Tumor Doubling Time in Skin Cancer: Can It Be Estimated and Is it Useful?

Skin cancer, like other cancers, is characterized by the uncontrolled growth of transformed cells. Tumor growth has been studied for decades. We review different methods for measuring skin tumor growth and propose a new system for estimating tumor doubling time that could be useful in the management of skin cancer.

Clinical Relevance of Cherry Angiomas

Cherry angiomas are the most common vascular tumors of the skin. They are particularly prevalent in the general population and become more common with age. Although an association with cancer was suggested at the end of the 19th century, when these tumors were first described, it could not be demonstrated. For many decades, therefore, cherry angiomas were considered to have no clinical relevance other than their association with age. A number of studies in recent years, however, have shown a link between cherry angiomas and exposure to various toxic substances and medications, benign and malignant diseases, and immunosuppression, rekindling interest in these lesions and providing clues for a better understanding of their etiology, pathophysiology, and clinical relevance.

Obstructive sleep apnoea is related to melanoma aggressiveness through paraspeckle protein-1 upregulation

BACKGROUND

In patients with obstructive sleep apnoea (OSA), intermittent hypoxia induces overexpression of paraspeckle component (PSPC)1, a master modulator of transforming growth factor (TGF)-β signalling, which promotes cell cancer progression through epithelial-mesenchymal transition (EMT) and acquisition of cancer stem cell (CSC)-like features. However, the persistence of intermittent hypoxia-induced effects on PSPC1, and their consequences in cancer patients are not known. To this effect, circulating PSPC1 levels were compared in patients with cutaneous melanoma with or without OSA, and their relationship with tumour aggressiveness along with the in vitro effects of soluble PSPC1 and intermittent hypoxia on melanoma cell aggressiveness mechanisms were assessed.

METHODS

In 292 cutaneous melanoma patients, sleep studies and serum levels of PSPC1 and TGF-β were evaluated. The effect of PSPC1 on expression of EMT and CSC transcription factors was assessed using melanoma cell lines with patient sera under both normoxia and intermittent hypoxia conditions.

RESULTS

PSPC1 levels were higher in patients with moderate-severe OSA compared with mild OSA or non-OSA patients. Serum levels of PSPC1 were associated with several cutaneous melanoma clinical aggressiveness indicators. Both intermittent hypoxia exposures and serum from OSA patients upregulated TGF-β expression and amplified the expression of transcription factors associated with EMT activation and acquisition of CSC characteristics.

CONCLUSION

In cutaneous melanoma patients, OSA severity is associated with higher PSPC1 serum levels, which jointly with intermittent hypoxia would enhance the self-reprogramming capabilities of EMT and CSC feature acquisition of melanoma cells, promoting their intrinsic aggressiveness.

The association between the morphology of vessels in primary cutaneous melanoma on dermoscopy, with the Breslow index, the presence of ulceration, and the dermoscopic signs of extensive regression

BACKGROUND Dermoscopy is a noninvasive technique for the diagnosis of cutaneous melanoma that may play a role in the preoperative assessment of melanoma thickness. With this technique, several vascular morphologies have been identified. The objectives of this study are to study the presence and morphology of blood vessels in a series of primary melanomas and to investigate whether they are related to the Breslow index, the presence of ulceration, and extensive dermoscopic regression. METHODS This cross-sectional study included non-acral, non-facial primary melanomas, with dermoscopic images from four hospitals in Spain. The outcome variables were: the Breslow index, the presence of dermoscopic ulceration, and an extensive dermoscopic regression. The explicative variables were: the presence of vessels, the predominant vessel in the most raised area of the melanoma, and the presence of polymorphous vessels. To study the association between qualitative variables and the Breslow index we used the Kruskal-Wallis test or Mann-Whitney U test, and between qualitative variables, the Chi-square test. To study the magnitude of the association, the ORs (95% CI) were calculated. RESULTS A set of 516 images from melanomas was collected. The presence of vessels was associated with thicker melanomas (p<0.001). Vessel type was associated with different Breslow indexes (p<0.001) (arborizing, linear irregular, corkscrew, glomerular, hairpin, and dotted vessels (in decreasing order)). The polymorphous vessels were associated with thicker melanomas (p<0.001). Linear irregular vessels were associated with ulceration (OR =10.6, 95% CI (4.9-24.0), (p<0.001)) and dotted vessels with the presence of extensive dermoscopic regression (OR=2.7, 95% CI (1.4-5.2), (p=0.003)). The main limitations of this study were the high selection of cases and the difficulty in identifying vessels in pigmented melanomas by dermoscopy. CONCLUSIONS The morphology of blood vessels in cutaneous melanoma on dermoscopy is associated with the Breslow index, the presence of ulceration, and extensive dermoscopic regression.

InterMEL: An international biorepository and clinical database to uncover predictors of survival in early-stage melanoma

INTRODUCTION

We are conducting a multicenter study to identify classifiers predictive of disease-specific survival in patients with primary melanomas. Here we delineate the unique aspects, challenges, and best practices for optimizing a study of generally small-sized pigmented tumor samples including primary melanomas of at least 1.05mm from AJTCC TNM stage IIA-IIID patients. We also evaluated tissue-derived predictors of extracted nucleic acids' quality and success in downstream testing. This ongoing study will target 1,000 melanomas within the international InterMEL consortium.

METHODS

Following a pre-established protocol, participating centers ship formalin-fixed paraffin embedded (FFPE) tissue sections to Memorial Sloan Kettering Cancer Center for the centralized handling, dermatopathology review and histology-guided coextraction of RNA and DNA. Samples are distributed for evaluation of somatic mutations using next gen sequencing (NGS) with the MSK-IMPACTTM assay, methylation-profiling (Infinium MethylationEPIC arrays), and miRNA expression (Nanostring nCounter Human v3 miRNA Expression Assay).

RESULTS

Sufficient material was obtained for screening of miRNA expression in 683/685 (99%) eligible melanomas, methylation in 467 (68%), and somatic mutations in 560 (82%). In 446/685 (65%) cases, aliquots of RNA/DNA were sufficient for testing with all three platforms. Among samples evaluated by the time of this analysis, the mean NGS coverage was 249x, 59 (18.6%) samples had coverage below 100x, and 41/414 (10%) failed methylation QC due to low intensity probes or insufficient Meta-Mixed Interquartile (BMIQ)- and single sample (ss)- Noob normalizations. Six of 683 RNAs (1%) failed Nanostring QC due to the low proportion of probes above the minimum threshold. Age of the FFPE tissue blocks (p<0.001) and time elapsed from sectioning to co-extraction (p = 0.002) were associated with methylation screening failures. Melanin reduced the ability to amplify fragments of 200bp or greater (absent/lightly pigmented vs heavily pigmented, p<0.003). Conversely, heavily pigmented tumors rendered greater amounts of RNA (p<0.001), and of RNA above 200 nucleotides (p<0.001).

CONCLUSION

Our experience with many archival tissues demonstrates that with careful management of tissue processing and quality control it is possible to conduct multi-omic studies in a complex multi-institutional setting for investigations involving minute quantities of FFPE tumors, as in studies of early-stage melanoma. The study describes, for the first time, the optimal strategy for obtaining archival and limited tumor tissue, the characteristics of the nucleic acids co-extracted from a unique cell lysate, and success rate in downstream applications. In addition, our findings provide an estimate of the anticipated attrition that will guide other large multicenter research and consortia.

Landscape of mutations in early stage primary cutaneous melanoma: An InterMEL study

It is unclear why some melanomas aggressively metastasize while others remain indolent. Available studies employing multi-omic profiling of melanomas are based on large primary or metastatic tumors. We examine the genomic landscape of early-stage melanomas diagnosed prior to the modern era of immunological treatments. Untreated cases with Stage II/III cutaneous melanoma were identified from institutions throughout the United States, Australia and Spain. FFPE tumor sections were profiled for mutation, methylation and microRNAs. Preliminary results from mutation profiling and clinical pathologic correlates show the distribution of four driver mutation sub-types: 31% BRAF; 18% NRAS; 21% NF1; 26% Triple Wild Type. BRAF mutant tumors had younger age at diagnosis, more associated nevi, more tumor infiltrating lymphocytes, and fewer thick tumors although at generally more advanced stage. NF1 mutant tumors were frequent on the head/neck in older patients with severe solar elastosis, thicker tumors but in earlier stages. Triple Wild Type tumors were predominantly male, frequently on the leg, with more perineural invasion. Mutations in TERT, TP53, CDKN2A and ARID2 were observed often, with TP53 mutations occurring particularly frequently in the NF1 sub-type. The InterMEL study will provide the most extensive multi-omic profiling of early-stage melanoma to date. Initial results demonstrate a nuanced understanding of the mutational and clinicopathological landscape of these early-stage tumors.

A single-center comparison of our initial experiences in treating penile and urethral cancer with video-endoscopic inguinal lymphadenectomy (VEIL) and later experiences in melanoma cases

Background

Video-endoscopic inguinal lymphadenectomy (VEIL) is a minimally invasive approach that is increasingly indicated in oncological settings, with mounting evidence for its long-term oncological safety.

Objectives

To present our single-center experience of treating penile and urethral cancer with VEIL, as well as its more recent application in melanoma patients.

Methods

We prospectively recorded our experiences with VEIL from September 2010 to July 2018, registering the patient primary indication, surgical details, complications, and follow-up.

Results

Twenty-nine patients were operated in one (24) or both (5) groins; 18 had penile cancer, 1 had urethral cancer, and 10 had melanoma. A mean 8.62 ± 4.45 lymph nodes were removed using VEIL and of these, an average of 1.00 ± 2.87 were metastatic; 16 patients developed lymphocele and 10 presented some degree of lymphedema; there were no skin or other major complications. The median follow-up was 19.35 months; there were 3 penile cancer patient recurrences in the VEIL-operated side. None of the melanoma patients presented a lymphatic inguinal recurrence.

Conclusions

VEIL is a minimally invasive technique which appears to be oncologically safe showing fewer complications than open surgery. However, complications such as lymphorrhea, lymphocele, or lymphedema were not diminished by using VEIL.

Practical Considerations About Optimal Skin Incisions/Excisions in Dermatologic Surgery with Emphasis on Incisions Orientation and Primary Cutaneous Melanoma Surgery

Dermatologic surgery has 2main objectives: 1) to guarantee surgical radicality; and 2) to achieve optimal aesthetic and functional results. These 2paradigms and their hierarchy must be considered when performing surgical procedures on the skin. Even the easiest intervention, the elliptical excision, presents some features that should be known to achieve such goals. One of these features is the incision orientation. The optimal incisions orientation is still matter of debate, especially because studies that compare the outcomes of performing incisions in different directions are lacking. However, some anatomical, clinical, and histological observations may point out why incising the skin in one orientation is better than another. Knowing the theory behind skin incisions/excisions become of outmost importance when dealing with primary cutaneous melanoma surgery. Especially if the melanocytic lesion is suspected to be an invasive melanoma and a sentinel lymph node biopsy will be required.

Self-Assessment Questionnaire on Patient-Physician Concordance on Nevus Self-Count and Models Development to Predict High-Risk Phenotype >50 Nevi

BACKGROUND

Cutaneous melanoma accounts for the majority of skin cancer-related deaths. Readily identifiable phenotypic characteristics and total body nevus count (TBNC) >50 are among the most important risk factors for cutaneous melanoma. Implementation of nevus self-count procedures and self-assessment of phenotypic traits as part of skin self-examination could be an excellent screening tool for identifying an at-risk target population.

OBJECTIVES

Objectives of the study were to assess the skills of a central Italian and eastern Spanish population sample to recognize their skin lesions via the submission of a self-assessment questionnaire and to explore which self-assessment questionnaire item combination best predicts the high-risk condition of TBNC >50.

METHODS

Patients aged ≥18 years filled a self-assessment questionnaire, autonomously and prior to the dermatological visit. Subsequently, dermatologists performed total body skin examination and reported patients' skin lesions on a separate questionnaire.

RESULTS

We reported fair to moderate patient-dermatologist agreement for skin lesion self-assessment. The item number of nevi on the back was the single questionnaire item most accurately predicting TBNC >50. The high-sensitivity and high-specificity classification and regression tree models for the prediction of TBNC >50 displayed different items combinations; the item nevus on the back was always the first and most important predictor in both our models.

CONCLUSIONS

Patients were partially able to provide correct estimation of their whole-body nevus self-count. The item nevi on the back seems to be the first and most important predictor of TBNC >50 across our models. Delivery of high-sensitivity and high-specificity prediction models based on our questionnaire item combination may help defining a high-risk target population.

Prognostic Value of Vitamin D Serum Levels in Cutaneous Melanoma

INTRODUCTION

Vitamin D plays a fundamental role in many metabolic pathways, including those involved in cell proliferation and the immune response. Serum levels of this vitamin have been linked to melanoma risk and prognosis. This study aimed to assess the prognostic value of vitamin D serum level in melanoma.

MATERIAL AND METHODS

Retrospective, observational, longitudinal, and analytical study of 286 patients with a histologic diagnosis of melanoma in whom serum levels of vitamin D were measured at the time of diagnosis. We analyzed associations between serum level and epidemiologic and clinical variables and pathology findings; we also analyzed the influence of vitamin D on overall survival. An iterative loop was used to identify a vitamin D serum level to test for its an association with survival.

RESULTS

A vitamin D level less than 9.25ng/mL was associated with a histologic finding of ulceration. After a median follow-up period of 39.4 months, 24 patients (8.4%) had died. The cutoff of 9.25ng/mL was associated with lower overall survival according to both the Kaplan-Meier curves and multivariate Cox regression analysis.

CONCLUSION

Vitamin D levels less than 9.25ng/mL are associated with ulceration in melanoma and serve as an independent prognostic factor for overall survival in this disease.

Epidemiology of Melanoma in Spain: Estimation of Number of Patients With Stage III Disease Eligible for Adjuvant Therapies

BACKGROUND AND OBJECTIVE

Accurate information on the incidence of melanoma by stage and a better understanding of transition between stages are important for determining the burden of disease and assessing the impact of new adjuvant therapies on recurrence and survival. The aim of this study was to estimate the incidence rates of the various stages of melanoma in Spain and to estimate the number of patients with stage III disease who are eligible for adjuvant systemic therapies.

MATERIALS AND METHOD

We built an epidemiological model using prospectively collected data from patients diagnosed with de novo or recurrent melanoma between 2012 and 2016 in the melanoma units of 4 public hospitals.

RESULTS

The estimated crude incidence rates for stage I and II melanoma were 7 and 2.9 cases per 100,000 person-years, respectively. The corresponding rates for stage III and IV melanoma were 1.9 and 1.3 cases per 100,000 person-years; 25.8% of patients with stage III melanoma were stage IIIA, 47% were stage IIIB, and 27.3% were stage IIIC. The respective estimated incidence rates for recurrent stage III and IV melanoma were 1.1 and 0.9 cases per 100,000 person-years. Overall, 54% of patients with recurrent stage III melanoma had progressed from stage I or II; the other cases corresponded to changes in substage. Of the patients with stage III melanoma, 85% of those with a de novo diagnosis and 80% of those who had relapsed had resectable disease, meaning they were eligible for adjuvant therapy; 47% of these patients had a BRAF mutation.

CONCLUSIONS

The above estimates could have a major impact on health care resource planning. Assessing the number of patients with melanoma who are eligible for adjuvant therapies in melanoma could help decision-makers and clinicians anticipate future needs for the management of this disease.

Subungual Melanocytic Lesions in Pediatric Patients

The study of subungual melanocytic lesions can present challenges because of the clinical and histologic characteristics of the nail unit and the difficulty of performing nail biopsies and processing specimens. These lesions can be even more challenging in children due to differences in clinical and epidemiological profiles between the adult and pediatric populations. Many of the clinical features of subungual melanocytic lesions that would raise alarm in an adult do not have the same implications in children. Consensus is also lacking on when a nail biopsy is needed to rule out malignancy in the pediatric setting. In view of these considerations and the rarity of subungual melanoma in childhood, the recommended approach in most cases is a watch-and-wait strategy. Subungual melanocytic lesions in children may also show atypical histopathologic features that are not necessarily associated with aggressive behavior. Subungual melanoma is very rare in childhood, with just 21 cases described to date. None of the patients developed visceral metastasis or died as a result and the diagnosis was controversial in many of the cases. Considering the above and the significantly higher frequency and particular characteristics of longitudinal melanonychia with a benign etiology in children, subungual melanocytic lesions should be managed differently in this setting than in adults. In most cases, a watch-and-wait approach is the most appropriate strategy.

Differences by Anatomical Site of Non-Acral Lentiginous Melanomas of the Lower Limb

BACKGROUND

Acral location of melanomas is associated with poor survival. It can be due, at least in part, to the fact that acral lentiginous melanoma, a distinct melanoma subtype, has a particular biological profile and a bad clinical behavior. However, since almost 50% of acral melanomas are not of acral lentiginous melanoma subtype, the worse clinical behavior could also be attributable to the intrinsic characteristics of the location.

OBJECTIVE

This study aimed to investigate if melanomas of the lower limb excluding acral lentiginous melanoma differ by location.

METHODS

This retrospective, observational study recruited patients from an oncology referral center in Spain. We included 285 patients with superficial spreading and nodular melanomas of the lower limb. We compare melanomas by site, clinical and pathological characteristics, and the differences by location of disease-free and melanoma-specific survival by the Kaplan-Meier method and Cox proportional hazard method.

RESULTS

Patients with melanomas on the foot, compared to those on the rest of the limb, were older and reported having suffered less sunburns; the melanoma more frequently appeared in areas that had been rarely sun exposed, were more frequently of nodular type, presented thicker tumors, with more ulceration, less regression, and more advanced stage of the disease. Foot location increased the risk of relapse and decreased melanoma-specific survival.

CONCLUSION

Melanoma development in foot is less related to sun exposure and is associated with pathological features that can account for the worse prognosis and poorer survival.

Molecular characterization of fast-growing melanomas

BACKGROUND

The rate of growth of primary melanoma is a robust predictor of aggressiveness, but the mutational profile of fast-growing melanomas (FGMM) and the potential to stratify patients at high risk of death has not been comprehensively studied.

OBJECTIVE

To investigate the epidemiologic, clinical, and mutational profile of primary cutaneous melanomas with a thickness ≥ 1 mm, stratified by rate of growth.

METHODS

Observational prospective study. Deep-targeted sequencing of 40 melanoma driver genes on formalin fixed, paraffin-embedded primary melanoma samples. Comparison of FGMM (rate of growth > 0.5 mm/month) and nonFGMM (rate of growth ≤ 0.5 mm/month).

RESULTS

Two hundred patients were enrolled, among wom 70 had FGMM. The relapse-free survival was lower in the FGMM group (P = .014). FGMM had a higher number of predicted deleterious mutations within the 40 genes than nonFGMM (P = .033). Ulceration (P = .032), thickness (P = .006), lower sun exposure (P = .049), and fibroblast growth factor receptor 2 (FGFR2) mutations (P = .037) were significantly associated with fast growth.

LIMITATIONS

Single-center study, cohort size, potential memory bias, number of investigated genes.

CONCLUSION

Fast growth is linked to specific tumor biology and environmental factors. Ulceration, thickness, and FGFR2 mutations are associated with fast growth. Screening for FGFR2 mutations might provide an additional tool to better identify FGMM, which are probably good candidates for adjuvant therapies.

Determination of Margins for Tumor Clearance in Dermatofibrosarcoma Protuberans: A Single-Center Study of 222 Cases Treated With Modified Mohs Surgery

BACKGROUND

Dermatofibrosarcoma protuberans (DFSP) is an invasive skin tumor traditionally associated with very high recurrence rates when treated with conventional surgery (CS).

OBJECTIVE

To calculate the minimum margin that would have been required to achieve complete tumor clearance with hypothetical CS. To analyze DFSP characteristics and Mohs micrographic surgery (MMS) effectiveness in treatment of this tumor.

MATERIALS AND METHODS

Minimum margin was calculated by measuring the largest distance from the visible edge of the tumor to the edge of the surgical defect. Tumor variables (age, sex, size, time since onset, and location) were correlated with surgical variables (number of stages and minimum margin).

RESULTS

We studied 222 cases of DFSP treated with MMS. A mean of 1.47 MMS stages and a mean minimum margin of 1.23 cm were required to achieve tumor clearance. Tumors on the head and neck required significantly more stages and a significantly wider margin. Tumor size was positively correlated with time to diagnosis, age, and number of MMS stages.

CONCLUSION

Tumors located on the head and neck have greater subclinical extension. Tumor size was also a predictor of surgical difficulty, but time to diagnosis was not.

Sentinel Lymph Node Biopsy vs. Observation in Thin Melanoma: A Multicenter Propensity Score Matching Study

The therapeutic value of sentinel lymph node biopsy (SLNB) in thin melanoma remains controversial. The aim of this study is to determine the role of SLNB in the survival of thin melanomas (≤1 mm). A multicenter retrospective observational study was designed. A propensity score matching was performed to compare patients who underwent SLNB vs. observation. A multivariate Cox regression was used. A total of 1438 patients were matched by propensity score. There were no significant differences in melanoma-specific survival (MSS) between the SLNB and observation groups. Predictors of MSS in the multivariate model were age, tumor thickness, ulceration, and interferon treatment. Results were similar for disease-free survival and overall survival. The 5- and 10-year MSS rates for SLN-negative and -positive patients were 98.5% vs. 77.3% (p < 0.001) and 97.3% vs. 68.7% (p < 0.001), respectively. SLNB does not improve MSS in patients with thin melanoma. It also had no impact on DSF or OS. However, a considerable difference in MSS, DFS, and OS between SLN-positive and -negative patients exists, confirming its value as a prognostic procedure and therefore we recommend discussing the option of SLNB with patients.

Distribution and clinical role of KIT gene mutations in melanoma according to subtype: a study of 492 Spanish patients

BACKGROUND

KIT mutations are primarily associated with acral and mucosal melanoma, and have been reported to show higher prevalence in chronic sun-damaged (CSD) than non-CSD melanomas.

OBJECTIVES

To investigate the prevalence of KIT mutations in melanoma according to subtype, and determine the clinical role of such mutations.

MATERIALS & METHODS

We present results from a study of a Spanish population of 492 melanomas, classified according to the latest World Health Organization (WHO) guidelines. We analysed the mutational status of KIT and correlated with different clinical variables related to sun exposure and family history.

RESULTS

KIT mutations were significantly more frequent in acral (3/36; 8.3%) and mucosal (4/8; 50%) melanomas than non-acral cutaneous melanomas. No significant difference was observed in KIT mutational status between CSD and non-CSD melanomas.

CONCLUSION

Our results suggest that KIT mutations in melanoma tumours are unrelated to the development of nevi or chronic sun damage, but their presence is associated with aggressive melanomas which show ulceration, vascular invasiveness, and increased Breslow thickness. These findings are consistent with those reported by The Cancer Genome Atlas network.

Vitamin D and Skin Cancer: An Epidemiological, Patient-Centered Update and Review

BACKGROUND

The current vitamin D deficiency epidemic is accompanied by an increase in endemic skin cancer. There are still multiple controversies. This review aims to give practical recommendations regarding vitamin D among people at risk or with a personal history of skin cancer.

METHODS

Narrative review including human research articles published between 2011 and 2021, elaborated bearing in mind an epidemiological, patient-centered approach.

RESULTS

Ultraviolet (UV) exposure (neither artificial nor natural) is not the ideal source to synthesize vitamin D. There is conflicting epidemiological evidence regarding vitamin D, non-melanoma skin cancer (NMSC), and cutaneous melanoma (CMM), confounded by the effect of sun exposure and other factors.

CONCLUSIONS

Current evidence is controversial, and there are no widely applicable strategies. We propose three practical recommendations. Firstly, sun protection recommendations should be kept among people at risk or with a personal history of skin cancer. Secondly, vitamin D should preferably be sourced through diet. In patients with melanoma or at risk of cutaneous cancer, serum vitamin D checks are warranted to detect and avoid its insufficiency.