The role of sentinel lymph node biopsy for melanoma: evidence assessment

A bibliometric analysis of sentinel lymph node biopsy in melanoma of the top 90 cited publications

BACKGROUND

This bibliometric analysis aims to describe research trends and assess the methodological quality of the highest-impact SLNB research in melanoma.

METHODS

We identified the 90 most cited publications on SLNB in melanoma using Web of Science, covering all available journal years (from 2005 to date). The Oxford Center for Evidence-Based Medicine (OCEBM) Levels of Evidence (LOE) were used to assess the methodological quality of each study.

RESULTS

The 90 most cited publications on SLNB in melanoma collectively garnered 10,314 citations. Citation counts per publication ranged from 44 to 1,405 (mean 114.6 ± 185.2), with the highest-cited study authored by Professor Donald Morton et al. The majority of publications was classified as LOE 3 (n = 36). The United States of America (USA) led in publication output with 43 articles. Professors Merrick Ross (USA) and John Thompson (Australia) were the leading authors by publication count. The University of Sydney (Australia), University of Texas System, and Anderson Cancer Center (USA) were the top contributing institutions. Annals of Surgical Oncology published most articles.

CONCLUSIONS

This bibliometric analysis provides a comprehensive overview and valuable reference for future researchers in the field of SLNB in melanoma.

An Evaluation of Sentinel Lymph Node Biopsy Guideline Adherence in Melanoma

BACKGROUND

Regional lymph nodes are a common first site of metastasis in patients diagnosed with invasive melanoma. Knowledge of sentinel lymph node status provides strong prognostic information in melanoma and is important for staging and treatment decisions. The National Comprehensive Cancer Network® (NCCN) recommends performance of sentinel lymph node biopsy (SLNB) for melanoma patients with a T category of ≥T2a. This study aims to assess our academic institution's guideline adherence to improve quality of care.

METHODS

Retrospective review of medical records from 2017 to 2023 identified 628 patients referred to our institution for invasive melanoma treatment. Adherence to guidelines was assessed using Chi-square analyses and Fisher's exact tests.

RESULTS

In total, 8.2% of cases did not follow the NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines®) for SLNB. When justification provided within the medical record was considered adherent to guidelines, our rate of discordance was 1.6%. Head and neck melanomas were more likely to have guideline-discordant SLNB management, regardless of whether or not a justification was provided.

CONCLUSION

Greater than 98% of melanoma cases at our institution aligned with the SLNB NCCN Guidelines®. We outlined the complex justifications physicians and patients may use to pursue care that is nonadherent to guidelines. Employment of SLNB may be limited by medical comorbidities, surgical risks, and when the management would not change based on the result. Our study provides a blueprint for institutional assessment of guideline adherence and highlights the importance of documentation and guideline dissemination.

The efficacy of 99mTc-rituximab as a tracer for sentinel lymph node biopsy in cutaneous melanoma patients

Background

The sentinel lymph node (SLN) status is a vital prognostic factor for malignant melanoma (MM) patients. There is increasing evidence that a radioactive agent, rather than its combination with blue dye, is sufficient for a SLN biopsy (SLNB). Thus, we discussed the efficacy of ^99mTc-rituximab as a tracer in MM patients.

Methods

A total of 502 consecutive patients with MM who underwent SLNB were enrolled in this study. All participants were peritumorally injected with ^99mTc-rituximab before imaging, and scanned with single-photon emission computed tomography-computed tomography (SPECT-CT) to detect the number and location of the SLN. A gamma detection probe was employed to detect radioactive SLNs in operation. Follow up was conducted to observe whether nodal or distant recurrence occurred.

Results

The SLNs were successfully imaged via SPECT-CT and harvested from all 502 participants. No drainage tube was indwelled and 32 (6.3%) participants experienced the following complications: seroma (n=26, 5.2%), wound infections or lymphangitis (n=6, 1.2%), sensory nerve injuries (n=4, 0.8%). There were 380 patients who were diagnosed as SLN-negative and 122 (24.2%) were SLN-positive. A total of 85 SLN-positive patients received complete lymph node dissection, and 28 (32.9%) had additional positive lymph nodes. During a median follow-up of 24 months, 28 participants were found to have a false negative (FN) SLN. The FN rate was 18.7%. A higher T stage was a predictive factor for FN [odds ratio (OR) 1.77; P<0.05]. There was no significant difference in the positive or FN rate between the acral and cutaneous groups.

Conclusions

The radiopharmaceutical ^99mTc-rituximab could be employed as a simple and safe tracer in acral and cutaneous melanoma SLN biopsies.

Five-year survival in patients with nodular and superficial spreading melanomas in the US population

BACKGROUND

Although superficial spreading melanomas (SSM) are diagnosed as thinner lesions, nodular melanomas (NM) have a more rapid growth rate and are biologically more aggressive compared with other histologic subtypes.

OBJECTIVE

To determine the difference in 5-year relative survival in patients with NM and SSM at the same Breslow depth and TNM stage.

METHODS

A population-based cross-sectional analysis compared the 5-year relative survival of patients with NM and SSM using data from the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER)∗Stat software (version 8.2.1-8.3.5). Chi-square tests compared the proportions, and Kaplan-Meier method with Z-score compared 5-year relative survival.

RESULTS

For patients receiving a diagnosis between 2004 and 2009, 5-year relative survival was lower in NM compared with SSM (53.7% vs 87.3%; Z score, -41.35; P < .001). Similarly, for patients receiving a diagnosis between 2010 and 2015, 5-year relative survival was lower in NM compared with SSM (61.5% vs 89.7%; Z score, -2.7078; P < .01). Subgroup analyses showed inferior survival in NM in T1b, and survival differences remained significant after excluding patients with nodal or distant metastases.

CONCLUSIONS

Five-year relative survival is worse in NM compared with SSM especially in T1b, T2a, and T2b melanomas. Melanoma subtype should be taken into consideration when making treatment recommendations.

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

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

Pediatric melanoma

Childhood melanoma is a rare pediatric malignancy, with fewer than 500 new diagnoses annually. The incidence is increasing, particularly in the adolescent population. This review highlights the epidemiology, clinical presentation, and histopathologic challenges of pediatric melanoma. Surgical resection remains the cornerstone for localized and regionally advanced disease. Adjuvant therapies, including current options and potential novel therapeutics for this unique population will be discussed.

Clinical utilities and biological characteristics of melanoma sentinel lymph nodes

An estimated 73870 people will be diagnosed with melanoma in the United States in 2015, resulting in 9940 deaths. The majority of patients with cutaneous melanomas are cured with wide local excision. However, current evidence supports the use of sentinel lymph node biopsy (SLNB) given the 15%-20% of patients who harbor regional node metastasis. More importantly, the presence or absence of nodal micrometastases has been found to be the most important prognostic factor in early-stage melanoma, particularly in intermediate thickness melanoma. This review examines the development of SLNB for melanoma as a means to determine a patient’s nodal status, the efficacy of SLNB in patients with melanoma, and the biology of melanoma metastatic to sentinel lymph nodes. Prospective randomized trials have guided the development of practice guidelines for use of SLNB for melanoma and have shown the prognostic value of SLNB. Given the rapidly advancing molecular and surgical technologies, the technical aspects of diagnosis, identification, and management of regional lymph nodes in melanoma continues to evolve and to improve. Additionally, there is ongoing research examining both the role of SLNB for specific clinical scenarios and the ways to identify patients who may benefit from completion lymphadenectomy for a positive SLN. Until further data provides sufficient evidence to alter national consensus-based guidelines, SLNB with completion lymphadenectomy remains the standard of care for clinically node-negative patients found to have a positive SLN.

Sentinel lymph node biopsy for melanoma: is there a correlation of preoperative lymphatic mapping with sentinel lymph nodes harvested?

BACKGROUND

Nodal status is the most significant prognostic factor in melanoma. No study has examined the relationship between lymphoscintigraphy, γ probe counts, harvested nodes, and nodal status.

METHODS

Two-hundred sixty two patients were identified who underwent sentinel lymph node biopsy for melanoma between 2001 and 2010. Clinicopathologic and treatment information was collected. The number of lymph nodes and basins demonstrated on lymphoscintigraphy was compared to those at surgery. γ Probe counts were compared.

RESULTS

Median age was 54.5 years (range, 18-90 years) with 52.3% male. Average Breslow depth was 2.0 (1.9) mm; 99.6% of lymphoscintigraphy studies identified at least 1 basin, 80% showed only 1 (range, 0-4). Lymphoscintigraphy identified on average 1.5 (0.9) sentinel nodes and 31% with secondary node. Surgery excised on average 2.6 (1.4) nodes involving 1.2 (0.5) basins; 17.6% had a positive sentinel lymph node. There was no difference in the sum or average of γ counts between positive and negative sentinel lymph node groups (P = 0.2, P = 0.5). When comparing lymphoscintigraphy and surgical excision, the correlation of lymphatic basins was r = 0.67 and of lymph node numbers was r = 0.33.

CONCLUSIONS

Lymphoscintigraphy should be used to identify the proper lymphatic basins for a sentinel node procedure, however, the removal of nodes must continue until the background count is less than 10%. The correlation of lymph node number identified on lymphoscintigraphy to surgical excision is weak. γ Probe counts cannot be used to differentiate positive from negative nodes and the positive lymph node is not always the hottest node.

Squamous cell carcinoma of the hand: a 20-year review

PURPOSE

Squamous cell carcinoma (SCC) is a common malignancy of the hand; yet, recurrence rates, metastatic rates, and long-term survival rates have not been well defined. This study evaluated the risk factors for local and regional recurrence for this diagnosis.

METHODS

Records of patients treated for SCC of the hand over a 20-year period in a single institution were reviewed. Data collected included patient demographics, tumor characteristics, and preoperative and postoperative care received. Overall survival, recurrence-free survival, and survival free of SCC in the same upper extremity were analyzed.

RESULTS

A total of 86 patients were identified. Mean age at the time of initial presentation was 69 years (range, 39-89 y). Mean follow-up was 6.4 years (range, 1-15 y). Overall survival was 88% and 57% at 5 and 10 years, respectively. Recurrence-free survival was 67% and 50% at 5 and 10 years, respectively. Rate of metastasis was 4%. Lymph node biopsy was performed in 4 patients who had clinical lymphadenopathy; 2 patients had positive nodes. Average time to first recurrence was 4.1 years (range, 0.5-11 y). Web space location, bilateral tumors, multiple tumors, and prior history of SCC were associated with an increased risk of recurrence. Survival free of SCC in the same upper extremity was 72% and 54% at 5 and 10 years, respectively. Younger age, history of transplantation, multiple tumors, and use of flap or skin graft for closure were associated with an increased risk of another SCC developing in the same extremity. No benefit was noted with wide, Mohs, or shave resection in terms of overall survival, recurrence-free survival, or SCC occurrence in the ipsilateral upper extremity.

CONCLUSIONS

Squamous cell carcinoma tumors of the hand have a high tendency for local recurrence but a low rate of metastasis. Specific characteristics of the tumor may increase chances of recurrence. The technique of tumor excision did not have a major role in outcome.

TYPE OF STUDY/LEVEL OF EVIDENCE

Prognostic IV.

Guidelines of care for the management of primary cutaneous melanoma. American Academy of Dermatology

The incidence of primary cutaneous melanoma has been increasing dramatically for several decades. Melanoma accounts for the majority of skin cancer-related deaths, but treatment is nearly always curative with early detection of disease. In this update of the guidelines of care, we will discuss the treatment of patients with primary cutaneous melanoma. We will discuss biopsy techniques of a lesion clinically suspicious for melanoma and offer recommendations for the histopathologic interpretation of cutaneous melanoma. We will offer recommendations for the use of laboratory and imaging tests in the initial workup of patients with newly diagnosed melanoma and for follow-up of asymptomatic patients. With regard to treatment of primary cutaneous melanoma, we will provide recommendations for surgical margins and briefly discuss nonsurgical treatments. Finally, we will discuss the value and limitations of sentinel lymph node biopsy and offer recommendations for its use in patients with primary cutaneous melanoma.

Acral lentiginous melanoma: a case control study and guidelines update

Background. Malignant melanoma incidence is increasing dramatically. We report herein a case of the rarest acral lentiginous type. Case Report. A 58-year-old man presented with a melanoma resembling lesion over the sole of his right foot, measuring 15-20 mm in diameter. An excisional biopsy with a narrow (2 mm) margin of surrounding skin was obtained. Histological findings were consistent with a diagnosis of acral lentiginous melanoma. Sentinel lymph node biopsy was also performed and micrometastases were not identified in frozen-section examination. According to the AJCC system, the tumor stage was IB (T2aN0M0). A wide local excision of the biopsy scar with a margin of 2 cm was performed. A split-thickness thick skin graft was used to reconstruct the excisional defect. During an 18-month followup, no local or distant recurrence has been observed. This paper aims to extract an updated rational approach to the management of this disease out of an enormous body of knowledge.

AJCC melanoma staging update: impact on dermatopathology practice and patient management

Changes in the 2010 American Joint Commission on Cancer melanoma staging guidelines include the evaluation of primary tumor mitotic index (mitogenicity) and the recognized prognostic significance of a single melanoma cell in a sentinel lymph node. These revised criteria have important practice implications for dermatopathologists as well as for dermatologists, oncologists and surgeons who treat patients with cutaneous melanoma.

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.

Modification of lymphoscintigraphic sentinel node identification before and after excisional biopsy of primary cutaneous melanoma

The aim of this study was to determine whether excision biopsy and primary closure of primary cutaneous melanoma modifies lymphatic drainage and accuracy of sentinel node biopsy. Thirty patients with 31 cutaneous melanomas were prospectively enrolled to undergo lymphoscintigraphy (LS) before and after excision biopsy. Tc-human serum albumin nanocolloid was first injected intradermally around the primary tumor and subsequently, after excision biopsy, adjacent to the scar. Sentinel nodes were identified by preoperative LS and the gamma-probe. Patent Blue V dye was injected intraoperatively before sentinel node biopsy. Intraoperative sentinel node identification was 100%. In 23 of 31 cases, both LSs were concordant in terms of nodal basins visualized. Two patients had a basin downstaged and six patients had a basin upstaged by the second LS. Only 50% of LS hot nodes stained blue (42 of 84). In 24 of 31 cases, the sentinel node was negative for metastases. Seven patients underwent complete lymph node dissection because of sentinel node positivity. Only one patient had metastases also to a non-sentinel node. After a median follow-up of 30 months lymph node metastases have not been observed in the eight discordant cases. This study shows that sentinel node identification and biopsy after lymphatic mapping is accurate after excision biopsy of primary cutaneous melanoma. Excision biopsy may, however, modify lymphatic drainage and a narrow excision margin should be performed if melanoma is suspected.

Sentinel lymph node biopsy for high-risk nonmelanoma skin cancers

BACKGROUND

Although the utility of the sentinel lymph node biopsy (SLNB) in the staging of melanoma is well established, its usefulness in high-risk nonmelanoma skin cancer (NMSC) is yet to be determined.

OBJECTIVE

The objective was to report our experience with patients who underwent SLNB for the staging of a high-risk NMSC.

MATERIALS AND METHODS

We identified 13 patients with a high-risk NMSC who underwent SLNB between 1998 and 2006 and conducted a retrospective review of their medical records and tumor pathology. Their status as regards tumor recurrence and survival was obtained when possible.

RESULTS

Of 13 patients, 9 had squamous cell carcinoma (SCC), 2 had sebaceous gland carcinoma, 1 had porocarcinoma, and 1 had atypical fibroxanthoma. All SLNB were negative for metastatic disease, but 1 appeared to be a false-negative finding.

CONCLUSION

Compared to melanoma, SCC of the skin are much less predictable as regards their tendency to metastasize to the regional lymph nodes. Although the SLNB appears to be a reliable staging procedure for NMSC (especially SCC), the yield may be too low to justify its routine use in this patient population. More data are needed to determine when a SLNB is justified in the management of NMSC.

Sentinel lymph node biopsy in patients with thick (= 4 mm) melanoma: a single-centre experience

BACKGROUND AND OBJECTIVE

Lymphatic mapping/sentinel lymph node biopsy (LM/SLNB) have become routine techniques for staging the regional lymph nodes in early stage melanoma, yet their role in the management of thick (= 4 mm) melanoma is debated. The aim of the present study is to review our experience with LM/SLNB in a series of patients with thick primary melanoma, to evaluate its utility in this melanoma subset.

PATIENTS AND METHODS

Thirty patients (18 men and 12 women; mean age 70.6 years; median 75 years) with thick primary melanoma underwent LM/SLNB, using both radioisotope and blue dye. The statistical tests were performed by using SAS software for Windows, version 8.2.

RESULTS

The primary tumour sites were head/neck (n = 5; 16.6%), trunk (n = 10; 33.3%), and extremities (n = 15; 50%). Tumour thickness ranged from 4 to 17 mm (mean 5.14 mm; median 4.5 mm). Ulceration was observed in 23 (76.6%) tumours. Eleven patients (36.6%) had at least a positive sentinel lymph node (SLN). The mean follow-up was 27.3 months (median 26 months; range 5-63 months). Patients without SLN metastases had a 5-year disease-free survival rate of 78.9%, vs. 18.2% for patients with SLN metastases (P = 0.0121 by log rank test). The 5-year overall survival rate for patients without SLN metastases was 89.5%, whereas patients with SLN metastases had a 5-year overall survival rate of 36.4% (P = 0.0272 by log rank test).

CONCLUSION

Our retrospective analysis indicates that the SLN status is predictive of recurrence and survival in patients with thick melanoma, and LM/SLNB should be routinely performed in this subset of melanoma patients.

Current surgical management of melanoma

The surgical management of melanoma has changed dramatically over the last few decades. Through the development and conduction of well-designed, prospective, randomized trials, we have been able to refine the way that we surgically manage patients with melanoma. Indeed, many important issues have been addressed through such trials: the proper surgical margins for the primary melanoma, utility of the elective lymph node dissection and the role for selective lymphadenectomy, to name a few. This review will also discuss what we have learned from past clinical trials and address several issues with regards to where we are going in the future.

The impact of factors beyond Breslow depth on predicting sentinel lymph node positivity in melanoma

BACKGROUND

In addition to Breslow depth, the authors previously described how increasing mitotic rate and decreasing age predicted sentinel lymph node (SLN) metastases in patients with melanoma. The objectives of the current study were to verify those previous results and to create a prediction model for the better selection of which patients with melanoma should undergo SLN biopsy.

METHODS

The authors reviewed 1130 consecutive patients with melanoma in a prospective database who underwent successful SLN biopsy. After eliminating patients aged <16 years and patients who had melanomas that measured <1 mm, 910 remaining patients were reviewed for clinical and pathologic features and positive SLN status. Univariate association of patient and tumor characteristics with positive SLN status was explored by using standard logistic regression techniques, and the best multivariate model that predicted lymph node metastases was constructed by using a backward stepwise-elimination technique.

RESULTS

The characteristics that were associated significantly with lymph node metastasis were angiolymphatic invasion, the absence of regression, increasing mitotic rate, satellitosis, ulceration, increasing Breslow depth, decreasing age, and location (trunk or lower extremity compared with upper extremity or head/neck). Previously reported interactions between mitotic rate and age and between Breslow depth and age were confirmed. The best multivariate model included patient age (linear), angiolymphatic invasion, the number of mitoses (linear), the interaction between patient age and the number of mitoses, Breslow depth (linear), the interaction between patient age and Breslow depth, and primary tumor location.

CONCLUSIONS

Younger age, increasing mitotic rate (especially in younger patients), increasing Breslow depth (especially in older patients), angiolymphatic invasion, and trunk or lower extremity location of the primary tumor were associated with a greater likelihood of positive SLN status. The current results support the use of factors beyond Breslow depth to determine the risk of positive SLN status in patients with cutaneous melanoma.

Significance of multiple lymphatic basin drainage in truncal melanoma patients undergoing sentinel lymph node biopsy

BACKGROUND

Truncal melanoma involving metastases to multiple lymph node basins has a much worse prognosis than tumor involvement of a single lymph node basin. Recent results also suggest that, independently of the status of lymph node involvement, patients with multiple lymphatic basin drainage (MLBD) on lymphoscintigraphy have an increased risk of lymph node metastasis and a worse prognosis than those with a single lymphatic drainage basin. Because published reports have conflicting results, the authors compared their experience at the University of Michigan Comprehensive Cancer Center with recently published findings.

METHODS

The authors searched a prospectively maintained melanoma database at the University of Michigan for patients with primary truncal melanoma who underwent lymphoscintigraphy and sentinel lymph node biopsy between 1997 and 2004. The association of MLBD with the clinical and pathologic characteristics collected and the presence of regional metastases was tested by using contingency tables and the chi(2) test statistic and by using the Fisher's exact test statistic when cell frequencies were small. The product-limit method of Kaplan and Meier was used to estimate disease-free and overall survival probabilities.

RESULTS

Of 423 patients with primary truncal melanoma who underwent sentinel lymph node biopsy, 123 (29%) had a positive result, and 98 patients (23.2%) had MLBD. Patients with tumors located in the middle of the trunk and tumor ulceration were more likely to have MLBD (P < .0001 and P = .045, respectively). Patients with a single lymphatic drainage basin and MLBD had a similar risk of lymph node metastasis and similar disease-free and overall survival.

CONCLUSIONS

Patients with truncal melanomas tend to have MLBD when the tumor is located in the middle of the trunk or when ulceration is present. In our experience, drainage to multiple lymphatic basins was not an independent risk factor for sentinel lymph node metastasis and has no independent prognostic significance.