Association of personalized and tumor-informed ctDNA with patient survival outcomes in pancreatic adenocarcinoma.

INTRODUCTION: Personalized and tumor-informed circulating tumor DNA (ctDNA) testing is feasible and allows for molecular residual disease (MRD) identification in patients with pancreatic ductal adenocarcinoma (PDAC). METHODS: In this retrospective analysis of commercial cases from multiple US institutions, personalized, tumor-informed, whole-exome sequenced, and germline-controlled ctDNA levels were quantified and analyzed in patients with PDAC. Plasma samples (n = 1329) from 299 clinically validated patients were collected at diagnosis, perioperatively (MRD-window; within 2-12 weeks after surgery, before therapy), and during surveillance (>12 weeks post-surgery if no ACT or starting 4 weeks post-ACT) from November 2019 to March 2023. RESULTS: Of the initially diagnosed patients with stages I-III PDAC who went for resection, the median follow-up time from surgery was 13 months (range 0.1-214). Positive ctDNA detection rates were 29% (29/100) and 29.6% (45/152) during the MRD and surveillance windows, respectively. Positive ctDNA detection was significantly associated with shorter DFS within the MRD window (median DFS of 6.37 months for ctDNA-positive vs 33.31 months for ctDNA-negative patients; HR: 5.45, P < .0001) as well as during the surveillance period (median DFS: 11.40 months for ctDNA-positive vs NR for ctDNA-negative; HR: 12.38, P < .0001). Additionally, DFS was significantly better with KRAS wildtype status followed by KRASG12R (HR: 0.99, P = .97), KRASG12D (HR: 1.42, P = .194), and worse with KRASG12V (HR: 2.19, P = .002) status. In multivariate analysis, ctDNA detection at surveillance was found to be the most significant prognostic factor for recurrence (HR: 24.28, P < .001). CONCLUSIONS: Perioperative tumor-informed ctDNA detection in PDAC is feasible across all stages and is associated with patient survival outcomes.

NCCN Guidelines® Insights: Rectal Cancer, Version 3.2024.

The determination of an optimal treatment plan for an individual patient with rectal cancer is a complex process. In addition to decisions relating to the intent of rectal cancer surgery (ie, curative or palliative), consideration must also be given to the likely functional results of treatment, including the probability of maintaining or restoring normal bowel function/anal continence and preserving genitourinary functions. Particularly for patients with distal rectal cancer, finding a balance between curative-intent therapy while having minimal impact on quality of life can be challenging. Furthermore, the risk of pelvic recurrence is higher in patients with rectal cancer compared with those with colon cancer, and locally recurrent rectal cancer is associated with a poor prognosis. Careful patient selection and the use of sequenced multimodality therapy following a multidisciplinary approach is recommended. These NCCN Guidelines Insights detail recent updates to the NCCN Guidelines for Rectal Cancer, including the addition of endoscopic submucosal dissection as an option for early-stage rectal cancer, updates to the total neoadjuvant therapy approach based on the results of recent clinical trials, and the addition of a "watch-and-wait" nonoperative management approach for clinical complete responders to neoadjuvant therapy.

Colon Cancer, Version 3.2024, NCCN Clinical Practice Guidelines in Oncology.

Colorectal cancer (CRC) is the fourth most frequently diagnosed cancer and the second leading cause of cancer death in the United States. Management of disseminated metastatic CRC involves various active drugs, either in combination or as single agents. The choice of therapy is based on consideration of the goals of therapy, the type and timing of prior therapy, the mutational profile of the tumor, and the differing toxicity profiles of the constituent drugs. This manuscript summarizes the data supporting the systemic therapy options recommended for metastatic CRC in the NCCN Guidelines for Colon Cancer.

Post-operative Surveillance and Management of Intrahepatic Cholangiocarcinoma Using Circulating Tumor DNA: A Case Report.

Cholangiocarcinomas (CCAs) are a subclass of biliary tract tumors that arise from the epithelial lining of bile ducts. They are subdivided broadly into intra- and extrahepatic CCA, with extrahepatic being the more common. Circulating tumor DNA (ctDNA) is a form of liquid biopsy obtained from dying tumor cells in the peripheral blood. Assays may be tumor-informed or tumor-agnostic, with the former requiring tissue sampling to evaluate detectable mutations present in an individual patient's tumor. Here we present a case of intrahepatic CCA managed with hepatectomy followed by adjuvant chemotherapy, with subsequent surveillance and management guided by tumor-informed ctDNA. A 79-year-old female presented to our hospital in December 2019 with three months of postprandial epigastric abdominal pain. Computed tomography (CT) revealed a 5.7 x 5.2 cm left hepatic lobe mass, and surgical pathology confirmed invasive CCA. She underwent left hepatectomy with hepaticojejunostomy one month after presentation and started adjuvant chemotherapy thereafter. She followed us to our cancer center for standard surveillance along with ctDNA. Her tumor markers were within normal limits, and ctDNA was negative until May 2022, when ctDNA was detected, while CA 19-9 remained normal; CT imaging was without evidence of disease. Positron emission tomography-computed tomography (PET-CT) performed in July 2022 revealed local recurrence at the surgical margin, which was confirmed by an endoscopic biopsy. She began gemcitabine-capecitabine chemotherapy in October 2022, completed four cycles followed by chemoradiation therapy, and is currently at her baseline functional status with no detectable radiologic or molecular evidence of disease.

Circulating Tumor DNA (ctDNA) Clearance May Predict Treatment Response in Neoadjuvant Colorectal Cancer Management.

Background: Circulating tumor DNA (ctDNA) is extracellular DNA released by tumors and has been proposed as a marker of residual disease as well as a predictor of disease recurrence in the adjuvant setting. However, data are lacking on the utility of this biomarker in the neoadjuvant setting. Methods: We performed a retrospective study of stage III and IV colorectal cancer patients receiving neoadjuvant treatment at a single institution. Results: Seventeen patients converted from a positive pre-neoadjuvant ctDNA to a negative ctDNA prior to surgery. Five patients remained persistently positive despite systemic treatment. ctDNA conversion was found to be associated with a higher incidence of favorable treatment effect scores on final surgical pathology. There was no difference in recurrence-free survival in this small population. Furthermore, no added benefit was identified for patients receiving additional neoadjuvant therapy after the time of positive to negative ctDNA conversion. Conclusions: This study highlights the potential utility of ctDNA and the need for prospective trials in the neoadjuvant setting to monitor treatment response and guide decisions on treatment duration.

Mesothelin expression correlates with elevated inhibitory immune activity in patients with colorectal cancer.

The expression of the protein Mesothelin (MSLN) is highly variable in several malignancies, including colorectal cancer (CRC), and high levels are associated with aggressive clinicopathological features and worse patient survival. Colorectal cancer is both a common and deadly cancer; being the third most common in incidence and second most common cause of cancer-related death. While systemic therapy remains the primary therapeutic option for most patients with stage IV (metastatic; m) CRC, their disease eventually becomes treatment refractory, and 85% succumb within 5 years. Microsatellite-stable (MSS) CRC tumors, which constitute more than 90% of patients with mCRC, are generally refractory to immunotherapeutic interventions. In our current work, we characterize MSLN levels in CRC, specifically correlating expression with clinical outcomes in relevant CRC subtypes, and explore how MSLN expression impacts the status of immune activation and suppression in the peritumoral microenvironment. Higher MSLN expression is prevalent in CMS1 and CMS4 CRC subtypes and correlates with higher gene mutation rates across the patient cohorts. Further, MSLN-high patients exhibit increased M1/M2 macrophage infiltration, PD-L1 staining, immune-inhibitory gene expression, enrichment in inflammatory, TGF-ß, IL6/JAK/STAT3, IL2/STAT5 signaling pathways, and mutation in KRAS and FBXW7. Together, these results suggest that MSLN protein is a potential target for antigen-specific therapy and supports investigation into its tumorigenic effects to identify possible therapeutic interventions for patients with high MSLN expressing MSS CRC.

Association between frailty and overall survival among older adults with hepatocellular carcinoma.

INTRODUCTION: Older adults undergoing cancer treatment often experience more treatment-related toxicities and increased risk of mortality compared to younger patients. The role of frailty among older individuals as a predictor of outcomes has gained growing significance. We evaluated the association between frailty and overall survival (OS) in patients with hepatocellular carcinoma (HCC) ≥60 years. MATERIALS AND METHODS: Older adults ≥60 years with HCC enrolled in a prospective single-institution registry underwent a patient-reported geriatric assessment (GA) covering multiple health domains related to prior to their initial medical oncology appointment. Frailty was measured using a 44-item deficit accumulation frailty index. We categorized patients as robust, pre-frail, and frail using standard cutpoints. The primary outcome was overall survival (OS). Univariable and multivariable models were built to evaluate the association between frailty and OS after adjusting for potential confounders. RESULTS: Total of 116 older adults with HCC with a median age of 67 years were enrolled; 82% male, 27% Black, and 78% with stage III/IV disease. Overall, 19 (16.3%) were robust, 39 (33.6%) pre-frail, and 58 (50.1%) frail. There were 76 patients receiving liver directed therapy. Of these, 13 (17%) were robust, 26 (34%) were pre-frail, and 37 (49%) were frail. Over a median follow up of 0.9 years, 53 patients died. After adjusting for age, stage, etiology, and Child-Pugh class, being frail (vs. robust) was associated with worse OS (hazard ratio (HR) 2.6 [95% CI 1.03-6.56]; p = 0.04). DISCUSSION: Half of the participants in this study were frail, which was independently associated with worse survival in adults ≥60 years of age with HCC. Identification of pre-treatment frailty may allow opportunities to guide treatment decisions and prognostication.

Mesothelin expression correlates with elevated inhibitory immune activity in patients with colorectal cancer.

The expression of the protein Mesothelin (MSLN) is highly variable in several malignancies including colorectal cancer (CRC) and high levels are associated with aggressive clinicopathological features and worse patient survival. CRC is both a common and deadly cancer; being the third most common in incidence and second most common cause of cancer related death. While systemic therapy remains the primary therapeutic option for most patients with stage IV (metastatic; m) CRC, their disease eventually becomes treatment refractory, and 85% succumb within 5 years. Microsatellite-stable (MSS) CRC tumors, which affect more than 90% of patients with mCRC, are generally refractory to immunotherapeutic interventions. In our current work, we characterize MSLN levels in CRC, specifically correlating expression with clinical outcomes in relevant CRC subtypes and explore how MSLN expression impacts the status of immune activation and suppression in the peritumoral microenvironment. High MSLN expression is highly prevalent in CMS1 and CMS4 CRC subtypes as well as in mCRC tissue and correlates with higher gene mutation rates across the patient cohorts. Further, MSLN-high patients exhibit increased M1/M2 macrophage infiltration, PD-L1 staining, immune-inhibitory gene expression, enrichment in inflammatory, TGF-ß, IL6/JAK/STAT3, IL2/STAT5 signaling pathways and mutation in KRAS and FBXW7. Together, these results suggest MSLN protein is a potential target for antigen-specific therapy and supports investigation into its tumorigenic effects to identify possible therapeutic interventions for patients with high MSLN expressing MSS CRC.