Background: Biomarkers for predicting response to immune checkpoint inhibitors (ICI) are scarce and often lack external validation. This study provides a comprehensive investigation of pretreatment C-reactive protein (CRP) levels as well as its longitudinal trajectories as a marker of treatment response and disease outcome in patients with advanced non-small cell lung cancer (NSCLC) undergoing immunotherapy with anti PD-1 or anti PD-L1 agents. Methods: We performed a retrospective bi-center study to assess the association between baseline CRP levels and anti PD-(L)1 treatment outcomes in the discovery cohort (n = 90), confirm these findings in an external validation cohort (n = 101) and explore the longitudinal evolution of CRP during anti PD-(L)1 treatment and the potential impact of dynamic CRP changes on treatment response and disease outcome in the discovery cohort. Joint models were implemented to evaluate the association of longitudinal CRP trajectories and progression risk. Primary treatment outcomes were progression-free survival (PFS) and overall survival (OS), while the objective response rate (ORR) was a secondary outcome, respectively. Results: In the discovery cohort, elevated pretreatment CRP levels emerged as independent predictors of worse PFS (HR per doubling of baseline CRP = 1.37, 95% CI: 1.16–1.63, p < 0.0001), worse OS (HR per doubling of baseline CRP = 1.42, 95% CI: 1.18–1.71, p < 0.0001) and a lower ORR ((odds ratio (OR) of ORR per doubling of baseline CRP = 0.68, 95% CI: 0.51–0.92, p = 0.013)). In the validation cohort, pretreatment CRP could be fully confirmed as a predictor of PFS and OS, but not ORR. Elevated trajectories of CRP during anti PD-(L)1 treatment (adjusted HR per 10 mg/L increase in CRP = 1.22, 95% CI: 1.15–1.30, p < 0.0001), as well as a faster increases of CRP over time (HR per 10 mg/L/month faster increase in CRP levels = 13.26, 95% CI: 1.14–154.54, p = 0.039) were strong predictors of an elevated progression risk, whereas an early decline of CRP was significantly associated with a reduction in PFS risk (HR = 0.91, 95% CI: 0.83–0.99, p = 0.036), respectively. Conclusion: These findings support the concept that CRP should be further explored by future prospective studies as a simple non-invasive biomarker for assessing treatment benefit during anti PD-(L)1 treatment in advanced NSCLC.

Metastatic testicular germ cell tumors (TGCTs) are a potentially curable disease by administration of risk-adapted cytotoxic chemotherapy. Nevertheless, a disease-relapse after curative chemotherapy needs more intensive salvage chemotherapy and significantly worsens the prognosis of TGCT patients. Circulating tumor markers (β-subunit of human chorionic gonadotropin (β-HCG), alpha-Fetoprotein (AFP), and Lactate Dehydrogenase (LDH)) are frequently used for monitoring disease recurrence in TGCT patients, though they lack diagnostic sensitivity and specificity. Increasing evidence suggests that serum levels of stem cell-associated microRNAs (miR-371a-3p and miR-302/367 cluster) are outperforming the traditional tumor markers in terms of sensitivity to detect newly diagnosed TGCT patients. The aim of this study was to investigate whether these miRNAs are also informative in detection of disease recurrence in TGCT patients after curative first line therapy. For this purpose, we measured the serum levels of miR-371a-3p and miR-367 in 52 samples of ten TGCT patients at different time points during disease relapse and during salvage chemotherapy. In our study, miR-371a-3p levels in serum samples with proven disease recurrence were 13.65 fold higher than levels from the same patients without evidence of disease (p = 0.014). In contrast, miR-367 levels were not different in these patient groups (p = 0.985). In conclusion, miR-371a-3p is a sensitive and potentially novel biomarker for detecting disease relapse in TGCT patients. This promising biomarker should be investigated in further large prospective trials.

Use of signal transduction inhibitors as single agents to treat cancer leads to resistance because of the plasticity of intracellular signaling, and combination therapy can overcome this. We describe the first-in-human trial of avutometinib (RAF–MEK clamp) and defactinib (focal adhesion kinase inhibitor) in patients with solid tumors. The trial met its primary endpoint and recommended a phase 2 dose and schedule. The recommended phase 2 dose and schedule for a 28-day cycle was determined to be avutometinib 3.2 mg once a day, twice weekly (Monday and Thursday or Tuesday and Friday), and defactinib 200 mg twice a day, seven days a week. Both drugs were administered orally on a 3 weeks ‘on’ and 1 week ‘off’ basis. The pharmacokinetics and pharmacodynamics were consistent with previous reports of avutometinib and defactinib used as single agents. Key findings include an objective response rate of 42.3% (11 of 26; 95% confidence interval 23.4–63.1) and a median progression-free survival of 20.1 months (95% confidence interval 11.2–43.9) in patients with low-grade serous ovarian cancer. This study demonstrates the importance of intermittent dosing schedules in combined targeting of the mitogen-activated protein kinase and focal adhesion kinase pathways to improve tolerability, and has acquired proof of concept of anti-tumor activity against low-grade serous ovarian cancer, a tumor relatively resistant to chemotherapy. ClinicalTrials.gov identifier NCT03875820.

Background C reactive protein (CRP) kinetics have recently been suggested as predictive biomarkers for the efficacy of immune checkpoint inhibitor (ICI) therapy in selected cancer types. The aim of this study was to characterize early CRP kinetics as a tumor-agnostic biomarker for ICI treatment outcomes. Methods In this multicenter retrospective cohort study, two independent cohorts of patients with various cancer types undergoing palliative ICI treatment at Austrian academic centers served as the discovery (n=562) and validation cohort (n=474). Four different patterns of CRP kinetics in the first 3 months of ICI therapy were defined (CRP-flare responders, CRP-responders, CRP non-responders, patients with all-normal CRP). Objective response rate (ORR), progression-free survival (PFS) and overall survival (OS) were defined as coprimary endpoints. Univariable and multivariable logistic regression, landmark analysis and Cox regression including CRP kinetics as time-dependent variable were performed. Results The ORR in patients with all-normal CRP, CRP responders, CRP flare-responders and CRP non-responders was 41%, 38%, 31% and 12%, respectively. The median OS and PFS estimates were 24.5 months (95% CI 18.5 to not reached) and 8.2 months (95% CI 5.9 to 12.0) in patients with all-normal CRP, 16.1 months (95% CI 12.6 to 19-8) and 6.1 months (95% CI 4.9 to 7.2) in CRP-responders, 14.0 months (95% CI 8.5 to 19.4) and 5.7 months (95% CI 4.1 to 8.5) in CRP flare-responders and 8.1 months (95% CI 5.8 to 9.9) and 2.3 months (95% CI 2.2 to 2.8) in CRP non-responders (log-rank p for PFS and OS<0.001). These findings prevailed in multivariable analysis and could be fully confirmed in our validation cohort. Pooled subgroup analysis suggested a consistent predictive significance of early CRP kinetics for treatment efficacy and outcome independent of cancer type. Conclusion Early CRP kinetics represent a tumor-agnostic predictor for treatment response, progression risk and mortality in patients with cancer undergoing ICI therapy.

Background The use and approval of immune checkpoint inhibitors for the treatment of non-small cell lung cancer (NSCLC) depends on PD-L1 expression in the tumor tissue. Nevertheless, PD-L1 often fails to predict response to treatment. One possible explanation could be a change in PD-L1 expression during the course of the disease and the neglect of reassessment. The purpose of this study was a longitudinal analysis of PD-L1 expression in patients with relapsed NSCLC. Methods We retrospectively analyzed PD-L1 expression in patients with early-stage NSCLC and subsequent relapse in preoperative samples, matched surgical specimens and biopsy samples of disease recurrence. Ventana PD-L1 (SP263) immunohistochemistry assay was used for all samples. PD-L1 expression was scored based on clinically relevant groups (0%, 1%–49%, and ≥50%). The primary endpoint was the change in PD-L1 score group between preoperative samples, matched surgical specimens and relapsed tumor tissue. Results 395 consecutive patients with stages I–III NSCLC and 136 (34%) patients with a subsequent relapse were identified. For 87 patients at least two specimens for comparison of PD-L1 expression between early stage and relapsed disease were available. In 72 cases, a longitudinal analysis between preoperative biopsy, the surgically resected specimen and biopsy of disease recurrence was feasible. When comparing preoperative and matched surgical specimens, a treatment-relevant conversion of PD-L1 expression group was found in 25 patients (34.7%). Neoadjuvant treatment showed no significant effect on PD-L1 alteration (p=0.39). In 32 (36.8%) out of 87 cases, a change in PD-L1 group was observed when biopsies of disease relapse were compared with early-stage disease. Adjuvant treatment was not significantly associated with a change in PD-L1 expression (p=0.53). 39 patients (54.2%) showed at least 1 change into a different PD-L1 score group during the course of disease. 14 patients (19.4%) changed the PD-L1 score group twice, 5 (6.9%) of them being found in all different score groups. Conclusion PD-L1 expression shows dynamic changes during the course of disease. There is an urgent need for consensus guidelines to define a PD-L1 testing strategy including time points of reassessment, the number of biopsies to be obtained and judgment of surgical specimens.

Radiation therapy is a possible treatment strategy for patients with testicular seminoma after orchiectomy in clinical stage I or II disease. Little is known about the outcome of patients who experience a relapse after radiation therapy. Data from 61 patients who relapsed after adjuvant or curative radiation therapy from 17 centers in 11 countries were collected and retrospectively analyzed. Primary outcomes were disease-free and overall survival. Secondary outcomes were time to relapse, stage at relapse, treatment for relapse, and rate of febrile neutropenia during chemotherapy for relapse. With a median follow-up of 9.9 years (95% confidence interval [CI], 7.5-10.9), we found a 5-year disease-free survival of 90% (95% CI, 79-95) and a 5-year overall survival of 98% (95% CI, 89-100). Sixty-six percent of patients had stage III disease at time of relapse and 93% of patients fell into the good prognosis group per the International Germ Cell Cancer Collaborative Group classification. The median time to relapse after radiation therapy was 15.6 months (95% CI, 12-23). Twenty-two (36%) patients relapsed more than 2 years after radiation therapy and 7 (11.5%) patients relapsed more than 5 years after radiation therapy. One-third of relapses was detected owing to patients' symptoms, whereas two-thirds of relapses were detected during routine follow-up. The majority (93%) of cases were treated with cisplatin-based chemotherapy. The rate of febrile neutropenia during chemotherapy was 35%. Five patients experienced a second relapse. At last follow-up, 55 patients (90%) were alive without disease. Only 1 patient died owing to disease progression. Cisplatin-based chemotherapy for patients with seminoma who have relapsed after treatment with radiation therapy alone leads to excellent outcomes. Patients and physicians should be aware of possible late relapses after radiation therapy.