Sex-Based Differences in Melanoma Survival in a Contemporary Patient Cohort

The Effect of Body Mass Index on Melanoma Biology, Immunotherapy Efficacy, and Clinical Outcomes: A Narrative Review

Recent studies indicate that a higher body mass index (BMI) might correlate with improved responses to melanoma treatment, especially with immune checkpoint inhibitors (ICIs), despite the general association of obesity with an increased risk of cancer and higher mortality rates. This review examines the paradoxical relationship between BMI and clinical outcomes in melanoma patients by exploring molecular links, the efficacy of immunotherapy, and patient survival outcomes. Our comprehensive literature search across the PubMed and Embase databases revealed a consistent pattern: increased BMI is associated with a better prognosis in melanoma patients undergoing ICI treatment. This "obesity paradox" might be explained by the metabolic and immunological changes in obesity, which could enhance the effectiveness of immunotherapy in treating melanoma. The findings highlight the complexity of the interactions between obesity and melanoma, suggesting that adipose tissue may modulate the immune response and treatment sensitivity favorably. Our review highlights the need for personalized treatment strategies that consider the metabolic profiles of patients and calls for further research to validate BMI as a prognostic factor in clinical settings. This nuanced approach to the obesity paradox in melanoma could significantly impact treatment planning and patient management.

Characteristics and variations in young adults with cutaneous melanoma: A national cancer database analysis

BACKGROUND AND OBJECTIVES

Many cancers in young adulthood differ in terms of biology, histologic variation, and prognosis compared to cancer in other older age groups. Differences in cutaneous melanoma among young adults compared to other older age groups, as well as between sexes in young adults are not well studied.

METHODS

The National Cancer Database was queried for patients diagnosed with cutaneous melanoma between 2004 and 2017. Patient characteristics, disease factors, and treatment were stratified by age-based cohorts and compared using standard univariate statistics. The Kaplan-Meier method and log-rank tests were used to evaluate overall survival (OS) between age-based cohorts and young adult sexes.

RESULTS

Of the 329 765 patients identified, 10.5% were between 18 and 39 years of age at diagnosis. Compared with other older age groups, young adult patients were more likely to be female and uninsured with higher proportions of superficial spreading melanoma, melanoma of the trunk and extremities, and earlier-stage disease. Young adults had improved OS compared to other older age groups. Young male patients had a greater proportion of no insurance, nodular melanoma, higher-stage disease, and decreased OS compared to young female patients. Additionally, while the 5-year OS difference was statistically significant across all stages of disease between young males and females, the clinical significance is likely limited to later stages.

CONCLUSIONS

Age and sex-specific differences in cutaneous melanoma highlight distinct patterns and characteristics, emphasizing the need for tailored approaches to screening, diagnosis, and treatment.

Distinct presentation of melanoma in Black patients may inform strategies to improve outcomes

INTRODUCTION

Melanoma guidelines stem largely from data on non-Hispanic White (NHW) patients. We aimed to identify features of melanoma within non-Hispanic Black (NHB) patients to inform strategies for earlier detection and treatment.

METHODS

From 2004 to 2019 Surveillance, Epidemiology, and End Results (SEER) data, we identified nonmetastatic melanoma patients with known TN category and race. Kaplan-Meier cancer-specific survival (CSS) estimates and multivariable Cox proportional hazard modeling analyses were performed.

RESULTS

Of 492 597 patients, 1499 (0.3%) were NHB, who were younger (21% vs. 17% age <50) and more commonly female (54% vs. 41%) than NHW, both p < 0.0005. For NHBs, lower extremity was the most common site (52% vs. 15% for NHWs, p < 0.0001), T category was higher (55% Tis-T1 vs. 82%; 27% T3-T4 vs. 8%, p < 0.0001) and stage at presentation was higher (19% Stage III, vs. 6%, p < 0.0001). Within the NHB cohort, males were older, and more often node-positive than females. Five-year Stage III CSS was 42% for NHB males versus 71% for females, adjusting for age and clinical nodal status (hazard ratio 2.48).

CONCLUSIONS

NHB melanoma patients presented with distinct tumor characteristics. NHB males with Stage III disease had inferior CSS. Focus on this high-risk patient cohort to promote earlier detection and treatment may improve outcomes.

Sex-Based Differences in Melanoma Survival Improvement from 2004 to 2018

Background: Melanoma is the deadliest form of skin cancer and its incidence and mortality vary by sex, age, race, and socioeconomic status. Relatively few studies, however, have characterized disparities in survival improvement across these demographic groups in melanoma.

METHODS

Survival data from the Surveillance, Epidemiology, and End Results (SEER) database were obtained from 2004 to 2018. The compiled data were analyzed for cancer-specific survival (CSS) to produce multivariable Cox regressions that estimate sex-based survival disparities across patient demographic groups. Additionally, time-to-progression and survival analyses were conducted for a cohort of patients with carcinoma-in situ (CIS) that developed into melanoma.

RESULTS

In both female and male patients, melanoma diagnosis in more recent years (2014-2018 versus 2004-2008) was associated with an improved CSS, with females demonstrating an HR of 0.55 (95% CI: 0.49-0.60) and males demonstrating an HR of 0.49 (0.46-0.53). The trend remained consistent upon analyzing the effects of both sex and race on survival improvement for White and Hispanic males and females, but the results were not significant for Black and Asian patients. Joint sex and age analysis demonstrated significant reductions in HR across all age groups for female and male patients with a diagnosis in more recent years. Analysis of lesions progressing from CIS to melanoma (high-risk CIS) demonstrated an increased OR for males over females (OR: 1.70; 95% CI: 1.55-1.85), while survival analysis demonstrated no difference between sexes in the HR. Finally, for male patients, high-risk CIS demonstrated worse CSS compared to female patients with high-risk CIS (OR: 1.43; 95% CI: 1.15-1.79).

CONCLUSION

Overall, melanoma survival has improved in recent years, though some patient subgroups have experienced a lower improvement in survival from 2004 to 2018.

Multipeptide vaccines for melanoma in the adjuvant setting: long-term survival outcomes and post-hoc analysis of a randomized phase II trial

The critical roles of CD4+ T cells have been understudied for cancer vaccines. Here we report long-term clinical outcomes of a randomized multicenter phase II clinical trial (NCT00118274), where patients with high-risk melanoma received a multipeptide vaccine targeting CD8+ T cells (12MP) and were randomized to receive either of two vaccines for CD4+ (helper) T cells: 6MHP (6 melanoma-specific helper peptides), or tet (a nonspecific helper peptide from tetanus toxoid). Cyclophosphamide (Cy) pre-treatment was also assessed. Primary outcomes for T cell responses to 12MP, 6MHP, and tet were previously reported, suggesting immunogenicity of both vaccines but that CD8 T cell responses to 12MP were lower when tet was replaced with 6MHP. Here, in post-hoc analyses, we report durable prolongation of overall survival by adding 6MHP instead of tet. That benefit was experienced only by male patients. A favorable interaction of 6MHP and Cy is also suggested. Multivariable Cox regression analysis of the intent-to-treat population identify vaccine arm (12MP + 6MHP+Cy) and patient sex (male) as the two significant predictors of enhanced survival. These findings support the value of adding cognate T cell help to cancer vaccines and also suggest a need to assess the impact of patient sex on immune therapy outcomes.

Do age at diagnosis, tumour thickness and tumour site explain sex differences in melanoma survival? A causal mediation analysis using cancer registry data

Women diagnosed with melanoma have better survival than men, but little is known about potential intervention targets to reduce this survival gap by sex. We conducted a population-based study using Victorian Cancer Registry data including 5833 women and 6780 men aged 15 to 70 years when diagnosed with first primary melanoma between 2007 and 2015. Deaths to the end of 2020 were identified through linkage to the Victorian and national death registries. We estimated the effect of age at diagnosis, tumour thickness and tumour site on reducing the melanoma-specific survival gap by sex (ie, interventional indirect effects [IIEs]) on risk difference (RD) scale. Compared to women, there were 211 (95% CI: 145-278) additional deaths per 10 000 in men within 5 years following diagnosis. We estimated that 44% of this gap would be reduced by a hypothetical intervention shifting the distribution of melanoma thickness in men to be the same as that observed for women (IIEthickness RD 93 [95% CI: 75-118] per 10 000) and 20% by an intervention on tumour site (head and neck/trunk vs upper limb/lower limb; IIEsite RD 42 [95% CI: 15-72] per 10 000), while an intervention on age at diagnosis would have a negligible effect. Tumour thickness, tumour site and age at diagnosis mediated 65% of the effect of sex on 5-year melanoma survival in Victoria. Of these factors, tumour thickness had the most considerable mediating effect, suggesting that effective promotion of earlier detection of melanoma in men could potentially nearly halve the gap in melanoma-specific survival by sex.

The Burden of Thin Melanomas in Tuscany, Italy, 1985-2017: Age- and Sex-Specific Temporal Trends in Incidence and Mortality

A steady increase in the incidence and mortality burden correlated to thin melanomas (≤1 mm) has been reported in recent years in some international studies, but there is currently a paucity of data from the Mediterranean area. We aimed to describe the epidemiological characteristics of thin melanoma in Tuscany, Central Italy. A total of 6002 first cutaneous invasive melanomas occurring from 1985 to 2017 were selected for analysis; data were retrieved from the local population-based cancer registry. The standardized incidence rate was 15.0 per 100,000 in the population, higher among men than women (16.5 vs. 14.1). Incidence rates tended to increase over time across all age group-specific population strata, with annual percent changes moderately higher among men (+8.0%) than women (+6.9%), especially among the elderly. Among both sexes and in each age group, the trend toward increasing incidence rates was particularly strong for thin melanomas. Survival was better among women than men across all categories of thickness. Approximately 15% of deaths occurred among patients with thin lesions, with no major temporal changes in recent years. This study contributes to an improved understanding of melanoma epidemiology in Tuscany and underscores the need for primary prevention strategies tackling the growing burden of thin melanomas.

Survival in patients diagnosed with melanoma in situ compared to the general population. A Swedish population-based matched cohort study

Background

The incidence of melanoma in situ (MIS) is increasing even more rapidly than the incidence of cutaneous malignant melanoma (CMM). No previous studies have in detail investigated the survival in individuals diagnosed with MIS compared to the general population.

Methods

This population-based study included individuals with MIS diagnosed in Sweden between 2001 and 2010 and randomly selected MIS-free comparators matched on age, sex and county of residence. Exclusion criterion was a previous CMM. Data on socioeconomic status (SES) including educational level, income and marital status, comorbidity and cause of death were obtained from population-based registers. Overall survival (OS) was estimated by the Kaplan-Meier method. The mortality risk adjusted for SES and comorbidity was assessed by multivariable Cox regression analyses.

Findings

The survival analyses included 7963 cases and 39,662 comparators. Median age at MIS diagnosis were 63 (IQR 50-75) and 67 (IQR 57-76) years in women and men respectively. Median follow-up time was 120 months (IQR 102-152 months). In individuals with MIS, the ten-year OS was 77% (95% CI 0.76-0.78) compared to 72% (95% CI 0.72-0.73) in comparators. The MIS patients had a higher SES and lower comorbidity burden than the comparators. In a fully adjusted multivariable analysis, including 7772 cases and 38,103 comparators, the mortality was significantly lower in women with MIS (HR 0.88, 95% CI 0.82-0.94) compared to the background population. The corresponding estimate in men was HR 0.94 (95% CI 0.88-1.0). The risk of melanoma-related deaths during the study period was ten-fold higher in MIS patients.

Interpretation

Despite being at increased risk of developing CMM, MIS patients had a better OS compared to their matched comparators from the background population, findings which could not fully be explained by differences in SES and comorbidity. Our results are reassuring and should be communicated to patients who have been diagnosed with MIS.

Funding

Stiftelsen Onkologiska Klinikens i Uppsala Forskningsfond, Mats and Stefan Paulsson Trust, Medicon Village, Lund and Uppsala University Hospital (ALF).

Significant improvement in melanoma survival over the last decade: A Hungarian nationwide study between 2011 and 2019

BACKGROUND

Recent real-world studies have reported significant improvements in the survival of malignant melanoma in the past few years, mainly as a result of modern therapies. However, long-term survival data from Central Eastern European countries such as Hungary are currently lacking.

METHODS

This nationwide, retrospective study examined melanoma survival in Hungary between 2011-2019 using the databases of the National Health Insurance Fund (NHIF) and Central Statistical Office (CSO) of Hungary. Crude overall survival and age-standardized 5-year net survival as well as the association between age, sex and survival were calculated.

RESULTS

Between 2011 and 2019, 22,948 newly diagnosed malignant melanoma cases were recorded in the NHIF database (47.89% male, mean age: 60.75 years (SD: ±16.39)). Five-year overall survival was 75.40% (women: 80.78%; men: 69.52%). Patients diagnosed between 2017-2019 had a 20% lower risk of mortality compared to patients diagnosed between 2011-2012 (HR 0.80, 95% CI 0.73-0.89; p < 0.0001). Age-standardized 5-year net survival rates in 2011-2014 and 2015-2019 were 90.6% and 95.8%, respectively (women: 93.1% and 98.4%, men: 87.8% and 92.7%, respectively). The highest age-standardized 5-year net survival rates were found in the 0-39 age cohort (94.6% in the 2015-2019 period).

CONCLUSION

Hungary has similar melanoma survival rates to Western European countries. Based on net survival, the risk of dying of melanoma within 5 years was cut by more than half (55%) during the study period, which coincides with the successful implementation of awareness campaigns and the wide availability of modern therapies.

Clinical predictors of survival in real world practice in stage IV melanoma

BACKGROUND AND AIM

While studies continually identify new clinical prognostic factors in stage IV melanoma, the introduction of targeted and immunotherapies have revolutionised the prognosis of advanced melanoma since 2011. The study aims to investigate the prognostic significance of past and newly identified clinical factors in a contemporary cohort.

METHODS

A retrospective analysis of The Canberra Hospital melanoma database identified 161 patients with Stage IV melanoma between 2011 and 2017. Survival was analysed by demographics and clinical factors with chi-square tests to determine significance. Logistic binary regression was performed to test the independence of the clinical factors on predicting the survival outcome.

RESULTS

Overall, the 3-month, 6-month, 9-month, and 12-month stage IV melanoma survival rate of our cohort was 79%, 67%, 55%, and 45%, respectively. Age, sex, and BRAF mutation status were found to have no impact on survival, whereas M1d category of the American Joint Committee on Cancer (AJCC) staging (8th edition), neutrophil-lymphocyte ratio (NLR) >3, elevated serum LDH, more than three metastatic sites, brain metastases, poorer Eastern cooperative oncology group (ECOG) status were associated with poorer survival. Binary logistic regression test identified AJCC staging, NLR (cutoff score 3), LDH, and brain metastases as independent prognostic factors.

CONCLUSION

Most clinical factors investigated in this study were found to have a statistically significant impact on survival, with AJCC (8th edition) staging M1a-M1d, NLR (cutoff score 3), LDH, and brain metastases identified as independent prognostic factors in stage IV melanoma from a contemporary cohort treated with targeted therapies and immunotherapies.

Modeling the effects of genetic- and diet-induced obesity on melanoma progression in zebrafish

Obesity is a rising concern and associated with an increase in numerous cancers, often in a sex-specific manner. Preclinical models are needed to deconvolute the intersection between obesity, sex and melanoma. Here, we generated a zebrafish system that can be used as a platform for studying these factors. We studied how germline overexpression of Agrp along with a high-fat diet affects melanomas dependent on BRAFV600E and loss of p53. This revealed an increase in tumor incidence and area in male, but not female, obese fish, consistent with the clinical literature. We then determined whether this was further affected by additional somatic mutations in the clinically relevant genes rb1 or ptena/b. We found that the male obesogenic effect on melanoma was present with tumors generated with BRAF;p53;Rb1 but not BRAF;p53;Pten. These data indicate that both germline (Agrp) and somatic (BRAF, Rb1) mutations contribute to obesity-related effects in melanoma. Given the rapid genetic tools available in the zebrafish, this provides a high-throughput system to dissect the interactions of genetics, diet, sex and host factors in obesity-related cancers.

Cilt Kanserlerinin Ayırıcı Tanısında İnflamatuar Belirteçlerin Yeri

Aim: The purpose of this study was to evaluate the role of WBC count, NLR, LMR, PLR, Systemic immune-inflammation index (SII) [(platelet count X neutrophil count) \ lymphocyte count] and platelet count (Plt)×NLR in the differential diagnosis of basal cell carcinoma, squamous cell carcinoma, and malignant melanoma and to determine the effect of tumor type, prediction of lymph node metastasis at initial diagnosis and location on these inflammatory markers. Material and Method: Patients who underwent surgery for basal cell carcinoma, squamous cell carcinoma, or malignant melanoma were retrospectively screened. NLR, LMR, PLR, SII and Plt×NLR were calculated. Relationships between tumor type, prediction of lymph node metastasis at initial diagnosis, tumor localization and the inflammatory and hematological parameters of interest were investigated. Tumor location was classified as head and neck and others. Results: A total of 257 patients were included in the study. No statistically significant differences in WBC, NLR, PLR, LMR, SII or Plt×NLR were detected according to tumor location. The patients with squamous cell carcinoma had higher NLR, PRL, SII and Plt×NLR values than those with basal cell carcinoma. The risk of lymph node metastasis at the time of initial diagnosis was 10.3 times higher in patients with PLR levels of 180.7 and higher. The risk of lymph node metastasis detected at initial diagnosis was 8.9 times higher in patients with Plt×NLR of 747 and higher. The risk of lymph node metastasis detected at initial diagnosis was 7.1 times higher in patients with SII of 414 and higher. Conclusion: Inflammatory markers seem to be useful in the differential diagnosis of skin cancers and determined the risk of lymph node metastasis. However, it does not differ according to tumor localization.

An Epidemiologic Analysis of Melanoma Overdiagnosis in the United States, 1975-2017

The primary cause of the increase in melanoma incidence in the United States has been suggested to be overdiagnosis. We used Surveillance, Epidemiology, and End Result Program data from 1975 to 2017 to examine epidemiologic trends of melanoma incidence and mortality and better characterize overdiagnosis in white Americans. Over the 43-year period, incidence and mortality showed discordant temporal changes across population subgroups; trends most suggestive of overdiagnosis alone were present in females aged 55-74. Other groups showed mixed changes suggestive of overdiagnosis plus changes in underlying disease risk (decreasing risk in younger individuals and increasing risk in older males). Cohort effects were identified for male and female mortality and male incidence but were not as apparent for female incidence, suggesting that period effects have had a greater influence on changes in incidence over time in females. Encouraging trends included long-term declines in mortality in younger individuals and recent stabilization of invasive incidence in individuals aged 15-44 years and males aged 45-54 years. Melanoma in situ incidence, however, has continued to increase throughout the population. Overdiagnosis appears to be relatively greater in American females and for melanoma in situ.

Enhanced immune activation within the tumor microenvironment and circulation of female high-risk melanoma patients and improved survival with adjuvant CTLA4 blockade compared to males

BACKGROUND

We hypothesized that a gender difference in clinical response may exist to adjuvant CTLA4 blockade with ipilimumab versus high-dose IFNα (HDI). We investigated differences in candidate immune biomarkers in the circulation and tumor microenvironment (TME).

PATIENTS AND METHODS

This gender-based analysis was nested within the E1609 trial that tested adjuvant therapy with ipilimumab 3 mg/kg (ipi3) and 10 mg/kg (ipi10) versus HDI in high risk resected melanoma. We investigated gender differences in treatment efficacy with ipi3 and ipi10 versus HDI while adjusting for age, stage, ECOG performance (PS), ulceration, primary tumor status and lymph node number. Forest plots were created to compare overall survival (OS) and relapse free survival (RFS) between ipi and HDI. Gene expression profiling (GEP) was performed on tumors of 718 (454 male, 264 female) patients. Similarly, serum and peripheral blood mononuclear cells (PBMC) samples were tested for soluble and cellular biomarkers (N = 321 patients; 109 female and 212 male).

RESULTS

The subgroups of female, stage IIIC, PS = 1, ulcerated primary, in-transit metastasis demonstrated significant improvement in RFS and/or OS with ipi3 versus HDI. Female gender was significant for both OS and RFS and was further explored. In the RFS comparison, a multivariate Cox regression model including significant variables indicated a significant interaction between gender and treatment (P = 0.024). In peripheral blood, percentages of CD3+ T cells (P = 0.024) and CD3+ CD4+ helper T cells (P = 0.0001) were higher in females compared to males. Trends toward higher circulating levels of IL1β (P = 0.07) and IL6 (P = 0.06) were also found in females. Males had higher percentages of monocytes (P = 0.03) with trends toward higher percentages of regulatory T cells (T-reg). Tumor GEP analysis supported enhanced infiltration with immune cells including gammadelta T cells (P = 0.005), NK cells (P = 0.01), dendritic cells (P = 0.01), CD4+ T cells (P = 0.03), CD8+ T cells (P = 0.03) and T-reg (P = 0.008) in the tumors of females compared to males and a higher T-effector and IFNγ gene signature score (P = 0.0244).

CONCLUSION

Female gender was associated with adjuvant CTLA4 blockade clinical benefits and female patients were more likely to have evidence of type1 immune activation within the TME and the circulation. Trial registration ClinicalTrials.gov NCT01274338. Registered 11 January 2011, https://www.

CLINICALTRIALS

gov/ct2/show/NCT01274338.

ZIP9 Is a Druggable Determinant of Sex Differences in Melanoma

Melanoma and most other cancers occur more frequently and have worse prognosis in males compared with females. Although sex steroids are thought to be involved, classical androgen and estrogen receptors are not detectable in most melanomas. Here we show that testosterone promotes melanoma proliferation by activating ZIP9 (SLC39A9), a zinc transporter that is widely expressed in human melanoma but not intentionally targeted by available therapeutics. This testosterone activity required an influx of zinc, activation of MAPK, and nuclear translocation of YAP. FDA-approved inhibitors of the classical androgen receptor also inhibited ZIP9, thereby antagonizing the protumorigenic effects of testosterone in melanoma. In male mice, androgen receptor inhibitors suppressed growth of ZIP9-expressing melanomas but had no effect on isogenic melanomas lacking ZIP9 or on melanomas in females. These data suggest that ZIP9 might be effectively targeted in melanoma and other cancers by repurposing androgen receptor inhibitors that are currently approved only for prostate cancer. SIGNIFICANCE: Testosterone signaling through ZIP9 mediates some of the sex differences in melanoma, and drugs that target AR can be repurposed to block ZIP9 and inhibit melanoma in males.

Sex-specific survival benefit in early skin melanoma based on 8th AJCC edition: an analysis of data from the Surveillance, Epidemiology, and End Results (SEER) database

Background

Females have been found to have a survival benefit over males in past studies. However, in early melanoma patients, this benefit occurred in only those aged >60 years. The 8th edition of the American Joint Committee on Cancer (AJCC) readjusted the melanoma staging system, specifically stage I. This study aims to verify whether the sex-specific benefit in females exists in different age groups according to the 8th edition of the staging system.

Methods

We collected the data of individuals diagnosed with skin melanoma between 2004 and 2015 from the Surveillance, Epidemiology, and End Results (SEER) database. Based on the 8th edition of the melanoma staging system, patients diagnosed with pathological stage T1a-T3a, N0 and M0 melanoma were enrolled.

Results

A total of 115,576 patients, including 62,938 male patients and 52,638 female patients, were enrolled in this study. The survival rates of males and females in each stage from IA–IIA were significantly different (P<0.001). In further analyses of each age group, it was found that the proportions of patients with stages IA, IB and IIA were significantly different in each age group. Cox analysis showed that females with stage IA in all age groups benefited significantly, but those in stage IB benefited only when they were aged >60 years. In stage IIA patients, there were significant differences between the <50 and 61–70 years age groups.

Conclusions

Based on data from the SEER database, we found that according to the 8th edition of the AJCC melanoma staging system, females had a higher survival rate than males, and this difference was significant in all age groups in the stage IA group but fluctuated with age in the stage IB and IIA groups.

Skin melanoma survival is not superior in females in the new stage IIID of the 8th edition of the staging system: an analysis of data from the Surveillance, Epidemiology, and End Results (SEER) database

Background

In the 8th edition of the melanoma staging system, stage III was divided into stages IIIA-IIID. Previous studies have found that the long-term survival rate of females is much higher than that of males. This study was designed to explore whether this sex-specific advantage still exists in the new staging subgroups.

Methods

We obtained data from individuals diagnosed with skin melanoma between 2004 and 2015 from the Surveillance, Epidemiology, and End Results (SEER) database. A total of 8,726 patients with stage III disease were enrolled in the study (5,370 males and 3,356 females). Among these patients, 505 had stage IIID disease (370 males and 135 females).

Results

In the 7th edition of the staging system, there were significant sex-specific differences in overall survival (OS) and melanoma-specific survival (MSS) in each subgroup of stage III. In stages IIIA-IIIC in the 8th edition, there were also significant differences between males and females (P<0.001), but in stage IIID patients, there were no significant differences in either OS (P=0.312) or MSS (P=0.288). Cox analysis confirmed that stage IIID does not affect prognosis in males. Further research found no difference between males and females with stage IIID disease in any age subgroup.

Conclusions

We compared sex-specific survival differences in patients with stage III disease according to the 8th edition of the staging system. Females with stage IIIA-IIIC disease have better survival rates than males. However, among patients with stage IIID disease, there is no significant difference in survival between males and females.

Sex and Gender Disparities in Melanoma

Worldwide, the total incidence of cutaneous melanoma is higher in men than in women, with some differences related to ethnicity and age and, above all, sex and gender. Differences exist in respect to the anatomic localization of melanoma, in that it is more frequent on the trunk in men and on the lower limbs in women. A debated issue is if-and to what extent-melanoma development can be attributed to gender-specific behaviors or to biologically intrinsic differences. In the search for factors responsible for the divergences, a pivotal role of sex hormones has been observed, although conflicting results indicate the involvement of other mechanisms. The presence on the X chromosome of numerous miRNAs and coding genes playing immunological roles represents another important factor, whose relevance can be even increased by the incomplete X chromosome random inactivation. Considering the known advantages of the female immune system, a different cancer immune surveillance efficacy was suggested to explain some sex disparities. Indeed, the complexity of this picture emerged when the recently developed immunotherapies unexpectedly showed better improvements in men than in women. Altogether, these data support the necessity of further studies, which consider enrolling a balanced number of men and women in clinical trials to better understand the differences and obtain actual gender-equitable healthcare.