Systemic Chemotherapy Research Articles

Is there a place for surgery in oligometastatic ductal carcinoma of the pancreatic head?

Background: New chemotherapy regimens (gemcitabine / nab-paclitaxel, FOLFIRINOX) have improved overall survival rates in ductal carcinoma, which has renewed the interest in surgical treatment for isolated liver metastases. Aim: To identify the role of surgery in ductal carcinoma of the pancreatic head with liver oligometastases. Methods: We retrospectively analyzed the data from 490 patients with morphologically verified ductal carcinoma of the pancreatic head in two specialized centers, who had undergone pancreatoduodenectomy (PD) from January 2011 to April 2024. In 21 patients, PD was performed simultaneously with liver resection (liver oligometastases were found during the surgery). Results: In the postoperative period after PD with liver resection, compared to that after PD without liver resection, intra-abdominal abscesses were more frequent (4/21 (19.0%) versus 10/469 (2.2%), p = 0.002) and relaparotomy was performed more often by 9.8% [95 confidence interval (CI, Miettinen-Nurminen score method) 0.21–30.3] (3/21 (14.3%) versus 21/469 (4.5%), p = 0.077). The postoperative death rates were comparable (1/21 (4.8%) versus 19/469 (4.1%), p = 0.8). The median overall survival of the patients after PD with liver resection was 11 (95% CI: 6–16) months, and overall 1-, 2-, and 3-year survival rates were 39.2, 16.8 and 7.2%, respectively. In the patients after PD with liver resection without any adjuvant chemotherapy (n = 5), the median overall survival was 6 (95% CI: 5–7) months, and in those with chemotherapy, 13 (95% CI: 6–16) months (p = 0.006). The overall three-year survival of the patients after PD with liver resection and adjuvant chemotherapy was 11.5%. In the patients after PD with liver resection R0, the median overall survival was 13 (95% CI: 6–32) months, with R1 resection 6 (95% CI: 6–7), and with R2 resection 6 (95% CI: 6–7) months (p = 0.021). The median overall survival of patients after PD with liver resection for G1 tumors was 17 (95% CI: 6–32) months. Conclusion: Surgery as a component of combination therapy for oligometastatic pancreatic head cancer can be considered in a certain category of patients with high tumor differentiation grade and mandatory preliminary assessment of the feasibility of R0 surgery and systemic chemotherapy.

A rare case of spinal myeloid sarcoma

Background: Myeloid sarcoma (MS), a rare extramedullary tumor composed of myeloid blast cells, is classified by the World Health Organization as a subtype of acute myeloid leukemia (AML). Isolated, primary, or nonleukemic MS has an incidence of 2/1,000,000 adults and constitutes only 0.7% of all AML cases. MS presentations vary widely, with spinal involvement being rare. Case Description: A-year-old male presented with interscapular pain radiating to the right upper arm/neck but was neurologically intact. Once diagnosed with isolated spinal MS, he underwent a surgical decompression followed by local irradiation, systemic chemotherapy, and bone marrow transplantation. Eight months postoperatively, however, he experienced a graft-versus-host rejection and required additional therapies. Conclusion: Establishing the diagnosis of MS is challenging and typically requires histological confirmation (i.e., the presence of myeloblasts and granulocytic cells). However, optimal treatment strategies remain elusive; despite radiation, chemotherapy, bone marrow transplant/other local therapies, the overall long-term prognosis for MS remains poor.

Effect of performance status on the therapeutic effect of nivolumab in recurrent or metastatic squamous cell carcinoma of the head and neck.

Systemic chemotherapy is the primary treatment strategy for recurrent or metastatic squamous cell carcinoma of the head and neck (RM-SCCHN). Therapeutic strategies are changing considerably with the introduction of molecular-targeted and immune checkpoint inhibitor (ICI) therapies in addition to conventional cytotoxic therapy. The CheckMate-141 and KEYNOTE-048 trials have enabled the use of ICIs as first-line treatment to improve the overall prognosis of RM-SCCHN. However, background factors affecting treatment responses, including performance status (PS), remain poorly defined. Therefore, we investigated the effect of PS in patients treated with nivolumab. We retrospectively reviewed the treatment outcomes and backgrounds of 31 patients with RM-SCCHN who received nivolumab monotherapy between April 2017 and March 2023. The patient background was male/female = 29/2, median age was 68years (range 39-85), PS0/1/2 = 14/15/2, and oral/oropharynx/hypopharynx/larynx = 2/12/12/5. Median overall survival was 8.0months (95% confidence interval [CI]: 4.3-30.6months), median progression-free survival was 3.0months (95% CI 1.7-9.1months), and objective response rate was 22.6% (95% CI 11.1-40.1%). Immune-related adverse events of grade 3 or higher were observed in three patients (9.7%). Eight (29.6%) of the 27 patients (excluding four patients who maintained complete response for over 2 years) were successfully transferred to post-treatment. In the multivariate analysis, Eastern Cooperative Oncology Group (ECOG) PS (Hazard Ratio: 9.87, 95% CI 1.79-54.56) was associated with poor survival. The efficacy of nivolumab is reduced in patients with poor PS.

MTOR inhibitors potentially preserve fertility in female patients with haematopoietic malignancies: a narrative review.

Haematologic malignancies are considered among the more common adolescent and young adult (AYA) cancers. Many female AYA patients with haematopoietic malignancies face impaired fertility. Haematologic malignancies patients tend to be treated with more aggressive systemic chemotherapy than that of solid tumours. In adult women, treatment-related contraception causes age-related fertility loss. Graft-versus-host disease (GVHD) after allogeneic haematopoietic stem cell transplantation is associated with decreased fertility. Ovarian cryopreservation is often indicated for haematopoietic malignancies; however, follicle loss associated with ovarian cryopreservation and ovarian minimal residual disease, which result in the withdrawal of the transplantation, are important issues. These problems may not be fully addressed by conventional methods of fertility preservation, such as oocyte, embryo, and ovarian cryopreservation, leaving room for research into new treatment approaches, such as fertility preservation drugs. In recent years, preclinical studies have shown that mTOR inhibitors may preserve chemotherapy-induced follicular loss, may have follicle-preserving effects on follicle loss associated with cryopreservation and transplantation of ovarian tissue, may have fertility-preserving effects on aging-related infertility. Clinical studies have shown that mTOR inhibitors may have the potential for indirect fertility preservation by controlling GVHD, have a limited anti-tumor effect against haematopoietic malignancies. The purpose of this article is to outline the various issues faced by female survivors of haematopoietic malignancies and discuss the potential of mTOR inhibitors as a safe treatment option. Based on current research, mTOR inhibitors seem promising and innovative fertility preservation agents regarding preclinical conditions, and further study, including clinical trials, should be expected.

Abstract 4124313: An unusual case of pericardial mass

A 30-year-old male electrician presented with two days of fever and positional left shoulder pain and was found to have elevated inflammatory markers and a large pericardial effusion with echocardiographic evidence of tamponade for which he underwent pericardiocentesis. He was discharged on a course of anti-inflammatory therapy with presumed diagnosis of idiopathic pericarditis based on negative cytology. He returned 6 months later with several weeks of upper respiratory infection symptoms as well as new abdominal discomfort and emesis. On presentation, his vital signs were notable for tachycardia to 113 and cardiac exam was notable for tachycardia, regular rhythm, no rubs or murmurs, nondisplaced precordial impulse, normal jugular venous pressure with Kussmaul sign, and pulsus paradoxus of 6. An electrocardiogram showed sinus tachycardia with diffuse ST segment changes (Figure A). His cardiac biomarkers were unremarkable (troponin 21). His labs revealed normocytic anemia with hemoglobin of 11 and erythrocyte sediment rate above assay. Echocardiogram demonstrated a circumferential complex pericardial effusion with echocardiographic evidence of early tamponade (Figure B, C). A pericardiocentesis was attempted with inability to advance wire within pericardial space. A malignancy workup was initiated. CT demonstrated multi-station thoracic and lower cervical lymphadenopathy, moderate left pleural effusion, and an intrapericardial mass with associated pericardial effusion (Figure D). Cardiac magnetic resonance imaging demonstrated a circumferential intrapericardial non-mobile mass measuring up to 22 mm in thickness posteriorly and the mass was isointense to myocardium indicating low-fat content (Figure E). A supraclavicular lymph node biopsy was obtained with immunohistochemical staining positive for WT1 and calretinin, consistent with metastatic epithelioid mesothelioma of pericardial versus pleural etiology (Figure F). A PET-CT subsequently showed a FDG-avid circumferential anterior pericardial mass and multiple pleural-based lesions concerning for metastatic mesothelioma. He was initiated on pemetrexed/carboplatin systemic chemotherapy. With systemic therapy, his disease has been stable for 6 months. Pericardial mesothelioma is a rare malignancy. This case underscores the diagnostic challenges associated with pericardial mesothelioma and the importance of cancer workup as part of the pericardial effusion workup.

Optimal hyperthermic intraperitoneal chemotherapy regimen for advanced and peritoneal metastatic gastric cancer: a systematic review and Bayesian network meta-analysis

BackgroundPeritoneal metastasis is one of the most common modes of spread of gastric cancer. Currently, surgical treatment combined with hyperthermic intraperitoneal chemotherapy (HIPEC) and systemic chemotherapy has demonstrated promising outcomes in both the treatment and prevention of peritoneal metastasis in gastric cancer. However, various HIPEC drug regimens are in clinical use, and their efficacy remains unclear. This study aims to evaluate the effectiveness of different HIPEC drug regimens in patients with advanced gastric cancer to determine the optimal therapeutic approach.MethodsThis study conducted a systematic review and Bayesian network meta-analysis. Patients in the experimental group underwent surgery combined with HIPEC and chemotherapy. The search period covered literature from database inception to June 1, 2024. Hazard ratios (HRs) with 95% confidence intervals (CIs) were used to evaluate overall survival (OS) as the primary outcome. Odds ratios (ORs) with 95% CIs were used to assess overall disease recurrence, peritoneal recurrence, and postoperative morbidity as secondary outcomes. To ensure scientific rigor and transparency, this study has been registered with PROSPERO (CRD42024533948).ResultsA total of 11 randomized controlled trials (RCTs) involving 1092 patients were included. Compared to surgery combined with chemotherapy, the regimens of cisplatin (HRs = 0.52, 95% CI: 0.38-0.73), mitomycin C (HRs = 0.99, 95% CI: 0.55-1.79), cisplatin plus fluorouracil (HRs = 0.60, 95% CI: 0.38-0.95), and oxaliplatin plus 5-fluorouracil (HRs = 0.53, 95% CI: 0.36-0.78) all demonstrated benefits in OS. The cisplatin (ORs = 0.16, 95% CI: 0.03-0.60) and mitomycin C (ORs = 0.03, 95% CI: 0-0.71) regimens also showed advantages in reducing peritoneal recurrence, with no impact on postoperative morbidity. Importantly, the cisplatin regimen was superior to other regimens in terms of OS and overall disease recurrence, achieving a balance between efficacy and safety.ConclusionsCompared to chemotherapy alone, HIPEC treatment shows significant benefits in OS without a notable disadvantage in postoperative morbidity. Although no single HIPEC regimen demonstrated clear benefits across all outcomes, the cisplatin regimen performed well in multiple aspects, indicating its potential for further research and clinical application.Systematic review registrationhttps://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=533948, identifier CRD42024533948.

Late Local Recurrence of Carcinoma <i>in situ </i>- Only Bladder Cancer

Late recurrence (LR) of bladder cancer after radical cystectomy (RC) is rare, and few studies have been conducted. We report a case of local LR of bladder cancer 10.3 years after RC. The pathology at RC was almost carcinoma <i>in situ</i> (CIS) only. The patient underwent metastasectomy, and treatment with an immune checkpoint inhibitor (ICI) achieved a complete response (CR). A 61-year-old woman was referred to our hospital for macrohematuria and bladder irritability in June 2012. She underwent RC along with pelvic lymph node dissection and ileal conduit creation. The pathologic findings were CIS, G2>G3, pT1, pN0. She visited our hospital with complaints of lower abdominal discomfort in November 2022, and recurrence was found on the pelvic floor by abdominal computed tomography. Metastasectomy confirmed metastasis of urothelial carcinoma. As salvage therapy, systemic chemotherapy with a platinum agent and an ICI were administered, leading to CR. Long-term follow-up should be considered for patients with bladder cancer, even for early-stage CIS-only tumors. Metastasectomy could be the primary option for LR of bladder cancer after RC.

BIOS-04. THERAPIES FOR LEPTOMENINGEAL DISEASE: A NETWORK META-ANALYSIS

Abstract INTRODUCTION Leptomeningeal disease (LMD) has limited head-to-head comparison of available therapies, including systemic chemotherapy (SysCT), intrathecal (IT) or intraventricular therapy (ITV), whole-brain radiotherapy (WBRT), or cranio-spinal irradiation (CSI). No network meta-analysis (NMA) of randomized controlled trials (RCTs) of LMD has been reported so far. METHODS NMA was conducted using published LMD RCTs and reported following PRISMA-NMA guidelines. Primary outcome was survival, assessed using hazard ratios (HRs) and 95% confidence intervals (95%CI). Survival times were converted to HRs under exponential distribution assumption. LogHR standard errors were calculated using deaths per RCT arm. P-scores were used to estimate probability of treatment being superior. Analysis was performed in R using frequentist approach, followed by back-transforming logHRs for indirect and direct comparisons. Incremental effects of individual treatment components were estimated using additive model. Heterogeneity and inconsistency were assessed using tau-squared (τ²), I-squared (I²), and Q-statistics. Analyses were performed separately for main subnetwork with disconnected subnetworks accommodated in additive model. RESULTS Seven studies were included, incorporating 7 pairwise comparisons and 9 treatments. 3 subnetworks were identified. Primary subnetwork analysis included 5 studies. Compared to SysCT±RT (reference), logHRs (95%CI) under random effects model were: IT/ITV DepoCyt±SysCT±RT -0.094(-0.468,0.281); IT/ITV methotrexate(MTX)±cytarabine(AraC)±SysCT±RT 0.8567(0.066,1.647). IT/ITV MTX±SysCT±RT 0.318(-0.163,0.798); ITV Thiotepa±SysCT±RT 0.438(-0.294,1.169). Heterogeneity and inconsistency were not detected (τ²=0,I²=0%,Q-statistic=0.57,P=0.45). P-scores were highest for IT/ITV DepoCyt±SysCT±RT (0.894), followed by SysCT±RT (0.769). Disconnected-component-NMA demonstrated incremental logHR: AraC 0.539(-0.347,1.425); IT/ITV DepoCyt 0.052(-0.566,0.670); IT/ITV MTX 0.179(-0.484,0.840); ITV thiotepa 0.298(-0.767,1.362); proton CSI -0.250(-0.726,0.225). No component demonstrated statistically significant incremental benefit, with moderate heterogeneity and adequate fit present (τ²=0.1017,I²=57%,Q-statistic=4.65,P=0.098). CONCLUSIONS IT/ITV DepoCyt±SysCT±RT and SysCT±RT were found most effective. Lack of significant incremental benefit warrants evaluating older therapies in contemporary RCTs.

EXTH-77. INFANT-TYPE HEMISPHERIC GLIOMAS WITH INITIAL RESPONSE FOLLOWED BY RESISTANCE ON TARGETED AGENTS

Abstract Pediatric-type Diffuse High Grade Gliomas (pHGG) are a rare brain tumor with high mortality and need for more effective treatment options. pHGG’s make up only about 10% of CNS tumors but are responsible for a majority of the deaths. Infant-type Hemispheric Gliomas are a subtype of pHGG with tyrosine kinase alterations in genes such as ROS1, ALK, MET, and NTRK1-3. Despite advances in categorization and targeted therapies, the natural history of patients with infant HGG treated with targeted therapy over time needs to be better characterized, including the durability of objective responses. We present a retrospective case series involving two patients diagnosed with Infant-type Hemispheric Gliomas at Arkansas Children’s Hospital from 2022-2024. Each diagnosis was determined based on histology, targeted tumor sequencing, and methylation profiling. Both patients were initially treated with primary surgical resection and systemic chemotherapy. Each patient experienced disease progression. Actionable pathogenic mutations were identified in both patients (a MET alteration in patient 1 who was then started on Cabozantinib, an ALK fusion in patient 2 subsequently treated with Lorlatinib) with an objective disease response in both patients. In both cases, further relapse occurred while on targeted inhibition. Relapse specimen was not available for patient 1, but for patient 2, recurrent tumor sequencing revealed similar genetics from the diagnostic specimen except for a MET copy number gain suggesting the mechanism of resistance in this patient. Infant-type Hemispheric Gliomas with targetable alterations can show meaningful responses to pathway inhibition. Relapse after initial response may warrant additional surgical sample to identify new alterations which can lead to changes in therapy. Larger prospective cohorts are needed to study targeted agents in this population, and early integration during radiation or after initial diagnosis may be needed.

Human Cystic Echinococcosis Treated with Individualised Homoeopathy—A Case Report

AbstractCystic echinococcosis is a chronic, complex and neglected disease caused by the larval form of cestode Echinococcus granulosus. The liver is the most frequently parasitised organ in humans. Percutaneous drainage, systemic chemotherapy and surgery are the therapies available for hydatid cyst treatment where the risks associated with invasive procedures may be particularly high. Therefore, homoeopathic individualised treatment can be a better approach to treating cases of hydatid cysts without any side effects and risks. In the presented case, the patient received homoeopathic medicine Magnesium muriaticum based on individualisation and Medorrhinum as an intercurrent medicine. The homoeopathic treatment resulted in an overall improvement in the health of the patient. Serial ultrasounds also showed a reduction in the cyst size. This case highlights the fact that homoeopathy can be a plausible alternative to conventional treatment like surgery in cases of hydatid cysts along with improvement in the quality of life of patients as represented by EQ-5D-5L. The Modified Naranjo Criteria explicitly depict the potential causal relationship between the treatment and observed changes.

BIOM-58. RE-INDUCTION OF INTRATHECAL CHEMOTHERAPY IN PRIOR RESPONDERS AND CORRELATION WITH CEREBROSPINAL FLUID CIRCULATING TUMOR CELLS

Abstract INTRODUCTION Leptomeningeal carcinomatosis (LMC) is an aggressive form of metastasis, with a historically poor median overall survival. Newer therapies and treatment strategies are improving outcomes, and more long-term responders exist. However, there are limited options for intrathecal (IT) chemotherapy, and re-induction in prior responders may be a reasonable treatment strategy. In addition, quantitative cerebrospinal fluid circulating tumor cells (CSF CTCs) are a valuable tool in LMC, for both surveillance of recurrence and evaluation of response. METHODS We retrospectively identified 10 patients with LMC who showed a response to IT chemotherapy and were followed with quantitative CSF CTCs on a commercially available platform. At progression, patients underwent re-induction of IT chemotherapy, on a twice a week schedule, and were evaluated for response. RESULTS All 10 patients were treated with re-induction IT chemotherapy. Six patients were re-challenged with topotecan, 3 with topotecan + trastuzumab, and 1 with pemetrexed + trastuzumab. Six patients had a primary diagnosis of breast cancer, three with lung cancer and one with ovarian cancer. The median KPS was 70. Eight were female. Prior to re-induction, all 10 had an increase in quantitative CSF CTCs. Only 1/10 had new symptoms, and 5/10 showed imaging changes on MRI. At the time of re-induction, 3/10 also received stereotactic radiosurgery to brain metastases and 2/10 had a change in systemic chemotherapy. 9/10 had improved CSF CTC counts on the next restaging, typically at 8 weeks. The median overall survival from re-challenge was 12.7 months. CONCLUSION Quantitative CSF CTCs were a more sensitive predictor of recurrence than symptoms or imaging, and were a marker of response to re-induction IT chemotherapy. Re-induction showed a durable survival benefit, and is a reasonable treatment strategy in patients who were prior responders

NCOG-24. CHARACTERIZING NEUROTOXICITY ASSOCIATED WITH SYSTEMIC CHEMOTHERAPY IN PATIENTS WITH BREAST CANCER USING DOMAIN-SPECIFIC INTRA-INDIVIDUAL NEUROCOGNITIVE VARIABILITY

Abstract BACKGROUND Systemic chemotherapy is associated with neurotoxicity and neurocognitive functioning (NCF) changes. Intra-individual neurocognitive variability (IIV) is an index of NCF spread/dispersion across neuropsychological tests and can be elevated in patients with breast cancer (BC) after systemic chemotherapy. This study investigated longitudinal IIV changes within NCF domains after chemotherapy to determine whether: (1) IIV for NCF domains are more sensitive to changes than traditional mean-based metrics, and (2) whether changes in domain-specific IIV are associated with changes in mood disturbance or quality of life (QOL). METHODS Prior to and during/shortly after chemotherapy, 37 women with BC were administered a standardized NCF battery including tests within domains of attention/speed of information processing (A/SoP), learning/memory (L/M), and executive functions (EF). Within each domain, the coefficient of variation (CoV) was computed using the standard deviation of normatively-adjusted T-scores while adjusting for intra-individual mean. Patients were assessed for QOL using Functional Assessment of Cancer Therapy-Breast and mood using the STAI and BDI. RESULTS Paired samples t-tests revealed that mean NCF performances declined for L/M (t[36])=-4.44,p<.001,Hedge’s g=.70) and improved for A/SoP (t[36]=3.21,p=.003,g=.29), while CoV increased/worsened for L/M (t[36]=3.82,p<.001,g=.76) but did not change for A/SoP (t[36]=-0.05,p=.959,g=.01). There was no change in EF mean or CoV (ps >.10). No domain mean or IIV change was associated with mood changes (ps>.10). Mean NCF changes were not associated with QOL (ps >.10). Increased/worsened L/M CoV was associated with improved FACT-Breast scale QOL (ρ=.40,p=.020). CONCLUSIONS Both mean- and IIV-based NCF worsened for learning/memory. Discrepancies between mean and IIV change for attention/speed of information processing may be due to differential susceptibility to practice effects. Unexpected associations between learning/memory IIV changes and QOL require further investigation. Future studies are needed to examine NCF dispersion changes across treatment status and in other cancer populations.

Venous thromboembolism among gynecologic cancer patients in Zaria

Cancer is one of the most important acquired risk factors for Venous Thromboembolism (VTE) including Deep Vein Thrombosis (DVT) and Pulmonary Embolism (PE). Patients with active malignancy have up to six-fold increased risk of symptomatic VTE than the general population. The risk of VTE in patients with gynecologic malignancy is especially high because of the nature of the tumor, its pelvic location, associated comorbidities, and systemic chemotherapy. The objective of this study was to determine other risk factors, incidence, clinical presentation, and immediate outcome of treatment of thromboembolism in patients with gynecologic cancers in Ahmadu Bello University Teaching Hospital (ABUTH), Zaria, Nigeria. It was a retrospective cross-sectional descriptive study of gynecologic cancer cases that were diagnosed with VTE while on admission from 2007-2016 in ABUTH. The overall prevalence of clinical VTE was 2.8% in gynaecologic malignancy. All were DVT. Most cases of DVT were present in ovarian cancers with left-sided preponderance. There is a need for the provision of modern imaging equipment to facilitate timely and highly sensitive diagnosis of VTE in low-resource settings. The main limitation of this study was the inability to find any confirmed case of PE.

Pretransplant immunotherapy increases acute rejection yet improves survival outcome of HCC patients with MVI post-liver transplantation.

Immune checkpoint inhibitor (ICI)-based immunotherapy has emerged as the most promising strategy for hepatocellular carcinoma (HCC) downstaging prior to liver transplantation (LT). However, further evidence is required to assess the feasibility and safety of pretransplant ICI exposure. We retrospective analyzed 159 HCC patients who underwent LT at our institution from June 2019 to December 2023, and 39 recipients (39/159, 24.5%) received pretransplant ICI therapy. The perioperative acute rejection rate and rejection-related mortality rate in the ICI group were 23.1% (9/39) and 12.8% (5/39), respectively, which were significantly higher than those in the non-ICI group, at 5% (6/120, P = 0.002) and 0% (0/120, P = 0.001). There was no significant difference in the 90-day post-transplant overall survival (OS) (P = 0.447) and recurrence-free survival (RFS) (P = 0.723) between these two groups. We found 37.1% (59/159) recipients were found to have microvascular invasion (MVI), no matter whether the HCC tumor is within Milan criteria or not. Notably, though MVI was identified as a risk factor for the LT recipients, pretransplant ICI exposure appeared to be a protective factor for HCC patients with MVI which benefits its overall survival. Besides, the RFS and OS in the ICI exposure recipients with MVI were comparable to the non-ICI exposure recipients without MVI. However, no synergistic anti-tumor effects were observed with pretransplant ICI immunotherapy when combined with locoregional of TACE, HAIC, RFA and systematic of lenvatinib or sorafenib downstaging treatments, nor with post-transplant adjuvant of systematic or FOLFOX chemotherapy. Further comprehensive studies are needed to balance the dual natural effects of immunotherapy by optimizing downstaging protocols and patient selection to reduce acute rejection and improve long-term survival.

DDEL-02. PRECLINICAL EFFICACY OF IL13RΑ2-TARGETING POLYPEPTIDE-DRUG CONJUGATE (SELF-DEPOTTM ONCOPDC) IN GLIOBLASTOMA AND DIFFUSE INTRINSIC PONTINE GLIOMA

Abstract Glioblastoma (GBM) and diffuse intrinsic pontine glioma (DIPG) are currently incurable cancers. Systemic chemotherapy shows limited efficacy because of the intact blood-brain barrier. Convection-enhanced delivery (CED) offers promise by concentrating high doses of chemotherapeutics directly within these tumors. However, drugs administered via CED often face challenges in confirming precise target delivery and are quickly cleared by increased interstitial fluid flow and drug efflux transporters. This highlights the urgent need for innovative drugs that demonstrate target specificity and prolonged retention capabilities. Intrinsically disordered polypeptides (IDPs), derived from tropoelastin, self-assemble into water-insoluble structures with extended retention properties triggered by body temperature. IL13Rα2, differentially amplified in U87MG GBM and SF8628 DIPG cells, serves as a target for therapeutic intervention. An IL13Rα2-targeting IDP (XM161) was developed by incorporating IL13Rα2 binding sequences into the IDP domains. XM161 demonstrated high selectivity in binding to IL13Rα2, with Kd values of 1,786 nM for IL13Rα1 and 12.8 nM for IL13Rα2. Conjugation of XM161 with SN38, a potent topoisomerase I inhibitor, resulted in XM161-SN38, which remained in a dissolved state up to 50°C but formed insoluble aggregates above 27°C in the presence of cerebrospinal fluid. XM161-SN38 exhibited strong cytotoxicity against U87MG and SF8628 cells, with IC50 values of 14.2 nM and 0.48 nM, respectively. Importantly, XM161-SN38 demonstrated efficacy in overcoming Temozolomide resistance in T98G GBM cells, with IC50 values of 3.35 nM compared to 10.87 nM for unconjugated SN38. In orthotopic xenograft models established in BALB/cSlc-nu/nu male mice using U87MG-Luc2 cells, three doses (3 x 0.95 μg SN38 equivalents) of XM161-SN38 delivered via CED were well tolerated and significantly extended median survival to over 65 days, providing a notable survival benefit compared to untreated controls (42 days) and Topotecan-treated group (42.5 days). These findings validate the feasibility and therapeutic potential of XM161-SN38 for GBM treatment. Ongoing studies are underway to investigate the safety and pharmacokinetics of XM161-SN38 in tumor-naive mouse brains.

NCMP-22. CO-OCCURRENCE OF MULTIPLE SCLEROSIS AND HODGKIN LYMPHOMA. IS THERE A COMMON PATHOPHYSIOLOGY?

Abstract BACKGROUND Multiple sclerosis (MS) and Hodgkin lymphoma (HL) share common epidemiology, genetics and immunological factors. Both affect immune activation, cell proliferation and lymphocyte-mediated immunity. However, occurrence of these two distinct clinical conditions is rare. We present a case of a woman with transverse myelitis fulfilling criteria for MS with synchronous HL. CASE REPORT A 37-year-old woman presented to the emergency room with bilateral leg weakness, numbness and urinary retention. A contrasted MRI of the brain and thoracic spine showed non-specific, non-enhancing white-matter lesions in the brain, and patchy areas of peripheral contrast-enhancement with T2-hyperintensity in the thoracic cord. Treatment with steroid infusion resulted in mild improvements of leg weakness and numbness. Cerebrospinal fluid (CSF) demonstrated oligoclonal bands (OCB) and increased IgG index. Serum was positive for JCV antibody. Due to the atypical MRI findings, namely the peripheral nature of thoracic contrast-enhancement, we were concerned for other inflammatory or autoimmune etiologies. A computed tomography of the chest, abdomen and pelvis revealed a large mediastinal mass and enlarged lymph nodes. A biopsy revealed classic HL. Three-months later, a follow-up MRI brain showed worsening contrast-enhanced lesions. A repeat CSF study revealed normal OCBs and IgG index. CSF was negative for malignant cells and JC virus DNA. To rule out a rare possibility of central nervous system HL, a biopsy of an enhancing brain lesion was obtained, which showed focal gliosis and focal perivascular lymphocytic infiltrates. No malignant cells were observed. She was diagnosed with multiple sclerosis and started systemic chemotherapy (doxorubicin, bleomycin, dacarbazine and vinblastine) for HL. CONCLUSIONS We report a case of an atypical transverse myelitis with HL. Although familial genetic clustering has been described, other potential common risk-factors between MS and HL are Epstein-Barr Virus infection and immunologic overlap, particularly in the context of lymphocyte-mediated immunity.

PATH-34. IT NEVER RAINS BUT IT POURS - DIAGNOSING ANAPLASTIC PLEOMORPHIC XANTHASTROCYTOMA TWICE IN A FORTNIGHT - OUR EXPERIENCE IN A RESOURCE CONSTRAINED SETTING

Abstract Grade 3 Pleomorphic Xanthastrocytoma is a rare tumour (less than 1% of all astrocytic glial neoplasms). Present most commonly with seizures. Surgery and Radiation remain the mainstay of treatment with no clear role for traditional systemic chemotherapies; BRAF inhibitors show some benefit. We report two cases who were diagnosed within a month of each other - one was initially diagnosed in 2017- presented with altered smell, headache and diplopia. Found to have a well-defined lobulated heterogeneously enhancing suprasellar parasellar lesion. After Gross Total Resection, was diagnosed from various centers as Anaplastic Ependymoma WHO Grade III; Gllioblastoma WHO Grade IV; Anaplastic Pleomorphic Xanthastrocytoma WHO Grade III. Based on immunohistochemistry, was considered Anaplastic Ependymoma WHO Grade III. Spine screening was negative; received adjuvant Radiation 60Gy in 30 fractions. After a disease free interval of 6 years, developed a recurrence at the post op site. He underwent repeat decompression and the histopathology showed Grade 3 Pleomorphic Xanthastrocytoma. Immunohistochemistry- OLIG2: diffuse positive; R132H p.IDH1: negative; ATRX: intact nuclear expression; Mismatch repair proteins (MSH2, MSH6, MLH1, PMS2); intact nuclear expression; MIB-1 labelling index: 10-12%; H3 p.K27M: negative; GFAP: variable positivity; Podoplanin and p53 shows focal positivity; EMA, CD 34 are negative. He competed Reirradiation in January 2024. He is asymptomatic and on follow up. The second case -15 year old boy presented with episodes of absence seizures. Imaging showed a predominantly extraaxial lesion at tentorial apex. He underwent decompression and histopathology showed Grade 3 Pleomorphic Xanthastrocytoma. Immunohistochemistry - cells positive for S100 and variably positive for GFAP, OLIG2 and vimentin; ATRX: Retained expression, IDH1p.R132H, EMA, Synaptophysin, Neu N: Negative, p53: Focally positive, CD34: Positive in few tumour cells, Ki-67: 14-16 %.V600 mutation detected in the BRAF gene. Had Adjuvant RT 60 Gy in 30 fractions -completed in March 2024. MRI at 1 month - no significant change in overall tumour burden compared to post operative MRI. Was offered Dabrafenib with Trametinib.

An Atypical Case of Pancreatic Cancer with Mesenchymal Differentiation in a Patient with Primary Lung Adenocarcinoma: Insights into Tumor Biology and Novel Therapeutic Pathways

Background: Pancreatic cancer is among the malignancies with the poorest prognosis, largely due to its aggressive nature and resistance to conventional therapies. Case Summary: This report describes the case of a 69-year-old male patient with stage IV primary lung adenocarcinoma presenting with high levels of programmed death-ligand 1 (PD-L1). Simultaneously, abdominal computed tomography (CT) showed a dilated pancreatic duct at the level of the pancreatic head and a hypodense lesion in the uncinate process involving the superior mesenteric artery. Fine-needle aspiration (FNA) of the pancreatic lesions was negative. After three cycles of chemoimmunotherapy, positron emission tomography–computed tomography (PET-CT) showed complete remission of the lung nodules, lymphadenopathy, and pleural thickening, as well as a decrease in the size of the pancreatic lesion. After another six months, a PET-CT scan showed a focal increased uptake in the pancreatic mass in the same location, indicating disease progression. A core biopsy of the pancreatic tumor showed atypical spindle cell morphology with positive staining for vimentin, characteristic of mesenchymal differentiation with no apparent epithelial features. Comprehensive molecular profiling through Caris Molecular Intelligence® revealed four genes with actionable mutations in the pancreatic tissue, including KRAS (p.G12D) and TP53 (p.R175H). These molecular findings suggested the diagnoses of sarcomatoid carcinoma and conventional pancreatic ductal adenocarcinoma with epithelial–mesenchymal transition. Primary mesenchymal tumors and neuroendocrine neoplasms were excluded because immunohistochemistry was negative for anaplastic lymphoma kinase (ALK), smooth muscle actin (SMA), desmin, CD34, signal transducer and activator of transcription 6 (STAT6), S100, HMB45, CD117, discovered on GIST-1 (DOG1), CD56, progesterone, and synaptophysin. However, despite multiple rounds of systemic chemotherapy, immunotherapy, and radiation, his pancreatic disease rapidly deteriorated and metastasized to the liver and bone. Conclusions: Despite multiple lines of treatment, the patient’s condition worsened and he succumbed to his pancreatic malignancy. This study highlights the clinical characteristics, diagnosis, and treatment of rare pancreatic cancer, emphasizing the importance of molecular testing and histopathological biomarkers in personalizing treatment. It also provides insights into promising therapeutic approaches for similar cases with an unusual presentation.

Combined Nabpaclitaxel pressurized intraPeritoneal aerosol chemotherapy with systemic Nabpaclitaxel-Gemcitabine chemotherapy for pancreatic cancer peritoneal metastases: protocol of single-arm, open-label, phase II trial (Nab-PIPAC trial).

Current therapies show limited efficacy against peritoneal metastases (PM) from pancreatic cancer. Pressurized intra-peritoneal aerosol chemotherapy (PIPAC) has emerged as a novel intraperitoneal drug delivery method. Recently, a dose-escalation study identified the safe dose of Nabpaclitaxel for PIPAC administration, an ideal intraperitoneal chemotherapy agent against pancreatic cancer. Combining systemic NabPaclitaxel-Gemcitabine with NabPaclitaxel-PIPAC may enhance disease control in pancreatic cancer patients with PM. The Nab-PIPAC trial is a single-center, prospective, open-label, phase II study (ClinicalTrials.gov identifier: NCT05371223). Its primary goal is to evaluate the antitumor activity of the combined treatment based on Disease Control Rate (DCR) using RECISTv.1.1 criteria. Secondary objectives include feasibility, safety, pathological response, progression-free and overall survival, nutritional status, quality of life, pharmacokinetics of NabPaclitaxel-PIPAC, and PM molecular evolution via translational research. The treatment protocol consists of three courses, each with two cycles of intravenous NabPaclitaxel-Gemcitabine and one cycle of NabPaclitaxel-PIPAC, with standard metastatic pancreatic cancer doses for the former and 112.5 mg/m2 for the latter. Sample size follows Simon's two-stage design: 12 patients in stage one and 26 in stage two (80 % power, 0.1 alpha). Partial results will be available after first stage enrollment. This trial aims to determine the antitumor efficacy and safety of combining NabPaclitaxel-PIPAC with systemic NabPaclitaxel-Gemcitabine in pancreatic cancer patients with PM.

Negative Impact of Systemic Therapy on Survival in Patients Undergoing Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy for Low-Grade Metastatic Appendiceal Adenocarcinoma.

Despite studies demonstrating that patients with peritoneal metastases from low-grade appendiceal adenocarcinoma (AA) do not respond well to systemic chemotherapy (SC), patients frequently undergo combination of SC with cytoreductive surgery/hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) regardless of grade. A nationwide retrospective analysis using the National Cancer Database evaluated patients with AA with peritoneal metastasis from 2016 to 2021. Cox proportional hazards model was used to evaluate the impact of SC in addition to CRS/HIPEC on overall survival (OS) stratified by tumor grade. A total of 1,449 patients were included: 481 low-grade, 428 intermediate-grade, and 540 high-grade tumors. Clinical variables, such as age, sex, and comorbidity index, were similar across tumor grades. Cytoreductive surgery/hyperthermic intraperitoneal chemotherapy without SC was utilized in 65.73% of low-grade cases compared with 41.01% in intermediate-grade and 11.11% in high-grade cases. Systemic chemotherapy was utilized alone in 17.74% and with CRS/HIPEC in 16.53% of low-grade cases. In adjusted survival analysis, addition of SC to CRS/HIPEC was associated with worse OS for patients with low-grade AA (hazard ratio [HR] 2.77, 95% confidence interval [CI] 1.18-6.50) but not for intermediate (HR 1.65, 95% CI 0.82-3.35) and high-grade tumors (HR 1.18, 95% CI 0.67-2.45). The addition of time to definitive surgery variable nullified the negative impact of adding SC to CRS/HIPEC in low-grade AA (HR 1.76, 95% CI 0.68-4.53). Negative OS impact of SC may be mediated by delays in effective surgical/intraoperative therapy. If CRS/HIPEC is planned for patients with metastatic low-grade AA, avoiding SC may facilitate earlier surgical intervention and improve survival.