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.

Association of HPV42 with digital papillary adenocarcinoma and the use of in situ hybridization for its distinction from acral hidradenoma and diagnosis at non-acral sites

Digital papillary adenocarcinoma (DPAC) is a rare tumor of sweat gland origin that preferentially affects the digits and has the potential to metastasize. Its tumor diagnosis can be difficult. Well-differentiated variants of DPAC can be confused with a benign sweat gland tumor, in particular nodular hidradenoma. With the recent detection of HPV42 DNA in DPAC by next-generation sequence analysis, we reasoned that this association could be used for diagnostic purposes. To this end, we performed in situ hybridization for HPV42 on 10 tumors diagnosed as DPAC as well as 30 sweat gland tumors of various histology types, including 8 acral hidradenomas. All DPAC were positive for HPV42. Positive hybridization signals for HPV42 were seen in both primary and metastatic DPACs. All other tumors and normal tissues were negative. This study confirms the association of HPV42 with the tumor cells of DPAC through in situ hybridization. The positive test result in all lesions of DPAC and lack of detection of HPV42 in any of the acral hidradenomas or other sweat gland tumors examined in this series is encouraging for the potential diagnostic utility of the assay. As documented by two scrotal tumors of DPAC, the in situ hybridization test for HPV42 can also help support the rare occurrence of this tumor at a non-acral site.

PRAME Expression Correlates With Genomic Aberration and Malignant Diagnosis of Spitzoid Melanocytic Neoplasms

ABSTRACT

Spitzoid melanocytic neoplasms are a diagnostically challenging class of lesions in dermatopathology. Recently, molecular assays and immunohistochemical markers have been explored as ancillary methods to assist in the diagnostic workup. Specifically, preferentially expressed antigen in melanoma (PRAME) immunohistochemistry is a nuclear stain commonly positive in melanomas, but not in nevi. This study investigates PRAME immunoreactivity (≥75% positive nuclear staining in tumor cells) in a set of 59 spitzoid melanocytic neoplasms with known clinical outcomes. We compared PRAME status with (1) the clinical outcomes, (2) the morphologic diagnoses, and (3) the status of TERT promoter mutation. Regarding clinical outcomes, 3 cases developed metastatic disease, of which 2 expressed diffusely positive PRAME staining. Of the 56 cases that did not show evidence of metastasis, 6 expressed diffusely positive PRAME staining. Morphologically, diffusely positive PRAME staining was seen in 7 of 21 cases (33.3%) diagnosed as melanoma and only 1 benign tumor 1 of 38 (2.6%). There were 4 of 8 cases with a TERT promoter mutation which were diffusely PRAME-positive compared with 4 of 51 cases without TERT promoter mutation ( P = 0.001). Our results show a statistically significant correlation between PRAME expression and the diagnosis, outcome, and TERT promoter mutation status of atypical spitzoid melanocytic neoplasms, suggesting immunohistochemistry for PRAME can help support a suspected diagnosis. However, because of occasional false-positive and negative test results, correlation with the clinical and histologic findings as well as results from other tests is needed for the interpretation of diagnostically challenging spitzoid melanocytic neoplasms.

Assessing PD-L1 without a biopsy and through PD-L1 PET imaging with 18F-BMS-986229

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Background: Programmed death ligand-1 (PD-L1) is usually determined by immunohistochemistry (IHC). Determining PD-L1 status by whole body, non-invasive PD-L1 PET imaging with 18F-BMS-986229 tracer infusion may be a way to circumvent limitations to PD-L1 IHC such as poor tissue availability; discrepant PD-L1 IHC results among different tumors within the same patient; and inability to measure PD-L1 longitudinally given challenges with repeated biopsies. Methods: Within the prospective ADAPT-IT trial (NCT03122522) testing an abbreviated course of nivolumab (nivo) + ipilimumab (ipi) in patients with unresectable stage III or IV melanoma, we investigated PD-L1 PET imaging in a 10-patient expansion cohort at baseline and after 6 weeks of treatment. Maximum standard uptake value (SUV max) and mean of all SUV max for lesions for PD-L1 PET were calculated on a whole patient level for each target/ non target lesion. Standard treatment response was determined by RECIST v1.1 at weeks 6 and 12. PD-L1 IHC was scored using the E1L3N antibody by tumor proportion score (TPS), Immune Cell Score (ICS), and a Combined Positive Score (CPS). Comparisons between PD-L1 PET parameters and response were determined by complete or partial response (CR/PR); stable disease (SD), and progressive disease (PD) at respective imaging timepoints. Absolute changes in PD-L1 SUV mean and max were calculated between scans. The correlation between PD-L1 PET and IHC was estimated using Spearman’s coefficient correlation. Results: Five patients (50%) had a PR to treatment at week 6; one of these PR became a CR at week 12 and one PR was not assessable at week 12. All RECIST responders at week 6 (n = 5) had baseline PD-L1 SUV mean ≥3.00, and all progressors at week 6 (n = 3) had baseline PD-L1 SUV mean ≤2.60 (Table). A similar trend was observed when assessing response at week 12 and when considering baseline PD-L1 SUV max. Patients had changes in their PD-L1 SUV levels between baseline and week 6. Baseline PD-L1 SUV mean (inclusive of all lesions within a patient) correlated with PD-L1 IHC by TPS, ICS, and CPS (r = 0.64, 0.5, 0.47, respectively). No patients had side effects from 18F-BMS-986229 tracer infusion. Conclusions: The signal of PD-L1 positivity by PET imaging with 18F-BMS-986229 at baseline appears associated with early efficacy from nivo + ipi in this small cohort and may offer additional information than PD-L1 IHC. The ability to assess PD-L1 on a whole patient level at multiple timepoints on treatment may have future implications in how best to sequence and combine immunotherapies but further study in larger patient cohorts is needed. Clinical trial information: NCT03122522. [Table: see text]

Defining Novel DNA Virus-Tumor Associations and Genomic Correlates Using Prospective Clinical Tumor/Normal Matched Sequencing Data

This study is the largest analysis of DNA viruses in solid tumors with associated genomics. To achieve this, a novel method for discovery of DNA viruses from matched tumor/normal next-generation sequencing samples was developed and validated. This method performed comparably to reference methods for the detection of high-risk (HR) human papilloma virus (HPV) (area under the receiver operating characteristic curve = 0.953). After virus identification in 48,148 consecutives samples from 42,846 unique patients, novel virus tumor associations were established by segregating tumor types to determine whether each DNA virus was enriched in each of the tumor types compared with the remaining cohort. All firmly established solid tumor-virus associations (eg, HR HPV in cervical cancer) were confirmed, and the novel associations discovered included: human herpes virus 6 in neuroblastoma, human herpes virus 7 in esophagogastric cancer, and HPV42 in digital papillary adenocarcinoma. These associations were confirmed in an independent validation cohort. HR HPV- and Epstein-Barr virus-associated tumors showed newly discovered genomic associations, including a lower tumor mutation burden. The study demonstrated the ability to study the role of DNA viruses in human cancer from clinical genomics data and established the largest cohort that can be utilized as a validation set for future discovery efforts.

Pancreatic cancer: Cutaneous metastases, clinical descriptors and outcomes

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Background: The occurrence of cutaneous metastasis from pancreatic cancer (PC) is rare, and the exact incidence is unknown. The literature to date is primarily limited to isolated case reports. Herein, we evaluate the clinical, genomic, and other descriptors of patients with PC and cutaneous metastases. Methods: Institutional databases were queried using search terms “pancreas cancer” and “cutaneous mets”. Clinical history, demographics, PC cutaneous metastasis details, and survival outcomes were abstracted. Results were described using descriptive statistics, and overall survival (OS) from the diagnosis of cutaneous metastasis was estimated using Kaplan-Meier methods. Results: Of 140 on initial search, 40 patients met inclusion criteria of PC and cutaneous metastases and were analyzed. The median age (Q1-Q3, IQR) of pancreatic cancer diagnosis was 66.0 (59.3-72.3, 12.9) years. Most common histologic subtype was adenocarcinoma (n= 39, 98%), and one patient had a neuroendocrine malignancy. Most patients had stage IV disease at diagnosis (n=26, 65%). The most common location of the primary tumor was tail of the pancreas (n=17, 43%). Forty-eight percent (n= 19) had cutaneous metastasis at/within one month of cancer diagnosis. Most patients received chemotherapy (n=37, 93%), with 14 patients (35%) patients also receiving local therapy in the form of local excision or radiation. The most common cutaneous metastasis site was the abdomen (n=40, 66%), with umbilical lesions occurring in 58% (n=23) of abdominal lesions. The median interval (Q1-Q3, IQR) between diagnosis of pancreatic cancer and development of cutaneous metastasis was 1.4 (0-14.5, 14.5) months. The median OS (95% CI) from cutaneous metastasis diagnosis was 11 months (7.0, 20). Table details the observed differences between umbilical vs. non-umbilical metastases. Sixteen of 40 (40%) patients underwent somatic testing. The most frequently mutated genes were KRAS (n= 16, 100%), TP53 (n=7, 44%), CDKN2Ap14ARF (n=5, 31%), CDKN2Ap16INK4A (n=5, 31%), and CDKN2B (n=3, 19%). Germline testing was undertaken in 12 (30%) patients, and pathogenic variants were observed in 3: CHEK2 (n=1, 8%), BRCA1 (n=1, 8%), and ATM (n= 1, 8%). Summary of cutaneous metastasis characteristics. Conclusions: Cutaneous metastases from PC are rare and can be present at the time of diagnosis of stage IV disease, occurring most frequently in the umbilicus. Cutaneous metastases can be classified into umbilical and non-umbilical metastases, which may be due to a different biology.[Table: see text]

Disease-Associated Risk Variants in ANRIL Are Associated with Tumor-Infiltrating Lymphocyte Presence in Primary Melanomas in the Population-Based GEM Study

BACKGROUND

Genome-wide association studies have reported that genetic variation at ANRIL (CDKN2B-AS1) is associated with risk of several chronic diseases including coronary artery disease, coronary artery calcification, myocardial infarction, and type 2 diabetes mellitus. ANRIL is located at the CDKN2A/B locus, which encodes multiple melanoma tumor suppressors. We investigated the association of these variants with melanoma prognostic characteristics.

METHODS

The Genes, Environment, and Melanoma Study enrolled 3,285 European origin participants with incident invasive primary melanoma. For each of ten disease-associated SNPs at or near ANRIL, we used linear and logistic regression modeling to estimate, respectively, the per allele mean changes in log of Breslow thickness and ORs for presence of ulceration and tumor-infiltrating lymphocytes (TIL). We also assessed effect modification by tumor NRAS/BRAF mutational status.

RESULTS

Rs518394, rs10965215, and rs564398 passed false discovery and were each associated (P ≤ 0.005) with TILs, although only rs564398 was independently associated (P = 0.0005) with TILs. Stratified by NRAS/BRAF mutational status, rs564398*A was significantly positively associated with TILs among NRAS/BRAF mutant, but not wild-type, cases. We did not find SNP associations with Breslow thickness or ulceration.

CONCLUSIONS

ANRIL rs564398 was associated with TIL presence in primary melanomas, and this association may be limited to NRAS/BRAF-mutant cases.

IMPACT

Pathways related to ANRIL variants warrant exploration in relationship to TILs in melanoma, especially given the impact of TILs on immunotherapy and survival.

Optical imaging guided- 'precision' biopsy of skin tumors: a novel approach for targeted sampling and histopathologic correlation

Dermoscopy and reflectance confocal microscopy (RCM) are two noninvasive, optical imaging tools used to facilitate clinical diagnosis. A biopsy technique that produces exact correlation with optical imaging features is not previously reported. To evaluate the applications of a novel feature-focused 'precision biopsy' technique that correlates clinical-dermoscopy-RCM findings with histopathology. This was a prospective case-series performed during August 2017 and June 2019 at a tertiary care cancer. We included consecutive patients requiring a precise dermoscopy-RCM-histopathologic correlation. We performed prebiopsy dermoscopy and both wide probe and handheld RCM of suspicious lesions. Features of interest were isolated with the aid of paper rings and a 2 mm punch biopsy was performed in the dermoscopy- or RCM-highlighted area. Tissue was processed either en face or with vertical sections. One-to-one correlation with histopathology was obtained. Twenty-three patients with 24 lesions were included in the study. The mean age was 64.6 years (range 22-91 years); there were 16 (69.6%) males, 14 (58.3%) lesions biopsied were on head and neck region. We achieved tissue-conservation diagnosis in 100% (24/24), 13 (54.2%) were clinically equivocal lesions, six (25%) were selected for 'feature correlation' of structures on dermoscopy or RCM, and five (20.8%) for 'correlation of new/unknown' RCM features seen on follow-up. The precision biopsy technique described herein is a novel method that facilitates direct histopathological correlation of dermoscopy and RCM features. With the aids of optical imaging devices, accurate diagnosis may be achieved by minimally invasive tissue extraction.

Interpretation of the Complex Melanoma Pathology Report

An ambiguous pathologic report can present a clinical dilemma to the treating surgeon. We describe lesions ranging from the potentially benign to the likely malignant. Correctly identifying features associated with higher-risk lesions has proven challenging given the overall good prognosis and low rate of events. An appropriate treatment plan generally requires discussion between the surgeon and an experienced dermatopathologist. When clinically indicated, additional testing may be used to further support or refute a diagnosis of melanoma. The indications for these techniques, the data to support their use, and the strengths and weakness of each are reviewed.

Skin adnexal carcinoma with BRD3-NUTM2B fusion

NUT carcinomas are genetically defined epithelial neoplasms. Most tumors harbor fusions of NUTM1 with BRD4 or BRD3. Their histopathologic features have been predominantly reported as undifferentiated or poorly differentiated squamous cell carcinoma, and clinically they tend to be aggressive cancers. However, recent studies have revealed a broader spectrum of NUTM1-rearranged neoplasms with several new fusion partners and associated variable histopathologic phenotypes and clinical behaviors, including benign and malignant cutaneous poroid tumors. We report herein a primary invasive carcinoma of skin adnexal origin with a previously undescribed fusion between BRD3 and NUTM2B. The tumor occurred on the shoulder of a 7-year-old girl and was excised with negative margins. A sentinel lymph node was positive. After follow-up of 23 months, and without systemic treatment, the child remains free of tumor. This case expands the spectrum of NUT carcinomas by including a skin adnexal variant with follicular infundibular differentiation, a novel genomic aberration, and preliminary evidence of a less aggressive clinical course.

Bilateral diffuse uveal melanocytic proliferation with multifocal diffuse integumentary melanocytic proliferation paraneoplastic syndrome: A case report

Bilateral diffuse uveal melanocytic proliferation (B-DUMP) is a rare paraneoplastic syndrome typically presenting with bilateral visual loss. B-DUMP is associated with extraocular systemic malignancies with the most common being lung cancer in males and uro-gynaecological cancer in females (mainly ovarian cancer). Cutaneous and/or mucosal involvement in patients with B-DUMP has been reported but it is not well characterised. Herein, we present a female in her 70s with diagnosis of stage IV vaginal clear-cell carcinoma and metastatic melanoma of unknown primary that developed progressive bilateral loss of visual acuity compatible with 'B-DUMP'. Simultaneously, she developed multifocal bilateral bluish-greyish patches on the skin that were shown to have a proliferation of dermal melanocytes. We propose that the clinical and histopathologic cutaneous findings seen in patients with B-DUMP be termed 'diffuse integumentary melanocytic proliferation (DIMP)'.

PRAME Immunohistochemistry as an Ancillary Test for the Assessment of Melanocytic Lesions

PRAME (PReferentially expressed Antigen in MElanoma) is a melanoma-associated antigen expressed in cutaneous and ocular melanomas and some other malignant neoplasms, while its expression in normal tissue and benign tumors is limited. Detection of PRAME protein expression by immunohistochemistry in a cohort of 400 melanocytic tumors showed diffuse nuclear immunoreactivity for PRAME in most metastatic and primary melanomas. In contrast, most nevi were negative for PRAME or showed nondiffuse immunoreactivity. The difference in the extent of immunoreactivity for PRAME in unambiguous melanocytic tumors prompted the study of PRAME as an ancillary tool for evaluating melanocytic lesions in more challenging scenarios.

Immunohistochemical Detection of Cancer-Testis Antigen PRAME

Cancer-testis (CT) antigens were identified by their ability to elicit T- or B-cell immune responses in the autologous host. They are typically expressed in a wide variety of neoplasms and in normal adult tissues are restricted to testicular germ cells. PReferentially expressed Antigen of Melanoma (PRAME) is a member of the family of nonclassical CT antigens being expressed in a few other normal tissues besides testis. Interestingly, knowledge about the protein expression of many CT antigens is still incomplete due to the limited availability of reagents for their immunohistochemical detection. Here, we tested several commercially available serological reagents and identified a monoclonal antibody suitable for the immunohistochemical detection of PRAME in formalin-fixed paraffin-embedded specimens. We also tested a wide array of normal and neoplastic tissues. PRAME protein expression in normal tissues is congruent with original molecular data being present in the testis, and at low levels in the endometrium, adrenal cortex, and adult as well as fetal ovary. In tumors, there is diffuse PRAME immunoreactivity in most metastatic melanomas, myxoid liposarcomas, and synovial sarcomas. Other neoplasms such as seminomas and carcinomas of various origins including endometrial, serous ovarian, mammary ductal, lung, and renal showed an intermediate proportion of cases and variable extent of tumor cells positive for PRAME protein expression. As seen with other CT antigens, hepatocellular and colorectal carcinoma, Leydig cell tumors, mesothelioma, and leiomyosarcoma are poor expressers of PRAME.

Fusion partners of NTRK3 affect subcellular localization of the fusion kinase and cytomorphology of melanocytes

A subset of Spitz tumors harbor fusions of NTRK3 with ETV6, MYO5A, and MYH9. We evaluated a series of 22 melanocytic tumors in which an NTRK3 fusion was identified as part of the diagnostic workup. Tumors in which NTRK3 was fused to ETV6 occurred in younger patients were predominantly composed of epithelioid melanocytes and were classified by their histopathologic features as Spitz tumors. In contrast, those in which NTRK3 was fused to MYO5A were predominantly composed of spindled melanocytes arrayed in fascicles with neuroid features such as pseudo-Verocay bodies. To further investigate the effects of the fusion kinases ETV6-NTRK3 and MYO5A-NTRK3 in melanocytes, we expressed them in immortalized melanocytes and determined their subcellular localization by immunofluorescence. ETV6-NTRK3 was localized to the nucleus and diffusely within the cytoplasm and caused melanocytes to adopt an epithelioid cytomorphology. In contrast, MYO5A-NTRK3, appeared excluded from the nucleus of melanocytes, was localized to dendrites, and resulted in a highly dendritic cytomorphology. Our findings indicate that ETV6-NTRK3 and MYO5A-NTRK3 have distinct subcellular localizations and effects on cellular morphology.

Treatment of Extramammary Paget Disease and the Role of Reflectance Confocal Microscopy: A Prospective Study

BACKGROUND

Extramammary Paget disease (EMPD) poses treatment challenges. Invasive and noninvasive treatment modalities exist with variable success reported. Reflectance confocal microscopy (RCM) is emerging as an adjuvant diagnostic tool.

OBJECTIVE

To evaluate the treatment of EMPD patients and the role of RCM.

METHODS

Prospective study. Demographic and tumor characteristics were recorded. Handheld-RCM was performed and correlated with histology. Treatment, clearance, pathology, and follow-up were all recorded.

RESULTS

Thirty-six EMPD lesions in 33 patients were included. Mean age was 71.7 years, and 23 were men. Mean number of surgical stages needed to clear margins was 1.9 (SD, 0.9; 1.0-3.0 stages), and mean margin needed to clear was 1.8 cm. Reflectance confocal microscopy correlated well with scouting punch biopsies (kappa, 0.93; p < .001). Disruption of the dermoepidermal junction was associated with invasive EMPD versus in situ (83.3% vs 25.9%) on histology (p = .01).

LIMITATIONS

Relatively small sample size.

CONCLUSION

Extramammary Paget disease is challenging, and lesion demarcation is of the utmost importance. Using a staged surgical excision approach, the mean margins needed were 1.8 cm, less than previously reported. Nonsurgical modalities, including radiation therapy, imiquimod, or photodynamic therapy can be considered if surgery is not pursued. Reflectance confocal microscopy is a valuable noninvasive imaging modality for the management of EMPD.

Treatment of Metastatic Extramammary Paget Disease with Combination Ipilimumab and Nivolumab: A Case Report

Metastatic primary cutaneous extramammary Paget disease (EMPD) is a rare clinical entity with a 5-year survival <10% and no standard therapy. We report the first case to our knowledge of metastatic EMPD with treatment response to checkpoint inhibitor immunotherapy. The patient had diffusely metastatic disease and previously progressed on cytotoxic chemotherapy and a molecularly targeted agent. Treatment with four cycles of ipilimumab 1 mg/kg plus nivolumab 3 mg/kg resulted in a durable partial response lasting 7 months. Analysis of metastatic tumor tissue failed to identify known predictors of treatment response to immune checkpoint inhibitors, such as high PD-L1 expression, high tumor mutation burden, or microsatellite instability. These findings support further investigation of immune checkpoint inhibition for the management of metastatic EMPD, which currently has an abysmal prognosis and no standard therapies.

Dermal melanocytic tumor with CRTC1-TRIM11 fusion: Report of two additional cases with review of the literature of an emerging entity

"Cutaneous melanocytic tumor with CRTC1-TRIM11 fusion" (CMTCT) is a newly described, potentially novel entity that typically presents as a dermal nodule on the head and neck, extremities, and trunk of adults. Histopathologically, it is reported as a nodular or multinodular tumor composed of epithelioid and spindle cells that are variably immunoreactive for S100-protein, SOX10, and MITF along with more specific melanocytic markers such as MelanA and HMB45. With only 11 cases reported in the English literature so far, the neoplasm appears to behave in a relatively indolent fashion. Nevertheless, in one case, local recurrence and synchronous distant metastasis were evident after 13 years. Additional cases with longer follow-up are essential to determine the neoplasm's biologic behavior with more accuracy. Herein, two cases of CMTCT, one arising on the lower back of a 65-year-old female and the other on the arm of a 33-year-old female in addition to a comprehensive literature review are reported.

Differences in Melanoma Between Canada and New South Wales, Australia: A Population-Based Genes, Environment, and Melanoma (GEM) Study

In an effort to understand the difference between melanomas diagnosed in Australia (New South Wales) and Canada, where the incidence in New South Wales is almost three times greater than in Canada, and mortality is twice as high although survival is slightly more favorable, we had one pathologist review 1,271 melanomas from British Columbia and Ontario, Canada, to compare these to melanomas in New South Wales, Australia. We hypothesized that histopathologic characteristics might provide insight into divergent pathways to melanoma development. We found a number of differences in risk factors and tumor characteristics between the two geographic areas. There were higher mole counts and darker phenotypes in the Canadian patients, while the Australian patients had greater solar elastosis, more lentigo maligna melanomas, and more tumor infiltrating lymphocytes. We hypothesize that the differences observed may illustrate different etiologies – the cumulative exposure pathway among Australian patients and the nevus pathway among Canadian patients. This is one of the largest studies investigating the divergent pathway hypothesis and is particularly robust due to the evaluation of all lesions by one dermatopathologist.

Use of Ultrasmall Core-Shell Fluorescent Silica Nanoparticles for Image-Guided Sentinel Lymph Node Biopsy in Head and Neck Melanoma: A Nonrandomized Clinical Trial

IMPORTANCE

Sentinel lymph node (SLN) mapping agents approved for current surgical practice lack sufficient brightness and target specificity for high-contrast, sensitive nodal visualization.

OBJECTIVE

To evaluate whether an ultrasmall, molecularly targeted core-shell silica nanoparticle (Cornell prime dots) can safely and reliably identify optically avid SLNs in head and neck melanoma during fluorescence-guided biopsy.

DESIGN, SETTING, AND PARTICIPANTS

This nonrandomized clinical trial enrolled patients aged 18 years or older with histologically confirmed melanoma in whom SLN mapping was indicated. Exclusion criteria included known pregnancy, breast-feeding, or medical illness unrelated to the tumor. The trial was conducted between February 2015 and March 2018 at Memorial Sloan Kettering Cancer Center, with postoperative follow-up of 2 years. Data analysis was conducted from February 2015 to March 2018.

INTERVENTIONS

Patients received standard-of-care technetium Tc 99m sulfur colloid followed by a microdose administration of integrin-targeting, dye-encapsulated nanoparticles, surface modified with polyethylene glycol chains and cyclic arginine-glycine-aspartic acid-tyrosine peptides (cRGDY-PEG-Cy5.5-nanoparticles) intradermally.

MAIN OUTCOMES AND MEASURES

The primary end points were safety, procedural feasibility, lowest particle dose and volume for maximizing nodal fluorescence signal, and proportion of nodes identified by technetium Tc 99m sulfur colloid that were optically visualized by cRGDY-PEG-Cy5.5-nanoparticles. Secondary end points included proportion of patients in whom the surgical approach or extent of dissection was altered because of nodal visualization.

RESULTS

Of 24 consecutive patients enrolled (median [interquartile range] age, 64 [51-71] years), 18 (75%) were men. In 24 surgical procedures, 40 SLNs were excised. Preoperative localization of SLNs with technetium Tc 99m sulfur colloid was followed by particle dose-escalation studies, yielding optimized doses and volumes of 2 nmol and 0.4 mL, respectively, and maximum SLN signal-to-background ratios of 40. No adverse events were observed. The concordance rate of evaluable SLNs by technetium Tc 99m sulfur colloid and cRGDY-PEG-Cy5.5-nanoparticles was 90% (95% CI, 74%-98%), 5 of which were metastatic. Ultrabright nanoparticle fluorescence enabled high-sensitivity SLN visualization (including difficult-to-access anatomic sites), deep tissue imaging, and, in some instances, detection through intact skin, thereby facilitating intraoperative identification without extensive dissection of adjacent normal tissue or nerves.

CONCLUSIONS AND RELEVANCE

This study found that nanoparticle-based fluorescence-guided SLN biopsy in head and neck melanoma was feasible and safe. This technology holds promise for improving lymphatic mapping and SLN biopsy procedures, while potentially mitigating procedural risks. This study serves as a first step toward developing new multimodal approaches for perioperative care.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02106598.

The differences in clinical and dermoscopic features between in situ and invasive nevus-associated melanomas and de novo melanomas

BACKGROUND

Nevus-associated melanomas (NAM) account for 30% of all melanomas and are associated with younger age and with thinner Breslow thickness. Previous studies of NAM dermoscopy found conflicting results.

OBJECTIVE

To compare the clinical and dermoscopic features of NAM and de novo melanomas (DNM), stratified by melanoma thickness, in a relatively large cohort of patients.

METHODS

A cross-sectional study of all melanomas biopsied between 2004 and 2019 at a large cancer centre. Lesions were categorized as in situ and invasive NAM or DNM. Dermoscopic images were reviewed and annotated. Associations between melanoma subtype and dermoscopic features were analysed via logistic regression modelling. Bivariate analyses were conducted using non-parametric bootstrap and chi-squared methods.

RESULTS

The study included 160 NAM (86 in situ and 74 invasive) and 218 DNM (109 in situ and 109 invasive). NAM were associated with younger age, greater likelihood of being present on the torso, and thinner Breslow thickness. NAM were 2.5 times more likely to show a negative pigment network than DNM. In situ NAM were 2.1 and two times more likely to display dermoscopic area without definable structures and tan structureless areas than DNM, respectively. In situ melanomas were more likely to present a pigment network, and invasive melanomas more commonly presented scar-like depigmentation and shiny white structures. Streaks, blotches and shiny white structures were associated with deeper Breslow depth.

CONCLUSIONS

Even though the nevus component of NAM could not be identified dermoscopically in the current series, negative pigment network, tan structureless areas and areas without definable structures are dermoscopic clues for NAM.

Association of Multiple Aggregated Yellow-White Globules With Nonpigmented Basal Cell Carcinoma

Importance

Basal cell carcinoma (BCC) is the most common skin cancer. Dermoscopic imaging has improved diagnostic accuracy; however, diagnosis of nonpigmented BCC remains limited to arborizing vessels, ulceration, and shiny white structures.

Objective

To assess multiple aggregated yellow-white (MAY) globules as a diagnostic feature for BCC.

Design, Setting, and Participants

In this retrospective, single-center, case-control study, nonpigmented skin tumors, determined clinically, were identified from a database of lesions consecutively biopsied during a 7-year period (January 1, 2009, to December 31, 2015). A subset of tumors was prospectively diagnosed, and reflectance confocal microscopy, optical coherence tomography, and histopathologic correlation were performed. Data analysis was conducted from July 1 to September 31, 2019.

Exposures

Investigators evaluated for the presence or absence of known dermoscopic criteria. MAY globules were defined as aggregated, white-yellow structures visualized in polarized and nonpolarized light.

Main Outcomes and Measures

The primary outcome was the diagnostic accuracy of MAY globules for the diagnosis of BCC. Secondary objectives included the association with BCC location and subtype. Interrater agreement was estimated.

Results

A total of 656 nonpigmented lesions from 643 patients (mean [SD] age, 63.1 [14.9] years; 381 [58.1%] male) were included. In all, 194 lesions (29.6%) were located on the head and neck. A total of 291 (44.4%) were BCCs. MAY globules were seen in 61 of 291 BCC cases (21.0%) and in 3 of 365 other diagnoses (0.8%) (P < .001). The odds ratio for diagnosis of BCC was 32.0 (96% CI, 9.9-103.2). The presence of MAY globules was associated with a diagnosis of histologic high-risk BCC (odds ratio, 6.5; 95% CI, 3.1-14.3). The structure was never seen in cases of superficial BCCs.

Conclusions and Relevance

The findings suggest that MAY globules may have utility as a new BCC dermoscopic criterion with a high specificity. MAY globules were negatively associated with superficial BCC and positively associated with deeper-seated, histologic, higher-grade tumor subtypes.

Expanding the Spectrum of Microscopic and Cytogenetic Findings Associated With Spitz Tumors With 11p Gains

A subset of Spitz tumors is associated with a copy number increase of chromosome 11p and activating mutations of HRAS. These aberrations have been reported to occur in association with desmoplastic Spitz nevi. Little is known to what extent 11p gains can also be found in nondesmoplastic tumors. To learn more about the spectrum of microscopic and cytogenetic changes that can be seen in Spitz lesions in association with 11p gains, we reviewed the clinical and pathologic features of 40 cases. Patient ages ranged from 3 to 75 years. The most common anatomic site was the head and neck region, followed by the upper extremities. Prominent desmoplasia was present in 10 cases. Seven tumors lacked significant stromal fibrosis. Twenty tumors were mitotically active. Novel microscopic features encountered in a few cases include a tumor with a polypoid silhouette and papillomatous surface and rare atypical tumors with a deep bulbous growth pattern. Among 36 cases analyzed by single-nucleotide polymorphism array or comparative genomic hybridization, 28 tumors had gains of the entire or near-entire p-arm of chromosome 11 with no other coexisting unbalanced genomic aberration. Eight cases had additional changes; 6 of these with 1 additional aberration per case, and 2 cases had several chromosomal aberrations. We also examined a subset of tumors by fluorescence in situ hybridization for the HRAS gene locus (11p15.5). All tumors were fluorescence in situ hybridization-positive. In conclusion, we expand the spectrum of pathologic findings associated with Spitz tumors with 11p gains. This cytogenetic aberration is not restricted to desmoplastic Spitz nevi. It can also be seen in nondesmoplastic and papillomatous lesions and atypical melanocytic tumors with a deep bulbous growth. We also document that in some Spitz tumors additional cytogenetic aberrations may be found, the significance of which remains to be determined.

Therapeutic Implications of Detecting MAPK-Activating Alterations in Cutaneous and Unknown Primary Melanomas

PURPOSE

Cutaneous and unknown primary melanomas frequently harbor alterations that activate the MAPK pathway. Whether MAPK driver detection beyond BRAF V600 is clinically relevant in the checkpoint inhibitor era is unknown.

EXPERIMENTAL DESIGN

Patients with melanoma were prospectively offered tumor sequencing of 341-468 genes. Oncogenic alterations in 28 RTK-RAS-MAPK pathway genes were used to construct MAPK driver groups. Time to treatment failure (TTF) was determined for patients who received first-line programmed cell death protein 1 (PD-1) monotherapy, nivolumab plus ipilimumab, or subsequent genomically matched targeted therapies. A Cox proportional hazards model was constructed for TTF using driver group and clinical variables.

RESULTS

A total of 670 of 696 sequenced melanomas (96%) harbored an oncogenic RTK-RAS-MAPK pathway alteration; 33% had ≥1 driver. Nine driver groups varied by clinical presentation and mutational burden. TTF of PD-1 monotherapy (N = 181) varied by driver, with worse outcomes for NRAS Q61 and BRAF V600 versus NF1 or other alterations (median 4.2, 7.5, 22, and not reached; P < 0.0001). Driver group remained significant, independent of tumor mutational burden and clinical features. TTF did not vary by driver for nivolumab plus ipilimumab (N = 141). Among 172 patients with BRAF V600 wild-type melanoma who progressed on checkpoint blockade, 27 were treated with genomically matched therapy, and eight (30%) derived clinical benefit lasting ≥6 months.

CONCLUSIONS

Targeted capture multigene sequencing can detect oncogenic RTK-RAS-MAPK pathway alterations in almost all cutaneous and unknown primary melanomas. TTF of PD-1 monotherapy varies by mechanism of ERK activation. Oncogenic kinase fusions can be successfully targeted in immune checkpoint inhibitor-refractory melanoma.