Sentinel Lymph Node Biopsy and Completion Lymph Node Dissection for Melanoma

Review on Lymph Node Metastases, Sentinel Lymph Node Biopsy, and Lymphadenectomy in Sarcoma

Soft tissue sarcomas (STS) originating from connective tissue rarely affect the lymph nodes. However, involvement of lymph nodes in STS is an important aspect of prognosis and treatment. Currently, there is no consensus on the diagnosis and management of lymph node metastases in STS. The key risk factor for nodal involvement is the histological subtype of sarcoma. Radiological and pathological evaluation seems to be the most effective method of assessing lymph nodes in these neoplasms. Thus, sentinel lymph node biopsy (SLNB), which has been shown to be valuable in the management of melanoma or breast cancer, may also be a beneficial diagnostic option in some high-risk STS subtypes. This review summarizes data on the risk factors and clinical characteristics of lymph node involvement in STS. Possible management and therapeutic options are also discussed.

Variability of Sentinel Lymph Node Location in Patients with Trunk Melanoma

(1) Background: Melanoma is one of the most aggressive types of neoplasia, and the management of this pathology requires a correct staging, as well as a personalized modern oncological treatment. The main objective of the study is to determine the variability of the lymphatic drainage for patients with melanomas located on the trunk and, secondarily, to determine the features of individuals who underwent sentinel lymph node biopsy (SLNB) depending on the exact location on the trunk. (2) Methods: This retrospective, observational, single-center study included 62 cases of trunk melanoma operated between July 2019 and March 2023, in which SLNB was performed and a total of 84 lymph nodes were excised. (3) Results: Patients had a median age of 54.5 (33-78) years, with 58.1% being male; the melanomas had a median Breslow index of 2.3 (0.5-12.5) mm. Approximately 64.3% of the cohort had melanoma on the upper part of the trunk (54 cases) and 35.7% had it on the lower part (30 cases). The type of anesthesia chosen was general anesthesia in 53 cases and spinal anesthesia in 9 cases (85.5% vs. 14.5%, p < 0.001). The number of sentinel lymph nodes excised was 54 for melanomas located on the upper part of the trunk (8 cervical and 46 axillary) and 30 sentinel lymph nodes for melanomas of the lower part of the trunk (16 at the axillary level and 14 at the inguinal level). Out of the 54 LNs identified in patients with melanoma on the upper part of the trunk, 13 were positive, with a total of 12 positive lymph nodes (LNs) from the axillar basin, and only one from the cervical region. Additionally, the incidence of patients with a minimum of two identified sentinel lymph nodes was 32.2%, with a total of seven having LN involvement in two basins, and only one of these cases showed positivity for malignancy. (4) Conclusions: SLNBs were more frequent in the axillary region overall, and had more positive SLNs. Moreover, melanoma on the upper part of the trunk had a higher rate of positive SLNs compared to the lower part. Tumors located on the lower part of the truck had more positive SLNs in the axillary region than in the inguinal one.

Clinical Outcomes and Prognostic Factors of Patients With Early Malignant Melanoma in One Latin American Country: Results of the Epidemiological Registry of Malignant Melanoma in Colombia Study

To describe the population with early malignant melanoma, we performed a cohort study on the basis of the Epidemiological Registry of Malignant Melanoma in Colombia-Asociacion Colombiana de Hematologia y Oncologia. From January 2011 until December 2021, 759 patients were included; the average age was 66 years, 57% were women, acral lentiginous histology was found in 27.8% of patients, and the median follow-up was 36.5 months. The prognostic factors for overall survival in our population are Eastern Cooperative Oncology Group 3-4 (hazard ratio [HR], 13.8), stage III (HR, 5.07), received radiotherapy (HR, 3.38), ulceration on histology (HR, 2.68), chronic sun exposure (HR, 2.3), low income (HR, 2.04), previous local surgery (HR, 0.27), and have received adjuvant treatment (HR, 0.41).

The Characteristics of Sentinel Lymph Node Biopsy in Cutaneous Melanoma and the Particularities for Elderly Patients-Experience of a Single Clinic

BACKGROUND

Melanoma is a malignant tumor that determines approximately 80% of deaths as skin cancer-related. The sentinel lymph node (SLN) represents the first filter of tumor cells toward systemic dissemination. The primary objective was to outline the surgical specifics of the sentinel lymph node biopsy (SLNB) technique, correlate the location of the lymph node with the radiotracer load, and identify the characteristics of older patients.

METHODS

In this prospective study, 122 cases of malignant melanoma needing SLNB technique were included, between June 2019 and November 2022, resulting in 162 lymph nodes removed.

RESULTS

Patients' mean age was 54.3 ± 14.4 years old, the prevalence of 70 years and older being 20.5%. The rate of positive SLN was 24.6%, with a single drainage in 68.9% of cases. The frequency of seroma was 14.8%, while reintervention 1.6%. The inguinal nodes had the highest preoperative radiotracer load (p = 0.015). Patients 70 years old or older had significantly more advanced-stage melanoma (68.0% vs. 45.4%, p = 0.044, OR = 2.56) and a higher rate of positive SLN (40.0% vs. 20.6%, p = 0.045,OR = 2.57). Melanoma of the head and neck was more common among older individuals (32.0% vs. 9.3%, p = 0.007,OR = 4.60).

CONCLUSIONS

The SLNB has a low rate of surgical complications and the positivity of SLN is not related to radiotracer load. Elderly patients are at risk for head and neck melanoma, have more advanced stages, a higher SLN positivity, and a greater rate of surgical complications.

Melanoma lymph node metastases - moving beyond quantity in clinical trial design and contemporary practice

The presence of lymph node metastases is a well-studied prognostic factor for cutaneous melanoma. Characterization of melanoma lymph node metastases and their association with survival in multiple, large observational studies has led to recognition of the following high-risk features: quantity of lymph node metastases (number of nodes), size of the nodal tumor deposit (in mm), and extracapsular extension. Despite increasing utilization of these features in the design of randomized clinical trials, in addition to their role in contemporary clinical decision-making, current staging systems lag behind, only accounting for the quantity of lymph nodes with metastases. Herein, we review the prognostic role of melanoma lymph node metastases and their high-risk features, current reporting standards, how such features have been utilized in practice-changing trials, and best practices for future clinical trial design and clinical decision-making.

Spatial biology analysis reveals B cell follicles in secondary lymphoid structures may regulate anti-tumor responses at initial melanoma diagnosis

Introduction

B cells are key regulators of immune responses in melanoma. We aimed to explore differences in the histologic location and activation status of B cell follicles in sentinel lymph nodes (SLN) of melanoma patients.

Methods

Flow cytometry was performed on fresh tumor draining lymph nodes (LN). Paraffin slides from a separate cohort underwent NanoString Digital Spatial Profiling (DSP)®. After staining with fluorescent markers for CD20 (B cells), CD3 (T cells), CD11c (antigen presenting cells) and a nuclear marker (tumor) was performed, regions of interest (ROI) were selected based on the location of B cell regions (B cell follicles). A panel of 68 proteins was then analyzed from the ROIs.

Results

B cell percentage trended higher in patients with tumor in LN (n=3) compared to patients with nSLN (n=10) by flow cytometry. B cell regions from a separate cohort of patients with tumor in the (pSLN) (n=8) vs. no tumor (nSLN) (n=16) were examined with DSP. Within B cell regions of the SLN, patients with pSLN had significantly higher expression of multiple activation markers including Ki-67 compared to nSLN patients. Among 4 patients with pSLN, we noted variability in arrangement of B cell follicles which were either surrounding the tumor deposit or appeared to be infiltrating the tumor. The B cell follicle infiltrative pattern was associated with prolonged recurrence free survival.

Conclusion

These data suggest a role for B cell follicles in coordinating effective adaptive immune responses in melanoma when low volume metastatic disease is present in tumor draining LN.

Multidisciplinary Care of BRAF-Mutant Stage III Melanoma: A Physicians Perspective Review

Prognosis among patients with stage III melanoma can vary widely depending on the risk of disease relapse. Therefore, it is vital to optimize patient care through accurate diagnosis and staging as well as thoughtful treatment planning. A multidisciplinary team (MDT) approach, which involves active collaboration among physician specialists across a patient's disease journey, has been increasingly adopted as the standard of care for treatment of a variety of cancers, including melanoma. This review provides an overview of MDT care principles for patients with BRAF‐mutant–positive, stage III cutaneous melanoma and summarizes current literature, clinical experiences, and institutional best practices. Therapeutic goals from dermatologic, surgical, and medical oncologist perspectives regarding MDT care throughout a patient's disease course are discussed. Additionally, the role of each specialty's involvement in testing for predictive biomarkers at relevant time points to facilitate informed treatment decisions is discussed. Last, instances of successful MDT treatment of other cancers and key lessons to optimize MDT patient care in cutaneous melanoma are provided. Several aspects of MDT patient care are considered vital, such as the importance of staging via pathological examination and imaging, biomarker testing, and interdisciplinary physician and patient engagement throughout the course of treatment. Use of MDTs has the potential to improve patient care in cutaneous melanoma by improving the speed and accuracy of diagnosis, implementing a personalized treatment plan early on, and being proactive in adverse event management. Physician perspectives described in this review may lead to better outcomes, quality of life, and overall patient satisfaction.

A multidisciplinary team (MDT) approach has been increasingly adopted as the standard of care for treatment of a variety of cancers, including melanoma. This review provides an overview of MDT care principles for patients with BRAF‐mutant–positive, stage III cutaneous melanoma and summarizes current literature, clinical experiences, and institutional best practices.

Lymph node dissections in cutaneous malignancy: Where are we now? A review of 10 years' experience at a tertiary centre

The surgical management of cutaneous malignancies has evolved over recent years with the introduction of novel medical therapies and an increasing emphasis upon early adjuvant systemic therapy. As such, completion lymph node dissection (cLND) is now no longer recommended following a positive sentinel lymph node biopsy (SLNB) in melanoma. We evaluated our ten-year practice at a regional tertiary centre, assessing the change in lymph node dissection (LND) caseload volume, anatomical distribution, and indication for the procedure. A retrospective search was carried out of all LNDs performed by the Plastic Surgery department at Cambridge University Hospitals NHS Trust, UK from 1 January 2010 to 31 December 2019. Case notes were retrospectively analysed for each procedure, with the site and pathology recorded. A total of 491 LNDs were performed over the 10-year period. Surgical volume peaked in 2015 with 67 cases, followed by a decline to 41 cases in 2019. The number of neck dissections increased over the decade, as well as the proportion of cases due to macroscopic nodal disease. We sub-analysed the number of LNDs in three contiguous 18-month intervals, corresponding to changes in practice due to evidence from the DeCOG and MSLT-II Trials. We found a 41.67% reduction in LNDs caseload between July 2018-Dec 2019, compared to a similar period prior to trial evidence (July 2015-Dec 2016) (p=0.0.14). In summary, the surgical volume of LNDs has decreased significantly since 2018, reflecting emerging evidence and changes to national guidelines. This will require ongoing monitoring for workforce planning and surgical training.

Lymphedema secondary to melanoma treatments: diagnosis, evaluation, and treatments

Approximately 300,000 new cases of melanoma are annually diagnosed in the world. Advanced stage melanomas require sentinel lymph node biopsy (SLNB), sometimes lymph node dissections (LND). The development rate of lower extremity lymphedema ranges from 7.6% to 35.1% after inguinal SLNB, and from 48.8% to 82.5% after inguinal LND. Development rate of upper extremity lymphedema ranges from 4.4% to 14.6% after axillary LND. Lymphedema management has constantly improved but effective evaluation and surgical management such as supermicrosurgical lymphaticovenular anastomosis (LVA) are becoming common as minimally invasive lymphatic surgery. Diagnosis and new classification using indocyanine green lymphography allowing pre-clinical secondary lymphedema stage management are improving effectiveness of supermicrosurgical LVA and vascularized lymph node transfer. Lymphatic transfer with lymph-interpositional-flap can restore lymph flow after large oncologic excision even without performing lymphatic anastomosis. Since lymphatic reconstructive surgery may affect local to systemic dissemination of remnant tumor cells, careful consideration is required to evaluate indication of surgical treatments.

Sentinel node tumor burden in prediction of prognosis in melanoma patients

Recent data have demonstrated no survival benefit to immediate completion lymph node dissection (CLND) for positive sentinel node (SN) disease in melanoma. It is important to identify parameters in positive SNs, which predict prognosis in melanoma patients. These might provide prognostic value in staging systems and risk models by guiding high-risk patients’ adjuvant therapy in clinical practice. In this retrospective study of university hospital melanoma database we analyzed tumor burden and prognosis in patients with positive SNs. Patients were stratified by the diameter of tumor deposit, distribution of metastatic focus in SN, ulceration and number of metastatic SNs. These were incorporated in Cox proportional hazard regression models. Predictive ability was assessed using Akaike information criterion and Harrell’s concordance index. A total of 110 patients had positive SN and 104 underwent CLND. Twenty-two (21%) patients had non-SN metastatic disease on CLND. The 5-year melanoma specific survival for CLND-negative patients was 5.00 years (IQR 3.23–5.00, range 0.72–5.00) compared to 3.69 (IQR 2.28–4.72, range 1.01–5.00) years in CLND-positive patients (HR 2.82 (95% CI 1.17–6.76, p = 0.020).The models incorporating distribution of metastatic focus and the largest tumor deposit in SN had highest predictive ability. According to Cox proportional hazard regression models, information criterions and c-index, the diameter of tumor deposit > 4 mm with multifocal location in SN despite of number of metastatic SN were the most important parameters. According to the diameter of tumor deposit and distribution of metastatic focus in SN, adequate stratification of positive SN patients was possible and risk classes for patients were identified.

Does the time interval between sentinel lymph node biopsy and completion lymph node dissection affect outcome in malignant melanoma? A retrospective cohort study

Nodal clearance was recommended after positive sentinel lymph node biopsy (SLNB) despite further metastases to the regional lymph node basin being found in only 6-21% in the literature. This retrospective study was conducted to determine the role of the time interval between excision of primary melanoma and confirmed metastasis in the sentinel lymph node biopsy as well as the one between positive sentinel lymph node biopsy (SLNB-positive patients) and subsequent completion lymph node dissection (CLND) on the presence of metastases. The monocentric analysis included 121 patients with a history of completion lymph node dissection after positive SLNB from January 2005 to October 2013. Additional metastases in the regional lymph node basin (non-sentinels) were found in 14.05% (n = 17). Significant risk factors for the presence of metastases in CLND were the time between confirmed primary tumour to metastasis in sentinel lymph nodes (SLN) (p = 0.0034), N-category of TNM-classification (p = 0.0066) and independent of thickness of primary tumour (p = 0.11). If SLNB was performed up to forty-three days after confirmed primary melanoma, subsequent lymph node dissection was positive in less than 9.1%. When SLNB was performed with a delay of more than 80 days, all patients had metastases in the CLND specimens. Our data analysis suggests that delays in subsequent procedures of SLNB after diagnosis of primary melanoma may have a greater impact on positivity of non-sentinel lymph nodes than previously assumed. Our retrospective analysis may indicate the reconsideration of time schedule in the management of primary melanoma to potentially avoid local relapse in the draining lymph node region after positive SLNB.

Nonsurgical Management of Lymph Node Basins in Melanoma

In this article we provide a critical review of the evidence available for surgical management of the nodal basin in melanoma, with an aim to ensure an understanding of risks and benefits for all lymph node surgery offered to patients, and alternatives to surgical management where appropriate.

An evidence-based approach to positive sentinel node disease: should we ever do a completion node dissection?

Management of later stage melanoma has undergone significant changes. Sentinel node biopsy has long been an accepted method of staging, but two recent randomized-controlled trials have provided an evidence base for decision making about completion lymphadenectomy. They showed no survival advantage in further surgery for patients with positive sentinel node biopsies. There is now no evidence to support completion lymphadenectomy in the majority of patients, and this is reflected in international practice guidelines.

Immunologic and immunogenomic aspects of tumor progression

Tumor progression to metastatic disease is characterized by continuous genetic alterations due to instability of the genome. Immune sensitivity was found to be linked to tumor mutational burden (TMB) and the resulting amount of neoantigens. However, APOBEC activity resulting in increase in TMB causes immune evasion. On the other hand, clonal or acquired genetic loss of HLA class I also hampers immune sensitivity of tumors. Rare amplification of the PD-L1 gene in cancers may render them sensitive to immune checkpoint inhibitors but involvement of broader regions of chromosome 9p may ultimately lead again to immune evasion due to inactivation of the IFN-γ signaling pathway. Such genetic changes may occur not only in the primary tumor but at any phase of progression: in lymphatic as well as in visceral metastases. Accordingly, it is rational to monitor these changes continuously during disease progression similar to target therapies. Moreover, beside temporal variability, genomic features of tumors such as mutation profiles, as well as the tumor immune microenvironment also show considerable inter- and intratumoral spatial heterogeneity, suggesting the necessity of multiple sampling in biomarker studies.

Validation of Melanoma Immune Profile (MIP), a Prognostic Immune Gene Prediction Score for Stage II-III Melanoma

PURPOSE

Biomarkers are needed to stratify patients with stage II-III melanoma for clinical trials of adjuvant therapy because, while immunotherapy is protective, it also confers the risk of severe toxicity. We previously defined and validated a 53-immune gene melanoma immune profile (MIP) predictive both of distant metastatic recurrence and of disease-specific survival (DSS). Here, we test MIP on a third independent population.

EXPERIMENTAL DESIGN

A retrospective cohort of 78 patients with stage II-III primary melanoma was analyzed using the NanoString assay to measure expression of 53 target genes, and MIP score was calculated. Statistical analysis correlating MIP with DSS, overall survival, distant metastatic recurrence, and distant metastasis-free interval was performed using ROC curves, Kaplan-Meier curves, and standard univariable and multivariable Cox proportional hazards models.

RESULTS

MIP significantly distinguished patients with distant metastatic recurrence from those without distant metastatic recurrence using ROC curve analysis (AUC = 0.695; P = 0.008). We defined high- and low-risk groups based on the cutoff defined by this ROC curve and find that MIP correlates with both DSS and overall survival by ROC curve analysis (AUC = 0.719; P = 0.004 and AUC = 0.698; P = 0.004, respectively). Univariable Cox regression reveals that a high-risk MIP score correlates with DSS (P = 0.015; HR = 3.2).

CONCLUSIONS

MIP identifies patients with low risk of death from melanoma and may constitute a clinical tool to stratify patients with stage II-III melanoma for enrollment in clinical trials.