Guidelines for the evaluation of immune therapy activity in solid tumors: immune-related response criteria

[Emergencies in cancer immunotherapy]

BACKGROUND

Immunomodulatory therapies are becoming increasingly important in uro-oncology. For this reason, we will probably be increasingly confronted with side effects. In addition, there is an increasing number of combinations with other mechanisms of action. Immune-mediated side effects may occur as a consequence of this therapy. These are different from the side effects of chemotherapy and other targeted therapies and therefore require different treatment strategies.

AIM

Based on the current literature, the data on graduation and stage-dependent management will be presented as well as illustrated with examples from practice.

MATERIALS AND METHODS

Literature review on the detection and therapeutic management of adverse events mediated in the setting of immuno-oncologic therapy.

RESULTS

Treatment-related events can in principle affect all organ systems. Toxicities in the area of the skin, such as rash or pruritus, hypo- or hyperthyreosis, arthritis, muscle pain and gastrointestinal symptoms are frequently seen. In terms of frequency, most side effects are grade 1 to 2, but grade 3 to 4 toxicities are also generally well treatable if detected early. Rare complications such as neurological toxicities, pneumonitis or carditis can develop a fulminant course if diagnosed too late.

CONCLUSIONS

Even emergencies are manageable if we know the most important side effects and the therapeutic options. Immune-mediated side effects are of particular importance because they can affect any organ system. However, as long as we consider the possibility of toxicity from checkpoint inhibitors when the patient presents with symptoms, most side effects are easy to treat and therefore manageable.

Evaluation of potential biomarkers for lenvatinib plus pembrolizumab among patients with advanced endometrial cancer: results from Study 111/KEYNOTE-146

BACKGROUND

Lenvatinib plus pembrolizumab demonstrated clinically meaningful benefit in patients with previously treated advanced endometrial carcinoma in Study 111/KEYNOTE-146 (NCT02501096). In these exploratory analyses from this study, we evaluated the associations between clinical outcomes and gene expression signature scores and descriptively summarized response in biomarker subpopulations defined by tumor mutational burden (TMB) and DNA variants for individual genes of interest.

METHODS

Patients with histologically confirmed metastatic endometrial carcinoma received oral lenvatinib 20 mg once daily plus intravenous pembrolizumab 200 mg every 3 weeks for 35 cycles. Archived formalin-fixed paraffin-embedded tissue was obtained from all patients. T-cell-inflamed gene expression profile (TcellinfGEP) and 11 other gene signatures were evaluated by RNA sequencing. TMB, hotspot mutations in PIK3CA (oncogene), and deleterious mutations in PTEN and TP53 (tumor suppressor genes) were evaluated by whole-exome sequencing (WES).

RESULTS

93 and 79 patients were included in the RNA-sequencing-evaluable and WES-evaluable populations, respectively. No statistically significant associations were observed between any of the RNA-sequencing signature scores and objective response rate or progression-free survival. Area under the receiver operating characteristic curve values for response ranged from 0.39 to 0.54; all 95% CIs included 0.50. Responses were seen regardless of TMB (≥175 or <175 mutations/exome) and mutation status. There were no correlations between TcellinfGEP and TMB, TcellinfGEP and microvessel density (MVD), or MVD and TMB.

CONCLUSIONS

This analysis demonstrated efficacy for lenvatinib plus pembrolizumab regardless of biomarker status. Results from this study do not support clinical utility of the evaluated biomarkers. Further investigation of biomarkers for this regimen is warranted.

TRIAL REGISTRATION NUMBER

NCT02501096.

Navigating the ICI Combination Treatment Journey: Patterns of Response and Progression to First-Line ICI-Based Combination Treatment in Metastatic Renal Cell Carcinoma

The use of immune checkpoint inhibitors (ICIs) in combination with tyrosine kinase inhibitors or other ICIs has significantly improved the prognosis for patients with mccRCC. This marks a major milestone in the treatment of mccRCC. Nonetheless, most patients will discontinue first-line therapy. In this narrative review, we analyze the different patterns of treatment discontinuation in the four pivotal phase III trials that have shown an improvement in overall survival in mccRCC first-line therapy, starting from 1 January 2017 to 1 June 2023. We highlight the different discontinuation scenarios and their influences on subsequent treatment options, aiming to provide more data to clinicians to navigate a complex decision-making process through a narrative review approach. We have identified several causes for discontinuations for patients treated with ICI-based combinations, such as interruption for drug-related adverse events, ICI treatment completion, treatment discontinuation due to complete response or maximum clinical benefit, or due to progression (pseudoprogression, systemic progression, and oligoprogression); for each case, an extensive analysis of the trials and current medical review has been conducted.

Immune checkpoint inhibitors: Assessment of the performance and the agreement of iRECIST, irRC, and irRECIST

INTRODUCTION

Immunotherapy has become more widely accepted and used by medical oncologists. Radiologists face challenges in assessing tumor response and becoming more involved in the management of treatment. We aimed to assess the agreement between immune-related response criteria (irRC), immune-related RECIST (irRECIST), and immune RECIST (iRECIST) to correlate the response measured by them with overall survival (OS), and to determine the confirmation rate of progressive disease (PD).

METHODS

A total of 43 patients (28 men, 15 women; average age = 54.6 ± 15.7 years) treated with immunotherapy were included in this study. Pairwise agreements between iRECIST, irRC, and irRECIST were calculated using Cohen's kappa statistics. The correlation of the criteria-based response and OS was evaluated using the Kaplan-Meier method and log-rank test. A confirmation rate with 95% confidence intervals (CI) was calculated in patients with PD.

RESULTS

The kappa values between iRECIST and irRC, iRECIST and irRECIST, and irRC and irRECIST were 0.961 (almost perfect; P < 0.001), 0.961 (almost perfect; P < 0.001), and 0.922 (almost perfect; P < 0.001), respectively. The Kaplan-Meier method and log-rank test showed for each criterion a statistically significant correlation with OS (P < 0.05). The confirmation rates of PD for irRC, irRECIST, and iRECIST were 95% (19/20; 95% CI = 76.4-99.1%), 90% (18/20; 95% CI = 69.9-97.2%), and 90.5% (19/21; 95% CI = 71.1-97.4%), respectively.

CONCLUSION

There was an almost perfect and statistically significant agreement between iRECIST, irRC, and irRECIST. The measurements performed with them significantly correlated with the OS; their confirmation rates were similar. iRECIST and irRECIST might be favored over irRC because of their relative ease of use.

CYFRA 21-1, CA 125 and CEA provide additional prognostic value in NSCLC patients with stable disease at first CT scan

BACKGROUND

Serum tumor markers (STM) may complement imaging and provide additional clinical information for patients with non-small cell lung cancer (NSCLC).

OBJECTIVE

To determine whether STMs can predict outcomes in patients with stable disease (SD) after initial treatment.

METHODS

This single-center, prospective, observational trial enrolled 395 patients with stage III/IV treatment-naïve NSCLC; of which 263 patients were included in this analysis. Computed Tomography (CT) scans were performed and STMs measured before and after initial treatment (two cycles of chemotherapy and/or an immune checkpoint inhibitor or tyrosine kinase inhibitor); analyses were based on CT and STM measurements obtained at first CT performed after cycle 2 only PFS and OS were analyzed by Kaplan-Meier curves and Cox-proportional hazard models.

RESULTS

When patients with SD (n = 100) were split into high- and low-risk groups based on CYFRA 21-1, CEA and CA 125 measurements using an optimized cut-off, a 4-fold increase risk of progression or death was estimated for high- vs low-risk SD patients (PFS, HR 4.17; OS, 3.99; both p < 0.0001). Outcomes were similar between patients with high-risk SD or progressive disease (n = 35) (OS, HR 1.17) and between patients with low-risk SD or partial response (n = 128) (PFS, HR 0.98; OS, 1.14).

CONCLUSIONS

STMs can provide further guidance in patients with indeterminate CT responses by separating them into high- and low-risk groups for future PFS and OS events.

Progress in the research of immunotherapy‑related hyperprogression (Review)

Immunotherapy has become an effective method for the treatment of a variety of malignant tumors. However, with the development of immunotherapy, the phenomenon of hyperprogression in patients with cancer has gradually attracted attention. Hyperprogression refers to a condition in which the progression of a disease during treatment of a patient with cancer is suddenly accelerated. To date, no reliable marker has been found to predict accelerated tumor growth during immune checkpoint inhibitor (ICI) treatment. The aim the present study was to summarize the definition of hyperprogression and the difference between hyperprogression and pseudocytosis, and investigate the potential mechanisms of hyperprogression including clinical characteristics, potential molecular markers and the immune microenvironment. The effect of macrophage-related different types and factors on tumors in the immune microenvironment was analyzed, and the findings may be used to determine the future directions of research in hyperprogression.

[Imaging in immunotherapy for tumor diseases]

Immunotherapeutic agents and in particular immune checkpoint inhibitors (ICI) have opened up extensive new therapeutic possibilities in oncology over the last decade. For numerous entities these substances have improved the clinical outcome, sometimes as monotherapy but also in combination with cytostatic or targeted treatment. In routine clinical practice the type of radiological response often differs from what is seen under cytostatic treatment: a mixed response of individual lesions is more frequently observed and occasionally also a response after an initial progress (so-called pseudoprogression). Furthermore, there is a diverse spectrum of toxicity in the form of immune-related adverse events (irAE), which is observed in large temporal variability to the application. Therefore, early detection and rapid side effect management are essential.

Cancer immunotherapy efficacy and machine learning

INTRODUCTION

Immunotherapy is one of the major breakthroughs in the treatment of cancer, and it has become a powerful clinical strategy, however, not all patients respond to immune checkpoint blockade and other immunotherapy strategies. Applying machine learning (ML) techniques to predict the efficacy of cancer immunotherapy is useful for clinical decision-making.

AREAS COVERED

Applying ML including deep learning (DL) in radiomics, pathomics, tumor microenvironment (TME) and immune-related genes analysis to predict immunotherapy efficacy. The studies in this review were searched from PubMed and ClinicalTrials.gov (January 2023).

EXPERT OPINION

An increasing number of studies indicate that ML has been applied to various aspects of oncology research, with the potential to provide more effective individualized immunotherapy strategies and enhance treatment decisions. With advances in ML technology, more efficient methods of predicting the efficacy of immunotherapy may become available in the future.

PET/CT in the Evaluation of CAR-T Cell Immunotherapy in Hematological Malignancies

Chimeric antigen receptor (CAR)-T cell-based immunotherapy has emerged as a path-breaking strategy for certain hematological malignancies. Assessment of the response to CAR-T therapy using quantitative imaging techniques such as positron emission tomography/computed tomography (PET/CT) has been broadly investigated. However, the definitive role of PET/CT in CAR-T therapy remains to be established. [18F]FDG PET/CT has demonstrated high sensitivity and specificity for differentiating patients with a partial and complete response after CAR-T therapy in lymphoma. The early therapeutic response and immune-related adverse effects such as cytokine release syndrome and immune effector cell-associated neurotoxicity syndrome can also be detected on [18F]FDG PET images. In otherwise asymptomatic lymphoma patients with partial response following CAR-T therapy, the only positive findings could be abnormal PET/CT results. In multiple myeloma, a negative [18F]FDG PET/CT after receiving B-cell maturation antigen-directed CAR-T therapy has been associated with a favorable prognosis. In leukemia, [18F]FDG PET/CT can detect extramedullary metastases and treatment responses after therapy. Hence, PET/CT is a valuable imaging tool for patients undergoing CAR-T therapy for pretreatment evaluation, monitoring treatment response, assessing safety, and guiding therapeutic strategies. Developing guidelines with standardized cutoff values for various PET parameters and tumor cell-specific tracers may improve the efficacy and safety of CAR-T therapy.

Immunologic Signatures of Peripheral Blood T Cells Reveal the Outcome of p53MVA Vaccine and Pembrolizumab Treatment in Patients with Advanced Ovarian Cancer

PURPOSE

Our previous studies indicated that p53-reactive T cells were associated with clinical benefit in patients with advanced ovarian cancer who were treated with p53-expressing modified vaccinia Ankara (p53MVA) vaccine and gemcitabine chemotherapy. To replace chemotherapy with an approach that will enhance vaccine efficacy and antitumor immunity, we treated patients with p53MVA in combination with PD-1 checkpoint blocker, pembrolizumab. We also attempted to further characterize the activation status of T cells prior to vaccination and during treatment.

EXPERIMENTAL DESIGN

Patients received up to three triweekly vaccinations concurrent with pembrolizumab, followed by pembrolizumab monotherapy at 3-week intervals. Correlative studies analyzed peripheral blood T-cell phenotypes and profiles of immune function gene expression.

RESULTS

We observed 6/28 (21%) patients with a clinical benefit to therapy, including 3 partial responses (PR) and 3 patients with stable disease (SD) for 6+ months. The median progression-free survival was 1.8 months (95% confidence interval: 1.7-3.8) and median overall survival was 15.1 months (9.4-30.4). Two patients remain progression-free at 28 and 33 months. Of the 18 patients evaluable in correlative studies, 6 were immunologic responders of whom 5 had clinical benefit (3 PR, 2 SD). Immunologic non-responders expressed in pretreatment peripheral blood mononuclear cell samples high levels of mRNA for multiple molecules associated with terminally differentiated T cells.

CONCLUSIONS

p53MVA/pembrolizumab immunotherapy showed promising antitumor activity in patients who demonstrated functionally competent peripheral blood T cells. Detection of markers of terminally differentiated T cells before treatment may identify patients unlikely to respond to p53MVA/pembrolizumab.

SIGNIFICANCE

The activity of a combination immunotherapy of p53 vaccine and PD-1 checkpoint blockade in patients with platinum-resistant ovarian cancer was evaluated in a phase II trial. Clinical benefit was correlated with the responsive immune status of patients before and during the treatment, defining potential predictive markers for immune therapy.

Mutual communication between radiosensitive and radioresistant esophageal cancer cells modulates their radiosensitivity

Radiotherapy is an important treatment modality for patients with esophageal cancer; however, the response to radiation varies among different tumor subpopulations due to tumor heterogeneity. Cancer cells that survive radiotherapy (i.e., radioresistant) may proliferate, ultimately resulting in cancer relapse. However, the interaction between radiosensitive and radioresistant cancer cells remains to be elucidated. In this study, we found that the mutual communication between radiosensitive and radioresistant esophageal cancer cells modulated their radiosensitivity. Radiosensitive cells secreted more exosomal let-7a and less interleukin-6 (IL-6) than radioresistant cells. Exosomal let-7a secreted by radiosensitive cells increased the radiosensitivity of radioresistant cells, whereas IL-6 secreted by radioresistant cells decreased the radiosensitivity of radiosensitive cells. Although the serum levels of let-7a and IL-6 before radiotherapy did not vary significantly between patients with radioresistant and radiosensitive diseases, radiotherapy induced a more pronounced decrease in serum let-7a levels and a greater increase in serum IL-6 levels in patients with radioresistant cancer compared to those with radiosensitive cancer. The percentage decrease in serum let-7a and the percentage increase in serum IL-6 levels at the early stage of radiotherapy were inversely associated with tumor regression after radiotherapy. Our findings suggest that early changes in serum let-7a and IL-6 levels may be used as a biomarker to predict the response to radiotherapy in patients with esophageal cancer and provide new insights into subsequent treatments.

Case Report: Long-term metabolic response of metastatic uveal melanoma to pembrolizumab on FDG-PET/CT despite a serial pseudoprogressions phenomenon

Uveal melanoma (UV) is a rare and aggressive melanoma with poor 1-year survival. up to 50% of UV patients develop metastases, mainly to the liver. Here, the authors present a 2-deoxy-2-[18F] fluoro-D-glucose positron emission tomography (18F-FDG-PET) study of a very rare case of secondarily metastatic UV in an 81-year-old Caucasian with a dramatic response to pembrolizumab associated with serial pseudogression. 18F-FDG-PET associated with clinical status and peripheral blood derived neutrophil-to-lymphocyte ratio (dNLR) were performed to guide therapeutic strategy due to an atypical pseudoprogression phenomenon.

Progression-free survival, disease-free survival and other composite end points in oncology: improved reporting is needed

Composite outcome measures such as progression-free survival and disease-free survival are increasingly used as surrogate end points in oncology research, frequently serving as the primary end point of pivotal trials that form the basis for FDA and EMA approvals. Such outcome measures combine two or more distinct events (for example, tumour (re)growth, new lesions and/or death) into a single, time-to-event end point. The use of a composite end point can increase the statistical power of a clinical trial and decrease the follow-up period required to demonstrate efficacy, thus lowering costs; however, these end points have a number of limitations. Composite outcomes are often vaguely defined, with definitions that vary greatly between studies, complicating comparisons of results across trials. Altering the makeup of events included in a composite outcome can alter study conclusions, including whether treatment effects are statistically significant. Moreover, the events included in a composite outcome often vary in clinical significance, reflect distinct biological pathways and/or are affected differently by treatment. Therefore, knowing the precise breakdown of the component events is essential to accurately interpret trial results and gauge the true benefit of an intervention. In oncology clinical trials, however, such information is rarely provided. In this Perspective, we emphasize this deficiency through a review of 50 studies with progression-free survival as an outcome published in five top oncology journals, discuss the advantages and challenges of using composite end points, and highlight the need for transparent reporting of the component events.

Supervised clustering of peripheral immune cells associated with clinical response to checkpoint inhibitor therapy in patients with advanced melanoma

Background and purpose

Immune therapy with checkpoint inhibitors (CPIs) is a highly successful therapy in many cancers including metastatic melanoma. Still, many patients do not respond well to therapy and there are no blood-borne biomarkers available to assess the clinical outcome.

Materials and methods

To investigate cellular changes after CPI therapy, we carried out flow cytometry-based immune monitoring in a cohort of 90 metastatic melanoma patients before and after CPI therapy using the FlowSOM algorithm. To evaluate associations to the clinical outcome with therapy, we divided the patients based on progression-free survival.

Results

We found significant associations with CPI therapy in both peripheral blood mononuclear cell and T-cell subsets, but with the most pronounced effects in the latter. Particularly CD4+ effector memory T-cell subsets were associated with response with a positive correlation between CD27+HLA-DR+CD4+ effector memory T cells in a univariate (odds ratio: 1.07 [95% confidence interval 1.02-1.12]) and multivariate regression model (odds ratio: 1.08 [95% confidence interval 1.03-1.14]). We also found a trend towards stronger accumulation of CD57+CD8+ T cells in non-responding patients.

Conclusion

Our results show significant associations between immune monitoring and clinical outcome of therapy that could be evaluated as biomarkers in a clinical setting.

Role of enhancement modifications in evaluating tumor response to immunotherapy in metastatic renal cell carcinoma

INTRODUCTION

Evaluation of tumor response according only to dimensional criteria may underestimate treatment benefit in patients treated for metastatic renal cell carcinoma (RCC). In this study we evaluated the role of lesion enhancement modifications and Choi criteria in patients affected by renal cell carcinoma treated with immunotherapy.

METHODS

We collected data of 60 consecutive patients (with a total of 154 measurable lesions) treated with immunotherapy (nivolumab or ipilimumab plus nivolumab) at a single Institution. We evaluated tumour response using both RECIST1.1 criteria and Choi criteria at the first radiological assessment; we subsequently associated response with progression free survival and overall survival.

RESULTS

Choi criteria found a higher rate of objective response compared to RECIST criteria (38.3% vs 18.3%). An objective response according to both criteria was associated with longer progression free survival and overall survival. Response rate for Choi did not vary according to lesion site.

CONCLUSION

Choi criteria seemed to be able to predict clinical benefit in a higher proportion of patients with renal cell carcinoma treated with immunotherapy than RECIST criteria. Partial response according to RECIST was confirmed as a predictor of longer progression-free survival and overall survival.

Circulating Tumor DNA Monitoring on Chemo-immunotherapy for Risk Stratification in Advanced Non-Small Cell Lung Cancer

PURPOSE

Chemoimmunotherapy (chemoIO) is a prevalent first-line treatment for advanced driver-negative non-small cell lung cancer (NSCLC), with maintenance therapy given after induction. However, there is significant clinical variability in the duration, dosing, and timing of maintenance therapy after induction chemoIO. We used circulating tumor DNA (ctDNA) monitoring to inform outcomes in patients with advanced NSCLC receiving chemoIO.

EXPERIMENTAL DESIGN

This retrospective study included 221 patients from a phase III trial of atezolizumab+carboplatin+nab-paclitaxel versus carboplatin+nab-paclitaxel in squamous NSCLC (IMpower131). ctDNA monitoring used the FoundationOne Tracker involving comprehensive genomic profiling of pretreatment tumor tissue, variant selection using an algorithm to exclude nontumor variants, and multiplex PCR of up to 16 variants to detect and quantify ctDNA.

RESULTS

ctDNA was detected (ctDNA+) in 96% of pretreatment samples (median, 93 mean tumor molecules/mL), and similar ctDNA dynamics were noted across treatment arms during chemoIO. ctDNA decrease from baseline to C4D1 was associated with improved outcomes across multiple cutoffs for patients treated with chemoIO. When including patients with missing plasma or ctDNA- at baseline, patients with ctDNA- at C4D1 (clearance), had more favorable progression-free survival (median 8.8 vs. 3.5 months; HR, 0.32;0.20-0.52) and OS (median not reached vs. 8.9 months; HR, 0.22; 0.12-0.39) from C4D1 than ctDNA+ patients.

CONCLUSIONS

ctDNA monitoring during induction chemoIO can inform treatment outcomes in patients with advanced NSCLC. Importantly, monitoring remains feasible and informative for patients missing baseline ctDNA. ctDNA testing during induction chemoIO identifies patients at higher risk for disease progression and may inform patient selection for novel personalized maintenance or second-line treatment strategies.

Preferential B cell differentiation by combined immune checkpoint blockade for renal cell carcinoma is associated with clinical response and autoimmune reactions

Combined immune checkpoint blockade (ICB) is effective therapy for renal cell carcinoma (RCC). However, the dynamic changes in circulating B cells induced by combined ICB have not been clarified. The present study prospectively examined 22 patients scheduled to receive ICB for unresectable or metastatic RCC between March 2018 and August 2021. Eleven patients received combined therapy with anti-PD-1 (nivolumab) and anti-CTLA-4 (ipilimumab), and the other 11 patients received nivolumab monotherapy. Comprehensive phenotypes of circulating immune cells obtained prior to and after ICB therapy were analyzed by flow cytometry. Although the proportion of naïve B cells among total B cells was significantly decreased, that of switched memory B cells was significantly increased after combined therapy. In responders, the proportion of B cells among peripheral blood mononuclear cells was significantly higher prior to ICB therapy, and the proportion of switched memory B cells among total B cells tended to increase after ICB therapy. Of note, the proportion of plasmablasts among total B cells was significantly increased after ICB therapy in patients who developed severe immune-related adverse events (irAEs), and the proportion of B cells among peripheral blood decreased significantly. Furthermore, in four of five patients who developed immune-related hypophysitis following combined therapy, anti-pituitary antibody was detected in the serum. These results suggested that immune-related hypophysitis was closely related to the increase in circulating plasmablasts. Collectively, this study suggests that combined ICB promotes the differentiation of B cell populations, which is associated with efficient tumor suppression and development of irAEs.

Unraveling the Complexities of Immune Checkpoint Inhibitors in Hepatocellular Carcinoma

Immune checkpoint inhibitors (ICIs) have emerged as effective therapeutics for multiple cancers. Nevertheless, as immunotherapeutic approaches are being extensively utilized, substantial hurdles have arisen for clinicians. These include countering ICIs resistance and ensuring precise efficacy assessments of these drugs, especially in the context of hepatocellular carcinoma (HCC). This review attempts to offer a holistic overview of the latest insights into the ICIs resistance mechanisms in HCC, the molecular underpinnings, and immune response. The intent is to inspire the development of efficacious combination strategies. This review also examines the unconventional response patterns, namely pseudoprogression (PsP) and hyperprogression (HPD). The prompt and rigorous evaluation of these treatment efficacies has emerged as a crucial imperative. Multiple clinical, radiological, and biomarker tests have been advanced to meticulously assess tumor response. Despite progress, precise mechanisms of action and predictive biomarkers remain elusive. This necessitates further investigation through prospective cohort studies in the impending future.

Overall survival of patients with hepatocellular carcinoma treated with sintilimab and disease outcome after treatment discontinuation

BACKGROUND

The use of Anti-PD-1 therapy has yielded promising outcomes in hepatocellular carcinoma (HCC). However, limited research has been conducted on the overall survival (OS) of patients with varying tumor responses and treatment duration.

METHODS

This retrospective study analyzed HCC patients who received sintilimab between January 2019 and December 2020 at four centers in China. The evaluation of tumor progression was based on Response Evaluation Criteria in Solid Tumors version 1.1. The study investigated the correlation between tumor response and OS, and the impact of drug use on OS following progressive disease (PD).

RESULTS

Out of 441 treated patients, 159 patients satisfied the inclusion criteria. Among them, 77 patients with disease control exhibited a significantly longer OS compared to the 82 patients with PD (median OS 26.0 vs. 11.3 months, P < 0.001). Additionally, the OS of patients with objective response (OR) was better than that of patients with stable disease (P = 0.002). Among the 47 patients with PD who continued taking sintilimab, the OS was better than the 35 patients who discontinued treatment (median OS 11.4 vs. 6.9 months, P = 0.042).

CONCLUSIONS

In conclusion, the tumor response in HCC patients who received sintilimab affects OS, and patients with PD may benefit from continued use of sintilimab.

A Phase II Study of Durvalumab for Bacillus Calmette-Guerin (BCG) Unresponsive Urothelial Carcinoma In Situ of the Bladder

PURPOSE

Immune checkpoint blockade holds promise for treating bacillus Calmette-Guerin (BCG)-unresponsive non-muscle-invasive bladder cancer (NMIBC). In this phase II study, we investigated the safety and efficacy of durvalumab, a human IgG1 monoclonal antibody, against BCG-unresponsive carcinoma in situ (CIS).

PATIENTS AND METHODS

Patients with BCG-unresponsive CIS-containing NMIBC received durvalumab IV at 1,500 mg every 4 weeks for up to 12 months. The primary endpoint was complete response (CR) rate at month 6, defined by negative cystoscopy, urine cytology, and absence of high-grade recurrence on bladder mapping biopsy. The null hypothesis specified a CR rate of 18% and alternative hypothesis of 40%. According to the Simon two-stage design, if ≤3/13 patients achieved CR during stage 1, the trial is stopped due to futility.

RESULTS

Between March 8, 2017, and January 24, 2020, 17 patients were accrued whereas 4 withdrew from study treatment after bladder biopsy at month 3 was positive for CIS. Two of 17 (12%) achieved a CR at month 6, with duration of response of 10 and 18 months, respectively. A single grade 3 lipase elevation was attributed to durvalumab, and immune-related adverse events were observed in 7/17 (41%) patients. Only 1/17 patients had high programmed death-ligand 1 expression pretreatment. On RNA sequencing, complement activation genes were elevated posttreatment, along with enrichment of tumor-associated macrophage signature.

CONCLUSIONS

Durvalumab monotherapy conferred minimal efficacy in treating BCG-unresponsive CIS of the bladder, with 6-month CR of 12%. Complement activation is a potential mechanism behind treatment resistance.

The role of clinical imaging in oncology drug development: progress and new challenges

In 2008, the role of clinical imaging in oncology drug development was reviewed. The review outlined where imaging was being applied and considered the diverse demands across the phases of drug development. A limited set of imaging techniques was being used, largely based on structural measures of disease evaluated using established response criteria such as response evaluation criteria in solid tumours. Beyond structure, functional tissue imaging such as dynamic contrast-enhanced MRI and metabolic measures using [18F]flourodeoxyglucose positron emission tomography were being increasingly incorporated. Specific challenges related to the implementation of imaging were outlined including standardisation of scanning across study centres and consistency of analysis and reporting. More than a decade on the needs of modern drug development are reviewed, how imaging has evolved to support new drug development demands, the potential to translate state-of-the-art methods into routine tools and what is needed to enable the effective use of this broadening clinical trial toolset. In this review, we challenge the clinical and scientific imaging community to help refine existing clinical trial methods and innovate to deliver the next generation of techniques. Strong industry-academic partnerships and pre-competitive opportunities to co-ordinate efforts will ensure imaging technologies maintain a crucial role delivering innovative medicines to treat cancer.

Advanced non-small-cell lung cancer treated with first-line pembrolizumab plus chemotherapy: tumor response dynamics as a marker for survival

OBJECTIVES

The study investigated tumor burden dynamics on computed tomography (CT) scans in patients with advanced non-small-cell lung cancer (NSCLC) during first-line pembrolizumab plus chemotherapy, to provide imaging markers for overall survival (OS).

METHODS

The study included 133 patients treated with first-line pembrolizumab plus platinum-doublet chemotherapy. Serial CT scans during therapy were assessed for tumor burden dynamics during therapy, which were studied for the association with OS.

RESULTS

There were 67 responders, with overall response rate of 50%. The tumor burden change at the best overall response ranged from - 100.0% to + 132.1% (median of - 30%). Higher response rates were associated with younger age (p < 0.001) and higher programmed cell death-1 (PD-L1) expression levels (p = 0.01). Eighty-three patients (62%) showed tumor burden below the baseline burden throughout therapy. Using an 8-week landmark analysis, OS was longer in patients with tumor burden below the baseline burden in the first 8 weeks than in those who experienced ≥ 0% increase (median OS: 26.8 vs. 7.6 months, hazard ratio (HR): 0.36, p < 0.001). Tumor burden remained below their baseline throughout therapy was associated with significantly reduced hazards of death (HR: 0.72, p = 0.03) in the extended Cox models, after adjusting for other clinical variables. Pseudoprogression was noted in only one patient (0.8%).

CONCLUSIONS

Tumor burden staying below the baseline burden throughout the therapy was predictive of prolonged overall survival in patients with advanced NSCLC treated with first-line pembrolizumab plus chemotherapy, and may be used as a practical marker for therapeutic decisions in this widely used combination regimen.

CLINICAL RELEVANCE STATEMENT

The analysis of tumor burden dynamics on serial CT scans in reference to the baseline burden can provide an additional objective guide for treatment decision making in patients treated with first-line pembrolizumab plus chemotherapy for their advanced NSCLC.

KEY POINTS

• Tumor burden remaining below baseline burden during therapy predicted longer survival during first-line pembrolizumab plus chemotherapy. • Pseudoprogression was noted in 0.8%, demonstrating the rarity of the phenomenon. • Tumor burden dynamics may serve as an objective marker for treatment benefit to guide treatment decisions during first-line pembrolizumab plus chemotherapy.

Can physiologic colonic [18F]FDG uptake in PET/CT imaging predict response to immunotherapy in metastatic melanoma?

AIM

The development of biomarkers that can reliably and early predict response to immune checkpoint inhibitors (ICIs) is crucial in melanoma. In recent years, the gut microbiome has emerged as an important regulator of immunotherapy response, which may, moreover, serve as a surrogate marker and prognosticator in oncological patients under immunotherapy. Aim of the present study is to investigate if physiologic colonic [18F]FDG uptake in PET/CT before start of ICIs correlates with clinical outcome of metastatic melanoma patients. The relation between [18F]FDG uptake in lymphoid cell-rich organs and long-term patient outcome is also assessed.

METHODOLOGY

One hundred nineteen stage IV melanoma patients scheduled for immunotherapy with ipilimumab, applied either as monotherapy or in combination with nivolumab, underwent baseline [18F]FDG PET/CT. PET/CT data analysis consisted of standardized uptake value (SUV), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) calculations in the colon as well as measurements of the colon-to-liver SUV ratios (CLRmean, CLRmax). Visual grading of colon uptake based on a four-point scale was also performed. Moreover, the spleen-to-liver SUV ratios (SLRmean, SLRmax) and the bone marrow-to-liver SUV ratios (BLRmean, BLRmax) were calculated. We also measured serum lipopolysaccharide (LPS) levels as a marker for bacterial translocation and surrogate for mucosal defense homeostasis. The results were correlated with patients' best clinical response, progression-free survival (PFS), and overall survival (OS) as well as clinical signs of colitis.

RESULTS

Median follow-up [95%CI] from the beginning of immunotherapy was 64.6 months [61.0-68.6 months]. Best response to treatment was progressive disease (PD) for 60 patients, stable disease (SD) for 37 patients, partial response (PR) for 18 patients, and complete response (CR) for 4 patients. Kaplan-Meier curves demonstrated a trend for longer PFS and OS in patients with lower colonic SUV and CLR values; however, no statistical significance for these parameters as prognostic factors was demonstrated. On the other hand, patients showing disease control as best response to treatment (SD, PR, CR) had significantly lower colonic MTV and TLG than those showing PD. With regard to lymphoid cell-rich organs, significantly lower baseline SLRmax and BLRmax were observed in patients responding with disease control than progression to treatment. Furthermore, patients with lower SLRmax and BLRmax values had a significantly longer OS when dichotomized at their median. In multivariate analysis, PET parameters that were found to significantly adversely correlate with patient survival were colonic MTV for PFS, colonic TLG for PFS, and BLRmax for PFS and OS.

CONCLUSIONS

Physiologic colonic [18F]FDG uptake in PET/CT, as assessed by means of SUV, before start of ipilimumab-based treatment does not seem to independently predict patient survival of metastatic melanoma. On the other hand, volumetric PET parameters, such as MTV and TLG, derived from the normal gut may identify patients showing disease control to immunotherapy and significantly correlate with PFS. Moreover, the investigation of glucose metabolism in the spleen and the bone marrow may offer prognostic information.

Society for Immunotherapy of Cancer (SITC) clinical practice guideline on immunotherapy for the treatment of melanoma, version 3.0

Since the first approval for immune checkpoint inhibitors (ICIs) for the treatment of cutaneous melanoma more than a decade ago, immunotherapy has completely transformed the treatment landscape of this chemotherapy-resistant disease. Combination regimens including ICIs directed against programmed cell death protein 1 (PD-1) with anti-cytotoxic T lymphocyte antigen-4 (CTLA-4) agents or, more recently, anti-lymphocyte-activation gene 3 (LAG-3) agents, have gained regulatory approvals for the treatment of metastatic cutaneous melanoma, with long-term follow-up data suggesting the possibility of cure for some patients with advanced disease. In the resectable setting, adjuvant ICIs prolong recurrence-free survival, and neoadjuvant strategies are an active area of investigation. Other immunotherapy strategies, such as oncolytic virotherapy for injectable cutaneous melanoma and bispecific T-cell engager therapy for HLA-A*02:01 genotype-positive uveal melanoma, are also available to patients. Despite the remarkable efficacy of these regimens for many patients with cutaneous melanoma, traditional immunotherapy biomarkers (ie, programmed death-ligand 1 expression, tumor mutational burden, T-cell infiltrate and/or microsatellite stability) have failed to reliably predict response. Furthermore, ICIs are associated with unique toxicity profiles, particularly for the highly active combination of anti-PD-1 plus anti-CTLA-4 agents. The Society for Immunotherapy of Cancer (SITC) convened a panel of experts to develop this clinical practice guideline on immunotherapy for the treatment of melanoma, including rare subtypes of the disease (eg, uveal, mucosal), with the goal of improving patient care by providing guidance to the oncology community. Drawing from published data and clinical experience, the Expert Panel developed evidence- and consensus-based recommendations for healthcare professionals using immunotherapy to treat melanoma, with topics including therapy selection in the advanced and perioperative settings, intratumoral immunotherapy, when to use immunotherapy for patients with BRAFV600-mutated disease, management of patients with brain metastases, evaluation of treatment response, special patient populations, patient education, quality of life, and survivorship, among others.

Correlation of tumor PD-L1 expression in different tissue types and outcome of PD-1-based immunotherapy in metastatic melanoma - analysis of the DeCOG prospective multicenter cohort study ADOREG/TRIM

BACKGROUND

PD-1-based immune checkpoint inhibition (ICI) is the major backbone of current melanoma therapy. Tumor PD-L1 expression represents one of few biomarkers predicting ICI therapy outcome. The objective of the present study was to systematically investigate whether the type of tumor tissue examined for PD-L1 expression has an impact on the correlation with ICI therapy outcome.

METHODS

Pre-treatment tumor tissue was collected within the prospective DeCOG cohort study ADOREG/TRIM (CA209-578; NCT05750511) between February 2014 and May 2020 from 448 consecutive patients who received PD-1-based ICI for non-resectable metastatic melanoma. The primary study endpoint was best overall response (BOR), secondary endpoints were progression-free (PFS) and overall survival (OS). All endpoints were correlated with tumor PD-L1 expression (quantified with clone 28-8; cutoff ≥5%) and stratified by tissue type.

FINDINGS

Tumor PD-L1 was determined in 95 primary tumors (PT; 36.8% positivity), 153 skin/subcutaneous (34.0% positivity), 115 lymph node (LN; 50.4% positivity), and 85 organ (40.8% positivity) metastases. Tumor PD-L1 correlated with BOR if determined in LN (OR = 0.319; 95% CI = 0.138-0.762; P = 0.010), but not in skin/subcutaneous metastases (OR = 0.656; 95% CI = 0.311-1.341; P = 0.26). PD-L1 positivity determined on LN metastases was associated with favorable survival (PFS, HR = 0.490; 95% CI = 0.310-0.775; P = 0.002; OS, HR = 0.519; 95% CI = 0.307-0.880; P = 0.014). PD-L1 positivity determined in PT (PFS, HR = 0.757; 95% CI = 0.467-1.226; P = 0.27; OS; HR = 0.528; 95% CI = 0.305-0.913; P = 0.032) was correlated with survival to a lesser extent. No relevant survival differences were detected by PD-L1 determined in skin/subcutaneous metastases (PFS, HR = 0.825; 95% CI = 0.555-1.226; P = 0.35; OS, HR = 1.083; 95% CI = 0.698-1.681; P = 0.72).

INTERPRETATION

For PD-1-based immunotherapy in melanoma, tumor PD-L1 determined in LN metastases was stronger correlated with therapy outcome than that assessed in PT or organ metastases. PD-L1 determined in skin/subcutaneous metastases showed no outcome correlation and therefore should be used with caution for clinical decision making.

FUNDING

Bristol-Myers Squibb (ADOREG/TRIM, NCT05750511); German Research Foundation (DFG; Clinician Scientist Program UMEA); Else Kröner-Fresenius-Stiftung (EKFS; Medical Scientist Academy UMESciA).

Response Assessment of Primary Liver Tumors to Novel Therapies: an Imaging Perspective

The latest developments in cancer immunotherapy, namely the introduction of immune checkpoint inhibitors, have led to a fundamental change in advanced cancer treatments. Imaging is crucial to identify tumor response accurately and delineate prognosis in immunotherapy-treated patients. Simultaneously, advances in image acquisition techniques, notably functional and molecular imaging, have facilitated more accurate pretreatment evaluation, assessment of response to therapy, and monitoring for tumor recurrence. Traditional approaches to assessing tumor progression, such as RECIST, rely on changes in tumor size, while new strategies for evaluating tumor response to therapy, such as the mRECIST and the EASL, rely on tumor enhancement. Moreover, the assessment of tumor volume, enhancement, cellularity, and perfusion are some novel techniques that have been investigated. Validation of these novel approaches should rely on comparing their results with those of standard evaluation methods (EASL, mRECIST) while considering the ultimate outcome, which is patient survival. More recently, immunotherapy has been used in the management of primary liver tumors. However, little is known about its efficacy. This article reviews imaging modalities and techniques for assessing tumor response and survival in immunotherapy-treated patients with primary hepatic malignancies.

Imaging Follow-Up of Nonsurgical Therapies for Lung Cancer: AJR Expert Panel Narrative Review

Lung cancer continues to be the most common cause of cancer-related death worldwide. In the past decade, with the implementation of lung cancer screening programs and advances in surgical and nonsurgical therapies, the survival of patients with lung cancer has increased, as has the number of imaging studies that these patients undergo. However, most patients with lung cancer do not undergo surgical re-section, because they have comorbid disease or lung cancer in an advanced stage at diagnosis. Nonsurgical therapies have continued to evolve with a growing range of systemic and targeted therapies, and there has been an associated evolution in the imaging findings encountered at follow-up examinations after such therapies (e.g., with respect to posttreatment changes, treatment complications, and recurrent tumor). This AJR Expert Panel Narrative Review describes the current status of nonsurgical therapies for lung cancer and their expected and unexpected imaging manifestations. The goal is to provide guidance to radiologists regarding imaging assessment after such therapies, focusing mainly on non-small cell lung cancer. Covered therapies include systemic therapy (conventional chemotherapy, targeted therapy, and immunotherapy), radiotherapy, and thermal ablation.

Cardiac tamponade during pembrolizumab treatment in a patient with ovarian cancer: a case report

We present the case of a 39-year-old woman with platinum-resistant ovarian cancer who was treated with pembrolizumab. After five cycles of pembrolizumab treatment, she suddenly developed cardiac tamponade with a pleural effusion. The malignant pericardial and pleural effusion had increased, while the other malignant lesions had diminished in size. After pericardial and pleural drainage, no re-accumulation occurred. Pembrolizumab was continued and the patient did not have tumor progression for > 20 months. In some patients with pembrolizumab-induced cardiac tamponade, continuation of pembrolizumab treatment may be possible if other lesions decrease in size and the pericardial effusion can be controlled after drainage.

A Spontaneous Melanoma Mouse Model Applicable for a Longitudinal Chemotherapy and Immunotherapy Study

Mouse models that reflect human disorders provide invaluable tools for the translation of basic science discoveries to clinical therapies. However, many of these in vivo therapeutic studies are short term and do not accurately mimic patient conditions. In this study, we used a fully immunocompetent, transgenic mouse model, TGS, in which the spontaneous development of metastatic melanoma is driven by the ectopic expression of a normal neuronal receptor, mGluR1, as a model to assess longitudinal treatment response (up to 8 months) with an inhibitor of glutamatergic signaling, troriluzole, which is a prodrug of riluzole, plus an antibody against PD-1, an immune checkpoint inhibitor. Our results reveal a sex-biased treatment response that led to improved survival in troriluzole and/or anti-PD-1-treated male mice that correlated with differential CD8+ T cells and CD11b+ myeloid cell populations in the tumor-stromal interface, supporting the notion that this model is a responsive and tractable system for evaluating therapeutic regimens for melanoma in an immunocompetent setting.

Cardiothoracic complications of immune checkpoint inhibitors

A paradigm shift in cancer treatment occurred with the advent of immune checkpoint inhibitors (ICI). ICI therapy has improved tumor response and increased overall survival in patients with solid tumors and hematologic malignancies. While ICI therapy has improved overall patient outcomes in oncology, it has also introduced novel adverse effects called immune-related adverse effects (irAEs). Studies have shown that the development of irAEs is associated with improved overall survival, but certain irAEs like pneumonitis and myocarditis are life threatening, and could result in death if not identified and treated early. Therefore, it is important for radiologists to be aware of complications arising from ICI administration, especially those related to the heart and lungs as they are associated with greater mortality. This paper will review the imaging features of cardiothoracic toxicities, recurrent and chronic irAEs, and atypical tumor responses associated with irAEs.

Trial Design for Cancer Immunotherapy: A Methodological Toolkit

Immunotherapy with checkpoint inhibitors (CPIs) and cell-based products has revolutionized the treatment of various solid tumors and hematologic malignancies. These agents have shown unprecedented response rates and long-term benefits in various settings. These clinical advances have also pointed to the need for new or adapted approaches to trial design and assessment of efficacy and safety, both in the early and late phases of drug development. Some of the conventional statistical methods and endpoints used in other areas of oncology appear to be less appropriate in immuno-oncology. Conversely, other methods and endpoints have emerged as alternatives. In this article, we discuss issues related to trial design in the early and late phases of drug development in immuno-oncology, with a focus on CPIs. For early trials, we review the most salient issues related to dose escalation, use and limitations of tumor response and progression criteria for immunotherapy, the role of duration of response as an endpoint in and of itself, and the need to conduct randomized trials as early as possible in the development of new therapies. For late phases, we discuss the choice of primary endpoints for randomized trials, review the current status of surrogate endpoints, and discuss specific statistical issues related to immunotherapy, including non-proportional hazards in the assessment of time-to-event endpoints, alternatives to the Cox model in these settings, and the method of generalized pairwise comparisons, which can provide a patient-centric assessment of clinical benefit and be used to design randomized trials.

Treatment Beyond Progression After Anti-PD-1 Blockade in Hepatocellular Carcinoma

Immune checkpoint inhibitors (ICI) can induce atypical tumor responses including pseudoprogression in a subset of patients who may benefit from treatment beyond progression. While ICIs have emerged as frontline treatments for hepatocellular carcinoma (HCC) and are associated with clinical benefit in a minority of patients, it is unclear whether treatment beyond progression has utility in this disease type. In a multicenter cohort analysis, treatment beyond progression was associated with no new safety signals, objective responses in 5.8% of patients, and disease control in 44% of patients. Progression-free survival and overall survival were comparable between patients treated beyond progression and patients treated with subsequent therapies, demonstrating that treatment beyond progression was not detrimental to survival outcomes. Rather, treatment beyond progression may benefit select patients with HCC and could represent a viable strategy for maximizing treatment benefit in these patients.

SIGNIFICANCE

Treatment beyond progression with ICIs in patients with HCC is safe and may benefit a subset of patients due to later-onset tumor responses or disease stability. These findings may guide the design of trials testing ICIs in HCC and the use of treatment beyond progression in routine practice.

Integrated analysis of phase 1a and 1b randomized controlled trials; Treg-targeted cancer immunotherapy with the humanized anti-CCR4 antibody, KW-0761, for advanced solid tumors

INTRODUCTION

Regulatory T cells (Tregs) have attracted attention as a novel therapeutic target to augment the clinical efficacy of immunotherapy. We conducted phase Ia and Ib trials to examine the safety and efficacy of the anti-CCR4 antibody, KW-0761 (mogamulizumab), which may eliminate effector Tregs (eTregs). We herein overviewed the results of these trials, presented cases with a durable clinical response, and investigated factors associated with the clinical effects of KW-0761.

METHODS

Forty-nine patients with CCR4-negative solid cancers were enrolled in the phase Ia and Ib trials on KW-0761. An integral analysis of safety, clinical responses, prognosis, blood laboratory data, and cancer testis antigen-specific immune responses was performed.

RESULTS

Grade 3-4 treatment-related adverse events were reported in 21 (42.9%) out of 49 patients, all of which were manageable. A partial response and stable disease were observed in 1 and 9 patients, respectively. A durable clinical response was noted in 2 esophageal and 2 lung cancer patients. eTreg depletion in peripheral blood was confirmed in most patients, and eTreg depletion was sustained during the KW-0761 treatment. High lymphocyte levels at baseline and 2 weeks after the initiation of KW-0761 were associated with a favorable clinical outcome.

CONCLUSIONS

A durable clinical response was noted in some patients, and high lymphocyte levels before treatment initiation may be a biomarker for the efficacy of KW-0761. The synergistic effect of KW-0761 for depleting Tregs and other immunotherapies is expected in the future.

Peeling the I-Onion to Demystify Pseudoprogression

In this issue of Cancer Cell, Topp et al. analyze data from 799 patients treated with pembrolizumab beyond progression by RECIST 1.1 across six trials. Although 8.9%-24.4% of patients demonstrate a ≥30% reduction in target lesions, conversely 11%-18% of patients had a ≥20% increase. The benefits of treatment beyond progression must be carefully weighed against physical and financial toxicities.

Tumor dynamics in patients with solid tumors treated with pembrolizumab beyond disease progression

While many patients are treated beyond progression (TBP), the magnitude and duration of clinical benefit in these patients have not been fully quantified. Data from 799 patients with melanoma (n = 176), non-small cell lung cancer (NSCLC; n = 146), gastric cancer (GC; n = 87), head and neck squamous cell carcinoma (HNSCC; n = 112), clear-cell renal cell carcinoma (ccRCC; n = 51), and urothelial carcinoma (UC; n = 227) TBP were included. Patients had received pembrolizumab beyond confirmed progressive disease (PD) per RECIST v1.1. A subset of patients displays a 30% reduction in the sum of lesion diameters in the post-progression period (melanoma 24.4%, NSCLC 11.6%, 12.6% GC, 8.9% HNSCC, 15.7% ccRCC, and 13.2% UC). Most patients show stable target lesion dynamics in the post-progression period (melanoma, 64.8%; NSCLC, 72.6%; GC, 69.0%, 75.9% HNSCC, 72.5% ccRCC, 75.3% UC). Pembrolizumab generates meaningful efficacy in a subset of patients treated beyond RECIST v1.1 progression.

Intermediate endpoints as surrogates for outcomes in cancer immunotherapy: a systematic review and meta-analysis of phase 3 trials

Background

Cancer immunotherapy shows unique efficacy kinetics that differs from conventional treatment. These characteristics may lead to the prolongation of trial duration, hence reliable surrogate endpoints are urgently needed. We aimed to systematically evaluate the study-level performance of commonly reported intermediate clinical endpoints for surrogacy in cancer immunotherapy.

Methods

We searched the Embase, PubMed, and Cochrane databases, between database inception and October 18, 2022, for phase 3 randomised trials investigating the efficacy of immunotherapy in patients with advanced solid tumours. An updated search was done on July, 15, 2023. No language restrictions were used. Eligible trials had to set overall survival (OS) as the primary or co-primary endpoint and report at least one intermediate clinical endpoint including objective response rate (ORR), disease control rate (DCR), progression-free survival (PFS), and 1-year overall survival. Other key inclusion and exclusion criteria included: (1) adult patients (>18 years old) with advanced solid tumour; (2) no immunotherapy conducted in the control arms; (3) follow-up is long enough to achieve OS; (4) data should be public available. A two-stage meta-analytic approach was conducted to evaluate the magnitude of the association between these intermediate endpoints and OS. A surrogate was identified if the coefficient of determination (R2) was 0.7 or greater. Leave-one-out cross-validation and pre-defined subgroup analysis were conducted to examine the heterogeneity. Potential publication bias was evaluated using the Egger's and Begg's tests. This trial was registered with PROSPERO, number CRD42022381648.

Findings

52,342 patients with 15 types of tumours from 77 phase 3 studies were included. ORR (R2 = 0.11; 95% CI, 0.00-0.24), DCR (R2 = 0.01; 95% CI, 0.00-0.01), and PFS (R2 = 0.40; 95% CI, 0.23-0.56) showed weak associations with OS. However, a strong correlation was observed between 1-year survival and clinical outcome (R2 = 0.74; 95% CI, 0.64-0.83). These associations remained relatively consistent across pre-defined subgroups stratified based on tumour types, masking methods, line of treatments, drug targets, treatment strategies, and follow-up durations. No significant heterogeneities or publication bias were identified.

Interpretation

1-year milestone survival was the only identified surrogacy endpoint for outcomes in cancer immunotherapy. Ongoing investigations and development of new endpoints and incorporation of biomarkers are needed to identify potential surrogate markers that can be more robust than 1-year survival. This work may provide important references in assisting the design and interpretation of future clinical trials, and constitute complementary information in drafting clinical practice guidelines.

Funding

None.

A Smart Responsive Fluorescence-MR Nanoprobe for Monitoring Tumor Response to Immunotherapy

Accurately evaluating tumor responses to immunotherapy is clinically relevant. However, non-invasive, real-time visualization techniques to evaluate tumor immunotherapy are still lacking. Herein, a smart responsive fluorescence-MR dual-modal nanoprobe, QM(GP)-MZF(CP), is reported that can be targeted for cleavage by the cytotoxic T cell activation marker granzyme B and the apoptosis-related marker cysteine-aspartic acid-specific protease 3 (Caspase-3). The probe uses quinoline-malononitrile (QM), an aggregation-induced emission luminogen, and Mn-Zn ferrite magnetic nanoparticles (MZF-MNPs), a T2-weighted imaging (T2WI) contrast agent, as imaging molecules that are linked with the substrate peptides specific to granzyme B and Caspase-3. Therefore, both granzyme B and Caspase-3 can target and cleave the substrate peptides in QM(GP)-MZF(CP). Via aggregation-induced fluorescence imaging of QM and the aggregation-induced T2WI-enhanced imaging effect of MZF-MNPs, the status of T cells after tumor immunotherapy and the subsequent triggering of tumor cell apoptosis can be determined to identify tumor responsiveness to immunotherapy and thereby evaluate the effectiveness of this therapy in the early stages of treatment.

Postoperative pathological complete response in a patient with PD‑L1‑negative stage IIIB lung squamous cell carcinoma following neoadjuvant tislelizumab treatment combined with chemotherapy: A case report and literature review

The utilization of immune checkpoint inhibitors in oncological treatment has increased in recent years. The therapeutic strategy of targeting the programmed death-1 (PD-1)/programmed death-ligand 1 (PD-L1) pathway has altered the management of advanced non-small cell lung carcinoma (NSCLC). Tislelizumab, a novel anti-PD-1 monoclonal antibody developed in China, has demonstrated efficacy in treating advanced NSCLC. However, its potential role as a neoadjuvant therapy for locally advanced NSCLC has not been definitively established. Current guidelines do not specify which patient populations may gain the most benefit from neoadjuvant immunotherapy coupled with chemotherapy, nor do they indicate the optimal timing, dose or duration of adjuvant maintenance therapy post-NSCLC surgery. Similarly, data concerning the safety and practicability of surgical resection following neoadjuvant tislelizumab treatment for NSCLC remain limited. The present study describes the case of a patient diagnosed with stage IIIB NSCLC, which was initially deemed unresectable. A preoperative biopsy of the tumor mass revealed squamous cell carcinoma and a negative PD-L1 gene test. Notably, after two cycles of neoadjuvant tislelizumab treatment coupled with chemotherapy, the tumor exhibited marked shrinkage. This permitted the patient to undergo thoracoscopic radical lung cancer resection, which resulted in a pathological complete response. Postoperative pathology identified a large infiltration of lymphoplasmacytic cells and foamy histiocytes. The patient experienced grade 2 myelosuppression, a condition that was successfully addressed with the administration of recombinant human granulocyte colony-stimulating factor. The present case indicates the safety and feasibility of neoadjuvant immunotherapy integrated with chemotherapy for patients with locally advanced, PD-L1-negative NSCLC prior to surgical intervention. Moreover, the case suggests the potential of this therapeutic combination to alter the tumor microenvironment. However, the generalization of these findings necessitates further validation through randomized multicenter trials.

Development and Validation of a Predictive Model for Metastatic Melanoma Patients Treated with Pembrolizumab Based on Automated Analysis of Whole-Body [18F]FDG PET/CT Imaging and Clinical Features

BACKGROUND

Antibodies that inhibit the programmed cell death protein 1 (PD-1) receptor offer a significant survival benefit, potentially cure (i.e., durable disease-free survival following treatment discontinuation), a substantial proportion of patients with advanced melanoma. Most patients however fail to respond to such treatment or acquire resistance. Previously, we reported that baseline total metabolic tumour volume (TMTV) determined by whole-body [18F]FDG PET/CT was independently correlated with survival and able to predict the futility of treatment. Manual delineation of [18F]FDG-avid lesions is however labour intensive and not suitable for routine use. A predictive survival model is proposed based on automated analysis of baseline, whole-body [18F]FDG images.

METHODS

Lesions were segmented on [18F]FDG PET/CT using a deep-learning approach and derived features were investigated through Kaplan-Meier survival estimates with univariate logrank test and Cox regression analyses. Selected parameters were evaluated in multivariate Cox survival regressors.

RESULTS

In the development set of 69 patients, overall survival prediction based on TMTV, lactate dehydrogenase levels and presence of brain metastases achieved an area under the curve of 0.78 at one year, 0.70 at two years. No statistically significant difference was observed with respect to using manually segmented lesions. Internal validation on 31 patients yielded scores of 0.76 for one year and 0.74 for two years.

CONCLUSIONS

Automatically extracted TMTV based on whole-body [18F]FDG PET/CT can aid in building predictive models that can support therapeutic decisions in patients treated with immune-checkpoint blockade.

Efficacy and safety of preoperative immunotherapy alone followed by surgery in the treatment of advanced gastric cancer with MSI-H/dMMR or EBV-positive

BACKGROUND

At present, there is no consensus on whether preoperative immunotherapy (PIT) without chemotherapy followed by surgery could benefit patients with advanced gastric cancer (AGC). Here, we report a six-case series study to describe the safety and efficacy of PIT plus gastrectomy in patients with AGC.

METHODS

This study involved six patients with AGC who received PIT and surgery at our center between January 2019 and July 2021. Demographic characteristics, preoperative gastroscope biopsy pathology, surgical tissue pathology, radicalness of tumor resection, surgical safety, and recovery parameters were reported.

RESULTS

Six patients, including four patients with Epstein-Barr virus (EBV)-positive gastric cancer (GC) and two patients with microsatellite instability-high (MSI-H)/expression deficiency of mismatch repair (dMMR) protein GC, were enrolled in this study. Four patients experienced immunotherapy-related adverse events (irAEs), without severe adverse events (SAEs). Five patients underwent R0 resection, and one patient underwent palliative gastrectomy due to liver and hilar lymph node metastasis. Pathologic responses from the surgical tissue were observed in all patients, including two pathological complete response (pCR). No operative complications or postoperative deaths occurred. Three patients (50%) experienced mild or moderate postoperative complications without severe postoperative complications. All six patients eventually recovered and were discharged.

CONCLUSION

This study indicated that PIT was effective and tolerant in some patients with MSI-H/dMMR and/or EBV-positive AGC. PIT followed by gastrectomy might be an alternative treatment option for these selected patients.

Efficacy of Immune Checkpoint Inhibition and Cytotoxic Chemotherapy in Mismatch Repair-Deficient and Microsatellite Instability-High Pancreatic Cancer: Mayo Clinic Experience

PURPOSE

Pancreatic cancer (PC) carries a poor prognosis with high rates of unresectable/metastatic disease at diagnosis, recurrence after resection, and few systemic therapy options. Deficient mismatch repair (dMMR)/high microsatellite instability (MSI-H) PCs demonstrated uncharacteristically poor outcomes in KEYNOTE-158, evaluating pembrolizumab in MSI-H solid tumors. Our study aggregates the Mayo Clinic experience with dMMR/MSI-H PCs, characterizing the clinical, molecular, and treatment response patterns with a focus on response to immune checkpoint inhibitors (ICIs).

METHODS

Retrospective data were collected from the electronic medical record from December 2009 to February 2023. Patients were included if they had a pathologically confirmed pancreatic malignancy and had (1) deficient expression of mismatch repair (MMR) proteins by tumor immunohistochemistry, (2) pathogenic mutation of MMR genes on genomic sequencing, and/or (3) MSI-H by polymerase chain reaction.

RESULTS

Thirty-two patients were identified for inclusion, with all stages of disease represented. Sixteen of these patients underwent surgery or chemoradiotherapy. Of these patients, uncharacteristically favorable responses were seen, with a recurrence rate of only 19% (n = 3) despite a median follow-up of 25 months. In the palliative setting, excellent responses to ICI were seen, with overall response rate (ORR) of 75% (20% complete response). Median time to disease progression was not reached. Response rates to cytotoxic chemotherapy in the palliative setting were poor, with 30% ORR and median time to progression of 4 months. We observed a high rate of discrepancy between MMR and MSI testing methods, representing 19% of the entire cohort and 26% of evaluable cases.

CONCLUSION

Our data argue for the preferential use of ICI over cytotoxic chemotherapy in any patient with dMMR/MSI-H PC requiring systemic therapy, including in the metastatic and adjuvant/neoadjuvant settings.

An Italian multicenter retrospective real-life analysis of patients with brain metastases from renal cell carcinoma: the BMRCC study

BACKGROUND

The treatment of patients with brain-spread renal cell carcinoma (RCC) is an unmet clinical need, although more recent therapeutic strategies have significantly improved RCC patients' life expectancy. Our multicenter, retrospective, observational study investigated a real-world cohort of patients with brain metastases (BM) from RCC (BMRCC).

PATIENTS AND METHODS

A total of 226 patients with histological diagnosis of RCC and radiological evidence of BM from 22 Italian institutions were enrolled. Univariate and multivariate models were performed to investigate the impact of clinicopathological features and multimodal treatments on both overall survival (OS) from the BM diagnosis and intracranial progression-free survival (iPFS).

RESULTS

The median OS from the BM diagnosis was 18.8 months (interquartile range: 6.2-43 months). Multivariate analysis confirmed the following as positive independent prognostic factors: a Karnofsky Performance Status >70% [hazard ratio (HR) = 0.49, 95% confidence interval (CI) 0.26-0.92, P = 0.0026] and a single BM (HR = 0.51, 95% CI 0.31-0.86, P = 0. 0310); in contrast, the following were confirmed as worse prognosis factors: progressive extracranial disease (HR = 1.66, 95% CI 1.003-2.74, P = 0.00181) and only one line of systemic therapy after the BM occurrence (HR = 2.98, 95% CI 1.62-5.49, P = 0.029). Subgroup analyses showed no difference in iPFS according to the type of the first systemic treatment [immunotherapy (IT) or targeted therapy (TT)] carried out after the BM diagnosis (HR = 1.033, 95% CI 0.565-1.889, P = 0.16), and revealed that external radiation therapy (eRT) significantly prolonged iPFS when combined with IT (10.7 months, 95% CI 4.9-48 months, P = 0.0321) and not when combined with TT (9.01 months, 95% CI 2.7-21.2 months, P = 0.59).

CONCLUSIONS

Our results suggest a potential additive effect in terms of iPFS for eRT combined with IT and encourage a more intensive multimodal therapeutic strategy in a multidisciplinary context to improve the survival of BMRCC patients.

Pseudoprogression of thoracic tumor after radiotherapy in the era of immunotherapy: a case series

Pseudoprogression is rarely mentioned after radiotherapy except for central nervous system tumors. With the widespread of immunotherapy, the incidence of pseudoprogression of thoracic tumor after radiotherapy is increasing. This study summarized the clinical features of pseudoprogression in 4 patients who had underwent thoracic radiotherapy after and/or followed by immunotherapy. All of them had received chemotherapy and immunotherapy before thoracic radiotherapy. After radiotherapy, pseudoprogression occurred within 3 months after initiation of immune consolidation/rechallenge therapy. At least a 20% increase in the sum of the longest diameter of target lesions were measured on their chest image. During this period, patients' ECOG PS scores remained stable, specific serum tumor markers did not increase significantly. Treatment strategies did not change after pseudoprogression. The causes of radiographic pseudoprogression in this case series may be attributed to disturbances such as pneumonitis, atelectasis, mucus blockages and infection. In the era of immunotherapy, pseudoprogression of thoracic tumors after chest radiotherapy might become a common phenomenon. It is important for us to identify pseudoprogression based on patient's general status, radiological changes, and laboratory tests.

Dissociated response to PD-1 inhibitors combined with radiotherapy in patients with advanced metastatic solid tumors: a single-center experience

BACKGROUND

Anti-programmed death 1/anti-programmed death ligand 1 (PD-1/PD-L1) combined with radiotherapy (RT) has a synergistic effect on systemic tumor control. A dissociated response (DR), characterized by some lesions shrinking and others growing, has been recognized with immune checkpoint inhibitor (ICI) monotherapy or combination therapy. The objective of this study was to assess the frequency and clinical benefit of DR in patients with advanced metastatic solid tumors receiving PD-1 inhibitors in combination with RT.

METHODS

We conducted a single-center retrospective analysis of patients with advanced metastatic solid tumors receiving PD-1 inhibitor combined with RT at the Department of Radiotherapy & Oncology, The Second People's Hospital Affiliated with Soochow University. Treatment response was assessed for each measurable lesion according to the Response Evaluation Criteria in Solid Tumours ( RECIST) v 1.1 guidelines. Patterns of response are divided into four groups: (1) DR, (2) uniform response, (3) uniform progression, and (4) only stable lesions. The overall survival (OS) of different groups was compared using Kaplan-Meier methods and log-rank tests.

RESULTS

Between March 2019 and July 2022, 93 patients were included. The median follow-up was 10.5 months (95% CI 8.8-12.1). The most common tumor types were lung cancer (19.8%), colorectal adenocarcinoma (17.2%), and esophageal cancer (10.8%). DR was observed in 22 (23.7%) patients. The uniform progression and DR are two different patterns of progression. After confirming progression, the overall survival of patients with DR was significantly longer than that of patients with uniform progression (9.9 months (95%CI 5.7-14.1) vs. 4.2 months (95%CI 1.9-6.5), P = 0.028). Compared with DR patients who did not continue PD-1 inhibitor combined with RT or PD-1 inhibitor monotherapy (n = 12), DR patients who continued treatment (n = 10) had significantly longer OS (15.7 (95%CI 3.5-27.9) vs 8.2 (95%CI 5.6-10.8) months, P = 0.035).

CONCLUSIONS

DR is not uncommon (23.7%) in patients with advanced metastatic solid tumors treated with PD-1 inhibitors combined with RT and shows a relatively favorable prognosis. Some patients with DR may benefit from continued PD-1 inhibitor therapy in combination with RT or PD-1 inhibitor monotherapy and may have longer OS.

Monitoring Sarcoma Response to Immune Checkpoint Inhibition and Local Cryotherapy with Circulating Tumor DNA Analysis

PURPOSE

Immune checkpoint inhibition has led to promising responses in soft tissue sarcomas (STS), but the majority of patients do not respond and biomarkers of response will be crucial. Local ablative therapies may augment systemic responses to immunotherapy. We evaluated circulating tumor DNA (ctDNA) as a biomarker of response in patients treated on a trial combining immunotherapy with local cryotherapy for advanced STS.

PATIENTS AND METHODS

We enrolled 30 patients with unresectable or metastatic STS to a phase II clinical trial. Patients received ipilimumab and nivolumab for four doses followed by nivolumab alone with cryoablation performed between cycles 1 and 2. The primary endpoint was objective response rate (ORR) by 14 weeks. Personalized ctDNA analysis using bespoke panels was performed on blood samples collected prior to each immunotherapy cycle.

RESULTS

ctDNA was detected in at least one sample for 96% of patients. Pretreatment ctDNA allele fraction was negatively associated with treatment response, progression-free survival (PFS), and overall survival (OS). ctDNA increased in 90% of patients from pretreatment to postcryotherapy, and patients with a subsequent decrease in ctDNA or undetectable ctDNA after cryotherapy had significantly better PFS. Of the 27 evaluable patients, the ORR was 4% by RECIST and 11% by irRECIST. Median PFS and OS were 2.7 and 12.0 months, respectively. No new safety signals were observed.

CONCLUSIONS

ctDNA represents a promising biomarker for monitoring response to treatment in patients with advanced STS, warranting future prospective studies. Combining cryotherapy and immune checkpoint inhibitors did not increase the response rate of STS to immunotherapy.

Predictive value and accuracy of [18F]FDG PET/CT modified response criteria for checkpoint immunotherapy in patients with advanced melanoma

PURPOSE

Immune checkpoint inhibitors (ICIs) are widely used in metastatic melanoma and dramatically alter the treatment of these patients. Given the high cost and potential toxicity, a reliable method for evaluating treatment response is needed. In this study, we assessed tumor response in patients with metastatic melanoma treated with ICIs using three modified response criteria: PET Response Evaluation Criteria for Immunotherapy (PERCIMT), PET Response Criteria in Solid Tumors for up to Five Lesions (PERCIST5), and immunotherapy-modified PET Response Criteria in Solid Tumors for up to Five Lesions (imPERCIST5).

METHODS

Ninety-one patients with non-resectable stage IV metastatic melanoma who received ICIs were retrospectively enrolled in this study. Each patient had two [18F]FDG PET/CT scans performed before and after ICI therapy. Responses at the follow-up scan were evaluated according to PERCIMT, PERCIST5, and imPERCIST5 criteria. Patients were classified into four groups: complete metabolic response (CMR), partial metabolic response (PMR), progressive metabolic disease (PMD), and stable metabolic disease (SMD). To assess the "disease control rate," two groups have been defined based on each criterion: patients with CMR, PMR, and SMD as "disease-controlled group (i.e., responders)" and PMD as the "uncontrolled-disease group (i.e., non-responders)". The correspondence between metabolic tumor response defined by these criteria and clinical outcome was assessed and compared.

RESULTS

The response and the disease control rates were 40.7% and 71.4%, 41.8% and 50.5%, and 54.9% and 74.7% based on the PERCIMT, PERCIST5, and imPERCIST5 criteria, respectively. PERCIMT and imPERCIST5 showed significantly different disease control rates from that of PERCIST5 (P < 0.001), whereas it was not significant between PERCIMT and imPERCIST5. Overall survival was significantly longer in the metabolic responder groups than in the non-responder groups based on PERCIMT and PERCIST5 criteria (PERCIMT: 2.48 versus 1.47 years, P = 0.003; PERCIST5: 2.57 versus 1.81 years. P = 0.017). However, according to imPERCIST5 criterion, this difference was not observed (P = 0.12).

CONCLUSION

Although the appearance of new lesions can be secondary to an inflammatory response to ICIs and indicative of pseudoprogression, given the higher rate of true progression, the appearance of new lesions should be interpreted deliberately. Of the three assessed modified criteria, PERCIMT appear to provide more reliable metabolic response assessment that correlates strongly with overall patient survival.

Comparison of RECIST and iRECIST criteria in patients with advanced lung cancer treated with nivolumab

Background

Systemic therapy in lung cancer is mainstay of treatment as most patients present in advanced stages, with rising importance of new immunotherapy agents.

Purpose

To compare the RECIST 1.1 and the immunotherapy Response Evaluation Criteria in Solid Tumors (iRECISTs) criteria for response assessment in lung cancer patients on immunotherapy. To find the incidence of pseudoprogression and associated imaging patterns.

Material and Methods

Retrospective study in 28 patients treated with immunotherapy for advanced metastatic NSCLC. End points were progression-free survival (PFS) and overall survival (OS). Response assessments were separately tabulated according to RECIST 1.1 and iRECIST and classified into dichotomous groups of responders and nonresponders. Agreement in assessments between RECIST 1.0 and iRECIST examined using Cohen kappa (κ) coefficient with 95% confidence intervals. Kaplan-Meier survival analysis was done for PFS and OS. Differences between RECIST 1.1 and iRECIST for both responder and nonresponder were evaluated by the log rank test, Breslow (Generalized Wilcoxon) test, and Tarone-Ware test.

Results

Incidence of pseudoprogression was 7% (2/28). The RECIST1.1 and iRECIST were in disagreement in two patients. The agreement between RECIST and iRECIST was almost perfect. The PFS and the OS are significantly longer in duration for responders in comparison to nonresponders for both RECIST and iRECIST and the difference between two assessment criteria is not significant.

Conclusion

Although iRECIST aims to monitor treatment more precisely than conventional response criteria, this must be weighed against how infrequent pseudoprogression is and the cost of this therapy, both financially and in the potential delay in changing to a more effective treatment.

Immuno-PET Imaging of CD69 Visualizes T-Cell Activation and Predicts Survival Following Immunotherapy in Murine Glioblastoma

Glioblastoma (GBM) is the most common and malignant primary brain tumor in adults. Immunotherapy may be promising for the treatment of some patients with GBM; however, there is a need for noninvasive neuroimaging techniques to predict immunotherapeutic responses. The effectiveness of most immunotherapeutic strategies requires T-cell activation. Therefore, we aimed to evaluate an early marker of T-cell activation, CD69, for its use as an imaging biomarker of response to immunotherapy for GBM. Herein, we performed CD69 immunostaining on human and mouse T cells following in vitro activation and post immune checkpoint inhibitors (ICI) in an orthotopic syngeneic mouse glioma model. CD69 expression on tumor-infiltrating leukocytes was assessed using single-cell RNA sequencing (scRNA-seq) data from patients with recurrent GBM receiving ICI. Radiolabeled CD69 Ab PET/CT imaging (CD69 immuno-PET) was performed on GBM-bearing mice longitudinally to quantify CD69 and its association with survival following immunotherapy. We show CD69 expression is upregulated upon T-cell activation and on tumor-infiltrating lymphocytes (TIL) in response to immunotherapy. Similarly, scRNA-seq data demonstrated elevated CD69 on TILs from patients with ICI-treated recurrent GBM as compared with TILs from control cohorts. CD69 immuno-PET studies showed a significantly higher tracer uptake in the tumors of ICI-treated mice compared with controls. Importantly, we observed a positive correlation between survival and CD69 immuno-PET signals in immunotherapy-treated animals and established a trajectory of T-cell activation by virtue of CD69-immuno-PET measurements. Our study supports the potential use of CD69 immuno-PET as an immunotherapy response assessment imaging tool for patients with GBM.

Significance

Immunotherapy may hold promise for the treatment of some patients with GBM. There is a need to assess therapy responsiveness to allow the continuation of effective treatment in responders and to avoid ineffective treatment with potential adverse effects in the nonresponders. We demonstrate that noninvasive PET/CT imaging of CD69 may allow early detection of immunotherapy responsiveness in patients with GBM.