Genetics of adnexal tumors: An update.

Cutaneous adnexal tumors form a vast heterogeneous group that include frequent entities that are mostly benign, as well as rare tumors that are occasionally malignant. In contrast to cutaneous tumors arising from the interfollicular epidermis that develop as a result of accumulation of UV-induced DNA damage (basal cell carcinoma, squamous cell carcinoma), the oncogenesis of adnexal tumors is related to a broad spectrum of genetic mechanisms (e.g., point mutation, fusion genes, viral integration, etc.). In this setting, specific and recurrent genetic alterations have been progressively reported, and these allow better classification of these entities. For certain of them, immunohistochemical tools are now available, enabling precise integrated histological and molecular diagnosis since certain entities are linked to well-defined alterations. In this context, we aim in this review to summarize the main molecular tools currently available for the classification of adnexal tumors.

Harmonization of programmed death-ligand 1 immunohistochemistry and mRNA expression scoring in metastatic melanoma: a multicentre analysis.

AIMS: The aim of this multicentre study was to harmonize programmed death-ligand 1 (PD-L1) immunohistochemistry (IHC) and melanoma scoring. To provide a reference for PD-L1 expression independently of the IHC protocol, PD-L1 mRNA expression was compared with IHC. METHODS AND RESULTS: Standardized PD-L1 assays (22C3, 28-8, SP142, SP263) and laboratory-developed tests (QR1, 22C3) were evaluated on three IHC platforms with a training set (seven cases). mRNA expression was determined by RNAscope (CD274/PD-L1 probe) and analysed with image analysis. PD-L1 IHC findings were scored by seven blinded pathologists using the tumour proportion score (TPS), the combined positive score (CPS), and the MELscore. This method was validated by three blinded pathologists on 40 metastatic melanomas. Concordances among various antibody/platforms were high across antibodies [intraclass correlation coefficient (ICC) >0.80 for the CPS], except for SP142. Two levels of immunostaining intensity were observed: high (QR1 and SP263) and low (28-8, 22C3, and SP142). Reproducibilities across pathologists were higher for QR1 and SP263 (ICC ≥0.87 and ICC ≥0.85 for the TPS and the CPS, respectively). QR1, SP263 and 28-8 showed the highest concordance with mRNA expression. We developed a standardized method for PD-L1 immunodetection and scoring, tested on 40 metastatic melanomas. Concordances among antibodies were excellent for all criteria, and concordances among pathologists were better for the MELscore than for other scores. CONCLUSION: Harmonization of PD-L1 staining and scoring in melanomas with good concordance is achievable with the PD-L1 IHC protocols applied to other cancers; this reproducible approach can simplify daily practice.

[The role of new molecular tests in the diagnosis of melanoma in a setting of congenital nævus in an infant]. / Apport des nouveaux tests moléculaires dans le diagnostic d'un mélanome sur nævus congénital chez un nourrisson.

INTRODUCTION: Congenital and infantile melanomas are extremely rare. We report a case of a child presenting at birth with a giant congenital nevus complicated by melanoma and on long-term follow-up with exploration using new immunohistochemistry and molecular biology tools. OBSERVATION: A new-born girl presented at birth with a large congenital cervico-mandibular tumour with para-pharyngeal extension and underlying osteolysis. At 7 months, histology and immunohistochemistry of the operative specimen revealed nodules with atypical features (mitotic figures, necrosis and positive expression of KI67 and P53 in approximatively 50 % of the melanocytic nuclei). A diagnosis was made of infantile melanoma associated with congenital nevi. Repeated surgery and monitoring (clinical and imaging) were performed. At the age of 7 years, as there was no evidence of metastatic lesions, further analyses were performed on the initial operative specimen. Investigation of transcription factor expression using immunohistochemistry, comparative genomic hybridization and histology-guided mass spectrometry, although suspect, did not in itself support a diagnosis of melanoma. Finally, at the age of 7 years, hepatic and pulmonary metastases were reported. Despite combined immunotherapy with ipilimumab and nivolumab, the child died 5 months later. CONCLUSION: This case illustrates the complexity of diagnosis of infantile melanoma and the risk of metastatic involvement long after the initial diagnosis. Diagnosis may be difficult and necessitates expert advice and the application of several recent methods to reach a conclusion and initiate appropriate treatment.

Molecular screening program to select molecular-based recommended therapies for metastatic cancer patients: analysis from the ProfiLER trial.

BACKGROUND: Antitumor activity of molecular-targeted agents is guided by the presence of documented genomic alteration in specific histological subtypes. We aim to explore the feasibility, efficacy and therapeutic impact of molecular profiling in routine setting. PATIENTS AND METHODS: This multicentric prospective study enrolled adult or pediatric patients with solid or hematological advanced cancer previously treated in advanced/metastatic setting and noneligible to curative treatment. Each molecular profile was established on tumor, relapse or biopsies, and reviewed by a molecular tumor board (MTB) to identify molecular-based recommended therapies (MBRT). The main outcome was to assess the incidence rate of genomic mutations in routine setting, across specific histological types. Secondary objectives included a description of patients with actionable alterations and for whom MBRT was initiated, and overall response rate. RESULTS: Four centers included 2579 patients from February 2013 to February 2017, and the MTB reviewed the molecular profiles achieved for 1980 (76.8%) patients. The most frequently altered genes were CDKN2A (N = 181, 7%), KRAS (N = 177, 7%), PIK3CA (N = 185, 7%), and CCND1 (N = 104, 4%). An MBRT was recommended for 699/2579 patients (27%), and only 163/2579 patients (6%) received at least one MBRT. Out of the 182 lines of MBRT initiated, 23 (13%) partial responses were observed. However, only 0.9% of the whole cohort experienced an objective response. CONCLUSION: An MBRT was provided for 27% of patients in our study, but only 6% of patients actually received matched therapy with an overall response rate of 0.9%. Molecular screening should not be used at present to guide decision-making in routine clinical practice outside of clinical trials.This trial is registered with ClinicalTrials.gov, number NCT01774409.

Genomic alterations and radioresistance in breast cancer: an analysis of the ProfiLER protocol.

BACKGROUND: Breast cancer (BC) patients with comparable prognostic features have heterogeneous outcomes, party related to a possible radiotherapy resistance leading to local-regional recurrences (LRR). The objective of the present study was to identify predictive molecular biomarkers of LRR of BC. PATIENTS AND METHODS: Genetic profile of 146 BC patients' tumours included in the ProfiLER clinical trial (NC01774409) between 2013 and 2016 were analysed using next-generation-sequencing and comparative-genomic-hybridization tests. Patients and tumour characteristics were retrospectively collected and analysed for association with genomic rearrangements (mutations, amplification, deletions). Only gene alterations observed in >3% of the tumours were selected. RESULTS: A total of 193 genomic rearrangements were identified, and 16 were observed in >3% of tumours. One was statistically correlated to the risk of local relapse. A median loco-regional progression-free survival (LRPFS) of 23.6 years was reported for PIK3CA mutation carriers (n = 31, 21.2%) versus 9.9 years for PIK3CA wild-type patients (HR 0.27, 95% CI 0.12-0.65, P = 0.002 in univariate analysis). PIK3CA mutation was identified as an independent protective factor on LRR using multivariate analysis (HR 0.29, 95% CI 0.09-0.99, P = 0.047). All other mutations, amplifications or deletions were not found associated with LRPFS. CONCLUSION: PIK3CA mutation was associated with a lower risk of local relapse in this population of BCs. This is consistent with recent studies suggesting PIK3CA to be part of biological pathways impacting the radiosensitivity.

French updated recommendations in Stage I to III melanoma treatment and management.

As knowledge continues to develop, regular updates are necessary concerning recommendations for practice. The recommendations for the management of melanoma stages I to III were drawn up in 2005. At the request of the Société Française de Dermatologie, they have now been updated using the methodology for recommendations proposed by the Haute Autorité de Santé in France. In practice, the principal recommendations are as follows: for staging, it is recommended that the 7th edition of AJCC be used. The maximum excision margins have been reduced to 2 cm. Regarding adjuvant therapy, the place of interferon has been reduced and no validated emerging medication has yet been identified. Radiotherapy may be considered for patients in Stage III at high risk of relapse. The sentinel lymph node technique remains an option. Initial examination includes routine ultrasound as of Stage II, with other examinations being optional in stages IIC and III. A shorter strict follow-up period (3 years) is recommended for patients, but with greater emphasis on imaging.

[Update to the recommendations for management of melanoma stages I to III]. / Actualisation des recommandations de prise en charge du mélanome stades I à III.

As knowledge continues to develop, regular updates are necessary concerning recommendations for practice. The recommendations for the management of melanoma stages I to III were drawn up in 2005. At the request of the Société Française de Dermatologie, they have now been updated using the methodology for recommendations proposed by the Haute Autorité de Santé. In practice, the principal recommendations are as follows: for staging, it is recommended that the 7th edition of AJCC be used. The maximum excision margins have been reduced to 2cm. Regarding adjuvant therapy, the place of interferon has been reduced and no validated emerging medication has yet been identified. Radiotherapy may be considered for patients in stage III at high risk of relapse. The sentinel lymph node technique remains an option. Initial examination includes routine ultrasound as of stage II, with other examinations being optional in stages IIC and III. A shorter strict follow-up period (3years) is recommended for patients, but with greater emphasis on imaging.

Germline BAP1 mutations predispose also to multiple basal cell carcinomas.

The BRCA1-associated protein 1 (BAP1) gene encodes a nuclear deubiquitin enzyme which acts as a tumour suppressor. Loss of function germline mutations of BAP1 have been associated with an enhanced risk of uveal and cutaneous melanomas, mesothelioma, clear cell renal cancer and atypical cutaneous melanocytic proliferations. In two independent BAP1 families, we noticed an unusual frequency of basal cell carcinomas (BCCs). Indeed, 19 BCCs were diagnosed in four patients, either of superficial (13/19) or nodular (6/19) subtype; they were all located in chronic sun-exposed areas (limbs, head or neck). Immunohistochemistry (IHC) identified in the 19 tumours, complete or partial loss of BAP1 protein nuclear expression, restricted to the BCC nests. A control study was conducted in 22 sporadic BCCs in 22 subjects under 65 without known associated BAP1 tumours: no loss of BAP1 expression was found. Overall, our observations suggest that BCCs are part of the BAP1 cancer syndrome, perhaps in relation with chronic sun exposure and melanocortin 1 receptor (MC1R) variants. In conclusion, cutaneous follow-up of BAP1 carriers should not only aim to detect melanocytic neoplasms but also BCCs.

[Recommendations for genetic testing and management of individuals genetically at-risk of cutaneous melanoma]. / Recommandations pour le diagnostic de prédisposition génétique au mélanome cutané et pour la prise en charge des personnes à risque.

Cutaneous melanoma is a multifactorial disease resulting from both environmental and genetic factors. Five susceptibility genes have been identified over the past years, comprising high-risk susceptibility genes (CDKN2A, CDK4, and BAP1 genes) and intermediate-risk susceptibility genes (MITF, and MC1R genes). The aim of this expert consensus was to define clinical contexts justifying genetic analyses, to describe the conduct of these analyses, and to propose surveillance recommendations. Given the regulatory constraints, it is recommended that dermatologists work in tandem with a geneticist. Genetic analysis may be prescribed when at least two episodes of histologically proven invasive cutaneous melanoma have been diagnosed before the age of 75 years in two 1st or 2nd degree relatives or in the same individual. The occurrence in the same individual or in a relative of invasive cutaneous melanoma with ocular melanoma, pancreatic cancer, renal cancer, mesothelioma or a central nervous system tumour are also indications for genetic testing. Management is based upon properly managed photoprotection and dermatological monitoring according to genetic status. Finally, depending on the mutated gene and the familial history, associated tumour risks require specific management (e.g. ocular melanoma, pancreatic cancer). Due to the rapid progress in genetics, these recommendations will need to be updated regularly.

An orbital perivascular epithelioid cell tumor (PEComa) in a 9-year-old boy: Case report and review of the literature.

Perivascular epithelioid cell tumors (PEComas) are a family of benign neoplasms characterized by smooth muscle and melanocytic differentiation. Orbital cases are rare. A 9-year-old male presented with a slowly growing orbital mass. Magnetic resonance imaging (MRI) revealed a well-defined orbital mass without intracranial extension. The microscopic appearance of the complete resection specimen showed large nests of epithelioid cells with wide cytoplasm containing melanin pigment and round to oval nuclei with mild cytonuclear atypia and low mitotic activity. Immunohistochemistry was positive for HMB45 and negative for melanA, smooth muscle actin, desmin and S-100 protein. Pangenomic RNA-sequencing identified an in-frame NONO-TFE3 rearrangement, and clustering data showed that the tumor's gene expression profile was grouped with other previously studied PEComas. A diagnosis of orbital pigmented PEComa with uncertain malignant potential associated with a NONO-TFE3 rearrangement was made. There was no recurrence after 1 year of follow-up.

Gene expression profiles of human melanoma cells with different invasive potential reveal TSPAN8 as a novel mediator of invasion.

BACKGROUND: Metastatic melanoma requires early detection, being treatment resistant. However, the earliest events of melanoma metastasis, and especially of dermal invasion, remain ill defined. RESULTS AND METHODS: Gene expression profiles of two clonal subpopulations, selected from the same human melanoma cell line, but differing in ability to cross the dermal-epidermal junction in skin reconstructs, were compared by oligonucleotide microarray. Of 26 496 cDNA probes, 461 were differentially expressed (>2-fold; P< 0.001), only 71 genes being upregulated in invasive cells. Among them, TSPAN8, a tetraspanin not yet described in melanoma, was upregulated at mRNA and protein levels in melanoma cells from the invasive clone, as assessed by RT-PCR, flow cytometry and western blot analysis. Interestingly, TSPAN8 was the only tetraspanin in which overexpression correlated with invasive phenotype. Flow cytometry of well-defined melanoma cell lines confirmed that TSPAN8 was exclusively expressed by invasive, but not non-invasive melanoma cells or normal melanocytes. Immunohistochemistry revealed that TSPAN8 was expressed by melanoma cells in primary melanomas and metastases, but not epidermal cells in healthy skin. The functional role of TSPAN8 was demonstrated by silencing endogenous TSPAN8 with siRNA, reducing invasive outgrowth from tumour spheroids within matrigel without affecting cell proliferation or survival. CONCLUSION: TSPAN8 expression may enable melanoma cells to cross the cutaneous basement membrane, leading to dermal invasion and progression to metastasis. TSPAN8 could be a promising target in early detection and treatment of melanoma.

A large-scale RNAi screen identifies LCMR1 as a critical regulator of Tspan8-mediated melanoma invasion.

Melanoma is the deadliest form of skin cancer owing to its proclivity to metastasise, and recently developed therapies have not yielded the expected results, because almost all patients relapse. Therefore, understanding the molecular mechanisms that underlie early invasion by melanoma cells is crucial to improving patient survival. We have previously shown that, whereas the Tetraspanin 8 protein (Tspan8) is undetectable in normal skin and benign lesions, its expression arises with the progression of melanoma and is sufficient to increase cell invasiveness. Therefore, to identify Tspan8 transcriptional regulators that could explain the onset of Tspan8 expression, thereby conferring an invasive phenotype, we performed an innovative RNA interference-based screen, which, for the first time, identified several Tspan8 repressors and activators, such as GSK3ß, PTEN, IQGAP1, TPT1 and LCMR1. LCMR1 is a recently identified protein that is overexpressed in numerous carcinomas; its expression and role, however, had not previously been studied in melanoma. The present study identified Tspan8 as the first LCMR1 target that could explain its function in carcinogenesis. LCMR1 modulation was sufficient to positively regulate endogenous Tspan8 expression, with concomitant in vitro phenotypic changes such as loss of melanoma cell-matrix adherence and increase in invasion, and Tspan8 expression promoted tumourigenicity in vivo. Moreover, LCMR1 and Tspan8 overexpression were shown to correlate in melanoma lesions, and both proteins could be downregulated in vitro by vemurafenib. In conclusion, this study highlights the importance of Tspan8 and its regulators in the control of early melanoma invasion and suggests that they may be promising new therapeutic targets downstream of the RAF-MEK-ERK signalling pathway.

A large-scale RNAi screen identifies LCMR1 as a critical regulator of Tspan8-mediated melanoma invasion.

This corrects the article DOI: 10.1038/onc.2016.219.

Primary cutaneous marginal zone B-cell lymphoma: a report of 9 cases.

BACKGROUND: Primary cutaneous B-cell lymphoma is a heterogeneous group among which marginal zone B-cell lymphoma (MZL) appears to be the most common subtype. OBJECTIVE: We analyze clinical presentation, histologic aspects, and outcome of patients with primary cutaneous MZL. METHODS: All samples classified as primary cutaneous lymphoma over the past 10 years were reviewed, and cases of primary MZL were identified. RESULTS: Nine cases of MZL were analyzed, all from the upper body region, with a predominance in elderly women. Histologic aspects included a dense, nodular, deep-seated infiltrate containing various proportions of small cells displaying a centrocyte-like, plasmacytoid or monocytoid appearance. Surface expression of CD5, CD10, and CD23 was negative. Long survival was noted but relapses in the skin, nodes, orbit, salivary glands, and breast were observed. CONCLUSION: MZL is the predominant primary cutaneous lymphoma of our study. It has distinctive histologic and clinical features as well as outcome.