Whole-genome landscapes of major melanoma subtypes.

Melanoma of the skin is a common cancer only in Europeans, whereas it arises in internal body surfaces (mucosal sites) and on the hands and feet (acral sites) in people throughout the world. Here we report analysis of whole-genome sequences from cutaneous, acral and mucosal subtypes of melanoma. The heavily mutated landscape of coding and non-coding mutations in cutaneous melanoma resolved novel signatures of mutagenesis attributable to ultraviolet radiation. However, acral and mucosal melanomas were dominated by structural changes and mutation signatures of unknown aetiology, not previously identified in melanoma. The number of genes affected by recurrent mutations disrupting non-coding sequences was similar to that affected by recurrent mutations to coding sequences. Significantly mutated genes included BRAF, CDKN2A, NRAS and TP53 in cutaneous melanoma, BRAF, NRAS and NF1 in acral melanoma and SF3B1 in mucosal melanoma. Mutations affecting the TERT promoter were the most frequent of all; however, neither they nor ATRX mutations, which correlate with alternative telomere lengthening, were associated with greater telomere length. Most melanomas had potentially actionable mutations, most in components of the mitogen-activated protein kinase and phosphoinositol kinase pathways. The whole-genome mutation landscape of melanoma reveals diverse carcinogenic processes across its subtypes, some unrelated to sun exposure, and extends potential involvement of the non-coding genome in its pathogenesis.

The prognostic value of tumor mitotic rate in children and adolescents with cutaneous melanoma: A retrospective cohort study.

BACKGROUND: Mitotic rate is a strong predictor of outcome in adult patients with primary cutaneous melanoma, but for children and adolescent patients this is unknown. OBJECTIVE: We sought to assess the prognostic value of primary tumor mitotic rate in children and adolescents with primary melanoma. METHODS: This was a cohort study of 156 patients who were <20 years of age and who had clinically localized cutaneous melanoma. Patients <12 years of age were classified as children and those 12 to 19 years of age as adolescents. Clinicopathologic and outcome data were collected. Recurrence-free and melanoma-specific survival were calculated. Univariable and multivariable analyses were performed using Cox proportional hazard models. RESULTS: Thirteen of 156 patients (8%) were children. The mitotic rate was ≥1/mm2 in 104 patients (67%) and correlated with increasing Breslow thickness. A positive sentinel node was found in 23 of 61 patients (38%) in whom a sentinel lymph node biopsy specimen was obtained. The median follow-up was 61 months. Five-year melanoma-specific and recurrence-free survival rates were 91% and 84%, respectively. Mitotic rate was a stronger predictor of outcome than tumor thickness and was the only factor independently associated with recurrence-free survival. LIMITATIONS: This research was conducted at a single institution and the sample size was small. CONCLUSION: Mitotic rate is an independent predictor of recurrence-free survival in children and adolescents with clinically localized melanoma.

Fatal Exsanguination Following Rupture of an Iliac Artery Aneurysm in an Infant With Menkes Disease.

Menkes disease (MD) usually presents in infancy with respiratory and neurological complications. Severe isolated vasculo-connective tissue involvement in infancy is rare, and hence the precise and timely diagnosis is difficult. We report a case of an 8-week-old male infant who succumbed to acute, severe exsanguination, and hemorrhagic shock secondary to a large retroperitoneal hematoma due to rupture of a right iliac artery aneurysm. Perimortem musculoskeletal findings raised suspicion of nonaccidental injury. However, postmortem review of facial traits raised the suspicion of MD. MD was subsequently confirmed on genetic testing. Child health clinicians must remain aware of MD as a rare cause of infant vasculopathy or atypical skeletal abnormalities.

Nucleotide excision repair protein ERCC1 and tumour-infiltrating lymphocytes are potential biomarkers of neoadjuvant platinum resistance in high grade serous ovarian cancer.

OBJECTIVE: ERCC1 is a nucleotide excision repair protein that may have a role in drug resistance in high grade serous ovarian cancer (HGSOC). We hypothesized that ERCC1 expression and tumour infiltrating lymphocytes (TILS) are induced by chemotherapy in HGSOC, which may be prognostically useful. METHODS: 115 HGSOC patients were used for this study. 92 (80%) of the tissue analysed had not been exposed to platinum chemotherapy. The remaining 20% (n = 23) of cases received combination or monotherapy with carboplatin before tissue was collected. Immunohistochemistry was used to score for ERCC1 expression and morphology to score for TILs. Correlation analysis of all clinical parameters, TILs and ERCC1 and Kaplan-Meier survival analysis was performed using the ERCC1 and TILs scoring parameters (0, 1, 2 or 3). RESULTS: ERCC1 expression was 2-fold higher in the neoadjuvant chemotherapy group compared to the primary cytoreductive surgery group (p < 0.0001). The mean overall survival for the neoadjuvant group with high ERCC1 was 141.6 ±â€¯20.2 months which was significantly longer than absent ERCC1 survival of 61 + 22.6 months (p = 0.028). ERCC1 score strongly correlated with TILs score across the whole cohort (0.349, p = 1.3 × 10-4) suggesting there is a relationship between ERCC1 expression and TILs, but this requires further investigation. CONCLUSION: In conclusion, ERCC1 was identified as a potential biomarker of platinum response overall survival in HGSOC undergoing neoadjuvant HGSOC treatment.

5-Hydroxymethylcytosine is a nuclear biomarker to assess biological potential in histologically ambiguous heavily pigmented melanocytic neoplasms.

BACKGROUND: 5-Hydroxymethylcytosine (5-hmC) is an epigenetic marker detectable through immunohistochemistry (IHC) that has been shown to distinguish benign nevi from melanoma with high sensitivity and specificity. The purpose of the study was to explore its diagnostic utility in a subset of histologically challenging, heavily pigmented cutaneous melanocytic neoplasms. METHODS: 5-hmC IHC was performed on 54 heavily pigmented melanocytic tumors. Semi-quantitative analysis of immunoreactivity was correlated with clinical, pathologic and follow-up data. RESULTS: Benign melanocytic neoplasms (4 of 4 blue nevi with epithelioid change; 12 of 12 combined nevi; 5 of 5 deep penetrating nevi, DPN) exhibited strong 5-hmC nuclear reactivity. Eight heavily pigmented blue nevus-like melanomas and 7 of 8 pigmented epithelioid melanocytomas (PEM) showed significant 5-hmC loss. Five of 7 atypical DPN cases and 8 of 10 melanocytic tumors of uncertain malignant potential (MELTUMP) showed low to intermediate 5-hmC immunoreactivity. These differences were statistically significant (P-value <.0001). CONCLUSIONS: Loss of 5-hmC may be helpful in differentiating benign, diagnostically challenging, heavily pigmented melanocytic tumors from those with malignant potential. The intermediate to low 5-hmC immunoreactivity in atypical DPNs, PEMs and so-called MELTUMP categories further underscores the need to consider these neoplasms as having some potential for lethal biological behavior.

Histological pattern of Merkel cell carcinoma sentinel lymph node metastasis improves stratification of Stage III patients.

Sentinel lymph node biopsy is used to stage Merkel cell carcinoma, but its prognostic value has been questioned. Furthermore, predictors of outcome in sentinel lymph node positive Merkel cell carcinoma patients are poorly defined. In breast carcinoma, isolated immunohistochemically positive tumor cells have no impact, but in melanoma they are considered significant. The significance of sentinel lymph node metastasis tumor burden (including isolated tumor cells) and pattern of involvement in Merkel cell carcinoma are unknown. In this study, 64 Merkel cell carcinomas involving sentinel lymph nodes and corresponding immunohistochemical stains were reviewed and clinicopathological predictors of outcome were sought. Five metastatic patterns were identified: (1) sheet-like (n=38, 59%); (2) non-solid parafollicular (n=4, 6%); (3) sinusoidal, (n=11, 17%); (4) perivascular hilar (n=1, 2%); and (5) rare scattered parenchymal cells (n=10, 16%). At the time of follow-up, 30/63 (48%) patients had died with 21 (33%) attributable to Merkel cell carcinoma. Patients with pattern 1 metastases had poorer overall survival compared with patients with patterns 2-5 metastases (P=0.03), with 22/30 (73%) deaths occurring in pattern 1 patients. Three (10%) deaths occurred in patients showing pattern 5, all of whom were immunosuppressed. Four (13%) deaths occurred in pattern 3 patients and 1 (3%) death occurred in a pattern 2 patient. In multivariable analysis, the number of positive sentinel lymph nodes (1 or 2 versus >2, P<0.0001), age (<70 versus ≥70, P=0.01), sentinel lymph node metastasis pattern (patterns 2-5 versus 1, P=0.02), and immune status (immunocompetent versus suppressed, P=0.03) were independent predictors of outcome, and could be used to stratify Stage III patients into three groups with markedly different outcomes. In Merkel cell carcinoma, the pattern of sentinel lymph node involvement provides important prognostic information and utilizing this data with other clinicopathological features facilitates risk stratification of Merkel cell carcinoma patients who may have management implications.

Breslow Thickness Measurements of Melanomas Around American Joint Committee on Cancer Staging Cut-Off Points: Imprecision and Terminal Digit Bias Have Important Implications for Staging and Patient Management.

BACKGROUND: Breslow thickness is the most important prognostic factor in patients with clinically localized primary cutaneous melanomas, and its accuracy has important implications for staging and management. A review of the Melanoma Institute Australia database and population-based data for the state of New South Wales, Australia, found an unexpectedly large number of melanomas reported as being exactly 1.0 mm thick. We sought to determine possible causes for this biologically implausible finding. METHODS: The tumor thickness of 125 invasive cutaneous melanomas with a recorded Breslow thickness of 0.9-1.1 mm was remeasured and recorded by two pathologists. RESULTS: Concordance of measurements between the two pathologists was high (intraclass correlation coefficient 0.816, 95 % CI 0.733-0.873). The original measurements showed clustering at 0.9, 1.0, and 1.1 mm, whereas the review measurements did not. The original measurements staged 84 cases (72 %) as T1 and 33 (28 %) as T2, while the reviewed measurements staged 58 cases (50 %) as T1 and 59 (50 %) as T2 (p < 0.001). CONCLUSIONS: Our study demonstrated imprecision in Breslow thickness measurements and its significant impact on staging. Two potential sources of imprecision are failure to follow standardized thickness measurement guidelines and the phenomenon of terminal digit bias, not previously identified as a problem in this field. Educating pathologists about this phenomenon and the importance of utilizing ocular micrometers may improve the precision of melanoma thickness measurements around critical staging cut-off points. Clinicians must also be educated to appreciate that there is an inevitable margin of error with Breslow thickness measurements that should be considered when making management decisions.

Programmed death ligand 1 expression in triple-negative breast cancer is associated with tumour-infiltrating lymphocytes and improved outcome.

AIMS: Triple-negative breast cancer (TNBC) patients generally have a poor outcome; there is a pressing need to identify more effective therapeutic strategies. Clinical trials targeting programmed death 1/programmed death ligand 1 (PD1/PDL1) in melanoma and non-small-cell lung cancer have reported high response rates, and tumoral PDL1 expression has been suggested as a potential biomarker to enrich for patient response to these treatments. There are only very limited data to date reporting the expression of PDL1 in TNBC. METHODS AND RESULTS: PDL1 immunohistochemistry was performed on 161 primary TNBCs and assessed in the tumour as well as immune cells in the stromal compartment. PDL1 expression was very common in TNBC, expressed in the tumour cell membrane (64%), cytoplasm (80%) and stromal (93%) cellular compartments. Cytoplasmic tumoral expression of PDL1 was associated with a lower risk of breast cancer-specific death [hazard ratio (HR) 0.45, P = 0.035] while stromal PDL1 expression was associated with a lower rate of deaths from all causes (HR 0.305, P = 0.0042). Membranous expression of PDL1 was not associated with outcome. While both PDL1 expression and tumour-infiltrating lymphocytes were associated with a better outcome, only lymphovascular invasion and high tumour-infiltrating lymphocytes were independently prognostic for breast cancer-specific death. CONCLUSION: While PDL1 expression is frequent in TNBC, it was not independently prognostic. There were differences in outcome depending on the cellular compartment of PDL1 expression. These data provide further impetus for investigating the utility of immune checkpoint therapies in TNBC, given the clinical significance of tumour-infiltrating lymphocytes (TILs) and PDL1 expression in this cohort.

Tumor PD-L1 expression, immune cell correlates and PD-1+ lymphocytes in sentinel lymph node melanoma metastases.

Melanoma patients with sentinel lymph node metastases have variable 5-year survival rates (39-70%). The prognostic significance of tumor-infiltrating lymphocytes in sentinel lymph node metastases from such patients is currently unknown. Anti-PD-1/PD-L1 inhibitors have significantly improved clinical outcome in unresectable AJCC stage IIIC/IV metastatic melanoma patients, and are being trialed in the adjuvant setting in advanced stage disease, however, their role in early stage (sentinel lymph node positive) metastatic disease remains unclear. The aims of this study were to characterize, in sentinel lymph nodes, the subpopulations of lymphocytes that interact with metastatic melanoma cells and analyze their associations with outcome, and to determine tumor PD-L1 expression as this may provide a rational scientific basis for the administration of adjuvant anti-PD-1/PD-L1 inhibitors in sentinel lymph node positive metastatic melanoma patients. Sentinel lymph nodes containing metastatic melanoma from 60 treatment-naive patients were analyzed for CD3, CD4, CD8, FOXP3, PD-1, and PD-L1 using immunohistochemistry on serial sections. The results were correlated with clinicopathologic features and outcome. Positive correlations between recurrence-free/overall survival with the number of CD3+ tumor-infiltrating lymphocytes (hazard ratio=0.36 (0.17-0.76), P=0.005; hazard ratio=0.29 (0.14-0.61), P=0.0005, respectively), the number of CD4+ tumor-infiltrating lymphocytes (hazard ratio=0.34 (0.15-0.77), P=0.007; hazard ratio=0.32 (0.14-0.74), P=0.005, respectively), and the number of CD8+ tumor-infiltrating lymphocytes (hazard ratio =0.42 (0.21-0.85), P=0.013; hazard ratio =0.32 (0.19-0.78), P=0.006, respectively) were observed. There was also a negative correlation with the number of peritumoral PD-1+ lymphocytes (hazard ratio=2.67 (1.17-6.13), P=0.016; hazard ratio=2.74 (1.14-6.76), P=0.019, respectively). Tumoral PD-L1 expression was present in 26 cases (43%) but did not correlate with outcome. The findings suggest that T-cell subsets in sentinel lymph node metastases can predict melanoma patient outcome. In addition, the relatively high number of PD-L1 positive sentinel lymph node melanoma metastases provides a rationale for anti-PD-1 therapy trials in sentinel lymph node positive melanoma patients, particularly those with peritumoral PD-1+ lymphocytes.

Detailed pathological examination of completion node dissection specimens and outcome in melanoma patients with minimal (<0.1 mm) sentinel lymph node metastases.

BACKGROUND: Nonsentinel lymph nodes (NSLNs) are rarely involved in patients with minimal volume melanoma metastases in sentinel lymph nodes (SLNs). Therefore, it has been suggested that completion lymph node dissection (CLND) is not required. However, the lack of routine immunohistochemical staining and multiple sectioning may have led to failure to identify additional positive nodes. The present study sought to more reliably determine the tumor status of NSLNs in patients with minimally involved SLNs and their clinical outcome. METHODS: A total of 21 tumor-negative CLND specimens from 20 patients with SLN metastases of <0.1 mm in diameter treated between 1991 and 2013 were examined with a more detailed pathologic protocol (five new sections stained with/for H&E, S-100, HMB45, Melan-A, and H&E). Clinical follow-up data were also obtained. RESULTS: Of the 343 examined NSLNs, 1 was found to harbor a 0.18-mm subcapsular sinus metastasis. No metastases were identified in the other NSLNs. Median follow-up was 48 months (range 17-130 months). Six patients (30 %) developed a recurrence. At the end of follow-up, 15 patients (75 %) were alive without sign of melanoma recurrence and 5 patients (25 %) had died of melanoma. Estimated 5-year melanoma-specific survival was 64 %. The patient with the additional positive NSLN remains without recurrence after 130 months follow-up. CONCLUSIONS: Although the risk of additional nodal involvement is low, detailed pathologic examination may identify NSLN metastases not identified using routine protocols. Therefore, nodal clearance appears to be the safest option for these patients, pending the results of prospective trials.

Punch biopsy of melanoma causing tumour cell implantation: another peril of utilising partial biopsies for melanocytic tumours.

The recommended initial management for suspected melanoma is excisional biopsy. The use of partial biopsies of melanocytic tumours poses potential problems including misdiagnosis due to either unrepresentative sampling or the difficulty in evaluating important diagnostic features; an inaccurate assessment of Breslow thickness and other important prognostic features; and the induction of changes capable of mimicking melanoma (i.e., pseudomelanoma). Misdiagnosis, in turn, may lead to inappropriate management of the patient and an adverse outcome. In this report we document a previously unrecognised pitfall of partial biopsies of melanocytic tumours: implantation of tumour cells at the biopsy site potentially leading to the overestimation of tumour thickness or a misdiagnosis of the presence of microsatellites in the subsequent wide excision specimen.

PI3K/mTOR is a therapeutically targetable genetic dependency in diffuse intrinsic pontine glioma.

Diffuse midline glioma (DMG), including tumors diagnosed in the brainstem (diffuse intrinsic pontine glioma; DIPG), are uniformly fatal brain tumors that lack effective treatment. Analysis of CRISPR/Cas9 loss-of-function gene deletion screens identified PIK3CA and MTOR as targetable molecular dependencies across patient derived models of DIPG, highlighting the therapeutic potential of the blood-brain barrier-penetrant PI3K/Akt/mTOR inhibitor, paxalisib. At the human-equivalent maximum tolerated dose, mice treated with paxalisib experienced systemic glucose feedback and increased insulin levels commensurate with patients using PI3K inhibitors. To exploit genetic dependence and overcome resistance while maintaining compliance and therapeutic benefit, we combined paxalisib with the antihyperglycemic drug metformin. Metformin restored glucose homeostasis and decreased phosphorylation of the insulin receptor in vivo, a common mechanism of PI3K-inhibitor resistance, extending survival of orthotopic models. DIPG models treated with paxalisib increased calcium-activated PKC signaling. The brain penetrant PKC inhibitor enzastaurin, in combination with paxalisib, synergistically extended the survival of multiple orthotopic patient-derived and immunocompetent syngeneic allograft models; benefits potentiated in combination with metformin and standard-of-care radiotherapy. Therapeutic adaptation was assessed using spatial transcriptomics and ATAC-Seq, identifying changes in myelination and tumor immune microenvironment crosstalk. Collectively, this study has identified what we believe to be a clinically relevant DIPG therapeutic combinational strategy.

Elevated postmortem vitreous sodium and chloride levels distinguish saltwater drowning (SWD) deaths from immersion deaths not related to drowning but recovered from saltwater (DNRD).

A 5-year prospective study of saltwater-related deaths was undertaken in 2 medico-legal centers in Australia. This demonstrated a statistically significant elevation (P<0.01) in postmortem vitreous sodium and chloride (PMVSC) levels and sum of sodium and chloride levels in 15 cases of deaths due to saltwater drowning (SWD) in comparison with 7 immersion deaths not related to drowning but recovered from saltwater (DNRD), and with 50 case controls. From our data, PMVSC was superior to using sodium or chloride levels alone in discriminating SWD from DNRD and controls. It is proposed that in cases where bodies are retrieved from a saltwater environment and SWD is suspected, a PMVSC of 284 mmol/L or higher is consistent with SWD. Conversely, a PMVSC level of less than 258 mmol/L is inconsistent with SWD. A PMVSC between 258 and 284 mmol/L is inconclusive or noninformative, and circumstantial evidence and autopsy findings are needed to determine the cause of death. It is suggested that PMVSC measurement is a worthwhile test in determining the cause of death in cases where bodies are recovered from saltwater, especially in cases where an internal examination of the body may not be authorized or where objections to autopsy are upheld.

Repurposing Azacitidine and Carboplatin to Prime Immune Checkpoint Blockade-resistant Melanoma for Anti-PD-L1 Rechallenge.

Purpose: Drug repurposing offers the opportunity for chemotherapy to be used to reestablish sensitivity to immune checkpoint blockade (ICB) therapy. Here we investigated the clinical and translational aspects of an early phase II study of azacitidine and carboplatin priming for anti-PDL1 immunotherapy (avelumab) in patients with advanced ICB-resistant melanoma. Experimental Design: A total of 20 participants with ICB-resistant metastatic melanoma received 2 × 4-week cycles of azacitidine and carboplatin followed by ICB rechallenge with anti-PD-L1 avelumab. The primary objective was overall response rate after priming and ICB rechallenge. Secondary objectives were clinical benefit rate (CBR), progression-free survival (PFS), and overall survival (OS). Translational correlation analysis of HLA-A and PD-L1 expression, RNA sequencing, and reduced representation bisulfite sequencing of biopsies at baseline, after priming and after six cycles of avelmuab was performed. Results: The overall response rate (ORR) determined after azacitidine and carboplatin priming was 10% (2/20) with two partial responses (PR). The ORR determined after priming followed by six cycles of avelumab (week 22) was 10%, with 2 of 20 participants achieving immune partial response (iPR). The CBR for azacitidine and carboplatin priming was 65% (13/20) and after priming followed by six cycles of avelumab CBR was 35% (n = 7/20). The median PFS was 18.0 weeks [95% confidence interval (CI): 14.87-21.13 weeks] and the median OS was 47.86 weeks (95% CI: 9.67-86.06 weeks). Translational correlation analysis confirmed HLA-A generally increased after priming with azacitidine and carboplatin, particularly if it was absent at the start of treatment. Average methylation of CpGs across the HLA-A locus was decreased after priming and T cells, in particular CD8+, showed the greatest increase in infiltration. Conclusions: Priming with azacitidine and carboplatin can induce disease stabilization and resensitization to ICB for metastatic melanoma. Significance: There are limited treatments for melanoma once resistance to ICB occurs. Chemotherapy induces immune-related responses and may be repurposed to reinstate the response to ICB. This study provides the first evidence that chemotherapy can provide clinical benefit and increase OS for ICB-resistant melanoma.

Confocal microscopy, dermoscopy, and histopathology features of atypical intraepidermal melanocytic proliferations associated with evolution to melanoma in situ.

BACKGROUND: Atypical intraepidermal melanocytic proliferations (AIMP) is a descriptive term sometimes applied to biopsies that do not fulfill diagnostic criteria of melanoma. They are common on sun-damaged skin, but their definition and management are controversial. OBJECTIVE: To describe dermoscopic (DS), reflectance confocal microscopic (RCM) and histopathological features of AIMP and identify features associated with subsequent melanoma in situ (MIS). METHODS: A retrospective analysis of AIMP lesions correlated with patient outcome at two melanoma tertiary centers between 2005 and 2015. RESULTS: Thirty-four patients were included. Nine (26%) patients had MIS in subsequent biopsies. Predictors of later MIS were target-like pattern (OR:12.0 [CI: 1.23, 117.41]; P = 0.032) and high-density vascular network (OR:12 [CI: 1.23-117.41], P: 0.032) on DS, and presence of dendritic cells touching each other (OR:9.1 [CI: 1.54, 54.59], P = 0.014) on RCM. Clinical predictors of worse outcome included a previous history of MIS at the same site. Radiotherapy for AIMP had a high failure rate (all patients presented with recurrent disease, three as AIMP and two as MIS). CONCLUSIONS: Considering that most cases in this series received non-surgical treatment at baseline, we recommend close monitoring for lesions with target-like pattern and density vascular network on DS and treatment for lesions with progression of atypia and/or with "confluent" dendritic cells on RCM. Although the number of patients in this series is very low, early surgery is recommended for MIS cases that recur as AIMP.

BRAF mutation testing for patients diagnosed with stage III or stage IV melanoma: practical guidance for the Australian setting.

Targeted therapy (BRAF inhibitor plus MEK inhibitor) is now among the possible treatment options for patients with BRAF mutation-positive stage III or stage IV melanoma. This makes prompt BRAF mutation testing an important step in the management of patients diagnosed with stage III or IV melanoma; one that can help better ensure that the optimal choice of systemic treatment is initiated with minimal delay. This article offers guidance about when and how BRAF mutation testing should be conducted when patients are diagnosed with melanoma in Australia. Notably, it recommends that pathologists reflexively order BRAF mutation testing whenever a patient is found to have American Joint Committee on Cancer (AJCC)/Union for International Cancer Control (UICC) stage III or IV melanoma (i.e., any metastatic spread beyond the primary tumour) and that patient's BRAF mutation status is hitherto unknown, even if BRAF mutation testing has not been specifically requested by the treating clinician (in Australia, Medicare-subsidised BRAFV600 mutation testing does not need to be requested by the treating clinician). When performed in centres with appropriate expertise and experience, immunohistochemistry (IHC) using the anti-BRAF V600E monoclonal antibody (VE1) can be a highly sensitive and specific means of detecting BRAFV600E mutations, and may be used as a rapid and relatively inexpensive initial screening test. However, VE1 immunostaining can be technically challenging and difficult to interpret, particularly in heavily pigmented tumours; melanomas with weak, moderate or focal BRAFV600E immunostaining should be regarded as equivocal. It must also be remembered that other activating BRAFV600 mutations (including BRAFV600K), which account for ∼10-20% of BRAFV600 mutations, are not detected with currently available IHC antibodies. For these reasons, if available and practicable, we recommend that DNA-based BRAF mutation testing always be performed, regardless of whether IHC-based testing is also conducted. Advice about tissue/specimen selection for BRAF mutation testing of patients diagnosed with stage III or IV melanoma is also offered in this article; and potential pitfalls when interpreting BRAF mutation tests are highlighted.

Low tumour-infiltrating lymphocyte density in primary and recurrent glioblastoma.

Immunotherapies targeting tumour-infiltrating lymphocytes (TILs) that express the immune checkpoint molecule programmed cell death-1 (PD-1) have shown promise in preclinical glioblastoma models but have had limited success in clinical trials. To assess when glioblastoma is most likely to benefit from immune checkpoint inhibitors we determined the density of TILs in primary and recurrent glioblastoma. Thirteen cases of matched primary and recurrent glioblastoma tissue were immunohistochemically labelled for CD3, CD8, CD4 and PD-1, and TIL density assessed. CD3+ TILs were observed in all cases, with the majority of both primary (69.2%) and recurrent (61.5%) tumours having low density of TILs present. CD8+ TILs were observed at higher densities than CD4+ TILs in both tumour groups. PD-1+ TILs were sparse and present in only 25% of primary and 50% of recurrent tumours. Quantitative analysis of TILs demonstrated significantly higher CD8+ TIL density at recurrence (p = 0.040). No difference was observed in CD3+ (p = 0.191), CD4+ (p = 0.607) and PD-1+ (p = 0.070) TIL density between primary and recurrent groups. This study shows that TILs are present at low densities in both primary and recurrent glioblastoma. Furthermore, PD-1+ TILs were frequently absent, which may provide evidence as to why anti-PD-1 immunotherapy trials have been largely unsuccessful in glioblastoma.

Mind Over Matter: Confronting Challenges in Post-Mortem Brain Biobanking for Glioblastoma Multiforme.

Over the past 10 years, there has been limited progress for the treatment of brain cancer and outcomes for patients are not much improved. For brain cancer researchers, a major obstacle to biomarker driven research is limited access to brain cancer tissue for research purposes. The Mark Hughes Foundation Brain Biobank is one of the first post-mortem adult brain banks in Australia to operate with protocols specifically developed for brain cancer. Located within the Hunter New England Local Health District and operated by Hunter Cancer Biobank, the boundaries of service provided by the Brain Bank extend well into the surrounding regional and rural areas of the Local Health District and beyond. Brain cancer biobanking is challenging. There are conflicting international guidelines for best practice and unanswered questions relating to scientific, psychosocial and operational practices. To address this challenge, a best practice model was developed, informed by a consensus of existing data but with consideration of the difficulties associated with operating in regional or resource poor settings. The regional application of this model was challenged following the presentation of a donor located in a remote area, 380km away from the biobank. This required biobank staff to overcome numerous obstacles including long distance patient transport, lack of palliative care staff, death in the home and limited rural outreach services. Through the establishment of shared goals, contingency planning and the development of an informal infrastructure, the donation was facilitated within the required timeframe. This experience demonstrates the importance of collaboration and networking to overcome resource insufficiency and geographical challenges in rural cancer research programmes.

Pilot early phase II study of decitabine and carboplatin in patients with advanced melanoma.

INTRODUCTION: Resistance to targeted and immune checkpoint blockade treatment remains a major problem in patients with advanced metastatic melanoma. To overcome this problem, there needs to be a decrease in burden of disease as well as re-establishing of immune sensitivity. The aim of this early phase 2 clinical trial is to investigate a novel way of sequencing and combining decitabine and carboplatin to decrease methylation and increase DNA repair resulting in a decrease in the disease burden and to re-establish sensitivity to the immune response. METHODS AND ANALYSIS: This single-site early phase 2 clinical trial will be conducted in 30 patients with metastatic melanoma that are resistant to all approved therapies. Patients will receive 2 × 4-week cycles of decitabine 7 mg/m IVI/day for 5 days (D1-D5) followed by Carboplatin AUC 5 IVI on D8; Week 3 and Week 4 no treatment. The primary objective is to determine DNA methylation and DNA repair levels before, and immediately after treatment; quantify immune-response markers (PDL-1, PD-1, CD4/CD8, and CD68) in blood, tumor and microenvironment before treatment and after 2 cycles. The secondary outcome objective is to quantify response rate (RR) to administration of 2 cycles of decitabine and carboplatin cycle using response evaluation criteria in solid tumors (RECIST 1.1) criteria. This data will be used to calculate sample size and determine statistical analysis plan for larger Phase 2 study. ETHICS AND DISSEMINATION: Protocol version 1.1 was reviewed and approved by the Hunter New England Health Human Research Ethics Committee (Reference No: 15/12/16/3.08, NSW HREC Reference No: HREC/15/HNE/505) and site-specific approval from the Calvary Mater Hospital Newcastle, NSW, Australia (NSW SSA Reference No: SSA/16/HNE/224). Primary and secondary outcomes and safety data will be disseminated through publications. TRIAL REGISTRATION DETAILS: Australian New Zealand Clinical Trial Registry ACTRN12616000440426.