Safety and preliminary efficacy of pembrolizumab following trans-arterial chemoembolization for hepatocellular carcinoma: the PETAL phase Ib study

BACKGROUND

TACE may prime adaptive immunity and enhance immunotherapy efficacy. PETAL evaluated safety, preliminary activity of TACE plus pembrolizumab and explored mechanisms of efficacy.

METHODS

Patients with liver-confined HCC were planned to receive up to 2 rounds of TACE followed by pembrolizumab 200 mg every 21 days commencing 30-days post-TACE until disease progression or unacceptable toxicity for up to 1 year. Primary endpoint was safety, 21-days dose-limiting toxicities (DLT) from pembrolizumab initiation. Secondary endpoints included progression-free survival (PFS) and evaluation of tumour and host determinants of response.

RESULTS

Fifteen patients were included in the safety and efficacy population: 73% had non-viral cirrhosis, median age was 72 years. Child-Pugh (CP) class was A in 14 patients. Median tumour size was 4 cm. Ten patients (67%) received pembrolizumab after 1 TACE, 5 patients after 2 (33%). Pembrolizumab yielded no synergistic toxicity nor DLTs post-TACE. Treatment-related adverse events occurred in 93% of patients most commonly skin rash (40%), fatigue and diarrhoea (27%). After a median follow-up of 38.5 months, objective response rate (ORR) 12 weeks post-TACE was 53%. PFS rate at 12 weeks was 93% and median PFS was 8.95 months (95%CI 7.30-NA). Median duration of response was 7.3 months (95%CI: 6.3-8.3). Median OS was 33.5 months (95%CI: 11.6-NA). Dynamic changes in peripheral T-cell subsets, circulating tumour DNA, serum metabolites and in stool bacterial profiles highlight potential mechanisms of action of multi-modal therapy.

CONCLUSIONS

TACE plus pembrolizumab was tolerable with no evidence of synergistic toxicity, encouraging further clinical development of immunotherapy alongside TACE.

Efficacy and safety of frontline systemic therapy for advanced HCC: A network meta-analysis of landmark phase III trials

Background & Aims

Direct comparisons across first-line regimens for advanced hepatocellular carcinoma are not available. We performed a network metanalysis of phase III of trials to compare first-line systemic treatments for hepatocellular carcinoma in terms of overall survival (OS), progression-free survival (PFS), objective response rate, disease control rate, and incidence of adverse events (AEs).

Methods

After performing a literature review from January 2008 to September 2022, we screened 6,329 studies and reviewed 3,009 studies, leading to identification of 15 phase III trials for analysis. We extracted odds ratios for objective response rate and disease control rate, relative risks for AEs, and hazard ratios (HRs) with 95% CIs for OS and PFS, and used a frequentist network metanalysis, with fixed-effect multivariable meta-regression models to estimate the indirect pooled HRs, odds ratios, relative risks, and corresponding 95% CIs, considering sorafenib as reference.

Results

Of 10,820 included patients, 10,444 received active treatment and 376 placebo. Sintilimab + IBI350, camrelizumab + rivoceranib, and atezolizumab + bevacizumab provided the greatest reduction in the risk of death compared with sorafenib, with HRs of 0.57 (95% CI 0.43-0.75), 0.62 (95% CI 0.49-0.79), and 0.66 (95% CI 0.52-0.84), respectively. Considering PFS, camrelizumab + rivoceranib and pembrolizumab + lenvatinib were associated with the greatest reduction in the risk of PFS events compared with sorafenib, with HRs of 0.52 (95% CI 0.41-0.65) and 0.52 (95% CI 0.35-0.77), respectively. Immune checkpoint inhibitor (ICI) monotherapies carried the lowest risk for all-grade and grade ≥3 AEs.

Conclusions

The combinations of ICI + anti-vascular endothelial growth factor, and double ICIs lead to the greatest OS benefit compared with sorafenib, whereas ICI + kinase inhibitor regimens are associated with greater PFS benefit at the cost of higher toxicity rates.

Impact and Implications

In the last few years, many different therapies have been studied for patients with primary liver cancer that cannot be treated with surgery. In these cases, anticancer drugs (alone or in combination) are given with the intent to keep the cancer at bay and, ultimately, to prolong survival. Among all the therapies that have been investigated, the combination of immunotherapy (drugs that boost the immune system against the cancer) and anti-angiogenic agents (drugs that act on tumoural vessels) has appeared the best to improve survival. Similarly, the combination of two types of immunotherapies that activate the immune system at different levels has also shown positive results.

Systematic Review Registration

PROSPERO CRD42022366330.

Taxonomic reclassification of Kaposi Sarcoma identifies disease entities with distinct immunopathogenesis

BACKGROUND

The taxonomy of Kaposi Sarcoma (KS) is based on a classification system focused on the description of clinicopathological features of KS in geographically and clinically diverse populations. The classification includes classic, endemic, epidemic/HIV associated and iatrogenic KS, and KS in men who have sex with men (MSM). We assessed the medical relevance of the current classification of KS and sought clinically useful improvements in KS taxonomy.

METHODS

We reviewed the demographic and clinicopathological features of 676 patients with KS, who were referred to the national centre for HIV oncology at Chelsea Westminster hospital between 2000 and 2021.

RESULTS

Demographic differences between the different subtypes of KS exist as tautological findings of the current classification system. However, no definitive differences in clinicopathological, virological or immunological parameters at presentation could be demonstrated between the classic, endemic or MSM KS patients. Reclassifying patients as either immunosuppressed or non-immunosuppressed, showed that the immunosuppressed group had a significantly higher proportion of adverse disease features at presentation including visceral disease and extensive oral involvement, classified together as advanced disease (chi² P = 0.0012*) and disseminated skin involvement (chi² P < 0.0001*). Immunosuppressed patients had lower CD4 counts, higher CD8 counts and a trend towards higher HHV8 levels compared to non-immunosuppressed patients, however overall survival and disease specific (KS) survival was similar across groups.

CONCLUSION

The current system of KS classification does not reflect meaningful differences in clinicopathological presentation or disease pathogenesis. Reclassification of patients based on the presence or absence of immunosuppression is a more clinically meaningful system that may influence therapeutic approaches to KS.

Mainstreaming of genomics in oncology: a nationwide survey of the genomics training needs of UK oncologists

OBJECTIVE

Genomics is rapidly changing treatment paradigms for cancers, obligating oncologists to have good genomics knowledge. Through this survey, we aimed to assess the current understanding of cancer genomics among UK oncologists.

METHODS

We conducted a web-based nation-wide self-assessment survey of the cancer genomics knowledge of UK clinical and medical oncology trainees and consultants.

RESULTS

In total, 150 oncologists (81 consultants and 69 trainees) responded, representing 10% of UK oncologists.Formal training in genomics had not been received by 38.7% of oncologists and 92.7% identified a need for additional genomics training.In total, 71.3% self-reported to have good knowledge of defining somatic and germline mutations, falling to 35.3% for understanding principles of gene expression and regulation. Knowledge of cancer-predisposing syndromes was highest for Lynch syndrome (40.7% good knowledge) and lowest for multiple endocrine neoplasia (14.0% good knowledge).Overall, 49.0% of respondents had consented patients for germline testing, but 80.7% reported a lack of training in genetic counselling.

CONCLUSION

Large knowledge gaps have been identified through this survey, highlighting the need for incorporation of improved formal training in cancer genomics for consultants and trainees, with an aim to equip oncologists for advances in clinical practice and to take up genetic mainstreaming confidently.

New Frontiers in the Medical Therapy of Hepatocellular Carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) is the most common primary liver tumor, and it rates fourth as a cause of cancer-related death. The presence of underlying liver disease and poor chemosensitivity pose major treatment challenges in the management of HCC. However, in the last few years, the therapeutic scenario has substantially changed, and immunotherapy in the form of immune checkpoint inhibitors (ICPIs) has become an essential therapeutic strategy in this field.

SUMMARY

After controversial results of monotherapy, ICPIs have been mainly investigated in association with antiangiogenic agents or as dual checkpoint inhibition. The combination of atezolizumab plus bevacizumab has become the new therapeutic standard for unresectable HCC. Currently, a number of ICPI-based combinations are being studied in phase III clinical trials as front-line therapy for advanced HCC, with growing interest in integration of early-stage disease management in the form of adjuvant or neoadjuvant therapies. With most of the trials investigating ICPIs as first-line treatment, the second-line scenario relies mainly on tyrosine kinase inhibitors, which however have not been formally trialed after ICPIs.

KEY MESSAGES

In this review, we summarize the main therapeutic advances in the systemic management of HCC focusing on the most relevant ongoing trials. We also discuss the main issues arising from a such rapidly evolving field including therapeutic sequencing and patient stratification.

Circulating Tumor DNA Profiling From Breast Cancer Screening Through to Metastatic Disease

PURPOSE

We investigated the utility of the Oncomine Breast cfDNA Assay for detecting circulating tumor DNA (ctDNA) in women from a breast screening population, including healthy women with no abnormality detected by mammogram, and women on follow-up through to advanced breast cancer.

MATERIALS AND METHODS

Blood samples were taken from 373 women (127 healthy controls recruited through breast screening, 28 ductal carcinoma in situ, 60 primary breast cancers, 47 primary breast cancer on follow-up, and 111 metastatic breast cancers [MBC]) to recover plasma and germline DNA for analysis with the Oncomine Breast cfDNA Assay on the Ion S5 platform.

RESULTS

One hundred sixteen of 373 plasma samples had one or more somatic variants detected across eight of the 10 genes and were called ctDNA-positive; MBC had the highest proportion of ctDNA-positive samples (61; 55%) and healthy controls the lowest (20; 15.7%). ESR1, TP53, and PIK3CA mutations account for 93% of all variants detected and predict poor overall survival in MBC (hazard ratio = 3.461; 95% CI, 1.866 to 6.42; P = .001). Patients with MBC had higher plasma cell-free DNA levels, higher variant allele frequencies, and more polyclonal variants, notably in ESR1 than in all other groups. Only 15 individuals had evidence of potential clonal hematopoiesis of indeterminate potential mutations.

CONCLUSION

We were able detect ctDNA across the breast cancer spectrum, notably in MBC where variants in ESR1, TP53, and PIK3CA predicted poor overall survival. The assay could be used to monitor emergence of resistance mutations such as in ESR1 that herald resistance to aromatase inhibitors to tailor adjuvant therapies. However, we suggest caution is needed when interpreting results from a single plasma sample as variants were also detected in a small proportion of HCs.

Non-invasive Technology Advances in Cancer-A Review of the Advances in the Liquid Biopsy for Endometrial and Ovarian Cancers

Improving cancer survival rates globally requires improvements in disease detection and monitoring, with the aim of improving early diagnosis and prediction of disease relapse. Traditional means of detecting and monitoring cancers rely largely on imaging and, where possible, blood-based protein biomarkers, many of which are non-specific. Treatments are being improved by identification of inherited and acquired genomic aberrations in tumors, some of which can be targeted by newly developed therapeutic interventions. Treatment of gynecological malignancy is progressively moving toward personalized therapy, as exemplified by application of PARP-inhibition for patients with BRCA-deficient tubo-ovarian cancers, or checkpoint inhibition in patients with mismatch repair-deficient disease. However, the more recent discovery of a group of biomarkers described under the umbrella term of “liquid biopsy” promises significant improvement in our ability to detect and monitor cancers. The term “liquid biopsy” is used to describe an array of tumor-derived material found in blood plasma and other bodily fluids such as ascites, pleural fluid, saliva, and urine. It includes circulating tumors cells (CTCs), circulating nucleic acids including DNA, messenger RNA and micro RNAs, and extracellular vesicles (EVs). In this review, we discuss recent advancements in liquid biopsy for biomarker detection to help in diagnosis, prognosis, and planning of treatment of ovarian and endometrial cancer.

Back from the Brink: EGFR Inhibition in Gastroesophageal Cancer

Gastroesophageal adenocarcinomas (GEA) remain difficult to treat with limited targeted therapeutics. Negative results from randomized trials of EGFR inhibitors (EGFRi) in patients with molecularly unselected GEA have hampered the development of EGFRi in the gastroesophageal cancer space. A recent study reopens the game.See related article by Corso et al., p. 3126.

Longitudinal monitoring of circulating tumour DNA improves prognostication and relapse detection in gastroesophageal adenocarcinoma

BACKGROUND

Gastroesophageal adenocarcinoma (GOA) has poor clinical outcomes and lacks reliable blood markers. Here we present circulating tumour DNA (ctDNA) as an emerging biomarker.

METHODS

Forty patients (17 palliative and 23 curative) were followed by serial plasma monitoring. Primary tumour DNA was analysed by targeted next-generation sequencing to identify somatic single-nucleotide variants (SNVs), and Nanostring nCounter® to detect copy number alterations (CNAs). Patient-specific SNVs and CNA amplifications (CNAamp) were analysed in plasma using digital droplet PCR and quantitative PCR, respectively.

RESULTS

Thirty-five patients (13 palliative, 22 curative) had ≥1 SNVs and/or CNAamp detected in primary tumour DNA suitable for tracking in plasma. Eighteen of 35 patients (nine palliative, nine curative) had ≥1 ctDNA-positive plasma sample. Detection of postoperative ctDNA predicted short RFS (190 vs 934 days, HR = 3.7, p = 0.028) and subsequent relapse (PPV for relapse 0.83). High ctDNA levels (>60.5 copies/ml) at diagnosis of metastatic disease predicted poor OS (90 vs 372 days, HR = 11.7 p < 0.001).

CONCLUSION

Sensitive ctDNA detection allows disease monitoring and prediction of short OS in metastatic patients. Presence of ctDNA postoperatively predicts relapse and defines a 'molecular relapse' before overt clinical disease. This lead time defines a potential therapeutic window for additional anticancer therapy.

The Use of Transdermal Estrogen in Castrate-resistant, Steroid-refractory Prostate Cancer

BACKGROUND

Androgen-deprivation therapy is the mainstay of treatment for metastatic prostate cancer. Corticosteroids and estrogens are also useful agents in castration-resistant prostate cancer (CRPC). However, oral estrogens are associated with thromboembolic events, which limits their use, and transdermal estrogens may offer a safer alternative. This study was carried out to determine the safety and effectiveness of transdermal estrogens in CRPC.

PATIENTS AND METHODS

Forty-one patients with CRPC and steroid-resistant prostate cancer were eligible for this dose-escalation study of transdermal estradiol. A starting dose of 50 mcg/24 hours was applied and increased if prostate-specific antigen (PSA) rose > 5 ng/mL in steps to 300 mcg/24 hours. The primary endpoint was PSA response, and secondary outcomes included incidence of thromboembolic events and progression-free survival. Patients who progressed were offered diethylstilbestrol.

RESULTS

Five (13%) of 40 patients had > 50% PSA reduction for at least 1 month at any transdermal estradiol dose. No venous-thromboembolic events were observed, and responses plateaued at 200 mcg/24 hours. A correlation between PSA response and rising sex hormone binding globulin was seen. Fifty percent of patients subsequently responded to low-dose diethylstilbestrol.

CONCLUSION

Transdermal estradiol appears to be a low toxicity treatment option to control CRPC after failure of steroid therapy. Modulation of sex hormone binding globulin by transdermal estradiol may be one mechanism of action of estrogens on CRPC. Oral estrogens remain effective after the use of transdermal estradiol.

Abstract 2281: The role of baseline and early dynamics of ctDNA in predicting response and prognosis of early and advanced gastroesophageal adenocarcinomas

Background: Circulating tumor DNA (ctDNA) is emerging as a valuable less-invasive adjunct to tissue biopsy for real time monitoring and personalization of cancer treatment. This study aimed to determine the prognostic value of baseline ctDNA in both early and advanced gastroesophageal adenocarcinoma (GEA) and establish whether dynamic changes in ctDNA provides useful response and prognosis information. Patients and Methods: Formalin-fixed, paraffin-embedded (FFPE) tissue DNA and serial plasma cell-free DNA (cfDNA) were obtained from 36 patients (23 early stage (63.9%), 13 advanced stage (36.1%)) undergoing treatment for GEA. Tumor DNA was analyzed by targeted next generation sequencing (NGS) (custom ampliseq six gene panel) and Nanostring™ nCounter® technology (87 gene panel). In each patient, selected mutations and gene amplifications were profiled in serial cfDNA samples using a combination of NGS, droplet digital PCR and real-time quantitative PCR. Results: Mutations and/or gene amplifications were identified in tumor DNA of 33/36 patients (91.7%). Patient specific profiling detected ctDNA in 19/33 patients (57.6%) at baseline: 9/22 with early stage disease (40.9%) and 10/11 with advanced stage disease (90.9%). Objective Response Rate (ORR) by RECIST 1.1 criteria was 71.4% (10/14) for patients who were ctDNA negative at baseline (group A) and 52.9% (9/17) for patients with detectable ctDNA at baseline (group B). Multivariate Cox regression analysis, adjusted for stage of disease and patient performance status, showed presence of ctDNA at baseline was associated with both reduced progression free survival (PFS) and overall survival (OS) [hazard ratio (HR) of 6.2 (95% CI 1.9-19.8, P = 0.002) and 7.3 (CI 1.9-28.2, P = 0.004), respectively]. The median PFS was 34.7 months and 12.1 months and median OS was not reached and 14.5 months for group A and B, respectively (Mantel-Cox Log Rank P = 0.008 and P &lt; 0.001, respectively). ctDNA was detected before relapse in 3/22 (13.6%) early stage patients and before progression in 5/11 (45.5%) advanced stage patients, with an overall median lead-time of 6.3 weeks before radiological evidence of relapse or progression. Conclusion: This pilot study suggests that presence of ctDNA at baseline and recurrence during treatment are poor prognostic biomarkers both in early and advanced GEA.

Citation Format: Ali Abdulnabi Mohamed, Mark R. Openshaw, Barbara Ottolini, David Guttery, Daniel Fernandez Garcia, Cathy J. Richards, Jacqui A. Shaw, Anne L. Thomas. The role of baseline and early dynamics of ctDNA in predicting response and prognosis of early and advanced gastroesophageal adenocarcinomas [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 2281.

The next steps in improving the outcomes of advanced ovarian cancer

Worldwide ovarian cancer affects over 200,000 women per year. Overall survival rates are poor due to two predominate reasons. First, the majority of patients present with advanced disease creating significant difficulty with effecting disease eradication. Second, acquisition of chemotherapy resistance results in untreatable progressive disease. Advances in treatment of advanced ovarian cancer involve a spectrum of interventions including improvements in frontline debulking surgery and combination chemotherapy. Anti-angiogenic factors have been shown to have activity in frontline and recurrent disease while novel chemotherapeutic agents and targeted treatments are in development particularly for disease that is resistant to platinum-based chemotherapy. These developments aim to improve the progression-free and overall survival of women with advanced ovarian cancer.

Circulating Cell Free DNA in the Diagnosis of Trophoblastic Tumors

Gestational trophoblastic neoplasia (GTN) represents a group of diseases characterized by production of human chorionic gonadotropin (hCG). Since non-gestational tumors may occasionally secrete hCG, histopathological diagnosis is important for appropriate clinical management. However, a histopathological diagnosis is not always available. We therefore investigated the feasibility of extracting cell free DNA (cfDNA) from the plasma of women with GTN for use as a “liquid biopsy” in patients without histopathological diagnosis. cfDNA was prepared from the plasma of 20 women with a diagnosis of GTN and five with hCG-secreting tumors of unknown origin. Genotyping of cfDNA from the patient, genomic DNA from her and her partner and DNA from the tumor tissue identified circulating tumor DNA (ctDNA) (from 9% to 53% of total cfDNA) in 12 of 20 patients with GTN. In one case without a tissue diagnosis, ctDNA enabled a diagnosis of GTN originating in a non-molar conception and in another a diagnosis of non-gestational tumor, based on the high degree of allelic instability and loss of heterozygosity in the ctDNA. In summary ctDNA can be detected in the plasma of women with GTN and can facilitate the diagnosis of both gestational and non-gestational trophoblastic tumors in cases without histopathological diagnosis.

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Circulating tumor DNA can be detected in the plasma of patients with gestational trophoblastic neoplasia.

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Analysis of circulating tumor DNA may provide a diagnosis in patients with hCG-secreting tumors and no tissue biopsy.

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ctDNA may provide a source of tumor DNA for further investigation of gestational trophoblastic neoplasia.

Gestational trophoblastic neoplasia describes a group of pregnancy related cancers. These cancers produce the pregnancy hormone human chorionic gonadotropin (hCG) which is useful in diagnosing and monitoring the disease. Some non-pregnancy related cancers may also make hCG causing difficulty with diagnosis in patients without a biopsy for pathological diagnosis.

In this study we detected DNA from the cancer in patients' blood. Analysis of this DNA enabled us to distinguish cancers that were pregnancy related from those that were not. In the future we may use this technology to help diagnose pregnancy related cancers in patients where a biopsy is unavailable.

The sfr6 mutant of Arabidopsis is defective in transcriptional activation via CBF/DREB1 and DREB2 and shows sensitivity to osmotic stress

The sfr6 mutant of Arabidopsis displays a deficit in freezing tolerance after cold acclimation. We previously observed that the transcripts of three cold-, ABA- and drought-inducible genes, each having a C-repeat motif or the drought-responsive element (CRT/DRE) in its promoter, failed to normally accumulate in this mutant. We now report that the effects of sfr6 upon transcript levels are reflected in the levels of the encoded proteins, confirming that the cold-inducible protein expression is affected by the sfr6 mutation. Using microarray analysis, we found not only that this effect may be general to cold-inducible genes with CRT/DRE promoter elements, but also that it extends to some other genes whose promoters lack a CRT/DRE element. The role of the CRT/DRE has been empirically tested by use of a synthetic promoter, confirming that the CRT/DRE is sufficient to confer the sfr6 effect upon expression. Tolerance of osmotic stress was also found to be reduced in sfr6, consistent with a role in osmotic stress tolerance for the cold-, ABA- and drought-inducible genes whose expression is affected by the sfr6 mutation.