Early Marker Of Response Research Articles

Utilizing CLL-1 Positive Leukemia Stem Cells As a Marker of Early Treatment Response in Acute Myeloid Leukemia

Background: Current methods to evaluate therapeutic response in Acute Myeloid leukemia (AML) rely primarily on morphological evaluation of leukemia blasts in bone marrow at end of treatment cycles, with complete remission (CR) defined as less than 5% bone marrow blast counts without leukemic phenotype. Measurable residual disease (MRD) has been shown highly prognostic for outcome. MRD by molecular methods is limited to subgroup of patients with defined genetic mutations. MRD detection by Multicolor Flow Cytometry (MFC) is still being standardized. Leukemia stem cells (LSC) has been established as source of treatment resistance and disease recurrence in AML. In this study, we aim to analyze change in LSC during treatment using immunophenotypically defined markers and examine whether information gained from LSC analysis could provide additional insights into disease course and assist management of AML under routine clinical practice setting. Methods: We analyzed flow cytometry data from bone marrow aspirate (BMA) and/or peripheral blood (PB) in patients with AML (excluding acute promyelocytic leukemia) before and after treatment. "Leukemic blasts” were identified by morphology and Leukemia-associated Immunophenotype by MFC. Hematopoietic stem cells (HSCs) gating was based on CD45dim/SSC and CD34+CD38low/- expression. Leukemic stem cells (LSC) fractional change was analyzed using CD371 (CLL-1), CD366 (TIM3), and CD45RA percent of positive over HSCs. A chart review was conducted to determine correlation between LSC fractional change and clinical outcome. Statistical analysis was performed using GraphPad Prism version 9. Results: Fifty AML cases with both pre- and post-treatment data from a single institution in the past 3 years were included in this study. Consistent with published literature, patients with significant reduction in LSC subsets was associated with longer remission, while patients with no significant decrease in the LSC subsets demonstrated no or only a temporary remission. Intriguingly, several patients with drastic reduction in LSC after induction chemotherapy achieved complete remission, despite initial post-treatment bone marrow showing persistence of ">5% leukemia blasts” indicating possibly failed induction therapy. In contrast, in patients with persistently high or increased LSC fraction post-treatment, overt clinical relapse occurred quickly despite "absence” or <1% of leukemia blast differential counts in initial bone marrow. In a series of patients who received allogeneic stem cell transplant (Allo-SCT), rise of LSC fraction post Allo-SCT was associated with early AML relapse (within 6 months), while the decrease of LSC fraction was associated with prolonged remission (Representative patient cases shown in Figure 1). Lastly, among the three LSC-specific markers analyzed, the changes in LSC characterized by CLL-1 expression showed the best correlation with clinical course. In addition, the LSC fraction measured by CLL-1 in the peripheral blood is highly correlated with that of the bone marrow (R2=0.93, P<0.0001). Conclusion: This retrospective study explored the value and applicability of LSC detection in routine clinical practice. Importantly, conventional methods relying on evaluating leukemic blast counts in post-treatment bone marrow can sometimes over- or under- estimate the benefit of certain treatment regimen, leading to inappropriate continuation of the same treatment or switch of a potentially effective treatment regimen. In those groups of patients, the change in LSC fraction provides additional information for early treatment response evaluation, refines outcome prediction, and helps with treatment regimen selection. Trending LSC fractional change identifies impending relapse in post Allo-SCT. LSC fractional change determined by CLL-1 showed the best clinical correlation and should be incorporated into routine evaluation for AML patient in clinical practice, and possibly for those participating in investigational trials. Future studies will focus on collecting more data to validate above findings, determining the thresholds of LSC fractional change which constitute potential treatment response vs failure and testing the feasibility of tracking LSC subsets non-invasively in peripheral blood during treatment to predict therapeutic outcome and potentially guide treatment decisions. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Serum Level Kinetic of Key Cytokines in Newly Diagnosed Lymphoma Patients during First Line Treatment: Correlation with PET/CT Scan Results and Treatment Outcome

Background: Cytokines are soluble proteins that play a key role in mediating and regulating inflammation and immune responses. Further, they are involved in lymphoid development and differentiation, as well as in lymphoid tumorigenesis. Aim of the present study was to verify if the serum-cytokine levels could be an early marker of treatment response. With this purpose, we analyzed the serum concentration kinetic of key cytokines in diffuse large B-cell lymphoma (DLBCL), follicular lymphoma (FL) and Hodgkin lymphoma (HL) pts comparing it with PET/CT scan results and treatment outcome. Patients and Methods: After Ethic Committee approval, we start to enroll lymphoma pts treated at Modena Cancer Center. Until now, 29 patients entered the study, including 12 pts with DLBCL, 11 with FL, and 6 with HL. DLBCL lymphoma were treated with R-CHOP and FL patients with R-CVP or R-Benda or R-CHOP, while HL patients with ABVD + ABVD or BEACOP following indications of intermediate PET. A panel of eight serum cytokines/chemokines (IL6, IL2, IL8, IL10, IFNγ, TNFα, CXCL10/IPI10, CCL17/TARC) was analyzed using the Simple Plex system (Protein Simple, San Jose, CA, USA) according to the manufacturer's recommendations. Serum samples were collected at the day of staging (PET-0), at the day of intermediate PET (I-PET) and at the day of end treatment PET (EOT-PET). Samples were analyzed in duplicate. Continuous variables were compared by Mann-Whitney test and categorical variables by Chi2 test. Matched data were analyzed by paired Wilcoxon or Friedman test. Statistical significance was defined as p < 0.05. Results: The median age of all 29 pts was 60 yr (range 21-86), and 65 % were male. Patients with HL were younger (50 yr) than pts with FL (61 yr) and DLBCL (68 yr). In all 29 pts, median concentration of IL10, IL6, TNFα at EOT-PET decreased in comparison with the levels at PET-0, while IFNγ and IPI10 increased. IL8 increased in DLBCL and in HL, while decreased in FL. IL2 levels did not show relevant changes. No statistically significant differences were found between the concentrations of these cytokines at PET-0 and EOT-PET. The mean serum TARC level at PET-0 were 854 pg/mL (range 130-5829), 1209 pg/mL (range 134-6903) and 8327 pg/mL (range 6488-10885) in DLBC, FL and HL pts, respectively. At EOT-PET the mean concentration of TARC were 562 pg/mL (range 130-854) (p=0.49), 989 pg/mL (range 134-6903) (p=0.74), 591 pg/mL (range 353-932) (p=0.03 ) in DLBCL, FL and HL pts, respectively. In HL patients, TARC values were significantly lower at I-PET with a mean of 525 pg/mL (range 210-1062) compared to PET-0 (p=0.016), with a p value along the 3 timepoint =0.009. EOT-PET and I-PET, evaluated by Deauville score shows that almost all patients achieved CR at the end of treatment: 11 out of 12 DLBCL pts have a Deauville score between 1 and 3, as well as all FL and HL pts. Only 1 DLBCL patient had a Deauville score of 4 at the end of treatment, achieving CR after further radiotherapy. Conclusion: Our study, despite the limitations due to the small number of pts enrolled to date, shows that the concentrations of cytokines/chemokines, with the exception of TARC, do not undergo significant changes, before and after first-line therapy. The TARC values, on the other hand, correlate well with the results of PET/CT and therefore also with the response to therapy in all subtypes of lymphoma. This correlation is statistically significant in pts with HL. TARC assessment could therefore become a useful, inexpensive and easy to determine predictive marker of response to therapy and may be important for determining treatment strategy in lymphoma patients. Further, the TARC levels assessed during the follow-up could be early markers of relapse. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Integrated genome-wide methylation and expression analyses provide predictors of diagnosis and early response to antidepressant in panic disorder

BackgroundWe investigated differentially methylated and expressed genes between panic disorder (PD) and healthy controls (HCs) to determine whether DNA methylation and expression level of candidate genes can be used as biomarkers for diagnosis and early response. MethodsIllumina infiniun Methylation EPIC (850 k) Beadchip for genome-wide methylation screening and mRNA sequencing was conducted in a discovery set (30 patients with PD and 30 matched HCs). The candidate gene loci methylation and expression were verified in an independent validation sample (101 PD patients and 107 HCs). ResultsIn the discovery set, there were 3613 differentially methylated cytosine phosphate guanosine sites and these differential methylation positions were located within 1938 unique genes, including 1758 hypermethylated genes, 150 hypomethylated genes, and the coexistence of hypermethylation and hypomethylation sites were found in 30 genes. There were 1111 differential transcripts in PD compared to normal controls (850 down-regulated and 261 up-regulated). Further, 212 differentially expressed genes were screened (40 up-regulated and 172 down-regulated). In the validation set, compared with HCs, there was no significant difference in DNA methylation level of Casitas B-lineage lymphoma (CBL) gene loci (cg07123846). The expression level of CBL gene in PD patients was lower (vs. HCs). After four weeks' treatment, the baseline expression level of CBL gene in the responders was higher than nonresponders. LimitationsThe sample size was limited. We only chose CBL as a candidate gene. Follow-up periods were short. ConclusionsThere are differences in genome-wide DNA methylation and mRNA expression between PD patients and HCs. The changes in expression level of CBL gene may be an important molecular marker for PD diagnosis and early response.

Change over time and agreement between clinical markers of disease resolution in dogs with aspiration-induced lung injury.

There is a lack of consensus regarding which markers of disease resolution to prioritise when assessing treatment response in client-owned dogs with aspiration-induced lung injury. This study describes the change over time and the agreement between the clinical markers used to determine disease resolution. Physical examination (PE), owner-reported clinical signs (CS-O), thoracic radiographs (TXR) scores and C-reactive protein (CRP) concentrations were determined at enrolment, after 24, 48 and 72 hours, and after 7, 14 and 28 days. PE scores were significantly improved at 48 hours, while CRP initially increased (24 hours) and then decreased (48 hours). PE, CS-O and CRP significantly improved earlier (7 days) than TXR (14 days). The median number of days to marker normalisation was 7, 9 and 14 for PE, CRP and CS-O, respectively. Marker agreement was excellent/very good at enrolment and fair/poor during disease recovery. Analysis did not control for differences aetiology of aspiration or the lack of standardisation in treatment approach. PE was the earliest and most consistent marker indicating disease resolution. Serial CRP monitoring (72 hours) may provide an objective marker of early treatment response. Alongside PE normalisation, improvement in CS-O, CRP and TRX may assist in determining disease resolution and guide treatments, including limiting antibiotic exposure in dogs with aspiration-induced lung injury.

Prognostic Role of Post-Induction Fecal Calprotectin Levels in Patients with Inflammatory Bowel Disease Treated with Biological Therapies.

Background: There is currently scarce knowledge about markers of early therapeutic response in patients with inflammatory bowel disease (IBD) treated with biologics. The aim of this study was to evaluate the role of fecal calprotectin (FC) as an early predictor of mucosal healing and clinical remission. Methods: Data from a multicenter series of 172 IBD patients treated with biologics between 2017 and 2020 were analyzed. Treatment outcomes were mucosal healing and clinical remission assessed at 2 years. FC levels were assessed at 14 weeks (post-induction), at 6 months, and yearly. The receiver operating characteristic (ROC) curve analysis was performed to calculate the best cut-off in % change of FC levels between post-induction and baseline predicting treatment outcomes. Sensitivity, specificity, and accuracy for several post-induction FC cut-off points were also calculated. Results: At 2 years, mucosal healing was noted in 77 patients (44.7%), of whom were 41 Crohn’s disease (CD) and 36 ulcerative colitis (UC) patients, whereas 106 patients experienced clinical remission (61.6%), of whom were 59 CD and 47 UC patients. Both baseline and post-induction FC levels were significantly higher in non-responders as compared to responders. On the other hand, FC decrease was less pronounced in non-responders. Similar results were observed in all subgroups, namely according to disease (CD vs. UC), or treatment used (TNF-inhibitors vs. vedolizumab). The best cut-off points were −86% in % change in FC levels to predict mucosal healing and −83% for clinical remission. Conclusions: The current study suggests a predictive role of post-induction FC assessment to predict treatment response in IBD patients treated with biologics.

Chemotherapy response evaluation using diffusion weighted MRI in Ewing Sarcoma: A single center experience.

Non-invasive biomarkers for early chemotherapeutic response in Ewing sarcoma family of tumors (ESFT) are useful for optimizing existing treatment protocol. To assess the role of diffusion-weighted magnetic resonance imaging (MRI) in the early evaluation of chemotherapeutic response in ESFT. A total of 28 patients (mean age = 17.2 ± 5.6 years) with biopsy proven ESFT were analyzed prospectively. Patients underwent MRI acquisition on a 1.5-T scanner at three time points: before starting neoadjuvant chemotherapy (baseline), after first cycle chemotherapy (early time point), and after completion of chemotherapy (last time point). RECIST 1.1 criteria was used to evaluate the response to chemotherapy and patients were categorized as responders (complete and partial response) and non-responders (stable and progressive disease). Tumor diameter, absolute apparent diffusion coefficient (ADC), and normalized ADC (nADC) values in the tumor were measured. Baseline parameters and relative percentage change of parameters after first cycle chemotherapy were assessed for early detection of chemotherapy response. The responder:non-responder ratio was 21:7. At baseline, ADC ([0.864 ± 0.266 vs. 0.977 ± 0.246]) × 10-3mm2/s; P = 0.205) and nADC ([0.740 ± 0.254 vs. 0.925 ± 0.262] × 10-3mm2/s; P = 0.033) among responders was lower than the non-responders and predicted response to chemotherapy with AUCs of 0.6 and 0.735, respectively. At the early time point, tumor diameter (27% ± 14% vs. 4.6% ± 10%; P = 0.002) showed a higher reduction and ADC (75% ± 44% vs. 52% ± 72%; P = 0.039) and nADC (81% ± 44% vs. 48% ± 67%; P = 0.008) showed a higher increase in mean values among responders than the non-responders and identified chemotherapy response with AUC of 0.890, 0.723, and 0.756, respectively. Baseline nADC and its change after the first cycle of chemotherapy can be used as non-invasive surrogate markers of early chemotherapeutic response in patients with ESFT.

Current Treatment and Future Trends of Immunotherapy in Breast Cancer.

Immunotherapy continues to redefine the solid tumor treatment landscape, with inhibitors of the PD-L1/PD-1 immune checkpoint having the most widespread impact. As the most common cancer diagnosed worldwide, there is significant interest in the development of immunotherapy for the treatment of breast cancer in both the early and metastatic settings. Recently reported results of several clinical trials have identified potential roles for immunotherapy agents alone or in combination with standard treatment for early and metastatic disease. While trials to date have been promising, immunotherapy has only been shown to benefit a select group of patients with breast cancer, defined by tumor subtype, PD-L1 expression, and line of therapy. With over 250 trials ongoing, emerging data will enable the further refinement of breast cancer immunotherapy strategies. The integration of multiple putative biomarkers and consideration of dynamic markers of early response or resistance may inform optimal patient selection for immunotherapy investigation and integration into clinical practice. This review will summarize the current evidence for immune-checkpoint blockade (ICB) in the treatment of early and metastatic breast cancer, highlighting current and potential future biomarkers of therapeutic response.

Baricitinib therapy response in rheumatoid arthritis patients associates to STAT1 phosphorylation in monocytes.

Baricitinib is a Janus kinase (JAK) 1 and 2 inhibitor approved for treating rheumatoid arthritis (RA). The JAK/STAT system is essential in the intracellular signaling of different cytokines and in the activation process of the monocyte lineage. This study verifies the effects of baricitinib on STAT phosphorylation in monocytes of RA patients and evaluates the correlation between STAT phosphorylation and response to therapy. We evaluated the disease activity of patients (DAS28CRP) at baseline (T0) and after 4 and 12 weeks (T1–T3) of treatment with baricitinib, dividing them into responders (n = 7) and non-responders (n = 7) based on the reduction of DAS28CRP between T0 and T1 of at least 1.2 points. Through flow cytometry, STAT1 phosphorylation was analyzed at T0/T1/T3 in monocytes, at basal conditions and after IL2, IFNα, and IL6 stimulation. We showed that monocyte frequency decreased from T0 to T1 only in responders. Regarding the phosphorylation of STAT1, we observed a tendency for higher basal pSTAT1 in monocytes of non-responder patients and, after 4 weeks, a significant reduction of cytokine-induced pSTAT1 in monocytes of responders compared with non-responders. The single IFNα stimulation only partially recapitulated the differences in STAT1 phosphorylation between the two patient subgroups. Finally, responders showed an increased IFN signature at baseline compared with non-responders. These results may suggest that monocyte frequency and STAT1 phosphorylation in circulating monocytes could represent early markers of response to baricitinib therapy.

Abstract CT107: Correlation of biomarkers and clinical benefit of intratumoral BO112 and pembrolizumab in patients with anti PD1 refractory melanoma

Abstract Background: There is a lack of predictive biomarkers for immunotherapy in melanoma. In terms of IHC, there is no strong rational to support the use of PD-L1 expression. BRAF mutations occur in 40-50% of melanomas and the MAPK pathway may also be activated by NRAS mutations. Patients harboring these mutations face usually a worse prognosis. BO-112 is a double stranded synthetic RNA formulated with polyethyleneimine (PEI) that, by mimicking the effect of a viral infection, mobilizes the immune system. Prior data from a phase I trial (NCT02828098) suggest that, when administered intratumorally, it causes an increase in CD8 infiltration and PD-L1 expression. The role of these and other biomarkers is being explored in the present phase II clinical trial. Study Design: Single arm study with BO-112 plus pembrolizumab (NCT04570332) in patients with advanced melanoma in progression to anti-PD1 therapy. Tumors were genotyped by next generation sequencing, whole exome sequencing and tumor mutation burden. Antitumor and immunological effects of the treatment in the tumor microenvironment were assessed by PDL1 and CD8 immunohistochemistry with a paired biopsy performed after 21 days of treatment. Results: A preliminary analysis has been performed, based on patients evaluable for clinical benefit (defined as response or stable disease&amp;gt;16 weeks). Samples from 35 patients have been analyzed, with 24 patients paired biopsies available. Patients with “cold” tumors (PD-L1 negative and CD8 low) at baseline had a trend to lack of clinical benefit. Only basal PD-L1 in the inflammatory component showed a statistically significant correlation with clinical outcome (4/20 (25%) tumors PDL1 IC negative had benefit versus 10/15 (67%) positive), p=0.0053. Fifteen patients had an increase in PD-L1 and 14 patients had increase in CD8 infiltrate after BO-112 treatment; the lack of increase in PDL1 and CD8 after treatment was also predictive of lack of response (p=0.04). BRAF/NRAS driver mutations correlated with positive outcome. Clinical benefit was observed in 4 of 17 (24%) patients not carrying activating mutations whereas 11 out of 18 (61%) patients with BRAF/NRAS activating mutations had clinical benefit (p=0.02), mainly in cutaneous histology (14% versus 65%, p=0.02). Mucosal melanoma patients (n=3) achieved an ORR 66.7% and DCR 100%. The two mucosal melanoma patients with partial response harbored SETD2 mutations and one of them showed extensive cyclic nucleotide-gated (CNGs), indicative of defects in DNA repair pathways. Regarding acral melanoma patients (n=9), no responses were observed, even in the single case with a NRAS mutation. The only patient achieving clinical benefit, with stable disease&amp;gt;16 weeks; had a unique mutation profile, with TP53 (inactivating) and KIT (activating) mutations. Conclusions: Patients basal mutant BRAF/NRAS could have more probability of benefit from BO-112 and pembrolizumab combination. PD-L1 and/or CD8 increase is an early marker of response. These findings could help to select patients in future clinical trials. Further investigation into predictive biomarkers is warranted. Citation Format: Ruth Roman, Philippe Saiag, Caroline Dutriaux, Luis de la Cruz Merino, Eduardo Castanon, Miguel F. Sanmamed, Caroline Robert, Juan F. Rodríguez-Moreno, Pablo Cerezuela-Fuentes, Ana M. Arance, María González Cao, Henry Montaudié, María Pilar López Criado, Julie Charles, Alfonso Berrocal, María del Carmen Álamo de la Gala, Enrique de Miguel, Elisa Funk-Brentano, Sorilla Prey, Eva Muñoz-Couselo, Delvys Rodríguez Abreu, Juan Martín-Liberal, Helena Escuin-Ordinas, Mark Branum, Sonia Macia, Marisol Quintero, Javier Sánchez López, Marya F. Chaney, Beatriz García-Peláez, Marta Vives-Usano, Miguel Ángel Molina, Stéphane Dalle, Iván Márquez-Rodas. Correlation of biomarkers and clinical benefit of intratumoral BO112 and pembrolizumab in patients with anti PD1 refractory melanoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr CT107.

P-178 Diffusion-weighted magnetic resonance imaging as an early predictive marker of chemoradiotherapy response in squamous cell carcinoma of the anus: An individual patient data meta-analysis

Patients with squamous cell carcinoma of the anus (SCCA) are at risk of locoregional recurrence after chemoradiotherapy (CRT). An early prognostic marker of treatment response would enable timely individualisation of treatment for patients with SCCA. Diffusion-weighted (DW) magnetic resonance imaging (MRI) features, such as apparent diffusion coefficient (ADC), may be prognostic; however, few trials with small patient numbers exist for SCCA. Using an individual patient data meta-analysis, we aimed to investigate in a larger cohort whether ADC based histogram parameters from paired DW-MRI at baseline and during CRT correlate with local or any relapse in patients with SCCA.

Comparative single-cell RNA-sequencing profiling of BMP4-treated primary glioma cultures reveals therapeutic markers.

Glioblastoma (GBM) is the most aggressive primary brain tumor. Its cellular composition is very heterogeneous, with cells exhibiting stem-cell characteristics (GSCs) that co-determine therapy resistance and tumor recurrence. Bone Morphogenetic Protein (BMP)-4 promotes astroglial and suppresses oligodendrocyte differentiation in GSCs, processes associated with superior patient prognosis. We characterized variability in cell viability of patient-derived GBM cultures in response to BMP4 and, based on single-cell transcriptome profiling, propose predictive positive and early-response markers for sensitivity to BMP4. Cell viability was assessed in 17 BMP4-treated patient-derived GBM cultures. In two cultures, one highly-sensitive to BMP4 (high therapeutic efficacy) and one with low-sensitivity, response to treatment with BMP4 was characterized. We applied single-cell RNA-sequencing, analyzed the relative abundance of cell clusters, searched for and identified the aforementioned two marker types, and validated these results in all 17 cultures. High variation in cell viability was observed after treatment with BMP4. In three cultures with highest sensitivity for BMP4, a substantial new cell subpopulation formed. These cells displayed decreased cell proliferation and increased apoptosis. Neuronal differentiation was reduced most in cultures with little sensitivity for BMP4. OLIG1/2 levels were found predictive for high sensitivity to BMP4. Activation of ribosomal translation (RPL27A, RPS27) was up-regulated within one day in cultures that were very sensitive to BMP4. The changes in composition of patient-derived GBM cultures obtained after treatment with BMP4 correlate with treatment efficacy. OLIG1/2 expression can predict this efficacy, and upregulation of RPL27A and RPS27 are useful early-response markers.

Dynamic Resting-State Network Biomarkers of Antidepressant Treatment Response

BackgroundDelivery of effective antidepressant treatment has been hampered by a lack of objective tools for predicting or monitoring treatment response. This study aimed to address this gap by testing novel dynamic resting-state functional network markers of antidepressant response. MethodsThe Establishing Moderators and Biosignatures of Antidepressant Response in Clinical Care (EMBARC) study randomized adults with major depressive disorder to 8 weeks of either sertraline or placebo, and depression severity was evaluated longitudinally. Participants completed resting-state neuroimaging pretreatment and again after 1 week of treatment (n = 259 eligible for analyses). Coactivation pattern analyses identified recurrent whole-brain states of spatial coactivation, and computed time spent in each state for each participant was the main dynamic measure. Multilevel modeling estimated the associations between pretreatment network dynamics and sertraline response and between early (pretreatment to 1 week) changes in network dynamics and sertraline response. ResultsDynamic network markers of early sertraline response included increased time in network states consistent with canonical default and salience networks, together with decreased time in network states characterized by coactivation of cingulate and ventral limbic or temporal regions. The effect of sertraline on depression recovery was mediated by these dynamic network changes. In contrast, early changes in dynamic functioning of corticolimbic and frontoinsular-default networks were related to patterns of symptom recovery common across treatment groups. ConclusionsDynamic resting-state markers of early antidepressant response or general recovery may assist development of clinical tools for monitoring and predicting effective intervention.

Imaging of Cancer Immunotherapy: Response Assessment Methods, Atypical Response Patterns, and Immune-Related Adverse Events, From the AJR Special Series on Imaging of Inflammation.

The introduction of immunotherapy with immune-checkpoint inhibitors (ICIs) has revolutionized cancer treatment paradigms. Since FDA approval of the first ICI in 2011, multiple additional ICIs have been approved and granted marketing authorization, and many promising agents are in early clinical adoption. Due to the distinctive biologic mechanisms of ICIs, the patterns of tumor response and progression seen with immunotherapy differ from those observed with cytotoxic chemothera-pies. With increasing clinical adoption of immunotherapy, it is critical for radiologists to recognize different response patterns and common pitfalls to avoid misinterpretation of imaging studies or prompt premature cessation of potentially effective treatment. This review provides an overview of ICIs and their mechanisms of action and discusses anatomic and metabolic immune-related response assessment methods, typical and atypical patterns of immunotherapy response (including pseudoprogression, hyperprogression, dissociated response, and durable response), and common imaging features of immune-related adverse events. Future multicenter trials are needed to validate the proposed immune-related response criteria and identify the functional imaging markers of early treatment response and survival.

18P Baseline and dynamic changes in haemoglobin levels predict treatment response and disease progression in metastatic renal cell carcinoma

Early clinical markers of response to first-line treatment with immune checkpoint inhibitors (ICI) and VEGF inhibitors (VEGFI) in metastatic renal cell carcinoma (mRCC) are lacking. We explore whether baseline and dynamic changes in haemoglobin (Hb) is associated with treatment response and disease progression.

12P Circulating tumor DNA as early marker of response to treatment in stage IV gastrointestinal cancer

Circulating tumor DNA (ctDNA) represents a promising tool for diagnosis, prognosis and treatment monitoring of several malignant diseases. We aimed to investigate ctDNA as an early marker of response to treatment.

Abstract P3-03-07: Single-institution retrospective analysis of lymph node (LN) change on breast MRI in patients with high risk early-stage breast cancer receiving neoadjuvant chemotherapy with and without immunotherapy on the ISPY-2 TRIAL

Abstract Background: The I-SPY2 TRIAL has shown that the addition of pembrolizumab to standard neoadjuvant chemotherapy results in improved rates of estimated pathologic complete response (pCR) for hormone-receptor positive (HR+) as well as triple negative breast cancer (TNBC). I-SPY2 has tested a number of novel immunotherapy combinations including the combination of pembrolizumab and SD-101, a synthetic oligonucleotide with cytidine-phospho-guanosine (CpG) motifs that stimulates plasmacytoid dendritic cells (pDC) through engagement of toll-like receptor 9 (TLR9). Biomarkers of response to immunotherapy may be different than chemotherapy, and pathologic response may not fully reflect the benefit from checkpoint inhibitors. Early markers of response to immunotherapy are needed to minimize the risk of immune-related toxicity in patients who are unlikely to benefit. The objective of this study is to assess the change in regional lymph nodes (LNs) by breast MRI in I-SPY2 patients receiving neoadjuvant chemotherapy +/- immunotherapy, and to explore if changes in regional LNs correlate with pCR and residual cancer burden (RCB). Methods: This is a retrospective study of the prospective multicenter I-SPY2 adaptive neoadjuvant trial investigating all patients enrolled at UCSF in 3 study arms between Dec 2015 and April 2021: 1) Control (weekly paclitaxel 80 mg/m2 x 12 weeks followed by AC x 4); 2) weekly paclitaxel + pembrolizumab 200 mg IV every 3 weeks, followed by AC x 4; 3) weekly paclitaxel + every 3 week pembrolizumab + intra-tumoral SD-101 weekly x 4 then every 3 weeks x 2 followed by AC x 4. Serial pre-operative breast MRIs were performed in all patients at baseline, 3 weeks, 12 weeks, and 20 weeks. A single breast radiologist blinded to treatment arm reviewed all MRIs for all patients included in this study and assessed longest diameter and cortical thickness of the largest ipsilateral axillary LN, number and location of abnormal LNs, and development of new abnormal LNs over time. Rates of pCR and RCB were evaluated in patients who showed evidence of LN growth and/or development of new lymphadenopathy (LAD) compared to those who did not. A two-sample test for equality of proportions to measure the statistical significance at alpha=.5 between control and immunotherapy arms and LN change was used. Results: A total of 43 patients were included, of whom 16 were in the control group, 11 received pembrolizumab, and 16 received pembrolizumab + SD-101. Median age was 45 years, mean tumor size was 4.8 cm, and 60% of tumors were HR+HER2-negative with the remaining 40% being TNBC. Baseline patient and tumor characteristics were similar between the 3 study arms. LN enlargement and/or development of new LAD over time was significantly more common in patients receiving immunotherapy than patients in the control arm (48.1% versus 6.3%, p=0.006). This was seen in both HR+ and TN subtypes. While there was a numerically higher rate of pCR/RCB-1 pathology in patients with increased and/or new LAD compared to those without (64% vs 51%), this difference was not statistically significant. The association of LN change and immune-related toxicities will be reported. Conclusion: The addition of immunotherapy to standard neoadjuvant chemotherapy in the I-SPY2 trial was associated with an increase in size of ipsilateral axillary LN and/or development of new LAD on serial breast MRI imaging during the course of neoadjuvant treatment. These changes were not associated with worse pathologic response at surgery and should not be assumed to be due to disease progression. Whether these changes could reflect immunotherapy benefit needs to be investigated in a larger trial with longer follow-up. Citation Format: Anika Christofferson, Elissa Price, Rita A Mukhtar, Amrita Basu, Laura Esserman, A Jo Chien. Single-institution retrospective analysis of lymph node (LN) change on breast MRI in patients with high risk early-stage breast cancer receiving neoadjuvant chemotherapy with and without immunotherapy on the ISPY-2 TRIAL [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P3-03-07.

Age and Primary Vaccination Background Influence the Plasma Cell Response to Pertussis Booster Vaccination.

Pertussis is a vaccine-preventable disease caused by the bacterium Bordetella pertussis. Over the past years, the incidence and mortality of pertussis increased significantly. A possible cause is the switch from whole-cell to acellular pertussis vaccines, although other factors may also contribute. Here, we applied high-dimensional flow cytometry to investigate changes in B cells in individuals of different ages and distinct priming backgrounds upon administration of an acellular pertussis booster vaccine. Participants were divided over four age cohorts. We compared longitudinal kinetics within each cohort and between the different cohorts. Changes in the B-cell compartment were correlated to numbers of vaccine-specific B- and plasma cells and serum Ig levels. Expansion and maturation of plasma cells 7 days postvaccination was the most prominent cellular change in all age groups and was most pronounced for more mature IgG1+ plasma cells. Plasma cell responses were stronger in individuals primed with whole-cell vaccine than in individuals primed with acellular vaccine. Moreover, IgG1+ and IgA1+ plasma cell expansion correlated with FHA-, Prn-, or PT- specific serum IgG or IgA levels. Our study indicates plasma cells as a potential early cellular marker of an immune response and contributes to understanding differences in immune responses between age groups and primary vaccination backgrounds.

Do Human iPSC-Derived Cardiomyocytes Cultured on PLA Scaffolds Induce Expression of CD28/CTLA-4 by T Lymphocytes?

Many research groups have developed various types of tissue-engineered cardiac constructs. However, the immunological properties of such artificial tissues are not yet fully understood. Previously, we developed microfiber scaffolds carrying human iPSC-derived cardiomyocytes (hiPSC-CM). In this work, we evaluated the ability of these tissue-engineered constructs to activate the expression of CD28 and CTLA-4 proteins on T lymphocytes, which are early markers of the immune response. For this purpose, electrospun PLA microfiber scaffolds were seeded with hiPSC-CM and cultured for 2 weeks. Allogeneic mononuclear cells were then co-cultured for 48 h with three groups of samples: bare scaffolds, pure cardiomyocyte culture and tissue-engineered constructs, followed by analysis of CD28/CTLA-4 expression on T lymphocytes using flow cytometry. PLA scaffolds and concanavalin A stimulation (positive control) statistically significantly increased CD28 expression on CD4+ T cells (up to 61.3% and 66.3%) CD8+ T cells (up to 17.8% and 21.7%). CD28/CTLA-4 expression was not increased when T lymphocytes were co-cultured with cardiac tissue-engineered constructs and iPSC-CM monolayers. Thus, iPSC-CM in monolayers and on PLA microfiber scaffolds did not induce T cell activation, which suggests that such cardiac constructs would not be a cause of rejection after implantation.

VEGF and IL-6 Correlation in POEMS: a Potential Upcoming Marker of Active Disease and Early Autologous BMT Response.

Introduction: VEGF function may be responsible for most POEMS manifestations, and it is considered a reliable marker of disease. COVID-19 era arose increasing interest for other inflammatory cytokines, with particular focus on Interleukin-6; VEGF production is stimulated by IL-6 and IL1β, whose concentrations appear to be elevated in clonal plasma cells. Objectives: This study aims to simultaneously evaluate VEGF and IL-6 values in patients (pts) with POEMS at different stages of the disease to find a correlation between them. Methods: We performed a monocentric study, measuring serum levels of VEGF and IL-6 in 8 POEMS pts at different time points of the disease. Results: We observed elevated serum levels of both VEGF and IL-6 in three pts before transplant, while the day after the infusion of autologous stem cells, we observed a steep decrease of both serum markers. Among the four-pts tested only after transplant, two presented with a consensual level of VEGF and IL-6, while the others did not correlate. One patient observed at POEMS diagnosis, during active disease, presented with strikingly high levels of both serum markers. Conclusions: So far, to the best of our knowledge, IL-6 could be considered as a marker of active disease and reliable up to the very first months after BMT, after which its accuracy appears to be lost due to unknown factors, still to be investigated.

Early Response to Chemotherapy in Malignant Pleural Mesothelioma Evaluated Using Diffusion-Weighted Magnetic Resonance Imaging: Initial Observations

IntroductionWe compared the magnetic resonance imaging total tumor volume (TTV) and median apparent diffusion coefficient (ADC) of malignant pleural mesothelioma (MPM) before and at 4 weeks after chemotherapy, to evaluate whether these are potential early markers of treatment response. MethodsDiffusion-weighted magnetic resonance imaging was performed in 23 patients with MPM before and after 4 weeks of chemotherapy. The TTV was measured by semiautomatic segmentation (GrowCut) and transferred onto ADC maps to record the median ADC. Test-retest repeatability of TTV and ADC was evaluated in eight patients. TTV and median ADC changes were compared between responders and nonresponders, defined using modified Response Evaluation Criteria In Solid Tumors on computed tomography (CT) at 12 weeks after treatment. TTV and median ADC were also correlated with CT size measurement and disease survival. ResultsThe test-retest 95% limits of agreement for TTV were −13.9% to 16.2% and for median ADC −1.2% to 3.3%. A significant increase in median ADC in responders was observed at 4 weeks after treatment (p = 0.02). Correlation was found between CT tumor size change at 12 weeks and median ADC changes at 4 weeks post-treatment (r = −0.560, p = 0.006). An increase in median ADC greater than 5.1% at 4 weeks has 100% sensitivity and 90% specificity for responders (area under the curve = 0.933, p < 0.001). There was also moderate correlation between median tumor ADC at baseline and overall survival (r = 0.45, p = 0.03). ConclusionsDiffusion-weighted magnetic resonance imaging measurements of TTV and median ADC in MPM have good measurement repeatability. Increase in ADC at 4 weeks post-treatment has the potential to be an early response biomarker.