NCCN Guidelines® Insights: Melanoma: Cutaneous, Version 2.2024.

The NCCN Guidelines for Cutaneous Melanoma (termed Melanoma: Cutaneous) provide multidisciplinary recommendations for diagnostic workup, staging, and treatment of patients. These NCCN Guidelines Insights focus on the update to neoadjuvant systemic therapy options and summarize the new clinical data evaluated by the NCCN panel for the recommended therapies in Version 2.2024 of the NCCN Guidelines for Cutaneous Melanoma.

Determinants of overall survival in patients with metastatic uveal melanoma.

BACKGROUND: Despite improvements in the treatment of primary uveal melanoma (UM), patients with metastatic disease continue to exhibit poor survival. METHODS: A retrospective review of metastatic UM patients at Yale (initial cohort) and Memorial Sloan Kettering (validation cohort) was conducted. Cox proportional hazards regression was used to determine baseline factors that are associated with overall survival, including sex, Eastern Cooperative Oncology Group (ECOG) Performance Status Scale, laboratory measurements, metastasis location, and use of anti-CTLA-4 and anti-PD-1 therapies. Differences in overall survival were analyzed using Kaplan-Meier analysis. RESULTS: A total of 89 patients with metastatic UM were identified; 71 and 18, in the initial and validation cohorts, respectively. In the initial cohort, median follow-up was 19.8 months (range, 2-127 months) and median overall survival was 21.8 months (95% CI, 16.6-31.3). Female sex, anti-CTLA-4, and anti-PD-1 therapy were associated with better survival outcomes with adjusted death hazard ratios (HRs) of 0.40 (95% CI, 0.20-0.78), 0.44 (0.20-0.97), and 0.42 (0.22-0.84), respectively, whereas development of hepatic metastases and ECOG score ≥1 (per 1 U/L) were associated with worse survival outcomes with HRs of 2.86 (1.28-7.13) and 2.84 (1.29-6.09), respectively. In both the initial and validation cohorts, use of immune checkpoint inhibitors was associated with improved overall survival after adjusting for sex and ECOG score, with death HRs of 0.22 (0.08-0.56) and 0.04 (0.002-0.26), respectively. CONCLUSIONS: Development of extrahepatic-only metastases, ECOG of 0, immune checkpoint therapy, and female sex were each associated with more than 2-fold reductions in risk of death. PLAIN LANGUAGE SUMMARY: Metastatic uveal melanoma patients face limited treatment options and poor survival rates. Results from this retrospective analysis indicate that immune checkpoint inhibitors, such as anti-CTLA-4 and anti-PD-1 therapies, were associated with improved survival outcomes. Factors such as extrahepatic-only metastases, better baseline performance status, and female sex contributed to a more than 2-fold reduction in death risk. These findings highlight the potential of immunotherapy in treating metastatic uveal melanoma.

Assessment of Micronuclei Frequency in the Peripheral Blood of Adult and Pediatric Patients Receiving Fractionated Total Body Irradiation.

The cytokinesis-block micronucleus (CBMN) assay is an established method for assessing chromosome damage in human peripheral blood lymphocytes resulting from exposure to genotoxic agents such as ionizing radiation. The objective of this study was to measure cytogenetic DNA damage and hematology parameters in vivo based on MN frequency in peripheral blood lymphocytes (PBLs) from adult and pediatric leukemia patients undergoing hematopoietic stem cell transplantation preceded by total body irradiation (TBI) as part of the conditioning regimen. CBMN assay cultures were prepared from fresh blood samples collected before and at 4 and 24 h after the start of TBI, corresponding to doses of 1.25 Gy and 3.75 Gy, respectively. For both age groups, there was a significant increase in MN yields with increasing dose (p < 0.05) and dose-dependent decrease in the nuclear division index (NDI; p < 0.0001). In the pre-radiotherapy samples, there was a significantly higher NDI measured in the pediatric cohort compared to the adult due to an increase in the percentage of tri- and quadri-nucleated cells scored. Complete blood counts with differential recorded before and after TBI at the 24-h time point showed a rapid increase in neutrophil (p = 0.0001) and decrease in lymphocyte (p = 0.0006) counts, resulting in a highly elevated neutrophil-to-lymphocyte ratio (NLR) of 14.45 ± 1.85 after 3.75 Gy TBI (pre-exposure = 4.62 ± 0.49), indicating a strong systemic inflammatory response. Correlation of the hematological cell subset counts with cytogenetic damage, indicated that only the lymphocyte subset survival fraction (after TBI compared with before TBI) showed a negative correlation with increasing MN frequency from 0 to 1.25 Gy (r = -0.931; p = 0.007). Further, the data presented here indicate that the combination of CBMN assay endpoints (MN frequency and NDI values) and hematology parameters could be used to assess cytogenetic damage and early hematopoietic injury in the peripheral blood of leukemia patients, 24 h after TBI exposure.

NCCN Guidelines® Insights: Melanoma: Cutaneous, Version 2.2021.

Over the past few years, the NCCN Guidelines for Melanoma: Cutaneous have been expanded to include pathways for treatment of microscopic satellitosis (added in v2.2020), and the following Principles sections: Molecular Testing (added in v2.2019), Systemic Therapy Considerations (added in v2.2020), and Brain Metastases Management (added in v3.2020). The v1.2021 update included additional modifications of these sections and notable revisions to Principles of: Pathology, Surgical Margins for Wide Excision of Primary Melanoma, Sentinel Lymph Node Biopsy, Completion/Therapeutic Lymph Node Dissection, and Radiation Therapy. These NCCN Guidelines Insights discuss the important changes to pathology and surgery recommendations, as well as additions to systemic therapy options for patients with advanced disease.

Improved survival in women versus men with merkel cell carcinoma.

BACKGROUND: Studies have observed that women have better outcomes than men in melanoma, but less is known about the influence of sex differences on outcomes for other aggressive cutaneous malignancies. OBJECTIVE: To investigate whether women and men have disparate outcomes in Merkel cell carcinoma (MCC). METHODS: Patients with nonmetastatic MCC undergoing surgery and lymph node evaluation were identified from the National Cancer Database (NCDB) and the Surveillance, Epidemiology, and End Results (SEER) database. Kaplan-Meier analysis and Cox proportional hazards regression models were used for overall survival, and competing-risks analysis and Fine-Gray models were used for cause-specific and other-cause mortality. RESULTS: The NCDB cohort (n = 4178) included 1516 (36%) women. Women had a consistent survival advantage compared with men in propensity score-matched analysis (66.0% vs 56.8% at 5 years, P < .001) and multivariable Cox regression (hazard ratio, 0.68; 95% confidence interval, 0.61-0.75; P < .001). Similarly, women had a survival advantage in the SEER validation cohort (n = 1202) with 457 (38.0%) women, which was entirely due to differences in MCC-specific mortality (5-year cumulative incidence: 16.4% vs 26.7%, P = .002), with no difference in other-cause mortality (16.8% vs 17.8%, P = .43) observed in propensity score-matched patients. LIMITATIONS: Potential selection bias from a retrospective data set. CONCLUSION: In MCC, women have improved survival compared with men, driven by MCC-related mortality.

In vivo imaging characterization of basal cell carcinoma and cutaneous response to high-dose ionizing radiation therapy: A prospective study of reflectance confocal microscopy, dermoscopy, and ultrasonography.

BACKGROUND: Radiation therapy (RT) is a treatment option for select skin cancers. The histologic effects of RT on normal skin or skin cancers are not well characterized. Dermoscopy, high-frequency ultrasonography (HFUS), and reflectance confocal microscopy (RCM) are noninvasive imaging modalities that may help characterize RT response. OBJECTIVES: To describe changes in the tumor and surrounding skin of patients with basal cell carcinoma (BCC) treated with RT. METHODS: The study was conducted between 2014 and 2018. Patients with biopsy-proven BCCs were treated with 42 Gy in 6 fractions using a commercially available brachytherapy device. Dermoscopy, HFUS, and RCM were performed before treatment and at 6 weeks, 3 months, and 12 months after RT. RESULTS: A total of 137 imaging assessments (RCM + dermoscopy + HFUS) were performed in 12 patients. BCC-specific features were present in 81.8%, 91%, and 17% of patients imaged with dermoscopy, RCM, and HFUS at baseline, respectively, before treatment. After treatment, the resolution of these features was noted in 33.4%, 91.7%, and 100% of patients imaged with the respective modalities. No recurrences were seen after a mean of 31.7 months of follow-up. LIMITATIONS: Small sample size and no histopathologic correlation. CONCLUSION: Dermoscopy and HFUS were not as reliable as RCM at characterizing BCC RT response.

A phase 2 clinical trial assessing the efficacy and safety of pembrolizumab and radiotherapy in patients with metastatic triple-negative breast cancer.

BACKGROUND: The current study was conducted to evaluate the efficacy and safety of pembrolizumab-mediated programmed cell death protein 1 inhibition plus radiotherapy (RT) in patients with metastatic triple-negative breast cancer who were unselected for programmed death-ligand 1 expression. METHODS: The current study was a single-arm, Simon 2-stage, phase 2 clinical trial that enrolled a total of 17 patients with a median age of 52 years (range, 37-73 years). An RT dose of 3000 centigrays (cGy) was delivered in 5 daily fractions. Pembrolizumab was administered intravenously at a dose of 200 mg within 3 days of the first RT fraction, and then every 3 weeks ± 3 days until disease progression. The median follow-up was 34.5 weeks (range, 2.1-108.3 weeks). The primary endpoint of the current study was the overall response rate (ORR) at week 13 in patients with unirradiated lesions measured using Response Evaluation Criteria in Solid Tumors (RECIST; version 1.1). Secondary endpoints included safety and progression-free survival. Exploratory objectives were to identify biomarkers predictive of ORR and progression-free survival. RESULTS: The ORR for the entire cohort was 17.6% (3 of 17 patients; 95% CI, 4.7%-44.2%), with 3 complete responses (CRs), 1 case of stable disease, and 13 cases of progressive disease. Eight patients died prior to week 13 due to disease progression. Among the 9 women assessed using RECIST version 1.1 at week 13, 3 (33%) achieved a CR, with a 100% reduction in tumor volume outside of the irradiated portal. The CRs were durable for 18 weeks, 20 weeks, and 108 weeks, respectively. The most common grade 1 to 2 toxicity (assessed according to the National Cancer Institute Common Terminology Criteria for Adverse Events, version 4.0) was dermatitis (29%). Four grade 3 adverse events were attributed to pembrolizumab: fatigue, lymphopenia, and infection. No were no grade 4 adverse events or treatment-related deaths reported. CONCLUSIONS: The combination of pembrolizumab and RT was found to be safe and demonstrated encouraging activity in patients with poor-prognosis, metastatic, triple-negative breast cancer who were unselected for programmed death-ligand 1 expression. Larger clinical trials of checkpoint blockade plus RT with predictive biomarkers of response are needed.

Management of primary skin cancer during a pandemic: Multidisciplinary recommendations.

During the coronavirus disease 2019 (COVID-19) pandemic, providers and patients must engage in shared decision making regarding the pros and cons of early versus delayed interventions for localized skin cancer. Patients at highest risk of COVID-19 complications are older; are immunosuppressed; and have diabetes, cancer, or cardiopulmonary disease, with multiple comorbidities associated with worse outcomes. Physicians must weigh the patient's risk of COVID-19 complications in the event of exposure against the risk of worse oncologic outcomes from delaying cancer therapy. Herein, the authors have summarized current data regarding the risk of COVID-19 complications and mortality based on age and comorbidities and have reviewed the literature assessing how treatment delays affect oncologic outcomes. They also have provided multidisciplinary recommendations regarding the timing of local therapy for early-stage skin cancers during this pandemic with input from experts at 11 different institutions. For patients with Merkel cell carcinoma, the authors recommend prioritizing treatment, but a short delay can be considered for patients with favorable T1 disease who are at higher risk of COVID-19 complications. For patients with melanoma, the authors recommend delaying the treatment of patients with T0 to T1 disease for 3 months if there is no macroscopic residual disease at the time of biopsy. Treatment of tumors ≥T2 can be delayed for 3 months if the biopsy margins are negative. For patients with cutaneous squamous cell carcinoma, those with Brigham and Women's Hospital T1 to T2a disease can have their treatment delayed for 2 to 3 months unless there is rapid growth, symptomatic lesions, or the patient is immunocompromised. The treatment of tumors ≥T2b should be prioritized, but a 1-month to 2-month delay is unlikely to worsen disease-specific mortality. For patients with squamous cell carcinoma in situ and basal cell carcinoma, treatment can be deferred for 3 months unless the individual is highly symptomatic.

Intravitreous Cutaneous Metastatic Melanoma in the Era of Checkpoint Inhibition: Unmasking and Masquerading.

PURPOSE: Cutaneous melanoma metastatic to the vitreous is very rare. This study investigated the clinical findings, treatment, and outcome of patients with metastatic cutaneous melanoma to the vitreous. Most patients received checkpoint inhibition for the treatment of systemic disease, and the significance of this was explored. DESIGN: Multicenter, retrospective cohort study. PARTICIPANTS: Fourteen eyes of 11 patients with metastatic cutaneous melanoma to the vitreous. METHODS: Clinical records, including fundus photography and ultrasound results, were reviewed retrospectively, and relevant data were recorded for each patient eye. MAIN OUTCOME MEASURES: Clinical features at presentation, ophthalmic and systemic treatments, and outcomes. RESULTS: The median age at presentation of ophthalmic disease was 66 years (range, 23-88 years), and the median follow-up from diagnosis of ophthalmic disease was 23 months. Ten of 11 patients were treated with immune checkpoint inhibition at some point in the treatment course. The median time from starting immunotherapy to ocular symptoms was 17 months (range, 4.5-38 months). Half of eyes demonstrated amelanotic vitreous debris. Five eyes demonstrated elevated intraocular pressure, and 4 eyes demonstrated a retinal detachment. Six patients showed metastatic disease in the central nervous system. Ophthalmic treatment included external beam radiation (30-40 Gy) in 6 eyes, intravitreous melphalan (10-20 µg) in 4 eyes, enucleation of 1 eye, and local observation while receiving systemic treatment in 2 eyes. Three eyes received intravitreous bevacizumab for neovascularization. The final Snellen visual acuity ranged from 20/20 to no light perception. CONCLUSIONS: The differential diagnosis of vitreous debris in the context of metastatic cutaneous melanoma includes intravitreal metastasis, and this seems to be particularly apparent during this era of treatment with checkpoint inhibition. External beam radiation, intravitreous melphalan, and systemic checkpoint inhibition can be used in the treatment of ophthalmic disease. Neovascular glaucoma and retinal detachments may occur, and most eyes show poor visual potential. Approximately one quarter of patients demonstrated ocular disease that preceded central nervous system metastasis. Patients with visual symptoms or vitreous debris in the context of metastatic cutaneous melanoma would benefit from evaluation by an ophthalmic oncologist.

Restaging [18F] fludeoxyglucose positron emission tomography/computed tomography scan in recurrent cutaneous squamous cell carcinoma: Diagnostic performance and prognostic significance.

BACKGROUND: There are no specific recommendations for [18F] fludeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) in assessing recurrent cutaneous squamous cell carcinoma (cSCC). OBJECTIVE: To evaluate FDG-PET/CT in recurrent cSCC. METHODS: FDG-PET/CT scans were retrospectively reviewed. Sites of abnormal uptake were noted and correlated with biopsy/histopathology studies, where available, and with follow-up imaging or clinical data in others. Comparison with available CT/magnetic resonance imaging was performed. The prognostic significance of PET/CT parameters was evaluated, and PET/CT-based change in management was recorded. RESULTS: A total of 115 FDG-PET/CT scans were analyzed in 100 consecutive patients with cSCC. Of these, 96 (84%) scans were positive for recurrence, and 25 showed distant metastases. PET/CT detected unsuspected disease sites in 39 of 115 scans (34%), locoregional disease in 14, distant metastases in 11, both locoregional disease and distant metastases in 8, additional local cutaneous disease in 5, and second malignancy in 1. Comparison of 78 PET/CT scans with available CT/magnetic resonance imaging showed 37 additional abnormalities on 23 PET/CT scans, predominantly including skin/subcutaneous lesions and nodes. PET/CT led to change in management in 28% of patients. On univariate/multivariate analysis, increased number of FDG-positive lesions and lung metastases on PET/CT was associated with increased risk of death/disease progression. LIMITATIONS: Retrospective study. CONCLUSIONS: FDG-PET/CT was sensitive in detecting recurrent disease in cSCC, led to change in management for 28% of patients, and proved to be of prognostic value.

Sebaceous carcinoma: evidence-based clinical practice guidelines.

Sebaceous carcinoma usually occurs in adults older than 60 years, on the eyelid, head and neck, and trunk. In this Review, we present clinical care recommendations for sebaceous carcinoma, which were developed as a result of an expert panel evaluation of the findings of a systematic review. Key conclusions were drawn and recommendations made for diagnosis, first-line treatment, radiotherapy, and post-treatment care. For diagnosis, we concluded that deep biopsy is often required; furthermore, differential diagnoses that mimic the condition can be excluded with special histological stains. For treatment, the recommended first-line therapy is surgical removal, followed by margin assessment of the peripheral and deep tissue edges; conjunctival mapping biopsies can facilitate surgical planning. Radiotherapy can be considered for cases with nerve or lymph node involvement, and as the primary treatment in patients who are ineligible for surgery. Post-treatment clinical examination should occur every 6 months for at least 3 years. No specific systemic therapies for advanced disease can be recommended, but targeted therapies and immunotherapies are being developed.

Basal cell carcinoma: Epidemiology; pathophysiology; clinical and histological subtypes; and disease associations.

As the most common human cancer worldwide and continuing to increase in incidence, basal cell carcinoma is associated with significant morbidity and cost. Continued advances in research have refined both our insight and approach to this seemingly ubiquitous disease. This 2-part continuing medical education article will provide a comprehensive and contemporary review of basal cell carcinoma. The first article in this series describes our current understanding of this disease regarding epidemiology, cost, clinical and histopathologic presentations, carcinogenesis, natural history, and disease associations.

Basal cell carcinoma: Contemporary approaches to diagnosis, treatment, and prevention.

As the most common human cancer worldwide and continuing to increase in incidence, basal cell carcinoma is associated with significant morbidity and cost. Continued advances in research have refined both our insight and approach to this seemingly ubiquitous disease. This 2-part continuing medical education series provides a comprehensive and contemporary review of basal cell carcinoma. The second article in this series will present both the current standard of care and newly developed approaches to diagnosis, treatment, and prevention of this disease.

New NCCN Guidelines for Uveal Melanoma and Treatment of Recurrent or Progressive Distant Metastatic Melanoma.

The NCCN Guidelines Panel for Melanoma debuted new guidelines for uveal melanoma at the NCCN 23rd Annual Conference. Although uveal melanoma and cutaneous melanoma share the same name, they do have different characteristics and treatments. The NCCN Guidelines describe how tumor size guides therapeutic options, which for most tumors is radiotherapy. Predictors of melanoma-related mortality include advanced age, larger tumor size, and histopathologic and molecular features. The NCCN Guidelines for Cutaneous Melanoma have not changed notably, but adjuvant therapy with immunotherapies is now recommended. The best second-line treatment in the metastatic setting remains unclear.

Tumor Board Conferences for Multidisciplinary Skin Cancer Management: A Survey of US Cancer Centers.

Background: Tumor board conferences (TBCs) are used by oncologic specialists to review patient cases, exchange knowledge, and discuss options for cancer management. These multidisciplinary meetings are often a cornerstone of treatment at leading cancer centers and are required for accreditation by certain groups, such as the American College of Surgeons' Commission on Cancer. Little is known regarding skin cancer TBCs. The objective of this study was to characterize the structure, function, and impact of existing skin cancer TBCs in the United States. Methods: A cross-sectional online survey was administered to physician leaders of skin cancer TBCs at NCI-designated Comprehensive and Clinical Cancer Centers. Results: Of the 59 centers successfully contacted, 14 (24%) reported not having a conference where skin cancer cases were discussed, and 45 (76%) identified 53 physician leaders. A total of 38 physicians (72%) completed the survey. Half of the meeting leaders were medical and/or surgical oncologists, and dermatologists led one-third of meetings. TBCs had a moderate to significant impact on patient care according to 97% of respondents. All respondents indicated that the meetings enhanced communication among physicians and provided an opportunity for involved specialists and professionals to discuss cases. The most frequently cited barrier to organizing TBCs was determining a common available date and time for attendees (62%). The most common suggestion for improvement was to increase attendance, specialists, and/or motivation. Conclusions: Results showed overall consistency in meeting structure but variability in function, which may be a reflection of institutional resources and investment in the conference. Future directions include defining metrics to evaluate changes in diagnosis or management plan after tumor board discussion, attendance, clinical trial enrollment, and cost analysis. Results of this survey may aid other institutions striving to develop and refine skin cancer TBCs.

A Serum Small Molecule Biosignature of Radiation Exposure from Total Body Irradiated Patients.

The potential for radiological accidents and nuclear terrorism has increased the need for the development of new rapid biodosimetry methods. In addition, in a clinical setting the issue of an individual's radiosensitivity should be taken into consideration during radiotherapy. We utilized metabolomics and lipidomics to investigate changes of metabolites in serum samples following exposure to total body ionizing radiation in humans. Serum was collected prior to irradiation, at 3-8 h after a single dose of 1.25-2 Gy, and at 24 h with a total delivered dose of 2-3.75 Gy. Metabolomics revealed perturbations in glycerophosphocholine, phenylalanine, ubiquinone Q2, and oxalic acid. Alterations were observed in circulating levels of lipids from monoacylglycerol, triacylglycerol, phosphatidylcholine, and phosphatidylglycerol lipid classes. Polyunsaturated fatty acids were some of the most dysregulated lipids, with increased levels linked to proinflammatory processes. A targeted metabolomics approach for eicosanoids was also employed. The results showed a rapid response for proinflammatory eicosanoids, with a dampening of the signal at the later time point. Sex differences were observed in the markers from the untargeted approach but not the targeted method. The ability to identify and quantify small molecules in blood can therefore be utilized to monitor radiation exposure in human populations.

Corticosteroids compromise survival in glioblastoma.

Glioblastoma is the most common and most aggressive primary brain tumour. Standard of care consists of surgical resection followed by radiotherapy and concomitant and maintenance temozolomide (temozolomide/radiotherapy→temozolomide). Corticosteroids are commonly used perioperatively to control cerebral oedema and are frequently continued throughout subsequent treatment, notably radiotherapy, for amelioration of side effects. The effects of corticosteroids such as dexamethasone on cell growth in glioma models and on patient survival have remained controversial. We performed a retrospective analysis of glioblastoma patient cohorts to determine the prognostic role of steroid administration. A disease-relevant mouse model of glioblastoma was used to characterize the effects of dexamethasone on tumour cell proliferation and death, and to identify gene signatures associated with these effects. A murine anti-VEGFA antibody was used in parallel as an alternative for oedema control. We applied the dexamethasone-induced gene signature to The Cancer Genome Atlas glioblastoma dataset to explore the association of dexamethasone exposure with outcome. Mouse experiments were used to validate the effects of dexamethasone on survival in vivo Retrospective clinical analyses identified corticosteroid use during radiotherapy as an independent indicator of shorter survival in three independent patient cohorts. A dexamethasone-associated gene expression signature correlated with shorter survival in The Cancer Genome Atlas patient dataset. In glioma-bearing mice, dexamethasone pretreatment decreased tumour cell proliferation without affecting tumour cell viability, but reduced survival when combined with radiotherapy. Conversely, anti-VEGFA antibody decreased proliferation and increased tumour cell death, but did not affect survival when combined with radiotherapy. Clinical and mouse experimental data suggest that corticosteroids may decrease the effectiveness of treatment and shorten survival in glioblastoma. Dexamethasone-induced anti-proliferative effects may confer protection from radiotherapy- and chemotherapy-induced genotoxic stress. This study highlights the importance of identifying alternative agents such as vascular endothelial growth factor antagonists for managing oedema in glioblastoma patients. Beyond the established adverse effect profile of protracted corticosteroid use, this analysis substantiates the request for prudent and restricted use of corticosteroids in glioblastoma.

Prognosis of Mucosal, Uveal, Acral, Nonacral Cutaneous, and Unknown Primary Melanoma From the Time of First Metastasis.

BACKGROUND: Subtypes of melanoma, such as mucosal, uveal, and acral, are believed to result in worse prognoses than nonacral cutaneous melanoma. After a diagnosis of distant metastatic disease, however, the overall survival of patients with mucosal, uveal, acral, nonacral cutaneous, and unknown primary melanoma has not been directly compared. MATERIALS AND METHODS: We conducted a single-center, retrospective analysis of 3,454 patients with melanoma diagnosed with distant metastases from 2000 to 2013, identified from a prospectively maintained database. We examined melanoma subtype, date of diagnosis of distant metastases, age at diagnosis of metastasis, gender, and site of melanoma metastases. RESULTS: Of the 3,454 patients (237 with mucosal, 286 with uveal, 2,292 with nonacral cutaneous, 105 with acral cutaneous, and 534 with unknown primary melanoma), 2,594 died. The median follow-up was 46.1 months. The median overall survival for those with mucosal, uveal, acral, nonacral cutaneous, and unknown primary melanoma was 9.1, 13.4, 11.4, 11.7, and 10.4 months, respectively. Patients with uveal melanoma, cutaneous melanoma (acral and nonacral), and unknown primary melanoma had similar survival, but patients with mucosal melanoma had worse survival. Patients diagnosed with metastatic melanoma in 2006-2010 and 2011-2013 had better overall survival than patients diagnosed in 2000-2005. In a multivariate model, patients with mucosal melanoma had inferior overall survival compared with patients with the other four subtypes. CONCLUSION: Additional research and advocacy are needed for patients with mucosal melanoma because of their shorter overall survival in the metastatic setting. Despite distinct tumor biology, the survival was similar for those with metastatic uveal melanoma, acral, nonacral cutaneous, and unknown primary melanoma. IMPLICATIONS FOR PRACTICE: Uveal, acral, and mucosal melanoma are assumed to result in a worse prognosis than nonacral cutaneous melanoma or unknown primary melanoma. No studies, however, have been conducted assessing the overall survival of patients with these melanoma subtypes starting at the time of distant metastatic disease. The present study found that patients with uveal, acral, nonacral cutaneous, and unknown primary melanoma have similar overall survival after distant metastases have been diagnosed. These findings provide information for oncologists to reconsider previously held assumptions and appropriately counsel patients. Patients with mucosal melanoma have worse overall survival and are thus a group in need of specific research and advocacy.