Organoids for Functional Precision Medicine in Advanced Pancreatic Cancer.

BACKGROUND & AIMS: Patient-derived organoids (PDOs) are promising tumor avatars that could enable ex vivo drug tests to personalize patients' treatments in the frame of functional precision oncology. However, clinical evidence remains scarce. This study aims to evaluate whether PDOs can be implemented in clinical practice to benefit patients with advanced refractory pancreatic ductal adenocarcinoma (PDAC). METHODS: During 2021 to 2022, 87 patients were prospectively enrolled in an institutional review board-approved protocol. Inclusion criteria were histologically confirmed PDAC with the tumor site accessible. A panel of 25 approved antitumor therapies (chemogram) was tested and compared to patient responses to assess PDO predictive values and map the drug sensitivity landscape in PDAC. RESULTS: Fifty-four PDOs were generated from 87 pretreated patients (take-on rate, 62%). The main PDO mutations were KRAS (96%), TP53 (88%), and CDKN2A/B (22%), with a 91% concordance rate with their tumor of origin. The mean turnaround time to chemogram was 6.8 weeks. In 91% of cases, ≥1 hit was identified (gemcitabine (n = 20 of 54), docetaxel (n = 18 of 54), and vinorelbine (n = 17 of 54), with a median of 3 hits/patient (range, 0-12). Our cohort included 34 evaluable patients with full clinical follow-up. We report a chemogram sensitivity of 83.3% and specificity of 92.9%. The overall response rate and progression-free survival were higher when patients received a hit treatment as compared to patients who received a nonhit drug (as part of routine management). Finally, we leveraged our PDO collection as a platform for drug validation and combo identification. We tested anti-KRASG12D (MRTX1133), alone or combined, and identified a specific synergy with anti-EGFR therapies in KRASG12D variants. CONCLUSIONS: We report the largest prospective study aiming at implementing PDO-based functional precision oncology and identify very robust predictive values in this clinical setting. In a clinically relevant turnaround time, we identify putative hits for 91% of patients, providing unexpected potential survival benefits in this very aggressive indication. Although this remains to be confirmed in interventional precision oncology trials, PDO collection already provides powerful opportunities for drugs and combinatorial treatment development.

Clinical and molecular features of early onset pancreatic adenocarcinoma.

Pancreatic adenocarcinoma (PDAC) is a major health burden and may become the second cause of death by cancer in developed countries. The incidence of early-onset pancreatic cancer (EOPC, defined by an age at diagnosis <50 years old) is increasing. Here, we conducted a study of all PDAC patients followed at our institution. Patients were classified as EOPC or non-early onset (nEOPC, >50). Eight hundred and seventy eight patients were included, of which 113 EOPC, exhibiting a comparable performance status. EOPC were more often diagnosed at the metastatic stage (70.0% vs 58.3%) and liver metastases were more prevalent at diagnosis (60.2% vs. 43.9%). The median overall survival (OS) from diagnosis was 18.1 months, similar between EOPC and nEOPC. Among patients who underwent surgery, recurrence-free survival was similar between age groups. Among metastatic patients, first line progression free survival was similar but EOPC received more treatment lines (72.3% vs. 58.1% received ≥2 lines). Regarding molecular alterations, the mean tumor mutational burden (TMB) was lower in EOPC (1.42 vs. 2.95 mut/Mb). The prevalence of KRAS and BRCA1/2 mutations was similar, but EOPC displayed fewer alterations in CNKN2A/B. Fifty eight patients (18.6%) had actionable alterations (ESCAT I-III) and 31 of them received molecularly matched treatments. On the transcriptomic level, despite its clinical aggressiveness, EOPC was less likely to display a basal-like phenotype. To conclude, EOPC were diagnosed more frequently at the metastatic stage. OS and 1st line PFS were similar to nEOPC. EOPC displayed specific molecular features, such as a lower TMB and fewer alterations in CDKN2A/B.

Management of biliary tract cancers in early-onset patients: A nested multicenter retrospective study of the ACABI GERCOR PRONOBIL cohort.

BACKGROUND & AIMS: Accumulating data has shown the rising incidence and poor prognosis of early-onset gastrointestinal cancers, but few data exist on biliary tract cancers (BTC). We aimed to analyse the clinico-pathological, molecular, therapeutic characteristics and prognosis of patients with early onset BTC (EOBTC, age ≤50 years at diagnosis), versus olders. METHODS: We analysed patients diagnosed with intrahepatic cholangiocarcinoma, extrahepatic cholangiocarcinoma, and gallbladder adenocarcinoma between 1 January 2003 and 30 June 2021. Baseline characteristics and treatment were described in each group and compared. Progression-free survival, overall survival and disease-free survival were estimated in each group using the Kaplan-Meier method. RESULTS: Overall, 1256 patients were included, 188 (15%) with EOBTC. Patients with EOBTC demonstrated fewer comorbidities (63.5% vs. 84.5%, p < .0001), higher tumour stage (cT3-4: 50.0% vs. 32.3%, p = .0162), bilobar liver involvement (47.8% vs. 32.1%, p = .0002), and metastatic disease (67.6% vs. 57.5%, p = .0097) compared to older. Patients with EOBTC received second-line therapy more frequently (89.5% vs. 81.0% non-EOBTC, p = .0224). For unresectable patients with BTC, median overall survival was 17.0 vs. 16.2 months (p = .0876), and median progression-free survival was 5.8 vs. 6.0 months (p = .8293), in EOBTC vs. older. In advanced stages, fewer actionable alterations were found in EOBTC (e.g., IDH1 mutations [7.8% vs. 16.6%]; FGFR2-fusion [11.7% vs. 8.9%]; p = .029). CONCLUSIONS: Patients with EOBTC have a more advanced disease at diagnosis, are treated more heavily at an advanced stage but show similar survival. A distinctive molecular profile enriched for FGRF2 fusions was found.

Exploring the Role of Target Expression in Treatment Efficacy of Antibody-Drug Conjugates (ADCs) in Solid Cancers: A Comprehensive Review.

PURPOSE OF REVIEW: Antibody-drug conjugates (ADCs) offer a promising path for cancer therapy, leveraging the specificity of monoclonal antibodies and the cytotoxicity of linked drugs. The success of ADCs hinges on precise targeting of cancer cells based on protein expression levels. This review explores the relationship between target protein expression and ADC efficacy in solid tumours, focusing on results of clinical trials conducted between January 2019 and May 2023. RECENT FINDINGS: We hereby highlight approved ADCs, revealing their effectiveness even in low-expressing target populations. Assessing target expression poses challenges, owing to variations in scoring systems and biopsy types. Emerging methods, like digital image analysis, aim to standardize assessment. The complexity of ADC pharmacokinetics, tumour dynamics, and off-target effects emphasises the need for a balanced approach. This review underscores the importance of understanding target protein dynamics and promoting standardized evaluation methods in shaping the future of ADC-based cancer therapies.

Case report: Microsatellite instability determination is not always black and white in Lynch syndrome diagnosis.

Introduction: Microsatellite instability (MSI) is a genetic marker that is useful in the detection and treatment of Lynch syndrome (Sd). Although conventional techniques such as immunohistochemistry (IHC) and polymerase chain reaction (PCR) are the standards for MSI detection, the advent of next-generation sequencing (NGS) has offered new possibilities, especially with circulating DNA. Case report: We present the case of a 26-year-old patient with Lynch Sd and a BRAF-mutated metastatic colon cancer. The discordant MSI results between the conventional methods and NGS posed challenges in making treatment decisions. Subsequent NGS analysis revealed a high MSI status, leading to participation in an immunotherapy trial, with remarkable clinical response. Conclusion: This case emphasizes the importance of comprehensive molecular profiling and strong interdisciplinary collaborations, especially in cases with ambiguous MSI results.

Role of molecular biology in the management of pancreatic cancer.

Pancreatic ductal adenocarcinoma (PDAC) presents significant challenges in patient management due to a dismal prognosis, increasing incidence, and limited treatment options. In this regard, precision medicine, which personalizes treatments based on tumour molecular characteristics, has gained great interest. However, its widespread implementation is not fully endorsed in current recommendations. This review explores key molecular alterations in PDAC, while emphasizing differences between KRAS-mutated and KRAS-wild-type tumours. It assesses the practical application of precision medicine in clinical settings and outlines potential future directions with respect to PDAC. Actionable molecular targets are examined with the aim of enhancing our understanding of PDAC molecular biology. Insights from this analysis may contribute to a more refined and personalized approach to pancreatic cancer treatment, ultimately improving patient outcomes.

Molecular profiling of biliary tract cancers reveals distinct genomic landscapes between circulating and tissue tumor DNA.

Biliary tract cancers (BTCs) are heterogeneous malignancies with dismal prognosis due to tumor aggressiveness and poor response to limited current therapeutic options. Tumor exome profiling has allowed to successfully establish targeted therapeutic strategies in the clinical management of cholangiocarcinoma (CCA). Still, whether liquid biopsy profiling could inform on BTC biology and patient management is unknown. In order to test this and generate novel insight into BTC biology, we analyzed the molecular landscape of 128 CCA patients, using a 394-gene NGS panel (Foundation Medicine). Among them, 32 patients had matched circulating tumor (ct) DNA and tumor DNA samples, where both samples were profiled. In both tumor and liquid biopsies, we identified an increased frequency of alterations in genes involved in genome integrity or chromatin remodeling, including ARID1A (15%), PBRM1 (9%), and BAP1 (14%), which were validated using an in-house-developed immunohistochemistry panel. ctDNA and tumor DNA showed variable concordance, with a significant correlation in the total number of detected variants, but some heterogeneity in the detection of actionable mutations. FGFR2 mutations were more frequently identified in liquid biopsies, whereas KRAS alterations were mostly found in tumors. All IDH1 mutations detected in tumor DNA were also identified in liquid biopsies. These findings provide novel insights in the concordance between the tumor and liquid biopsies genomic landscape in a large cohort of patients with BTC and highlight the complementarity of both analyses when guiding therapeutic prescription.

Precision medicine for KRAS wild-type pancreatic adenocarcinomas.

BACKGROUND: KRAS mutation is the most common molecular alteration in pancreatic adenocarcinoma (PDAC), and around 10% of patients harbor KRAS wild-type tumors (KRASWT). METHODS: A retrospective chart review of clinical/molecular data was performed including all PDAC patients with a determined KRAS status (tumor molecular profiling on tissue or liquid biopsy). RESULTS: 342 patients were included with 54 KRASWT PDAC (16%) compared to 288 patients with KRASm PDAC. Median age was 61 years [IQR:54.0;67.0] and 164 pts (48%) were female. At diagnosis, KRASWT patients (63%) were more frequently diagnosed at a non-metastatic stage compared to KRASm patients (41%) (p = 0.003). Regarding metastatic sites, liver was less frequent in KRASWT (39%, p < 0.0001). Median overall survival (mOS) from initial diagnosis was significantly higher in the KRASWT group compared to KRASm (50.8 months, CI95% [32.0-NR] vs 21.1 months, CI95% [18.9-23.4] (p < 0.004 after adjustment on age, ECOG and stage at diagnosis). In first-line systemic treatment, (mostly FOLFIRINOX) progression-free survival (PFS) was also higher in KRASWT. Based on ESCAT classification, a putative actionable alteration (ESCAT I-III) was identified in 19 (36%) KRASWT pts and 46 (16%) KRASm patients (p < 0.0001) with more alterations in FGFR2, BRAF(V600E), NRTK and more MSI tumors. KRASWT harbored also fewer alterations in TP53, CDKN2A, and SMAD4. 12 KRASWT patients received a molecularly-matched treatment with clinical benefit and improved outcomes compared to KRASm patients. CONCLUSIONS: KRASWT patients display distinct disease characteristics and outcomes with prolonged overall survival. KRASWT patients also harbor more actionable molecular alterations, leading to higher survival rates after receiving molecularly matched treatments.

Genomic landscape of liquid biopsy mutations in TP53 and DNA damage genes in cancer patients.

Next-generation sequencing (NGS) assays based on plasma cell-free DNA (cfDNA) are increasingly used for clinical trials inclusion. Their optimized limit of detection applied to a large number of genes leads to the identification of mutations not confirmed in tissue. It becomes essential to describe the characteristics and consequences of these liquid biopsy-only mutations. In the STING protocol (Gustave Roussy, NCT04932525), 542 patients with advanced solid cancer had cfDNA-based and tissue-based NGS analysis (performed by FoundationOne® Liquid CDx and FoundationOne CDx™, respectively). Mutations identified in the liquid biopsy but not in the paired tissue were considered as liquid biopsy-only mutations irrespective of their variant allelic frequency (VAF). Out of 542 patients, 281 (51.8%) harbored at least one liquid biopsy-only mutation. These patients were significantly older, and more heavily pretreated. Liquid biopsy-only mutations occurring in TP53, and in DDR genes (ATM, CHEK2, ATR, BRCA2, and BRCA1) accounted for 90.8% of all the mutations. The median VAF of these mutations was generally low (0.37% and 0.40% for TP53 and DDR genes respectively). The variant type repartition depended on the gene. Liquid biopsy-only mutations affected hotspot in TP53 codon 273, 125, 195, 176, 237 or 280 and ATM codon 2891 and 3008. In a subset of 37 patients, 75.0%, 53.5% and 83.3% of the liquid biopsy-only mutations occurring respectively in ATM, TP53, and CHEK2 were confirmed in the matching whole blood sample. Although liquid biopsy-only mutations makes the interpretation of liquid biopsy results more complex, they have distinct characteristics making them more easily identifiable.