Five-year analysis of neoadjuvant dabrafenib and trametinib for stage III melanoma.

BACKGROUND: Neoadjuvant dabrafenib plus trametinib has a high pathological response rate and impressive short-term survival in patients with resectable stage III melanoma. We report five-year outcomes from the phase II NeoCombi trial. METHODS: NeoCombi (NCT01972347) was a single-arm, open-label, single-centre, phase II trial. Eligible patients were adults (aged ≥18) with histologically-confirmed, resectable, RECIST-measurable AJCC 7th ed. clinical stage IIIB-C BRAF V600E/K-mutant melanoma and Eastern Co-operative Oncology Group performance status ≤1. Patients received 52 weeks of treatment with 150 mg dabrafenib (orally twice per day) plus 2 mg trametinib (orally once per day), with complete resection of the pre-therapy tumour bed at Week 12. RESULTS: Between August 20, 2014, and April 19, 2017, 35 patients were enrolled. At data cut-off (August 17, 2021), the median follow-up was 60 months (95% CI 56-72). Overall, 21 of 35 (60%) patients recurred, including twelve (57%) with first recurrence in locoregional sites (followed by later distant recurrence in six) and nine (43%) with first recurrence in distant sites, including three in the brain. Most recurrences occurred within two years, with no recurrences beyond three years. At five years, recurrence-free survival was 40% (95% CI 27-60), distant metastasis-free survival was 57% [95% CI 42-76%], and overall survival was 80% (95% CI 67-94). Five-year survival outcomes were stratified by pathological response: recurrence-free survival was 53% with pCR versus 28% with non-pCR (p=0.087), distant metastasis-free survival was 59% versus 55% (p=0.647), and overall survival was 88% versus 71% (p=0.205), respectively. CONCLUSIONS: Neoadjuvant dabrafenib plus trametinib has high pathological response rates in clinical stage III melanoma, but low rates of recurrence-free survival, similar to those achieved with adjuvant targeted therapy alone. Patients with a pCR to dabrafenib plus trametinib still had a high risk of recurrence, unlike that seen with immunotherapy where recurrences are rare.

The Effect of Neoadjuvant Systemic Therapy on Surgical Outcomes After Lymph Node Dissections for Stage III Melanoma; An Australian Cohort.

BACKGROUND: Neoadjuvant systemic therapy (NAST) for patients with stage III melanoma achieves high major pathologic response rates and high recurrence-free survival rates. This study aimed to determine how NAST with targeted therapies (TTs) and immune checkpoint inhibitors (ICIs) influences surgical outcomes after lymph node dissection in terms of complications, morbidity, and textbook outcomes. METHODS: Patients who underwent a lymph node dissection after either NAST in a clinical trial or upfront surgery for stage III melanoma between 2014 and 2022 were identified from an institutional research database. RESULTS: The study included 89 NAST-treated patients and 79 upfront surgery-treated patients. The rate of postoperative complications did not differ between the NAST- and upfront surgery-treated patients (55% vs. 51%; p = 0.643), and steroid treatment for drug toxicity did not influence the complication rate (odds ratio [OR], 1.1; 95% confidence interval [CI], 0.4-3; p = 0.826). No significant differences in postoperative morbidity were observed in terms of seroma (23% vs. 11%; p = 0.570) or lymphedema (36% vs. 51%; p = 0.550). The rate of achieving a textbook outcome was comparable for the two groups (61% vs. 57%; p = 0.641). CONCLUSIONS: The surgical outcomes after lymph node dissections were comparable between the patients who received NAST and those who had upfront surgery, indicating that surgery can be safely performed after NAST with TT or ICI for stage III melanoma.

Impact of an Online Risk Calculator for Sentinel Node Positivity on Management of Patients with T1 and T2 Melanomas.

BACKGROUND: Predicting which patients with American Joint Committee on Cancer (AJCC) T1-T2 melanomas will have a positive sentinel lymph node (SLN) is challenging. Melanoma Institute Australia (MIA) developed an internationally validated SLN metastatic risk calculator. This study evaluated the nomogram's impact on T1-T2 melanoma patient management at MIA. METHODS: SLN biopsy (SLNB) rates were compared for the pre- and post-nomogram periods of 1 July 2018-30 June 2019 and 1 August 2020-31 July 2021, respectively. RESULTS: Overall, 850 patients were identified (pre-nomogram, 383; post-nomogram, 467). SLNB was performed in 29.0% of patients in the pre-nomogram group and 34.5% in the post-nomogram group (p = 0.091). The overall positivity rate was 16.2% in the pre-nomogram group and 14.9% in the post-nomogram group (p = 0.223). SLNB was performed less frequently in T1a melanoma patients in the pre-nomogram group (1.1%, n = 2/177) than in the post-nomogram group (8.6%, n = 17/198) [p ≤ 0.001]. This increase was particularly for melanomas with a risk score ≥ 5%, with an SLN positivity rate of 11.8% in the post-nomogram group (p = 0.004) compared with zero. For T1b melanomas with a risk score of > 10%, the SLNB rate was 40.0% (8/20) pre-nomogram and 75.0% (12/16) post-nomogram (p = 0.049). CONCLUSIONS: In this specialized center, the SLN risk calculator appears to influence practice for melanomas previously considered low risk for metastasis, with increased use of SLNB for T1a and higher-risk T1b melanomas. Further evaluation is required across broader practice settings. Melanoma management guidelines could be updated to incorporate the availability of nomograms to better select patients for SLNB than previous criteria.

Development and validation of a novel model to predict recurrence-free survival and melanoma-specific survival after sentinel lymph node biopsy in patients with melanoma: an international, retrospective, multicentre analysis.

BACKGROUND: The introduction of adjuvant systemic treatment for patients with high-risk melanomas necessitates accurate staging of disease. However, inconsistencies in outcomes exist between disease stages as defined by the American Joint Committee on Cancer (8th edition). We aimed to develop a tool to predict patient-specific outcomes in people with melanoma rather than grouping patients according to disease stage. METHODS: Patients older than 13 years with confirmed primary melanoma who underwent sentinel lymph node biopsy (SLNB) between Oct 29, 1997, and Nov 11, 2013, at four European melanoma centres (based in Berlin, Germany; Amsterdam and Rotterdam, the Netherlands; and Warsaw, Poland) were included in the development cohort. Potential predictors of recurrence-free and melanoma-specific survival assessed were sex, age, presence of ulceration, primary tumour location, histological subtype, Breslow thickness, sentinel node status, number of sentinel nodes removed, maximum diameter of the largest sentinel node metastasis, and Dewar classification. A prognostic model and nomogram were developed to predict 5-year recurrence-free survival on a continuous scale in patients with stage pT1b or higher melanomas. This model was also calibrated to predict melanoma-specific survival. Model performance was assessed by discrimination (area under the time-dependent receiver operating characteristics curve [AUC]) and calibration. External validation was done in a cohort of patients with primary melanomas who underwent SLNB between Jan 30, 1997, and Dec 12, 2013, at the Melanoma Institute Australia (Sydney, NSW, Australia). FINDINGS: The development cohort consisted of 4071 patients, of whom 2075 (51%) were female and 1996 (49%) were male. 889 (22%) had sentinel node-positive disease and 3182 (78%) had sentinel node-negative disease. The validation cohort comprised 4822 patients, of whom 1965 (41%) were female and 2857 (59%) were male. 891 (18%) had sentinel node-positive disease and 3931 (82%) had sentinel node-negative disease. Median follow-up was 4·8 years (IQR 2·3-7·8) in the development cohort and 5·0 years (2·2-8·9) in the validation cohort. In the development cohort, 5-year recurrence-free survival was 73·5% (95% CI 72·0-75·1) and 5-year melanoma-specific survival was 86·5% (85·3-87·8). In the validation cohort, the corresponding estimates were 66·1% (64·6-67·7) and 83·3% (82·0-84·6), respectively. The final model contained six prognostic factors: sentinel node status, Breslow thickness, presence of ulceration, age at SLNB, primary tumour location, and maximum diameter of the largest sentinel node metastasis. In the development cohort, for the model's prediction of recurrence-free survival, the AUC was 0·80 (95% CI 0·78-0·81); for prediction of melanoma-specific survival, the AUC was 0·81 (0·79-0·84). External validation showed good calibration for both outcomes, with AUCs of 0·73 (0·71-0·75) and 0·76 (0·74-0·78), respectively. INTERPRETATION: Our prediction model and nomogram accurately predicted patient-specific risk probabilities for 5-year recurrence-free and melanoma-specific survival. These tools could have important implications for clinical decision making when considering adjuvant treatments in patients with high-risk melanomas. FUNDING: Erasmus Medical Centre Cancer Institute.

Predicting Recurrence-Free and Overall Survival for Patients With Stage II Melanoma: The MIA Calculator.

PURPOSE: Improvements in recurrence-free survival (RFS) were demonstrated in two recent randomized trials for patients with sentinel node (SN)-negative stage IIB or IIC melanoma receiving adjuvant systemic therapy (pembrolizumab/nivolumab). However, adverse events also occurred. Accurate individualized prognostic estimates of RFS and overall survival (OS) would allow patients to more accurately weigh the risks and benefits of adjuvant therapy. Since the current American Joint Committee on Cancer eighth edition (AJCC-8) melanoma staging system focuses on melanoma-specific survival, we developed a multivariable risk prediction calculator that provides estimates of 5- and 10-year RFS and OS for these patients. METHODS: Data were extracted from the Melanoma Institute Australia (MIA) database for patients diagnosed with stage II (clinical or pathological) melanoma (n = 3,220). Survival prediction models were developed using multivariable Cox regression analyses (MIA models) and externally validated twice using data sets from the United States and the Netherlands. Each model's performance was assessed using C-statistics and calibration plots and compared with Cox models on the basis of AJCC-8 staging (stage models). RESULTS: The 5-year and 10-year RFS C-statistics were 0.70 and 0.73 (MIA-model) versus 0.61 and 0.60 (stage-model), respectively. For OS, the 5-year and 10-year C-statistics were 0.71 and 0.75 (MIA-model) compared with 0.62 and 0.61 (stage-model), respectively. The MIA models were well calibrated and externally validated. CONCLUSION: The MIA models offer accurate and personalized estimates of both RFS and OS in patients with stage II melanoma even in the absence of pathological staging with SN biopsy. These models were robust on external validations and may be used in everyday practice both with (ideally) and without performing SN biopsy to identify high-risk patients for further management strategies. An online tool will be available at the MIA website (Risk Prediction Tools).

Transmission and Non-transmission of Melanoma From Deceased Solid Organ Donors to Transplant Recipients: Risks and Missed Opportunities.

BACKGROUND: Biovigilance concerns are in tension with the need to increase organ donation. Cancer transmission risk from donor to recipient may be overestimated, as non-transmission events are rarely reported. We sought to estimate melanoma transmission risk in deceased organ donation and identify missed opportunities for donation in an Australian cohort with high melanoma prevalence. METHODS: We used a population-based approach and linked deceased organ donors, transplant recipients, and potential donors forgone, 2010-2018, with the Central Cancer Registry (CCR), 1976-2018. We identified melanomas using ICD-O-3 classification, assessed the probability of transmission, and compared suspected melanoma history in potential donors forgone with melanoma notifications in the CCR. RESULTS: There were 9 of 993 donors with melanoma in CCR; 4 in situ low-risk and 5 invasive high-to-unacceptable risk. Four were unrecognized before donation. Of 16 transplant recipients at risk, we found 0 of 14 transmission events (2 recipients had insufficient follow-up). Of 35 of 3588 potential donors forgone for melanoma risk alone, 17 were otherwise suitable for donation; 6 of 35 had no melanoma in CCR, 2 of 35 had in situ melanomas and 9 of 35 had thin invasive melanomas (localized, ≤0.8 mm thickness). CONCLUSIONS: Our findings contribute to current evidence that suggests donors with melanomas of low metastatic potential may provide an opportunity to safely increase organ donation and so access to transplantation.

Smoking Status and Survival in Patients With Early-Stage Primary Cutaneous Melanoma.

Importance: While smoking is associated with a decreased incidence of cutaneous melanoma, the association of smoking with melanoma progression and death is not well defined. Objective: To determine the association of smoking with survival in patients with early-stage primary cutaneous melanoma. Design, Setting, and Participants: This cohort study performed a post hoc analysis of data derived from the randomized, multinational first and second Multicenter Selective Lymphadenectomy Trials (MSLT-I and MSLT-II). Participants were accrued for MSLT-I from January 20, 1994, to March 29, 2002; MSLT-II, from December 21, 2004, to March 31, 2014. Median follow-up was 110.0 (IQR, 53.4-120.0) months for MSLT-I and 67.6 (IQR, 25.8-110.2) months for MSLT-II. Patients aged 18 to 75 years with clinical stages I or II melanoma with a Breslow thickness of 1.00 mm or greater or Clark level IV to V and available standard prognostic and smoking data were included. Analyses were performed from October 4, 2022, to March 31, 2023. Exposure: Current, former, and never smoking. Main Outcomes and Measures: Melanoma-specific survival of patients with current, former, and never smoking status was assessed for the entire cohort and for nodal observation and among subgroups with sentinel lymph node biopsy (SLNB)-negative and SLNB-positive findings. Results: Of 6279 included patients, 3635 (57.9%) were men, and mean (SD) age was 52.7 (13.4) years. The most common tumor location was an extremity (2743 [43.7%]), and mean (SD) Breslow thickness was 2.44 (2.06) mm. Smoking status included 1077 (17.2%) current, 1694 (27.0%) former, and 3508 (55.9%) never. Median follow-up was 78.4 (IQR, 30.5-119.6) months. Current smoking was associated with male sex, younger age, trunk site, thicker tumors, tumor ulceration, and SLNB positivity. Current smoking was associated with a greater risk of melanoma-associated death by multivariable analysis for the entire study (hazard ratio [HR], 1.48 [95% CI, 1.26-1.75]; P < .001). Former smoking was not. The increased risk of melanoma-specific mortality associated with current smoking was greatest for patients with SLNB-negative melanoma (HR, 1.85 [95% CI, 1.35-2.52]; P < .001), but also present for patients with SLNB-positive melanoma (HR, 1.29 [95% CI, 1.04-1.59]; P = .02) and nodal observation (HR, 1.68 [95% CI, 1.09-2.61]; P = .02). Smoking at least 20 cigarettes/d doubled the risk of death due to melanoma for patients with SLNB-negative disease (HR, 2.06 [95% CI, 1.36-3.13]; P < .001). Conclusions and Relevance: The findings of this cohort study suggest that patients with clinical stage I and II melanoma who smoked had a significantly increased risk of death due to melanoma. Smoking status should be assessed at time of melanoma diagnosis and may be considered a risk factor for disease progression.

Population-Based Validation of the MIA and MSKCC Tools for Predicting Sentinel Lymph Node Status.

Importance: Patients with melanoma are selected for sentinel lymph node biopsy (SLNB) based on their risk of a positive SLN. To improve selection, the Memorial Sloan Kettering Cancer Center (MSKCC) and Melanoma Institute Australia (MIA) developed predictive models, but the utility of these models remains to be tested. Objective: To determine the clinical utility of the MIA and MSKCC models. Design, Setting, and Participants: This was a population-based comparative effectiveness research study including 10 089 consecutive patients with cutaneous melanoma undergoing SLNB from the Swedish Melanoma Registry from January 2007 to December 2021. Data were analyzed from May to August 2023. Main Outcomes and Measures,: The predicted probability of SLN positivity was calculated using the MSKCC model and a limited MIA model (using mitotic rate as absent/present instead of count/mm2 and excluding the optional variable lymphovascular invasion) for each patient. The operating characteristics of the models were assessed and compared. The clinical utility of each model was assessed using decision curve analysis and compared with a strategy of performing SLNB on all patients. Results: Among 10 089 included patients, the median (IQR) age was 64.0 (52.0-73.0) years, and 5340 (52.9%) were male. The median Breslow thickness was 1.8 mm, and 1802 patients (17.9%) had a positive SLN. Both models were well calibrated across the full range of predicted probabilities and had similar external area under the receiver operating characteristic curves (AUC; MSKCC: 70.8%; 95% CI, 69.5-72.1 and limited MIA: 69.7%; 95% CI, 68.4-71.1). At a risk threshold of 5%, decision curve analysis indicated no added net benefit for either model compared to performing SLNB for all patients. At risk thresholds of 10% or higher, both models added net benefit compared to SLNB for all patients. The greatest benefit was observed in patients with T2 melanomas using a threshold of 10%; in that setting, the use of the nomograms led to a net reduction of 8 avoidable SLNBs per 100 patients for the MSKCC nomogram and 7 per 100 patients for the limited MIA nomogram compared to a strategy of SLNB for all. Conclusions and Relevance: This study confirmed the statistical performance of both the MSKCC and limited MIA models in a large, nationally representative data set. However, decision curve analysis demonstrated that using the models only improved selection for SLNB compared to biopsy in all patients when a risk threshold of at least 7% was used, with the greatest benefit seen for T2 melanomas at a threshold of 10%. Care should be taken when using these nomograms to guide selection for SLNB at the lowest thresholds.

Role of Concurrent Ultrasound Surveillance of Sentinel Node-Positive Node Fields in Melanoma Patients Having Routine Cross-Sectional Imaging.

PURPOSE: In sentinel node-positive (SN+ve) melanoma patients, active surveillance with regular ultrasound examination of the node field has become standard, rather than completion lymph node dissection (CLND). A proportion of these patients now receive adjuvant systemic therapy and have routine cross-sectional imaging (computed tomography [CT] or positron emission tomography [PET]/CT). The role of concurrent ultrasound (US) surveillance in these patients is unclear. The purpose of our study was to describe the modality of detection of nodal recurrence in SN+ve node fields. METHODS: SN+ve melanoma patients who did not undergo CLND treated at a single institution from January 1, 2016 to December 31, 2020 were included. RESULTS: A total of 225 SN+ve patients with a median follow-up of 23 months were included. Of these, 119 (53%) received adjuvant systemic therapy. Eighty (36%) developed a recurrence at any site; 24 (11%) recurred first in the SN+ve field, of which 12 (5%) were confirmed node field recurrence only at 2 months follow-up. The nodal recurrences were first detected by ultrasound in seven (3%), CT in seven (3%), and PET/CT in seven (3%) patients. All nodal recurrences evident on US were also evident on PET/CT and vice versa. CONCLUSIONS: The high rate of recurrences outside the node field and the identification of all US-detected nodal recurrences on concurrent cross-sectional imaging modalities suggest that routine concurrent ultrasound surveillance of the node-positive field may be unnecessary for SN+ve melanoma patients having routine cross-sectional imaging.

Prognostic Significance of Incipient Ulceration in Primary Cutaneous Melanoma.

Importance: Ulceration represents a key feature in cutaneous melanoma, contributing to staging according to the current American Joint Committee on Cancer (AJCC) system. However, cases with incipient ulceration do not quite fulfill the AJCC definition of ulceration and are consequently classified as nonulcerated, presenting interpretive difficulty for pathologists. The prognostic implication of incipient ulceration is uncertain. Objective: To evaluate the prognostic significance of incipient ulceration in cutaneous melanoma. Design, Setting, and Participants: This case-control study consisted of resected primary cutaneous melanomas diagnosed between 2005 and 2015, identified from the Melanoma Institute Australia research database and with slides available for review at Royal Prince Alfred Hospital. Slides were reviewed by pathologists experienced in the diagnosis of melanocytic lesions to identify cases (incipient ulceration) and controls (ulcerated or nonulcerated). Incipient ulceration cases were matched at a 1:2 ratio with nonulcerated and ulcerated controls, respectively. Study analysis was conducted from March to June 2023. Main Outcomes: Clinicopathological factors and clinical outcomes: overall survival (OS), melanoma-specific survival (MSS), and recurrence-free survival (RFS) were compared between cases and controls. Results: Of 2284 patients with melanoma identified, 340 patients (median [IQR] age, 69 [24-94] years; 136 [68%] men; median follow-up, 7.2 years) met the criteria. The matched cohort consisted of 40 cases of incipiently ulcerated melanoma matched 1:2 with 80 nonulcerated controls, and 80 ulcerated controls. The median (IQR) Breslow thickness differed significantly between cases and controls; 2.8 (1.7-4.1) mm for incipient cases compared with 1.0 (0.6-2.1) mm and 5.3 (3.5-8.0) mm for nonulcerated and ulcerated melanomas, respectively. Median (IQR) tumor mitotic rate was 5.0 (3.0-9.0) per mm2 in incipiently ulcerated cases compared with 1 (0-3.0) per mm2 in nonulcerated controls and 9 (5.0-14.0) per mm2 in ulcerated controls. Based on the matched cohorts, patients with nonulcerated tumors had significantly better OS (hazard ratio [HR], 0.49; 95% CI, 0.27-0.88; P = .02) and RFS (HR, 0.37; 95% CI, 0.22-0.64; P < .001) than patients with incipient ulceration. The RFS was significantly worse in ulcerated tumors compared with incipiently ulcerated cases (HR, 1.67; 95% CI, 1.07-2.60; P = .03). After adjusting for pathological factors, no statistically significant differences in clinical outcomes were observed between cases and either control group. Conclusions and Relevance: The findings of this case-control study indicate that incipient ulceration in a primary melanoma represents an adverse prognostic feature that should be noted by pathologists in their reports and considered in future guidelines.

Telehealth follow-up consultations for melanoma patients during the COVID-19 pandemic: Patient and clinician satisfaction.

INTRODUCTION: The COVID-19 pandemic caused rapid implementation of telehealth for melanoma follow-up care in Australia. This study explores Australian melanoma patients and clinicians' level of satisfaction with telehealth. METHODS: A cross-sectional study was conducted across three specialist melanoma centres in Sydney, Australia. Melanoma patients (all stages) and clinicians completed mixed methods surveys seeking socio-demographic and clinical information and questionnaires to assess satisfaction with telehealth. Additionally, patients completed measures of quality of life, fear of cancer recurrence and trust in their oncologist. Patients and clinicians provided open-ended responses to qualitative questions about their perceptions of telehealth. RESULTS: One hundred and fifteen patients and 13 clinicians responded to surveys. Telephone was used by 109 (95%) patients and 11 (85%) clinicians. Fifty-seven (50%) patients and nine (69%) clinicians preferred face-to-face consultations, 38 (33%) patients and 3 (23%) clinicians preferred a combination of face-to-face and telehealth consultations. Five (4%) patients and nil clinicians preferred telehealth consultations. Patients diagnosed with early-stage melanoma, using telehealth for the first time, who have lower trust in their oncologist, and having higher care delivery, communication and supportive care concerns were likely to report lower satisfaction with telehealth. Open-ended responses were consistent between patients and clinicians, who reported safety, convenience and improved access to care as major benefits, while identifying personal, interpersonal, clinical and system-related disadvantages. DISCUSSION: While telehealth has been widely implemented during COVID-19, the benefits identified by patients and clinicians may extend past the pandemic. Telehealth may be considered for use in conjunction with face-to-face consultations to provide melanoma follow-up care.

Uncovering the complex relationship between balding, testosterone and skin cancers in men.

Male-pattern baldness (MPB) is related to dysregulation of androgens such as testosterone. A previously observed relationship between MPB and skin cancer may be due to greater exposure to ultraviolet radiation or indicate a role for androgenic pathways in the pathogenesis of skin cancers. We dissected this relationship via Mendelian randomization (MR) analyses, using genetic data from recent male-only meta-analyses of cutaneous melanoma (12,232 cases; 20,566 controls) and keratinocyte cancers (KCs) (up to 17,512 cases; >100,000 controls), followed by stratified MR analysis by body-sites. We found strong associations between MPB and the risk of KC, but not with androgens, and multivariable models revealed that this relationship was heavily confounded by MPB single nucleotide polymorphisms involved in pigmentation pathways. Site-stratified MR analyses revealed strong associations between MPB with head and neck squamous cell carcinoma and melanoma, suggesting that sun exposure on the scalp, rather than androgens, is the main driver. Men with less hair covering likely explains, at least in part, the higher incidence of melanoma in men residing in countries with high ambient UV.

Formation of giant iron oxide-copper-gold deposits by superimposed episodic hydrothermal pulses.

Iron oxide-copper-gold (IOCG) deposits are a globally important source of copper, gold and critical commodities. Despite their relevance, IOCG deposits remain an ill-defined clan, with a range of characteristics that has complicated development of the general genetic model. Here we focus on the Candelaria IOCG deposit in Chile and reveal that by using micro-textural and compositional variations in actinolite, a common alteration mineral found in many IOCG deposits, we can constrain the evolution of these systems. We demonstrate that Candelaria formed by the superposition of at least two pulses of mineralization with a late Cu-rich event overprinting and superimposed over an early, and probably higher temperature, iron oxide-apatite (IOA) mineralization event. These distinct pulses were likely caused by episodic injections of magmatic-hydrothermal fluids from crystallizing magmas at depth. Our data provide empirical evidence of grain-to-deposit scale compositional and potentially temperature changes in an IOCG system. The results support the use of actinolite chemistry as a novel approach to understand the formation of IOCG deposits and a potential tool for vectoring in exploration.

Epidemiology, staging and management of mucosal melanoma of the head and neck: a narrative review.

BACKGROUND AND OBJECTIVE: Mucosal melanoma of the head and neck (MMHN) are rare, aggressive neoplasms of melanocyte origin that remain incompletely understood and have a poor prognosis, with high rates of locoregional recurrence and distant metastasis. Several recent studies having expanded understanding of MMHN, we undertook a review of the latest evidence pertaining to its epidemiology, staging, and management. METHODS: A literature search was conducted for peer-reviewed articles reporting and discussing the epidemiology, staging, and management of MMHN. PubMed, Medline, Embase and the Cochrane Library were searched to identify relevant publications. KEY CONTENT AND FINDINGS: MMHN remains an uncommon disease. The current TNM staging system for MMHN provides inadequate risk stratification, and consideration of an alternative staging model such as one based on a nomogram may be justifiable. Tumour resection with clear histological margins remains the cornerstone of optimal treatment. Adjuvant radiotherapy may improve locoregional control but does not appear to affect survival. Immune checkpoint inhibitors and c-KIT inhibitors demonstrate promising efficacy in patients with advanced or unresectable mucosal melanomas, and warrant further research exploring the utility of combination therapies. Their roles as adjuvant therapies have not been determined. The efficacy of neoadjuvant systemic therapy is also not yet clear, although early results suggest that it may improve outcomes. CONCLUSIONS: New insights into the epidemiology, staging and management of MMHN have transformed the standard of care for this rare malignancy. Nonetheless, the results of ongoing clinical trials and future prospective studies are required to better understand this aggressive disease and optimise its management.