Patterns of recurrence following a negative sentinel lymph node biopsy in 243 patients with stage I or II melanoma

Reducing workload in malignant melanoma sentinel node examination: a national study of pathology reports from 507 melanoma patients

AIMS

Even though extensive melanoma sentinel node (SN) pathology protocols increase metastasis detection, there is a need for balancing high detection rates with reasonable workload. A newly tested Danish protocol recommended examining nodes at six levels 150 µm apart (six-level model) and using SOX10 and Melan-A immunohistochemistry (IHC). We explored if a protocol examining 3 levels 300 µm apart (three-level model) combined with IHC would compromise metastasis detection. The study aim was to optimise the protocol to reduce workload without compromising detection rate.

METHODS

8 months after protocol implementation, we reviewed the pathology reports of SNs from 507 melanoma patients nationwide, including 117 SN-positive patients. Each report was reviewed to determine histopathological features, including detection of metastasis, exact levels with metastasis, exact levels with metastasis >1 mm in diameter and IHC results.

RESULTS

The six-level model detected metastases in 23% of patients, whereas the three-level model would have detected metastases in 22% of patients. The three-level model would have missed a few small metastases (n=4), measuring <0.1 mm, 0.1 mm, 0.4 mm and 0.1 mm, respectively. The six-level model detected metastases >1 mm in 7% of patients. One of these metastases (measuring 1.1 mm) would have been detected by the three-level model, but not as >1 mm. SOX10 and Melan-A had equal sensitivity.

CONCLUSIONS

Reducing the number of levels examined to three levels 300 µm apart combined with IHC does not have significant impact on metastasis detection rate, and we will therefore recommend that the future melanoma SN guideline takes this into consideration to reduce overall workload.

Intraoperative Immunohistochemistry During Mohs Micrographic Surgery and Staged Excision Decreases Local Recurrence Rates for Invasive Cutaneous Melanoma: A Systematic Review and Meta-Analysis

BACKGROUND

Mohs micrographic surgery (MMS) is increasingly used to treat cutaneous melanoma. However, it is unclear whether intraoperative immunohistochemistry (IHC) improves surgical outcomes.

OBJECTIVE

To determine whether intraoperative IHC during MMS and staged excision is associated with a decreased risk of poor surgical outcomes.

MATERIALS AND METHODS

Search of 6 databases identified comparative and noncomparative studies that reported local recurrence after MMS or staged excision with or without IHC for melanoma. Random-effects meta-analysis was used to estimate pooled local recurrence rates, nodal recurrence, distant recurrence, and disease-specific mortality.

RESULTS

Overall, 57 studies representing 12,043 patients with cutaneous melanoma and 12,590 tumors met inclusion criteria. Combined MMS and staged excision with IHC was associated with decreased local recurrence in patients with invasive melanoma (0.3%, 95% CI: 0-0.6) versus hematoxylin and eosin alone (1.8%, 95% CI: 0.8%-2.8%) [p < .001]. Secondary outcomes including nodal recurrence, distant recurrence, and disease-specific mortality were not significantly different between these 2 groups. Study heterogeneity was moderately-high.

CONCLUSION

Local recurrence of invasive melanoma is significantly lower after MMS and staged excision with IHC as opposed to without IHC. These findings suggest that the use of intraoperative IHC during MMS or staged excision should strongly be considered, particularly for invasive melanoma.Trial Registration PROSPERO Identifier: CRD42023435630.

The Evolution of the Sentinel Node Biopsy in Melanoma

The growing repertoire of approved immune-checkpoint inhibitors and targeted therapy has revolutionized the adjuvant treatment of melanoma. While the treatment of primary cutaneous melanoma remains wide local excision (WLE), the management of regional lymph nodes continues to evolve in light of practice-changing clinical trials and dramatically improved adjuvant therapy. With large multicenter studies reporting no benefit in overall survival for completion lymph node dissection (CLND) after a positive sentinel node biopsy (SLNB), controversy remains regarding patient selection and clinical decision-making. This review explores the evolution of the SLNB in cutaneous melanoma in the context of a rapidly changing adjuvant treatment landscape, summarizing the key clinical trials which shaped current practice guidelines.

Sentinel Lymph Node Biopsy for Extremity and Truncal Soft Tissue Sarcomas: A Systematic Review of the Literature

BACKGROUND

Regional lymph node metastasis (RLNM) occurs infrequently in patients with soft tissue sarcoma (STS), although certain STS subtypes have a higher propensity for RLNM. The identification of RLNM has significant implications for staging and prognosis; however, the precise impact of node-positive disease on patient survival remains a topic of controversy. Although the benefits of sentinel lymph node biopsy (SLNB) are well documented in patients with melanoma and breast cancer, whether this procedure offers a benefit in STS is controversial.

METHODS

A systematic literature search was performed and articles reviewed to determine if SLNB in patients with extremity/truncal STS impacts disease-free or overall survival.

RESULTS

Six studies were included. Rates of sentinel lymph node positivity were heterogeneous (range 4.3-50%). The impact of SLNB on patient outcomes remains unclear. The overall quality of available evidence was low, as assessed by the Grading of Recommendations, Assessment, Development, and Evaluation system.

CONCLUSIONS

The literature addressing the impact of nodal basin evaluation on the staging and management of patients with extremity/truncal STS is confounded by heterogeneous patient cohorts and clinical practices. Multicenter prospective studies are warranted to determine the true incidence of RLNM and whether SLNB could benefit patients with clinically occult RLNM at diagnosis.

A Proposed Method for Cervical Lymph Node Evaluation in Head and Neck Cancer Patients: A Radiological Study

Objectives

To present a new method to assess the cervical lymph nodes status in head and neck cancer patients.

Methods

Twenty-five oral and maxillofacial cancer patients underwent preoperative CT imaging. The cervical lymph node features on CT scan were examined. Each parameter was given a score, and the total scores in each case was calculated and referred to as metastatic score (MS). Then, patients underwent neck dissection, and all dissected lymph nodes were sent for histopathology.

Results

All cases with MS ≥ 6 were histopathologically positive, and all cases with MS ≤ 3 were histopathologically negative. All cases of nodal sizes > 3 cm were histopathologically positive, 82% of cases of nodal sizes between 2.1 and 3 cm were histopathologically positive, 40% of cases of nodal sizes between 1 and 2 cm were histopathologically positive, and all cases of lymph nodes sizes < 1 cm were histopathologically negative. Seventy-seven percent of cases which had a group of lymph nodes ≥ 3 nodes/region were histopathologically positive, while 79% of cases with rounded nodes were histopathologically positive, and all cases with necrotic lymph nodes were positive for malignancy.

Conclusion

The proposed formula is a good assessment tool for cervical lymph nodes evaluation using helical CT scan in head and neck cancer patients.

Detection of melanoma, breast cancer and head and neck squamous cell cancer sentinel lymph nodes by Tc-99m Tilmanocept (Lymphoseek®)

Technetium-99m-labeled Tilmanocept or Lymphoseek® (Cardinal Health, Dublin, Ohio) is a soluble, synthetic molecule with a small diameter (7 nm), which is comprised of technetium-99m chelated to a dextran backbone containing multiple units of mannose ligands with a high affinity for CD206, a receptor located on the surface of macrophages and dendritic cells that are found in high concentration in lymph nodes. It enables quick transit from the injection site and rapid lymph node accumulation. The binding of mannose ligand and CD206 results in the internalization of the ligand and receptor into the cell. Once the Technetium-99m-labeled Tilmanocept (Lymphoseek®) reaches the lymph node, it is readily internalized by the macrophages and dendritic cells within the draining lymph nodes. Technetium-99m-labeled Tilmanocept (Lymphoseek®) has been extensively studied as a radioisotope for detection of sentinel lymph nodes in melanoma, breast cancer and head and neck squamous cell carcinoma in clinical trials. Based on its safety and ability to detect sentinel lymph nodes satisfactorily, it has been approved by the FDA to use as a radioisotope for preoperative lymphoscintigraphy for identification of sentinel lymph nodes in these types of cancer. Further, the FDA has expanded approval of Technetium-99m-labeled for sentinel lymph node mapping of all solid tumors as well as in pediatric patients.

Risk factors and patterns of recurrence after sentinel lymph node biopsy for thin melanoma

While having a thin melanoma (defined as AJCC 8 T1 stage tumor ≤ 1.0 mm) with negative sentinel lymph node biopsy (SLNB) provides an excellent prognosis, some patients still develop recurrence and die. To determine risk factors for any recurrence (local/in-transit, nodal, distant) in thin melanoma patients with negative SLNB and assess survival outcomes. Retrospective review of thin melanomas with negative SLNB from 1999 to 2018 was performed. Two hundred and nine patients were identified. Clinicopathologic characteristics of the primary melanoma were collected. Patterns of recurrence for local/in-transit, nodal or distant recurrence and survival outcomes were analyzed. Eighteen patients (8.6%) developed recurrence: 3 (1.9%) local/in-transit, 4 (2.9%) regional/nodal, and 11 (5.3%) distant recurrence during a median follow-up time of 62 months. A multivariate Cox regression model showed that head and neck site (HR 3.52), ulceration (HR 10.8), and mitotic rate (HR 1.39) were significant risk factors for recurrence. Median time to first recurrence was 49 months. Patients with recurrence had a significantly worse 5 year overall survival than those without recurrence (82.2 vs 99.2%). A retrospective single center study and limited sample size. Did not factor in possible false negative SLNBs when calculating hazard ratios. For thin melanoma patients with negative SLNB, heightened surveillance is warranted for those with ulceration, primary tumor location on the head or neck, and elevated mitotic rate.

High discordance rate in assessing sentinel node positivity in cutaneous melanoma: Expert review may reduce unjustified adjuvant treatment

INTRODUCTION

Identification of sentinel node (SN) metastases can set the adjuvant systemic therapy indication for patients with stage III melanoma. Studies re-evaluating the diagnosis of initially positive SN biopsies are scarce.

MATERIALS AND METHODS

Dutch patients with melanoma who underwent SN biopsy between 2003 and 2014 were selected from PALGA, the Dutch Pathology Registry. Histopathological slides of SN-positive patients were retrieved for review. A random sample was reassessed by an expert melanoma pathologist. Recurrence-free survival (RFS) of patients who were misclassified (false-positive) was compared with those with a true positive SN status. For comparison, a group of SN-negative patients was included. Multivariable logistic analysis was performed to assess clinicopathological characteristics associated with misclassification of SN status.

RESULTS

Diagnosis was downgraded from melanoma metastasis to nodal nevus in 38 of the 322 reviewed patients (11.8%). Considering the inclusion criteria of phase III adjuvant trials, at least 4.3% of patients would have falsely qualified for adjuvant therapy. In multivariable analysis, patients with a low SN tumour burden and subcapsular SN tumour location had a significantly higher chance of being misclassified. The five-year RFS of the 38 downgraded patients was 86.7% (95% confidence interval [CI] = 72.6-96.6), similar to the 85.9% (95% CI = 84.9-86.8, p = 0.18) for 6413 SN-negative patients and better than the 53.2% (95% CI = 47.2-59.9, p = 0.009) of 284 patients who were truly SN positive upon review.

CONCLUSION

More than 10% of originally positive SN biopsies of patients with melanoma concern misclassified nodal nevi. We advocate that when adjuvant treatment is considered in patients with stage III melanoma, SN biopsies should be reassessed by an expert melanoma pathologist.

Re-evaluation of Sentinel Lymph Node Biopsy for Melanoma

OPINION STATEMENT

The vast majority of patients newly diagnosed with melanoma present with clinically localized disease, and sentinel lymph node biopsy (SLNB) is a standard of care in the management of these patients, particularly in intermediate thickness cases, in order to provide important prognostic data. However, SLNB also has an important role in the management of patients with other subtypes of melanoma such as thick melanomas, certain thin melanomas, and specific histologic variants of melanoma such as desmoplastic melanoma. Furthermore, there have been technical advances in the SLNB technique, such as the development of newer radiotracers and use of SPECT/CT, and there is some data to suggest performing a SLNB may be therapeutic. Finally, the management of patients with a positive sentinel lymph node (SLN) has undergone dramatic changes over the past several years based on the results of recent important clinical trials. Treatment options for patients with SLN metastases now include surveillance, completion lymph node dissection, and adjuvant therapy with checkpoint inhibitors and targeted therapy. SLNB continues to play a crucial role in the management of patients with melanoma, allowing for risk stratification, potential regional disease control, and further treatment options for patients with a positive SLN.

Sentinel lymph node biopsy in acral melanoma: A Korean single-center experience with 107 patients (2006-2018)

BACKGROUND

Sentinel lymph node biopsy (SLNB) of primary cutaneous melanoma as an important staging method has not been popularly undertaken in Korea and only a few studies with small patient numbers have been published.

AIM

We examined the clinical feasibility and overall outcomes of SLNB in acral melanoma (AM) of Korean in Kyungpook National University Hospital (KNUH) over the past 13 years.

METHODS

SLNB in AM patients during 2006-2018 were analyzed retrospectively for sentinel lymph node (SLN) harvesting rate, positivity rate, positivity-relevant overall survival (OS) and disease-free survival (DFS), and its side effects.

RESULTS

A total of 109 AM patients who underwent SLNB were enrolled. Harvested nodes were identified from 107 patients and SLN harvesting rate was 98.2%. The mean Breslow thickness (±standard deviation) was 3.38 ± 3.03 mm, and the proportion of ulcerated melanomas was 64%. Twenty-two (20.6%) had a tumor-positive SLN and, among them, 82% (18/22) underwent immediate complete lymph node dissection (CLND). The metastasis-positive nodal basin after CLND was detected in 16.7% of cases (3/18). Tumor-negative SLN cohorts showed significantly better OS and DFS than tumor-positive ones (P = 0.006 and P < 0.001 for each). Two side effects, one seroma and one lymphocele, were observed without major sequelae.

CONCLUSION

SLNB, crucial management of melanoma, proved its efficacy to predict patients' prognosis and could be performed successfully and safely in Korean AM patients by interdisciplinary cooperation between dermatology and other surgical departments. SLN(-) showed significantly better OS and DFS than SLN(+). Significant risk factors for DFS were Breslow thickness, the presence of ulceration and the presence of SLN metastasis. SLNB should be encouraged in order to stage melanoma accurately and direct the proper management in Korean AM.

Clinicopathological Features, Staging, and Current Approaches to Treatment in High-Risk Resectable Melanoma

The incidence of melanoma in the United States has been increasing over the past several decades. Prognosis largely depends on disease stage, with 5-year melanoma-specific survival ranging from as high as 99% in patients with stage I disease to less than 10% for some patients with stage IV (distant metastatic) disease. Fortunately, in the last 5-10 years, there have been remarkable treatment advances for patients with high-risk resectable melanoma, including approval of targeted and immune checkpoint blockade therapies. In addition, results of recent clinical trials have confirmed the importance of sentinel lymph node biopsy and continue to refine the approach to regional lymph node basin management. Lastly, the melanoma staging system was revised in the eighth edition AJCC Cancer Staging Manual, which was implemented on January 1, 2018. Here we discuss these changes and the clinicopathological features that confer high risk for locoregional and distant disease relapse and poor survival. Implications regarding the management of melanoma in the metastatic and adjuvant settings are discussed, as are future directions for neoadjuvant therapies.

Detection of Lymph Node Metastases by Ultra-pH-Sensitive Polymeric Nanoparticles

Lymph node (LN) dissection followed by histological analysis is the current standard for diagnosis of LN metastasis but the method suffers from patient morbidity and low sensitivity of detection. Ultra-pH sensitive (UPS) nanoparticles show remarkable accuracy in the delineation of primary tumor margins for precision cancer surgery. Herein we investigate the effectiveness of UPS nanoparticles to detect cancer-involved LNs. Methods: We synthesized a series of indocyanine green (ICG) conjugated UPS nanoparticles with distinct pK_a (UPS_5.3, UPS_6.1, and UPS_6.9). Systemically administered UPS-ICG nanoparticles in the 4T1.2-BALB/cj mouse model were imaged with real-time, near-infrared fluorescence (NIRF) to guide removal of LNs. Ex vivo imaging of gross tissue enabled quantification of fluorescence intensity. Histological analysis was used as the gold standard diagnostic test. Results: Macrophage uptake of UPS nanoparticles elevates the background signal in benign LNs. However, cancer foci within LNs show distinctive clustering of UPS-ICG fluorescence. UPS_5.3 achieves accurate detection of metastatic LNs as shown by a receiver operating characteristic (ROC) area under the curve (AUC) of 0.96 ± 0.03. UPS_6.1 and UPS_6.9 offer decreased discriminatory power at ROC AUC of 0.73 ± 0.1 and 0.88 ± 0.07, respectively. Conclusions: All UPS compositions show cancer-specific discrimination of metastatic LNs over benign LNs with the best outcomes from UPS_5.3. Detection of micro-metastatic LNs (cancer foci < 2 mm) remains a challenge. This study provides information on the detection of LN status for image-guided resection of metastatic LNs.

Local and Recurrent Regional Metastases of Melanoma

Up to 10% of patients with cutaneous melanoma will develop recurrent locoregional disease. While surgical resection remains the mainstay of treatment for isolated recurrences, locoregional melanoma can often present as bulky, unresectable disease and can pose a significant therapeutic challenge. This chapter focuses on the natural history of local and regionally recurrent metastases and the multiple treatment modalities which exist for advanced locoregional melanoma, including regional perfusion procedures such as hyperthermic isolated limb perfusion and isolated limb infusion, intralesional therapies, and neo-adjuvant systemic therapy strategies for borderline resectable regional disease. Hyperthermic limb perfusion (HILP) and isolated limb infusion (ILI) are generally well-tolerated and have shown overall response rates between 44% and 90%. Intralesional therapies also appear to be well-tolerated as adverse events are usually limited to the site of injection and minor transient flu-like symptoms. Systemic targeted therapies have shown to have response rates up to 85% when used as neoadjuvant therapy in patients with borderline resectable disease. While combination immunotherapy in the neoadjuvant setting has also shown promising results, this data has not yet matured.

The Role and Necessity of Sentinel Lymph Node Biopsy for Invasive Melanoma

Sentinel lymph node biopsy (SLNB) is a widely accepted procedure for melanoma staging and treatment. The development of lymphatic mapping and SLNB, which was first introduced in 1992, has enabled surgeons to detect microscopic nodal metastases and stage-negative regional nodal basins with low morbidity. SLNB has also facilitated the selective application of regional lymph node dissection for patients with microscopic nodal metastases, enabling unnecessary lymph node dissection. In contrast, recent major randomized phase III trials (DeCOG-SLT and MSLT–II trial) compared the clinical benefit of early completion lymph node dissection with observation after detecting microscopic nodal disease. The results of those studies indicated that there was no significant difference in the survival between the two groups, although regional control was superior after early completion lymph node dissection compared to that obtained after observation. Thus, the role and value of early completion lymph node dissection worldwide are currently very limited for patients with microscopic nodal disease. However, the use of SLNB is still controversial. In addition, the recent approval of adjuvant therapy using novel agents, such as anti-programmed death-1 antibodies, and molecular targeted therapeutics may influence the skipping of complete lymph node dissection in patients with micrometastatic nodal disease in a real-world setting. Furthermore, modern neoadjuvant therapy, which is now under investigation, may have the potential to change the surgical procedure used for nodal disease. Herein, we describe the current role and value of SLNB and completion lymph node dissection and discuss the major controversies as well as the favorable future outlook.

Lymphatic Mapping and Sentinel Lymph Node Biopsy in the Management of Primary Cutaneous Melanoma: Report of a Single-centre Experience

Aims and Background

Lymphatic mapping and sentinel lymph node biopsy provide important prognostic data in patients with early stage melanoma and are crucial in guiding the management of the tumor. We report our experience with lymphatic mapping and sentinel lymph node biopsy in a group of patients with primary cutaneous melanoma and discuss recent concepts and controversies on its use.

Patients and Methods

A total of 111 patients with stage I-II AJCC primary cutaneous melanoma underwent lymphatic mapping and sentinel lymph node biopsy from December 1999 through December 2004 using a standardized technique of preoperative lymphoscintigraphy and biopsy guided by blue dye injection in addition to a hand-held gamma probe. After removal, sentinel lymph nodes were submitted to serial sectioning and permanent preparations for histological and immunohistochemical examination. Complete lymph node dissection was performed only in patients with tumor-positive sentinel lymph nodes.

Results

Sentinel lymph nodes were identified and removed in all patients (detection rate of 100%), and metastases were found in 17 cases (15.3%). The incidence of metastasis in sentinel lymph nodes was 2.1%, 15.9%, 35.2%, and 41.6% for melanomas < or 1.0, 1.01-2.0, 2.01-4.0, and > 4.0 mm in thickness, respectively. Complete lymph node dissection was performed in 15 of 17 patients with positive sentinel lymph nodes, and metastases in non-sentinel lymph nodes were detected in only 2 cases (11.7%). Recurrences were more frequently observed in patients with a positive than in those with negative sentinel lymph node (41.1% vs 5.3% at a median follow-up of 31.5 months, P<0.001). The false-negative rate was 2.1%.

Conclusions

Our study confirms that lymphatic mapping and sentinel lymph node biopsy allow accurate staging and yield relevant prognostic information in patients with early stage melanoma.

External validation of a prognostic model to predict survival of patients with sentinel node-negative melanoma

Background

Identifying patients with sentinel node‐negative melanoma at high risk of recurrence or death is important. The European Organisation for Research and Treatment of Cancer (EORTC) recently developed a prognostic model including Breslow thickness, ulceration and site of the primary tumour. The aims of the present study were to validate this prognostic model externally and to assess whether it could be improved by adding other prognostic factors.

Methods

Patients with sentinel node‐negative cutaneous melanoma were included in this retrospective single‐institution study. The β values of the EORTC prognostic model were used to predict recurrence‐free survival and melanoma‐specific survival. The predictive performance was assessed by discrimination (c‐index) and calibration. Seeking to improve the performance of the model, additional variables were added to a Cox proportional hazards model.

Results

Some 4235 patients with sentinel node‐negative cutaneous melanoma were included. The median follow‐up time was 50 (i.q.r. 18·5–81·5) months. Recurrences and deaths from melanoma numbered 793 (18·7 per cent) and 456 (10·8 per cent) respectively. Validation of the EORTC model showed good calibration for both outcomes, and a c‐index of 0·69. The c‐index was only marginally improved to 0·71 when other significant prognostic factors (sex, age, tumour type, mitotic rate) were added.

Conclusion

This study validated the EORTC prognostic model for recurrence‐free and melanoma‐specific survival of patients with negative sentinel nodes. The addition of other prognostic factors only improved the model marginally. The validated EORTC model could be used for personalizing follow‐up and selecting high‐risk patients for trials of adjuvant systemic therapy.

Sentinel Lymph Node Biopsy in Small Papillary Thyroid Cancer: A Meta-analysis

PURPOSE

The aim of this study was to compare reported results on available techniques for sentinel lymph node detection rate (SDR) in papillary thyroid cancer (PTC).

METHODS

The MEDLINE database was searched via a PubMed interface to identify original articles regarding sentinel lymph node biopsy (SNB) in thyroid cancer. Studies were stratified according to the sentinel lymph node (SLN) detection technique: vital-dye (VD), Tc-nanocolloid planar lymphoscintigraphy with the use of intraoperative hand-held gamma probes (LS), both Tc-nanocolloid planar lymphoscintigraphy with intraoperative use of hand-held gamma probe and VD (LS + VD), Tc-nanocolloid planar lymphoscintigraphy with the additional contribution of preoperative SPECT/CT, and intraoperative use of hand-held gamma probe (LS-SPECT/CT). Pooled SDR values were presented with a 95% confidence interval (CI) for each SLN detection techniques. A Z-test was used to compare pooled SDR estimates. False-negative rates were summarized for each method.

RESULTS

Forty-five studies were included. Overall SDRs for the VD, LS, LS + VD, and LS-SPECT/CT techniques were 83% (95% CI, 77%-88%; I = 78%), 96% (95% CI, 90%-98%; I = 68%), 87% (95% CI, 65%-96%; I = 75%), and 93% (95% CI, 86%-97%; I = 0%), respectively. False-negative rates were 0% to 38%, 0% to 40%, 0% to 17%, and 7% to 8%, respectively.

CONCLUSIONS

In patients with PTC, Tc-nanocolloids offer a higher SDR than that of the VD technique. The addition of SPECT/CT improved identification of metastatic SLNs outside the central neck compartment.

Factors Affecting Growth Kinetics and Spontaneous Metastasis in the B16F10 Syngeneic Murine Melanoma Model

Melanoma is an immunogenic tumor that can metastasize quickly to proximal and distal sites, thus complicating the application of therapeutic modalities. Numerous mouse model systems have been used to gain understanding of the immunobiology and metastatic potential of melanoma. Here, we report the optimization of a syngeneic mouse melanoma model protocol using the mouse B16-derived melanoma cell line B16F10 that ensures the production of tumors on mice pinnae that are similar in size between animals and that enlarge in a time-dependent manner. In this model, B16F10 cells are first allowed to develop tumors after injection in the interscapular area or flank of C57BL/6J mice. Subsequently, the tumors are harvested, cells dissociated and injected into mouse pinnae. Dose-dependent studies revealed that injection of 2 × 10⁵ cells allowed for slow tumor enlargement, producing tumors averaging 100 mm³ within 2 to 3 wk with a metastatic frequency of 100%. This experimental protocol will be useful in dissecting the immunobiology of melanoma tumor development and metastasis and the evaluation of immunotherapeutic antimelanoma therapies.

Metastatic acral lentiginous melanoma in a tertiary referral center in Switzerland: a systematic analysis

Acral lentiginous melanoma (ALM) is a unique histopathological subtype of melanoma with a poorer prognosis than other cutaneous melanomas. This study aims to evaluate the clinicopathological characteristics, metastatic pattern, prognostic factors, response to systemic therapy, and overall survival (OS) of ALM in a White population. This is a retrospective study of patients who were diagnosed and/or treated for ALM at the Department of Dermatology of the University Hospital Zurich, Switzerland, from January 2005 to December 2015. Overall, 172 patients with histologically confirmed ALM were included in the study. In univariate Cox regression, Breslow thickness (P<0.001), age (P=0.003), status of sentinel lymph node (P=0.005), and ulceration (P=0.008) were identified as significant prognostic factors for OS in ALM. In multivariate analysis, only Breslow thickness (P=0.0003) showed statistical significance. The median OS (mOS) was 155.7 months in the entire cohort (n=172) and 11.2 months for stage IV patients (n=36), irrespective of treatment. When first treatment was considered (n=35), mOS for stage IV patients was 8.9, 16.6, 21.7, and 3.7 months, for patients who had received chemotherapy (ChT) (n=17), immunotherapy (n=9), targeted therapy (TT) (n=3), and no therapy (n=6), respectively. The overall response rate was 44% (7/16 patients) to ChT, 100% to TT (3/3), and 25% to ipilimumab (2/8). In our study, Breslow thickness represents the best prognostic factor for OS. In stage IV ALM patients treated with either immunotherapy or TT, there is a trend for extended mOS compared with ChT.

A model for predicting low probability of nonsentinel lymph node positivity in melanoma patients with a single positive sentinel lymph node

BACKGROUND

Identifying factors associated with nonsentinel lymph node (NSN) metastases in melanoma patients with a single positive sentinel lymph node (SLN) could aid decision making regarding adjuvant therapy. We describe a model for identifying patients with a single positive SLN at low risk for NSN metastasis.

METHODS

Factors associated with NSN metastasis in patients with a primary cutaneous melanoma and a single positive SLN who underwent completion lymph node dissection (CLND) were identified. These factors were used to construct a model for predicting the NSN status. The model was validated using a separate data set from another tertiary referral cancer center.

RESULTS

In the training data set, 111 patients had a single positive SLN. Of these, 27 had positive NSN. SLN tumor deposit diameter ≥0.75 mm (OR, 3.43; P = 0.047), age ≥40 (OR, 12.14; P = 0.024), and multifocal SLN tumor deposit location (OR, 4.16; P = 0.0096) were independently associated with NSN positivity. Patients with 0 to 1 of these risk factors had a low risk of NSN metastasis in both the training (7.5%) and validation (4.6%) data sets.

CONCLUSIONS

A combination of patient and SLN tumor burden characteristics can help to identify patients with a single positive SLN who are at a low risk of NSN metastasis.

Patterns of failure following the excision of in-transit lesions in melanoma and the influence of excisional margins

BACKGROUND AND OBJECTIVES

To describe the patterns of failure in patients with in-transit (IT) melanoma undergoing surgical excision.

METHODS

A retrospective review of patients who underwent their first IT lesion(s) resection between May 2005 and September 2014. Cumulative incidence of local failure (new lesion within 2 cm of IT resection) was estimated. Associations between clinicopathologic characteristics, local failure, and any recurrence were analyzed.

RESULTS

One hundred and thirty patients presented to our institution with IT disease over the study period and met the inclusion criteria. The 2-year cumulative incidence of local failure was 19.5%. Twenty-four patients developed disease within 2 cm of the resected IT disease; however, only eight were isolated local events. Cumulative incidence of local failure and of any disease differed with respect to less than 1 year disease-free interval (DFI) from primary melanoma to first IT event, and having greater than 1 IT lesion at presentation. Incidence of local failure was not found to differ with respect to gross margin greater than 5 mm, after adjusting for DFI and greater than 1 IT lesions.

CONCLUSIONS

Patients with greater than 1 IT lesion and a DFI less than 1 year are at a higher risk of failure after surgical excision of a first IT event. Very few failures were isolated local disease within 2 cm of the IT resection scar, regardless of IT excision margin.

Complete lymphadenectomy following positive sentinel lymph node biopsy in cutaneous melanoma: a critical review

Cutaneous melanoma is the solid neoplasia with the highest growing incidence among all tumors. It spreads predictably to the lymphatic vessels and sentinel lymph node, and when the latter is affected the prognosis worsens dramatically. Sentinel lymph node biopsy is considered when thickness of the primary tumor exceeds 1mm and/or when there are adverse features in thinner melanomas. When there is nodal metastasis, current evidence in the literature recommends complete lymphadenectomy, although this procedure has its intrinsic risks (i.e., lymphedema and cellulitis), and there are no published clinical trials proving additional overall survival benefits. The current in-depth literature review thus aims to identify patients that will benefit most from the procedure, including those with the highest likelihood of presenting additional affected lymph nodes in the same nodal basin. The authors also discuss techniques for identification of the sentinel lymph node, false-negative rates, and predictive models for lymph node involvement. In conclusion, complete elective lymphadenectomy should always be discussed on a case-by-case basis when metastases are detected in the sentinel lymph node.

Systematic review of sentinel lymph node biopsy in Merkel cell carcinoma of the head and neck

BACKGROUND

Merkel cell carcinoma (MCC) is a rare and aggressive cutaneous neuroendocrine tumor arising on the head and neck in 40%-50% of patients. Between 20% and 40% will harbor subclinical nodal metastasis.

METHODS

Using search terms 'Merkel AND sentinel', MEDLINE, PUMED, and EMBASE databases were systematically reviewed for publications regarding sentinel lymph node biopsy (SLNB) in classification I and II MCC of the head and neck.

RESULTS

Twenty-nine publications encompassing 136 patients were included. The SLNB finding was positive in 42 patients (30.9%). Primary MCC was located on the malar/zygomatic (34.4%), forehead/frontal (13.5%), and nasal (13.5%) regions. Recurrence in an SLNB negative nodal basin result occurred in 10 patients (false negative rate of 19.2%). Site of primary MCC was not associated with a false-negative SLNB result; however, there was a non-statistically significant trend for increased frequency among midline lesions.

CONCLUSIONS

Sentinel lymph node biopsy (SLNB) is recommended for eligible patients with classification I and II head and neck MCC.

Detection of melanoma metastases with the sentinel node biopsy: the legacy of Donald L. Morton, MD (1934-2014)

Dr. Donald L. Morton was clearly the pioneer of the sentinel node biopsy, which was a major advance in oncology that has improved the management of cancer patients worldwide. He conducted a series of practice-changing clinical trials to validate the important staging role of the sentinel lymph node biopsy for melanoma, and also spawned other studies that demonstrated its staging value in multiple other cancer types, most notably in breast cancer, gastric cancer, and colorectal cancer. His many contributions in this field have provided a unique opportunity to study host/tumor relationships, since the sentinel lymph node is the first location were the host immune defenses are confronted with metastasis arising from the primary cancer.

Tumour mutation status and melanoma recurrence following a negative sentinel lymph node biopsy

BACKGROUND

A proportion of patients develop recurrence following a tumour-negative sentinel lymph node biopsy (SLNB). This study aimed to explore whether melanoma patients with BRAF or NRAS mutant tumours have an increased risk of developing disease recurrence following a negative SLNB compared to patients with wild-type tumours.

METHODS

Prospective cohort study of melanoma patients at three tertiary referral centres in Melbourne, who underwent SLNB. Clinical, pathological and molecular characteristics and recurrence data were prospectively recorded. Multivariate Cox proportional hazards regression models estimated the adjusted hazard ratio (aHR) and corresponding 95% confidence interval (CI) for the association between mutation status and development of recurrence following a negative-SLNB.

RESULTS

Overall, 344/477 (72.1%) patients had a negative SLNB. Of these, 54 (15.7%) developed subsequent recurrence. The risk of disease recurrence following a negative SLNB was increased for patients with either a BRAF or NRAS mutant tumour compared to wild-type tumours (aHR 1.92, 95% CI: 1.02-3.60, p = 0.04).

CONCLUSION

Melanoma patients with BRAF or NRAS mutant tumours had an increased risk compared to patients with BRAF/NRAS wild-type tumours of developing disease recurrence following a tumour-negative SLNB. The findings also confirm the importance of continued surveillance to monitor for disease recurrence among SLNB-negative patients.

Analytic validity of DecisionDx-Melanoma, a gene expression profile test for determining metastatic risk in melanoma patients

BACKGROUND

The DecisionDx-Melanoma test provides prognostic information for patients with cutaneous melanoma (CM). Using formalin-fixed paraffin-embedded primary tumor tissue, the RT-PCR-based test classifies patients into a low- (Class 1) or high-risk (Class 2) category for recurrence based on expression of 31 genes. The current study was designed to assess the analytical validity of this test.

METHODS

Inter-assay, inter-instrument, and inter-operator studies were performed to evaluate reliability of the 31-gene expression test results, sample stability and reagent stability. From March 2013 through June 2016, the gene expression test was performed on 8244 CM tumors. De-identified data from Pathology Reports were used to assess technical success.

RESULTS

Robust sample and reagent stability was observed. Inter-assay concordance on 168 specimens run on 2 consecutive days was 99% and matched probability scores were significantly correlated (R² = 0.96). Inter-instrument concordance was 95%, and probability scores had a correlation R² of 0.99 (p < 0.001). From 8244 CM specimens submitted since 2013, 85% (7023) fulfilled pre-specified tumor content parameters. In these samples with sufficient tumor requirements, the technical success of the test was 98%.

CONCLUSION

DecisionDx-Melanoma is a robust gene expression profile test that demonstrates strong reproducibility between experiments and has high technical reliability on clinical samples.

18F-FDG PET/CT in the detection of asymptomatic malignant melanoma recurrence

Aim: To evaluate the diagnostic accuracy of FDG PET/CT in the detection of asymptomatic recurrence in patients with malignant melanoma who have had resection of their primary lesion. We also aimed to determine the pattern and factors predisposing to disease recurrence. Methods: Patients with malignant melanoma who have had surgical resection of their disease and without any clinical evidence of disease recurrence were followed- up with FDG PET/CT. The diagnostic accuracy of FDG PET/CT, pattern of recurrence and factors predictive of disease recurrence were determined. Results: A total of 144 patients were followed-up for a median period of 50.50 months. Asymptomatic recurrence was seen in 37 patients (25.7 %) with a median time to recurrence of 20 months. Lymph node was the commonest site of asymptomatic recurrence. Sex, tumour depth, histology type and presence of nodal metastasis were significant predictors of tumour recurrence. Age, race, site of primary lesion, type of lymph node resection were not significant predictors of disease recurrence. Race has a significant effect on the histological subtype of tumour (nodular maligna was more common in Caucasian while acral lentiginous was more prevalent in the Blacks) and the site of the primary lesion (lower limb in Blacks and trunk in Caucasians). Sensitivity, specificity and accuracy of FDG PET/CT for the detection of disease recurrence were 94.5 %, 87.6 % and 89.6 % respectively. Conclusion: FDG PET/CT is a suitable modality for early detection of asymptomatic recurrence of malignant melanoma. Asymptomatic recurrence most commonly occurs in lymph nodes. Sex, nodal metastasis and tumour pathologic features are predictors of recurrence.

Detection of Minimal Residual Disease and Its Clinical Applications in Melanoma and Breast Cancer Patients

Melanoma and breast cancer (BC) patients face a high risk of recurrence and disease progression after curative surgery and/or therapeutic treatment. Monitoring for minimal residual disease (MRD) during a disease-free follow-up period would greatly improve patient outcomes through earlier detection of relapse or treatment resistance. However, MRD monitoring in solid tumors such as melanoma and BC are not well established. Here, we discuss the clinical applications of MRD monitoring in melanoma and BC patients and highlight the current approaches for detecting MRD in these solid tumors.

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.

Frozen section analysis of SLNs in trunk and extremity melanoma has a high false negative rate but can spare some patients a second operation

OBJECTIVES

The purpose of this study was to evaluate the accuracy of frozen section (FS) analysis of sentinel lymph nodes (SLN) in melanoma.

METHODS

Five hundred seventy-one patients underwent FS analysis of SLN between 1/2000 and12/2010. Surgical and pathological characteristics, recurrence, and survival were analyzed. Comparisons were made using χ² and Fisher's exact t-test.

RESULTS

One hundred thirty-three (23%) patients were SLN positive of which 63 (47.4%) were identified on FS. 16/70 SLN metastases not identified on FS (23%) were seen only on immunohistochemistry. FS analysis detected 84% of SLN metastasis >2 mm. SLN FS false negative rate was 53%, positive predictive value 100%, negative predictive value 88%, and overall accuracy 89%. Among patients with a FS positive SLN, 17/63 (27%) had additional positive nodes on CLND, versus 1 of 70 (1.4%) with a positive SLN identified only on permanent section pathology (P < 0.0001). The nodal recurrence rate following a negative SLN biopsy was 5%.

CONCLUSIONS

FS analysis for SLNs spared approximately half of patients a second operation. Patients with a positive SLN detected on FS were more likely to have further nodal involvement. In our experience intraoperative pathologic analysis of melanoma SLNs does not impair our ability to detect SLN metastasis or lead to a high rate of false positive results or nodal recurrences. J. Surg. Oncol. 2016;114:879-883. © 2016 2016 Wiley Periodicals, Inc.

Nodular Histologic Subtype and Ulceration are Tumor Factors Associated with High Risk of Recurrence in Sentinel Node-Negative Melanoma Patients

Background

Since its introduction, the sentinel lymph node biopsy (SLNB) has become the standard staging procedure in clinical node-negative melanoma patients. A negative SLNB, however, does not guarantee a recurrence-free survival. Insight into metastatic patterns and risk factors for recurrence in SLNB negative melanoma patients can provide patient tailored guidelines.

Methods

Data concerning melanoma patients who underwent SLNB between 1996 and 2015 in a single center were prospectively collected. Cox regression analyses were used to determine variables associated with overall recurrence and distant first site of recurrence in SLNB-negative patients.

Results

In 668 patients, SLNBs were performed between 1996 and 2015. Of these patients, 50.4 % were male and 49.6 % female with a median age of 55.2 (range 5.7–88.8) years. Median Breslow thickness was 2.2 (range 0.3–20) mm. The SLNB was positive in 27.8 % of patients. Recurrence rates were 53.2 % in SLNB-positive and 17.9 % in SLNB-negative patients (p < 0.001). For SLNB-negative patients, the site of first recurrence was distant in 58.5 %. Melanoma located in the head and neck region (hazard ratio 4.88, p = 0.003) and increasing Breslow thickness (hazard ratio 1.15, p = 0.013) were predictive for distant first site of recurrence in SLNB-negative patients. SLNB-negative patients with a nodular melanoma and ulceration had a recurrence rate of 43.1 %; the site of recurrence was distant in 64 % of these patients.

Conclusions

The recurrence rates of SLNB-negative nodular ulcerative melanoma patients approach those of SLNB-positive patients. Stringent follow-up is recommended in this subset of patients.

Adjusted Hospital Sentinel Lymph Node Positivity Rates in Melanoma: A Novel Potential Measure of Quality

OBJECTIVE

Our objectives were to examine whether hospital characteristics are associated with lower- and higher-than-expected sentinel lymph node biopsy (SLNB) positivity rates and whether hospitals with lower- or higher-than-expected SLNB positivity rates have worse patient outcomes.

BACKGROUND

Surgeon and pathologist SLNB technical errors may lead to incorrect melanoma staging. A hospital's SLNB positivity rate may reflect its SLNB proficiency for melanoma, but this has never been investigated.

METHODS

Stage IA-III melanoma patients undergoing SLNB were identified from the National Cancer Data Base (2004-2010). Hospital-level SLNB positivity rates were adjusted for patient- and tumor factors. Hospitals were divided into terciles of adjusted SLNB positivity rates. Hospital characteristics (using multinomial logistic regression) and survival (using Cox modeling) were examined across terciles.

RESULTS

Of 33,639 SLNB patients (from 646 hospitals), 2916 (8.7%) had at least 1 positive lymph node. Hospitals with lower- (low tercile) and higher-than-expected (high tercile) SLNB positivity rates were more likely to be low-volume hospitals (low tercile: relative risk ratio (RRR) = 2.57, P = 0.002; high tercile: RRR = 2.3, P = 0.004) compared to hospitals with expected rates (middle tercile). Stage I patients treated at lower-than-expected SLNB positivity rate hospitals had worse 5-year survival than those treated at expected SLNB positivity rate hospitals (90.0% vs 91.9%, P = 0.014; hazard ratio = 1.28, 95% CI: 1.05-1.57); survival differences were not observed by SLNB positivity rates for stage II/III.

CONCLUSIONS

Adjusted hospital SLNB positivity rates varied widely. Surgery at hospitals with lower-than-expected SLNB positivity rates was associated with decreased survival. Hospital SLNB positivity rates may be a novel measure to confidentially report to hospitals for internal quality assessment.

Lymph nodes and the melanoma surgeon: re-defining a long-term relationship

Surgeons now have an enhanced ability to stage patients with clinically localized cutaneous melanoma using sentinel lymph node biopsy. Despite this, the weight of clinical evidence is tilting in favor of a measured approach to pre-emptive lymph node removal. Careful consideration of whether traditional surgical approaches to the regional nodes, whether done in the name of 'staging' or pre-emptive removal of a potential site of relapse, really 'benefit' the patient is paramount for optimal care.