Ioana Cosgarea

Targeted next generation sequencing of mucosal melanomas identifies frequent NF1 and RAS mutations

Purpose Mucosal melanoma represents ~1% of all melanomas, frequently having a poor prognosis due to diagnosis at a late stage of disease. Mucosal melanoma differs from cutaneous melanoma not only in terms of poorer clinical outcome but also on the molecular level having e.g. less BRAF and more frequent KIT mutations than cutaneous melanomas. For the majority of mucosal melanomas oncogenic driver mutations remain unknown. Experimental Design and Results In our study, 75 tumor tissues from patients diagnosed with mucosal melanoma were analyzed, applying a targeted next generation sequencing panel covering 29 known recurrently mutated genes in melanoma. NF1 and RAS mutations were identified as the most frequently mutated genes occurring in 18.3% and 16.9% of samples, respectively. Mutations in BRAF were identified in 8.4% and KIT in 7.0% of tumor samples. Conclusions Our study identifies NF1 as the most frequently occurring driver mutation in mucosal melanoma. RAS alterations, consisting of NRAS and KRAS mutations, were the second most frequent mutation type. BRAF and KIT mutations were rare with frequencies below 10% each. Our data indicate that in mucosal melanomas RAS/NF1 alterations are frequent, implying a significant pathogenetic role for MAPK and potentially PI3K pathway activation in these tumors.

Successful treatment of refractory pyoderma gangrenosum with ustekinumab only after excision of renal cell carcinoma.

Dear Editors, Pyoderma gangrenosum is a rarely diagnosed neutrophilic disease, which is clinically characterised by very painful ulcers with violaceous, undermined borders (1–3). Even if aetiology and pathogenesis are still not completely understood an association with other systemic diseases, especially inflammatory bowel diseases, was frequently reported. Currently, other relevant comorbidities, such as rheumatic arthritis, renal dysfunctions, endocrinological and haematological diseases or neoplasms, have been described (3–5). We report a 71-year old patient first presented to our outpatient clinic 4 years ago with pyoderma gangrenosum on his shoulder. The patient suffered from chronic venous insufficiency, diabetes and arterial hypertension. We started a systemic glucocorticoid therapy in which the patient demonstrated a quick and good response. The wound healed within 2 months. After 7 months, the same patient developed new pyoderma gangrenosum on both groins after catheterisation. We restarted the systemic glucocorticoid therapy which had to be combined with cyclosporine A because of the prolonged course over more than 3 months. Both wounds healed completely. Again 3 months later, he developed a new pyoderma gangrenosum pectoral on the left hip and left shoulder, so that we restarted a systemic therapy with glucocorticoids and cyclosporine A. Due to the continuing size progress, we decided to switch to ustekinumab therapy but the patient did not show response to therapy and developed new lesions under his breast and clavicle (Figure 1). Because of the untypical clinical course, we decided to reexamine the patient. He underwent an abdominal and thoracic CT scans, which showed a renal carcinoma on the left kidney. The systemic treatments were stopped and a radical nephrectomy

SF3B1 and BAP1 mutations in blue nevus-like melanoma

Blue nevi are melanocytic tumors originating in the cutaneous dermis. Malignant tumors may arise in association with or resembling blue nevi, so called ‘blue nevus-like melanoma’, which can metastasize and result in patient death. Identifying which tumors will behave in a clinically aggressive manner can be challenging. Identifying genetic alterations in such tumors may assist in their diagnosis and prognostication. Blue nevi are known to be genetically related to uveal melanomas (eg, both harboring GNAQ and GNA11 mutations). In this study, we analyzed a large cohort (n=301) of various morphologic variants of blue nevi and related tumors including tumors diagnosed as atypical blue nevi (n=21), and blue nevus-like melanoma (n=12), screening for all gene mutations known to occur in uveal melanoma. Similar to published reports, we found the majority of blue nevi harbored activating mutations in GNAQ (53%) or GNA11 (15%). In addition, rare CYSLTR2 (1%) and PLCB4 (1%) mutations were identified. EIF1AX, SF3B1, and BAP1 mutations were also detected, with BAP1 and SF3B1 R625 mutations being present only in clearly malignant tumors (17% (n=2) and 25% (n=3) of blue nevus-like melanoma, respectively). In sequencing data from a larger cohort of cutaneous melanomas, this genetic profile was also identified in tumors not originally diagnosed as blue nevus-like melanoma. Our findings suggest that the genetic profile of coexistent GNAQ or GNA11 mutations with BAP1 or SF3B1 mutations can aid the histopathological diagnosis of blue nevus-like melanoma and distinguish blue nevus-like melanoma from conventional epidermal-derived melanomas. Future studies will need to further elucidate the prognostic implications and appropriate clinical management for patients with tumors harboring these mutation profiles.

Activating cysteinyl leukotriene receptor 2 (CYSLTR2) mutations in blue nevi

Blue nevi are common melanocytic tumors arising in the dermal layer of the skin. Similar to uveal melanomas, blue nevi frequently harbor GNAQ and GNA11 mutations. Recently, recurrent CYSLTR2 and PLCB4 mutations were identified in uveal melanomas not harboring GNAQ or GNA11 mutations. All four genes (GNAQ, GNA11, CYSLTR2, and PLCB4) code for proteins involved in the same signaling pathway, which is activated by mutations in these genes. Given the related functional consequences of these mutations and the known genetic similarities between uveal melanoma and blue nevi, we analyzed a cohort of blue nevi to investigate whether CYSLTR2 and PLCB4 mutations occur in tumors lacking GNAQ or GNA11 mutations (as in uveal melanoma). A targeted next-generation sequencing assay covering known activating mutations in GNAQ, GNA11, CYSLTR2, PLCB4, KIT, NRAS, and BRAF was applied to 103 blue nevi. As previously reported, most blue nevi were found to harbor activating mutations in GNAQ (59%, n=61), followed by less frequent mutations in GNA11 (16%, n=17). Additionally, one BRAF (1%) and three NRAS (3%) mutations were detected. In three tumors (3%) harboring none of the aforementioned gene alterations, CYSLTR2 mutations were identified. All three CYSLTR2 mutations were the same c.386T>A, L129Q mutation previously identified in uveal melanoma that has been shown to lead to increased receptor activation and signaling. In summary, our study identifies CYSLTR2 L129Q alterations as a previously unrecognized activating mutation in blue nevi, occuring in a mutually exclusive fashion with known GNAQ and GNA11 mutations. Similar to GNAQ and GNA11 mutations, CYSLTR2 mutations, when present, are likely defining pathogenetic events in blue nevi.

A smoking prevention photoageing intervention for secondary schools in Brazil delivered by medical students: protocol for a randomised trial

Introduction Most smokers start smoking during their early adolescence, often with the idea that smoking is glamorous; the dramatic health consequences are too far in the future to fathom. We recently designed and tested an intervention that takes advantage of the broad availability of mobile phones as well as adolescents’ interest in their appearance. A free photoageing mobile app (Smokerface) was implemented by medical students in secondary schools via a novel method called mirroring. The pupils’ altered three-dimensional selfies on tablets were ‘mirrored’ via a projector in front of their whole grade. This is the first randomised trial to measure the effectiveness of the mirroring approach on smoking behaviour in secondary schools. Methods and analysis The mirroring intervention, which lasts 45 min, is implemented by Brazilian medical students in at least 35 secondary school classes with 21 participants each (at least 35 classes with 21 participants for control) in February 2018 in the city of Itauna, Brazil. External block randomisation via computer is performed on the class level with a 1:1 allocation. In addition to sociodemographic data, smoking behaviour is measured via a paper–pencil questionnaire before, 3 and 6 months postintervention plus a random carbon monoxide breathing test at baseline and end line. The primary outcome is cigarette smoking in the past week at 6 months follow-up. Smoking behaviour (smoking onset, quitting) and effects on the different genders are studied as secondary outcomes. Analysis is by intention to treat. Ethics and dissemination Ethical approval is obtained from the ethics committee of the University of Itauna in Brazil. Results will be disseminated at conferences, in peer-reviewed journals, throughout the Education Against Tobacco network social media channels and on our websites. Trial registration number NCT03178227.

Corticosteroids Augment BRAF Inhibitor Vemurafenib Induced Lymphopenia and Risk of Infection

We have previously demonstrated an impact of the BRAF inhibitor vemurafenib on patient lymphocyte counts. In the current study, the extent to which concomitant use of corticosteroids in BRAF inhibitor treated patients affects lymphocyte counts and predisposes to infection was investigated. A cohort of 102 patients receiving either the selective BRAF inhibitor vemurafenib or dabrafenib was analyzed. The amount of patients receiving either medication with or without systemic corticosteroids (dexamethasone) was determined and lymphocyte counts before and under therapy assessed. Additionally, the number and severity of infections occurring in these groups was analyzed. Vemurafenib treatment led to a considerable decrease in lymphocyte cell counts, with 62.3% of patients having lymphopenia. Dabrafenib treated patients only rarely demonstrated lymphopenia (12.5%). Dexamethasone co-administration further diminished lymphocyte counts. Lymphopenias were observed in 84.6% of patients receiving vemurafenib and dexamethasone. In our cohort, infections were noted in 9 patients, 4 of these were severe and 2 eventually fatal. All 9 cases with infections demonstrated lymphopenia, 8 of these had received dexamethasone and 7 of these a therapy with vemurafenib. Our findings demonstrate a significant lymphopenia in patients treated with the BRAF inhibitor vemurafenib, which is further augmented by dexamethasone and predisposes to infection. If validated in other studies, risk of infection should be considered when applying corticosteroids in combination with BRAF inhibitors, in particular vemurafenib.

Oncogene status as a diagnostic tool in ocular and cutaneous melanoma

The majority of human tumours can be easily and correctly diagnosed based on clinical information and pathological assessment. In some cases however, correct diagnosis can prove difficult. In such cases, molecular approaches can be of significant diagnostic value. In recent years, the understanding of genetic alterations has greatly increased. In cutaneous melanoma, it is now well recognised, that 70-80% of tumours harbour BRAF and NRAS mutations. These mutations never occur in uveal melanoma. On the other hand activating GNAQ and GNA11 mutations are found in ∼90% of uveal melanomas, and are exceptionally rare in other melanomas (<1%). Here, we demonstrate a number of melanoma cases, where distinguishing if a tumour was of cutaneous or ocular origin was not possible based on clinical and pathological assessment. In these cases there was either atypical clinical presentation or metastasis of unclear primary. Histological distinction between uveal and cutaneous melanomas, especially at the stage of metastasis, is not reliable as they can be morphologically very similar. In all cases we present, a simple genetic assessment of oncogene mutation status was able to clearly define the melanoma type. This type of genetic assessment is of great diagnostic value and due to its simplicity could be performed in routine clinical practice even in smaller institutions.

Atypical fibroxanthoma and pleomorphic dermal sarcoma harbor frequent NOTCH1/2 and FAT1 mutations and similar DNA copy number alteration profiles

Atypical fibroxanthomas and pleomorphic dermal sarcomas are tumors arising in sun-damaged skin of elderly patients. They have differing prognoses and are currently distinguished using histological criteria, such as invasion of deeper tissue structures, necrosis and lymphovascular or perineural invasion. To investigate the as-yet poorly understood genetics of these tumors, 41 atypical fibroxanthomas and 40 pleomorphic dermal sarcomas were subjected to targeted next-generation sequencing approaches as well as DNA copy number analysis by comparative genomic hybridization. In an analysis of the entire coding region of 341 oncogenes and tumor suppressor genes in 13 atypical fibroxanthomas using an established hybridization-based next-generation sequencing approach, we found that these tumors harbor a large number of mutations. Gene alterations were identified in more than half of the analyzed samples in FAT1, NOTCH1/2, CDKN2A, TP53, and the TERT promoter. The presence of these alterations was verified in 26 atypical fibroxanthoma and 35 pleomorphic dermal sarcoma samples by targeted amplicon-based next-generation sequencing. Similar mutation profiles in FAT1, NOTCH1/2, CDKN2A, TP53, and the TERT promoter were identified in both atypical fibroxanthoma and pleomorphic dermal sarcoma. Activating RAS mutations (G12 and G13) identified in 3 pleomorphic dermal sarcoma were not found in atypical fibroxanthoma. Comprehensive DNA copy number analysis demonstrated a wide array of different copy number gains and losses, with similar profiles in atypical fibroxanthoma and pleomorphic dermal sarcoma. In summary, atypical fibroxanthoma and pleomorphic dermal sarcoma are highly mutated tumors with recurrent mutations in FAT1, NOTCH1/2, CDKN2A, TP53, and the TERT promoter, and a range of DNA copy number alterations. These findings suggest that atypical fibroxanthomas and pleomorphic dermal sarcomas are genetically related, potentially representing two ends of a common tumor spectrum and distinguishing these entities is at present still best performed using histological criteria.

Update on the clinical use of kinase inhibitors in melanoma

The identification of targetable molecules in cellular signaling pathways represents a milestone in the treatment of melanoma. Selective inhibitors of these molecules, known as phosphokinases, allow for individual signaling pathways to be “switched off”. This is of particular importance for tumors in which these pathways are constitutively activated by mutations in genes encoding said molecules. Especially patients with BRAF‐mutated melanomas significantly benefit from kinase inhibitor therapies, with the current standard of combined BRAF and MEK inhibition providing very good long‐term disease control. Such regimens have been shown to achieve a progression‐free survival of more than ten months and an overall survival of more than two years, along with good quality of life. Given that the majority of patients develop secondary resistance during long‐term kinase inhibitor therapy, current clinical trials are geared towards finding suitable drug combinations including inhibitors of other signaling pathways as well as immune checkpoint inhibitors. The present review highlights targeted therapies for melanoma currently available as well as potential future options presently under clinical investigation.

NF1 mutations in conjunctival melanoma.

BackgroundConjunctival melanoma is a potentially deadly eye tumour. Despite effective local therapies, tumour recurrence and metastasis remain frequent. The genetics of conjunctival melanomas remain incompletely understood.MethodsA large cohort of 63 conjunctival melanomas was screened for gene mutations known to be important in other melanoma subtypes by targeted next-generation sequencing. Mutation status was correlated with patient prognosis.ResultsFrequent mutations in genes activating the MAP kinase pathway were identified. NF1 mutations were most frequent (n = 21, 33%). Recurrent activating mutations were also identified in BRAF (n = 16, 25%) and RAS genes (n = 12, 19%; 11 NRAS and 1 KRAS).ConclusionsSimilar to cutaneous melanomas, conjunctival melanomas can be grouped genetically into four groups: BRAF-mutated, RAS-mutated, NF1-mutated and triple wild-type melanomas. This genetic classification may be useful for assessment of therapeutic options for patients with metastatic conjunctival melanoma