Interferon-gamma signature as prognostic and predictive marker in macroscopic stage III melanoma.

BACKGROUND: A substantial proportion of patients with macroscopic stage III melanoma do not benefit sufficiently from adjuvant anti-PD-1 therapy, as they either recur despite therapy or would never have recurred. To better inform adjuvant treatment selection, we have performed translational analyses to identify prognostic and predictive biomarkers. PATIENTS AND METHODS: Two cohorts of patients with macroscopic stage III melanoma from an ongoing biobank study were included. Clinical data were compared between an observation cohort (cohort 1) and an adjuvant intention cohort (cohort 2). RNA sequencing for translational analyses was performed and treatment subgroups (cohort 1A and cohort 2A) were compared for possible biomarkers, using a cut-off based on the treatment-naïve patients. In addition, two validation cohorts (Melanoma Institute Australia (MIA) and University Medical Centre Utrecht (UMCU)) were obtained. RESULTS: After a median follow-up of 26 months of the 98 patients in our discovery set, median recurrence-free survival (RFS) was significantly longer for the adjuvant intention cohort (cohort 2, n=49) versus the observation cohort (cohort 1, n=49). Median overall survival was not reached for either cohort, nor significantly different. In observation cohort 1A (n=24), RFS was significantly longer for patients with high interferon-gamma (IFNγ) score (p=0.002); for adjuvant patients of cohort 2A (n=24), a similar trend was observed (p=0.086). Patients with high B cell score had a longer RFS in cohort 1A, but no difference was seen in cohort 2A. The B cell score based on RNA correlated with CD20+ cells in tumor area but was not independent from the IFNγ score. In the MIA validation cohort (n=44), longer RFS was observed for patients with high IFNγ score compared with low IFNγ score (p=0.046), no difference in RFS was observed according to the B cell score. In both the observation (n=11) and the adjuvant (n=11) UMCU validation cohorts, no difference in RFS was seen for IFNγ and B cell. CONCLUSIONS: IFNγ has shown to be a prognostic marker in both patients who were and were not treated with adjuvant therapy. B cell score was prognostic but did not improve accuracy over IFNγ. Our study confirmed RFS benefit of adjuvant anti-PD-1 for patients with macroscopic stage III melanoma.

Management of infliximab refractory immune checkpoint inhibitor gastrointestinal toxicity: a multicenter case series.

BACKGROUND: Immune checkpoint inhibitor (ICI) gastrointestinal toxicity (gastritis, enteritis, colitis) is a major cause of morbidity and treatment-related death. Guidelines agree steroid-refractory cases warrant infliximab, however best management of infliximab-refractory ICI gastrointestinal toxicity (IRIGItox) is unknown. METHODS: We conducted an international multicenter retrospective case series. IRIGItox was defined as failure of symptom resolution ≤grade 1 (Common Terminology Criteria for Adverse Events V.5.0) following ≥2 infliximab doses or failure of symptom resolution ≤grade 2 after one dose. Data were extracted regarding demographics, steroid use, response to treatment, and survival outcomes. Toxicity was graded at symptom onset and time of infliximab failure. Efficacy of infliximab refractory therapy was assessed by symptom resolution, time to resolution and steroid wean duration. Survival outcomes were examined based on immunosuppressive therapy received. RESULTS: 78 patients were identified: median age 60 years; 56% men; majority melanoma (N=70, 90%); 60 (77%) received anti-cytotoxic T-lymphocyte-associated protein 4 alone or in combination with anti-programmed cell death protein-1 and most had colitis (N=74, 95%). 106 post-infliximab treatments were given: 31 calcineurin inhibitors (CNIs); 27 antimetabolites (mycophenolate, azathioprine); 16 non-systemic immunomodulatory agents (eg, mesalazine or budesonide); 15 vedolizumab; 5 other biologics (anti-interleukin-12/23, 16, Janus kinase inhibitors) and 7 interventional procedures (including colectomy); 5 did not receive post-infliximab therapy. Symptom resolution was achieved in most (N=23/31, 74%) patients treated with CNIs; 12/27 (44%) with antimetabolites; 7/16 (44%) with non-systemic immunomodulation, 8/15 (53%) with vedolizumab and 5/7 (71%) with interventional procedures. No non-vedolizumab biologics resulted in toxicity resolution. CNIs had the shortest time to symptom resolution (12 days) and steroid wean (43 days); however, were associated with poorer event-free survival (6.3 months) and overall survival (26.8 months) than other agents. Conversely, vedolizumab had the longest time to toxicity resolution and steroid wean, 66 and 124 days, but most favorable survival data: EFS 24.5 months; median OS not reached. Six death occurred (three due to IRIGItox or management of toxicity; three with persisting IRIGItox and progressive disease). CONCLUSIONS: IRIGItox causes major morbidity and mortality. Management is heterogeneous. CNIs appear most likely to result in toxicity resolution in the shortest time period, however, are associated with poorer oncological outcomes in contrast to vedolizumab.

Checkpoint Inhibitor-Associated Autoimmune Diabetes Mellitus Is Characterized by C-peptide Loss and Pancreatic Atrophy.

OBJECTIVE: To conduct a multicenter case series characterizing the clinical characteristics at presentation and pancreatic volume changes of patients with checkpoint inhibitor-associated autoimmune diabetes (CIADM). RESEARCH DESIGN AND METHODS: Electronic medical records were reviewed with 36 consecutive patients identified with CIADM, as defined by (1) previous immune checkpoint inhibitor (ICI) therapy, (2) new-onset hyperglycemia (blood glucose level ≥ 11.1 mmol/L and/or glycosylated hemoglobin ≥ 6.5%), and (3) insulin deficiency [C-peptide <0.4 nmol/L or diabetic ketoacidosis (DKA)] within 1 month of presentation. Pancreatic volume was available and measured using computed tomography volumetry for 17 patients with CIADM and 3 sets of control patients: 7 with ICI-related pancreatitis, 13 with asymptomatic ICI-related lipase elevation, and 11 ICI-treated controls for comparison. RESULTS: All patients had either anti-programmed cell death protein 1 or anti-programmed cell death ligand 1 therapy. Median time from ICI commencement to CIADM diagnosis was 15 weeks. At presentation, 25 (69%) had DKA, 27 (84%) had low C-peptide, and, by 1 month, 100% had low C-peptide. Traditional type 1 diabetes autoantibodies were positive in 15/35 (43%). Lipase was elevated in 13/27 (48%) at presentation. In 4 patients with longitudinal lipase testing, elevated levels peaked 1 month prior to CIADM diagnosis. Pancreatic volume was lower pre-ICI in CIADM patients compared with controls and demonstrated a mean decline of 41% from pretreatment to 6 months post-CIADM diagnosis. CONCLUSION: Pronounced biochemical and radiologic changes occur during CIADM pathogenesis. Rapid loss of C-peptide is a distinct characteristic that can be used to aid diagnosis as autoantibodies are often negative.

Classification of the tumor immune microenvironment and associations with outcomes in patients with metastatic melanoma treated with immunotherapies.

BACKGROUND: Tumor microenvironment (TME) characteristics are potential biomarkers of response to immune checkpoint inhibitors in metastatic melanoma. This study developed a method to perform unsupervised classification of TME of metastatic melanoma. METHODS: We used multiplex immunohistochemical and quantitative pathology-derived assessment of immune cell compositions of intratumoral and peritumoral regions of metastatic melanoma baseline biopsies to classify TME in relation to response to anti-programmed cell death protein 1 (PD-1) monotherapy or in combination with anti-cytotoxic T-cell lymphocyte-4 (ipilimumab (IPI)+PD-1). RESULTS: Spatial profiling of CD8+T cells, macrophages, and melanoma cells, as well as phenotypic PD-1 receptor ligand (PD-L1) and CD16 proportions, were used to identify and classify patients into one of three mutually exclusive TME classes: immune-scarce, immune-intermediate, and immune-rich tumors. Patients with immune-rich tumors were characterized by a lower proportion of melanoma cells and higher proportions of immune cells, including higher PD-L1 expression. These patients had higher response rates and longer progression-free survival (PFS) than those with immune-intermediate and immune-scarce tumors. At a median follow-up of 18 months (95% CI: 6.7 to 49 months), the 1-year PFS was 76% (95% CI: 64% to 90%) for patients with an immune-rich tumor, 56% (95% CI: 44% to 72%) for those with an immune-intermediate tumor, and 33% (95% CI: 23% to 47%) for patients with an immune-scarce tumor. A higher response rate was observed in patients with an immune-scarce or immune-intermediate tumor when treated with IPI+PD-1 compared with those treated with PD-1 alone. CONCLUSIONS: Our study provides an automatic TME classification method that may predict the clinical efficacy of immunotherapy for patients with metastatic melanoma.

Efficacy and toxicity of adjuvant radiotherapy in recurrent melanoma after adjuvant immunotherapy.

BACKGROUND: In patients with stage III melanoma, despite surgical resection and adjuvant systemic therapy, locoregional recurrences still occur. The randomized, phase III Trans-Tasman Radiation Oncology Group (TROG) 02.01 trial demonstrated that adjuvant radiotherapy (RT) after complete lymphadenectomy (CLND) halves the incidence of melanoma recurrence within local nodal basins without improving overall survival or quality of life. However, the study was conducted prior to the current era of adjuvant systemic therapies and when CLND was the standard approach for microscopic nodal disease. As such, there is currently no data on the role of adjuvant RT in patients with melanoma who recur during or after adjuvant immunotherapy, including those that may or may not have undergone prior CLND. In this study, we aimed to answer this question. METHODS: Patients with resected stage III melanoma who received adjuvant anti-programmed cell death protein-1 (PD-1) (±ipilimumab) immunotherapy with a subsequent locoregional (lymph node and/or in-transit metastases) recurrence were retrospectively identified. Multivariable logistic and Cox regression analyses were conducted. Primary outcome was rate of subsequent locoregional recurrence; secondary outcomes were locoregional recurrence-free survival (lr-RFS2) and overall RFS (RFS2) to second recurrence. RESULTS: In total, 71 patients were identified: 42 (59%) men, 30 (42%) BRAF V600E mutant, 43 (61%) stage IIIC at diagnosis. Median time to first recurrence was 7 months (1-44), 24 (34%) received adjuvant RT and 47 (66%) did not. Thirty-three patients (46%) developed a second recurrence at a median of 5 months (1-22). The rate of locoregional relapse at second recurrence was lower in those who received adjuvant RT (8%, 2/24) compared with those who did not (36%, 17/47, p=0.01). Adjuvant RT at first recurrence was associated with an improved lr-RFS2 (HR 0.16, p=0.015), with a trend towards an improved RFS2 (HR 0.54, p=0.072) and no effect on risk of distant recurrence or overall survival. CONCLUSION: This is the first study to investigate the role of adjuvant RT in patients with melanoma with locoregional disease recurrence during or after adjuvant anti-PD-1-based immunotherapy. Adjuvant RT was associated with improved lr-RFS2, but not risk of distant recurrence, demonstrating a likely benefit in locoregional disease control in the modern era. Further prospective studies are required to validate these results.

Unveiling the tumor immune microenvironment of organ-specific melanoma metastatic sites.

BACKGROUND: The liver is a known site of resistance to immunotherapy and the presence of liver metastases is associated with shorter progression-free and overall survival (OS) in melanoma, while lung metastases have been associated with a more favorable outcome. There are limited data available regarding the immune microenvironment at different anatomical sites of melanoma metastases. This study sought to characterize and compare the tumor immune microenvironment of liver, brain, lung, subcutaneous (subcut) as well as lymph node (LN) melanoma metastases. METHODS: We analyzed OS in 1924 systemic treatment-naïve patients with AJCC (American Joint Committee on Cancer) stage IV melanoma with a solitary site of organ metastasis. In an independent cohort we analyzed and compared immune cell densities, subpopulations and spatial distribution in tissue from liver, lung, brain, LN or subcut sites from 130 patients with stage IV melanoma. RESULTS: Patients with only liver, brain or bone metastases had shorter OS compared to those with lung, LN or subcutaneous and soft tissue metastases. Liver and brain metastases had significantly lower T-cell infiltration than lung (p=0.0116 and p=0.0252, respectively) and LN metastases (p=0.0116 and p=0.0252, respectively). T cells were further away from melanoma cells in liver than lung metastases (p=0.0335). Liver metastases displayed unique T-cell profiles, with a significantly lower proportion of programmed cell death protein-1+ T cells compared to all other anatomical sites (p<0.05), and a higher proportion of TIM-3+ T cells compared to LN (p=0.0004), subcut (p=0.0082) and brain (p=0.0128) metastases. Brain metastases had a lower macrophage density than subcut (p=0.0105), liver (p=0.0095) and lung (p<0.0001) metastases. Lung metastases had the highest proportion of programmed death ligand-1+ macrophages of the total macrophage population, significantly higher than brain (p<0.0001) and liver metastases (p=0.0392). CONCLUSIONS: Liver and brain melanoma metastases have a significantly reduced immune infiltrate than lung, subcut and LN metastases, which may account for poorer prognosis and reduced immunotherapy response rates in patients with liver or brain metastases. Increased TIM-3 expression in liver metastases suggests TIM-3 inhibitor therapy as a potential therapeutic opportunity to improve patient outcomes.