Surgical Resection Of Tumor Research Articles

Retrospective study evaluating factors influencing cancer recurrence following surgical resection of pancreatic neuroendocrine tumours (PanNETs)

Retrospective study evaluating factors influencing cancer recurrence following surgical resection of pancreatic neuroendocrine tumours (PanNETs)

PREDICTORS OF POSTOPERATIVE COMPLICATIONS AND FUNCTIONAL OUTCOMES IN PEDIATRIC PATIENTS WITH SURGICALLY TREATED FOURTH VENTRICLE TUMOR

Background Tumors of fourth ventricle are frequently treated pathologies in pediatric neurosurgery. Data regarding predictors for permanent neurological deficits, long-term functional outcomes, cerebellar mutism (CM), the extent of resection (EOR), and oncological outcomes are scarce. We attempt to contribute to this topic with analysis of our institutional cohort. Methods A retrospective single-center study of patients aged ? 19 years who underwent primary surgical resection of fourth ventricular tumor over a 15-year period (2006–2021). Predictors analyzed included: age, gender, surgical approach, anatomical pattern, tumor grade, EOR, tumor volume, and others as appropriate. Results 106 patients were included (64 males, mean age 7.3 years). Rate of permanent neurological deficit was 24.2%; lateral tumor extension (p = 0.036) and tumor volume greater than 38 cm3 (p = 0.020) were significant predictors. Presence of deficit was the only significant predictor of reduced (less than 90) Lansky score (p = 0.005). CM occurred in 20.8% of patients and was influenced by medulloblastoma histology (p = 0.011), lateral tumor extension (p = 0.017), and male gender (p = 0.021). No significant difference between transvermian and telovelar approach in development of CM was detected (p = 0.478). No significant predictor was found for EOR. EOR was not found to be significant predictor of overall survival for both low-grade and high-grade tumors, however, gross total resection (GTR) was protective against tumor recurrence compared to near-total or subtotal resection (p < 0.001). Survival was found to be better in older patients (? 7.0 years, p = 0.019). Conclusion The overall rate of postoperative complications remains high due to the eloquent localization. Older patients (>7 years) have been found to have better outcomes and prognosis. Achieving GTR whenever feasible and safe has been shown to be critical for tumor recurrence. CM was more common in patients with medulloblastoma, and in patients with tumors extending through the foramen of Luschka. The telovelar approach uses a safe and anatomically sparing corridor, however, it has not been associated with a lower incidence of CM and neurological sequelae in our series, showing that each case should be assessed on an individual basis.

MANAGEMENT OF EXTRAMEDULLARY INTRADURAL SPINAL TUMORS

Spinal tumors are relatively uncommon, accounting for approximately 5%–10% of all central nervous system tumors, with an estimated 70%–80% being located in the intradural extramedullary space. The most common intradural extramedullary tumors are schwannomas, followed by meningiomas. Other less common intradural extramedullary tumors include myxopapillary ependymomas. The clinical presentation of these tumors is often rather nonspecific, and clinicians must maintain a high index of suspicion when evaluating patients with chronic back pain. Approximately 50% of affected individuals experience nonspecific back pain, whereas radiating pain, motor deficits, and sensory loss often progress gradually. This study examines the surgical management of intradural spinal tumors treated in our department, focusing on surgical techniques Some of these benign lesions can pose a surgical challenge due to their location to spinal cord, tumor consistency (densely mineralized / calcified). Posterior approaches involving laminectomy while preserving facet joints are typically sufficient for the surgical resection of dorsal and dorsolateral tumors. In conclusion the total surgical removal of these tumors while preserving neurological function remains can pose a surgical challenge especially for those that are densely calcifed and situated anterolateral to spinal cord, but employing standard microsurgical techniques often makes these resections possible.

Rational Design of a Tandem Activatable Fluorescent Probe for Differential Diagnosis and Therapeutic Assessment of Hepatocellular Carcinoma.

Hepatocellular carcinoma (HCC) is a formidable disease, distinguished by its high aggressiveness and dismal outcomes. Although leucine aminopeptidase (LAP) has been widely employed as a biomarker in biological imaging of HCC, it is still susceptible to interference from false-positive signals activated in injured liver tissues. In this study, based on the significant difference of GSH levels in alcohol-damaged liver tissues and tumor tissues, a dual-tandem activatable probe (PCLT) was designed for differential diagnosis and treatment guidance of HCC by near-infrared fluorescence (NIRF) imaging. This probe comprised a dual-locked hemicyanine dye decorated with a tetraethylene glycol chain and dual-recognition unit of glutathione (GSH) and LAP, which could be sequentially cleaved by GSH and LAP to restore its NIRF signal. PCLT excellently discriminated orthotopic HCC from ALI far earlier (7 days) than histological analysis (28 days) and exhibited higher specificity toward early orthotopic HCC than the single-locked probe (PCL). In addition, PCLT is capable of accurately delineating the tumor contour, assisting in surgical resection of HCC tumors under fluorescence visualization, and noninvasively assessing the antitumor effect of HCC chemotherapy during ferroptosis, thereby presenting promising clinical implications for clinical diagnosis and therapy of HCC.

Roles of MRI evaluation of pelvic recurrence in patients with rectal cancer.

Developments in the multidisciplinary treatment of rectal cancer with advances in preoperative magnetic resonance imaging (MRI), surgical techniques, neoadjuvant chemoradiotherapy, and adjuvant chemotherapy have had a significant impact on patient outcomes, increasing the rates of curative surgeries and reducing pelvic recurrence. Patients with pelvic recurrence have worse prognoses, with an impact on morbidity and mortality. Although local recurrence is more frequent within 2 years of surgical resection of the primary tumor, late recurrence may occur. Clinical manifestations can vary from asymptomatic, nonspecific symptoms, to pelvic pain, bleeding, and fistulas. Synchronous metastatic disease occurs in approximately 50% of patients diagnosed with local recurrence. MRI plays a crucial role in posttreatment follow-up, whether by identifying viable neoplastic tissues or acting as a tool for therapeutic planning and assessing the resectability of these lesions. Locally recurrent tissues usually have a higher signal intensity than muscle on T2-weighted imaging. Thus, attention is required for focal heterogeneous lesions, marked contrast enhancement, early invasive behavior, and asymmetric appearance, which are suspicious for local recurrence. However, postsurgical inflammatory changes related to radiotherapy and fibrosis make it difficult to detect initial lesions. This study therefore aimed to review the main imaging patterns of pelvic recurrence and their implications for the surgical decision-making process. CRITICAL RELEVANCE STATEMENT: MRI plays a crucial role in the posttreatment follow-up of rectal cancer, whether by identifying viable neoplastic tissues or by acting as a tool for therapeutic planning. This study reviewed the main imaging patterns of pelvic recurrence. KEY POINTS: MRI aids in surgical planning and the detection of pelvic recurrence and postoperative complications. Being familiar with surgical techniques enables radiologists to identify expected MRI findings. Patterns of rectal cancer recurrence have been categorized by pelvic compartments. Neoplastic tissue may mimic postsurgical and postradiotherapy changes. Resectability of pelvic recurrence is highly related to lesion location.

ANGI-08. SPATIAL TRANSCRIPTOMIC COMPARISONS OF GLIOBLASTOMA TISSUE REVEAL UPREGULATION OF NEURODEVELOPMENTAL PATHWAYS AND SYNAPTIC GENES IN INFILTRATING TUMOR CELLS

Abstract Glioblastoma remains one of the deadliest brain malignancies. First-line therapy consists of maximal surgical tumor resection, chemotherapy, and radiotherapy. Malignant cells escape surgical resection by migrating into the surrounding healthy brain tissue, where they give rise to the recurrent tumor. Gene expression profiling allows glioblastoma tumor cores to be classified into mesenchymal, proneural, and classical subtypes, each with distinct genetic alterations and cellular compositions. In contrast, the adjacent brain parenchyma where infiltrating malignant cells escape surgical resection is less characterized in patients. Using single-cell and multicellular resolution spatial transcriptomics on tissues from both the tumor core and infiltrated brain tissue (n = 11), we compared the transcriptional profiles of malignant cells in these regions. Malignant cells near regions with microvascular proliferation showed increased expression of genes related to vascular homeostasis. Within tumor cores, proneural and mesenchymal subtypes exhibited distinct spatial gene expression patterns, although these differences were reduced in the infiltrated brain tissue, apart from gene expression due to chromosomal alterations specific to the proneural subtype. We identified two transcriptional patterns of brain infiltration, with the dominant pattern showing a transition from mesenchymal to proneural states. This transition was accompanied by increased expression of genes linked to neurodevelopmental pathways and glial cell differentiation. Additionally, one gene module upregulated in infiltrating malignant cells was predictive of poor patient survival and enriched for genes associated with differentiated neuronal cells. Together, our findings provide an updated view of the spatial landscape of glioblastomas and infiltrated brain tissue, furthering our understanding of the malignant cells that invade healthy brain. This insight offers new avenues for targeted therapy after surgical resection of the primary tumor.

A Novel Liver Metastasis Score for Patients Undergoing Surgical Resection of Gastroenteropancreatic Neuroendocrine Tumors: A Multi-institutional Study.

Liver metastasis impacts survival in patients with gastroenteropancreatic neuroendocrine tumors (GEP-NETs); however, current guidelines lack consensus on post-resection surveillance and adjuvant therapy. A comprehensive risk stratification tool is needed to guide personalized management. We aimed to develop and validate a predictive model for liver metastasis risk after surgical resection of GEP-NETs that incorporates pathological factors and adjuvant therapy. Patients with GEP-NETs who underwent surgical resection with curative intent at three major Chinese hospitals (2010-2022) were identified. Univariable and multivariable Cox regression analysis identified independent risk factors of liver metastasis. The liver metastasis score (LMS) was developed using weighted risk factors and validated by tenfold cross-validation. Among the 724 patients included in the analytic cohort, liver metastasis occurred in 66 patients (9.1%) at a median of 36 months; patients with liver metastasis had a worse 5-year overall survival (no liver metastasis 63.6% vs. liver metastasis 95.8%; p<0.001). Independent predictors were Ki-67 index (hazard ratio [HR] 10.36 for Ki-67 3-20%, HR 18.30 for Ki-67 >20%, vs. <3%), vascular invasion (HR 5.03), lymph node metastases (HR 2.24), and lack of adjuvant therapy (HR 3.03). The LMS demonstrated excellent discrimination (C-index 0.888) and stratified patients into low, intermediate, and high-risk relative to 5-year risk of liver metastasis: 2.9%, 20.8%, and 49.7%, respectively (p<0.001). The novel LMS effectively predicted the risk of liver metastasis after surgical resection of GEP-NETs. This validated model can help guide personalized surveillance and adjuvant treatment strategies, potentially improving outcomes for high-risk patients.

Tellurium-Doped Bioactive Glass Induces Ferroptosis in Osteosarcoma Cells Regardless of FSP1

Human osteosarcoma (OS) is a rare tumor predominantly affecting long bones and characterized by a poor prognosis. Currently, the first line of intervention consists of the surgical resection of primary tumors combined with radiotherapy and chemotherapy, with a profound impact on the patient’s life. Since the surgical removal of OS frequently results in a large resection of bones, the use of biomaterials to sustain the stability of the remaining tissue and to stimulate bone regeneration is challenging. Moreover, residual neoplastic cells might be responsible for tumor recurrence. Here, we explored the potential of tellurium-ion-doped bioactive glass as a novel therapeutic intervention to both eradicate residual malignant cells and promote bone regeneration. Bioactive glass (BAG) has been extensively studied and employed in the field of regenerative medicine due to its osseointegration properties and ability to improve bone tissue regeneration. We found that the incorporation of tellurium (Te) in BAG selectively kills OS cells through ferroptosis while preserving the viability of hBMSCs and stimulating their osteodifferentiation. However, the mechanism of Te toxicity is still unclear: (i) Te-BAG generates lipid-ROS through LOXs activity but not iron overload; (ii) Te-dependent ferroptosis is mediated by GPX4 down-regulation; and (iii) the anti-ferroptotic activity of FSP1 is abrogated, whose expression confers the resistance of OS to the canonical induction of ferroptosis. Overall, our data show that Te-doped bioglass could represent an interesting biomaterial with both pro-ferroptotic activity towards residual cancer cells and pro-osteoregenerative activity.

Outcome and survival analysis of pulmonary metastasectomy for primary sarcoma with pulmonary metastases.

Sarcomas are rare malignancies, accounting for approximately 1% of all cancers. Pulmonary metastases are the most preferential site for distant metastasis in malignant soft tissue sarcomas. Despite the lack of evidence from large randomized trials to support treatment guidelines, surgical resection of resectable metastatic tumors remains the current standard of care. This study aimed to explore the survival status of patients with soft tissue sarcoma after resection of pulmonary metastases. This study is a retrospective analysis of patients who mestastasectomy by means of lobar or sublobar resections at National Taiwan University Hospital and its branches. The statistical and investigation period was from February 2007 to December 2020. Among 110 samples during the investigation period, the overall 5-year survival rate was 62.9%, which was higher than the 15%-50.9% reported previously. A disease-free interval of more than 12 months and the occurrence of local recurrence of sarcoma at the time of resection of pulmonary metastases are associated with overall survival. Most of the samples were treated with minimally invasive surgery (VATS), and therefore, most patients had a shorter hospital stay and better postoperative recovery. For pulmonary metastatic sarcoma, pulmonary metastasectomy is a relatively safe treatment method with short hospital stay and short ICU stay. The results of this study suggest that VATS is preferred over thoracotomy, but further observations are needed to confirm these findings.

Long-Term Outcomes of Minimally Invasive Endoscopic Versus Sternotomy Surgical Resection of Primary Cardiac Tumors.

Primary cardiac tumors are uncommon, often benign, but can be potentially life threatening. Minimally invasive endoscopic (ENDO) techniques have been shown to be a feasible alternative for tumor resection compared with conventional sternotomy (CS). This study compared the clinical and surgical outcomes of a small series of patients undergoing cardiac tumor resection operations. Between November 2009 and December 2022, 34 consecutive patients underwent cardiac tumor resection using either ENDO (n = 21) or CS (n = 13) techniques. We compared early perioperative outcomes, echocardiographic outcomes, and long-term clinical and tumor recurrence outcomes. Baseline characteristics were similar between groups; however, the ENDO group included younger patients (56 ± 16 vs 62 ± 17 years) and more female patients (83% vs 53%). The tumor was located in the left atrium (n = 19, 56%), right atrium (n = 5, 15%), or either ventricle (n = 4, 12%). In-hospital mortality and stroke frequency were similar for both groups (n = 0). There was no significant difference in cardiopulmonary bypass or cross-clamp times, respiratory or renal failure, or intensive care unit or hospital lengths of stay. At follow-up (ENDO, 42 [2 to 131] months vs CS, 54 [1 to 156] months), there were no deaths in the ENDO group and 2 patients died in the CS group (P = 0.21). No patients in either group experienced tumor recurrence. In selected patients, both ENDO and CS approaches to primary cardiac tumor resection were safe, effective, durable, and associated with similarly good early and late results.

Unilateral Hemilaminectomy as Primary Treatment for Spinal Cord Tumors: Retrospective Cohort of 38 Cases with a Minimum Follow-Up of 24 Months

To evaluate the efficacy of hemilaminectomy as an approach to intradural tumors and to assess the risk of postoperative spinal instability. This is a retrospective cohort study of 38 patients who underwent surgical resection of intradural tumors between November 2014 and March 2019. Clinical and radiological data were documented in medical records, from which we obtained clinical data including age, gender, tumor etiology, lesion level, type of resection, and postoperative instability during follow-up. Schwannomas and meningiomas were the most commonly treated tumors. The lesion locations were as follows: 8 cervical (21%), 19 thoracic (50%), 10 lumbar (26%), and 1 sacral (3%). The mean follow-up time was 28 months. In all cases, hemilaminectomy allowed for the removal of the tumors without clinical or radiologic evidence of postoperative mechanical instability. Hemilaminectomy was primarily performed on 2 segments but was extended to up to 6 levels in some cases. Unilateral hemilaminectomy is an effective technique that facilitates complete tumor removal with a low rate of postoperative instability in the operated segments.

Radiological Hypertrophic Olivary Degeneration Following Posterior Fossa Tumor Surgery

Hypertrophic olivary degeneration is a rare form of transsynaptic degeneration, caused by injury to the Dentato-rubro-olivary pathway (DROP). Radiologically this manifests as T2 hyperintensity, with or without enlargement of the inferior olivary nucleus (ION). The purpose of the study was to evaluate the incidence, associated imaging characteristics, potential etiologies, latency period, and temporal progression of HOD in patients undergoing surgical resection of posterior fossa tumors (PFTs). A retrospective analysis of patients with PFTs and post-surgical MRI scans was conducted. HOD was diagnosed based on ION signal abnormalities and size changes. Demographics, tumor characteristics, time to HOD onset, involved DROP components, and clinical symptoms were recorded. HOD was seen in 40 (6.2%) patients following PFT surgery. 26 patients were aged 17 or less while the rest were older than 17 years. Medulloblastoma was the most frequently diagnosed tumor type (n=25), followed by pilocytic astrocytoma (n=8), ependymoma (n=6), and high grade glioma (n=1). No statistical association was found between the development of HOD and tumor grade (p=0.882). Ataxia was the most commonly reported clinical symptom (n=15). The time elapsed between surgery and the diagnosis of HOD varied, with median intervals of 1 month, 5 months, and 37 months for different stages. Dentate nucleus was the most commonly affected component of the DROP (n=36). HOD is a frequently overlooked postoperative complication following PFT resection. Increased recognition of HOD by neuroradiologists is essential for timely diagnosis and avoidance of unnecessary diagnostic procedures.

3D-Printed hydrogel scaffolds with drug- and stem cell-laden core/shell filaments for cancer therapy and soft tissue repair.

Treatment of local tumor recurrence and repair of the tissue defects after tumorectomy still remain clinical challenges. Currently, controlled release of therapeutic drugs is one of the widely used approaches to kill the residual and recurrent cancer cells, and stem cell-laden hydrogel scaffolds are promising candidates for soft tissue repair. However, hydrogel scaffolds with the bifunction of controlled release of therapeutic drugs for cancer therapy and loading stem cells for tissue repair are still not well established. In this study, we fabricated a biphasic hydrogel scaffold containing two types of core/shell filaments with drugs and stem cells loaded in the core part of these two filaments. Black phosphorus nanosheets were added to alginate (the shell layer) in the drug-loaded filament, endowing the scaffold with a photothermal effect under near infrared (NIR) laser irradiation. Moreover, NIR could trigger the drug release from the core/shell filaments to achieve photothermal-chemotherapy of cancer. Additionally, stem cells embedded in the core parts of the other filaments could maintain high cell viability due to the protection of the shell layer (pure alginate), which promoted soft tissue regeneration in vivo. Thus, the prepared biphasic scaffold with drug- and stem cell-laden core/shell filaments may be a potential candidate to fill the tissue defects after the surgical resection of tumors to kill the residual and recurrent cancer and repair the tissue defects.

From Spheroids to Bioprinting: A Literature Review on Biomanufacturing Strategies of 3D In Vitro Osteosarcoma Models

AbstractOsteosarcoma (OS) is a rare primary malignant bone cancer affecting mainly young individuals. Treatment typically consists of chemotherapy and surgical tumor resection, which has undergone few improvements since the 1970s. This therapeutic approach encounters several limitations attributed to the tumor's inherent chemoresistance, marked heterogeneity and metastatic potential. Therefore, the development of in vitro platforms that closely mimic the OS pathophysiology is crucial to understand tumor progression and discover effective anticancer therapeutics. Contrary to 2D monolayer cultures and animal models, 3D in vitro platforms show promise in replicating the 3D tumor macrostructure, cell‐cell and cell‐extracellular matrix interactions. This review provides an overview of the biomanufacturing strategies employed in developing 3D in vitro OS models, highlighting their role in replicating different aspects of OS and improving OS anticancer research and drug screening. A variety of 3D in vitro models are explored, including both scaffold‐free and scaffold‐based models, encompassing cell spheroids, hydrogels, and innovative approaches like electrospun nanofibers, microfluidic devices and bioprinted constructs. By examining the distinctive features of each model type, this review offers insights into their potential transformative impact on the landscape of OS research and therapeutic innovation, addressing the challenges and future directions of 3D in vitro OS modeling.

Comparison of Echo Planar and Turbo Spin Echo Diffusion-Weighted Imaging in Intraoperative MRI.

Diffusion-weighted imaging (DWI) is routinely used in brain tumor surgery guided by intraoperative MRI (IoMRI). However, conventional echo planar imaging DWI (EPI-DWI) is susceptible to distortion and artifacts that affect image quality. Turbo spin echo DWI (TSE-DWI) is an alternative technique with minimal spatial distortions that has the potential to be the radiologically preferred sequence. To compare via single- and multisequence assessment EPI-DWI and TSE-DWI in the IoMRI setting to determine whether there is a radiological preference for either sequence. Retrospective. Thirty-four patients (22 female) aged 2-61 years (24 under 18 years) undergoing IoMRI during surgical resection of intracranial tumors. 3-T, EPI-DWI, and TSE-DWI. Patients were scanned with EPI- and TSE-DWI as part of the standard IoMRI scanning protocol. A single-sequence assessment of spatial distortion and image artifact was performed by three neuroradiologists blinded to the sequence type. Images were scored regarding distortion and artifacts, around and remote to the resection cavity. A multisequence radiological assessment was performed by three neuroradiologists in full radiological context including all other IoMRI sequences from each case. The DWI images were directly compared with scorings of the radiologists on which they preferred with respect to anatomy, abnormality, artifact, and overall preference. Wilcoxon signed-rank tests for single-sequence assessment, weighted kappa for single and multisequence assessment. A P-value <0.001 was considered statistically significant. For the blinded single-sequence assessment, the TSE-DWI sequence was scored equal to or superior to the EPI-DWI sequence for distortion and artifacts, around and remote to the resection cavity for every case. In the multisequence assessment, all radiologists independently expressed a preference for TSE-DWI over EPI-DWI sequences on viewing brain anatomy, abnormalities, and artifacts. The TSE-DWI sequences may be favored over EPI-DWI for IoMRI in patients with intracranial tumors. 2 TECHNICAL EFFICACY: Stage 5.

Tumor Resection in Hepatic Carcinomas Restores Circulating T Regulatory Cells.

Background/Objectives: Cholangiocarcinoma (CCA) and hepatocellular carcinoma (HCC) represent major primary liver cancers, affecting one of the most vital organs in the human body. T regulatory (Treg) cells play an important role in liver cancers through the immunosuppression of antitumor immune responses. The current study focuses on the characterization of circulating natural killer (NK) cells and T cell subsets, including Treg cells, in CCA and HCC patients, before and after surgical tumor resection, in order to understand the effect of tumor resection on the homeostasis of peripheral blood NK cells and T cells. Methods: Whole blood assays were performed to monitor immune alterations and the functional competence of circulating lymphocytes in a group of ten healthy individuals, eight CCA patients, and twenty HCC patients, before and one month after the surgical procedure, using flow cytometry, cell sorting, and qRT-PCR. Results: Before tumor resection, both HCC and CCA patients display increased percentages of CD8+ Treg cells and decreased frequencies of circulating CD4+ Treg cells. Notwithstanding, no functional impairment was detected on circulating CD4+ Treg cells, neither in CCA nor in HCC patients. Interestingly, the frequency of peripheral CD4+ Treg cells increased from 0.55% ± 0.49 and 0.71% ± 0.54 (in CCA and HCC, respectively) at T0 to 0.99% ± 0.91 and 1.17% ± 0.33 (in CCA and HCC, respectively) at T1, following tumor resection. Conclusions: Our results suggest mechanisms of immune modulation induced by tumor resection.

Evaluation of prognostic factors for late recurrence in clear cell renal carcinoma: an institutional study.

Following nephrectomy with curative intent, a subset of patients diagnosed with non-metastatic renal cell carcinoma (nmRCC) will present late recurrences, with metastatic relapses after 5 years from the surgical intervention. The aim of this study is to evaluate the prevalence of late recurrences in Romanian patients with nmRCC that have undergone surgery and to assess the clinicopathological characteristics prognostic for late-relapse RCC. This is a single-center, retrospective and observational study that analyzed patients with nmRCC with clear cell histology who underwent surgical resection of the primary tumor with curative intent. The patients included in the study were treated and further surveilled according to a personalized follow-up plan between January 2011 and December 2012 in The Oncology Institute "Prof. Dr. Ion Chiricuţă", Cluj-Napoca, Romania. Study endpoints included median disease-free survival (DFS), median overall survival (OS), as well as evaluation of possible prognostic factors indicative of late relapse. In the study cohort (n=51), the median DFS was 46 months and median OS was 130 months. DFS was significantly correlated with the International Metastatic Renal Cell Carcinoma Database Consortium (IMDC) score (p=0.04, HR=2.48; 95% CI [1.02, 6.01]), neutrophil to lymphocyte ratio (NLR) (a higher NLR value was associated with a poorer DFS, p=0.035), tumor size (T4 tumors vs. T1 p<0.05, HR=9,81; 95% CI [2.65, 36.27]) and Fuhrman nuclear grade (Fuhrman grade 1 vs. Fuhrman grade 3 p<0.05, HR=4,16; 95% CI = [1.13,15.22]). Fifty one percent of the patients included experienced disease relapse. From this subgroup, a significant percentage of 42% patients presented disease recurrence after 60 months from nephrectomy. OS was correlated to IMDC score (p=0.049, HR=2.36; 95% CI [1, 5.58]) and Fuhrman nuclear grade (Fuhrman grade 1 vs. Fuhrman grade 3 p<0.05, HR=3,97; 95% CI [1.08, 14.54]). The results of this study support the previously presented biological behavior of RCC, demonstrating that late recurrences in RCC are not uncommon occurrences and patients with localized RCC should be followed up for a longer interval after the surgery for the primary tumor. In addition, the study strengthens the data supporting certain biomarkers as valuable prognostic factors determining survival outcomes of patients with RCC.

8537 Refractory Hypoglycemia Secondary To Metastatic Insulinoma Treated With Novel Insulin Receptor Antibody - A Case Report

Abstract Disclosure: J. Lloyd: None. S. Abu Omar: None. L. Lester: None. L. Wilson: None. Introduction: Insulinoma is the most common functional pancreatic neuroendocrine tumor, characterized by hypersecretion of insulin, causing hypoglycemia. Insulinomas are mostly benign, however malignant neoplasms account for 5-10 % of cases. Surgical resection is the preferred treatment for solitary tumor, however metastatic insulinoma requires a more aggressive approach with medications to prevent hypoglycemia, resection of primary tumor, resection of metastasis, and chemoembolization. We describe a case of metastatic insulinoma with refractory hypoglycemia despite treatment with multiple medications, surgical resection of tumor, embolization of liver metastasis and successfully treated with a novel monoclonal antibody that blocks insulin receptor. Clinical Case: 43-year-old female was initially diagnosed with metastatic insulinoma in 2021. The primary tumor was pancreatic with metastasis to the liver. She was treated with surgical resection of the primary tumor and three hepatic embolizations for liver metastasis. She required a progressive number of medications to treat frequent, debilitating hypoglycemia. These medications included diazoxide, verapamil, lanreotide then changed to pasireotide, everolimus, and dexamethasone. Despite these treatments, she experienced refractory hypoglycemia and was admitted to the hospital. She required continuous dextrose infusion up to 100ml/hr of D50. Due to the large volume of fluid from dextrose infusion and other medications, she developed severe edema and AKI and required aggressive diuretic regimens and briefly intermittent CRRT. As there were no additional medications to add and prospects for future liver embolization were limited, we requested use of RZ358 through the manufacturer’s Expanded Patient Access program. This medication is a monoclonal antibody that blocks the insulin receptor to counteract the effects of insulin and thereby reduce hypoglycemia. This mechanism of action is unique from medications used to manage insulinoma induced hypoglycemia. She received her first infusion of RZ358 which she tolerated well. She had baseline elevation of ALP due to liver metastasis with further rise after liver embolizations, most recently 4 weeks prior. There was a rise in ALP levels which stabilized after 3 days. She experienced no significant side effects. For the first time in two months, five days after her first infusion of RZ358, the dextrose infusion could be stopped. She received her second infusion of RZ358 one week after first infusion. She was discharged home in a stable condition shortly after the second infusion. Conclusion: The Insulin receptor blocking monoclonal antibody, RZ358, offers a promising approach to patients with metastatic insulinoma who have refractory hypoglycemia despite maximal medical and surgical therapy. Presentation: 6/1/2024

8282 A Diagnostically Challenging Case of Ectopic ACTH Secreting Pancreatic Neuroendocrine Tumor Presenting with Cushing’s Syndrome

Abstract Disclosure: O.A. Aluko: None. S. Patel: None. S.V. Silparshetty: None. T. Gallagher: None. Introduction: Ectopic ACTH mediated Cushing’s syndrome is an uncommon but treatable condition that poses time constrained diagnostic and therapeutic challenge due to severe morbidity as illustrated by our case below. Clinical case:A 65-year-old male was admitted with profound generalized weakness. He became restricted to wheelchair from being able to hike a trail at Yosemite national park 8 weeks prior. Recent history included hospitalization with uncontrolled diabetes and hypertension, new vertebral compression fractures, AKI, hypokalemia, proximal myopathy, anasarca, upper GI bleed and acute upper extremity DVT. Initial testing there revealed hypercortisolemia, elevated ACTH and a normal pituitary MRI. Further workup at our center revealed elevated 24hr urinary cortisol 2598 (n = 5 - 64 μg/24hr), random cortisol 55 (n= 4.2 -22.4 μg/dL) with elevated ACTH 194 (n= 7.2 - 63.3 pg/mL) consistent with ACTH dependent hypercortisolism. IPSS deferred due to AKI, underlying comorbidities and severe cervical stenosis with myelopathy. ACTH and cortisol remained elevated with an 8mg dexamethasone suppression test suggesting ectopic source ACTH. CT with contrast of chest, abdomen and pelvis showed 5mm right lower lobe lung nodule and bilateral adrenal nodularity. Bronchoscopic FNAC was negative for NET.Ketoconazole 400 mg twice daily was started pending localization of culprit lesion with improvement in 24 hr urinary cortisol to 554μg/24 hr however this was stopped within 4 weeks due to acute transaminasemia. Repeat imaging with Gallium-68 dotatate PET CT showed a 1.8 X 2.4 X 1.7 cm pancreatic mass. He underwent distal pancreatectomy with splenectomy. Pathology confirmed a 2.2cm well differentiated neuroendocrine tumor limited to the pancreas with immunohistochemistry strongly for ACTH and weakly for Gastrin. Postoperatively, patient was given hydrocortisone replacement. ACTH was 14.3 pg/mL and cortisol 6.2μg/dL a few weeks later. His diabetes, hypertension, hypokalemia, transaminasemia and proximal myopathy improved. Discussion:Ectopic ACTH mediated Cushing’s syndrome is responsible for about 5 - 20% of all Cushing’s syndrome cases. Pancreatic neuroendocrine tumor secreting Ectopic ACTH is rarer but can be aggressive. Clinical presentation can be confounding due to secretion of &amp;gt;1 neurohormone i.e ACTH and Gastrin in our patient. Gallium-DOTATATE PET/CT tracer has a very high sensitivity and specificity. Early use of this imaging may prevent comorbidity and mortality as surgical resection of ectopic ACTH secreting neuroendocrine tumor is first line therapy. Other diagnostic principles to consider are that severely elevated ACTH levels correlate only with a pituitary macroadenoma, IPSS is invasive and has relative contraindication in sick patients and Desmopressin stimulation test is not widely available. Presentation: 6/1/2024

6702 Management And Complications Of Metastatic Adrenocortical Carcinoma Presenting With Severe Cushing Syndrome

Abstract Disclosure: S. Rodrigues: None. A.K. Sumal: None. Background: Metastatic adrenocortical carcinoma (ACC) presenting with Cushing syndrome (CS) is a complicated, aggressive disease that commonly requires multiple adrenal steroidogenesis inhibitors and chemotherapy to achieve hormonal and tumor control. Clinical Case: A 66-year-old man with a history of prostate cancer and hypertension presented with right flank and back pain, worsening type 2 diabetes, profound proximal muscle weakness, and 3+ lower extremity edema to his thighs. CT and PET-CT revealed a 10.9 cm right adrenal mass with pericaval lymphadenopathy and metastatic disease at the L2 vertebral body. Laboratory testing demonstrated evidence of hypercortisolism with elevated 24-hour urinary cortisol excretion (449 mcg/24h; n&amp;lt;45 mcg/24h), and abnormal 1 mg dexamethasone suppression test (cortisol 15 mcg/dL; n&amp;lt; 1.8 mcg/dL) with suppressed ACTH (&amp;lt;6 pg/mL; n=7-63 pg/mL). Surgical resection of the primary tumor was aborted intraoperatively given the discovery of new peritoneal metastases, which were confirmed by biopsy to be metastatic ACC. He was started on mitotane and osilodrostat to manage his severe CS. He was also started on dexamethasone, both to prevent adrenal insufficiency and to avoid influencing serum cortisol measurements used to assess disease control. However, given his significant peripheral edema and weakness, he was functionally unable to receive chemotherapy. Despite rapid uptitration of mitotane and osilodrostat over three weeks, his CS remained uncontrolled, and he was ultimately hospitalized for lower extremity paralysis and septic shock due to pyelonephritis. Repeat imaging revealed severe spinal canal stenosis from an L2 pathologic fracture, as well as worsening hepatic, osseous, peritoneal, and retroperitoneal metastases. After recovery from his septic shock, he was started on chemotherapy with carboplatin and etoposide while hospitalized, but his mitotane was intermittently held due to elevated transaminases. His hospital course was complicated by hypotension requiring pressor support, atrial fibrillation, hemoperitoneum, worsening anasarca, and acute kidney injury requiring continuous renal replacement therapy. Given his worsening condition that precluded him from further chemotherapy or palliative radiation, he elected to pursue comfort care measures and expired shortly thereafter. Conclusion: This case highlights the therapeutic challenges of metastatic ACC presenting with life-threatening CS. Simultaneous use of multiple adrenal steroidogenesis inhibitors is often required for control of hypercortisolism, and chemotherapy is equally necessary to manage tumor burden. However, as in this case, disease-related complications can limit treatment management and result in rapid deterioration. Thus, early diagnosis and prompt treatment of metastatic ACC presenting with CS is critical to prevent morbidity and mortality. Presentation: 6/3/2024