Thin primary cutaneous malignant melanoma: a prognostic tree for 10-year metastasis is more accurate than American Joint Committee on Cancer staging

Gene expression profiles of human melanoma cells with different invasive potential reveal TSPAN8 as a novel mediator of invasion

Background:

Metastatic melanoma requires early detection, being treatment resistant. However, the earliest events of melanoma metastasis, and especially of dermal invasion, remain ill defined.

Results and methods:

Gene expression profiles of two clonal subpopulations, selected from the same human melanoma cell line, but differing in ability to cross the dermal–epidermal junction in skin reconstructs, were compared by oligonucleotide microarray. Of 26 496 cDNA probes, 461 were differentially expressed (>2-fold; P< 0.001), only 71 genes being upregulated in invasive cells. Among them, TSPAN8, a tetraspanin not yet described in melanoma, was upregulated at mRNA and protein levels in melanoma cells from the invasive clone, as assessed by RT–PCR, flow cytometry and western blot analysis. Interestingly, TSPAN8 was the only tetraspanin in which overexpression correlated with invasive phenotype. Flow cytometry of well-defined melanoma cell lines confirmed that TSPAN8 was exclusively expressed by invasive, but not non-invasive melanoma cells or normal melanocytes. Immunohistochemistry revealed that TSPAN8 was expressed by melanoma cells in primary melanomas and metastases, but not epidermal cells in healthy skin. The functional role of TSPAN8 was demonstrated by silencing endogenous TSPAN8 with siRNA, reducing invasive outgrowth from tumour spheroids within matrigel without affecting cell proliferation or survival.

Conclusion:

TSPAN8 expression may enable melanoma cells to cross the cutaneous basement membrane, leading to dermal invasion and progression to metastasis. TSPAN8 could be a promising target in early detection and treatment of melanoma.

B16 melanoma secretomes and in vitro invasiveness: syntenin as an invasion modulator

To characterize proteins involved in melanoma dissemination, protein profiles from B16F10 and B16Bl6 cells were compared, as only B16Bl6 cells give pulmonary metastases after subcutaneous graft. As B16F10 and B16Bl6 cells had the same invasive capacities in vitro, we wondered whether their extracellular content could be different and correlate with their metastatic properties. We have shown that B16F10 and B16Bl6 culture cell supernatants have different modulatory effects on HT1080 fibrosarcoma cell invasion in Matrigel-coated chambers. B16Bl6 supernatants significantly enhanced HT1080 in vitro invasion as compared with B16F10 ones, suggesting differences in their protein profiles. Indeed, proteomic analysis allowed the identification of 18 differential proteins. Among the proteins with a higher concentration in B16Bl6 supernanants, lactate dehydrogenase B, M2 pyruvate kinase, cathepsin D, and galectin 1 were involved in the melanoma aggressiveness signature. Interestingly, several Gag retroviral proteins, as well as syntenin, were found mainly in the B16F10 secretome. Although its intracellular form is known as an aggressive melanoma marker, we show for the first time that syntenin was actively secreted and could reduce the invasion process, probably by protein interactions in the B16 model.

Sentinel lymph node biopsy and melanoma: 2010 update Part II

This article will discuss the evidence for and against the therapeutic efficacy of early removal of potentially affected lymph nodes, morbidity associated with sentinel lymph node biopsy and completion lymphadenectomy, current guidelines regarding patient selection for sentinel lymph node biopsy, and the remaining questions that ongoing clinical trials are attempting to answer. The Sunbelt Melanoma Trial and the Multicenter Selective Lymphadenectomy Trials I and II will be discussed in detail.

LEARNING OBJECTIVES

At the completion of this learning activity, participants should be able to discuss the data regarding early surgical removal of lymph nodes and its effect on the overall survival of melanoma patients, be able to discuss the potential benefits and morbidity associated with complete lymph node dissection, and to summarize the ongoing trials aimed at addressing the question of therapeutic value of early surgical treatment of regional lymph nodes that may contain micrometastases.

Predictors of occult nodal metastasis in patients with thin melanoma

HYPOTHESIS

Thin primary lesions are largely responsible for the rapid increase in melanoma incidence, making identification of appropriate candidates for nodal staging in this group critically important. We hypothesized that common clinical variables may accurately estimate the risk of nodal metastasis after wide excision and determine the need for sentinel node biopsy.

DESIGN

Review of prospectively acquired data in a large melanoma database.

SETTING

A tertiary referral center.

PATIENTS

A total of 2211 patients with thin melanoma treated by wide local excision alone were identified in the database between January 1, 1971, and December 31, 2005. Of those, 1732 met entry criteria.

MAIN OUTCOME MEASURES

We examined the rate of regional nodal recurrence and the impact of clinical and demographic variables by univariate and multivariate analyses.

RESULTS

The overall nodal recurrence rate was 2.9%; median time to recurrence was 38.3 months. Univariate analysis of 1732 patients identified male sex (P < .001), increased Breslow thickness (P < .001), and increased Clark level (P < .001) as significant for nodal recurrence. Multivariate analysis identified male sex (hazard ratio, 3.5; 95% confidence interval, 1.8-7.0; P < .001), younger age (0.45; 0.24-0.86; P = .001), and increased Breslow thickness (2.5; 1.6-3.7; categorical P < .001) as significant for nodal recurrence. The Clark level was no longer significant (P = .63). Breslow thickness, age, and sex were used to develop a scoring system and nomogram for the risk of nodal involvement. Predictions ranged from 0.1% in the lowest-risk group to 17.4% in the highest-risk group.

CONCLUSIONS

Many patients with thin melanoma will have nodal recurrence after wide excision alone. Three simple clinical variables may be used to estimate recurrence risk and select patients for sentinel node biopsy.

[Tumour regression is not predictive for higher risk of sentinel node involvement in thin melanomas (Breslow thickness < or = 1 mm)]

BACKGROUND

Thin melanomas (Breslow thickness < or = 1 mm) are considered highly curable. The aim of this study was to evaluate the correlation between histological tumour regression and sentinel lymph node (SLN) involvement in thin melanomas.

PATIENTS AND METHODS

This was a retrospective single-centre study of 34 patients with thin melanomas undergoing SLN biopsy between April 1998 and January 2005.

RESULTS

The study included 14 women and 20 men of mean age 56.3 years. Melanomas were located on the neck (n=3), soles (n=4), trunk (n=13) and extremities (n=14). Pathological examination showed 25 SSM, four acral lentiginous melanomas, three in situ melanomas, one nodular melanoma and one unclassified melanoma with a mean Breslow thickness of 0.57 mm. Histological tumour regression was observed in 26 over 34 cases and ulceration was found in one case. Clark levels were as follows: I (n=3), II (n=20), III (n=9), IV (n=2). Growth phase was available in 15 cases (seven radial and eight vertical). Mitotic rates, available in 24 cases, were: 0 (n=9), 1 (n=11), 2 (n=2), 3 (n=1), 6 (n=1). One patient with histological tumour regression (2.9% of cases and 3.8% of cases with regressing tumours) had a metastatic SLN. One patient negative for SLN had a lung relapse and died of the disease. Mean follow-up was 26.2 months.

CONCLUSION

The results of the present study and the analysis of the literature show that histological regression of the primary tumour does not seem predictive of higher risk of SLN involvement in thin melanomas. This suggests that screening for SLN is not indicated in thin melanomas, even those with histological regression.

Progress in melanoma histopathology and diagnosis

This article reviews the main aspects of the histopathology of cutaneous melanoma with emphasis on recent advances in the morphological evaluation of these lesions. The limitations of morphology for the "so called" borderline lesions are briefly discussed, with a list of diagnostic criteria to help predict behavior for these challenging lesions. The prognostic factors are described with emphasis on the ones that are currently being used by the American Joint Committee on Cancer staging system. Ancillary tests, such as immunohistochemistry and molecular techniques, are also briefly touched upon as complimentary tools to help understand the biology of malignant melanoma. The conclusion is that an accurate morphological evaluation remains the most efficient approach to establish the diagnosis and predict behavior of this challenging neoplasm.

The classification of cutaneous melanoma

Forty years ago, a clinical and histological classification scheme and prognostic factors were described for cutaneous melanoma. This scheme included the subtypes superficial spreading, nodular and lentigo maligna, and prognostic factors including tumor thickness, ulceration, and mitotic activity. There have been some tweaks to the classification scheme, but these basic findings form the foundation for melanoma diagnosis and staging today. Currently, no molecular marker or target has proved reliably useful in the staging or treatment of melanoma. Measurement with a simple ruler serves as the basis for the staging of primary cutaneous melanoma, while the recognition of primary tumor mitotic activity and ulceration also remain significant factors. Recently, mutational analysis has revealed a correlation of activating mutations with the morphological descriptors from decades ago. Future classification schemes may have more power in predicting response to therapy by integrating specific genomic and intra-tumoral expression profiles with histologic findings.

Melanoma prognostic factors found in the dermatopathology report

Significant prognostic information is available in a routine melanoma dermatopathology report. Features that are enumerated in the pathology report and that portend a potentially poorer prognosis are older age, site (acral, head, neck), male sex, increasing Breslow tumor thickness, increasing Clark's level, ulceration, increasing number of mitoses, vertical growth phase, regression, absence of a host inflammatory response, increased tumor vascularity, angiotropism, vascular invasion, neurotropism, marked atypia, and satellite metastasis.

Tissue biomarkers for prognosis in cutaneous melanoma: a systematic review and meta-analysis

In the clinical management of early-stage cutaneous melanoma, it is critical to determine which patients are cured by surgery alone and which should be treated with adjuvant therapy. To assist in this decision, many groups have made an effort to use molecular information. However, although there are hundreds of studies that have sought to assess the potential prognostic value of molecular markers in predicting the course of cutaneous melanoma, at this time, no molecular method to improve risk stratification is part of recommended clinical practice. To help understand this disconnect, we conducted a systematic review and meta-analysis of the published literature that reported immunohistochemistry-based protein biomarkers of melanoma outcome. Three parallel search strategies were applied to the PubMed database through January 15, 2008, to identify cohort studies that reported associations between immunohistochemical expression and survival outcomes in melanoma that conformed to the REMARK criteria. Of the 102 cohort studies, we identified only 37 manuscripts, collectively describing 87 assays on 62 distinct proteins, which met all inclusion criteria. Promising markers that emerged included melanoma cell adhesion molecule (MCAM)/MUC18 (all-cause mortality [ACM] hazard ratio [HR] = 16.34; 95% confidence interval [CI] = 3.80 to 70.28), matrix metalloproteinase-2 (melanoma-specific mortality [MSM] HR = 2.6; 95% CI = 1.32 to 5.07), Ki-67 (combined ACM HR = 2.66; 95% CI = 1.41 to 5.01), proliferating cell nuclear antigen (ACM HR = 2.27; 95% CI = 1.56 to 3.31), and p16/INK4A (ACM HR = 0.29; 95% CI = 0.10 to 0.83, MSM HR = 0.4; 95% CI = 0.24 to 0.67). We further noted incomplete adherence to the REMARK guidelines: 14 of 27 cohort studies that failed to adequately report their methods and nine studies that failed to either perform multivariable analyses or report their risk estimates were published since 2005.

Stage-specific outcomes of patients with uterine leiomyosarcoma: a comparison of the international Federation of gynecology and obstetrics and american joint committee on cancer staging systems

PURPOSE

Uterine leiomyosarcoma (LMS) is staged by the modified International Federation of Gynecology and Obstetrics (FIGO) staging system for uterine cancer. We aimed to determine whether the American Joint Committee on Cancer (AJCC) soft tissue sarcoma (STS) staging system is more accurate in predicting progression-free survival (PFS) and overall survival (OS).

PATIENTS AND METHODS

Patients with uterine LMS who presented at our institution from 1982 to 2005 were staged retrospectively according to a modified FIGO staging system and the AJCC STS staging system. The predictive accuracy of the two staging systems was compared using concordance estimation.

RESULTS

Two hundred nineteen patients had sufficient clinical and pathologic information to be staged under both systems; 132 patients were upstaged using the AJCC staging system, whereas only four were downstaged. Stage-specific PFS and OS rates for stages I, II, and III differed substantially between the two staging systems. In both systems, there was prognostic overlap between stages II and III. Thus, despite the marked stage-specific differences in 5-year PFS and OS rates for stages I, II, and III, both systems had similar concordance indices.

CONCLUSION

Estimates of stage-specific PFS and OS for uterine LMS were altered substantially when using the AJCC versus FIGO staging system. Adjuvant treatment strategies should be tested in patients at substantial risk for disease progression and death. Neither the FIGO nor AJCC staging system is ideal for identifying such patients, suggesting a need for a uterine LMS-specific staging system to better target patients for trials of adjuvant therapies.

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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Importance of sentinel lymph node biopsy in patients with thin melanoma

HYPOTHESIS

The status of the sentinel node (SN) confers important prognostic information for patients with thin melanoma.

DESIGN, SETTING, AND PATIENTS

We queried our melanoma database to identify patients undergoing sentinel lymph node biopsy for thin (< or =1.00-mm) cutaneous melanoma at a tertiary care cancer institute. Slides of tumor-positive SNs were reviewed by a melanoma pathologist to confirm nodal status and intranodal tumor burden, defined as isolated tumor cells, micrometastasis, or macrometastasis (< or =0.20, 0.21-2.00, or >2.00 mm, respectively). Nodal status was correlated with patient age and primary tumor depth (< or = 0.25, 0.26-0.50, 0.51-0.75, or 0.76-1.00 mm). Survival was determined by log-rank test.

MAIN OUTCOME MEASURES

Disease-free and melanoma-specific survival.

RESULTS

Of 1592 patients who underwent sentinel lymph node biopsy from 1991 to 2004, 631 (40%) had thin melanomas; 31 of the 631 patients (5%) had a tumor-positive SN. At a median follow-up of 57 months for the 631 patients, the mean (SD) 10-year rate of disease-free survival was 96% (1%) vs 54% (10%) for patients with tumor-negative vs tumor-positive SNs, respectively (P < .001); the mean (SD) 10-year rate of melanoma-specific survival was 98% (1%) vs 83% (8%), respectively (P < .001). Tumor-positive SNs were more common in patients aged 50 years and younger (P = .04). The SN status maintained importance on multivariate analysis for both disease-free survival (P < .001) and melanoma-specific survival (P < .001).

CONCLUSIONS

The status of the SN is significantly linked to survival in patients with thin melanoma. Therefore, sentinel lymph node biopsy should be considered to obtain complete prognostic information.

WNT5A expression increases during melanoma progression and correlates with outcome

PURPOSE

Wnt ligands play a major role in development and are important in cancer. Expression microarray analysis correlates one member of this family, WNT5A, to a subclass of melanomas with increased motility and invasion. There are no large studies of clinical samples primarily addressing the importance of WNT5A in melanoma progression or outcome. Therefore, this study aimed to assess the protein expression of WNT5A during melanoma progression and its effect on outcome.

EXPERIMENTAL DESIGN

Expression of WNT5A was determined in a series of 59 primary melanomas with matched metastases. To provide a benchmark of progression against which to assess WNT5A, expression of p16(ink4a) was analyzed, as this has been previously well documented in melanoma. The effect of WNT5A protein expression on outcome was assessed in 102 melanomas.

RESULTS

Cytoplasmic WNT5A showed a trend of increasing expression with melanoma progression (P = 0.013), whereas there was diminishing p16(ink4a) expression (P = 0.006). Nevi showed relatively strong WNT5A expression. Strong cytoplasmic WNT5A was an independent risk factor for reduced metastasis-free and overall survival in multivariate analysis (P = 0.001 and 0.003, respectively).

CONCLUSION

Cytoplasmic WNT5A increases with melanoma progression and strong expression is associated with poor outcome.

Lymphatic invasion revealed by multispectral imaging is common in primary melanomas and associates with prognosis

Lymphatic invasion by tumor cells has been noted infrequently in primary melanomas. Our primary hypotheses were that using immunohistochemical markers of lymphatic vessels and of tumor cells would improve detection of lymphatic invasion and that lymphatic invasion would correlate with regional nodal metastatic disease. This study included 106 patients who were diagnosed between 1972 and 1991 and who had 10 years or more of follow-up. We performed dual immunohistochemical stains for podoplanin (for lymphatic vessels) and S-100 (for melanoma cells). Lymphatic invasion was identified by light microscopy and confirmed by multispectral imaging analysis. Lymphatic invasion was detected by morphology alone in 5 cases (4.7%) in contrast to immunohistochemical staining augmented by multispectral imaging analysis where 35 cases (33%) were identified (P < .0001). Lymphatic invasion was significantly associated with time to regional nodal metastatic disease, as well as first metastasis and melanoma-specific death. "Local metastasis," defined by immunohistochemistry-detected lymphatic invasion, satellites, or neural invasion, identified 64% of those who had regional nodal metastatic disease within 5 years of diagnosis. Lymphatic invasion is an underobserved phenomenon in primary melanomas that can be better detected by immunohistochemical staining. The presence of lymphatic invasion may be a clinically useful predictor of regionally metastatic disease.

Sentinel lymph node biopsy in patients with thin melanomas

The aim of the present study is to report our experience with lymphatic mapping (LM) and sentinel lymph node biopsy (SLNB) in a selected group of patients with thin primary cutaneous melanomas. Fifty patients (22 females and 28 males; mean age, 57.8 years; range, 30-77 years) with a mean tumor thickness of 0.63 mm (range, 0.24-1.00 mm) underwent LM/SLNB. Twenty-eight (56%) of them had Clark level II, 20 (40%) had Clark level III, and two (4%) had Clark level IV. Tumor ulceration was present in two patients (4%) and histological regression in 35 patients (70%). Sentinel lymph node (SLN) metastases occurred in two of 50 patients (4%). The first case was a 0.88-mm thick, Clark level III, non-ulcerated superficial spreading melanoma of the trunk, without any regression. The second case was a 0.95-mm thick, Clark level IV, non-ulcerated superficial spreading melanoma of the neck, with regression. Both patients were disease-free 76 and 50 months after the SLNB procedure and followed complete lymph node dissection, respectively. The patients with negative SLN were disease-free after a median follow up of 44 months (mean, 43.2; range, 15-84 months). Published data and our experience suggest that LM/SLNB is not routinely indicated for melanomas less than 0.75 mm. Our results confirmed the accuracy of the new American Joint Committee on Cancer/International Union Against Cancer criteria, in which SLNB is required for thin melanomas less than 1.0 mm when they have ulceration or Clark level IV and V invasion.

An Integrated Tree-Based Classification Approach to Prognostic Grouping with Application to Localized Melanoma Patients

We propose an integrated tree-based approach for prognostic grouping of localized melanoma patients. This approach incorporates the survival tree model with the agglomerative hierarchical clustering to group terminal subgroups with similar prognoses together. The Brier score is used to evaluate the goodness of fit and the k-fold cross-validation test is used to evaluate the reproducibility of the scheme for prediction. The proposed approach is applied to an American Joint Committee on Cancer (AJCC) localized melanoma data set and compared with the current AJCC staging system. This approach performs more efficiently than the standard tree methods and has made improvement over the current AJCC melanoma staging system.

Avaliação de 496 laudos anatomopatológicos de melanoma diagnosticados no município de Florianópolis, Santa Catarina, Brasil

FUNDAMENTOS- O melanoma é a mais letal das neoplasias cutâneas, e sua incidência vem aumentando em todo o mundo. O conhecimento estatístico do comportamento biológico do melanoma cutâneo em Florianópolis é fundamental tanto para orientar o raciocínio clínico da prática ambulatorial diária como para auxiliar políticas de saúde pública. OBJETIVOS - Estabelecer dados epidemiológicos sobre melanoma em Florianópolis, Brasil. MÉTODOS - Foram analisados 496 laudos de 432 pacientes com diagnóstico histopatológico de melanoma, de dois centros de serviços de anatomia patológica entre primeiro de janeiro de 1999 e 31 de dezembro de 2004 em Florianópolis. O protocolo, baseado no questionário do Grupo Brasileiro de Melanoma, incluiu sexo, tipo histológico, presença de nevo no tumor, índice de Breslow, ulceração, mitose, presença de infiltrado inflamatório, margens e presença de metástase. RESULTADOS - Observaram-se 186 melanomas in situ, 210 invasivos, e 100 metastáticos. O tipo histológico mais comum foi o melanoma extensivo superficial (60%). A média de Breslow dos melanomas lentigo maligno e extensivo superficial foi 1,829mm e dos melanomas nodular e acral de 5,035mm (p< 0,0001). Os principais locais de metástases foram a pele e o subcutâneo, linfonodos e o cérebro. CONCLUSÕES - O perfil histopatológico do melanoma cutâneo observado neste estudo foi de melanoma tipo extensivo superficial, invasivo, com Breslow de 1,25mm, com infiltrado inflamatório e margens livres.

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.

Malignant melanoma in the 21st century, part 2: staging, prognosis, and treatment

Critical to the clinical management of a patient with malignant melanoma is an understanding of its natural history. As with most malignant disorders, prognosis is highly dependent on the clinical stage (extent of tumor burden) at the time of diagnosis. The patient's clinical stage at diagnosis dictates selection of therapy. We review the state of the art in melanoma staging, prognosis, and therapy. Substantial progress has been made in this regard during the past 2 decades. This progress is primarily reflected in the development of sentinel lymph node biopsies as a means of reducing the morbidity associated with regional lymph node dissection, increased understanding of the role of neoangiogenesis in the natural history of melanoma and its potential as a treatment target, and emergence of innovative multimodal therapeutic strategies, resulting in significant objective response rates in a disease commonly believed to be drug resistant. Although much work remains to be done to improve the survival of patients with melanoma, clinically meaningful results seem within reach.

Regional Nodal Metastatic Disease Is the Strongest Predictor of Survival in Patients with Thin Vertical Growth Phase Melanomas: A Case for SLN Staging Biopsy in These Patients

BACKGROUND

The benefit of sentinel lymph node (SLN) biopsy for patients with thin (< or =1.0 mm) melanomas, even for prognostic value, is controversial. This may partly result from the relatively small number and short follow-up of SLN-positive patients in this group. Previously, we have shown that clinical regional nodal metastatic disease (RNMD) serves as a good surrogate for SLN positivity. Here, we use RNMD as a validated surrogate for SLN positivity and examine its prognostic value in a large pre-SLN group of patients with thin vertical growth phase (VGP) lesions who would today commonly be offered SLN biopsy in our practice.

METHODS

Between 1972 and 1991, 472 patients with thin VGP melanomas with at least 10 years' follow-up were eligible for the study. Kaplan-Meier survival curves were computed for patients with and without RNMD. A multivariate Cox model and classification tree analysis were used to evaluate clinical and histopathologic predictors of survival.

RESULTS

Sixty-seven patients (14.2%) developed recurrence, 53.7% of whom developed RNMD. Forty-five patients (9.5%) experienced melanoma-related deaths (MRD). The most statistically significant predictor of MRD was RNMD (hazard ratio [HR] 13.5, P < .0001). Thickness (HR 10.5, P = .004), axial location (HR 4.6, P = .001), and age >60 years (HR 2.7, P = .005) additionally were independently associated with an increased risk of MRD. RNMD patients demonstrated a 44.4% 10-year disease-specific mortality.

CONCLUSIONS

RNMD was the most statistically significant factor associated with MRD in patients with thin VGP lesions. This supports the prognostic use of SLN biopsy in this group, recognizing that additional factors, including thickness, axial location, and older age were independently associated with a worse survival outcome.

Significance of cell kinetic parameters in the prognosis of malignant melanoma: a review

Malignant melanoma has been extensively studied concerning methods of predicting progression and clinical outcome. The maximum tumor thickness as measured by Breslow's method is the cornerstone prognostic criterion, but despite this, evolution of the disease in some patients remains unpredictable, confirming that new reliable prognostic factors are awaited. Cell kinetic evaluation has been shown to be a useful tool for assessing the prognosis of breast and gastrointestinal cancer patients. Indeed, in these fields, the mitotic index and MIB-1 expression index, which are indirect estimates of the growth fraction of tumor cell population, are commonly shown to correlate with tumor grade and patient survival and presented as prognostic factors. In melanoma, results of cell kinetic investigations are conflicting: some studies have established a link between high proliferative activity and a bad prognosis, whereas other reports suggest the opposite. The aim of this review is to discuss these findings.

Predicting sentinel node status in AJCC stage I/II primary cutaneous melanoma

BACKGROUND

Sentinel lymph node (SLN) status is an important prognostic factor for survival for patients with primary cutaneous melanoma. To address the issue of selecting patients at high and low risk for a positive SLN, prognostic factors were sought that predict SLN involvement by examining characteristics of both the primary tumor and the patient within the context of a biological model of melanoma progression.

METHODS

The study included 682 patients with primary vertical growth phase (VGP) melanoma and no clinical evidence of metastatic disease who underwent SLN biopsy (1995-2003). Logistic regression and classification tree analyses were used to investigate the association between SLN positivity and Breslow thickness, Clark level, tumor infiltrating lymphocytes (TIL), ulceration, mitotic rate (MR), lesion site, gender, and age. RESULTS.: In all, 88 of the 682 patients had > or =1 positive SLN (12.9%). In the multivariate analysis, MR, TIL, and thickness were found to be independent prognostic factors for SLN positivity. In the classification tree, four different risk groups were defined, ranging from minimal risk (2.1%) to high risk (40.4%). In lesions < r =2.0 mm, MR was important in risk-stratifying patients, and in lesions >2.0 mm TIL was important.

CONCLUSIONS

By incorporating biologically based variables such as VGP, TIL, and MR along with thickness into a prognostic model, both patients at high risk and minimal risk for SLN positivity can be identified. If validated, this model can be used in patient management and trial design to select patients to undergo or be spared SLN biopsy.

Molecular mechanisms of metastasis

A major topic covered at the First International Symposium on Cancer Metastasis and the Lymphovascular System was the molecular mechanisms of metastasis. This has become of major interest in recent years as we have discovered new metastasis-related genes and gained understanding of the molecular events of lymphatic metastasis. The symposium covered new aspects and important questions related to the events of metastasis in both humans and animals. The basic and clinical related research covered in this topic represented many disciplines. The presentations showed novel findings and at the same time, raised many new unanswered questions, indicating the limited knowledge we still have regarding the molecular events of metastasis. The hope is that further unraveling of the direct and indirect molecular events of lymphatic metastasis will lead to new approaches in developing effective therapeutics.

Early-Stage Melanoma: Staging Criteria and Prognostic Modeling

Accurate risk assessment is central to the process of making rational surgical and systemic treatment recommendations for melanoma patients and in establishing appropriate clinical trial stratification criteria. The current American Joint Commission on Cancer melanoma staging system incorporated relevant prognostic variables to provide a framework for the estimation of risk for recurrence; however, significant prognostic heterogeneity exists within the stage groupings. In the stage I/II group, survival rates range from 40% to 95% as defined by the combination of tumor thickness and ulceration. The use of novel prognostic factors, such as mitotic rate, sentinel node biopsy, and prognostic modeling using a variety of factors, can minimize this prognostic heterogeneity and provide a more accurate and individualized prognostic profile. Recent modifications in the stage III criteria include the number of positive nodes, whether the nodal disease is microscopic or clinically apparent, and the presence of an ulcerated primary. Through these factors, survival estimates can be provided, but like the stage I/II group, wide ranges in prognosis exist. The complexion of the stage III population is in evolution as a result of increasing numbers of patients being diagnosed as having microscopic sentinel node disease. Contemporary efforts are focused on defining the prognosis and natural history of this group. Through prognostic modeling using the number of nodes involved, ulceration status, and a measure of disease burden--disease in the sentinel node--relatively homogeneous subgroups can be identified. Long-term follow-up of patients staged with PCR molecular techniques on sentinel nodes shows conflicting value in assessing prognosis and therefore cannot be routinely used outside a clinical trial. The combination of genomic profiling using microarray analyses and the development of targeted therapy holds the future promise of individualizing prognosis and therapy.

Pathology of Melanoma: Fig. 1

The purposes of pathologic examination of a lesion suspected of being a malignant melanoma are to provide an accurate diagnosis of melanoma (or not), and to provide prognostic information useful in the clinical management of the patient. In the near future, pathologic attributes will also likely be used to predict responses to therapy, as a guide to the selection of specific therapeutic agents such as "small molecule" inhibitors of signaling pathways.

New American Joint Commission on Cancer Staging System for Melanoma: Prognostic Impact and Future Directions

Accurate melanoma staging is critical in establishing management strategies and estimating disease relapse. Combined with assessment of comorbidities and understanding treatment toxicities, risk assessment is central to offering appropriate surgical or systemic therapies. The American Joint Commission on Cancer (AJCC) melanoma staging system provides survival estimates within anatomically defined disease categories. Newer prognostic factors and methods of prognostic analyses can augment predictions for the presence of micro-metastatic disease and further define the risk for relapse. This article highlights relevant changes, evidence supporting future incorporation of more recently defined prognostic variables, novel approaches used as adjuncts to the current staging system, and future directions of the AJCC staging committee.

Estimates of stage-specific survival are altered by changes in the 2002 American Joint Committee on Cancer staging system for melanoma

BACKGROUND

The objectives of the current study were to examine how the estimated stage-specific survival is altered in the 2002 American Joint Committee on Cancer (AJCC) melanoma staging system compared with the 1997 AJCC staging system and to contrast the predictive accuracy of the 2 staging systems.

METHODS

There were 5847 consecutive melanoma patients who presented to Memorial Sloan-Kettering Cancer Center from 1996 to 2004 and who were entered prospectively into a data base. These patients were staged according to both the 1997 and 2002 AJCC staging criteria. Overall survival estimates were determined using the Kaplan-Meier method. The overall predictive accuracy of the two staging systems was compared using concordance estimation.

RESULTS

In total, 1035 patients were shifted to a lower stage in the 2002 staging system, whereas only 15 patients were upstaged. The number of patients with Stage I melanoma increased by 697 under the 2002 system (n = 2166 patients) compared with the 1997 system (n = 1463 patients). Because of the changes in 2002, the estimated 5-year overall survival for patients with Stage II melanoma decreased considerably, from 79% (1997) to 64% (2002). With the initiation of subgroups in 2002, it became apparent that patients with Stage III melanoma were very heterogeneous in terms of their survival probabilities (5-yr overall survival ranged from 70% in patients with Stage IIIA disease to 24% in patients with Stage IIIC disease). Furthermore, in the 2002 system, there was substantial prognostic overlap between Stage II and Stage III. Despite the increased complexity of the 2002 system, the 2 staging systems had similar concordance estimates: 58% for the 1997 staging system compared with 58% (ignoring the subgroups) and 59% (with subgroups) for the 2002 system.

CONCLUSIONS

Estimates of stage-specific survival were altered substantially by the changes made in the 2002 AJCC staging system for melanoma, particularly for Stage II. Stage subgroups that were added in the 2002 system resulted in a large diversity of risk within Stage III. This must be taken into account to stratify patients properly for clinical trials. The increased complexity of the 2002 system did not improve its predictive ability over the simpler 1997 system, highlighting the importance of developing individualized risk-prediction models.

Predictors of regional nodal disease in patients with thin melanomas

BACKGROUND

Most melanoma patients present with thin (<or=1.0 mm) lesions. Indications for sentinel lymph node (SLN) biopsy are not well defined for this group. Previously, we reported an association between mitotic rate (MR) and SLN positivity in these patients. The study was limited by a relatively small sample size and low statistical power. In this study, we evaluated a large population of patients with thin melanoma from the pre-SLN era to identify predictors of regional nodal disease (RND) that may serve as a surrogate for SLN positivity.

METHODS

Eight hundred eighty-two patients evaluated between 1972 and 1991 were included in the study. Univariate and multivariate regression analyses were performed by using clinical and histological data to identify factors associated with RND. A multivariate logistic regression model was developed and applied to the previously reported group of patients with thin melanomas who underwent SLN biopsy between 1996 and 2004 for validation.

RESULTS

Thirty-eight patients (4.3%) had evidence of RND. In the multivariate analysis, a MR>0, vertical growth phase (VGP), male sex, and ulceration were statistically significant predictors of RND. Patients at the highest risk according to a classification tree analysis (VGP and MR>0) had an RND rate of 11.9%. The regression model developed predicted well the SLN status in the validation sample.

CONCLUSIONS

Investigation of a large pre-SLN population identified MR>0, ulceration, VGP, and male sex as independently predictive of RND in patients with thin melanomas. These factors may help to identify subgroups of these patients that have clinically significant risks of SLN positivity.

Should all melanoma patients undergo sentinel lymph node biopsy?

PURPOSE OF REVIEW

It is now well established that sentinel lymph node biopsy is a powerful test to predict prognosis for melanoma patients. Controversy exists, however, regarding the appropriate selection of patients for sentinel lymph node biopsy, especially among patients with thin melanomas (< 1 mm Breslow thickness), thick melanomas (> 4 mm Breslow thickness), or locally recurrent melanoma.

RECENT FINDINGS

The majority of the studies in the past 2 years regarding sentinel lymph node biopsy have been concerned with identifying factors that can better predict regional nodal metastasis and survival. Other studies have proposed a better risk stratification model, which includes these factors, to best select those patients at increased risk of nodal positivity.

SUMMARY

Although much research has been done to select appropriate patients for sentinel lymph node biopsy based on multiple prognostic factors, further studies are necessary to completely define the indications for this procedure in patients with thin, thick and locally recurrent melanomas.

American Joint Committee on Cancer Clinical Stage as a Selection Criterion for Sentinel Lymph Node Biopsy in Thin Melanoma

BACKGROUND

A significant proportion of newly diagnosed melanomas are thin lesions (< or = 1.00 mm). Because tumor thickness correlates with the risk for nodal metastases, sentinel lymph node (SLN) biopsy in this subset is controversial. Incorporating other prognostic factors (Clark level and ulceration), we evaluated the 6th edition American Joint Committee on Cancer (AJCC) clinical stage as a simple and widely applicable guideline for offering SLN biopsy for thin melanoma.

METHODS

This study was a review of a prospective melanoma SLN database from 1993 to 2003 with emphasis on SLN positivity rates based on the 6th edition AJCC primary tumor thickness intervals and clinical stage.

RESULTS

Three hundred five patients underwent SLN biopsy, with an overall positivity rate of 17.7%. By the 6th edition AJCC, lesions < or = 1.00 mm had an SLN positivity rate of 6.6%. By 6th edition clinical stage, SLN positivity rates were 4.9% for stage IA and 10.4% for stage IB. By using stage IA as the criterion for not offering SLN biopsy, this procedure would have been avoided in 46% (39 of 85) of < or = 1.00-mm melanoma patients with a negative SLN.

CONCLUSIONS

Sixth edition AJCC clinical stage IB as a selection criterion for performing SLN biopsy in thin melanoma identifies most patients with a positive SLN while also avoiding a negative SLN biopsy in many patients. Until additional widely accepted and validated selection criteria are available, SLN biopsy for clinical stage IB, but not stage IA, thin melanomas is a reasonable approach.

Sentinel lymph node biopsy in thin melanoma patients

BACKGROUND

We sought to determine the incidence of positive sentinel lymph nodes in thin melanoma (<or=1.0 mm) patients and if subgroups could be identified with a higher risk of occult nodal disease.

METHODS

Patients with <or=1.0 mm lesions treated between 1997 and 2003 were reviewed. Sentinel nodes underwent microscopic analysis including step sectioning and immunohistochemical examination. Some nodes underwent reverse transcriptase-polymerase chain reaction (RT-PCR) evaluation for melanoma markers.

RESULTS

Sixty-four of 107 thin melanoma patients underwent sentinel node biopsy (SNB). Mapped patients were more likely to have Clark >or= III and thicker lesions (mean 0.77 mm vs. 0.47 mm), but were not different in regards to age, sex, or lesion location. Eight percent and 58% of sentinel nodes were positive by routine histology and RT-PCR, respectively. Among mapped patients, younger age was the only significant prognostic factor for node positivity. With a median follow-up of 18 months among all patients, one regional recurrence (at 2 years) has been identified.

CONCLUSIONS

Given the low morbidity of sentinel lymph node biopsy, this procedure should be discussed with selected thin melanoma patients to detect microscopic disease, however PCR positivity by our methods is too commonly seen to be clinically significant in thin melanoma patients and requires additional study.

Cutaneous melanoma: prognostic factors

BACKGROUND

Recent data have changed our views of prognostic factors in cutaneous melanoma. While some newer methods have yielded better prognostic information, some insights have evolved as a result of large-scale population-based analyses.

METHODS

We review current data on several different prognostic factors and divide these factors according to their application in localized primary melanoma or metastatic melanoma. For each prognostic factor, the level of evidence supporting its use and its applicability to clinical practice are considered.

RESULTS

For localized primary melanoma, the dominant predictors of survival include lesion thickness, ulceration, and lymph node involvement. Factors such as age, sex, anatomic location, and satellite/in-transit lesions are important in localized melanoma. Factors currently being investigated are tumor vascularity, vascular invasion, mitotic rate, tumor regression, and tumor-infiltrating lymphocytes. For metastatic melanoma, the most important prognostic factors are site of metastases and the presence of elevated serum lactic dehydrogenase. The value of these prognostic factors to clinicians caring for melanoma patients is discussed.

CONCLUSIONS

A better understanding of prognostic factors in cutaneous melanoma has evolved over the last decade, allowing oncologists to provide appropriate treatment for their patients. Many of the prognostic factors are interrelated. In the near future, it is expected that several molecular genetic factors will provide more insight into the prognosis of patients with melanoma.

Cutaneous melanoma: estimating survival and recurrence risk based on histopathologic features

The prognosis of melanoma is best understood in terms of a model of tumor progression, in which most melanomas may evolve through two major phases of progression: from a lesion that is nontumorigenic and has little or no capacity for metastasis; to a more advanced lesion that is tumorigenic and may have capacity for metastasis. The likelihood of metastasis varies with a number of attributes of the primary melanoma, including the phase of progression, the Breslow tumor thickness, mitotic rate, and host response to the tumorigenic compartment of the lesion, Clark's level of invasion, and other factors. When distant metastasis has occurred, the prognosis for the patient is very poor. In this monograph, the focus will be the discussion of factors related to the prognosis of melanomas that at diagnosis are clinically localized to the primary site.

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.

Sentinel node metastasectomy in thin ≤1-mm melanoma

BACKGROUND AND AIMS

Sentinel lymph node biopsy (SLNB) has been widely accepted as a precise tool to stage melanoma. In thin T1 melanomas (<or=1 mm), the indication of SLNB is controversial since the risk of nodal metastasis is low. The aim of this study was to assess if SLNB detects occult nodal metastases among patients with thin melanomas.

PATIENTS AND METHODS

SLNB was performed prospectively in 135 patients with invasive melanoma in any depth category, including 56 T1 melanomas.

RESULTS

Nodal metastases were detected in 18% by SLNB, and there were three sentinel-positive thin melanomas, constituting 5% of the T1 cases. Histopathologically, there were no factors of the primary tumors that would have predicted these metastases.

CONCLUSION

SLNB is a precise method to detect clinically silent nodal metastases in thin invasive melanoma. Certain histopathologic features of a thin primary lesion may correlate with the predictive probability of the sentinel node status. We were unable to identify these predictors, but the conclusions from this study are limited by the small sample size. Advanced melanoma is a lethal disease, and accurate staging is essential also in the T1 group. For stage III patients with occult nodal metastases, metastasectomy is a better option for cure than observation.

Mitotic rate as a predictor of sentinel lymph node positivity in patients with thin melanomas

BACKGROUND

Lymphatic mapping and sentinel lymphadenectomy (LM/SL) provide important prognostic information for patients with early-stage melanoma. Although the use of this technique in patients with thin melanomas (< or =1.00 mm) is not routine, risk factors that may predict sentinel lymph node (SLN) positivity in this patient population are under investigation. We sought to determine whether mitotic rate (MR) is associated with SLN positivity in thin-melanoma patients and, therefore, whether it may be used to risk-stratify and select patients for LM/SL.

METHODS

Clinical and histopathologic variables were reviewed for 181 patients with thin melanomas who underwent LM/SL from January 1996 through January 2004. Univariate and multivariate logistic regression analyses were performed to identify factors associated with SLN positivity. Risk groups were defined on the basis of the development of a classification tree.

RESULTS

The overall SLN positivity rate was 5%. All patients with positive SLNs had an MR of >0. By univariate analysis, MR and thickness were significant predictors of SLN positivity. The association between MR and SLN positivity remained significant controlling for each of the other variables evaluated. On the basis of a classification tree, patients with an MR >0 and tumor thickness > or =.76 mm were identified as a higher-risk group, with an SLN positivity rate of 12.3%.

CONCLUSIONS

In patients with thin melanomas, MR >0 seems to be a significant predictor of SLN positivity that may be used to risk-stratify and select patients for LM/SL. To confirm these results, the predictive value of MR for SLN positivity needs to be validated in other populations of thin-melanoma patients.