The interval between primary melanoma excision and sentinel node biopsy is not associated with survival in sentinel node positive patients – An EORTC Melanoma Group study

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

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

The Current Treatment Trends and Survival Patterns in Melanoma Patients with Positive Sentinel Lymph Node Biopsy (SLNB): A Multicenter Nationwide Study

BACKGROUND

In melanoma treatment, an approach following positive sentinel lymph node biopsy (SLNB) has been recently deescalated from completion lymph node dissection (CLND) to active surveillance based on phase III trials data. In this study, we aim to evaluate treatment strategies in SLNB-positive melanoma patients in real-world practice.

METHODS

Five-hundred-fifty-seven melanoma SLNB-positive patients from seven comprehensive cancer centers treated between 2017 and 2021 were included. Kaplan-Meier methods and the Cox Proportional-Hazards Model were used for analysis.

RESULTS

The median follow-up was 25 months. Between 2017 and 2021, the percentage of patients undergoing CLND decreased (88-41%), while the use of adjuvant treatment increased (11-51%). The 3-year OS and RFS rates were 77.9% and 59.6%, respectively. Adjuvant therapy prolonged RFS (HR:0.69, p = 0.036)), but CLND did not (HR:1.22, p = 0.272). There were no statistically significant differences in OS for either adjuvant systemic treatment or CLND. Lower progression risk was also found, and time-dependent hazard ratios estimation in patients treated with systemic adjuvant therapy was confirmed (HR:0.20, p = 0.002 for BRAF inhibitors and HR:0.50, p = 0.015 for anti-PD-1 inhibitors).

CONCLUSIONS

Treatment of SLNB-positive melanoma patients is constantly evolving, and the role of surgery is currently rather limited. Whether CLND has been performed or not, in a group of SLNB-positive patients, adjuvant systemic treatment should be offered to all eligible patients.

Association of tumor molecular factors with in-transit metastasis in primary cutaneous melanoma

BACKGROUND

In-transit metastases (ITM) are a form of locoregional relapse representing intralymphatic metastatic spread and occur in approximately 4-9% of patients with melanoma >1 mm Breslow thickness. Our objective was to evaluate a combination of clinicopathologic risk factors and gene expression biomarkers predictive of ITM risk.

METHODS

We used PCR to quantify gene expression in diagnostic biopsy tissue across a prospectively designed archival cohort of 854 consecutive thin and intermediate thickness primary cutaneous melanomas. The outcome of interest was ITM >90 days after a melanoma diagnosis. Cox proportional hazard models were fit to estimate each clinicopathologic and molecular characteristic's association with the risk of ITM.

RESULTS

The 5-year cumulative incidence of ITM was 3.2%. Clinical factors univariately associated with an increased risk of ITM were older age, greater Breslow thickness, greater mitotic rate, lower extremity location, ulceration, and a positive SLN biopsy. Of 108 genes tested, five were significantly upregulated and five significantly downregulated when evaluated in Cox models adjusted for age, Breslow thickness, mitotic rate, and lower extremity location. Among the upregulated genes, the strongest association was observed for interleukin-8 (IL8).

CONCLUSION

A subset of gene expression biomarkers was identified as independently associated with the risk of ITM after adjusting for key covariates. Once sufficiently validated, our results may lead the way to regional therapy trials for a small, selected group of high-risk patients.

Does Residual Invasive Disease in Wide Local Excision after Diagnosis with Partial Biopsy Technique Influence Survival in Melanoma? Matched-Pair Analysis of Multicenter Selective Lymphadenectomy Trial I and II

BACKGROUND

Current guidelines recommend excisional/complete biopsy for melanoma diagnosis, owing to high rates of residual disease found at wide local excision (WLE) after partial biopsy techniques. We sought to determine any survival disadvantage associated with the presence of residual invasive melanoma in the WLE after diagnosis with a partial biopsy technique.

STUDY DESIGN

Data were examined from Multicenter Selective Lymphadenectomy Trials I and II (MSLT-I and -II), 2 large melanoma trials. Patients diagnosed with excisional/complete biopsy were excluded. Clinicopathologic characteristics, melanoma-specific survival (MSS), distant disease-free survival (DDFS), and disease-free survival (DFS) of those with residual invasive melanoma in the definitive WLE and those with no residual melanoma were compared. Matched pairing was used to reduce variability between groups.

RESULTS

From 1994 through 2014, 3,939 patients were enrolled in these trials and 874 (22%) were diagnosed using partial biopsy techniques. Of these, 399 (46%) had residual tumor in the WLE. Only 6 patients had residual tumor in their WLE resulting in T-upstaging of their tumor. Match-pairing formed two cohorts (1:1) of patients with and without residual invasive tumor after WLE. A total of 514 patients were paired; 288 (56%) males, 148 (28.8%) aged 60 or older, 192 (37.4%) with truncal melanomas, 214 (41.6%) had Breslow thickness 2 mm or greater, and 376 (73.2%) had positive sentinel nodes. Kaplan-Meier analysis showed no statistical difference in 10-year MSS (73.6% ± 3.3% vs 73.9% ± 3.7%, p = 0.891), DDFS (68.7% ± 3.4% vs 65.3% ± 4.0%, p = 0.548), or DFS (59.6% ± 3.7% vs 59.4% ± 3.9%, p = 0.783).

CONCLUSIONS

Survival in patients with primary melanoma does not appear to be worse in patients who undergo a partial biopsy technique and are later found to have residual invasive tumor in the WLE specimen.

Impact of the time interval between primary melanoma excision and sentinel node biopsy: A systematic review and meta-analysis

BACKGROUND

Obtaining a sentinel lymph node biopsy (SLNB) specimen is a standard staging procedure in the management of cutaneous melanoma. However, there is no consensus on the safe time interval between the primary melanoma biopsy procedure and the SLNB procedure.

OBJECTIVE

We evaluated the association between time from biopsy to SLNB and patients' outcomes for melanoma.

METHODS

We performed this systematic review and meta-analysis based on the recommendations of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.

RESULTS

Six retrospective studies were included. Nine thousand seven hundred five patients were identified, of which 4383 underwent a SNLB procedure at a time interval defined as early and 4574 at an interval defined as late. A combined hazard ratio of 1.25 (95% confidence interval [CI] 0.92-1.68) was determined, and there was high heterogeneity (I² = 83%; P = .002) of the SLNB time interval on melanoma-specific survival. The combined HR for disease-free survival was 1.05 (95% CI 0.95-1.15), with low heterogeneity (I² = 9%; P = .36). Regarding overall survival, a combined HR of 1.25 (95% CI 0.92-1.70) was found, with low heterogeneity (I² = 37%; P = .2).

LIMITATIONS

There is heterogeneity between some studies.

CONCLUSION

There are no significant differences in patient outcome between a short interval versus a long interval between the primary biopsy procedure and obtaining a SNLB specimen.

Does very early timing of lymph node surgery after resection of the primary tumour improve the clinical outcome of patients with melanoma?

BACKGROUND

In patients with cutaneous melanoma (CM), the time span between resection of the primary tumour and sentinel lymph node biopsy (SLNB) as well as the subsequent interval between SLNB and complete lymph node dissection (CLND) varies greatly.

AIM

To determine whether very early timing of SLNB after resection of the primary tumour, or timing of CLND after SLNB affect the clinical outcome of patients with CM, compared with longer time intervals.

METHODS

We compared the time spans between complete resection of the primary tumour and SLNB, and the interval between SLNB and CLND in a cohort of 896 patients with melanoma who had undergone SLNB. An interval between primary resection and SLNB or between SLNB and CLND of up to 7 days was classified as very early (VE-SLNB and VE-CLND, respectively). This time span was compared with intervals of > 7 days. Univariate and multivariate statistics were performed.

RESULTS

VE-SLNB was significantly associated with the presence of micrometastases. However, this was probably due to tumour thickness being significantly higher in patients with VE-SLNB compared with patients with later SLNB. Importantly, VE-SLNB was not significantly associated with disease relapse and VE-CLND was not associated with melanoma-specific death.

CONCLUSIONS

VE-SLNB and VE-CLND neither improved nor worsened the clinical outcome of patients. Thus, timing of SLNB and CLND has no influence on the overall clinical outcome of patients with melanoma. Our findings support the rational planning of lymph node surgery after resection of the primary tumour and provide help for effective patient counselling.

Identification of stage I/IIA melanoma patients at high risk for disease relapse using a clinicopathologic and gene expression model

PURPOSE

Patients with stage I/IIA cutaneous melanoma (CM) are currently not eligible for adjuvant therapies despite uncertainty in relapse risk. Here, we studied the ability of a recently developed model which combines clinicopathologic and gene expression variables (CP-GEP) to identify stage I/IIA melanoma patients who have a high risk for disease relapse.

PATIENTS AND METHODS

Archival specimens from a cohort of 837 consecutive primary CMs were used for assessing the prognostic performance of CP-GEP. The CP-GEP model combines Breslow thickness and patient age, with the expression of eight genes in the primary tumour. Our specific patient group, represented by 580 stage I/IIA patients, was stratified based on their risk of relapse: CP-GEP High Risk and CP-GEP Low Risk. The main clinical end-point of this study was five-year relapse-free survival (RFS).

RESULTS

Within the stage I/IIA melanoma group, CP-GEP identified a high-risk patient group (47% of total stage I/IIA patients) which had a considerably worse five-year RFS than the low-risk patient group; 74% (95% confidence interval [CI]: 67%-80%) versus 89% (95% CI: 84%-93%); hazard ratio [HR] = 2.98 (95% CI: 1.78-4.98); P < 0.0001. Of patients in the high-risk group, those who relapsed were most likely to do so within the first 3 years.

CONCLUSION

The CP-GEP model can be used to identify stage I/IIA patients who have a high risk for disease relapse. These patients may benefit from adjuvant therapy.

β3 integrin immunohistochemistry as a method to predict sentinel lymph node status in patients with primary cutaneous melanoma

BACKGROUND

Integrins are heterodimeric proteins composed of noncovalently linked ɑ and β subunits which are essential for a wide range of normal physiology and also play prominent roles in cancer. Here we tested whether integrin expression in diagnostic skin biopsies is associated with sentinel lymph node (SLN) metastasis.

METHODS

We utilized a cohort of 854 consecutive patients with primary cutaneous melanoma to quantify the expression of β integrin subunits by reverse transcriptase quantitative PCR (RT-qPCR). In addition, we quantified the expression of β3 integrin by immunohistochemistry (IHC) in a subset of 271 patients by H score. Outcome of interest was SLN biopsy metastasis within 90 days of melanoma diagnosis. Logistic regression analyses were used to develop models for the likelihood of SLN metastasis from molecular, clinical, and histologic variables.

RESULTS

β3 integrin expression quantified by IHC or RT-qPCR was associated with SLN metastasis. β1, β5, β6, and β8 integrin expression was not associated with SLN metastasis. The incremental gain in performance of a predictive model which included β3 integrin expression as quantified by IHC in combination with established clinicopathologic variables (Breslow depth and patient age) was limited.

CONCLUSIONS

β3 integrin is the principal integrin subunit associated with sentinel lymph node biopsy (SLNb) metastasis in primary cutaneous melanoma. However, β3 integrin H score does not significantly improve models for the likelihood of SLN metastasis over Breslow depth and patient age.

Timing of sentinel node biopsy independently predicts disease-free and overall survival in clinical stage I-II melanoma patients: A multicentre study of the Italian Melanoma Intergroup (IMI)

Background

Sentinel lymph node biopsy (SNB) still remains a key procedure to appropriately stage melanoma patients and to select those who are candidate to novel treatments with immunotherapy and targeted therapy in the adjuvant setting. The impact of timing of SNB on disease-free survival (DFS) and overall survival (OS) is still unclear.

Material and methods

The study was conducted at 6 Italian Melanoma Intergroup (IMI) centres and included 8953 consecutive clinical stage I-II melanoma patients who were diagnosed, treated, and followed up between November 1997 and March 2018. All patients were prospectively included in dedicated IMI database. Multivariable Cox regression analyses were performed to investigate how baseline characteristics and time interval until SNB are related to DFS and OS.

Results

Considering the whole population, at multivariable analysis, after adjusting for age, gender, Breslow thickness, site, ulceration, and the SNB status, a delay in the timing of SNB was associated with a better DFS (adjusted hazard ratio [aHR, delayed versus early SNB] 0.98, 95% confidence interval [CI] 0.97–0.99, p < 0.001) and OS (aHR 0.98, 95% CI 0.97–0.99, p = 0.001). Specifically, in patients with a negative SNB status, a beneficial impact of delayed SNB (i.e. at least 32 days after primary excision) was confirmed for DFS (aHR 0.70, 95%CI 0.63–0.79, p < 0.001) and OS (aHR 0.69, 95%CI 0.61–0.78, p < 0.001), whereas in those with a positive SNB status, DFS (aHR 0.96, 95%CI 0.84–1.09, p = 0.534) and OS (aHR 0.94 95%CI 0.81–1.08, p = 0.374) were not significantly different in patients with early or delayed SNB.

Conclusions

Our study does not support a strict time interval for SNB. These results may be useful for national guidelines, for counselling patients and reducing the number of high urgency referrals.

The EORTC-DeCOG nomogram adequately predicts outcomes of patients with sentinel node-positive melanoma without the need for completion lymph node dissection

PURPOSE

Based on recent advances in the management of patients with sentinel node (SN)-positive melanoma, we aimed to develop prediction models for recurrence, distant metastasis (DM) and overall mortality (OM).

METHODS

The derivation cohort consisted of 1080 patients with SN-positive melanoma from nine European Organization for Research and Treatment of Cancer (EORTC) centres. Prognostic factors for recurrence, DM and OM were studied with Cox regression analysis. Significant factors were incorporated in the models. Performance was assessed by discrimination (c-index) and calibration in cross-validation across centres. The models were externally validated using a prospective cohort consisting of 705 German patients with SN-positive: 473 trial participants of the German Dermatologic Cooperative Oncology Group study (DeCOG-SLT) and 232 screened patients. A nomogram was developed for graphical presentation.

RESULTS

The final model for recurrence and the calibrated models for DM and OM included ulceration, age, SN tumour burden and Breslow thickness. The models showed reasonable calibration. The c-index for the recurrence, DM and OM model was 0.68, 0.70 and 0.70, respectively, and 0.70, 0.72 and 0.74, respectively, in external validation. The EORTC-DeCOG model identified a robust low-risk group, with all identified low-risk patients (approximately 4% of the entire population) having a 5-year recurrence probability of <25% and an overall 5-year recurrence rate of 13%. A model including information on completion lymph node dissection (CLND) showed only marginal improvement in model performance.

CONCLUSIONS

The EORTC-DeCOG nomogram provides an adequate prognostic tool for patients with SN-positive melanoma, without the need for CLND. It showed consistent results across validation. The nomogram could be used for patient counselling and might aid in adjuvant therapy decision-making.

Model Combining Tumor Molecular and Clinicopathologic Risk Factors Predicts Sentinel Lymph Node Metastasis in Primary Cutaneous Melanoma

PURPOSE

More than 80% of patients who undergo sentinel lymph node (SLN) biopsy have no nodal metastasis. Here we describe a model that combines clinicopathologic and molecular variables to identify patients with thin and intermediate thickness melanomas who may forgo the SLN biopsy procedure due to their low risk of nodal metastasis.

PATIENTS AND METHODS

Genes with functional roles in melanoma metastasis were discovered by analysis of next generation sequencing data and case control studies. We then used PCR to quantify gene expression in diagnostic biopsy tissue across a prospectively designed archival cohort of 754 consecutive thin and intermediate thickness primary cutaneous melanomas. Outcome of interest was SLN biopsy metastasis within 90 days of melanoma diagnosis. A penalized maximum likelihood estimation algorithm was used to train logistic regression models in a repeated cross validation scheme to predict the presence of SLN metastasis from molecular, clinical and histologic variables.

RESULTS

Expression of genes with roles in epithelial-to-mesenchymal transition (glia derived nexin, growth differentiation factor 15, integrin β3, interleukin 8, lysyl oxidase homolog 4, TGFβ receptor type 1 and tissue-type plasminogen activator) and melanosome function (melanoma antigen recognized by T cells 1) were associated with SLN metastasis. The predictive ability of a model that only considered clinicopathologic or gene expression variables was outperformed by a model which included molecular variables in combination with the clinicopathologic predictors Breslow thickness and patient age; AUC, 0.82; 95% CI, 0.78-0.86; SLN biopsy reduction rate of 42% at a negative predictive value of 96%.

CONCLUSION

A combined model including clinicopathologic and gene expression variables improved the identification of melanoma patients who may forgo the SLN biopsy procedure due to their low risk of nodal metastasis.

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.

ECCO essential requirements for quality cancer care: Melanoma

BACKGROUND

ECCO essential requirements for quality cancer care (ERQCC) are explanations and descriptions of challenges, organisation and actions that are necessary to give high-quality care to patients who have a specific type of cancer. They are written by European experts representing all disciplines involved in cancer care. ERQCC papers give oncology teams, patients, policymakers and managers an overview of the elements needed in any healthcare system to provide high quality of care throughout the patient journey. References are made to clinical guidelines and other resources where appropriate, and the focus is on care in Europe.

MELANOMA

ESSENTIAL REQUIREMENTS FOR QUALITY CARE: CONCLUSION: Taken together, the information presented in this paper provides a comprehensive description of the essential requirements for establishing a high-quality service for melanoma. The ERQCC expert group is aware that it is not possible to propose a 'one size fits all' system for all countries, but urges that access to multidisciplinary teams and specialised treatments is guaranteed to all patients with melanoma.

Impact of Time Between Diagnosis and SLNB on Outcomes in Cutaneous Melanoma

BACKGROUND

Hypothetically, delay between melanoma diagnosis and SLNB could affect outcomes, either adversely by allowing growth and dissemination of metastases, or beneficially by allowing development of an anti-melanoma immune response. Available data are conflicting about the effect of SLNB delay on patient survival. Our objective was to determine whether delay between initial diagnosis and SLNB affects outcomes in patients with cutaneous melanoma.

STUDY DESIGN

We performed query and analysis of a large prospectively maintained database of patients with primary cutaneous melanomas undergoing SLNB. An independent dataset from MSLT-1 (Multicenter Selective Lymphadenectomy Trial-1) was used for validation. Primary outcomes included disease-free survival and melanoma-specific survival.

RESULTS

Early and delayed SLNB were defined as less than 30 and 30 or more days from initial diagnosis, respectively. There were 2,483 patients that met inclusion criteria. Positive sentinel lymph nodes were identified in 17.4% (n = 432). Among all patients, 42% had SLNB 30 or more days after diagnosis and 37% of positive sentinel lymph nodes were at 30 or more days. No differences in sex, anatomic site, or histopathologic features were identified between the 2 groups. There was no difference in melanoma-specific survival or disease-free survival between those undergoing early or delayed SLNB. Examination of MSLT-1 trial data similarly demonstrated no difference in survival outcomes.

CONCLUSIONS

This, the largest study on this subject to date, found no adverse impact on long-term clinical outcomes of patients due to delay of SLNB beyond 30 days. The MSLT-1 data confirm this result. Patients can be reassured that if the operation is performed 30 or more days after diagnosis, it will not cause harm.

Timing of completion lymphadenectomy after positive sentinel node biopsy in patients with melanoma

Background

Nodal staging with sentinel node biopsy (SNB) and completion lymph node dissection (CLND) provides prognostic information to patients with melanoma and their physicians. It is not known whether the timing of CLND is associated with survival outcome and/or CLND tumour load. This study investigated whether CLND timing is associated with CLND tumour load, disease-free survival (DFS) and/or melanoma-specific survival (MSS).

Methods

A retrospective cohort of patients with SNB-positive melanoma from nine European Organisation for Research and Treatment of Cancer (EORTC) Melanoma Group centres undergoing surgery between 1993 and 2009 were examined. Patients were selected based on availability of CLND and follow-up data. The CLND interval was defined as the number of days between diagnosis and CLND. Patient and tumour characteristics were collected. Five-year DFS and MSS rates were calculated. Cox and logistic regression analysis were performed, adjusting for known prognostic/predictive indicators.

Results

A total of 784 patients were included in the study. Their median age was 51 (i.q.r. 40–62) years, and 418 patients (53·3 per cent) were men. Median Breslow thickness was 3·0 (i.q.r. 2·0–5·0) mm, and 148 patients (18·9 per cent) had a residual tumour load. Median CLND interval was 84 (i.q.r. 65–105) days. Five-year DFS and MSS rates were not significantly different for patients operated on with a median CLND interval of less than 84 days and those with an interval of at least 84 days (DFS: 54·2 versus 53·3 per cent respectively; MSS: 66·9 versus 65·1 per cent). In a multivariable Cox model, CLND interval was not a significant prognostic indicator. CLND interval was negatively correlated with identification of positive non-sentinel nodes, but following adjustment for known risk factors this effect was no longer found.

Conclusion

The time interval between diagnosis of melanoma and CLND did not influence CLND tumour load, DFS or MSS.