Patient-derived Organoid Pharmacotyping As A Predictive Tool for Therapeutic Selection in Pancreatic Ductal Adenocarcinoma.

OBJECTIVE: We integrate a new approach to chemosensitivity data for clinically-relevant regimen matching, and demonstrate the relationship with clinical outcomes in a large PDO biobank. SUMMARY BACKGROUND DATA: Pancreatic ductal adenocarcinoma (PDAC) usually recurs following potentially curative resection. Prior studies related patient-derived organoid (PDO) chemosensitivity with clinical responses. METHODS: PDOs were established from pre-treatment biopsies in a multi-institution clinical trial (n=21) and clinical specimens at a high-volume pancreatectomy center (n=74, of which 48 were pre-treated). PDO in vitro chemosensitivities to standard-of-care chemotherapeutics (pharmacotypes) were matched to potential clinically-relevant regimens by a weighted nearest-neighbors analysis. Clinical outcomes were then compared for patients who had well-matched versus poorly-matched treatment according to this metric. RESULTS: Our function matched 91% of PDOs to a standard-of-care regimen (9% pan-resistant). PDOs poorly-matched to the neoadjuvant regimen received would have matched to an alternative in 34% of cases. Patients receiving neoadjuvant chemotherapy well-matched to their pharmacotype experienced improved CA 19-9 response (60% decreased to normal when well-matched, 29% when poorly-matched, P<0.05) and lymph node down-staging (33% N0 after poorly-matched, 69% after well-matched, P<0.05). Patients receiving both well-matched neoadjuvant and adjuvant chemotherapy experienced improved recurrence-free- and overall survival (median RFS 8.5 mo poorly-matched, 15.9 mo well-matched, P<0.05; median OS 19.5 vs. 30.3 mo, P<0.05). CONCLUSION: In vitro PDO pharmacotyping can inform PDAC therapy selection. We demonstrate improved outcomes including survival for patients treated with regimens well-matched to their PDO chemosensitivities. A subsequent prospective study using PDO pharmacotype matching could improve oncologic outcomes and improve quality of life by avoiding therapies not expected to be effective.

Effectiveness of resin infiltration in the management of anterior teeth affected by molar incisor hypomineralisation (MIH): A systematic review and meta-analysis.

OBJECTIVES: To evaluate the effectiveness of resin infiltration in improving the aesthetic appearance of anterior teeth affected by molar-incisor hypomineralisation (MIH). DATA SOURCES: PubMed, Scopus, EMBASE, Web of Science, ScienceDirect, and Cochrane Central Register of Controlled Trials (CENTRAL) were searched from 2009 to 2024. The protocol was registered in the International Prospective Database of Systematic Reviews (PROSPERO CRD42023461909). STUDY SELECTION: Interventional or comparative studies comparing resin infiltration and other treatments in MIH-affected anterior teeth were included. The risk of bias was evaluated using the Risk Of Bias In Non-randomised Studies of Interventions (ROBINS-I tool) and the Risk of Bias 2 (RoB 2.0) tool. Meta-analysis utilized a random-effects model. DATA: Eighteen studies met the inclusion criteria, and twelve were included in the meta-analysis. Resin infiltration showed a higher color difference (ΔE) before and after treatment (mean difference 2.21, 95 % confidence interval [CI] 0.04-4.38, p < 0.001, I2 = 98.61 %, p < 0.001) and better optical improvement (standardised mean difference [SMD] 2.68; 95 %CI 0.30-5.06; p = 0.027, I2 = 97.8 %, p < 0.001) compared to controls. The estimated success rate based on dentist assessment was 92 % (95 %CI 88-95 %, I2 = 17.92 %, p = 0.06). Non-randomised trials showed high (8/14) or moderate (6/14) risk of bias, mainly from confounding and selection issues. Randomised trials had high risk (1/3) or some concerns (2/3) due to missing data. CONCLUSIONS: The findings suggest that resin infiltration significantly improves aesthetic outcomes in MIH-affected anterior teeth, as evidenced by higher colour difference and optical improvement compared to controls. CLINICAL SIGNIFICANCE: While our study shows promising results for resin infiltration, including high success rates and aesthetic improvements, larger-scale studies with longer follow-up periods are necessary to confirm these findings and assess its long-term efficacy.

Pre- and post-surgery: advancements in artificial intelligence and machine learning models for enhancing patient management in infective endocarditis.

Infective endocarditis (IE) is a severe infection of the inner lining of the heart, known as the endocardium. It is characterized by a range of symptoms and has a complicated pattern of occurrence, leading to a significant number of deaths. IE poses significant diagnostic and treatment difficulties. This evaluation examines the utilization of artificial intelligence (AI) and machine learning (ML) models in addressing information extraction (IE) management. It focuses on the most recent advancements and possible applications. Through this paper, we observe that AI/ML can significantly enhance and outperform traditional diagnostic methods leading to more accurate risk stratification, personalized therapies as well and real-time monitoring facilities. For example, early postsurgical mortality prediction models like SYSUPMIE achieved 'very good' area under the curve (AUROC) values exceeding 0.81. Additionally, AI/ML has improved diagnostic accuracy for prosthetic valve endocarditis, with PET-ML models increasing sensitivity from 59% to 72% when integrated into ESC criteria and reaching a high specificity of 83%. Furthermore, inflammatory biomarkers such as IL-15 and CCL4 have been identified as predictive markers, showing 91% accuracy in forecasting mortality, and identifying high-risk patients with specific CRP, IL-15, and CCL4 levels. Even simpler ML models, like Naïve Bayes, demonstrated an excellent accuracy of 92.30% in death rate prediction following valvular surgery for IE patients. Furthermore, this review provides a vital assessment of the advantages and disadvantages of such AI/ML models, such as better-quality decision support approaches like adaptive response systems on one hand, and data privacy threats or ethical concerns on the other hand. In conclusion, Al and ML must continue, through multi-centric and validated research, to advance cardiovascular medicine, and overcome implementation challenges to boost patient outcomes and healthcare delivery.

Clinical Relevance of Cancerization of Ducts in Resected Pancreatic Ductal Adenocarcinoma.

OBJECTIVES: Although prevalent in 50%-90% of pancreatic ductal adenocarcinomas, the clinical relevance of "cancerization of ducts" (COD) remains unknown. METHODS: Pathologists retrospectively reviewed slides classifying prevalence of COD. Histopathological parameters, location of first recurrence, recurrence-free survival (RFS), and overall survival (OS) were collected from the institutional pancreatectomy registry. RESULTS: Among 311 pancreatic ductal adenocarcinomas, COD was present in 216 (69.5%) and more prevalent in the cohort that underwent upfront surgery (75.3% vs 63.1%, P = 0.019). Furthermore, COD was associated with female gender (P = 0.040), advanced T stage (P = 0.007), perineural invasion (P = 0.014), lymphovascular invasion (P = 0.025), and R1 margin (P = 0.009), but not N stage (P = 0.401) or tumor differentiation (P = 0.717). In multivariable regression, COD was associated with less liver recurrence (odds ratio, 0.44; P < 0.005). This association was driven by the cohort of patients who had received preoperative treatment (odds ratio, 0.18; P < 0.001). COD was not predictive for RFS or OS. CONCLUSIONS: Cancerization of ducts was not associated with RFS or OS. Currently underrecognized, standardized implementation into histopathological reports may have merit, and further mechanistic scientific experiments need to illuminate its clinical and biologic impact.

REDISCOVER guidelines for borderline-resectable and locally advanced pancreatic cancer: management algorithm, unanswered questions, and future perspectives.

The REDISCOVER guidelines present 34 recommendations for the selection and perioperative care of borderline-resectable (BR-PDAC) and locally advanced ductal adenocarcinoma of the pancreas (LA-PDAC). These guidelines represent a significant shift from previous approaches, prioritizing tumor biology over anatomical features as the primary indication for resection. Condensed herein, they provide a practical management algorithm for clinical practice. However, the guidelines also highlight the need to redefine LA-PDAC to align with modern treatment strategies and to solve some contradictions within the current definition, such as grouping "difficult" and "impossible" to resect tumors together. Furthermore, the REDISCOVER guidelines highlight several areas requiring urgent research. These include the resection of the superior mesenteric artery, the management strategies for patients with LA-PDAC who are fit for surgery but unable to receive multi-agent neoadjuvant chemotherapy, the approach to patients with LA-PDAC who are fit for surgery but demonstrate high serum Ca 19.9 levels even after neoadjuvant treatment, and the optimal timing and number of chemotherapy cycles prior to surgery. Additionally, the role of primary chemoradiotherapy versus chemotherapy alone in LA-PDAC, the timing of surgical resection post-neoadjuvant/primary chemoradiotherapy, the efficacy of ablation therapies, and the management of oligometastasis in patients with LA-PDAC warrant investigation. Given the limited evidence for many issues, refining existing management strategies is imperative. The establishment of the REDISCOVER registry ( https://rediscover.unipi.it/ ) offers promise of a unified research platform to advance understanding and improve the management of BR-PDAC and LA-PDAC.

Distinctive Pathology Associated With Focal Stenosis of the Main Pancreatic Duct Secondary to Remote Trauma: A Long-term Complication of Seat Belt Pancreatitis.

The radiologic finding of focal stenosis of the main pancreatic duct is highly suggestive of pancreatic cancer. Even in the absence of a mass lesion, focal duct stenosis can lead to surgical resection of the affected portion of the pancreas. We present four patients with distinctive pathology associated with non-neoplastic focal stenosis of the main pancreatic duct. The pathology included stenosis of the pancreatic duct accompanied by wavy, acellular, serpentine-like fibrosis, chronic inflammation with foreign body-type giant cell reaction, and calcifications. In all cases, the pancreas toward the tail of the gland had obstructive changes including acinar drop-out and interlobular and intralobular fibrosis. Three of the four patients had a remote history of major motor vehicle accidents associated with severe abdominal trauma. These results emphasize that blunt trauma can injure the pancreas and that this injury can result in long-term complications, including focal stenosis of the main pancreatic duct. Pathologists should be aware of the distinct pathology associated with remote trauma and, when the pathology is present, should elicit the appropriate clinical history.

Exploring the Clinical Use of Molecular Profiling of Intrahepatic Cholangiocarcinoma in a Comprehensive Multidisciplinary Clinic.

BACKGROUND: Molecular profiling of intrahepatic cholangiocarcinoma (ICC) can detect actionable molecular alterations and guide targeted therapies. We explore the clinical use of molecular profiling of ICC in our comprehensive multidisciplinary clinic. STUDY DESIGN: Patients with a tissue diagnosis of ICC seen between 2019 and 2023 were identified. A retrospective review was performed to identify their molecular profiles and targeted therapy. The association between the detection of actionable molecular alterations and overall survival (OS) from the first clinic visit date was studied. Patients with an OS of less than 2 months were excluded. RESULTS: Among 194 patients with ICC, 125 had molecular profiling. Actionable molecular alterations were detected in 56 (45%) patients, including microsatellite instability (n = 3), high tumor mutational burden (>10 muts/mb; n = 5), isocitrate dehydrogenase 1 and 2 mutations (n = 22 and 6, respectively), BRAF V600E mutations (n = 2), phosphatidylinositol-4,5-bisphosphate 3-kinase, catalytic subunit alpha mutations (n = 7), breast cancer 1 and breast cancer 2 mutations (n = 5), mesenchymal epithelial transition amplification (n = 2), fibroblast growth factor receptor 2 and 3 fusions (n = 13), erb-b2 receptor tyrosine kinase 2 overexpression (n = 6), and receptor tyrosine kinase 1 fusion (n = 1). Twenty-one patients received targeted therapies during their treatment course. Survival analysis revealed that for 120 patients with molecular profiling, the detection of an actionable molecular alteration was associated with improved mean OS (34.1 vs 23.6 months, p = 0.008). Among 70 patients with nonmetastatic ICC, the detection of an actionable molecular alteration was associated with improved mean OS (32.1 vs 27.5 months, p = 0.02). CONCLUSIONS: Actionable molecular alterations were frequently observed in patients with ICC. Detection of actionable alterations was associated with improved OS. The role of targeted therapy needs further exploration in prospective multicenter studies.

Whole-genome versus per-chromosome targeted recombination: Simulations and predicted gains in maize with an integer programming model.

Per-chromosome targeted recombination, with one to two recombinations at specific marker intervals on each chromosome, doubles the predicted genetic gains in biparental populations. We developed an integer programing model to identify where a fixed number of targeted recombinations should occur across the whole genome, without restrictions on the number of targeted recombinations on each chromosome. We compared whole-genome and per-chromosome targeted recombination in 392 biparental maize (Zea mays L.) populations and in simulation experiments. For yield, moisture, test weight, and a simulated trait controlled by 2000 quantitative trait loci (QTL), predicted gains were 8%-9% larger with 10 targeted recombinations across the entire genome than with one targeted recombination on each of the 10 chromosomes. With whole-genome targeted recombination, the number of recombinations on a given chromosome was correlated (r = 0.76-0.91) with the chromosome size (in cM). Simulation results suggested that previous results on gains from targeted recombination relative to nontargeted recombination were too optimistic by around 20%. Because the underlying QTL are unknown, studies on targeted recombination have relied on genomewide marker effects as proxies for QTL information. The simulation results indicated a 25% (for 10 recombinations) to 33% (for 20 recombinations) reduction in response due to the use of genomewide marker effects as proxies for QTL information. Overall, the results indicated that the integer programming model we developed is useful for increasing both the predicted and true gains from targeted recombination, but the predicted gains are likely to overestimate the true gains.

An Approach to Leadership in Academic Medicine: Lessons Learned From the Experience of Dr. John L. Cameron.

OBJECTIVE: Dr. John L. Cameron was appointed the chair of surgery at Johns Hopkins in 1984. He subsequently built the largest group of clinician-scientists anywhere in the world who were focused on pancreatic cancer. MATERIALS AND METHODS: Trainees were selected over the decades to join the group based on characteristics including self-confidence, a sense of humor, a collegial and congenial personality, and a strong previous track record. Resume items such as prior leadership positions, academic achievements, and participation in team sports can all prove to be important predictors for future success. RESULTS: Many of the trainees that were molded by that group have perpetuated its ideals by pursuing academic careers. Dr Cameron's approach can be distilled to 3 key points: work hard and lead by example, make diamonds by applying the right amount of pressure, and serve your people and give the impression that you are working for your trainees and junior people. CONCLUSIONS: With those leadership principles, it should still be possible to build successful academic programs, despite the significant challenges that have arisen.

Detecting Somatic Mutations for Well-Differentiated Pancreatic Neuroendocrine Tumors in Endoscopic Ultrasound-Guided Fine Needle Aspiration with Next-Generation Sequencing.

BACKGROUND: Pancreatic neuroendocrine tumors (PanNETs) exhibit heterogenous behavior, whereby some small tumors are aggressive with a propensity for metastasis. Detection of somatic mutations associated with aggressive biology may help with patient stratification and surgical decision-making in patients with well-differentiated PanNETs. Using next-generation sequencing (NGS), we investigated the feasibility of detecting somatic mutations in endoscopic ultrasound-guided, fine-needle aspiration (EUS-FNA) specimens and determining the mutational concordance between the EUS-FNA specimens and the primary tumors. METHODS: Thirty-eight patients with well-differentiated, nonfunctioning PanNETs were obtained from two tertiary referral centers. Patient demographic characteristics and tumor, clinicopathologic features were collected. Tissue from both the EUS-FNA specimen and the primary tumor was extracted from archival tissue blocks. NGS using a panel of ten genes was performed on both samples. RESULTS: In our series, the median age was 61.1 years. Tumors were predominantly left-sided (60.5%) and unifocal (94.7%). The median tumor size was 2.2 cm. NGS detected somatic mutations in 29% of primary tumors and 36.8% of EUS-FNA specimens. In primary tumors, DAXX/ATRX mutations were predominantly detected (63.6%). In EUS-FNA specimens, MEN1 mutations were predominantly detected (64.3%). Among non-wild-type specimens, mutational concordance was achieved in 31.6% of cases. In 11 patients with a detectable mutation in the primary tumor, a mutation was detected in the EUS-FNA specimen in 45.5% of cases, with a mutational concordance of 54.5%. CONCLUSIONS: NGS can detect somatic mutations in EUS-FNA specimens of well-differentiated PanNETs. Efforts to improve detection sensitivity and mutational concordance are required to overcome current technical limitations.

Oncologic resection of pancreatic cancer with isolated liver metastasis: Favorable outcomes in select patients.

BACKGROUND: Patients with pancreatic ductal adenocarcinoma (PDAC) and liver metastasis are treated with palliative chemotherapy, whereas similar patients with metastatic colorectal cancer are considered for aggressive surgery. METHODS: Using an institutional database, PDAC patients undergoing liver resection for isolated metastasis were identified. Their overall survival (OS), treatment factors, and clinicopathological variables associated with survival were also evaluated. RESULTS: Forty-seven patients underwent curative-intent surgery for metastatic PDAC to the liver between 2000 and 2019. Median OS was 21.9 months from diagnosis. Fourteen patients underwent unplanned resection of radiographically occult liver metastasis during pancreatectomy with median OS of 8.7 months. On the other hand, 29 patients received systemic chemotherapy followed by planned resection; this cohort had the most favorable prognosis following aggressive surgery with median OS being 38.1 months from diagnosis and 24.1 months from surgery. Preoperative chemotherapy (HR = 7.1; p = .002) and moderate to well differentiation of the primary tumor (HR = 3.7; p = .003) were associated with prolonged survival in multivariate analysis, whereas lymph node metastases, response to preoperative therapy, number of liver metastasis, and extent of liver surgery were not. CONCLUSIONS: In select patients with PDAC and isolated liver metastasis, curative-intent surgery can result in meaningful survival. This aggressive approach seems most beneficial in patients following induction chemotherapy.

Resected Early-Onset Pancreatic Cancer: Practices and Outcomes in an International Dual-Center Study.

BACKGROUND: Early-onset pancreatic cancer (EOPC), defined as age ≤ 45 years at diagnosis, accounts for 3% of all pancreatic cancer cases. Although differences in tumor biology have been suggested, available data are sparse and specific treatment recommendations are lacking. This study explores the clinicopathological features and oncologic outcomes of resected EOPC. PATIENTS AND METHODS: Patients with EOPC undergoing resection between 2002 and 2018 were identified from the Heidelberg University Hospital and Johns Hopkins University registries. Median overall survival (OS) and recurrence-free survival (RFS) were analyzed, and prognostic factors were identified. RESULTS: The final cohort included 164 patients, most of whom had pancreatic ductal adenocarcinoma (PDAC, n = 136; 82.9%) or IPMN-associated pancreatic cancer (n = 17; 10.4%). Twenty (12.1%) patients presented with stage 1 disease, 42 (25.6%) with stage 2, 75 (45.7%) with stage 3, and 22 (13.4%) with oligometastatic stage 4 disease. Most patients underwent upfront resection (n = 113, 68.9%), whereas 51 (31.1%) individuals received preoperative treatment. Median OS and RFS were 26.0 and 12.4 months, respectively. Stage-specific median survival was 70.6, 41.8, 23.8, and 16.9 months for stage 1, 2, 3, and 4 tumors, respectively. Factors independently associated with shorter OS and RFS were R1 resections and AJCC stages 3 and 4. Notably, AJCC 3-N2 and AJCC 3-T4 tumors had a median OS of 20 months versus 29.5 months, respectively. CONCLUSION: Despite frequently presenting with advanced disease, oncologic outcomes in EOPC patients are satisfactory even in locally advanced cancers, justifying aggressive surgical approaches. Further research is needed to tailor current guidelines to this rare population.

Conduits in Vascular Pancreatic Surgery: Analysis of Clinical Outcomes, Operative Techniques, and Graft Performance.

OBJECTIVES: We analyze successes and failures of pushing the boundaries in vascular pancreatic surgery to establish safety of conduit reconstructions. BACKGROUND: Improved systemic control from chemotherapy in pancreatic cancer is increasing the demand for surgical solutions of extensive local vessel involvement, but conduit-specific data are scarce. METHODS: We identified 63 implanted conduits (41% autologous vessels, 37% allografts, 18% PTFE) in 56 pancreatic resections of highly selected cancer patients between October 2013 and July 2020 from our prospectively maintained database. Assessed parameters were survival, perioperative complications, operative techniques (anatomic and extra-anatomic routes), and conduit patency. RESULTS: For vascular reconstruction, 25 arterial and 38 venous conduits were utilized during 39 pancreatoduodenectomies, 14 distal pancreatectomies, and 3 total pancreatectomies. The median postoperative survival was 2 years. A Clavien-Dindo grade ≥IIIa complication was apparent in 50% of the patients with a median Comprehensive Complication Index of 29.6. The 90-day mortality in this highly selected cohort was 9%. Causes of mortality were conduit related in 3 patients, late postpancreatectomy hemorrhage in 1 patient, and early liver metastasis in 1 patient. Image-based patency rates of conduits were 66% and 45% at postoperative days 30 and 90, respectively. CONCLUSIONS: Our perioperative mortality of vascular pancreatic surgery with conduits in the arterial or venous system is 9%. Reconstructions are technically feasible with different anatomic and extra-anatomic strategies, while identifying predictors of early conduit occlusion remains challenging. Optimizing reconstructed arterial and venous hemodynamics in the context of pancreatic malignancy will enable long-term survival in more patients responsive to chemotherapies.

Grading Pancreatic Neuroendocrine Tumors Via Endoscopic Ultrasound-guided Fine Needle Aspiration: A Multi-institutional Study.

OBJECTIVES: To identify factors associated with concordance between World Health Organization (WHO) grade on cytological analysis (c-grade) and histopathological analysis (h-grade) of surgical specimen in patients with PanNETs and examine trends in utilization and accuracy of EUS-FNA in preoperatively predicting grade. BACKGROUND: WHO grading system is prognostic in pancreatic neuroendo-crine tumors (PanNETs). The concordance between c-grade and h-grade is reported to be between 50% and 92%. METHODS: A multicenter retrospective study was performed on patients undergoing resection for PanNETs at four high-volume centers between 2010 and 2019. Patients with functional or syndrome-associated tumors, and those receiving neoadjuvant therapy were excluded. Factors associated with concordance between c-grade and h-grade and trends of utilization of EUS-FNA were assessed. RESULTS: Of 869 patients included, 517 (59.5%) underwent EUS-FNA; 452 (87.4%) were diagnostic of PanNETs and WHO-grade was reported for 270 (59.7%) patients. The concordance between c-grade and h-grade was 80.4% with moderate concordance ( Kc = 0.52, 95% CI: 0.41-0.63). Significantly higher rates of concordance were observed in patients with smaller tumors (<2 vs. ≥2cm, 81.1% vs. 60.4%, P = 0.005). Highest concordance (98.1%) was observed in patients with small tumors undergoing assessment between 2015-2019 with a near-perfect concordance ( Kc = 0.88, 95% CI: 0.61-1.00). An increase in the utilization of EUS-FNA (56.1% to 64.1%) was observed over the last 2 decades ( P = 0.017) and WHO-grade was more frequently reported (44.2% vs. 77.6%, P < 0.001). However, concordance between c-grade and h-grade did not change significantly (P = 0.118). CONCLUSION: Recently, a trend towards increasing utilization and improved diagnostic accuracy of EUS-FNA has been observed in PanNETs. Concordance between c-grade and h-grade is associated with tumor size with near-perfect agreement when assessing PanNETs <2cm in size.

Performance of the 7 th and 8 th Editions of the American Joint Committee on Cancer Staging System in Patients with Intraductal Papillary Mucinous Neoplasm-Associated PDAC : A Multi-institutional Analysis.

OBJECTIVE: To validate the 7 th and 8 th editions of the AJCC staging system for patients with invasive carcinomas arising in association with IPMN (IPMN-associated PDAC). BACKGROUND DATA: Although several studies have validated AJCC systems in patients with conventional PDAC, their applicability to IPMN-associated PDAC has not been assessed. METHODS: Two hundred seventy-five patients who underwent resection for IPMN-associated PDAC between 1996 and 2015 at 3 tertiary centers and had data on the size of the invasive component and lymph node status were identified. Concordance probability estimates (CPE) were calculated and recursive partitioning analysis was employed to identify optimal prognostic cutoffs for T and N. RESULTS: The CPE for the 7 th and 8 th editions of the AJCC schema were relatively good (0.64 for both) and similar for colloid and tubular subtypes (0.64 for both). The 8 th edition introduced T1a sub-staging and a new distinction between N1 and N2. The utility of the former was confirmed, although the latter did not improve prognostic discrimination. The successful validation of the 8th edition of the AJCC criteria in patients with tubular and colloid subtypes allowed us to compare these patients in early vs late T and N stages which showed that with advanced disease, the prognostic superiority of colloid tumors over their tubular counterparts diminishes. CONCLUSIONS: Our findings support the use of the AJCC 8 th edition in the IPMN-associated PDAC population, but suggest that certain cutoffs may need to be revisited. In advanced AJCC stages, patients with colloid vs tubular subtypes have comparable prognosis.

Tailoring Adjuvant Chemotherapy to Biologic Response Following Neoadjuvant Chemotherapy Impacts Overall Survival in Pancreatic Cancer.

BACKGROUND: The role of postoperative chemotherapy in patients with resected pancreatic cancer who receive neoadjuvant treatment is unknown. Clinicians use changes in CA19-9 and histopathologic scores to assess treatment response. We sought to investigate if CA19-9 normalization in response to NAT can help guide the need for postoperative treatment. METHODS: Patients with elevated baseline CA19-9 (CA19-9 > 37U/mL) who received NAT followed by surgery between 2011 and 2019 were retrospectively reviewed. Treatment response was determined by CA19-9 normalization following NAT and histopathologic scoring. The role of postoperative chemotherapy was analyzed in light of CA19-9 normalization and histopathologic response. RESULTS: We identified and included 345 patients. Following NAT, CA19-9 normalization was observed in 125 patients (36.2%). CA19-9 normalization was associated with a favorable histopathologic response (41.6% vs 23.2%, p < 0.001) and a lower ypT (p < 0.001) and ypN stage (p = 0.003). Receipt of adjuvant chemotherapy was associated with improved overall survival in patients in whom CA19-9 did not normalize following NAT (26.8 vs 16.4 months, p = 0.008). In patients who received 5FU-based NAT and in whom CA19-9 did not normalize, receipt of 5FU-based adjuvant chemotherapy was associated with improved OS (p = 0.014). CONCLUSION: CA19-9 normalization in response to NAT was associated with favorable outcomes and can serve as a biomarker for treatment response. In patients where CA19-9 did not normalize, receipt of postoperative chemotherapy was associated with improved OS. These patients also benefited from additional 5FU-based postoperative chemotherapy following 5FU-based NAT.