Clinicopathologic, misdiagnosis, and survival differences between clinically amelanotic melanomas and pigmented melanomas.

BACKGROUND: Amelanotic malignant melanoma (AMM) is challenging to diagnose. Clinical risk factors for AMM are not well defined. OBJECTIVE: To investigate clinicopathologic, misdiagnosis, and survival differences between patients with AMM and those with pigmented malignant melanoma (PMM). METHODS: A cross-sectional retrospective medical record review at a tertiary academic medical center. RESULTS: A total of 933 patients with melanoma with known presenting tumor color were identified (342 with AMM vs 591 with PMM). AMM was associated with older age, history of nonmelanoma skin cancer, and red hair, whereas AMM was inversely associated with a family history of melanoma, more than 50 nevi, and a history of dysplastic nevi. Compared with PMM, AMM was more likely to be located on the head and/or neck, had more aggressive pathologic features (greater Breslow depth and/or mitoses, ulceration, nodular subtype), and was less likely to be associated with a precursor nevus or regression. Finally, patients with AMM were more likely to be misdiagnosed than were patients with PMM (25% vs 12% clinically and 12% vs 7% pathologically), and they had poorer melanoma-specific survival (5-year overall survival rate, 0.77 [95% confidence interval, 0.72-0.82] vs 0.84 [95% confidence interval, 0.80-0.87]). LIMITATIONS: Retrospective study design, single-institutional study. CONCLUSION: Greater clinician awareness, lower biopsy thresholds, and increased patient education may be useful to enhance AMM detection in patients with certain characteristics.

A pink enlarging plaque on the plantar foot: amelanotic acral lentiginous melanoma.

Acral lentiginous melanomas account for less than 5% of all melanomas, whereas amelanotic melanomas account for around 2-8% of all melanomas. Amelanotic acral lentiginous melanomas are even less common and can often be mistaken for other clinical entities, including pyogenic granulomas, non-melanoma skin cancers, and warts. We describe a man in his 50s with a twenty-year history of a skin-colored plaque on the right plantar foot; after enlargement and failure of wart treatment, a shave biopsy revealed an amelanotic melanoma. A subsequent wide local excision and sentinel lymph node biopsy revealed melanoma in 4 lymph nodes and the patient underwent an abbreviated course of interferon-alpha therapy. The patient remained stable until 2 ? years after diagnosis, at which time he presented with in-transit metastases on the foot and right thigh; he has since been stable on nivolumab. This case represents the challenge of diagnosing amelanotic melanomas on acral surfaces and highlights the importance of considering a skin biopsy for diagnosis of any changing, atypical amelanotic lesions on the feet or hands.

Monoglobus pectinilyticus gen. nov., sp. nov., a pectinolytic bacterium isolated from human faeces.

A novel anaerobic pectinolytic bacterium (strain 14T) was isolated from human faeces. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain 14T belonged to the family Ruminococcaceae, but was located separately from known clostridial clusters within the taxon. The closest cultured relative of strain 14T was Acetivibrio cellulolyticus (89.7 % sequence similarity). Strain 14T shared ~99 % sequence similarity with cloned 16S rRNA gene sequences from uncultured bacteria derived from the human gut. Cells were Gram-stain-positive, non-motile cocci approximately 0.6 µm in diameter. Strain 14T fermented pectins from citrus peel, apple, and kiwifruit as well as carbohydrates that are constituents of pectins and hemicellulose, such as galacturonic acid, xylose, and arabinose. TEM images of strain 14T, cultured in association with plant tissues, suggested extracellular fibrolytic activity associated with the bacterial cells, forming zones of degradation in the pectin-rich regions of middle lamella. Phylogenetic and phenotypic analysis supported the differentiation of strain 14T as a novel genus in the family Ruminococcaceae. The name Monoglobus pectinilyticus gen. nov., sp. nov. is proposed; the type strain is 14T (JCM 31914T=DSM 104782T).

An incomplete picture: challenges of partial biopsies in large diameter atypical melanocytic lesions.

Large diameter atypical pigmented lesions (LDAPL) can be challenging to diagnose accurately using partial biopsies because of pathologic heterogeneity, while at the same time large excisions of these lesions confer significant morbidity to patients. Consequently, clinicians are often challenged by the management of these lesions. In this case, we describe an elderly patient with a history of multiple basal cell carcinomas, prior melanomas, and a family history of melanoma who presented with an irregularly pigmented brown and dark brown patch on his upper back. This lesion was evaluated with multiple partial incisional biopsies from the most atypical appearing areas of the lesion identified on dermoscopy, each showing mild and moderate atypical melanocytes. However, the patch continued to change clinically and eventually the patient underwent a 5mm wide local excision, which revealed severely atypical melanocytic proliferation with areas consistent with melanoma in situ. This case highlights the need for clinicians to lower their threshold for excisional biopsy of LDAPL in high-risk patients.

Reduction in nevus biopsies in patients monitored by total body photography.

BACKGROUND: Total body photography (TBP) can facilitate identification of new and changing lesions. By confirming that particular nevi are stable, TBP may reduce nevus biopsies. OBJECTIVES: We sought to determine the number and rate of nevus biopsies before and after TBP, and the factors associated with increased biopsy rate during monitoring by TBP. METHODS: We reviewed records of all patients in 2 pigmented lesion clinics (PLCs) who received TBP and had 2 or more follow-up visits over a period of 2 years or longer. RESULTS: Before PLCs and TBP, the mean number of nevus biopsies per patient was 5.92 (589 patients) at a mean rate of 1.62 per year (160 patients). After TBP in PLCs, the same patients averaged 1.56 biopsies at a mean rate of 0.34 per year (P < 2 × 10(-16)). The entire cohort (926 patients) averaged similarly low post-TBP biopsy rates of less than 0.2 per year and per visit. Biopsy rates after TBP were positively correlated with decreased age, male gender, and family history of melanoma, but not nevus number. LIMITATIONS: Some information was not available for some patients. CONCLUSIONS: Patients at risk for melanoma experienced a 3.8-fold reduction in nevus biopsies after TBP. Younger male patients with family history of melanoma had higher biopsy rates after TBP.

Widely metastatic squamous cell carcinoma originating from malignant transformation of hypertrophic lichen planus in a 24-year-old woman: case report and review of the literature.

Hypertrophic lichen planus (HLP) is a T-cell-mediated process typically presenting with hypertrophic or verrucous plaques on the lower limbs. We report the case of a 24-year-old woman with a history of HLP since age 3 years presenting with rapid malignant transformation of one lesion into a large squamous cell carcinoma (SCC). Subsequent examination revealed progressive, widespread metastatic involvement, and the patient ultimately died from her disease. SCC associated with HLP is rare, with a review of the literature revealing fewer than 50 cases. This case highlights the need to be aware of suspicious changes in HLP and to educate patients as to when to be reevaluated.

Analysis of dermatologic events in vemurafenib-treated patients with melanoma.

BACKGROUND: Vemurafenib has been approved for the treatment of patients with advanced BRAF(V600E)-mutant melanoma. This report by the Vemurafenib Dermatology Working Group presents the characteristics of dermatologic adverse events (AEs) that occur in vemurafenib-treated patients, including cutaneous squamous cell carcinoma (cuSCC). METHODS: Dermatologic AEs were assessed from three ongoing trials of BRAF(V600E) mutation-positive advanced melanoma. Histologic central review and genetic characterization were completed for a subset of cuSCC lesions. RESULTS: A total of 520 patients received vemurafenib. The most commonly reported AEs were dermatologic AEs, occurring in 92%-95% of patients. Rash was the most common AE (64%-75% of patients), and the most common types were rash not otherwise specified, erythema, maculopapular rash, and folliculitis. Rash development did not appear to correlate with tumor response. Photosensitivity occurred in 35%-63% of patients, and palmar-plantar erythrodysesthesia (PPE) occurred in 8%-10% of patients. The severity of rash, photosensitivity, and PPE were mainly grade 1 or 2. In all, 19%-26% of patients developed cuSCC, mostly keratoacanthomas (KAs). The majority of patients with cuSCC continued therapy without dose reduction after resection. Genetic analysis of 29 cuSCC/KA samples demonstrated HRAS mutations in 41%. CONCLUSIONS: Dermatologic AEs associated with vemurafenib treatment in patients with melanoma were generally manageable with supportive care measures. Dose interruptions and/or reductions were required in <10% of patients.

Prognostic gene expression profile testing to inform use of adjuvant therapy: A survey of melanoma experts.

OBJECTIVES: To investigate current practices and attitudes regarding use of adjuvant immunotherapy and prognostic gene expression profile (GEP) testing among melanoma medical and surgical oncologists. METHODS: An anonymous RedCap-based survey was emailed to ~300 melanoma experts. RESULTS: Respondents generally favored adjuvant immunotherapy over observation (73% for all Stage IIIA, 50% for Stage IIB/IIC) and cited a minimum 10-year recurrence risk of 11%-20% (48%) or 21%-30% (33%) to justify treatment, but acknowledged that risks of serious adverse events may outweigh potential benefits for some Stage IIB/IIC patients. While GEP test results did not strongly influence decision-making regarding follow-up or intervention, most were receptive to randomized trials using GEP testing to identify subsets of Stage IIB/IIC (74%) and Stage IB/IIA (54%) patients who may not or may, respectively, benefit from adjuvant therapy. CONCLUSION: Although most respondents do not routinely use GEP testing, many would participate in clinical trials to determine clinical utility.

Livedo reticularis: a side effect of interferon therapy in a pediatric patient with melanoma.

Livedo reticularis is a lacy mottling of the skin that can have many etiologies. We report a case of an 8-year-old boy with a diagnosis of melanoma who developed persistent livedo reticularis during treatment with interferon alpha-2B. To our knowledge, this is the first case report of livedo reticularis occurring as a side effect of interferon treatment for pediatric melanoma. Given the increasing incidence of pediatric melanoma, it is important that dermatologists be aware of potential side effects of interferon therapy to optimize care and education for these patients.

Using deep learning for dermatologist-level detection of suspicious pigmented skin lesions from wide-field images.

A reported 96,480 people were diagnosed with melanoma in the United States in 2019, leading to 7230 reported deaths. Early-stage identification of suspicious pigmented lesions (SPLs) in primary care settings can lead to improved melanoma prognosis and a possible 20-fold reduction in treatment cost. Despite this clinical and economic value, efficient tools for SPL detection are mostly absent. To bridge this gap, we developed an SPL analysis system for wide-field images using deep convolutional neural networks (DCNNs) and applied it to a 38,283 dermatological dataset collected from 133 patients and publicly available images. These images were obtained from a variety of consumer-grade cameras (15,244 nondermoscopy) and classified by three board-certified dermatologists. Our system achieved more than 90.3% sensitivity (95% confidence interval, 90 to 90.6) and 89.9% specificity (89.6 to 90.2%) in distinguishing SPLs from nonsuspicious lesions, skin, and complex backgrounds, avoiding the need for cumbersome individual lesion imaging. We also present a new method to extract intrapatient lesion saliency (ugly duckling criteria) on the basis of DCNN features from detected lesions. This saliency ranking was validated against three board-certified dermatologists using a set of 135 individual wide-field images from 68 dermatological patients not included in the DCNN training set, exhibiting 82.96% (67.88 to 88.26%) agreement with at least one of the top three lesions in the dermatological consensus ranking. This method could allow for rapid and accurate assessments of pigmented lesion suspiciousness within a primary care visit and could enable improved patient triaging, utilization of resources, and earlier treatment of melanoma.

Dermoscopy Proficiency Expectations for US Dermatology Resident Physicians: Results of a Modified Delphi Survey of Pigmented Lesion Experts.

Importance: Dermoscopy education in US dermatology residency programs varies widely, and there is currently no existing expert consensus identifying what is most important for resident physicians to know. Objectives: To identify consensus-based learning constructs representing an appropriate foundational proficiency in dermoscopic image interpretation for dermatology resident physicians, including dermoscopic diagnoses, associated features, and representative teaching images. Defining these foundational proficiency learning constructs will facilitate further skill development in dermoscopic image interpretation to help residents achieve clinical proficiency. Design, Setting, and Participants: A 2-phase modified Delphi surveying technique was used to identify resident learning constructs in 3 sequential sets of surveys-diagnoses, features, and images. Expert panelists were recruited through an email distributed to the 32 members of the Pigmented Lesion Subcommittee of the Melanoma Prevention Working Group. Twenty-six (81%) opted to participate. Surveys were distributed using RedCAP software. Main Outcomes and Measures: Consensus on diagnoses, associated dermoscopic features, and representative teaching images reflective of a foundational proficiency in dermoscopic image interpretation for US dermatology resident physicians. Results: Twenty-six pigmented lesion and dermoscopy specialists completed 8 rounds of surveys, with 100% (26/26) response rate in all rounds. A final list of 32 diagnoses and 116 associated dermoscopic features was generated. Three hundred seventy-eight representative teaching images reached consensus with panelists. Conclusions and Relevance: Consensus achieved in this modified Delphi process identified common dermoscopic diagnoses, associated features, and representative teaching images reflective of a foundational proficiency in dermoscopic image interpretation for dermatology residency training. This list of validated objectives provides a consensus-based foundation of key learning points in dermoscopy to help resident physicians achieve clinical proficiency in dermoscopic image interpretation.

Prognostic Gene Expression Profiling in Cutaneous Melanoma: Identifying the Knowledge Gaps and Assessing the Clinical Benefit.

Importance: Use of prognostic gene expression profile (GEP) testing in cutaneous melanoma (CM) is rising despite a lack of endorsement as standard of care. Objective: To develop guidelines within the national Melanoma Prevention Working Group (MPWG) on integration of GEP testing into the management of patients with CM, including (1) review of published data using GEP tests, (2) definition of acceptable performance criteria, (3) current recommendations for use of GEP testing in clinical practice, and (4) considerations for future studies. Evidence Review: The MPWG members and other international melanoma specialists participated in 2 online surveys and then convened a summit meeting. Published data and meeting abstracts from 2015 to 2019 were reviewed. Findings: The MPWG members are optimistic about the future use of prognostic GEP testing to improve risk stratification and enhance clinical decision-making but acknowledge that current utility is limited by test performance in patients with stage I disease. Published studies of GEP testing have not evaluated results in the context of all relevant clinicopathologic factors or as predictors of regional nodal metastasis to replace sentinel lymph node biopsy (SLNB). The performance of GEP tests has generally been reported for small groups of patients representing particular tumor stages or in aggregate form, such that stage-specific performance cannot be ascertained, and without survival outcomes compared with data from the American Joint Committee on Cancer 8th edition melanoma staging system international database. There are significant challenges to performing clinical trials incorporating GEP testing with SLNB and adjuvant therapy. The MPWG members favor conducting retrospective studies that evaluate multiple GEP testing platforms on fully annotated archived samples before embarking on costly prospective studies and recommend avoiding routine use of GEP testing to direct patient management until prospective studies support their clinical utility. Conclusions and Relevance: More evidence is needed to support using GEP testing to inform recommendations regarding SLNB, intensity of follow-up or imaging surveillance, and postoperative adjuvant therapy. The MPWG recommends further research to assess the validity and clinical applicability of existing and emerging GEP tests. Decisions on performing GEP testing and patient management based on these results should only be made in the context of discussion of testing limitations with the patient or within a multidisciplinary group.

Prognostic gene expression profiling in melanoma: necessary steps to incorporate into clinical practice.

Prognostic gene expression profiling (GEP) tests for cutaneous melanoma (CM) are not recommended in current guidelines outside of a clinical trial. However, their use is becoming more prevalent and some practitioners are using GEP tests to guide patient management. Thus, there is an urgent need to bridge this gap between test usage and clinical guideline recommendations by obtaining high-quality evidence to guide us toward best practice use of GEP testing in CM patients. We focus here on the opportunities and uncertainties associated with prognostic GEP testing in CM, review how GEP testing was incorporated into clinical care guidelines for uveal melanoma and breast cancer and discuss the role of clinical trials to determine best use in patients with CM.

Genomic insights from Monoglobus pectinilyticus: a pectin-degrading specialist bacterium in the human colon.

Pectin is abundant in modern day diets, as it comprises the middle lamellae and one-third of the dry carbohydrate weight of fruit and vegetable cell walls. Currently there is no specialized model organism for studying pectin fermentation in the human colon, as our collective understanding is informed by versatile glycan-degrading bacteria rather than by specialist pectin degraders. Here we show that the genome of Monoglobus pectinilyticus possesses a highly specialized glycobiome for pectin degradation, unique amongst Firmicutes known to be in the human gut. Its genome encodes a simple set of metabolic pathways relevant to pectin sugar utilization, and its predicted glycobiome comprises an unusual distribution of carbohydrate-active enzymes (CAZymes) with numerous extracellular methyl/acetyl esterases and pectate lyases. We predict the M. pectinilyticus degradative process is facilitated by cell-surface S-layer homology (SLH) domain-containing proteins, which proteomics analysis shows are differentially expressed in response to pectin. Some of these abundant cell surface proteins of M. pectinilyticus share unique modular organizations rarely observed in human gut bacteria, featuring pectin-specific CAZyme domains and the cell wall-anchoring SLH motifs. We observed M. pectinilyticus degrades various pectins, RG-I, and galactan to produce polysaccharide degradation products (PDPs) which are presumably shared with other inhabitants of the human gut microbiome (HGM). This strain occupies a new ecological niche for a primary degrader specialized in foraging a habitually consumed plant glycan, thereby enriching our understanding of the diverse community profile of the HGM.