Does preoperative imaging for scalp non-melanocytic skin cancer accurately predict invasion of the cranial vault? A systematic review and meta-analysis.

PURPOSE: This study aimed to determine the diagnostic accuracy of CT and MRI in the preoperative detection of bone involvement for non-melanoma skin cancers (NMSCs) located on the scalp. This study further aimed to evaluate the predictive value of these imaging modalities in determining the need for craniectomy and to identify gaps in the existing literature. METHODS: Electronic searches of the MEDLINE, Embase, Cochrane and Google Scholar databases were performed for English language studies of any type. Studies reporting detection or exclusion of histopathologically confirmed bone involvement through preoperative imaging were identified according to PRISMA guidelines. Studies reporting dural involvement, non-scalp tumours, and lacking tumour type(s) or outcome data were excluded. Outcomes were preoperative imaging result and histopathologically confirmed bone invasion. Meta-analysis was performed and sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were calculated (excluding case report and MRI data due to insufficient quality and quantity respectively). RESULTS: Four studies with a total of 69 patients were included in the final review, of which two studies totalling 66 patients were included in the meta-analysis. Preoperative CT had a sensitivity of 38%, specificity of 98%, PPV of 90% and NPV of 73%. CONCLUSIONS: The available data suggests that a preoperative CT finding of calvarial involvement by a scalp NMSC is likely to be real, but the absence of such a finding is unreliable. Current evidence suggests that preoperative imaging cannot exclude the necessity for craniectomy and future research is needed, particularly on the role of MRI.

Has the advent of modern adjuvant systemic therapy for melanoma rendered sentinel node biopsy unnecessary?

The prognostic value of sentinel node biopsy (SNB) is well established and SNB was therefore adopted as a requirement for pathological staging of melanomas>1 mm thick in the American Joint Committee on Cancer (AJCC) 8th edition. Consequently, a negative SNB status became an eligibility criterion for clinical trials of adjuvant systemic therapy in resected stage IIB/C melanoma. However, since the Keynote 716 trial demonstrated an improvement in relapse-free survival (RFS) in patients with Stage IIB/C melanoma, all of whom had SNB staging, some have argued that SNB is no longer required for patients with T3 and T4 primary melanomas. The rationale for omitting SNB is that these patients will be able to access adjuvant immunotherapy regardless of SNB status, avoiding the costs and potential complications of SNB. However, this argument overlooks the prognostic value of knowing a patient's nodal status and the therapeutic benefit of SNB in regional disease control. Based on extrapolation of data from multiple sources, we demonstrate that the risk of regional node-field relapse with SNB and immunotherapy for T3b and T4 melanomas is around 7-9% but is 20-27% without SNB. Similarly, the node-field recurrence rate with SNB alone is around 14% compared to around 40% with no SNB or immunotherapy. Consequently, in the absence of prospective data, we propose that the optimal management of the regional node-field for high-risk T3b and T4 primary melanomas is likely to be achieved by combining SNB and adjuvant immunotherapy for those patients who are suitable, rather than either treatment alone.

Immunotherapy in advanced cutaneous squamous cell carcinoma: Sydney west cancer network experience.

BACKGROUND: Cutaneous squamous cell carcinoma (CSCC) is the second most common malignancy in the Caucasian population. A minority of cases are inoperable at presentation, recur or develop metastatic disease with a historical 5-year overall survival of ~10%. Treatment options in this setting are generally palliative. Immunotherapy has emerged as a new paradigm in managing these patients. METHODS: Patients presenting to Sydney West Cancer Network with locally advanced or metastatic CSCC treated with the anti-PD1 agent cemiplimab were identified. Response to treatment was objectively assessed based on RECIST1.1 or PERCIST criteria. Primary end point was objective response rate (ORR). Secondary end points included progression-free survival (PFS), overall survival (OS), therapy toxicity, and predictors of treatment response. RESULTS: A total of 19 patients were identified with a median age of 76 (range 56-94) and 4 immunosuppressed. The longest follow up duration was 28 months. ORR, complete response (CR), and partial response (PR) were 68% (13/19), 53% (10/19), and 16% (3/19), respectively. Median PFS was 12 months (95% CI 9-14) whilst median OS was not reached by end of study. Responders (CR or PR) had significantly superior OS compared to those with no response (P < 0.01). A primary site of head and neck cancer was significantly associated with ORR (P = 0.04). A single patient experienced Grade 3 toxicity with the rest being Grades 0-1. CONCLUSION: This study confirms the clinical efficacy of cemiplimab in patients with advanced CSCC with many experiencing a durable response and an acceptable adverse effect profile.

Merkel cell carcinoma in situ: A systematic review of prognosis and management.

BACKGROUND: Merkel cell carcinoma (MCC) is a rare primary cutaneous neuroendocrine tumour. While dermally invasive MCC is known to have a five-year survival of only 30-40%, the prognosis and management of MCC in situ (MCCis) is not widely reported. OBJECTIVE: We present a systematic review to elucidate the prognosis and management of MCCis. METHODS: We performed a systematic review, searching three databases to 01 June 2021. Case reports, cohort studies, clinical trials and literature reviews were considered for inclusion. RESULTS: We identified 26 cases of MCCis published in the literature with a median age of 74 years and involving 19 males and 7 females. Most cases were on the face and neck (n = 17), followed by upper limb (n = 8) and lower limb (n = 1). Sentinel lymph node biopsy was performed in three patients, and all were negative. One subject underwent adjuvant radiotherapy. No MCCis-associated deaths were reported. CONCLUSION: This review suggests that MCCis has an excellent prognosis with minimal, if any, risk of mortality and a very low risk of dermal invasion and recurrence when treated with wide local excision alone. Sentinel lymph node biopsy is unlikely to be useful for MCCis.

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.

Survival Outcomes of Salvage Metastasectomy After Failure of Modern-Era Systemic Therapy for Melanoma.

BACKGROUND: Metastasectomy for selected patients with melanoma was associated with improved survival in the era before effective systemic therapy. Emerging evidence shows that these benefits persist even in this era of BRAF-targeted therapy and immune checkpoint inhibitor immunotherapy. This study aimed to evaluate the outcomes of salvage metastasectomy after failure of systemic therapy. METHODS: Stage 3 or 4 melanoma patients with extracranial disease progression after at least 4 weeks of systemic treatment between 2009 and 2020 were identified and categorized as resected to no evidence of disease (NED), non-progressive residual disease (NPRD), or progressive residual disease (PRD). Systemic therapy was stratified into BRAF-targeted therapy, immune checkpoint inhibitor immunotherapy, or both. The end points of overall survival (OS), progression-free survival (PFS), and locoregional disease control (LRC) were assessed using Kaplan-Meier curves. Uni- and multivariable Cox regression procedures were used to examine factors associated with OS, PFS and LRC. RESULTS: The study enrolled 190 patients. Among all the patients, the 5-year OS from metastatectomy was 52%, the 3-year PFS was 21%, and the 5-year LRC was 61%. After resection to NED, NPRD, and PRD, the 5-year OS values were 69%, 62% and 8%, respectively. Fewer lines of preoperative therapy, use of preoperative immunotherapy, and resection to NED were predictors of improved OS. After resection to NED, NPRD, and PRD, the 3-year PFS values were 23%, 24% and 10%, and the 5-year LRC values were 61%, 72% and 34%, respectively. CONCLUSIONS: Salvage metastasectomy was associated with durable survival and disease control, particularly after resection to NED, preoperative immunotherapy, and fewer lines of preoperative systemic therapy.

Immunotherapy in advanced Merkel cell carcinoma: Sydney west cancer network experience.

INTRODUCTION: Merkel cell carcinoma (MCC) is a highly aggressive skin cancer with no survival benefit demonstrated using palliative cytotoxic chemotherapy in the setting of metastatic MCC. Recently, immune checkpoint inhibitors (anti-PD-L1/PD1) have been approved in this setting after durable clinical response was demonstrated in several clinical trials. In this series, we present a multicentre real-world experience in using anti-PD-L1/PD1 in advanced MCC. METHODS: A retrospective review was performed of all patients with metastatic MCC who were treated with at least one dose of anti-PD-L1/PD1 presenting to Sydney West Cancer Network (Westmead, Nepean and Blacktown hospitals) was performed between 2016 and 2020. Treatment response was assessed based on morphologic and/or metabolic changes of the disease on FDG-PET/CT scans. Primary end point investigated was objective response rate. Secondary outcomes included therapy toxicity, disease control and overall survival. RESULTS: Thirteen patients received anti-PD-L1/PD1 with a median age of 82 (range 62-89). Two patients had undergone prior palliative chemotherapy. The median follow-up time was 17 months (range 2-34). The overall, complete and partial response rates were 77% (10), 54% (7) and 23% (3), respectively. Treatment-related grade 1 or 2 toxicity was experienced by 69% with only 2 cases of greater severity. The median progression-free survival and overall survival were 18 months (95% CI 10-26 months) and 33 months (95% CI range 7.6-58.4 months), respectively. CONCLUSIONS: Consistent with clinical trial results, anti-PD-L1/PD1 therapy in this small series demonstrated efficacy and safety in patients with metastatic MCC.

Outcomes of patients with metastatic cutaneous squamous cell carcinoma to the axilla: a multicentre cohort study.

BACKGROUND: Metastatic cutaneous squamous cell carcinoma to the axilla is uncommon, with limited data to guide management. We sought to assess the outcomes of patients with this condition after surgery and radiotherapy. METHODS: A retrospective cohort study of patients treated at two Australian hospitals from 1994 through 2016 was performed. RESULTS: A total of 74 patients were identified, including 48 treated curatively with surgery-plus-radiotherapy and 15 with surgery alone. Compared with patients treated with surgery alone, a higher proportion of patients treated with surgery-plus-radiotherapy had lymph nodes larger than 6 cm (53% versus 8%, P = 0.012) and multiple adverse histopathological features (75% versus 47%, P = 0.04). The groups had similar 5-year disease-free survival (45% versus 46%) and overall survival (51% versus 48%). Presence of multiple positive lymph nodes was associated with reduced disease-free survival (hazard ratio 4.57, P = 0.01) and overall survival (hazard ratio 3.53, P = 0.02). Regional recurrence was higher in patients treated with surgery alone (38% versus 22%, P = 0.22) and patients with lymph nodes larger than 6 cm (34% versus 10%, P = 0.03). All recurrences occurred within 2 years following treatment. CONCLUSION: Combined-modality therapy for metastatic cutaneous squamous cell carcinoma to the axilla is recommended for high-risk patients, although outcomes remain modest. The key period for recurrence is within 2 years following treatment.

Design and Testing of a Custom Melanoma Next Generation Sequencing Panel for Analysis of Circulating Tumor DNA.

Detection of melanoma-associated mutations using circulating tumor DNA (ctDNA) from plasma is a potential alternative to using genomic DNA from invasive tissue biopsies. In this study, we developed a custom melanoma next-generation sequencing (NGS) panel which includes 123 amplicons in 30 genes covering driver and targetable mutations and alterations associated with treatment resistance. Analysis of a cohort of 74 stage III and IV treatment-naïve melanoma patients revealed that sensitivity of ctDNA detection was influenced by the amount of circulating-free DNA (cfDNA) input and stage of melanoma. At the recommended cfDNA input quantity of 20 ng (available in 28/74 patients), at least one cancer-associated mutation was detected in the ctDNA of 84% of stage IV patients and 47% of stage III patients with a limit of detection for mutant allele frequency (MAF) of 0.2%. This custom melanoma panel showed significant correlation with droplet digital PCR (ddPCR) and provided a more comprehensive melanoma mutation profile. Our custom panel could be further optimized by replacing amplicons spanning the TERT promoter, which did not perform well due to the high GC content. To increase the detection rate to 90% of stage IV melanoma and decrease the sensitivity to 0.1% MAF, we recommend increasing the volume of plasma to 8 mL to achieve minimal recommended cfDNA input and the refinement of poorly performing amplicons. Our panel can also be expanded to include new targetable and treatment resistance mutations to improve the tracking of treatment response and resistance in melanoma patients treated with systemic drug therapies.

Sentinel lymph node biopsy in clinically node-negative Merkel cell carcinoma: the Westmead Hospital experience.

BACKGROUND: Merkel cell carcinoma (MCC) is a rare, aggressive cutaneous malignancy with a propensity to metastasize to regional lymph nodes. Sentinel lymph node biopsy (SLNB) in patients with clinically node-negative MCC has been utilized to identify patients with subclinical nodal metastases. This study aims to review the accuracy of SLNB in MCC and to evaluate the impact of SLNB on management. METHODS: Patients with clinically node-negative MCC who underwent SLNB were identified from a prospective database of patients treated at the Westmead Hospital, Sydney, between 1998 and 2017. Data from these patients were reviewed and analysed. RESULTS: Forty-one patients were identified: 28 men and 13 women, median age 70 years. Median duration of follow-up was 27 months. Sixteen (39%) patients had a positive SLNB and all underwent nodal treatment which consisted of radiotherapy (n = 13), completion lymphadenectomy and adjuvant radiotherapy (n = 2), and completion lymphadenectomy alone (n = 1). Following negative SLNB, 24 of 25 patients did not undergo further nodal treatment. The false-negative rate was 16% as three patients developed in-field nodal recurrence subsequent to a negative SLNB. At last follow-up, 29 patients had no evidence of disease, six were alive with disease and three had died from other causes. Three SLN-positive patients have died of MCC. CONCLUSION: SLNB has a high rate of positivity and can improve the accuracy of staging and prognostication in MCC, and guide management. The relatively low risk of a false-negative SLNB justifies close observation in SLNB-negative patients.

PD-L1 Expression and Immune Escape in Melanoma Resistance to MAPK Inhibitors.

Purpose: To examine the relationship between immune activity, PD-L1 expression, and tumor cell signaling, in metastatic melanomas prior to and during treatment with targeted MAPK inhibitors.Experimental Design: Thirty-eight tumors from 17 patients treated with BRAF inhibitor (n = 12) or combination BRAF/MEK inhibitors (n = 5) with known PD-L1 expression were analyzed. RNA expression arrays were performed on all pretreatment (PRE, n = 17), early during treatment (EDT, n = 8), and progression (PROG, n = 13) biopsies. HLA-A/HLA-DPB1 expression was assessed by IHC.Results: Gene set enrichment analysis (GSEA) of PRE, EDT, and PROG melanomas revealed that transcriptome signatures indicative of immune cell activation were strongly positively correlated with PD-L1 staining. In contrast, MAPK signaling and canonical Wnt/-ß-catenin activity was negatively associated with PD-L1 melanoma expression. The expression of PD-L1 and immune activation signatures did not simply reflect the degree or type of immune cell infiltration, and was not sufficient for tumor response to MAPK inhibition.Conclusions: PD-L1 expression correlates with immune cells and immune activity signatures in melanoma, but is not sufficient for tumor response to MAPK inhibition, as many PRE and PROG melanomas displayed both PD-L1 positivity and immune activation signatures. This confirms that immune escape is common in MAPK inhibitor-treated tumors. This has important implications for the selection of second-line immunotherapy because analysis of mechanisms of immune escape will likely be required to identify patients likely to respond to such therapies. Clin Cancer Res; 23(20); 6054-61. ©2017 AACR.

Definitive radiotherapy for Merkel cell carcinoma confers clinically meaningful in-field locoregional control: A review and analysis of the literature.

BACKGROUND: Merkel cell carcinoma (MCC) is an uncommon radiosensitive, neuroendocrine malignancy. Treatment often involves surgery; however, older, sicker patients may not be candidates for an operation. Institutions have published data favoring the role of definitive radiotherapy for macroscopic locoregional disease. OBJECTIVE: Our objective was to report the outcome of patients treated with definitive radiotherapy. METHODS: We performed a systematic review of Medline, PubMed, and Embase databases for reported cases or series of definitive radiotherapy for macroscopic locoregional MCC. RESULTS: The mean radiation dose did not significantly differ between primary and regional sites (48.7 ± 13.2 vs 49.4 ± 10.1 Gy, P = .74). The rate of recurrence was calculated on the basis of the site of disease (11.7%) and per patient (14.3%). Recurrence was significantly more likely to occur at regional than at primary irradiated sites (16.3% vs 7.6%, P = .02). There was no association between radiotherapy dose and incidence of recurrence or nonrecurrence; primary (42.7 ± 23 vs 49.3 ± 11.8 Gy, P = .197) and regional (48.6 ± 10 vs 49.5 ± 10.3 Gy, P = .77). LIMITATIONS: A limitation of this report is that most publications were retrospective; heterogeneity was present in the size of MCC and in radiotherapy details. CONCLUSIONS: Definitive radiotherapy for locoregional macroscopic MCC was found to confer clinically meaningful local and regional in-field control.

Dynamic Changes in PD-L1 Expression and Immune Infiltrates Early During Treatment Predict Response to PD-1 Blockade in Melanoma.

Purpose: Disruption of PD-L1/cytotoxic T-cell PD-1 signaling by immune checkpoint inhibitors improves survival in cancer patients. This study sought to identify changes in tumoral PD-L1 expression and tumor-associated immune cell flux with anti-PD-1 therapies in patients with melanoma, particularly early during treatment, and correlate them with treatment response.Experimental Design: Forty-six tumor biopsies from 23 patients with unresectable AJCC stage III/IV melanoma receiving pembrolizumab/nivolumab were analyzed. Biopsies were collected prior to (PRE, n = 21), within 2 months of commencing treatment (EDT, n = 20) and on disease progression after previous response (PROG, n = 5). Thirteen patients responded (defined as CR, PR, or durable SD by RECIST/irRC criteria), and 10 did not respond.Results: PRE intratumoral and peritumoral PD-1+ T-cell densities were sevenfold (P = 0.006) and fivefold higher (P = 0.011), respectively, in responders compared with nonresponders and correlated with degree of radiologic tumor response (r = -0.729, P = 0.001 and r = -0.725, P = 0.001, respectively). PRE PD-L1 expression on tumor and macrophages was not significantly different between the patient groups, but tumoral PD-L1 and macrophage PD-L1 expression was higher in the EDT of responders versus nonresponders (P = 0.025 and P = 0.033). Responder EDT biopsies (compared with PRE) also showed significant increases in intratumoral CD8+ lymphocytes (P = 0.046) and intratumoral CD68+ macrophages (P = 0.046).Conclusions: Higher PRE PD-1+ T cells in responders suggest active suppression of an engaged immune system that is disinhibited by anti-PD-1 therapies. Furthermore, immunoprofiling of EDT biopsies for increased PD-L1 expression and immune cell infiltration showed greater predictive utility than PRE biopsies and may allow better selection of patients most likely to benefit from anti-PD-1 therapies and warrants further evaluation. Clin Cancer Res; 23(17); 5024-33. ©2017 AACR.

Merkel cell carcinoma: A case of palliative upper limb amputation in a patient with refractory in-transit metastases.

We report an unusual case of Merkel cell carcinoma in a 70-year-old woman with the rapid development of left upper limb in-transit and hepatic metastases. The patient had a preceding history of left-sided breast cancer. Palliative chemotherapy with carboplatin and etoposide produced a minimal response. The in-transit metastases rapidly progressed and were refractory to chemotherapy and a single fraction of palliative radiotherapy, leading to a marked impact on her quality of life, secondary to sepsis and bleeding. After lengthy discussion, she consented to an above-elbow amputation resulting in a marked improvement in her well-being. In this case, we believe that palliative amputation of the involved arm was justified and beneficial to the patient.

Outcome of patients with microscopic and macroscopic metastatic nodal Merkel cell carcinoma: an Australian experience.

BACKGROUND: Merkel cell carcinoma (MCC) is an aggressive cutaneous malignancy with a high rate of nodal metastasis. The American Joint Committee on Cancer staging system subclassifies nodal disease into microscopic and macroscopic groups based on prognosis. OBJECTIVE: To compare the outcome of patients with microscopic and macroscopic nodal metastases. MATERIALS AND METHODS: Patients were identified from a database of 180 patients with MCC who presented to Westmead Hospital, Sydney, Australia, from 1980 to 2013. Disease-free survival (DFS), overall survival (OS), and follow-up were calculated using Kaplan-Meier curves and compared using the log-rank (Mantel-Cox) test. RESULTS: Forty-one patients were diagnosed with node-positive MCC; 11 patients had microscopic nodal metastases, with five (45%) relapsing, and 30 had macroscopic disease, with 17 (57%) relapsing. There was no significant difference in DFS (p = .93) or OS (p = .63) between the two groups. CONCLUSION: The nonsignificant difference in DFS and OS suggest that even microscopic nodal metastases can predict a poor outcome. Because more than half of patients subsequently relapse, often at a distant site, there is a need to develop an effective systemic treatment.

Intratumoral molecular heterogeneity in a BRAF-mutant, BRAF inhibitor-resistant melanoma: a case illustrating the challenges for personalized medicine.

Targeted therapies are increasingly being used to treat a variety of cancers. Their efficacy depends upon the accurate detection and targeting of a specific mutation or aberration in the tumor. All cancers, such as melanoma, are molecularly heterogeneous, with drug-resistant subclones present before the treatment or emerging as a result of targeted therapies. Here, we show intralesional molecular heterogeneity in a progressing V600E BRAF-mutant melanoma metastasis from a patient treated for 7 months with the BRAF inhibitor vemurafenib. In the single metastasis, two distinct subclones were observed, both V600E BRAF-mutant and only one with an additional G13R NRAS mutation. Molecular heterogeneity even at the intralesional level shows that personalizing or adjusting therapies based on genotyping of a portion of a single lesion may not accurately depict the molecular profile or drivers of oncogenesis across the entire patient's melanoma.

Distinguishing clinicopathologic features of patients with V600E and V600K BRAF-mutant metastatic melanoma.

PURPOSE: Certain clinicopathologic features correlate with BRAF mutation status in melanoma including younger age and primary subtype. This study sought to determine the BRAF mutation status by age-decade and whether BRAF-mutant genotypes correlated with clinicopathologic features and outcome in patients with metastatic melanoma. METHODS: A prospectively assembled cohort of Australian patients were followed from diagnosis of metastatic melanoma (N = 308). Clinicopathologic variables were correlated with BRAF mutational status, genotype, and survival. RESULTS: Forty-six percent of patients had a BRAF mutation; 73% V600E, 19% V600K, and 8% other genotypes. An inverse relationship existed between BRAF mutation prevalence and age-decade (P < 0.001). All patients <30 years and only 25% ≥ 70 years had BRAF-mutant melanoma. Amongst BRAF-mutant melanoma, the frequency of non-V600E genotypes (including V600K) increased with increasing age. Non-V600E genotypes comprised <20% in patients <50 years and >40% in those ≥ 70 years. A higher degree of cumulative sun-induced damage correlated with V600K but not V600E melanoma (P = 0.002). The disease-free interval from diagnosis of primary melanoma to first distant metastasis was shorter for patients with V600K compared with V600E melanoma (17.4 vs. 39.2 months, P = 0.048), with no difference in survival thereafter. In patients BRAF tested at diagnosis of metastatic melanoma, one year survival from diagnosis of metastasis was significantly longer for patients with BRAF-mutant melanoma treated with an inhibitor (83%), than those not treated with an inhibitor (29%, P < 0.001), or patients with BRAF wild-type melanoma (37%, P < 0.001). CONCLUSION: Different genotypes exist within BRAF-mutant metastatic melanoma, representing biologically and clinically discrete subtypes, suggesting distinct etiology and behavior.

Merkel cell carcinoma: an Australian perspective and the importance of addressing the regional lymph nodes in clinically node-negative patients.

BACKGROUND: Merkel cell carcinoma (MCC) is a rare, aggressive cutaneous malignancy. Nodal status has prognostic significance. OBJECTIVE: We sought to analyze for factors predictive of survival and explore the significance of lymph node status and indication for sentinel lymph node biopsy in patients with MCC. METHODS: A review was undertaken of 136 patients presenting with MCC at our institution between 1980 and 2008. Patient and tumor characteristics, treatment, and patterns of relapse were analyzed. RESULTS: Ninety patients presented with stage I disease, and 46 presented with stage II disease. The median follow-up time was 21 months. In all, 74 patients developed relapse with the commonest site of relapse in the regional lymph nodes. A total of 24 patients developed nodal relapse without prior treatment of the nodal basin. The 5-year survival was 62% and the median disease-free interval was 16 months. Radiotherapy was associated with a better disease-free survival (P < .001) and overall survival was worse as the number of involved lymph nodes increased (P = .03). LIMITATIONS: This was a retrospective review with a prolonged accrual time. CONCLUSION: A high rate of nodal relapse occurred in patients with stage I disease who had undergone treatment of the primary site only. These patients may have benefited from sentinel lymph node biopsy and subsequent treatment of the nodal basin if micrometastatic disease was present, as the number of involved nodes impacted negatively on survival. Conversely, sentinel lymph node biopsy may be used to select those patients with clinical stage I disease who may avoid elective nodal treatment. Radiotherapy should have a routine role in the management of MCC.

Selective BRAF inhibitors induce marked T-cell infiltration into human metastatic melanoma.

PURPOSE: To evaluate the effects of treatment with the potent mutant BRAF inhibitors GSK2118436 or vemurafenib (PLX4720) on immune responses to metastatic melanoma in tissues taken before and after treatment. EXPERIMENTAL DESIGN: Thirty-seven tumor biopsies were collected from 15 patients with unresectable American Joint Committee on Cancer stage III or IV melanoma immediately before and approximately 7 days after the commencement of BRAF inhibitor treatment and at the time of tumor progression. Immunohistochemical staining was carried out on the biopsies using specific antibodies for CD8, CD4, CD20, CD1a, and Granzyme B. RESULTS: Tumor infiltration by CD4(+) and CD8(+) lymphocytes increased markedly following BRAF inhibitor treatment (both ρ = 0.015). There was a correlation between the degree of tumor infiltration by CD8(+) and Granzyme B-expressing lymphocytes in post-BRAF inhibitor-treated biopsies (r = 0.690 and ρ = 0.013). Increased intratumoral CD8(+) lymphocyte expression was correlated with a reduction in tumor size and an increase in necrosis in posttreatment biopsies (r = -0.793, ρ = 0.011; and r = 0.761, ρ = 0.004, respectively). CONCLUSIONS: The increase in tumor-infiltrating lymphocytes induced by treatment with BRAF inhibitors provides strong support for conducting trials that combine BRAF inhibitors with immunotherapy in the hope of prolonging clinical responses.