A randomized phase II clinical trial of stereotactic body radiation therapy (SBRT) and systemic pembrolizumab with or without intratumoral avelumab/ipilimumab plus CD1c (BDCA-1)+/CD141 (BDCA-3)+ myeloid dendritic cells in solid tumors.

BACKGROUND: Radiotherapy (RT) synergizes with immune checkpoint blockade (ICB). CD1c(BDCA-1)+/CD141(BDCA-3)+ myeloid dendritic cells (myDC) in the tumor microenvironment are indispensable at initiating effector T-cell responses and response to ICB. METHODS: In this phase II clinical trial, anti-PD-1 ICB pretreated oligometastatic patients (tumor agnostic) underwent a leukapheresis followed by isolation of CD1c(BDCA-1)+/CD141(BDCA-3)+ myDC. Following hypofractionated stereotactic body RT (3 × 8 Gy), patients were randomized (3:1). Respectively, in arm A (immediate treatment), intratumoral (IT) ipilimumab (10 mg) and avelumab (40 mg) combined with intravenous (IV) pembrolizumab (200 mg) were administered followed by IT injection of myDC; subsequently, IV pembrolizumab and IT ipilimumab/avelumab were continued (q3W). In arm B (contemporary control arm), patients received IV pembrolizumab, with possibility to cross-over at progression. Primary endpoint was 1-year progression-free survival rate (PFS). Secondary endpoints were safety, feasibility, objective response rate, PFS, and overall survival (OS). RESULTS: Thirteen patients (10 in arm A, eight non-small cell lung cancer, and five melanoma) were enrolled. Two patients crossed over. One-year PFS rate was 10% in arm A and 0% in arm B. Two patients in arm A obtained a partial response, and one patient obtained a stable disease as best response. In arm B, one patient obtained a SD. Median PFS and OS were 21.8 weeks (arm A) versus 24.9 (arm B), and 62.7 versus 57.9 weeks, respectively. An iatrogenic pneumothorax was the only grade 3 treatment-related adverse event. CONCLUSION: SBRT and pembrolizumab with or without IT avelumab/ipilimumab and IT myDC in oligometastatic patients are safe and feasible with a clinically meaningful tumor response rate. However, the study failed to reach its primary endpoint. TRIAL REGISTRATION NUMBER: Clinicaltrials.gov: NCT04571632 (09 AUG 2020). EUDRACT: 2019-003668-32. Date of registration: 17 DEC 2019, amendment 1: 6 MAR 2021, amendment 2: 4 FEB 2022.

Regorafenib in patients with pretreated advanced melanoma: a single-center case series.

Melanoma patients failing all approved treatment options have a poor prognosis. The antimelanoma activity of regorafenib (REGO), a multitargeted kinase inhibitor, has not been investigated in this patient population. The objective response rate and safety of REGO treatment in advanced melanoma patients was investigated retrospectively. Twenty-seven patients received REGO treatment. All patients had progressed on anti-programmed cell death protein 1 (PD-1) and anti-cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) checkpoint inhibition and BRAF/MEK inhibitors (in case of a BRAF V600 mutation). REGO was administered in continuous dosing and combined (upfront or sequentially) with nivolumab ( n  = 5), trametinib ( n  = 8), binimetinib ( n  = 2), encorafenib ( n  = 1), dabrafenib/trametinib ( n  = 9), or encorafenib/binimetinib ( n  = 7). The best overall response was partial response (PR) in five patients (18.5%) and stable disease in three patients (11.1%). Three of seven (42.8%) BRAF V600mut patients treated with REGO in combination with BRAF/MEK inhibitors obtained a PR (including regression of brain metastases in all three patients). In addition, PR was documented in a BRAF V600mut patient treated with REGO plus anti-PD-1, and a NRASQ61mut patient treated with REGO plus a MEK inhibitor. Common grade 3-4 treatment-related adverse events included arterial hypertension ( n  = 7), elevated transaminase levels ( n  = 5), abdominal pain ( n  = 3), colitis ( n  = 2), anorexia ( n  = 1), diarrhea ( n  = 1), fever ( n  = 1), duodenal perforation ( n  = 1), and colonic bleeding ( n  = 1). Median progression-free survival was 11.0 weeks (95% confidence interval, 7.1-14.9); median overall survival was 23.1 weeks (95% confidence interval, 13.0-33.3). REGO has a manageable safety profile in advanced melanoma patients, in monotherapy as well as combined with BRAF/MEK inhibitors or PD-1 blocking monoclonal antibodies. The triplet combination of REGO with BRAF/MEK inhibitors appears most active, particularly in the BRAF V600mut patients.

Successful treatment of MAP2K1 mutant stage IV-M1d melanoma with trametinib plus low-dose dabrafenib: a case report.

Clonal MAPK-pathway activating mutations in the MAP2K1 (MEK1) gene are present in approximately 9% of cutaneous melanomas. These mutations are divided into three classes: RAF-dependent, RAF-regulated, RAF-independent. Cell lines with class-2 or RAF-regulated MAP2K1-mutations are most responsive to MEK-inhibitors. We present a patient with a class-2 MAP2K1-mutant stage IV-M1d melanoma who experienced extra- and intracranial progressive disease following treatment with immune-checkpoint inhibitors. The patient was treated with the MEK-inhibitor trametinib (2 mg OD) to which a low-dose of dabrafenib (50 mg BID) was added to mitigate skin-toxicity. Following documentation of a partial response (PR), she developed one new, and increase in volume of two pre-existing brain metastases that were treated with stereotactic radiosurgery (SRS) while continuing trametinib and dabrafenib. Thereafter, a deep partial radiologic and metabolic response both extra-and intra-cranially was achieved and is ongoing 88 weeks after initiating trametinib. She experienced no grade > 2 adverse events. Focal post-radiation necrosis at site of an irradiated brain metastasis developed 9 months after SRS and is successfully being treated with low-dose bevacizumab. This is the first published case of a durable intracranial disease control with the MEK-inhibitor trametinib of a stage IV-M1d class-2 MAP2K1-mutant melanoma. This illustrates the utility of NGS profiles that include class-1/2 MAP2K1-mutations in patients with melanoma and other malignancies to provide valuable information on a potentially active individualized treatment option. A prospective clinical trial that further evaluates the efficacy of MEK-inhibitor therapies in MAP2K1-mutated tumors is justified.

Detection of cell-free tumor DNA in cerebrospinal fluid as a diagnostic biomarker for leptomeningeal melanoma metastasis: A case series.

Leptomeningeal melanoma metastases (LMM) are associated with poor survival. Diagnosis is based on clinical presentation, brain MRI and cerebrospinal fluid (CSF) analysis. Inconclusive findings at initial presentation can delay treatment. In this single-center case series, detection of BRAFV600- and NRASQ61-mutant cell-free tumor DNA (cfDNA) in CSF was evaluated as a complementary diagnostic biomarker. In 12 patients with clinical suspicion of LMM, a retrospective analysis of MRI, CSF cytology and cfDNA analysis on 1 mL of CSF using the Idylla® platform was carried out. Nine patients displayed MRI abnormalities suggesting LMM. CSF analysis identified malignant cells in three patients (including one without MRI abnormalities). BRAFV600- or NRASQ61-mutant cfDNA was detected in CSF of nine patients (eight with and one without MRI abnormalities; all patients with positive CSF cytology). Subsequent follow-up confirmed LMM in all patients with positive and in one patient with a negative CSF cfDNA analysis (sensitivity 81.8%; specificity 100%). Our findings suggest that analyzing BRAFV600- and NRASQ61-mutant cfDNA in CSF using the Idylla® platform holds promise as a sensitive and specific complementary diagnostic biomarker for LMM, particularly in case of inconsistency between imaging and CSF cytology. The 110-min analysis can facilitate urgent treatment decisions.

Unraveling the spectrum of inflammatory myofibroblastic tumors in the lung: A comprehensive case series highlighting endobronchial, pleural, and lung parenchymal tumors.

Objectives: Diverse cases of inflammatory myofibroblastic tumors (IMTs) in the lung (pleural, endobronchial, and parenchymal) are presented while discussing the (preoperative) diagnostic challenges and treatment modalities. Other objectives include emphasizing the significance of gene rearrangements and highlighting the multidisciplinary approach in addressing IMTs. Methods: Four cases of IMT in the lung are presented, including a young adolescent girl with an ETV6-neurotrophic tyrosine receptor kinase 3 (NTRK3) gene rearrangement, a 5-year-old boy with challenging preoperative diagnosis, and 2 middle-aged women with respectively pleural and endobronchial tumors with one peribronchial relapse. Results: The cases demonstrate the diverse clinical presentations and diagnostic complexities associated with IMT in the lung. Surgical resection remains the primary treatment modality, with complete resection leading to a cure in most patients. Unfortunately, aggressive relapse can occur, as in our last case of an endobronchial tumor. Frozen section may confirm the presence of malignant cells perioperatively and impact further treatment. The presence of gene rearrangements, such as ETV6-NTRK3, suggests potential therapeutic implications. Conclusions: Early detection and complete surgical removal of IMT are crucial for effective treatment. Identifying gene rearrangements such as ETV6-NTRK3 holds promise for targeted therapies. Diagnostic challenges, including the controversy of biopsies and preoperative evaluations, underscore the importance of a multidisciplinary approach. Anatomopathological recognition of IMT stays demanding. Close surveillance is necessary due to potential relapse, whereas frozen section perioperatively can help further treatment. This case series emphasizes the diagnostic challenges and therapeutic considerations for IMT in the lung.

Intratumoral administration of the immunologic adjuvant AS01B in combination with autologous CD1c (BDCA-1)+/CD141 (BDCA-3)+ myeloid dendritic cells plus ipilimumab and intravenous nivolumab in patients with refractory advanced melanoma.

BACKGROUND: Patients with advanced melanoma who progress after treatment with immune checkpoint-inhibitors (ICI) and BRAF-/MEK-inhibitors (if BRAF V600 mutated) have no remaining effective treatment options. The presence of CD1c (BDCA-1)+ and CD141 (BDCA-3)+ myeloid dendritic cells (myDC) in the tumor microenvironment correlates with pre-existing immune recognition and responsiveness to immune checkpoint blockade. The synthetic saponin-based immune adjuvant AS01B enhances adaptive immunity through the involvement of myDC. METHODS: In this first-in-human phase I clinical trial, patients with metastatic melanoma refractory to ICI and BRAF-/MEK inhibitors (when indicated) were recruited. Patients received an intravenous administration of low-dose nivolumab (10 mg, every 2 weeks) plus an intratumoral (IT) administration of 10 mg ipilimumab and 50 µg (0.5 mL) AS01B (every 2 weeks). All myDC, isolated from blood, were injected on day 2 into the same metastatic lesion. Tumor biopsies and blood samples were collected at baseline and repeatedly on treatment. Multiplex immunohistochemistry (mIHC) was performed on biopsy sections to characterize and quantify the IT and peritumoral immune cell composition. RESULTS: Study treatment was feasible and well tolerated without the occurrence of unexpected adverse events in all eight patients. Four patients (50%) obtained a complete response (CR) in the injected lesions. Of these, two patients obtained an overall CR, and one patient a partial response. All responses are ongoing after more than 1 year of follow-up. One additional patient had a stable disease as best response. The disease control rate was 50%. Median progression-free survival and overall survival were 24.1 and 41.9 weeks, respectively. Baseline tumor biopsies from patients who responded to treatment had features of T-cell exclusion. During treatment, there was an increased T-cell infiltration, with a reduced mean distance between T cells and tumor cells. Peripheral blood immune cell composition did not significantly change during study treatment. CONCLUSIONS: Combining an intratumoral injection of CD1c (BDCA-1)+ and CD141 (BDCA-3)+ myDC with repeated IT administration of ipilimumab and AS01B and systemic low-dose nivolumab is safe, feasible with promising early results, worthy of further clinical investigation. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov identifier NCT03707808.

Low-Dose Bevacizumab for the Treatment of Focal Radiation Necrosis of the Brain (fRNB): A Single-Center Case Series.

Focal radiation necrosis of the brain (fRNB) is a late adverse event that can occur following the treatment of benign or malignant brain lesions with stereotactic radiation therapy (SRT) or stereotactic radiosurgery (SRS). Recent studies have shown that the incidence of fRNB is higher in cancer patients who received immune checkpoint inhibitors. The use of bevacizumab (BEV), a monoclonal antibody that targets the vascular endothelial growth factor (VEGF), is an effective treatment for fRNB when given at a dose of 5-7.5 mg/kg every two weeks. In this single-center retrospective case series, we investigated the effectiveness of a low-dose regimen of BEV (400 mg loading dose followed by 100 mg every 4 weeks) in patients diagnosed with fRNB. A total of 13 patients were included in the study; twelve of them experienced improvement in their existing clinical symptoms, and all patients had a decrease in the volume of edema on MRI scans. No clinically significant treatment-related adverse effects were observed. Our preliminary findings suggest that this fixed low-dose regimen of BEV can be a well-tolerated and cost-effective alternative treatment option for patients diagnosed with fRNB, and it is deserving of further investigation.