Five-year analysis of neoadjuvant dabrafenib and trametinib for stage III melanoma.

BACKGROUND: Neoadjuvant dabrafenib plus trametinib has a high pathological response rate and impressive short-term survival in patients with resectable stage III melanoma. We report 5-year outcomes from the phase II NeoCombi trial. PATIENTS AND METHODS: NeoCombi (NCT01972347) was a single-arm, open-label, single-centre, phase II trial. Eligible patients were adults (aged ≥18 years) with histologically confirmed, resectable, RECIST-measurable, American Joint Committee on Cancer seventh edition clinical stage IIIB-C BRAF V600E/K-mutant melanoma and Eastern Cooperative Oncology Group performance status ≤1. Patients received 52 weeks of treatment with dabrafenib 150 mg (orally twice per day) plus trametinib 2 mg (orally once per day), with complete resection of the pre-therapy tumour bed at week 12. RESULTS: Between 20 August 2014 and 19 April 2017, 35 patients were enrolled. At data cut-off (17 August 2021), the median follow-up was 60 months [95% confidence interval (CI) 56-72 months]. Overall, 21 of 35 (60%) patients recurred, including 12 (57%) with first recurrence in locoregional sites (followed by later distant recurrence in 6) and 9 (43%) with first recurrence in distant sites, including 3 in the brain. Most recurrences occurred within 2 years, with no recurrences beyond 3 years. At 5 years, recurrence-free survival (RFS) was 40% (95% CI 27% to 60%), distant metastasis-free survival (DMFS) was 57% (95% CI 42% to 76%), and overall survival was 80% (95% CI 67% to 94%). Five-year survival outcomes were stratified by pathological response: RFS was 53% with pathological complete response (pCR) versus 28% with non-pCR (P = 0.087), DMFS was 59% versus 55% (P = 0.647), and overall survival was 88% versus 71% (P = 0.205), respectively. CONCLUSIONS: Neoadjuvant dabrafenib plus trametinib has high pathological response rates in clinical stage III melanoma, but low rates of RFS, similar to those achieved with adjuvant targeted therapy alone. Patients with a pCR to dabrafenib plus trametinib still had a high risk of recurrence, unlike that seen with immunotherapy where recurrences are rare.

Phase II clinical trial of neoadjuvant anti-PD-1 (toripalimab) combined with axitinib in resectable mucosal melanoma.

BACKGROUND: The outcome of patients with resectable mucosal melanoma is poor. Toripalimab combined with axitinib has shown impressive results in metastatic mucosal melanoma with an objective response rate of 48.3% and a median progression-free survival of 7.5 months in a phase Ib trial. It was hypothesized that this combination administered in the neoadjuvant setting might induce a pathologic response in resectable mucosal melanoma, so we conducted this trial. PATIENTS AND METHODS: This single-arm phase II trial enrolled patients with resectable mucosal melanoma. Patients received toripalimab 3 mg/kg once every 2 weeks (Q2W) plus axitinib 5 mg two times a day (b.i.d.) for 8 weeks as neoadjuvant therapy, then surgery and adjuvant toripalimab 3 mg/kg Q2W starting 2 ± 1weeks after surgery for 44 weeks. The primary endpoint was the pathologic response rate according to the International Neoadjuvant Melanoma Consortium recommendations. RESULTS: Between August 2019 and October 2021, 29 patients were enrolled and received treatment, of whom 24 underwent resection. The median follow-up time was 34.2 months (95% confidence interval 20.4-48.0 months). The pathologic response rate was 33.3% (8/24; 4 pathological complete responses and 4 pathological partial responses). The median event-free survival for all patients was 11.1 months (95% confidence interval 5.3-16.9 months). The median overall survival was not reached. Neoadjuvant therapy was tolerable with 8 (27.5%) grade 3-4 treatment-related adverse events and no treatment-related deaths. Tissue samples of 17 patients at baseline and after surgery were collected (5 responders and 12 nonresponders). Multiplex immunohistochemistry demonstrated a significant increase in CD3+ (P = 0.0032) and CD3+CD8+ (P = 0.0038) tumor-infiltrating lymphocytes after neoadjuvant therapy, particularly in pathological responders. CONCLUSIONS: Neoadjuvant toripalimab combined with axitinib in resectable mucosal melanoma demonstrated a promising pathologic response rate with significantly increased infiltrating CD3+ and CD3+CD8+ T cells after therapy.

Immune checkpoint inhibitor-induced neurotoxicity is not associated with seroprevalence of neurotropic infections.

BACKGROUND: Immune checkpoint inhibitors (ICI) substantially improve outcome for patients with cancer. However, the majority of patients develops immune-related adverse events (irAEs), which can be persistent and significantly reduce quality of life. Neurological irAEs occur in 1-5% of patients and can induce severe, permanent sequelae or even be fatal. In order to improve the diagnosis and treatment of neurological irAEs and to better understand their pathogenesis, we assessed whether previous neurotropic infections are associated with neurological irAEs. METHODS: Neurotropic infections that might predispose to ICI-induced neurological irAEs were analyzed in 61 melanoma patients from 3 countries, the Netherlands, Australia and Germany, including 24 patients with neurotoxicity and 37 control patients. In total, 14 viral, 6 bacterial, and 1 protozoal infections previously reported to trigger neurological pathologies were assessed using routine serology testing. The Dutch and Australian cohorts (NL) included pre-treatment plasma samples of patients treated with neoadjuvant ICI therapy (OpACIN-neo and PRADO trials; NCT02977052). In the Dutch/Australian cohort a total of 11 patients with neurological irAEs were compared to 27 control patients (patients without neurological irAEs). The German cohort (LMU) consisted of serum samples of 13 patients with neurological irAE and 10 control patients without any documented irAE under ICI therapy. RESULTS: The association of neurological irAEs with 21 possible preceding infections was assessed by measuring specific antibodies against investigated agents. The seroprevalence of all the tested viral (cytomegalovirus, Epstein-Barr-Virus, varicella-zoster virus, measles, rubella, influenza A and B, human herpes virus 6 and 7, herpes simplex virus 1 and 2, parvovirus B19, hepatitis A and E and human T-lymphotropic virus type 1 and 2), bacterial (Borrelia burgdorferi sensu lato, Campylobacter jejuni, Mycoplasma pneumoniae, Coxiella burnetti, Helicobacter pylori, Yersinia enterocolitica and Y. pseudotuberculosis) and protozoal (Toxoplasma gondii) infections was similar for patients who developed neurological irAEs as compared to control patients. Thus, the analysis provided no evidence for an association of described agents tested for seroprevalence with ICI induced neurotoxicity. CONCLUSION: Previous viral, bacterial and protozoal neurotropic infections appear not to be associated with the development of neurological irAEs in melanoma patients who underwent therapy with ICI across 3 countries. Further efforts are needed to unravel the factors underlying neurological irAEs in order to identify risk factors for these toxicities, especially with the increasing use of ICI in earlier stage disease.

Efficacy of immune checkpoint inhibitors for the treatment of advanced melanoma in patients with concomitant chronic lymphocytic leukemia.

BACKGROUND: Immune checkpoint inhibitors (ICIs) have revolutionized the management of advanced melanoma (AM). However, data on ICI effectiveness have largely been restricted to clinical trials, thereby excluding patients with co-existing malignancies. Chronic lymphocytic leukemia (CLL) is the most prevalent adult leukemia and is associated with increased risk of melanoma. CLL alters systemic immunity and can induce T-cell exhaustion, which may limit the efficacy of ICIs in patients with CLL. We, therefore, sought to examine the efficacy of ICI in patients with these co-occurring diagnoses. PATIENTS AND METHODS: In this international multicenter study, a retrospective review of clinical databases identified patients with concomitant diagnoses of CLL and AM treated with ICI (US-MD Anderson Cancer Center, N = 24; US-Mayo Clinic, N = 15; AUS, N = 19). Objective response rates (ORRs), assessed by RECIST v1.1, and survival outcomes [overall survival (OS) and progression-free survival (PFS)] among patients with CLL and AM were assessed. Clinical factors associated with improved ORR and survival were explored. Additionally, ORR and survival outcomes were compared between the Australian CLL/AM cohort and a control cohort of 148 Australian patients with AM alone. RESULTS: Between 1997 and 2020, 58 patients with concomitant CLL and AM were treated with ICI. ORRs were comparable between AUS-CLL/AM and AM control cohorts (53% versus 48%, P = 0.81). PFS and OS from ICI initiation were also comparable between cohorts. Among CLL/AM patients, a majority were untreated for their CLL (64%) at the time of ICI. Patients with prior history of chemoimmunotherapy treatment for CLL (19%) had significantly reduced ORRs, PFS, and OS. CONCLUSIONS: Our case series of patients with concomitant CLL and melanoma demonstrate frequent, durable clinical responses to ICI. However, those with prior chemoimmunotherapy treatment for CLL had significantly worse outcomes. We found that CLL disease course is largely unchanged by treatment with ICI.

Survival update of neoadjuvant ipilimumab plus nivolumab in macroscopic stage III melanoma in the OpACIN and OpACIN-neo trials.

BACKGROUND: Neoadjuvant ipilimumab plus nivolumab has yielded high response rates in patients with macroscopic stage III melanoma. These response rates translated to high short-term survival rates. However, data on long-term survival and disease recurrence are lacking. PATIENTS AND METHODS: In OpACIN, 20 patients with macroscopic stage III melanoma were randomized to ipilimumab 3 mg/kg plus nivolumab 1 mg/kg q3w four cycles of adjuvant or split two cycles of neoadjuvant and two adjuvant. In OpACIN-neo, 86 patients with macroscopic stage III melanoma were randomized to arm A (2× ipilimumab 3 mg/kg plus nivolumab 1 mg/kg q3w; n = 30), arm B (2× ipilimumab 1 mg/kg plus nivolumab 3 mg/kg q3w; n = 30), or arm C (2× ipilimumab 3 mg/kg q3w plus 2× nivolumab 3 mg/kg q2w; n = 26) followed by surgery. RESULTS: The median recurrence-free survival (RFS) and overall survival (OS) were not reached in either trial. After a median follow-up of 69 months for OpACIN, 1/7 patients with a pathologic response to neoadjuvant therapy had disease recurrence. The estimated 5-year RFS and OS rates for the neoadjuvant arm were 70% and 90% versus 60% and 70% for the adjuvant arm. After a median follow-up of 47 months for OpACIN-neo, the estimated 3-year RFS and OS rates were 82% and 92%, respectively. The estimated 3-year RFS rate for OpACIN-neo was 95% for patients with a pathologic response versus 37% for patients without a pathologic response (P < 0.001). In multiple regression analyses, pathologic response was the strongest predictor of disease recurrence. Of the 12 patients with distant disease recurrence after neoadjuvant therapy, 5 responded to subsequent anti-PD-1 and 8 to targeted therapy, although 7 patients showed progression after the initial response. CONCLUSIONS: Updated data confirm the high survival rates after neoadjuvant combination checkpoint inhibition in macroscopic stage III melanoma, especially for patients with a pathologic response. Pathologic response is the strongest surrogate marker for long-term outcome.

Single-agent anti-PD-1 or combined with ipilimumab in patients with mucosal melanoma: an international, retrospective, cohort study.

BACKGROUND: Mucosal melanoma (MM) is a rare melanoma subtype with distinct biology and poor prognosis. Data on the efficacy of immune checkpoint inhibitors (ICIs) are limited. We determined the efficacy of ICIs in MM, analyzed by primary site and ethnicity/race. PATIENTS AND METHODS: A retrospective cohort study from 25 cancer centers in Australia, Europe, USA and Asia was carried out. Patients with histologically confirmed MM were treated with anti-programmed cell death protein 1 (PD-1) ± ipilimumab. Primary endpoints were response rate (RR), progression-free survival (PFS), overall survival (OS) by primary site (naso-oral, urogenital, anorectal, other), ethnicity/race (Caucasian, Asian, Other) and treatment. Univariate and multivariate Cox proportional hazards model analyses were conducted. RESULTS: In total, 545 patients were included: 331 (63%) Caucasian, 176 (33%) Asian and 20 (4%) Other. Primary sites included 113 (21%) anorectal, 178 (32%) urogenital, 206 (38%) naso-oral and 45 (8%) other. Three hundred and forty-eight (64%) patients received anti-PD-1 and 197 (36%) anti-PD-1/ipilimumab. RR, PFS and OS did not differ by primary site, ethnicity/race or treatment. RR for naso-oral was numerically higher for anti-PD-1/ipilimumab [40%, 95% confidence interval (CI) 29% to 54%] compared with anti-PD-1 (29%, 95% CI 21% to 37%). Thirty-five percent of patients who initially responded progressed. The median duration of response (mDoR) was 26 months (95% CI 18 months-not reached). Factors associated with short PFS were Eastern Cooperative Oncology Group (ECOG) performance status (PS) ≥3 (P < 0.01), lactate dehydrogenase (LDH) more than the upper limit of normal (ULN) (P = 0.01), lung metastases (P < 0.01) and ≥1 previous treatments (P < 0.01). Factors associated with short OS were ECOG PS ≥1 (P < 0.01), LDH >ULN (P = 0.03), lung metastases (P < 0.01) and ≥1 previous treatments (P < 0.01). CONCLUSIONS: MM has poor prognosis. Treatment efficacy of anti-PD-1 ± ipilimumab was similar and did not differ by ethnicity/race. Naso-oral primaries had numerically higher response to anti-PD-1/ipilimumab, without difference in survival. The addition of ipilimumab did not show greater benefit over anti-PD-1 for other primary sites. In responders, mDoR was short and acquired resistance was common. Other factors, including site and number of metastases, were associated with survival.

FDG-PET to predict long-term outcome from anti-PD-1 therapy in metastatic melanoma.

BACKGROUND: We have previously shown that 75% of patients treated with programmed cell death protein 1 (PD-1) with or without CTLA4 who have not progressed by 1 year have complete metabolic response (CMR), including two-thirds of patients with partial response (PR). We now report 5-year outcomes. PATIENTS AND METHODS: Retrospective analysis of 104 patients with baseline and 1-year positron emission tomography (PET) and computed tomography (CT). The 1-year response was determined using RECIST for CT and European Organisation for Research and Treatment of Cancer (EORTC) criteria for PET. Progression-free survival (PFS) and overall survival (OS) were determined from the 1-year landmark. RESULTS: At the median follow-up of 61 months (range 58-64 months) from 1-year PET, 94% remained alive and all but one had discontinued treatment after a median treatment duration of 23 months (range 1-59 months). Disease progression occurred in 19 patients (18%): 10 (53%) while on treatment and 12 (63%) in solitary sites for which 8 (67%) received local treatment. RECIST PFS rate at 5 years after PET was higher in complete response (CR) compared with PR/stable disease (SD) (93% versus 76%, respectively) and CMR compared with non-CMR (90% versus 54%, respectively). In patients with PR, 5-year PFS rate was superior in CMR (88% and 59%). A total of 35 (34%) patients (14/29 in CR, 31/78 in CMR) discontinued treatment within 12 months, largely due to toxicity, with no impact on PFS rate compared with those that continued (84% versus 78%). Despite progression events, OS rate at 5 years was excellent and similar in patients with CR and PR/SD (100% versus 91%, respectively) as well as in those with CMR and non-CMR (96% versus 87%, respectively). CONCLUSIONS: Five years after the 1-year PET, sustained responses are observed in the majority of patients, particularly in those with CMR. PET continues to predict progression better than CT, particularly in those with residual disease on CT. In the minority that progress, often in solitary sites and managed locally, OS rate remains excellent. PET is effective in evaluating residual lesions on CT and can predict long-term benefit.

Antitumor activity of ipilimumab or BRAF ± MEK inhibition after pembrolizumab treatment in patients with advanced melanoma: analysis from KEYNOTE-006.

BACKGROUND: Antitumor activity of ipilimumab or BRAF ± MEK inhibitors (BRAFi ± MEKi) following pembrolizumab administration in melanoma is poorly characterized. PATIENTS AND METHODS: In the phase III KEYNOTE-006 study, patients with unresectable stage III/IV melanoma received pembrolizumab (10 mg/kg) once every 2 or 3 weeks (Q3W) or ipilimumab (3 mg/kg) Q3W. The current post hoc analysis evaluates outcomes with ipilimumab or BRAFi ± MEKi as first subsequent systemic therapy after pembrolizumab administration and includes patients who completed or discontinued pembrolizumab after one or more dose. Pembrolizumab arms were pooled. RESULTS: At data cut-off (4 December 2017), median follow-up was 46.9 months. Of 555 pembrolizumab-treated patients, first subsequent therapy was ipilimumab for 103 (18.6%) and BRAFi ± MEKi for 59 (10.6%) [33 received BRAFi + MEKi, 26 BRAFi alone; 37 (62.7%) were BRAFi ± MEKi naïve]. In the subsequent ipilimumab group, ORR with previous pembrolizumab was 17.5% [1 complete response (CR); 17 partial response (PR)]; 79.6% had discontinued pembrolizumab due to progressive disease (PD); median overall survival (OS) was 21.5 months. ORR with subsequent ipilimumab was 15.5%; 11/16 responses (8 CRs; 3 PRs) were ongoing. ORR with subsequent ipilimumab was 9.7% for patients with PD as best response to pembrolizumab. Median OS from ipilimumab initiation was 9.8 months. In the subsequent BRAFi ± MEKi group, ORR with previous pembrolizumab was 13.5% (8 PR); 76.3% had discontinued pembrolizumab due to PD; median OS was 17.9 months. ORR with subsequent BRAFi ± MEKi was 30.5%, 7/18 responses (4 CR, 3 PR) were ongoing. Median OS from BRAFi ± MEKi initiation was 12.9 months. ORR for BRAFi ± MEKi-naïve patients who received subsequent BRAFi ± MEKi was 43.2%; 6/16 were ongoing (3 CR, 3 PR). CONCLUSIONS: Ipilimumab and BRAFi ± MEKi have antitumor activity as first subsequent therapy after pembrolizumab in patients with advanced melanoma.

Acute bilateral phrenic nerve neuropathy causing hypercapnic respiratory associated with checkpoint inhibitor immunotherapy.

We present two cases of acute hypercapnic respiratory failure due to diaphragmatic dysfunction secondary to bilateral phrenic nerve paralysis, in patients who were receiving immunotherapy for melanoma. Bilateral diaphragmatic paralysis is an uncommon cause of acute or sub-acute hypercapnic respiratory failure which causes severe breathlessness, orthopnoea and potentially death. Immune checkpoint inhibitors are now standard of care in several solid organ malignancies. However, their use is associated with a risk of developing autoimmune toxicities, which includes mononeuritis. Our two cases demonstrate the potential difficulties in recognising acute hypercapnic respiratory failure and diagnosis of the rare disorder of bilateral diaphragmatic dysfunction, with consequent delays in appropriate management. The occurrence of this rare condition in association with checkpoint inhibitor immunotherapy suggests a possible autoimmune mechanism. Awareness that this rare cause of respiratory failure may occur in patients receiving checkpoint inhibitor therapy might facilitate earlier diagnosis and treatment.

Delayed immune-related adverse events with anti-PD-1-based immunotherapy in melanoma.

BACKGROUND: Immune-related adverse events (irAEs) typically occur within 4 months of starting anti-programmed cell death protein 1 (PD-1)-based therapy [anti-PD-1 ± anti-cytotoxic T-lymphocyte-associated protein 4 (CTLA4)], but delayed irAEs (onset >12 months after commencement) can also occur. This study describes the incidence, nature and management of delayed irAEs in patients receiving anti-PD-1-based immunotherapy. PATIENTS AND METHODS: Patients with delayed irAEs from 20 centres were studied. The incidence of delayed irAEs was estimated as a proportion of melanoma patients treated with anti-PD-1-based therapy and surviving >1 year. Onset, clinical features, management and outcomes of irAEs were examined. RESULTS: One hundred and eighteen patients developed a total of 140 delayed irAEs (20 after initial combination with anti-CTLA4), with an estimated incidence of 5.3% (95% confidence interval 4.0-6.9, 53/999 patients at sites with available data). The median onset of delayed irAE was 16 months (range 12-53 months). Eighty-seven patients (74%) were on anti-PD-1 at irAE onset, 15 patients (12%) were <3 months from the last dose and 16 patients (14%) were >3 months from the last dose of anti-PD-1. The most common delayed irAEs were colitis, rash and pneumonitis; 55 of all irAEs (39%) were ≥grade 3. Steroids were required in 80 patients (68%), as well as an additional immunosuppressive agent in 27 patients (23%). There were two irAE-related deaths: encephalitis with onset during anti-PD-1 and a multiple-organ irAE with onset 11 months after ceasing anti-PD-1. Early irAEs (<12 months) had also occurred in 69 patients (58%), affecting a different organ from the delayed irAE in 59 patients (86%). CONCLUSIONS: Delayed irAEs occur in a small but relevant subset of patients. Delayed irAEs are often different from previous irAEs, may be high grade and can lead to death. They mostly occur in patients still receiving anti-PD-1. The risk of delayed irAE should be considered when deciding the duration of treatment in responding patients. However, patients who stop treatment may also rarely develop delayed irAE.

Pathological response and tumour bed histopathological features correlate with survival following neoadjuvant immunotherapy in stage III melanoma.

BACKGROUND: Guidelines for pathological evaluation of neoadjuvant specimens and pathological response categories have been developed by the International Neoadjuvant Melanoma Consortium (INMC). As part of the Optimal Neo-adjuvant Combination Scheme of Ipilimumab and Nivolumab (OpACIN-neo) clinical trial of neoadjuvant combination anti-programmed cell death protein 1/anti-cytotoxic T-lymphocyte-associated protein 4 immunotherapy for stage III melanoma, we sought to determine interobserver reproducibility of INMC histopathological assessment principles, identify specific tumour bed histopathological features of immunotherapeutic response that correlated with recurrence and relapse-free survival (RFS) and evaluate proposed INMC pathological response categories for predicting recurrence and RFS. PATIENTS AND METHODS: Clinicopathological characteristics of lymph node dissection specimens of 83 patients enrolled in the OpACIN-neo clinical trial were evaluated. Two methods of assessing histological features of immunotherapeutic response were evaluated: the previously described immune-related pathologic response (irPR) score and our novel immunotherapeutic response score (ITRS). For a subset of cases (n = 29), cellular composition of the tumour bed was analysed by flow cytometry. RESULTS: There was strong interobserver reproducibility in assessment of pathological response (κ = 0.879) and percentage residual viable melanoma (intraclass correlation coefficient = 0.965). The immunotherapeutic response subtype with high fibrosis had the strongest association with lack of recurrence (P = 0.008) and prolonged RFS (P = 0.019). Amongst patients with criteria for pathological non-response (pNR, >50% viable tumour), all who recurred had ≥70% viable melanoma. Higher ITRS and irPR scores correlated with lack of recurrence in the entire cohort (P = 0.002 and P ≤ 0.0001). The number of B lymphocytes was significantly increased in patients with a high fibrosis subtype of treatment response (P = 0.046). CONCLUSIONS: There is strong reproducibility for assessment of pathological response using INMC criteria. Immunotherapeutic response of fibrosis subtype correlated with improved RFS, and may represent a biomarker. Potential B-cell contribution to fibrosis development warrants further study. Reclassification of pNR to a threshold of ≥70% viable melanoma and incorporating additional criteria of <10% fibrosis subtype of response may identify those at highest risk of recurrence, but requires validation.

Novel adjuvant options for cutaneous melanoma.

BACKGROUND: Patients with resected stage III and IV melanoma have a high risk of recurrence. As the outcomes for patients with metastatic disease have improved dramatically over the past decade due to systemic therapy, more recently so too have the outcomes of patients with resected stage III and IV melanoma with the introduction of checkpoint inhibitor immunotherapy and targeted therapy in the adjuvant setting. MATERIALS AND METHODS: This review outlines the latest clinical trial data, the current adjuvant treatment landscape and its application to clinical practice and expected future progress for the management of early-stage melanoma. RESULTS: Anti-programmed cell death protein 1 monotherapy and BRAF/MEK inhibitors are currently deemed standard of care for resected stage III melanoma. For patients with stage IIIB [American Joint Committee on Cancer staging system version 7 (AJCCv7)] melanoma, 2-year and 3-year recurrence-free survival is approximately 72% and 65% for nivolumab, 70% and 65.7% for pembrolizumab and 68% and 60% for dabrafenib/trametinib, respectively. For stage IIIC (AJCCv7) melanoma, 2-year and 3-year recurrence-free survival is 60% and 53.5% for nivolumab, 60% and 54.3% for pembrolizumab and 59% and 47% for dabrafenib/trametinib, respectively. Adjuvant treatment is recommended for patients with stage IIIB-IIID [AJCC staging system version 8 (AJCCv8)] melanoma, and may be considered for patients with stage IIIA melanoma. For resected stage IV, nivolumab is the only approved agent; however, recent results from a phase II clinical trial show promising efficacy for combined ipilimumab and nivolumab as well. Long-term data are required to determine which therapy has the greatest impact on overall survival. Schedules, delivery and toxicity are also important factors to consider when selecting adjuvant treatment. CONCLUSIONS: Randomized studies of patients with resected high-risk melanoma have shown that immunotherapy or targeted therapy improve recurrence-free survival compared with placebo/ipilimumab. In order to optimize these treatments, prognostic and predictive biomarkers, as well as strategies to reduce treatment-related toxicities and overcome resistance, are required.

Survival and biomarker analyses from the OpACIN-neo and OpACIN neoadjuvant immunotherapy trials in stage III melanoma.

Neoadjuvant ipilimumab plus nivolumab showed high pathologic response rates (pRRs) in patients with macroscopic stage III melanoma in the phase 1b OpACIN ( NCT02437279 ) and phase 2 OpACIN-neo ( NCT02977052 ) studies1,2. While the results are promising, data on the durability of these pathologic responses and baseline biomarkers for response and survival were lacking. After a median follow-up of 4 years, none of the patients with a pathologic response (n = 7/9 patients) in the OpACIN study had relapsed. In OpACIN-neo (n = 86), the 2-year estimated relapse-free survival was 84% for all patients, 97% for patients achieving a pathologic response and 36% for nonresponders (P < 0.001). High tumor mutational burden (TMB) and high interferon-gamma-related gene expression signature score (IFN-γ score) were associated with pathologic response and low risk of relapse; pRR was 100% in patients with high IFN-γ score/high TMB; patients with high IFN-γ score/low TMB or low IFN-γ score/high TMB had pRRs of 91% and 88%; while patients with low IFN-γ score/low TMB had a pRR of only 39%. These data demonstrate long-term benefit in patients with a pathologic response and show the predictive potential of TMB and IFN-γ score. Our findings provide a strong rationale for a randomized phase 3 study comparing neoadjuvant ipilimumab plus nivolumab versus standard adjuvant therapy with antibodies against the programmed cell death protein-1 (anti-PD-1) in macroscopic stage III melanoma.

Mucosal-associated invariant T (MAIT) cells are activated in the gastrointestinal tissue of patients with combination ipilimumab and nivolumab therapy-related colitis in a pathology distinct from ulcerative colitis.

The aim of this study was to investigate the pathogenesis of combination ipilimumab and nivolumab-associated colitis (IN-COL) by measuring gut-derived and peripheral blood mononuclear cell (GMNC; PBMC) profiles. We studied GMNC and PBMC from patients with IN-COL, IN-treated with no adverse-events (IN-NAE), ulcerative colitis (UC) and healthy volunteers using flow cytometry. In the gastrointestinal-derived cells we found high levels of activated CD8+ T cells and mucosal-associated invariant T (MAIT) cells in IN-COL, changes that were not evident in IN-NAE or UC. UC, but not IN-C, was associated with a high proportion of regulatory T cells (Treg ). We sought to determine if local tissue responses could be measured in peripheral blood. Peripherally, checkpoint inhibition instigated a rise in activated memory CD4+ and CD8+ T cells, regardless of colitis. Low circulating MAIT cells at baseline was associated with IN-COL patients compared with IN-NAE in one of two cohorts. UC, but not IN-COL, was associated with high levels of circulating plasmablasts. In summary, the alterations in T cell subsets measured in IN-COL-affected tissue, characterized by high levels of activated CD8+ T cells and MAIT cells and a low proportion of Treg , reflected a pathology distinct from UC. These tissue changes differed from the periphery, where T cell activation was a widespread on-treatment effect, and circulating MAIT cell count was low but not reliably predictive of colitis.

Histopathological features of complete pathological response predict recurrence-free survival following neoadjuvant targeted therapy for metastatic melanoma.

BACKGROUND: Recent clinical trials demonstrated the safety and efficacy of neoadjuvant dabrafenib and trametinib (DT) among patients with surgically resectable clinical stage III BRAFV600E/K mutant melanoma. Although patients achieving a complete pathological response (pCR) exhibited superior recurrence-free survival (RFS) versus those who did not, 30% of pCR patients relapsed. We sought to identify whether histopathological features of the pathological response further delineated risk of relapse. METHODS: Surgical resection specimens from DT-treated patients in two phase 2 clinical trials were reviewed. Histopathological features, including relative amounts of viable tumour, necrosis, melanosis, and fibrosis (hyalinized or immature/proliferative) were assessed for associations with patient outcomes. RESULTS: Fifty-nine patients underwent surgical resection following neoadjuvant DT. Patients achieving pCR (49%) had longer RFS compared with patients who did not (P = 0.005). Patients whose treated tumour showed any hyalinized fibrosis had longer RFS versus those without (P = 0.014), whereas necrosis (P = 0.012) and/or immature/proliferative fibrosis (P = 0.026) correlated with shorter RFS. Multivariable analyses showed absence of pCR or presence of immature fibrosis independently predicted shorter RFS. Among pCR patients, mature/hyalinized-type fibrosis correlated with improved RFS (P = 0.035). CONCLUSIONS: The extent and composition of the pathological response following neoadjuvant DT in BRAFV600E/K mutant melanoma correlates with RFS, including pCR patients. These findings support the need for detailed histological analysis of specimens collected after neoadjuvant therapy.

Management of early melanoma recurrence despite adjuvant anti-PD-1 antibody therapy☆.

BACKGROUND: Anti-programmed cell death protein 1 (PD-1) antibodies (PD1) prolong recurrence-free survival in high-risk resected melanoma; however, approximately 25%-30% of patients recur within 1 year. This study describes the pattern of recurrence, management and outcomes of patients who recur with adjuvant PD1 therapy. PATIENTS AND METHODS: Consecutive patients from 16 centres who recurred having received adjuvant PD1 therapy for resected stage III/IV melanoma were studied. Recurrence characteristics, management and outcomes were examined; patients with mucosal melanoma were analysed separately. RESULTS: Melanoma recurrence occurred in 147 (17%) of ∼850 patients treated with adjuvant PD1. In those with cutaneous melanoma (n = 136), median time to recurrence was 4.6 months (range 0.3-35.7); 104 (76%) recurred during (ON) adjuvant PD1 after a median 3.2 months and 32 (24%) following (OFF) treatment cessation after a median 12.5 months, including in 21 (15%) who ceased early for toxicity. Fifty-nine (43%) recurred with locoregional disease only and 77 (57%) with distant disease. Of those who recurred locally, 22/59 (37%) subsequently recurred distantly. Eighty-nine (65%) patients received systemic therapy after recurrence. Of those who recurred ON adjuvant PD1, none (0/6) responded to PD1 alone; 8/33 assessable patients (24%) responded to ipilimumab (alone or in combination with PD1) and 18/23 (78%) responded to BRAF/MEK inhibitors. Of those who recurred OFF adjuvant PD1, two out of five (40%) responded to PD1 monotherapy, two out of five (40%) responded to ipilimumab-based therapy and 9/10 (90%) responded to BRAF/MEK inhibitors. CONCLUSIONS: Most patients who recur early despite adjuvant PD1 develop distant metastases. In those who recur ON adjuvant PD1, there is minimal activity of further PD1 monotherapy, but ipilimumab (alone or in combination with PD1) and BRAF/MEK inhibitors have clinical utility. Retreatment with PD1 may have activity in select patients who recur OFF PD1.

External validation of a prognostic model to predict survival of patients with sentinel node-negative melanoma.

BACKGROUND: Identifying patients with sentinel node-negative melanoma at high risk of recurrence or death is important. The European Organisation for Research and Treatment of Cancer (EORTC) recently developed a prognostic model including Breslow thickness, ulceration and site of the primary tumour. The aims of the present study were to validate this prognostic model externally and to assess whether it could be improved by adding other prognostic factors. METHODS: Patients with sentinel node-negative cutaneous melanoma were included in this retrospective single-institution study. The ß values of the EORTC prognostic model were used to predict recurrence-free survival and melanoma-specific survival. The predictive performance was assessed by discrimination (c-index) and calibration. Seeking to improve the performance of the model, additional variables were added to a Cox proportional hazards model. RESULTS: Some 4235 patients with sentinel node-negative cutaneous melanoma were included. The median follow-up time was 50 (i.q.r. 18·5-81·5) months. Recurrences and deaths from melanoma numbered 793 (18·7 per cent) and 456 (10·8 per cent) respectively. Validation of the EORTC model showed good calibration for both outcomes, and a c-index of 0·69. The c-index was only marginally improved to 0·71 when other significant prognostic factors (sex, age, tumour type, mitotic rate) were added. CONCLUSION: This study validated the EORTC prognostic model for recurrence-free and melanoma-specific survival of patients with negative sentinel nodes. The addition of other prognostic factors only improved the model marginally. The validated EORTC model could be used for personalizing follow-up and selecting high-risk patients for trials of adjuvant systemic therapy.

ANTECEDENTES: Es importante identificar a los pacientes con melanoma y ganglio centinela negativo con alto riesgo de recidiva o muerte. Con este fin, la European Organisation for Research and Treatment of Cancer (EORTC) ha desarrollado recientemente un modelo pronóstico que incluye el índice de Breslow, la presencia de úlcera y la localización del tumor primario. Los objetivos del presente estudio fueron efectuar la validación externa de este modelo pronóstico y evaluar si pudiera mejorarse agregando otros factores pronósticos. MÉTODOS: Estudio retrospectivo de una sola institución, en el que se incluyeron 4.235 pacientes con melanoma cutáneo y ganglio centinela negativo. La mediana de seguimiento fue de 50 meses (rango intercuartílico 18,5-81,5). Para predecir la supervivencia sin recidiva y la supervivencia específica para el melanoma se utilizaron los valores beta del modelo de pronóstico de la EORTC. La capacidad predictiva se evaluó mediante los índices de discriminación (índice c) y de calibración. Para mejorar el rendimiento de este modelo, se agregaron más variables utilizando un modelo de riesgos proporcionales de Cox. RESULTADOS: Las recidivas y muertes por melanoma fueron 793 (19%) y 456 (11%), respectivamente. La validación del modelo EORTC mostró una buena calibración para ambos resultados y un índice c de 0,69. El índice c sólo mejoró marginalmente a 0,71 cuando se agregaron otros factores pronósticos significativos (género, edad, tipo de tumor, índice mitótico). CONCLUSIÓN: La validación externa del modelo de pronóstico EORTC para la supervivencia sin recidiva y específica en pacientes con melanoma y ganglio centinela negativo fue satisfactoria. La adición de otros factores pronósticos solo mejoró marginalmente el modelo. El modelo validado de la EORTC podría utilizarse para personalizar las estrategias de seguimiento y seleccionar a pacientes de alto riesgo para ensayos con terapia sistémica adyuvante.