Do micromorphometric features of metastatic deposits within sentinel nodes predict nonsentinel lymph node involvement in melanoma?

Sentinel lymph node assessment in melanoma: current state and future directions

Assessment of sentinel lymph node status is an important step in the evaluation of patients with melanoma for both prognosis and therapeutic management. Pathologists have an important role in this evaluation. The methodologies have varied over time, from the evaluation of dimensions of metastatic burden to determination of the location of the tumour deposits within the lymph node to precise cell counting. However, no single method of sentinel lymph node tumour burden measurement can currently be used as a sole independent predictor of prognosis. The management approach to sentinel lymph node-positive patients has also evolved over time, with a more conservative approach recently recognised for selected cases. This review gives an overview of past and current status in the field with a glimpse into future directions based on prior experiences and clinical trials.

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.

Nodal Recurrence is a Primary Driver of Early Relapse for Patients with Sentinel Lymph Node-Positive Melanoma in the Modern Therapeutic Era

BACKGROUND

Management of patients with sentinel lymph node (SLN)-positive melanoma has changed dramatically over the last few years such that completion lymph node dissection (CLND) has become uncommon, and many patients receive adjuvant immunotherapy or targeted therapy. This study seeks to characterize patterns and predictors of early recurrence in this setting.

PATIENTS AND METHODS

All patients with primary cutaneous melanoma undergoing sentinel lymph node biopsy (SLNB) between 3/2016 and 12/2019 were identified. The subset with a positive SLN who did not undergo CLND were examined for further analysis of outcomes and predictors of recurrence.

RESULTS

Overall, 215 patients with SLN-positive melanoma who did not have CLND were identified. Adjuvant systemic therapy was administered to 102 (47%), with 93% of this subset receiving immunotherapy (n = 95). Median follow-up from SLNB was 20 months (IQR 12-28.5 months), and 57 patients (27%) recurred during this time. The SLN basin was the most common site of recurrence (n = 38, 67% of recurrence), with isolated nodal recurrence being the most common first site of recurrent disease (n = 22, 39% of recurrence). On multivariable analysis, lymphovascular invasion (LVI) of the primary tumor, two or more involved nodes, and > 1 mm nodal deposit were independently associated with higher rates of nodal relapse.

CONCLUSIONS

Nodal recurrence is a primary driver of early disease relapse for patients with SLN-positive melanoma who do not undergo CLND in the era of effective adjuvant systemic therapy. LVI, ≥ 2 nodes, or > 1 mm nodal disease identifies patients at particularly high risk of nodal relapse.

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.

Pathology of Melanoma

Melanoma is an aggressive malignancy arising from melanocytes in the skin and rarely in extracutaneous sites. The understanding of pathology of melanoma has evolved over the years, with the initial classifications based on the clinical and microscopic features to the current use of immunohistochemistry and genetic sequencing. The depth of invasion and lymph node metastasis are still the most important prognostic features of melanoma. Other important prognostic features include ulceration, lymphovascular invasion, mitosis, and tumor-infiltrating lymphocytes. This article reviews the pathology of melanoma and its precursor lesions, along with the recent advances in pathologic diagnosis of melanoma.

Histological immune response patterns in sentinel lymph nodes involved by metastatic melanoma and prognostic significance

BACKGROUND

To further characterize the micromorphometric immunological pattern to metastatic melanoma in sentinel lymph node (SLN) biopsies and completion lymph node (CLN) dissections and their relation to 5-year overall survival (OS).

METHODS

Retrospective cohort of 49 patients from 1996 to 2005 with a positive SLN who underwent CLN dissection (CLD) was studied. Micromorphometric characteristics included follicular center count (FCC)/profile, sinus histiocytosis, metastatic size, tumor infiltrating lymphocytes (intranodal), paracortical dendritic cells, germinal center reaction and morphology. Comparison of Kaplan-Meier survival curves used the exact log-rank statistic.

RESULTS

In the high-FCC (n = 5-51) vs the low-FCC (n < 5) lymph nodes, a delayed separation occurred at 3 years, with 5-year OS rates being 73% vs 54% in the high- and low-FCC groups, respectively. Improved survival up to 3 years was also noted in CLDs that showed a higher FCC when compared to the prior SLN. Patients with metastatic deposits >2 mm had significantly lower 5-year survival (both <.001).

CONCLUSIONS

Nodal micromorphometric features (ie, FCC) are probably related to host immune response to metastasis. Quantitative evaluation of lymphoid follicular centers could provide valuable prognostic information to help to stratify 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.

SLN melanoma micrometastasis predictivity of nodal status: a long term retrospective study

Background

Completion lymph node dissection (CLND) is the gold standard treatment for patients with a positive sentinel lymph node (SLN) biopsy. Considering the morbidity associated with CLND it is important to identify histological features of the primary tumor and/or of SLN metastasis that could help to spare from CLND a subset of patients who have a very low risk of non-SLN metastasis. The objective of this study is to identify patients with a very low risk to develop non-SLNs recurrences and to limit unnecessary CLND.

Methods

A retrospective long-term study of 80 melanoma patients with positive SLN, undergone CLND, was assessed to define the risk of additional metastasis in the regional nodal basin, on the basis of intranodal distribution of metastatic cells, using the micro-morphometric analysis (Starz classification).

Results

This study demonstrates that among the demographic and pathologic features of primary melanoma and of SLN only the Starz classification shows prognostic significance for non-SLN status (p<0.0001). This parameter was also significantly associated with disease-free survival rate (p<0.0013).

Conclusion

The Starz classification can help to identify, among SLN positive patients, those who can have a real benefit from CLND. From the clinical point of view this easy and reliable method could lead to a significant reduction of unnecessary CLND in association with a substantial decrease in morbidity. The study results indicate that most of S1 subgroup patients might be safely spared from completion lymphatic node dissection. Furthermore, our experience demonstrated that Starz classification of SLN is a safe predictive index for patient stratification and treatment planning.

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.

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.

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.

Lymphovascular Invasion as a Prognostic Factor in Melanoma

The prognostic significance of lymphovascular invasion (LVI) in melanoma remains controversial. Clinicopathologic data from a prospective trial of patients with melanoma were analyzed with respect to LVI. Disease-free survival and overall survival (OS) were evaluated by Kaplan-Meier (KM) analysis. Univariate and multivariate analyses were performed to evaluate factors predictive of tumor-positive sentinel nodes (SLN) and survival. A total of 2183 patients were included in this analysis; 171 (7.8%) had LVI. Median follow-up was 68 months. Factors associated with LVI included tumor thickness, ulceration, and histologic subtype ( P < 0.05). LVI was associated with a greater risk of SLN metastasis ( P < 0.05). By KM analysis, LVI was associated with worse OS ( P = 0.0009). On multivariate analysis, age, gender, thickness, ulceration, anatomic location, and SLN status were predictors of OS; however, LVI was not an independent predictor of OS. Among patients with regression, the 5-year OS rate was 49.4 per cent for patients with LVI versus 81.1 per cent for those with no LVI ( P < 0.0001). LVI is associated with a greater risk of SLN metastasis. Although LVI is not an independent predictor of OS in general, it is a powerful predictor of worse OS among patients who have evidence of regression of the primary tumor.

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.

Sentinel lymph nodes in cutaneous melanoma: handling, examination, and clinical repercussion

CONTEXT

Within the last 15 years, evaluation of sentinel lymph nodes (SLNs) has become the most popular method of early staging of several malignancies, including melanoma. Sentinel lymph nodes are usually examined on formalin-fixed, paraffin-embedded sections and by routine histology/immunohistochemistry (research protocols have used other techniques such as polymerase chain reaction). Approximately 20% of patients with cutaneous melanoma have metastasis in the SLN. In most studies, detection of positive SLN conveys a poorer prognosis for patients with cutaneous melanoma.

OBJECTIVE

To review the morphologic patterns of melanoma metastasis in the SLN, the differential diagnosis, and the quantification of tumor burden as a prognostic factor.

DATA SOURCES

Personal observations and review of the pertinent literature.

CONCLUSIONS

Evaluation of sentinel lymph nodes is certainly becoming a widespread technique and most authors agree on its prognostic power for staging patients with cutaneous melanoma. Current studies are evaluating the possible therapeutic value of removal of positive SLNs.

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.

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.

Surgical management of primary disease

Despite advancements in the treatment of melanoma, surgical management remains the cornerstone for treatment and long-term survival. The authors present their surgical approach to the patient with melanoma including evaluation, treatment, and reconstruction. In addition, management of melanoma occurring in difficult anatomic areas and in special patient populations is reviewed.

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 Lymph Nodes in Cutaneous Melanoma

Examination of sentinel lymph nodes (SLN) has probably become the most popular method of early staging of patients who have cutaneous melanoma because SLN are considered to be the lymph nodes most likely to contain metastatic deposits; they can be examined in a more intense manner than in standard lymphadenectomy. There are several protocols to examine SLN but most of them use formalin-fixed, paraffin-embedded sections stained with hematoxylin and eosin with the addition of immunohistochemistry. By using these protocols, approximately 20% of patients who have cutaneous melanoma have melanoma cells in the SLN. Current studies are evaluating the possible therapeutic value of removal of positive SLN, but it is accepted by most authors that detection of positive SLN conveys an impaired prognosis for patients who have cutaneous melanoma.

Prognostic significance of a positive nonsentinel lymph node in cutaneous melanoma

PURPOSE

Sentinel lymph node (SLN) biopsy provides important prognostic information for patients with cutaneous melanoma. There may be additional prognostic significance to melanoma spreading from the SLN to nonsentinel lymph nodes (NSLN). We examined the implications of a positive NSLN for overall and distant disease-free survival.

METHODS

Using a prospectively maintained, Institutional Review Board-approved melanoma database we studied patients who had a cutaneous melanoma, a positive SLN, and a completion lymph node dissection (CLND). Survival was determined using a combination of hospital records and the Social Security Death Index (SSDI). Univariate and multivariate Cox regression analysis was performed to further characterize predictors of overall and distant disease-free survival. Kaplan-Meier analysis was used to generate survival curves.

RESULTS

A total of 429 patients with positive SLN biopsies were identified, with at least one positive NSLN identified in 71 (17%). Median follow-up time was 36.8 months. Presence of a positive NSLN was significantly associated with poor outcome, although long-term survival was possible. Presence of ulceration, high mitotic rate, angiolymphatic invasion, total number of positive nodes, and volume of disease>1% in the SLN were significant predictors of survival on univariate analysis, but lost significance on multivariate. Multivariate Cox analysis revealed several predictors of overall survival: increasing age [hazard ratio (HR) 1.04, P<0.01], Breslow depth (HR 1.76, P<0.01), presence of extracapsular extension in the SLN (HR 2.39, P<0.01), and positive NSLN (HR 1.92, P<0.01).

CONCLUSION

Among node-positive melanoma patients, presence of a positive NSLN is a highly significant poor prognostic sign, even after considering the total number of positive nodes and volume of disease in the SLN. CLND after a positive SLN provides this important prognostic information.

Is completion lymph node dissection needed in case of minimal melanoma metastasis in the sentinel node?

OBJECTIVE

The purpose of this study was to evaluate the micromorphometric Starz-classification in melanoma patients.

SUMMARY BACKGROUND DATA

The micromorphometric Starz-classification suggests that melanoma patients with a sentinel node metastasis invading no more than 0.3 mm (S-I) or 0.31 to 1.0 mm (S-II) below the capsular level can be spared further surgery, while invasion of the metastasis of more than 1.0 mm (S-III) implies a need for completion dissection.

METHODS

Seventy patients with sentinel node metastases were studied. Twenty patients with an S-I or S-II classification were spared further surgery and 50 S-III patients underwent completion dissection. The median follow-up time was 33 months.

RESULTS

No lymph node recurrences were detected in the 20 S-I, II patients. Six of the 50 S-III patients (12%) had additional involved nodes in the dissection specimen. In these patients no recurrences developed in the cleared regional basins. Overall 3-year survival was 100% in the S-I, II patients and 80% in the S-III patients (P = 0.04). Three-year disease-free survival rates were 83% and 60%, respectively (P = 0.40).

CONCLUSIONS

: This study suggests that further surgery is unnecessary in S-I and S-II patients, while it does seem prudent to carry out completion dissection in S-III patients. The distinct survival difference between the 2 groups of patients suggests that the S-classification also has prognostic implications.