Malignant Melanoma in Pigmented Skin: Does the Current Interventional Model Fit a Different Clinical, Histologic, and Molecular Entity?

Melanoma in skin of color: Part I. Epidemiology and clinical presentation

Although there is a higher incidence of melanoma among non-Hispanic White individuals, melanoma is diagnosed at more advanced stages and associated with worse survival rates among individuals with skin of color (SOC). The proportions of melanoma subtypes differ across racial groups, with acral lentiginous melanoma and mucosal melanoma representing higher proportions of melanoma diagnoses in individuals with SOC compared to White individuals. The recognition of distinct differences in anatomic locations and dermatoscopic patterns may facilitate the appropriate differentiation of physiologic from pathologic pigmentation. The first article of this continuing medical education series will focus on the epidemiology and clinical presentation of melanoma in individuals with SOC, with the aim of improving early diagnoses and clinical outcomes.

Utilization and impact of immunotherapy in stage IV melanoma using the National Cancer Database

To evaluate factors affecting the utilization of immunotherapy and to stratify results based on the approval of ipilimumab in 2011 and PD-1 inhibitors in 2014, an analysis of available data from the National Cancer Database (NCDB) was performed. Stage IV melanoma patients were identified. Effects of immunotherapy on overall survival (OS) were assessed using Kaplan-Meier curves and Cox proportional hazards model. A total of 19 233 patients were analyzed and 1998 received immunotherapy. Between 2011 and 2013, and in 2014, 18.6 and 28.9% of patients received immunotherapy, respectively. Patients who received immunotherapy from 2011 to 2013 had a 33% (95% CI, 30-35%) 3-year OS compared to 23% (95% CI, 21-24%). In 2014, 3-year OS was 37% (95% CI, 32-43%) for those who received immunotherapy compared to 22% (95% CI, 18-26%) for those who did not (P < 0.0001). This is the first analysis of a large cancer database for melanoma patients with stratification based on utilization and availability of immunotherapy. Immunotherapy increased yearly and improved OS. With combination immunotherapy now more widely employed, it is expected these results will continue to improve. This is the first analysis of a large cancer database for melanoma patients with stratification based on utilization and availability of immunotherapy demonstrating that immunotherapy increased yearly and improved OS.

Clinical Presentations of Melanoma in African Americans, Hispanics, and Asians

BACKGROUND

Skin cancer has traditionally been studied in Caucasian skin. Although it does occur with increased relative frequency in Caucasians, patients with skin of color suffer from elevated morbidity and mortality when diagnosed with skin cancer.

OBJECTIVE

To detail the unique demographic, clinical, and genetic features of melanoma in patients with skin of color, including Hispanic, African American, and Asian patients.

MATERIALS AND METHODS

A PubMed search was conducted spanning dates 1947 to June 2017. A total of 246 articles were screened, from which 69 were included in this review.

RESULTS

Relative to Caucasians, melanoma has unique demographic, clinical, and genetic features in African Americans, Hispanics, and Asians that include gender and subtype predominance.

CONCLUSION

Familiarization with these unique presentations of skin cancer in skin of color is imperative to accurate identification and treatment of cutaneous malignancies in these populations and ultimately to improved disease-related outcomes.

Photothermal effect by 808-nm laser irradiation of melanin: a proof-of-concept study of photothermal therapy using B16-F10 melanotic melanoma growing in BALB/c mice

The photothermal effect is undergoing great interest due to advances in new photosensitizing materials and better-suited light sources, but studies are frequently hampered by the need to employ exogenous photothermal agents and expensive irradiation devices. Here we present a simple strategy based on direct NIR irradiation of the melanin pigment with a commercial 808-nm laser pointer. Proof-of-concept studies showed efficient photothermal effects on melanin in vitro and in vivo. After NIR irradiation, BALB/c mice bearing B16-F10 melanotic melanoma tumors revealed severe histopathological damage and massive necrosis in melanin-containing tumor tissue, while surrounding healthy tissues showed no damage. Therefore, the feasibility of this approach may allow implementing direct procedures for photothermal therapy of pigmented tumors.

Race-, Age-, and Anatomic Site-Specific Gender Differences in Cutaneous Melanoma Suggest Differential Mechanisms of Early- and Late-Onset Melanoma

In order to explore melanoma risk factors through gender-, age-, race-, and site-specific incidence rates, malignant melanoma cases from the Caucasian whites and non-whites were retrieved from the US SEER database. Age-standardized, age-, and site-specific tumor rates were calculated. All races and both genders showed positive annual average percentage changes (AAPCs) over the years, but AAPCs varied at different body sites, with men's trunk exhibiting the fastest increase. Non-whites were diagnosed at a significantly younger age than whites and showed a trend towards fewer gender differences in the age of diagnosis. However, non-whites and whites showed a similar pattern of age-specific gender differences in the incidence rate ratios. A consistent spiked difference (female vs. male, incidence rate ratio (IRR) >2) was observed at or near the age of 20⁻24 in all race groups and at all body sites. The highest female vs. male IRR was found in the hip and lower extremities, and the lowest IRR was found in the head and neck region in all races. These race-, gender-, and site-dependent differences suggest that age-associated cumulative sun exposure weighs significantly more in late-onset melanomas, while genetics and/or pathophysiological factors make important contributions to early-onset melanomas.

Skin cancer risk assessment in dark skinned immigrants: the role of social determinants and ethnicity

OBJECTIVES

Dark-skinned people have a lower incidence rate of skin cancer, in particular melanoma, which is detected at more advanced stages leading to poorer prognoses and long-term outcomes compared to whites. The gap in survival is due to some difficulty in melanoma detection, lack of attention from doctors and awareness by patients. This study aims to assess skin cancer risk awareness in dark-skinned immigrants and to determine the influence of socioeconomic factors and ethnic origin on behaviors.

DESIGN

This is a cross-sectional health facility based study carried out in a 12-month period. A semi-structured questionnaire to assess skin cancer risk awareness and a dermatological examination was offered to dark-skinned immigrants consecutively attending the dermatology department of the National Institute for Health, Migration and Poverty in Rome.

RESULTS

147 dark-skinned immigrants were enrolled, of which 54.4% were males, coming from Africa (53.1%). They were mainly young, aged 18-34 (56.5%). The level of education and length of stay in Italy was significantly related to the awareness about skin cancer: people with a high educational level (OR: 8.1 95% CI: 3.2-23.4) or immigrated more than 4 years before the interview (OR: 2.1 95% CI: 1.0-4.4) have a greater knowledge about skin cancer.

CONCLUSIONS

Education level is the strongest predictive factor of skin cancer awareness, whereas cultural behaviours and personal experience of sunburns are the main factors determining sunlight avoidance. Health promotion programs targeting immigrants must consider cultural differences related to ethnicity and country of origin, and adopt a transcultural approach.

Truncating mutations of TP53AIP1 gene predispose to cutaneous melanoma

Genetic predisposition to cutaneous malignant melanoma (CMM) involves highly penetrant predisposing genes and low and intermediate penetrant predisposing alleles. However, the missing heritability in (CMM) is still high. For such and in order to identify new genetic factors for CMM, we conducted an exome sequencing study in high-risk CMM patients. Two rounds of exome sequencing were successively performed in 33 and 27 high-risk patients. We focused on genes carrying rare nonsense, frameshift, and splice variants (allelic frequency <1%) that were present in both series of exomes. An extension study was then conducted in a large cohort (1 079 CMM patients and 1 230 Caucasian ethnically matched healthy controls), and the inactivating variants frequency was compared between groups using two-sided Fisher exact test. Two TP53AIP1 truncating mutations were identified in four patients: a frameshift c.63_64insG, p.Q22Afs*81 in two patients from the same family and in the proband of a second family; and a nonsense mutation c.95 C > A, p.Ser32Stop in a patient with multiple CMMs. In all patients, TP53AIP1 truncating variants were strongly associated with CMM risk (two-sided Fisher exact test = 0.004, OR = 3.3[1.3-8.5]). Additionally, we showed that TP53AIP1 mRNA was strongly down-regulated throughout different phases of melanoma progression. TP53AIP1 gene is a TP53 target which plays a key role by inducting apoptosis in response to UV-induced DNA damage. Constitutional mutations of TP53AIP1 had previously been involved in susceptibility to prostate cancer. Our results show that constitutional truncating TP53AIP1 mutations predispose to CMM in the French population. Replication studies in other populations should be performed.