastatic tumor burden within SLNs and correlated these data with clinicopathologic and prognostic information.

METHODS

We identified 246 cases of SLN biopsies, including 63 positive (26%) and 183 (74%) negative for metastatic melanoma. Digital cell counting was performed within the greatest metastatic focus and the entire metastatic tumor burden within the same SLN.

RESULTS

Increasing cell count in the largest metastatic deposit correlated with the previously described Rotterdam (Spearman's r = 0.91; 95% CI: 0.84, 0.94), Starz (Spearman's r = 0.78; 95% CI: 0.68, 0.87), and Dewar criteria (p < 0.01), validating our method of using cell count to define SLN tumor burden. Additionally, increasing cell count was associated with decreased metastasis free survival (HR = 2.29; 95% CI: 1.22, 4.31).

CONCLUSION

These data support the use of computerized cell count analysis for prognostication of outcomes in patients undergoing SLN biopsy.

Current management of melanoma patients with nodal metastases

The management of melanoma patients with nodal metastases has undergone dramatic changes over the last decade. In the past, the standard of care for patients with a positive sentinel lymph node biopsy (SLNB) was a completion lymph node dissection (CLND), while patients with palpable macroscopic nodal disease underwent a therapeutic lymphadenectomy in cases with no evidence of systemic spread. However, studies have shown that SLN metastases present as a spectrum of disease, with certain SLN-based factors being prognostic of and correlated with outcomes. Furthermore, the results of key clinical trials demonstrate that CLND provides no survival benefit over nodal observation in positive SLN patients, while other clinical trials have shown that adjuvant immune checkpoint inhibitor therapy or targeted therapy after CLND is associated with a recurrence-free survival benefit. Given the efficacy of these systemic therapies in the adjuvant setting, these agents are now being evaluated and utilized as neoadjuvant treatments in patients with regionally-localized or resectable metastatic melanoma. Multiple options now exist to treat melanoma patients with nodal disease, and determining the best treatment course for a particular case requires an in-depth knowledge of current data and an informed discussion with the patient. This review will provide an overview of the various options for treating melanoma patients with nodal metastases and will discuss the data that supported the development of these treatment options.

Lymphadenectomy after a positive sentinel node biopsy in patients with cutaneous melanoma. A systematic review

Complete lymph node dissection (CLND) following a positive sentinel lymph node biopsy (SLNB) has been the standard treatment for years. However, there is increasing evidence that CLND could be omitted. Approximately 80% of patients with a positive sentinel node biopsy do not have additional nodal involvement; in these contexts, the SLNB could be diagnostic and therapeutic. However, in this group of patients, the therapeutic effect of CLND is unclear.

A systematic search was performed in EMBASE and MEDLINE (PubMed), for studies published between January 1, 2014 and December 31, 2019. Studies were included when they compared immediate CLND and observation after a positive sentinel node. The outcomes of interest were: Overall Survival (OS), melanoma-specific survival (MSS), and disease-free survival (DFS).

Eleven studies met the inclusion criteria. Two randomized clinical trials reported no differences in OS or MSS when complete lymph dissection was compared with observation alone. An increase in regional relapse was observed in the CLND group, and in one randomized controlled trial (RCT) the rate of disease-free survival was superior in those patients.

Most populations in both RCTs had low sentinel lymph node biopsy (SLNB) metastatic deposits, and head and neck melanomas were not included or underrepresented. When CNLD was omitted, an active surveillance protocol was carried out.

The evidence supports that CLND in SLNB positive patients does not confer a survival benefit. Sentinel tumor burden, localization of primary tumor, and feasibility of active surveillance should be taken into account in treatment decisions.

Melanoma: Prognostic Factors and Factors Predictive of Response to Therapy

BACKGROUND

A better understanding of prognostic factors and biomarkers that predict response to treatment is required in order to further improve survival rates in patients with melanoma. Prognostic Factors: The most important histopathological factors prognostic of worse outcomes in melanoma are sentinel lymph node involvement, increased tumor thickness, ulceration and higher mitotic rate. Poorer survival may also be related to several clinical factors, including male gender, older age, axial location of the melanoma, elevated serum levels of lactate dehydrogenase and S100B. Predictive Biomarkers: Several biomarkers have been investigated as being predictive of response to melanoma therapies. For anti-Programmed Death-1(PD-1)/Programmed Death-Ligand 1 (PD-L1) checkpoint inhibitors, PD-L1 tumor expression was initially proposed to have a predictive role in response to anti-PD-1/PD-L1 treatment. However, patients without PD-L1 expression also have a survival benefit with anti-PD-1/PD-L1 therapy, meaning it cannot be used alone to select patients for treatment, in order to affirm that it could be considered a correlative, but not a predictive marker. A range of other factors have shown an association with treatment outcomes and offer potential as predictive biomarkers for immunotherapy, including immune infiltration, chemokine signatures, and tumor mutational load. However, none of these have been clinically validated as a factor for patient selection. For combined targeted therapy (BRAF and MEK inhibition), lactate dehydrogenase level and tumor burden seem to have a role in patient outcomes.

CONCLUSION

With increasing knowledge, the understanding of melanoma stage-specific prognostic features should further improve. Moreover, ongoing trials should provide increasing evidence on the best use of biomarkers to help select the most appropriate patients for tailored treatment with immunotherapies and targeted therapies.

Molecular phenotyping and image-guided surgical treatment of melanoma using spectrally distinct ultrasmall core-shell silica nanoparticles

Accurate detection and quantification of metastases in regional lymph nodes remain a vital prognostic predictor for cancer staging and clinical outcomes. As intratumoral heterogeneity poses a major hurdle to effective treatment planning, more reliable image-guided, cancer-targeted optical multiplexing tools are critically needed in the operative suite. For sentinel lymph node mapping indications, accurately interrogating distinct molecular signatures on cancer cells in vivo with differential levels of sensitivity and specificity remains largely unexplored. To address these challenges and demonstrate sensitivity to detecting micrometastases, we developed batches of spectrally distinct 6-nm near-infrared fluorescent core-shell silica nanoparticles, each batch surface-functionalized with different melanoma targeting ligands. Along with PET imaging, particles accurately detected and molecularly phenotyped cancerous nodes in a spontaneous melanoma miniswine model using image-guided multiplexing tools. Information afforded from these tools offers the potential to not only improve the accuracy of targeted disease removal and patient safety, but to transform surgical decision-making for oncological patients.

Melanoma staging: Evidence-based changes in the American Joint Committee on Cancer eighth edition cancer staging manual

Answer questions and earn CME/CNE To update the melanoma staging system of the American Joint Committee on Cancer (AJCC) a large database was assembled comprising >46,000 patients from 10 centers worldwide with stages I, II, and III melanoma diagnosed since 1998. Based on analyses of this new database, the existing seventh edition AJCC stage IV database, and contemporary clinical trial data, the AJCC Melanoma Expert Panel introduced several important changes to the Tumor, Nodes, Metastasis (TNM) classification and stage grouping criteria. Key changes in the eighth edition AJCC Cancer Staging Manual include: 1) tumor thickness measurements to be recorded to the nearest 0.1 mm, not 0.01 mm; 2) definitions of T1a and T1b are revised (T1a, <0.8 mm without ulceration; T1b, 0.8-1.0 mm with or without ulceration or <0.8 mm with ulceration), with mitotic rate no longer a T category criterion; 3) pathological (but not clinical) stage IA is revised to include T1b N0 M0 (formerly pathologic stage IB); 4) the N category descriptors "microscopic" and "macroscopic" for regional node metastasis are redefined as "clinically occult" and "clinically apparent"; 5) prognostic stage III groupings are based on N category criteria and T category criteria (ie, primary tumor thickness and ulceration) and increased from 3 to 4 subgroups (stages IIIA-IIID); 6) definitions of N subcategories are revised, with the presence of microsatellites, satellites, or in-transit metastases now categorized as N1c, N2c, or N3c based on the number of tumor-involved regional lymph nodes, if any; 7) descriptors are added to each M1 subcategory designation for lactate dehydrogenase (LDH) level (LDH elevation no longer upstages to M1c); and 8) a new M1d designation is added for central nervous system metastases. This evidence-based revision of the AJCC melanoma staging system will guide patient treatment, provide better prognostic estimates, and refine stratification of patients entering clinical trials. CA Cancer J Clin 2017;67:472-492. © 2017 American Cancer Society.

Exhaustive pathologic work-up in sentinel lymph node biopsy for melanoma: is it necessary?

The objective of this study is to determine whether a less exhaustive pathologic work-up to detect melanoma metastasis is clinically useful and does not affect patient prognosis. The success and evolution of the sentinel lymph node (SLN) depends on histological techniques. Several exhaustive protocols of SLN analysis have been published, but are time and cost consuming, with slight increases in the rates of metastasis detection. From 281 patients with SLN biopsy, each SLN was sectioned every 2 mm and from each paraffin block, 2-3 histological sections were evaluated. The patients were divided as follows: the first group (n=185) was subjected to extensive SLN examination (eSLNe) and the second group (n=96) was not subjected to an extensive SLN examination (wSLNe). The average SLN resected was 2 (range: 1-7), evaluating one in 50.9%. The SLN metastasis detection rate was 28.5%, whereas eSLNe increased by 3.2%. During follow-up, 4/26 (17.4%) cases in the wSLNe group showed recurrence in the SLN basin. Factors associated with decreased survival in univariant analysis were recurrence, Breslow thickness, advanced clinical stage, ulceration, and SLN metastasis. eSLNe did not affect disease-specific survival. Multivariate analysis showed recurrence (hazard ratio 23.475, 95% confidence interval: 1903-4559, P<0.001) and Breslow thickness of more than 3.5 mm (hazard ratio 15.222, 95% confidence interval: 1448-3059, P<0.001) as independent risk factors for decreased survival. Our routine for SLN examination enabled an adequate rate of SLN metastasis detection and the eSLNe increased the rate of detection in 3.2%, but did not affect the survival. We did not find any benefit from performing the eSLNe in patients with Breslow thickness less than 3.5 mm.

Micrometastatic cancer cells in lymph nodes, bone marrow, and blood: Clinical significance and biologic implications

Cancer metastasis may be regarded as a progressive process from its inception in the primary tumor microenvironment to distant sites by way of the lymphovascular system. Although this type of tumor dissemination often occurs in an orderly fashion via the sentinel lymph node (SLN), acting as a possible gateway to the regional lymph nodes, bone marrow, and peripheral blood and ultimately to distant metastatic sites, this is not a general rule as tumor cells may enter the blood and spread to distant sites, bypassing the SLN. Methods of detecting micrometastatic cancer cells in the SLN, bone marrow, and peripheral blood of patients have been established. Patients with cancer cells in their SLN, bone marrow, or peripheral blood have worse clinical outcomes than patients with no evidence of spread to these compartments. The presence of these cells also has important biologic implications for disease progression and the clinician's understanding of the process of cancer metastasis. Further characterization of these micrometastatic cancer cells at each stage and site of metastasis is needed to design novel selective therapies for a more "personalized" treatment.

Comparison of sentinel lymph node micrometastatic tumor burden measurements in melanoma

BACKGROUND

Multiple methods have been proposed to classify the micrometastatic tumor burden in sentinel lymph nodes (SLN) for melanoma. The purpose of this study was to determine the classification scheme that best predicts nonsentinel node (NSN) metastasis, disease-free survival (DFS), and overall survival (OS).

STUDY DESIGN

A single reviewer reanalyzed tumor-positive SLN from a multicenter, prospective clinical trial of patients with melanoma ≥ 1.0 mm Breslow thickness who underwent SLN biopsy. The following micrometastatic disease burden measurements were recorded: Starz classification, Dewar classification (microanatomic location), maximum diameter of the largest focus of metastasis, maximum tumor area, and sum of all diameters. Univariate and multivariate models and Kaplan-Meier analysis were used to evaluate each classification system.

RESULTS

We reviewed 204 tumor-positive SLNs from 157 patients. On univariate analysis, all criteria except Starz classification were statistically significant risk factors for NSN metastasis. On multivariate analysis, including Breslow thickness, ulceration, age, sex, and NSN status, maximum diameter (using a cut-off of 3 mm) was the only classification system that was an independent risk factor predicting DFS (hazard ratio 2.31, p = 0.0181) and OS (hazard ratio 3.53, p = 0.0005). By Kaplan-Meier analysis, DFS and OS were significantly different among groups using maximum diameter cut-offs of 1 and 3 mm.

CONCLUSIONS

Maximum tumor diameter outperformed other measurements of metastatic tumor burden, including microanatomic tumor location (Dewar classification), Starz classification, maximum tumor area, and sum of all diameters for prediction of survival. Maximum tumor diameter is a simple method of assessing micrometastatic tumor burden that should be reported routinely.

Tumor volume as a prognostic factor in resectable malignant melanoma

BACKGROUND

Vertical tumor thickness according to Breslow and histological ulceration are still the most powerful predictors for the clinical outcome of resectable cutaneous malignant melanoma (MM) without lymph node infiltration. It has been proposed that tumor volume in MM may also be of prognostic relevance.

METHODS

We retrospectively analyzed the prognostic impact of tumor volume and other established risk factors in 122 MM patients with a median follow-up period of 39.7 months.

RESULTS

We found the logarithmic tumor volume to be a better prognostic factor compared to Breslow tumor thickness in multivariate analysis. MM with a tumor volume below a threshold of 140 mm(3) had a significantly higher relapse-free survival after 5 years of 98% compared to 47% in larger MMs (p < 0.0001).

CONCLUSION

In some melanomas with a low tumor thickness, a higher tumor volume appeared to be linked to a higher risk of disease recurrence. Inclusion of tumor volume into the risk assessment of resectable MM may be of benefit in the future.

Is complete lymph node dissection after a positive sentinel lymph node biopsy for cutaneous melanoma always necessary? A meta-analysis

BACKGROUND

The current recommendation for patients with cutaneous melanoma and a positive sentinel lymph node (SLN) biopsy is a complete lymph node dissection (CLND). However, metastatic melanoma is not present in approximately 80% of CLND specimens. A meta-analysis was performed to identify the clinicopathological variables most predictive of non-sentinel node (NSN) metastases when the sentinel node is positive in patients with melanoma.

METHODS

A systematic search was conducted using MEDLINE, PubMed, EMBASE, Current Contents Connect, Cochrane library, Google scholar, Science Direct, and Web of Science. The search identified 54 relevant articles reporting the frequency of NSN metastases in melanoma. Original data was abstracted from each study and used to calculate a pooled odds ratio (OR) and 95% confidence interval (95% CI).

FINDINGS

The pooled estimates that were found to be significantly associated with the high likelihood of NSN metastases were: ulceration (OR: 1.88, 95% CI: 1.53-2.31), satellitosis (OR: 3.25, 95% CI: 1.86-5.66), neurotropism (OR: 2.51, 95% CI: 1.39-4.53), >1 positive SLN (OR: 1.77, 95% CI: 1.2-2.62), Starz 3 (old) (OR: 1.83, 95% CI: 0.89-3.76), Angiolymphatic invasion (OR: 2.46, 95% CI: 1.34-4.54), extensive location (OR: 2.22, 95% CI: 1.74-2.81), macrometastases >2 mm (OR: 1.95, 95% CI: 1.61-2.35), extranodal extension (OR: 3.38, 95% CI: 1.79-6.40) and capsular involvement (OR: 3.16, 95% CI: 1.37-7.27). There were 3 characteristics not associated with NSN metastases: subcapsular location (OR: 0.51, 95% CI: 0.38-0.67), Rotterdam Criteria <0.1 mm (OR: 0.29, 95% CI: 0.17-0.50) and Starz I (new) (OR: 0.44, 95% CI: 0.22-0.91). Other variables including gender, Breslow thickness 2-4 mm and extremity as primary site were found to be equivocal.

INTERPRETATION

This meta-analysis provides evidence that patients with low SLN tumor burden could probably be spared the morbidity associated with CLND. We identified 9 factors predictive of non-SLN metastases that should be recorded and evaluated routinely in SLN databases. However, further studies are needed to confirm the standard criteria for not performing CLND.

Diversity of stage III melanoma in the era of sentinel lymph node biopsy

BACKGROUND

Sentinel lymph node (SLN) biopsy for melanoma often detects minimal nodal tumor burden. Although all node-positive patients are considered stage III, there is controversy regarding the necessity of adjuvant therapy for all patients with tumor-positive SLN.

METHODS

Post hoc analysis was performed of a prospective multi-institutional study of patients with melanoma ≥ 1.0 mm Breslow thickness. All patients underwent SLN biopsy; completion lymphadenectomy was performed for patients with SLN metastasis. Kaplan-Meier analysis of disease-free survival (DFS) and overall survival (OS) was performed. Univariate and multivariate Cox regression analyses were performed. Classification and regression tree (CART) analysis also was performed.

RESULTS

A total of 509 patients with tumor-positive SLN were evaluated. Independent risk factors for worse OS included thickness, age, gender, presence of ulceration, and tumor-positive non-SLN (nodal metastasis found on completion lymphadenectomy). As the number of tumor-positive SLN and the total number of tumor-positive nodes (SLN and non-SLN) increased, DFS and OS worsened on Kaplan-Meier analysis. On CART analysis, the 5-year OS rates ranged from 84.9% (women with thickness < 2.1 mm, age < 59 years, no ulceration, and tumor-negative non-SLN) to 14.3% (men with thickness ≥ 2.1 mm, age ≥ 59 years, ulceration present, and tumor-positive non-SLN). Six distinct subgroups were identified with 5-year OS in excess of 70%.

CONCLUSIONS

Stage III melanoma in the era of SLN is associated with a very wide range of prognosis. CART analysis of prognostic factors allows discrimination of low-risk subgroups for which adjuvant therapy may not be warranted.

Progression of cutaneous melanoma: implications for treatment

The survival rates of melanoma, like any type of cancer, become worse with advancing stage. Spectrum theory is most consistent with the progression of melanoma from the primary site to the in-transit locations, regional or sentinel lymph nodes and beyond to the distant sites. Therefore, early diagnosis and surgical treatment before its spread is the most effective treatment. Recently, new approaches have revolutionized the diagnosis and treatment of melanoma. Genomic profiling and sequencing will form the basis for molecular taxonomy for more accurate subgrouping of melanoma patients in the future. New insights of molecular mechanisms of metastasis are summarized in this review article. Sentinel lymph node biopsy has become a standard of care for staging primary melanoma without the need for a more morbid complete regional lymph node dissection. With recent developments in molecular biology and genomics, novel molecular targeted therapy is being developed through clinical trials.

Advances in sentinel lymph node mapping for patients with melanoma

Sentinel lymph node mapping allows accurate pathological staging for patients with cutaneous melanoma and clinically normal regional nodes. Early technical advances facilitated its widespread acceptance by surgeons. Morbidity as a result of the procedure is well established, but the potential benefit of providing powerful prognostic information outweighs these risks in most patients with intermediate-risk disease.

The impact of primary melanoma thickness and microscopic tumor burden in sentinel lymph nodes on melanoma patient survival

BACKGROUND

The primary objectives of this work are to (1) quantitate tumor burden in sentinel lymph nodes (SLNs), and (2) assess the independent contributions of SLN tumor burden and primary melanoma thickness (PMT) with respect to progression-free survival (PFS) and overall survival (OS).

METHODS

Sixty-three patients (41 male and 22 female) with one or more positive SLNs were available for review in this study, with median follow-up of 6.8 years. PMT was measured and SLN metastases were assessed for size, as maximum metastasis size (MMS) in mm, by hematoxylin and eosin (H&E) and immunohistochemistry (S100 and HMB45). PFS and OS were calculated from time of SLN resection until melanoma recurrence or death. Univariate and multivariate analyses and trend test were performed.

RESULTS

Kaplan-Meier estimates of PFS and OS differed significantly by MMS (log-rank P = 0.031 for PFS and P = 0.016 for OS) and PMT (log-rank P = 0.036 for PFS and P < 0.001 for OS). After adjusting for age and gender, the hazard ratio (HR) associated with MMS was 1.09 per mm increase (P = 0.05) for PFS, and 6.30 (P = 0.014) and 5.41 (P = 0.048) for OS in patients, respectively, with MMS of 0.6-5.5 mm and MMS ≥5.5 mm compared with those with MMS <0.6 mm. When patients were stratified by their tumor characteristics of PMT, the risk for disease progression and worse OS was substantially higher for the group with PMT ≥ 4.5 mm (HR = 13.10 and P = 0.022 for PFS; HR = 17.26 and P < 0.001 for OS) relative to the baseline group with PMT <1.6 mm. All patients had completion lymph node dissection (CLND) except for four patients. Patients with positive CLND (14, 22.2%) showed significant worse PFS (P = 0.002) and OS (P = 0.0003) than the negative CLND group (45, 71.4%).

CONCLUSIONS

PMT and MMS were independently prognostic of PFS and OS in melanoma patients. Patients with negative CLND had significantly better PFS and OS than those with positive CLND.

Prognosis in patients with sentinel node-positive melanoma is accurately defined by the combined Rotterdam tumor load and Dewar topography criteria

PURPOSE

Prognosis in patients with sentinel node (SN)-positive melanoma correlates with several characteristics of the metastases in the SN such as size and site. These factors reflect biologic behavior and may separate out patients who may or may not need additional locoregional and/or systemic therapy.

PATIENTS AND METHODS

Between 1993 and 2008, 1,080 patients (509 women and 571 men) were diagnosed with tumor burden in the SN in nine European Organisation for Research and Treatment of Cancer (EORTC) melanoma group centers. In total, 1,009 patients (93%) underwent completion lymph node dissection (CLND). Median Breslow thickness was 3.00 mm. The median follow-up time was 37 months. Tumor load and tumor site were reclassified in all nodes by the Rotterdam criteria for size and in 88% by the Dewar criteria for topography.

RESULTS

Patients with submicrometastases (< 0.1 mm in diameter) were shown to have an estimated 5-year overall survival rate of 91% and a low nonsentinel node (NSN) positivity rate of 9%. This is comparable to the rate in SN-negative patients. The strongest predictive parameter for NSN positivity and prognostic parameter for survival was the Rotterdam-Dewar Combined (RDC) criteria. Patients with submicrometastases that were present in the subcapsular area only, had an NSN positivity rate of 2% and an estimated 5- and 10-year melanoma-specific survival (MSS) of 95%.

CONCLUSION

Patients with metastases < 0.1 mm, especially when present in the subcapsular area only, may be overtreated by a routine CLND and have an MSS that is indistinguishable from that of SN-negative patients. Thus the RDC criteria provide a rational basis for decision making in the absence of conclusions provided by randomized controlled trials.

Importance of tumor load in the sentinel node in melanoma: clinical dilemmas

There are two hypotheses to explain melanoma dissemination: first, simultaneous lymphatic and hematogeneous spread, with regional lymph nodes as indicators of metastatic disease; and second, orderly progression, with regional lymph nodes as governors of metastatic disease. The sentinel node (SN) has been defined as the first draining lymph node from a tumor and is harvested with the use of the triple technique and is processed by an extensive pathology protocol. The SN status is a strong prognostic factor for survival (83-94% for SN negative, 56-75% SN-positive patients). False-negative rates are considerable (9-21%). Preliminary results of the MSLT-1 trial did not demonstrate a survival benefit for the SN procedure, although a subgroup analysis indicates a possible benefit. A mathematical model has demonstrated 24% prognostic false positivity. SN tumor burden represents a heterogeneous patient population and is classified most frequently with the Starz, Dewar or Rotterdam Criteria. A completion lymph-node dissection might not be indicated in all SN-positive patients. Patients classified with metastases <0.1 mm by the Rotterdam Criteria have excellent survival rates. Ultrasound-guided fine-needle aspiration cytology is emerging as a staging tool for high-risk patients, but more research is necessary before this can change clinical practice.

Metastatic outgrowth encompasses COL-I, FN1, and POSTN up-regulation and assembly to fibrillar networks regulating cell adhesion, migration, and growth

Although the outgrowth of micrometastases into macrometastases is the rate-limiting step in metastatic progression and the main determinant of cancer fatality, the molecular mechanisms involved have been little studied. Here, we compared the gene expression profiles of melanoma lymph node micro- and macrometastases and unexpectedly found no common up-regulation of any single growth factor/cytokine, except for the cytokine-like SPP1. Importantly, metastatic outgrowth was found to be consistently associated with activation of the transforming growth factor-beta signaling pathway (confirmed by phospho-SMAD2 staining) and concerted up-regulation of POSTN, FN1, COL-I, and VCAN genes-all inducible by transforming growth factor-beta. The encoded extracellular matrix proteins were found to together form intricate fibrillar networks around tumor cell nests in melanoma and breast cancer metastases from various organs. Functional analyses suggested that these newly synthesized protein networks regulate adhesion, migration, and growth of tumor cells, fibroblasts, and endothelial cells. POSTN acted as an anti-adhesive molecule counteracting the adhesive functions of FN1 and COL-I. Further, cellular FN and POSTN were specifically overexpressed in the newly forming/formed tumor blood vessels. Transforming growth factor-beta receptors and the metastasis-related matrix proteins, POSTN and FN1, in particular, may thus provide attractive targets for development of new therapies against disseminated melanoma, breast cancer, and possibly other tumors, by affecting key processes of metastasis: tumor/stromal cell migration, growth, and angiogenesis.

[Suspicious eyelid spots]

Flat lesions of the eyelids are in most cases related to precancerous skin lesions or malignant tumors of the eyelids. Rarely, the following diagnoses can be established: alkaptonuria, Addison disease, argyrosis, or toxicity to systemic medications.

Influence of sentinel lymph node tumor burden on survival in melanoma

BACKGROUND

Completion lymph node dissection (CLND) is the standard procedure for patients with positive sentinel lymph nodes (SLN). With extensive pathological workup, increased numbers of small metastatic deposits are detected in SLN. This study evaluated the prognostic significance of SLN metastatic deposits < or = 0.2 mm in patients treated in a referral cancer center in Brazil.

METHODS

Patients with stage I/II melanoma, consecutively submitted to a SLN procedure by the same surgeon from 2000 to 2006, were evaluated. All positive SLN and randomly selected negative cases were reviewed by two pathologists. Different prognostic factors and SLN tumor burden were recorded. Additional positive non-SLN after CLND, and disease outcome were evaluated.

RESULTS

Of 381 patients who underwent SLN biopsy, 103 (27%) were positive. The mean/median Breslow tumor thickness in the overall group was 3.4/2.0 mm and in the SLN positive patients was 5.72/4.0 mm. Among these patients, 48 (47%) had metastatic deposits >2 mm (macrometastasis), 49 (47%) had metastatic deposits < or =2 mm but >0.2 mm (micrometastasis), and 6 (6%) had metastatic deposits < or =0.2 mm (submicrometastasis). Additional positive non-SLN were detected in 29% of patients with macrometastasis, in 25% of patients with micrometastasis, and in 0% of patients with submicrometastases. At median follow-up of 35 months, the estimated 3-year overall survival was 92% for negative SLN, 64% for micrometastases, 53% for macrometastases, and 100% for submicrometastases (P < 0.001).

CONCLUSION

In the present study, patients with SLN metastatic deposits < or =0.2 mm had no additional positive non-SLNs, and no recurrences or deaths were recorded, suggesting that their prognosis is equivalent to that of patients with negative SLN.

Interobserver reproducibility of histologic parameters of melanoma deposits in sentinel lymph nodes: implications for management of patients with melanoma

BACKGROUND

: Histologic parameters of melanoma deposits in sentinel lymph nodes (SLNs) have been shown to be predictive of clinical outcome and the presence or absence of tumor in non-SLNs, but assessment of these parameters is prone to interobserver variation.

METHODS

: Histologic sections of 44 SLNs containing metastatic melanoma were examined by 7 pathologists. Parameters assessed included cross-sectional area of tumor deposits, cross-sectional area of SLNs, percentage of SLN area involved by tumor calculated from the 2 previous parameters, estimated percentage of SLN area involved by tumor, tumor penetrative depth, location of tumor within the SLN, and presence of extracapsular spread. Levels of interobserver agreement were measured by using intraclass correlation coefficients (ICC).

RESULTS

: There was good to excellent interobserver agreement on measurement of quantitative parameters: maximal size of largest tumor deposits, calculated area of 3 largest tumor deposits, percentage of the area of SLN involved by tumor, and tumor penetrative depth (ICC, 0.88, 0.73, 0.68, and 0.83, respectively). There was moderate agreement on the evaluation of subcapsular versus nonsubcapsular location of tumor deposits (ICC = 0.50). Agreement on assessment of extracapsular spread was fair (ICC = 0.39).

CONCLUSIONS

: Assessment of some of the quantitative parameters was highly reproducible between pathologists. However, evaluation of the location of tumor deposits within SLNs and assessment of extracapsular spread was less reproducible. Clearer definitions and training can be expected to improve the reproducibility of assessment. These results have important implications for reliability and reproducibility of these parameters in staging, prediction of outcome, and clinical management of melanoma patients. Cancer 2009. (c) 2009 American Cancer Society.

Sentinel node biopsy for skin melanoma

BACKGROUND/AIM

Skin melanoma is one of the most malignant diseases with increasing incidence rate. Sentinel node biopsy (SNB) is very important for early detection of metastatic spread. The aim of the study was to analyze the first 40 patients with skin melanoma of 1 to 4 mm Breslow thickness when SNB was indicated.

METHODS

The patient characteristics, localization of the primary melanoma as well as histology grade were analyzed. SNB with intraoperative radiocolloid and methylene blue dye detection was performed.

RESULTS

Complication rate after SNB was analyzed and seroma was found in 5% of the patients. The therapeutic node dissection was performed in 10 patients with positive sentinel biopsy. The follow-up lasted two years. In five patients the false negative SNB was defined after the mean time of 11 months and the therapeutic dissection was performed.

CONCLUSION

SNB in melanoma patients is a useful diagnostic procedure. It is advised for melanoma of 1 to 4 mm Breslow thickness.

Expert opinion in melanoma: the sentinel node; EORTC Melanoma Group recommendations on practical methodology of the measurement of the microanatomic location of metastases and metastatic tumour burden

The sentinel node (SN) status has been recognised to be the most important prognostic factor in melanoma. Many studies have investigated additional factors to further predict survival/lymph node involvement. The EORTC Melanoma Group (MG) has formulated the following question: How should we report the microanatomic location and SN tumour burden? The EORTC MG recommends the following: the EORTC MG SN pathology protocol or a similarly extensive protocol, which has also been proven to be accurate, should be used. Only measure what you can see not what you presume. Cumulative measurements decrease the accuracy and reproducibility of measuring. The most reproducible measure is a single measurement of the maximum diameter of the largest lesion in any direction (1-D). If there is any infiltration into the parenchyma, this lesion can no longer be considered solely subcapsular. Reporting of the microanatomic location of metastases should be an assessment of the entire sentinel node, not only of the largest lesion. Multifocality reflects a scattered metastatic pattern, not to be confused with multiple cohesive foci, which fall under the regular location system. A subcapsular metastasis should have a smooth usually curved outline, not ragged or irregular. We recommend all pathologists to report the following items per positive SN for melanoma patients: the microanatomic location of the metastases according to Dewar et al. for the entire node, the SN Tumour Burden according to the Rotterdam Criteria for the maximum diameter of the largest metastasis expressed as an absolute number, and the SN Tumour Burden stratified per category; <0.1mm or 0.1-1.0mm or >1.0mm.

Surgical management of melanoma

Melanoma is an increasing health care problem worldwide. Up to 80,000 cases of melanoma are diagnosed per year and it is the sixth leading cause of cancer death in the United States. The lifetime risk is estimated to be 1 in 75 individuals for the development of melanoma. Surgery remains the mainstay of treatment of melanoma, and in most cases it is curative. Several important surgical issues are discussed in this review, including the extent of surgical margins, Mohs micrographic surgery for melanoma in situ, the use of sentinel lymph node biopsy, the usefulness of lymphadenectomy, isolated limb perfusion, and the role of metastasectomy.

Positive nonsentinel node status predicts mortality in patients with cutaneous melanoma

While sentinel lymph node biopsy (SLN) is a highly accurate and well-tolerated procedure for patients with cutaneous melanoma, the role of the completion lymph node dissection (CLND) for patients with positive SLN biopsy remains unknown. This study aimed to look at the prognostic value of a positive nonsentinel lymph node (NSLN). A prospectively maintained database identified 222 patients with cutaneous melanoma and a positive SLN biopsy, without evidence of distant disease. All of these patients underwent CLND, and 37 patients (17%) had positive NSLN. With median follow-up of 33 months, patients with negative NSLN had median survival of 104 months, while patients with positive NSLN had median survival of 36 months (p < 0.001). There were no survivors in the patients with positive NSLN beyond 6 years. When patients with an equal number of positive nodes were analyzed, the presence of a positive NSLN was still associated with worse melanoma-specific survival (66 months for NSLN- versus 34 months for NSLN+, p = 0.04). While increasing age, tumor thickness, and male sex were associated with an increased risk of death on multivariate analysis, a positive NSLN was the most important predictor of survival (hazard ratio 2.5). We conclude that positive NSLN is an independent predictor of disease-specific survival in patients with cutaneous melanoma.

False-positive cells in sentinel lymph nodes

Melanoma sentinel lymph nodes (SLN) are carefully evaluated to maximize sensitivity. Examination includes hematoxylin and eosin (H+E) stained sections at multiple levels through the node, with subsequent immunohistochemical (IHC) stains for melanocytic markers if H+E sections are negative for melanoma. However, not all IHC-positive cells in SLN are metastatic melanoma, as evidenced by the presence of MART-1 positive cells in SLN from breast cancer patients with no history of melanoma (so-called 'false-positive' cells). These 'false-positive cells' could be nodal nevus, non-melanocytic cells with cross-reacting antigenic determinants, phagocytic cells containing melanocyte antigens, or possibly melanocytes or melanocyte stem cells liberated at the time of biopsy of the cutaneous melanoma. Examination of SLN requires careful correlation of H+E and IHC findings.

Microscopic tumor burden in sentinel lymph nodes predicts synchronous nonsentinel lymph node involvement in patients with melanoma

PURPOSE

We and others have demonstrated that additional positive lymph nodes (LNs) are identified in only 8% to 33% of patients with melanoma who have positive sentinel LNs (SLNs) and undergo complete therapeutic LN dissection (cTLND). We sought to determine predictors of additional regional LN involvement in patients with positive SLNs.

PATIENTS AND METHODS

Patients with clinically node-negative melanoma who underwent SLN biopsy (1991 to 2003) and had positive SLNs were identified. Clinicopathologic factors, including extent of microscopic disease within SLNs, were evaluated as potential predictors of positive non-SLNs.

RESULTS

Overall, 359 (16.3%) of the 2,203 patients identified had a positive SLN. Positive non-SLNs were identified in 48 (14.0%) of the 343 patients with positive SLNs who underwent cTLND. On univariate analysis, several measures of SLN microscopic tumor burden, one versus three or more SLNs harvested, tumor thickness more than 2 mm, age older than 50 years, and Clark level higher than III were predictive of positive non-SLNs; primary tumor ulceration and number of positive SLNs had no apparent impact. On multivariable logistic regression analysis, measures of SLN microscopic tumor burden were the most significant independent predictors of positive non-SLNs; tumor thickness more than 2 mm and number of SLNs harvested also predicted additional disease. A model was developed that stratified patients according to their risk for non-SLN involvement.

CONCLUSION

In melanoma patients with positive SLNs, SLN tumor burden, primary tumor thickness, and number of SLNs harvested may be useful in identifying a group at low risk for positive non-SLNs and be spared the potential morbidity of a cTLND.

The influence of sentinel lymph node tumour burden on additional lymph node involvement and disease-free survival in cutaneous melanoma--a retrospective analysis of 392 cases

Twenty per cent of sentinel lymph node (SLN)-positive melanoma patients have positive non-SLN lymph nodes in completion lymph node dissection (CLND). We investigated SLN tumour load, non-sentinel positivity and disease-free survival (DFS) to assess whether certain patients could be spared CLND. Sentinel lymph node biopsy was performed on 392 patients between 1999 and 2005. Median observation period was 38.8 months. Sentinel lymph node tumour load did not predict non-SLN positivity: 30.8% of patients with SLN macrometastases (> or =2 mm) and 16.4% with micrometastases (< or =2 mm) had non-SLN positivity (P=0.09). Tumour recurrences after positive SLNs were more than twice as frequent for SLN macrometastases (51.3%) than for micrometastases (24.6%) (P=0.005). For patients with SLN micrometastases, the DFS analysis was worse (P=0.003) when comparing those with positive non-SLNs (60% recurrences) to those without (17.6% recurrences). This difference did not translate into significant differences in DFS: patients with SLN micrometastasis, either with (P=0.022) or without additional positive non-SLNs (P<0.0001), fared worse than patients with tumour-free SLNs. The 2-mm cutoff for SLN tumour load accurately predicts differences in DFS. Non-SLN positivity in CLND, however, cannot be predicted. Therefore, contrary to other studies, no recommendations concerning discontinuation of CLND based on SLN tumour load can be deduced.

Factors predictive of nonsentinel lymph node involvement and clinical outcome in melanoma patients with metastatic sentinel lymph node

BACKGROUND

Identification of melanoma patients who need completion lymphadenectomy and adjuvant treatment after positive sentinel lymph node (SLN) biopsy would be a fundamental step forward toward personalized medicine. This study tested the hypothesis that the microscopic features of metastatic SLNs might predict not only nonsentinel lymph node (NSLN) status, but also patients' clinical outcomes.

METHODS

A retrospective analysis was performed on 96 consecutive melanoma patients who underwent completion lymphadenectomy after positive SLN biopsy. Patients' age and sex, primary tumor Breslow thickness, number of positive SLNs, the largest diameter and depth of invasion of metastatic deposits in the SLN, S stage, and pattern of nodal involvement were correlated with the presence of metastatic disease in NSLNs as well as with the likelihood of tumor recurrence and patient death.

RESULTS

At pathological examination, 20 patients (20.8%) had metastatic melanoma in the NSLN. Pattern of nodal involvement, depth of invasion of SLN by metastatic disease, and S stage were statistically significantly associated with the presence of metastatic disease in NSLN. Multivariate analysis revealed that only the SLN depth of invasion was an independent predictor of NSLN status (P = .0035). This parameter was also significantly associated with disease-free and overall survival, both by univariate (P < .0001 and P = .0006, respectively) and multivariate (P < .0001 and P = .0013, respectively) survival analysis.

CONCLUSIONS

These findings support further investigation of SLN depth of invasion as a predictive factor of potential clinical use to select patients as candidates for completion lymphadenectomy and adjuvant treatment.