Open-label, multicenter safety study of vemurafenib in patients with BRAFV600 mutation–positive metastatic melanoma

9046

Background: Vemurafenib (VEM), a BRAF kinase inhibitor, has demonstrated high response rates and improved progression-free and overall survival in pts with BRAFV600mutation–positive metastatic melanoma (mM). We present interim results from predefined subgroups from a large multicenter, open-label safety study of VEM in pts with mM (NCT01307397). Methods: Pts with BRAFV600mutation–positive histologically confirmed mM received VEM (960 mg BID) as first-line therapy or subsequent to previous therapies. Assessments for safety and efficacy were made every 28 days. Results: As of Feb 29, 2012, 2,265 pts have received VEM. Pts had a median age of 54.0 (13-95) yrs and median time since diagnosis of mM of 6.2 (0-351.9) mos. 59% had received prior systemic therapy. Median time of exposure to VEM as of the cut-off date was 3 (0.03-11.24) mos for the overall population and majority of subgroups, and approximately 2.5 mos for pts with ECOG ≥2 and age ≥75 yrs. 1537 (68%) pts were still receiving VEM at the cut-off date. 728 (32%) pts discontinued, most frequently because of PD (538/728 pts; 74%). Adverse events (AEs) were reported for 87% of all patients, with arthralgia (32%) and rash (26%) the most frequent. The incidences of AEs in the subgroups are summarized (Table). Although efficacy analyses are limited by the short duration of follow-up, six-month OS rate was 76% (95% CI 72-79%) and median PFS was 4.1 mos (95% CI 3.9-4.5 mos). Postbaseline tumor assessments were available for 63% and 30% of pts at wk 8 and 16, respectively. At wk 8 CR: 2%, PR: 57%, SD: 30%, PD: 6%. At wk 16 CR: 3%, PR: 46%, SD: 31%, PD: 15%. Conclusions: Although the overall safety profile of VEM in this study was consistent with previous clinical data, interim analyses of subgroups suggest that very elderly pts may be at higher risk of G3 AEs. Clinical trial information: NCT01307397. [Table: see text]

The genetic landscape of clinical resistance to RAF inhibition in melanoma

11009

Background: Although single-agent RAF inhibition has proved effective in metastatic BRAFV600-mutant melanoma, most patients relapse and some are intrinsically resistant. While several genetic resistance effectors have been identified, a comprehensive assessment of the genetic resistance spectrum in a large patient cohort may further inform resistance patterns and treatment strategies. Methods: Pre-treatment and post-relapse biopsies were obtained from BRAFV600melanoma patients treated with vemurafenib or dabrafenib. Whole exome sequencing of tumor and normal samples was performed to identify exome-wide mutations, insertion/deletions, and chromosomal copy number alterations. Since somatic allelic fraction comparisons across treatment time points must account for variable stromal admixture between biopsies, novel algorithms were applied to impute purity and tumor cell ploidy, thus determining the “cancer cell fraction” (CCF) of each alteration. Those with enriched CCF in post-relapse samples were nominated as potential resistance effectors. Results: 30 patients (towards a goal of 77) were sequenced to a mean depth of 145-fold coverage. In acquired resistance patients (on drug ≥ 12 weeks, n=18), NRAS Q61R (28%) and BRAF amplifications (6%) were observed. The remaining patients had multiple clonally enriched alterations in the post-relapse tumors that may drive resistance, including MEK1 mutations at residues previously noted in an in vitro mutagenesis screen for vemurafenib resistance. In the intrinsic resistance cohort (on drug < 12 weeks, n=12), multiple putative resistance mutations not previously observed in the setting of acquired resistance were identified. Conclusions: In addition to reported genetic resistance mechanisms, we identified new MEK1 mutations in resistant samples. For the majority of patients (67%) without events in these genes, computational algorithms identified new candidate drivers of RAF inhibitor resistance. Alterations that predict intrinsic or acquired resistance may also inform new approaches to melanoma therapy. Future studies incorporating longitudinal biopsies and genetic profiling will underpin a robust assessment of clinical resistance in melanoma and other cancers.

The neural crest transcription factor Brn3a is expressed in melanoma and required for cell cycle progression and survival

Pigment cells and neuronal cells both are derived from the neural crest. Here, we describe the Pit-Oct-Unc (POU) domain transcription factor Brn3a, normally involved in neuronal development, to be frequently expressed in melanoma, but not in melanocytes and nevi. RNAi-mediated silencing of Brn3a strongly reduced the viability of melanoma cell lines and decreased tumour growth in vivo. In melanoma cell lines, inhibition of Brn3a caused DNA double-strand breaks as evidenced by Mre11/Rad50-containing nuclear foci. Activated DNA damage signalling caused stabilization of the tumour suppressor p53, which resulted in cell cycle arrest and apoptosis. When Brn3a was ectopically expressed in primary melanocytes and fibroblasts, anchorage-independent growth was increased. In tumourigenic melanocytes and fibroblasts, Brn3a accelerated tumour growth in vivo. Furthermore, Brn3a cooperated with proliferation pathways such as oncogenic BRAF, by reducing oncogene-induced senescence in non-malignant melanocytes. Together, these results identify Brn3a as a new factor in melanoma that is essential for melanoma cell survival and that promotes melanocytic transformation and tumourigenesis.

Noninvasive in vivo detection and quantification of Demodex mites by confocal laser scanning microscopy

BACKGROUND

In many Demodex-associated skin diseases Demodex mites are present in abundance and seem to be at least partially pathogenic. So far all diagnostic approaches such as scraping or standardized superficial skin biopsy are (semi-)invasive and may cause discomfort to the patient.

OBJECTIVES

To see whether confocal laser scanning microscopy (CLSM) - a noninvasive method for the visualization of superficial skin layers - is able to detect and quantify D. folliculorum in facial skin of patients with rosacea.

METHODS

Twenty-five patients (34-72 years of age) with facial rosacea and 25 age- and sex-matched normal controls were examined by CLSM. Mosaics of 8 × 8 mm and 5 × 5 mm were created by scanning horizontal layers of lesional skin and quantification of mites per follicle and per area as well as follicles per area was performed.

RESULTS

In all patients D. folliculorum could be detected by CLSM and presented as roundish or lengthy cone-shaped structures. CLSM allowed the quantification of Demodex mites and revealed significant differences (P < 0·0001): the mean number of mites was 165·4 per 8 × 8 mm area and 94·2 per 5 × 5 mm area in the patients compared with 34·7 and 22·4, respectively, in the controls. The corresponding mean number of mites per follicle was 0·7 and 0·8, respectively, in the patients and 0·1 and 0·2, respectively, in the controls.

CONCLUSIONS

With the help of CLSM it is possible to detect, image and quantify Demodex mites noninvasively in facial skin of patients with rosacea.

Cytodiagnosis of erosive melanoma and basal cell carcinoma of the skin using cutaneous tissue smear

BACKGROUND

Cytomorphological assessment of erosive skin tumours offers a rapid and minimally invasive way to obtain a diagnosis. However, the studies so far conducted on this method have been relatively small.

AIM

To conduct a large retrospective study on cytomorphological assessment of erosive skin tumours.

METHODS

In this study, 86 cytological smears prepared from erosive cutaneous tumours clinically suspicious for melanoma were examined to test the diagnostic accuracy and practicability of cytomorphological evaluation of such tumours, and to compare the assessments of two investigators with different experience levels. In a subgroup of tumours, cytological assessment was compared with dermoscopic evaluation.

RESULTS

There was agreement in the cytological and histopathological results for 68 of 86 cases (79%) assessed by the experienced investigator and in 64 of 86 cases (74%) assessed by the inexperienced investigator. The diagnosis was confirmed cytologically in 39 and 34 of 42 melanomas, and in 28 and 27 of 35 basal cell carcinomas, respectively. The sensitivity of the cytodiagnosis was not significantly different between the two investigators. The dermoscopic evaluation showed good agreement with the cytological results for melanoma (82.4%), although use of dermoscopy was only possible for 49.9% of the lesions because of difficulties with the samples.

CONCLUSIONS

Cytological assessment of erosive melanoma and BCC lesions is a useful tool for gaining additional information on clinically uncertain skin tumours, and shows good agreement between different investigators.

MEK162 for patients with advanced melanoma harbouring NRAS or Val600 BRAF mutations: a non-randomised, open-label phase 2 study

BACKGROUND

Patients with melanoma harbouring Val600 BRAF mutations benefit from treatment with BRAF inhibitors. However, no targeted treatments exist for patients with BRAF wild-type tumours, including those with NRAS mutations. We aimed to assess the use of MEK162, a small-molecule MEK1/2 inhibitor, in patients with NRAS-mutated or Val600 BRAF-mutated advanced melanoma.

METHODS

In our open-label, non-randomised, phase 2 study, we assigned patients with NRAS-mutated or BRAF-mutated advanced melanoma to one of three treatment arms on the basis of mutation status. Patients were enrolled at university hospitals or private cancer centres in Europe and the USA. The three arms were: twice-daily MEK162 45 mg for NRAS-mutated melanoma, twice-daily MEK162 45 mg for BRAF-mutated melanoma, and twice-daily MEK162 60 mg for BRAF-mutated melanoma. Previous treatment with BRAF inhibitors was permitted, but previous MEK inhibitor therapy was not allowed. The primary endpoint was the proportion of patients who had an objective response (ie, a complete response or confirmed partial response). We report data for the 45 mg groups. We assessed clinical activity in all patients who received at least one dose of MEK162 and in patients assessable for response (with two available CT scans). This study is registered with ClinicalTrials.gov, number NCT01320085, and is currently recruiting additional patients with NRAS mutations (based on a protocol amendment).

FINDINGS

Between March 31, 2011, and Jan 17, 2012, we enrolled 71 patients who received at least one dose of MEK162 45 mg. By Feb 29, 2012 (data cutoff), median follow-up was 3·3 months (range 0·6-8·7; IQR 2·2-5·0). No patients had a complete response. Six (20%) of 30 patients with NRAS-mutated melanoma had a partial response (three confirmed) as did eight (20%) of 41 patients with BRAF-mutated melanoma (two confirmed). The most frequent adverse events were acneiform dermatitis (18 [60%] patients with NRAS -mutated melanoma and 15 [37%] patients with the BRAF-mutated melanoma), rash (six [20%] and 16 [39%]), peripheral oedema (ten [33%] and 14 [34%]), facial oedema (nine [30%] and seven [17%]), diarrhoea (eight [27%] and 15 [37%]), and creatine phosphokinase increases (11 [37%] and nine [22%]). Increased creatine phosphokinase was the most common grade 3-4 adverse event (seven [23%] and seven [17%]). Four patients had serious adverse events (two per arm), which included diarrhoea, dehydration, acneiform dermatitis, general physical deterioration, irregular heart rate, malaise, and small intestinal perforation. No deaths occurred from treatment-related causes.

INTERPRETATION

To our knowledge, MEK162 is the first targeted therapy to show activity in patients with NRAS -mutated melanoma and might offer a new option for a cancer with few effective treatments.

FUNDING

Novartis Pharmaceuticals.

The price of tumor control: an analysis of rare side effects of anti-CTLA-4 therapy in metastatic melanoma from the ipilimumab network

Background

Ipilimumab, a cytotoxic T-lymphocyte antigen-4 (CTLA-4) blocking antibody, has been approved for the treatment of metastatic melanoma and induces adverse events (AE) in up to 64% of patients. Treatment algorithms for the management of common ipilimumab-induced AEs have lead to a reduction of morbidity, e.g. due to bowel perforations. However, the spectrum of less common AEs is expanding as ipilimumab is increasingly applied. Stringent recognition and management of AEs will reduce drug-induced morbidity and costs, and thus, positively impact the cost-benefit ratio of the drug. To facilitate timely identification and adequate management data on rare AEs were analyzed at 19 skin cancer centers.

Methods and Findings

Patient files (n = 752) were screened for rare ipilimumab-associated AEs. A total of 120 AEs, some of which were life-threatening or even fatal, were reported and summarized by organ system describing the most instructive cases in detail. Previously unreported AEs like drug rash with eosinophilia and systemic symptoms (DRESS), granulomatous inflammation of the central nervous system, and aseptic meningitis, were documented. Obstacles included patientś delay in reporting symptoms and the differentiation of steroid-induced from ipilimumab-induced AEs under steroid treatment. Importantly, response rate was high in this patient population with tumor regression in 30.9% and a tumor control rate of 61.8% in stage IV melanoma patients despite the fact that some patients received only two of four recommended ipilimumab infusions. This suggests that ipilimumab-induced antitumor responses can have an early onset and that severe autoimmune reactions may reflect overtreatment.

Conclusion

The wide spectrum of ipilimumab-induced AEs demands doctor and patient awareness to reduce morbidity and treatment costs and true ipilimumab success is dictated by both objective tumor responses and controlling severe side effects.

High-definition optical coherence tomography for the in vivo detection of demodex mites

BACKGROUND

Demodex mites are involved in different skin diseases and are commonly detected by skin scrape tests or superficial biopsies. A new high-definition optical coherence tomography (HD-OCT) with high lateral and axial resolution in a horizontal (en-face) and vertical (slice) imaging mode might offer the possibility of noninvasive and fast in vivo examination of demodex mites.

METHODS

Twenty patients with demodex-related skin diseases and 20 age- and gender-matched healthy controls were examined by HD-OCT. Mites per follicle and follicles per field of view were counted and compared to skin scrape tests.

RESULTS

HD-OCT images depicted mites in the en-face mode as bright round dots in groups of 3-5 mites per hair follicle. In the patients with demodex-related disease, a mean number of 3.4 mites per follicle were detected with a mean number of 2.9 infested follicles per area of view compared to a mean of 0.6 mites in 0.4 infested follicles in the controls. The skin scrape tests were negative in 21% of the patients.

CONCLUSION

The innovative HD-OCT enables fast and noninvasive in vivo recognition of demodex mites and might become a useful tool in the diagnosis and treatment monitoring of demodex-related skin diseases.

Efficacy and safety of oral MEK162 in patients with locally advanced and unresectable or metastatic cutaneous melanoma harboring BRAFV600 or NRAS mutations

8511

Background: BRAF and NRAS mutations occur in 50-60% and 15-20% of cutaneous melanomas, respectively. MEK162, a selective inhibitor of the kinases MEK1 and MEK2, has shown pre-clinical activity in BRAF and NRAS mutant (mt) melanoma models. This open label, phase II study assessed the antitumor activity of MEK162 in patients (pts) with BRAFV600 and NRAS mt advanced cutaneous melanoma. Methods: MEK162 was administered orally at a starting dose of 45 mg twice daily. Treatment was until unacceptable toxicity, disease progression (PD) or investigator or patient refusal. Tumor response was assessed by CT imaging every 8 weeks (RECIST 1.0) until PD. Results: As of 16 Sept 2011, the full analysis and safety populations comprised 66 pts: 42 BRAF mt and 24 NRAS mt. Median age 58.0 years; 57.6% male; 72.7% WHO performance status 0. All NRAS pts and all but 2 BRAF (1 each stage IIIB and IIIC) pts had stage IV disease, and 87.5% of NRAS pts and 66.7% of BRAF pts had received prior therapy at study entry. Median time from 1st diagnosis to 1st dose of drug was 40.4 months. Median time on study was 10.4 and 8.5 weeks for the BRAF and NRAS arms. Relative dose intensities of 80–<100% were received by 71.4% and 70.8% of pts, respectively. Among 29 BRAF mt and 13 NRAS mt pts evaluable for efficacy, 1 confirmed and 6 unconfirmed partial responses (PRs) and 9 pts with stable disease (SD) were recorded in the BRAF arm and 2 confirmed PRs, 1 unconfirmed PR and 4 pts with SD recorded in the NRAS arm. Common treatment–related adverse events (AEs), all grades (Gs) and all pts, were rash (40.9%), diarrhea (33.3%), acneiform dermatitis (27.3%), creatine phosphokinase (CK) elevation (25.8%), fatigue (18.2%) and peripheral edema (21.2%). Central serous retinopathy-like retinal events (G 1/2 only) were reported in 8 (12.1%) pts (6 G1, 2 G2). All retinal events were reversible. G3/4 AEs in >1pt were diarrhea (4.5%) and CK elevation (15.2%). 5 pts discontinued due to toxicity. 34 pts are ongoing with more responses under current review. Conclusions: MEK162 showed clinical activity and good tolerability in pts with BRAF and NRAS mt advanced melanoma. This is the 1st targeted therapy to show activity in pts with NRAS mt melanoma.

No association of vitamin D metabolism-related polymorphisms and melanoma risk as well as melanoma prognosis: a case-control study

Melanoma is one of the most aggressive human cancers. The vitamin D system contributes to the pathogenesis and prognosis of malignancies including cutaneous melanoma. An expression of the vitamin D receptor (VDR) and an anti-proliferative effect of vitamin D in melanocytes and melanoma cells have been shown in vitro. Studies examining associations of polymorphisms in genes coding for vitamin D metabolism-related proteins (1α-hydroxylase [CYP27B1], 1,25(OH)₂D-24hydroxylase [CYP24A1], vitamin D-binding protein [VDBP]) and cancer risk are scarce, especially with respect to melanoma. Mainly VDR polymorphisms regarding melanoma risk and prognosis were examined although other vitamin D metabolism-related genes may also be crucial. In our hospital-based case–control study including 305 melanoma patients and 370 healthy controls single nucleotide polymorphisms in the genes CYP27B1 (rs4646536), CYP24A1 (rs927650), VDBP (rs1155563, rs7041), and VDR (rs757343, rs731236, rs2107301, rs7975232) were analyzed for their association with melanoma risk and prognosis. Except VDR rs731236 and VDR rs2107301, the other six polymorphisms have not been analyzed regarding melanoma before. To further improve the prevention as well as the treatment of melanoma, it is important to identify further genetic markers for melanoma risk as well as prognosis in addition to the crude phenotypic, demographic, and environmental markers used in the clinic today. A panel of genetic risk markers could help to better identify individuals at risk for melanoma development or worse prognosis. We, however, found that none of the polymorphisms tested was associated with melanoma risk as well as prognosis in logistic and linear regression models in our study population.

Fluorescence diagnostics as a guide for demarcation and biopsy of suspected anal cancer

BACKGROUND

Malignant epithelial tumors of the perianal skin are relatively rare however show high recurrence rates. A preoperative precise diagnosis and demarcation of the involved cancerous skin remains challenging but is worthwhile to minimize tissue defects and possible limitations of quality of life.

OBJECTIVES

To show the use of fluorescence diagnostics (FD) in the management of chronic perianal disease.

METHODS

FD was performed using methylaminolevulinate (MAL) for three hours topically followed by visualization with blue light (405 nm).

RESULTS

We report on two patients in whom FD helped to demarcate the involved tissue or to direct biopsy to ascertain the final diagnosis. In one patient with a history of Bowen's disease and recurrent anal carcinoma, biopsy showed extramammary Paget's disease and thus was treated by surgical anoplasty. The other patient had a history of chronic anal eczema, and FD-directed biopsy could exclude suspected malignancy so that the anal eczema was treated by local therapy.

CONCLUSIONS

FD is a non-invasive technique which can be used in the perianal region in order to delineate pathologic processes which may reduce the number of surgical interventions.

Morphology of basal cell carcinoma in high definition optical coherence tomography: en-face and slice imaging mode, and comparison with histology

BACKGROUND

Optical coherence tomography (OCT) allows real-time, in vivo examination of basal cell carcinoma (BCC). A new high definition OCT with high lateral and axial resolution in a horizontal (en-face) and vertical (slice) imaging mode offers additional information in the diagnosis of BCC and may potentially replace invasive diagnostic biopsies.

OBJECTIVES

To define the characteristic morphologic features of BCC by using high definition optical coherence tomography (HD-OCT) compared to conventional histology.

METHODS

A total of 22 BCCs were examined preoperatively by HD-OCT in the en-face and slice imaging mode and characteristic features were evaluated in comparison to the histopathological findings.

RESULTS

The following features were found in the en-face mode of HD-OCT: lobulated nodules (20/22), peripheral rimming (17/22), epidermal disarray (21/22), dilated vessels (11/22) and variably refractile stroma (19/22). In the slice imaging mode the following characteristics were found: grey/dark oval structures (18/22), peripheral rimming (13/22), destruction of layering (22/22), dilated vessels (7/22) and peritumoural bright stroma (11/22). In the en-face mode the lobulated structure of the BCC was more distinct than in the slice mode compared to histology.

CONCLUSION

HD-OCT with a horizontal and vertical imaging mode offers additional information in the diagnosis of BCC compared to conventional OCT imaging and enhances the feasibility of non-invasive diagnostics of BCC.

Selective induction of cell death in melanoma cell lines through targeting of Mcl-1 and A1

Melanoma is an often fatal form of skin cancer which is remarkably resistant against radio- and chemotherapy. Even new strategies that target RAS/RAF signaling and display unprecedented efficacy are characterized by resistance mechanisms. The targeting of survival pathways would be an attractive alternative strategy, if tumor-specific cell death can be achieved. Bcl-2 proteins play a central role in regulating survival of tumor cells. In this study, we systematically investigated the relevance of antiapoptotic Bcl-2 proteins, i.e., Bcl-2, Bcl-xL, Bcl-w, Mcl-1, and A1, in melanoma cell lines and non-malignant cells using RNAi. We found that melanoma cells required the presence of specific antiapoptotic Bcl-2 proteins: Inhibition of Mcl-1 and A1 strongly induced cell death in some melanoma cell lines, whereas non-malignant cells, i.e., primary human fibroblasts or keratinocytes were not affected. This specific sensitivity of melanoma cells was further enhanced by the combined inhibition of Mcl-1 and A1 and resulted in 60% to 80% cell death in all melanoma cell lines tested. This treatment was successfully combined with chemotherapy, which killed a substantial proportion of cells that survived Mcl-1 and A1 inhibition. Together, these results identify antiapoptotic proteins on which specifically melanoma cells rely on and, thus, provide a basis for the development of new Bcl-2 protein-targeting therapies.

Photodynamic therapy with BF-200 ALA for the treatment of actinic keratosis: results of a multicentre, randomized, observer-blind phase III study in comparison with a registered methyl-5-aminolaevulinate cream and placebo

BACKGROUND

Photodynamic therapy (PDT) with 5-aminolaevulinic acid (ALA) or its methylester [methyl-5-aminolaevulinate (MAL) or 5-amino-4-oxopentanoate] was recently ranked as first-line therapy for the treatment of actinic keratosis (AK) and is an accepted therapeutic option for the treatment of neoplastic skin diseases. BF-200 ALA (Biofrontera Bioscience GmbH, Leverkusen, Germany) is a gel formulation of ALA with nanoemulsion for the treatment of AK which overcomes previous problems of ALA instability and improves skin penetration.

OBJECTIVES

To evaluate the efficacy and safety of PDT of AKs with BF-200 ALA in comparison with a registered MAL cream and with placebo.

METHODS

The study was performed as a randomized, multicentre, observer-blind, placebo-controlled, interindividual trial with BF-200 ALA, a registered MAL cream and placebo in a ratio of 3:3:1. Six hundred patients, each with four to eight mild to moderate AK lesions on the face and/or the bald scalp, were enrolled in 26 study centres in Germany, Austria and Switzerland. Patients received one PDT. If residual lesions remained at 3months after treatment, PDT was repeated.

RESULTS

PDT with BF-200 ALA was superior to placebo PDT with respect to patient complete clearance rate (78·2% vs. 17·1%; P<0·0001) and lesion complete clearance rate (90·4% vs. 37·1%) at 3months after the last PDT. Moreover, superiority was demonstrated over the MAL cream regarding the primary endpoint patient complete clearance (78·2% vs. 64·2%; P<0·05). Significant differences in the patient and lesion complete clearance rates and severity of treatment-related adverse events were observed for the narrow- and broad-spectrum light sources.

CONCLUSIONS

BF-200 ALA is a very effective, well-tolerated new formulation for AK treatment with PDT and is superior to a registered MAL medication. Efficacies and adverse events vary greatly with the different light sources used.

Abstract C139: Detection of BRAF mutations in serum/plasma microvesicles (exosomes) of malignant melanoma patients

Background: BRAF is one of the most frequently activated oncogenes in melanoma comprising 40–60% of all mutations. About ninety percent of activating BRAF mutations occur at the V600E position enabling specific therapeutic targeting with inhibitors such as vemurafenib. Detection of the BRAF V600E mutation is therefore important for guiding treatment; however, access to tissue for testing is limited. We have recently shown that microvesicles (exosomes) isolated from serum/plasma contain RNA (exoRNA) and that tumor-derived exoRNA can be extracted from microvesicles circulating in peripheral blood. Thus the detection of the BRAF V600E mutation in blood represents a potentially useful biomarker for non-invasive diagnosis and monitoring therapeutic response.

Methods: ExoRNA was extracted from the serum and plasma of 18 patients with biopsy confirmed grade IV melanoma and 12 healthy controls. Patients were consented and samples were collected in accordance with protocols approved by the IRB at MGH and LMU. Some patients included in the study were undergoing chemotherapy or drug treatment during blood draw (13/18), while others did not receive any treatment (5/18). BRAF V600E mutation in the isolated exoRNA from serum/plasma was measured by two methods.

qPCR based assay: This assay used Taqman MGB™ probes and ARMS primers. The assay was able to detect mutations as low as &lt;0.5% and could detect to as little as 10 mutant copies in a wild-type background.

Ultra-deep Sequencing assay using Illumina HiSeq technology: Eight melanoma patient samples were used for this assay (3 from group I and 5 from group II). Using PCR, a 100 bp region of BRAF encompassing the V600E mutation locus was amplified. Illumina library preparation protocol and bioinformatics methodology was then optimized to identify BRAF V600E mutations from ultra-high coverage amplicon sequencing data. To establish the sensitivity of the sequencing platform, we also made admixtures of synthetic DNA oligos with known sequences diluting the V600E variant in up to 10,000 copies of the wild type. We found that the lower detection limit for the rare mutant variant is about 1 in 5000 wild type molecules.

Results: qPCR results indicate that 66% patients had concordance with biopsy. The healthy controls tested were all negative for V600E (0/12), giving the assay a specificity of 100% Ultra deep sequencing of exoRNA indicated that 62% patients had concordance with biopsy. By this method 2 million sequencing reads were generated per sample. The fraction of V600E to wild type variant was estimated to range from 0.05% to 10% in the samples.

Conclusions: Both qPCR and ultra-deep sequencing have identified the BRAF V600E mutation from microvesicles circulating in peripheral blood in patients with malignant melanoma. Ultra-deep sequencing further allows accurate estimation of the fraction of tumor-derived microvesicles which may be used as a surrogate marker for the actual tumor burden. ExoRNA from peripheral blood has the potential to act as a novel class of diagnostic tests for both mutation detection and therapy response monitoring without the need for invasive biopsy.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2011 Nov 12-16; San Francisco, CA. Philadelphia (PA): AACR; Mol Cancer Ther 2011;10(11 Suppl):Abstract nr C139.

The CDKN2A p.A148T variant is associated with cutaneous melanoma in Southern Brazil

Several germline mutations and sequence variants in cancer predisposition genes have been described. Among these, the CDKN2A p.A148T variant appears to be frequent in patients with melanoma, at least in certain ethnic groups. In this case-control study, we evaluated 127 patients with cutaneous melanoma and 128 controls from Southern Brazil, the region with the highest melanoma incidence rates in the country. Using PCR-RFLP, we demonstrate that CDKN2A p.A148T variant was significantly more frequent in patients with melanoma than in controls (12.6% vs 3.9%; P=0.009). There was no association between presence of the polymorphism and tumor thickness, site of the primary tumor, melanoma subtype, age at diagnosis, quantitative and qualitative number of nevi. Patients with a positive family of history for other cancers were particularly prone to carry the CDKN2A p.A148T allele. All patients with p.A148T-positive melanoma reported European ancestry, especially German, and this was confirmed using a panel of ancestry-informative INDELs. Our data suggest that CDKN2A p.A148T is a melanoma susceptibility allele in Southern Brazil and is particularly common in patients with melanoma of predominantly European ancestry.

Osteopontin expression in plasma of melanoma patients and in melanocytic tumours

BACKGROUND

While the serological tumour marker S100 is well established for the detection of metastatic melanoma, the extracellular matrix protein osteopontin (OPN) seems to be a promising novel marker for invasive melanoma.

OBJECTIVES

We analysed the potential of OPN as a serological tumour marker for metastatic melanoma and evaluated its combination with S100 and lactate dehydrogenase (LDH) levels to increase the reliability of these biomarkers for the detection of metastatic disease.

METHODS

We examined OPN in the peripheral blood of 110 melanoma patients using enzyme-linked immunosorbent assay and combined it with S100 and LDH levels. In addition, the protein expression of OPN was analysed in tissue sections of melanocytic nevi and melanomas of different progression stages by immunohistochemistry.

RESULTS

The independent comparison of S100 and OPN levels in metastatic vs. non-metastatic patients revealed a P-value <0.001 respectively. The predictiveness of OPN, S100 and LDH was 0.85, 0.89 and 0.69 as measured by the area under the receiver operating curve (AUC) respectively, while the combination of the two biomarkers OPN and S100 showed an AUC of 0.97. The optimal cut-off of the combination of OPN and S100 yielded a specificity of 85.9% and a sensitivity of 95.5%. By immunohistochemistry, OPN protein expression was detected in 29% (7/24) of melanocytic nevi, 67% (30/45) of primary melanomas and 39% (7/18) of metastatic melanomas.

CONCLUSIONS

Together, OPN seems to be a promising novel biomarker for the detection of metastatic disease in melanoma patients, showing elevated plasma levels in metastatic disease and increased protein expression in melanocytic lesions. The combination of OPN with the well-established tumour marker S100 might increase the prediction of metastases.

Analysis of predictive factors for the outcome of complete lymph node dissection in melanoma patients with metastatic sentinel lymph nodes

BACKGROUND

Sentinel lymph node biopsy (SLNB) is a widely accepted procedure to accurately stage patients with melanoma. However, there is no consensus concerning the practical consequences of a positive SLN, since a survival benefit of a complete lymph node dissection (CLND) has not yet been demonstrated.

OBJECTIVE

We wondered whether we could identify a subgroup of patients with metastatic involvement of the SLN who could be excluded from the recommendation to undergo CLND.

METHODS

At the Department of Dermatology at the University of Munich, a total of 213 patients with metastatic SLNs (24.9%) were identified among 854 patients who had undergone SLNB between 1996 and 2007. All SLN-positive patients had been advised to have CLND. Survival analyses were performed by using the Kaplan-Meier approach.

RESULTS

A total of 176 (82.6%) of 213 SLN-positive patients underwent CLND. In this group, 26 patients (14.8%) showed metastatic disease in non-sentinel lymph nodes (NSLN). The 5-year overall survival (OS) was 26.1% in NSLN-positive patients and 74% in NSLN-negative patients. SLN-positive patients who refused CLND had a better prognosis than patients with CLND. Breslow tumor thickness was significantly associated with positive CLND status with higher median values in CLND-positive than CLND-negative patients (3.03 vs 2.22 mm).

LIMITATIONS

The subgroup of patients with metastatic disease in CLND may have been too small to reach statistical significance for other tumor- or patient-related parameters. Mitotic indices of the primary melanomas had not been determined in this retrospective study; thus a possible correlation with lymph node status could not be tested.

CONCLUSION

Among SLN-positive patients, the presence of metastatic NSLN is a highly significant poor prognostic factor. Tumor thickness is a significant prognostic parameter for positive CLND status and might be considered in the decision to perform CLND in case of metastatic SLN.

Abstract 5070: Validation of a fresh-tissue based prognostic gene signature in formalin-fixed, paraffin-embedded melanomas

Melanoma incidence is rapidly increasing – with a doubling rate of 10-20 years. Precision and reliability of conventional histological and clinical staging, however, remain limited in predicting clinical outcome. On the other hand, complementary molecular prognostic markers are not yet available.

We have recently identified, for the first time, a prognostic gene signature expressed in fresh-frozen primary melanomas (n = 135), which is associated with overall survival (multivariate Cox regression analysis: p = 0.0004, hazard ratio 3.83). The clinical value of a signature-based risk score is its ability to identify patients at low risk, not identified by conventional AJCC staging, and to define risk patients in need of adjuvant therapy. The purpose of the present study was to establish analysis of the signature genes in formalin-fixed, paraffin-embedded (FFPE) melanoma tissue and to validate prognostic significance.

We developed a sensitive and robust methodology to analyze and normalize gene expression in FFPE tissue samples (some of them more than 20 years old): Total RNA was prepared from FFPE sections matching the above fresh-frozen primary melanomas (131 out of 135), quality-controled, and transcribed into cDNA. Human reference RNA was included as an internal standard. Following pre-amplification of the cDNA, expression of the nine signature genes (KRT9, KBTBD10, DCD, ECG2/SPINK7, PIP, SCGB1D2, SCGB2A2, COL6A6, HES6) and of four house-keeping genes (18S rRNA, GAPDH, GUSB, BPNT1) was quantified by real-time PCR using TaqMan assays specific for short amplicons. Gene expression data were normalized, in two steps, to correct for inter-assay technical variability (based on the reference RNA data) and inter-sample variability of RNA quality (based on the data for the house-keeping genes). Significance of correlation of FFPE gene expression data (CT values or estimated mRNA copy numbers) with data from matched fresh-frozen tissue samples (two-sided t-test) or with patient overall survival (univariate Cox regression analysis; clinical follow-up data up to 273 months) was evaluated.

The majority of FFPE primary melanomas (125 out of 131) yielded mRNA of sufficient quality. Expression of all nine signature genes in FFPE melanomas correlated with that in matched fresh-frozen samples. Significance of correlation was higher with CT values (r = 0.58 – 0.19; p = 0.001 – 0.05) than with estimated mRNA copy numbers. Expression of 7 out of the 9 genes (dichotomized CT values) in FFPE melanomas was significantly associated with patient overall survival (p = 0.0001 – 0.0335).

Thus, our prognostic melanoma gene signature was successfully transfered from fresh-frozen onto FFPE tissue samples. This facilitates clinical use of a gene-signature based prognostic risk score and, in addition, allows the retrospective prognostic analysis of primary melanomas.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 5070. doi:10.1158/1538-7445.AM2011-5070

New developments in fluorescence diagnostics

In the last decade, significant advances have been achieved in the direct viewing of the skin. Non-invasive analysis of various skin diseases in vivo has become possible by special skin display devices, allowing the physician to view the structure and properties of the skin in greater detail than can be achieved by simple visual examination. We review the last 100 years of fluorescence imaging development from clinical observation to advanced spectral imaging, addressing the role of fluorescence diagnostics (FD) in modern dermatology as well as the detection of autofluorescence.

Sorafenib and pegylated interferon-α2b in advanced metastatic melanoma: a multicenter phase II DeCOG trial

BACKGROUND

The combination of sorafenib, a multikinase inhibitor, and pegylated interferon-α2b (Peg-IFN-α2b) could potentially lead to an improved antitumoral response. Previously, combinations of interferon and sorafenib have been used in renal cell cancer.

PATIENTS AND METHODS

Patients with stage IV metastatic melanoma and no previous systemic therapies apart from adjuvant immunotherapy received Peg-IFN-α2b 3 μg/kg once per week, and sorafenib 400-mg b.i.d. for a minimum of 8 weeks. The primary study end point was disease control rate (DCR).

RESULTS

Between February 2008 and February 2009, 55 patients were enrolled with a median age of 64 years (20-85). At 8 weeks, 2 patients (3.6%) had a partial response (PR) and 14 patients a stable disease (25.5%), for a DCR of 29.1% in the intention-to-treat (ITT) population. The median progression-free survival in the ITT population was 2.47 months (95% confidence interval 1.22-3.72 months). The toxicity of sorafenib and Peg-IFN-α2b combination was characterized by mainly hematological side-effects, including one treatment-related bleeding complication with a fatal outcome. Other grade 3/4 toxic effects were fatigue and flu-like symptoms.

CONCLUSION

The combination of sorafenib and Peg-IFN-α2b showed modest clinical activity and some serious side-effects including fatal bleeding complications.

Nestin and SOX9 and SOX10 transcription factors are coexpressed in melanoma

Nestin is an intermediate filament expressed in proliferating neural progenitor cells and has been considered as a stem cell marker. Nestin is also found in melanoma and we recently demonstrated that its expression in melanoma cell lines is regulated by the transcription factors SOX9 and SOX10, but not BRN2. In this study, the expression levels of nestin, BRN2, SOX9 and SOX10 were analysed in tissues of melanoma (n = 78) and melanocytic nevi (n = 26) by immunohistochemistry. All proteins were highly expressed in primary and metastatic melanomas and, apart from BRN2, showed much lower levels in melanocytic nevi. Significant coexpression of nestin with SOX9 and SOX10 was found in primary melanoma confirming our in vitro data. Correlation analysis with clinicopathological data revealed that nestin was significantly associated with presence of ulceration in primary tumors and SOX9 with more advanced stage of disease. Our data reveal that SOX9 and SOX10 are highly expressed in melanoma and seem to have a regulatory role in nestin expression. The association with ulceration and advanced-stage tumors, respectively, suggests that nestin and SOX9 may be negative prognostic markers in melanoma.

Prognostic factors associated with sentinel lymph node positivity and effect of sentinel status on survival: an analysis of 1049 patients with cutaneous melanoma

Sentinel lymph node biopsy (SLNB) is a widely accepted staging procedure in patients with melanoma. However, it is unclear which factors predict the occurrence of micrometastasis and overall prognosis and whether SLNB should also be performed in patients with thin primary tumors. At our Department of Dermatology, University of Munich (Germany), 1049 consecutive melanoma patients were identified for SLNB between 1996 and 2007, and were followed-up to assess disease-free and overall survival. Of those, a total of 854 patients were analyzed prospectively. Patients with positive SLN were subjected to selective lymphadenectomy. The association of patient characteristics with SLN was assessed by multivariate logistic regression. Survival curves were performed using the Kaplan-Meier method. Cox proportional hazard regression with different adjustments was used to estimate the effect of SLN on survival. The detection rate of SLN was 97.24%, of which 24.9% were metastatic. Significant parameters upon SLN positivity were tumor thickness and nodular type of melanoma. The 5-year overall survival was 90.1 and 58.1% in SLN-negative and SLN-positive patients, respectively. Upon multivariate analysis tumor thickness and SLN status were significant factors influencing both disease-free survival and overall survival. In conclusion, our data confirm that SLNB is relevant as a diagnostic and staging procedure and that tumor thickness is of predictive importance. SLN status should be taken into account when designing clinical trials and informing patients about the probable course of their disease. Our data suggest that in case of a nodular melanoma subtype SLNB should also be considered at a tumor thickness below 1 mm.

Abstract 4652: Identification and validation of a novel nine-gene signature predicting clinical outcome in malignant melanoma

Incidence of malignant melanoma is rapidly increasing - with a doubling rate of 10-20 years. Conventional histopathological and clinical staging (based on Breslow tumor thickness, lymph node status, and ulceration) is largely inadequate for predicting clinical outcome of malignant melanoma. On the other hand, molecular prognostic markers are not yet available. Here, we identified a nine-gene signature which is closely associated with overall survival of melanoma patients.

To identify prognostic genes we correlated gene expression profiles of 136 primary melanomas with patient overall survival using Cox regression analysis: Initially, a comparative analysis of 20 high-risk vs. 20 low-risk primary melanomas with a clinical follow-up of more than 20 years (training cohort) was performed using whole-genome DNA microarray analysis and yielded 92 prognostically relevant candidate genes. Technical and statistical validation using TaqMan Array real-time RT-PCR and correlation of gene expression with patient overall survival reduced candidate gene number to 11. Expression of these 11 genes was further analyzed in an extended group of 91 primary melanomas (study cohort), yielding a nine-gene signature with prognostic significance. This novel prognostic melanoma gene signature was successfully validated using an independent set of 45 primary melanomas (validation cohort).

A risk score, based on the expression of the nine genes of the signature (KRT9, SPINK7/ECG2, KBTBD10, DCD, HES6, COL6A6, PIP, SCGB1D2, SCGB2A2), or any subgroup thereof, predicted patient overall survival in the study cohort (p = 0.0004, hazard ratio 3.83), independently of conventional AJCC 2002 staging. When combining gene expression score and AJCC staging, approximately two thirds (29/45, 64%) of patients with AJCC intermediate prognosis (i.e. stages IIA, IIB, and IIIA) were reclassified into good prognosis, exhibiting a long-term overall survival probability of 95%. Misclassification rate of all patients classified into good prognosis (low-risk gene score combined with AJCC stages I IIA/B, or IIIA) was very low at 4.6% and 6.25% in the training and validation cohorts, respectively.

The prognostic value of this novel signature-based risk score is its ability to identify patients at low risk, not identified by AJCC staging. This re-classification may allow these patients to stay treatment-free while experiencing excellent long-term survival. The remaining patients are risk patients and are in need of adjuvant therapies.

Note: This abstract was not presented at the AACR 101st Annual Meeting 2010 because the presenter was unable to attend.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 4652.

[A rare case of local relapsing oral melanoma]

Melanoma of the oral mucosa is an extremely rare tumor. At the time of diagnosis most melanomas are in an advanced stage because of few clinical signs. Therefore the prognosis of melanoma of the oral mucosa is often very poor. We present a 48-year-old patient with melanoma of the oral mucosa first diagnosed 22 years ago. Over 20 years several wide excisions were necessary because of multiple local relapses. Eventually, the patient died from brain metastases.

Efficacy of Low-Dose Interferon α2a 18 Versus 60 Months of Treatment in Patients With Primary Melanoma of ≥ 1.5 mm Tumor Thickness: Results of a Randomized Phase III DeCOG Trial

Purpose

Low-dose (LD) interferon (IFN) alfa (LDI) has demonstrated a consistent disease-free survival benefit for patients with clinically lymph node–negative melanoma in clinical trials. However, the optimal duration of treatment is still under discussion, and no previous trial has evaluated this question specifically. A prolongation of LDI from 18 months to 60 months might be of clinical benefit for patients with intermediate or high-risk melanoma.

Patients and Methods

Eight hundred fifty patients with resected cutaneous melanoma of at least 1.5 mm tumor thickness were included in this prospective randomized, multicenter trial in Germany and Austria. Patients had to be clinically lymph node–negative, and sentinel node biopsy (SLNB) was performed in a majority of cases. They were randomly assigned to receive 3 MU IFNα2a three times a week subcutaneously for either 18 months (arm A) or 60 months (arm B).

Results

Of 850 randomly assigned patients, 840 were eligible for evaluation after a median follow-up of 4.3 years. Tumor thickness and other relevant prognostic factors were well balanced between both groups. SLNB was performed in 635 patients (75.6%), with a positivity rate of 18.0% in arm A and 17.5% in arm B. Neither relapse-free survival (arm A, 75.6% v arm B, 72.6%; P = .72; hazard ratio, 1.05; 95% CI, 0.80 to 1.39) nor distant-metastasis–free survival (81.9% v 79.7%; P = .56; HR, 1.10; 95% CI, 0.80 to 1.52) or overall survival (85.9% v 84.9%; P = .86; HR, 1.03; 95% CI, 0.71 to 1.50) showed significant differences.

Conclusion

A prolongation of conventional LDI therapy from 18 to 60 months showed no clinical benefit in patients with intermediate and high-risk primary melanoma.

Proapoptotic signaling induced by RIG-I and MDA-5 results in type I interferon-independent apoptosis in human melanoma cells

The retinoic acid-inducible gene I (RIG-I) and melanoma differentiation-associated antigen 5 (MDA-5) helicases sense viral RNA in infected cells and initiate antiviral responses such as the production of type I IFNs. Here we have shown that RIG-I and MDA-5 also initiate a proapoptotic signaling pathway that is independent of type I IFNs. In human melanoma cells, this signaling pathway required the mitochondrial adapter Cardif (also known as IPS-1) and induced the proapoptotic BH3-only proteins Puma and Noxa. RIG-I- and MDA-5-initiated apoptosis required Noxa but was independent of the tumor suppressor p53. Triggering this pathway led to efficient activation of mitochondrial apoptosis, requiring caspase-9 and Apaf-1. Surprisingly, this proapoptotic signaling pathway was also active in nonmalignant cells, but these cells were much less sensitive to apoptosis than melanoma cells. Endogenous Bcl-xL rescued nonmalignant, but not melanoma, cells from RIG-I- and MDA-5-mediated apoptosis. In addition, we confirmed the results of the in vitro studies, demonstrating that RIG-I and MDA-5 ligands both reduced human tumor lung metastasis in immunodeficient NOD/SCID mice. These results identify an IFN-independent antiviral signaling pathway initiated by RIG-I and MDA-5 that activates proapoptotic signaling and, unless blocked by Bcl-xL, results in apoptosis. Due to their immunostimulatory and proapoptotic activity, RIG-I and MDA-5 ligands have therapeutic potential due to their ability to overcome the characteristic resistance of melanoma cells to apoptosis.

Topical methyl aminolevulinate photodynamic therapy using red light-emitting diode light for multiple actinic keratoses: a randomized study

BACKGROUND

Photodynamic therapy (PDT) is an effective treatment for actinic keratoses (AKs). Light-emitting diodes (LEDs) offer practical advantages when treating multiple lesions.

OBJECTIVE

To evaluate the efficacy and tolerability of PDT using a LED and topical methyl aminolevulinate (MAL) for treatment of multiple AKs.

METHODS AND MATERIALS

One hundred thirty-one patients with four to 10 non-pigmented, previously untreated thin or moderately thick AKs on the face or scalp were enrolled in this multicenter, double-blind, randomized, placebo-controlled study. MAL or matching placebo cream was applied to the débrided lesion surface for 3 hours before illumination with noncoherent red light (630 nm, light dose 37 J/cm(2)). Treatment was repeated 1 week later.

RESULTS

Efficacy was evaluated in 57 patients with 418 lesions treated with MAL PDT and 58 with 414 lesions treated with placebo PDT. Sixteen patients were excluded as protocol violators (not randomized). MAL PDT was superior (p< .001) to placebo PDT in lesion complete response rates (83.3%, 95% confidence interval (CI)=79.3-86.7%, vs 28.7%, 95% CI=24.4-33.4%) and patient complete response rates (all lesions showing complete response; 68.4%, 95% CI=54.8-80.1% vs 6.9%, 95% CI=1.9-16.7%).

CONCLUSIONS

Topical MAL PDT using a LED is an effective treatment for multiple AKs.