Small Tumors Research Articles

The prognosis of patients with locally advanced cervical cancer undergoing surgical versus non-surgical treatment: A retrospective cohort study based on SEER database and a single-center data.

The aim of this study was to investigate the impact of surgical treatment on the survival prognosis of patients with locally advanced cervical cancer (LACC) and to identify factors that may influence the efficacy of surgery. Data from the SEER database (2000-2020) and a hospital (2013-2023) were collected for this investigation. Utilizing multivariable Cox regression analysis, Kaplan-Meier survival analysis, and log-rank tests, we assessed the effects of surgical intervention on overall survival (OS) and disease-specific survival (DSS) in LACC patients. Our results revealed that in the SEER database, the surgical group exhibited significantly better OS and DSS compared to the non-surgical group. Particularly noteworthy was the significantly higher survival rate in the surgical group for patients with tumor diameters less than 6 cm. Furthermore, both OS and DSS were improved in the surgical group regardless of whether the cancer was squamous cell carcinoma or adenocarcinoma. Additionally, patients who underwent surgery combined with radiotherapy had notably better OS and DSS compared to those who received chemoradiotherapy alone. Similarly, our hospital data showed that the surgical group demonstrated significantly better OS than the non-surgical group, especially for patients with tumors smaller than 6 cm in diameter. These findings suggest that surgery combined with radiotherapy may offer more favorable outcomes than chemoradiotherapy alone, particularly for LACC patients with smaller tumors.

Treatment strategies with electrochemotherapy for limb in-transit melanoma: Real-world outcomes from a European, retrospective, cohort study

BackgroundThis study analysed treatment strategies with electrochemotherapy (ECT) in melanoma with limb in-transit metastases (ITM). MethodsWe audited AJCC v.8 stage IIIB-IIID patients treated across 22 centres (2006–2020) within the International Network for Sharing Practices of ECT (InspECT). Results452 patients were included, 58 % pre-treated (93 % had lower limb ITM, 44 % had ≤10 metastases [median size 1.5 cm]. Treatment strategies included first-line ECT (n = 145, 32 %), ECT with concurrent locoregional/systemic treatment (n = 163, 36 %), and salvage ECT (n = 144, 32 %). The objective response rate was 63 % (complete response [CR], 24 %), increasing to 74 % (CR, 39 %) following retreatment (median two ECT, range 1–8). CR rate in treatment-naïve and pre-treated patients was 50 % vs 32 % (p < 0.001). Bleomycin de-escalation was associated with lower CR (p = 0.004). Small tumour number and size, hexagonal electrode, retreatment, and post-ECT skin ulceration predicted response in multivariable analysis. At a median follow-up of 61 months, local and locoregional recurrence occurred in 55 % and 81 % of patients. Median local progression-free, new lesions-free, and regional recurrence-free survival were 32.9, 6.9, and 7.7 months. Grade-3 toxicity was 15 %. Concurrent treatment and CR correlated with improved regional control and survival. Concomitant checkpoint inhibition did not impact toxicity or survival outcomes. The median overall survival was 5.7 years. ConclusionsAmong patients with low-burden limb-only ITM, standard-dose bleomycin ECT results in durable local response. Treatment naivety, low tumour volume, hexagonal electrode application, retreatment, and post-ECT ulceration predict response. CR and concurrent treatment correlate with improved regional control and survival outcomes. Combination with checkpoint inhibitors is safe but lacks conclusive support.

Predictors of Durable Remission After Successful Surgery for Cushing Disease: Results From the Multicenter RAPID Registry.

Cushing disease (CD) affects mortality and quality of life along with limited long-term remission, underscoring the need to better identify recurrence risk. The identification of surgical or imaging predictors for CD remission after transsphenoidal surgery has yielded some inconsistent results and has been limited by single-center, single-surgeon, or meta-analyses studies. We sought to evaluate the multicenter Registry of Adenomas of the Pituitary and Related Disorders (RAPID) database of academic US pituitary centers to assess whether robust nonhormonal recurrence predictors could be elucidated. Patients with treated CD from 2011 to 2023 were included. The perioperative and long-term characteristics of CD patients with and without recurrence were assessed using univariable and multivariable analyses. Of 383 patients with CD from 26 surgeons achieving postoperative remission, 288 (75.2%) maintained remission at last follow-up while 95 (24.8%) showed recurrence (median time to recurrence 9.99 ± 1.34 years). Patients with recurrence required longer postoperative hospital stays (5 ± 3 vs 4 ± 2 days, P = .002), had larger average tumor volumes (1.76 ± 2.53 cm 3 vs 0.49 ± 1.17 cm 3 , P = .0001), and more often previously failed prior treatment (31.1% vs 14.9%, P = .001) mostly being prior surgery. Multivariable hazard prediction models for tumor recurrence found younger age (odds ratio [OR] = 0.95, P = .002) and Knosp grade of 0 (OR = 0.09, reference Knosp grade 4, P = .03) to be protective against recurrence. Comparison of Knosp grade 0 to 2 vs 3 to 4 showed that lower grades had reduced risk of recurrence (OR = 0.27, P = .04). Other factors such as length of stay, surgeon experience, prior tumor treatment, and Knosp grades 1, 2, or 3 failed to reach levels of statistical significance in multivariable analysis. This multicenter study centers suggests that the strongest predictors of recurrence include tumor size/invasion and age. This insight can help with patient counseling and prognostication. Long-term follow-up is necessary for patients, and early treatment of small tumors may improve outcomes.

Cryotherapy in the Treatment of Early-Stage Breast Cancer.

Breast cancer is one of the most common malignancies, affecting millions of people worldwide annually. The treatment paradigm for early-stage breast cancer is in flux. The focus is now on opportunities to de-escalation treatment to minimize morbidity and maximize patients' quality of life. Recently, percutaneous minimally invasive ablative techniques have been explored. Early trials in small population of patients demonstrated cryoablation to be effective, safe, and well-tolerated in an outpatient setting. Subsequent surgical resection was performed and the ablation success rate was the highest if the tumor was less than 1.5 cm and with < 25% ductal carcinoma in situ component. ACOSOG Alliance Z1072, a phase II trial with curative intent, demonstrated 100% ablation in all tumors smaller than 1 cm and 92% success in lesions without multifocal disease and less than 2 cm in size. There are ongoing prospective clinical trials to investigate the efficacy of cryoablation without surgical excision for treatment of early-stage breast cancer. FROST (Freezing Instead of Removal Of Small Tumors) started in 2016 is ongoing, ICE3 (Cryoablation of Low Risk Small Breast Cancer) started in 2014 just released 5 years results, and COOL-IT: Cryoablation vs Lumpectomy in T1 Breast Cancers is also ongoing. These prospective trials will expand our knowledge on the safety and value of cryoablation. It is crucial to understand the indications, technical nuances, and distinctive imaging findings for cryoablation as it has potential to revolutionize standard surgical practice.

Investigating causal links between gallstones, cholecystectomy, and 33 site-specific cancers: a Mendelian randomization post-meta-analysis study

Background and aimThe association between gallstones/cholecystectomy and cancer remains inconclusive in the current literature. This study aimed to explore the causal connections between gallstones/cholecystectomy and cancer risk by utilizing a bidirectional two-sample multivariable Mendelian randomization approach with Genome-Wide Association Studies data.MethodsUtilizing Genome-Wide Association Studies data from the UK Biobank and FinnGen, this research employed multivariable Mendelian randomization analyses to explore the impact of gallstones and cholecystectomy on the risk of 33 distinct cancer types. Instrumental variables for gallstones and cholecystectomy were carefully selected to ensure robust analyses, and sensitivity and heterogeneity tests were conducted to verify the findings’ validity.ResultsMultivariable Mendelian randomization analysis, incorporating data from more than 450,000 individuals for gallstones and cholecystectomy, revealed nuanced associations with cancer risk. Cholecystectomy was associated with a significantly increased risk of nonmelanoma skin cancer (OR = 1.59, 95% CI: 1.21 to 2.10, P = 0.001), while gallstones were linked to a decreased risk of the same cancer type (OR = 0.63, 95% CI: 0.47 to 0.84, P = 0.002). Interestingly, the analysis also suggested that cholecystectomy may lower the risk of small intestine tumors (OR = 0.18, 95% CI: 0.043 to 0.71, P = 0.015), with gallstones showing an inverse relationship, indicating an increased risk (OR = 6.41, 95% CI: 1.48 to 27.80, P = 0.013).ConclusionsThe multivariable Mendelian randomization analysis highlights the differential impact of gallstones and cholecystectomy on cancer risk, specifically for nonmelanoma skin cancer and small intestine tumors. These results underscore the importance of nuanced clinical management strategies and further research to understand the underlying mechanisms and potential clinical implications of gallstone disease and cholecystectomy on cancer risk.

A deep learning-informed interpretation of why and when dose metrics outside the PTV can affect the risk of distant metastasis in SBRT NSCLC patients

PurposeRecent papers suggested a correlation between the risk of distant metastasis (DM) and dose outside the PTV, though conclusions in different publications conflicted. This study resolves these conflicts and provides a compelling explanation of prognostic factors.Materials and methodsA dataset of 478 NSCLC patients treated with SBRT (IMRT or VMAT) was analyzed. We developed a deep learning model for DM prediction and explainable AI was used to identify the most significant prognostic factors. Subsequently, the prognostic power of the extracted features and clinical details were analyzed using conventional statistical methods.ResultsTreatment technique, tumor features, and dosiomic features in a 3 cm wide ring around the PTV (PTV3cm) were identified as the strongest predictors of DM. The Hazard Ratio (HR) for Dmean,PTV3cm was significantly above 1 (p < 0.001). There was no significance of the PTV3cm dose after treatment technique stratification. However, the dose in PTV3cm was found to be a highly significant DM predictor (HR > 1, p = 0.004) when analyzing only VMAT patients with small and spherical tumors (i.e., sphericity > 0.5).ConclusionsThe main reason for conflicting conclusions in previous papers was inconsistent datasets and insufficient consideration of confounding variables. No causal correlation between the risk of DM and dose outside the PTV was found. However, the mean dose to PTV3cm can be a significant predictor of DM in small spherical targets treated with VMAT, which might clinically imply considering larger PTV margins for smaller, more spherical tumors (e.g., if IGTV > 2 cm, then margin ≤ 7 mm, else margin > 7 mm).

Type and dimensions can predict ventricular arrhythmias and cardiac death in primary benign cardiac tumors in children

Despite being extremely rare in children, primary benign cardiac tumors can cause malignant ventricular arrhythmias (VA) or even sudden cardiac death. To assess the predictors of cardiovascular death and malignant VAs, we designed a retrospective single-center study enrolling paediatric patients. We defined as primary outcome a composite of cardiovascular death, sustained VT, ventricular fibrillation and rapid, symptomatic non-sustained VT. Our secondary endpoint was to assess the prevalence of clinically significant arrhythmias in our population. Methods and resultsWe fitted a multivariate Cox regression model to assess the predictors of the primary outcome. Over a period of 38 years, a total of 97 children were enrolled in the study. Among them, there were 73 rhabdomyomas, 13 fibromas, 3 myxomas, 3 teratomas, 1 lipoma, 2 haemangiomas and 2 fibroelastomas. Over a median follow up of 10.53 years, 16 patients met the primary outcome. Kaplan Meier unadjusted survival estimates showed that tumor dimensions larger than 2.3 cm and diagnosis of fibroma predicted worse outcomes compared with smaller tumors or other histotypes, (log rank p < 0.0002 and < 0.0001 respectively). In multivariate Cox proportional hazards analysis, diagnosis of fibroma and tumor dimensions were independently associated to the primary endpoint (HR: 5.06, 95 %CI (1.3–19); and 1.26 • (1.05–11), respectively). Clinically significant arrhythmias were reported in 24.5 % of the study population. ConclusionsAmong paediatric primary cardiac tumors, type and dimensions may predict the hazard of malignant VAs and cardiac death.

Computed tomography radiomics models of tumor differentiation in canine small intestinal tumors.

Radiomics models have been widely exploited in oncology for the investigation of tumor classification, as well as for predicting tumor response to treatment and genomic sequence; however, their performance in veterinary gastrointestinal tumors remains unexplored. Here, we sought to investigate and compare the performance of radiomics models in various settings for differentiating among canine small intestinal adenocarcinoma, lymphoma, and spindle cell sarcoma. Forty-two small intestinal tumors were contoured using four different segmentation methods: pre- or post-contrast, each with or without the inclusion of intraluminal gas. The mesenteric lymph nodes of pre- and post-contrast images were also contoured. The bin settings included bin count and bin width of 16, 32, 64, 128, and 256. Multinomial logistic regression, random forest, and support vector machine models were used to construct radiomics models. Using features from both primary tumors and lymph nodes showed significantly better performance than modeling using only the radiomics features of primary tumors, which indicated that the inclusion of mesenteric lymph nodes aids model performance. The support vector machine model exhibited significantly superior performance compared with the multinomial logistic regression and random forest models. Combining radiologic findings with radiomics features improved performance compared to using only radiomics features, highlighting the importance of radiologic findings in model building. A support vector machine model consisting of radiologic findings, primary tumors, and lymph node radiomics features with bin count 16 in post-contrast images with the exclusion of intraluminal gas showed the best performance among the various models tested. In conclusion, this study suggests that mesenteric lymph node segmentation and radiological findings should be integrated to build a potent radiomics model capable of differentiating among small intestinal tumors.

Adenoid basal carcinoma cervix – A rare epithelial neoplasm

ABSTRACT Adenoid basal carcinoma of the uterine cervix is a rare epithelial neoplasm. Adenoid basal carcinoma constitutes less than 1% of all cervical adenocarcinomas and has a favorable prognosis. Adenoid basal carcinoma is assumed to arise from a multipotential basal or reserve cell layer in the cervical epithelium. We report a case of adenoid basal carcinoma of the uterine cervix with complaints of bleeding per vagina in a 40-year-old female. The carbohydrate antigen 125 level was elevated (100 U/ml), and the MRI abdomen and pelvis revealed increased signal intensity in the anterior lip of the cervix. The local examination revealed thickening of the anterior lip of the cervix and induration in the left fornix. The patient was diagnosed with carcinoma cervix stage IB2 (FIGO Stage). The patient was operated by a radical robotic hysterectomy. Microscopic examination revealed small basaloid tumor cell nests with peripheral cell palisading and microcyst formation. The tumor cells showed p63 immunoreactivity in basaloid tumor cells and were negative for CD117 and S-100P. This tumor should be differentiated from adenoid basal cell hyperplasia, which has a favorable outcome, and adenoid cystic carcinoma, with a dismal course.

ASO Visual Abstract: Patterns of Care and Outcomes for Patients With Small Gastrointestinal Stromal Tumors at a High-Volume Sarcoma Center

ASO Visual Abstract: Patterns of Care and Outcomes for Patients With Small Gastrointestinal Stromal Tumors at a High-Volume Sarcoma Center

Phosphaturic mesenchymal tumor demonstrated by 68Ga-DOTATATE PET/CT in a patient: a case report

Tumor-induced osteomalacia (TIO) is a paraneoplastic syndrome caused by abnormally high levels of fibroblast growth factor 23 (FGF-23), most commonly produced and secreted by small phosphaturic mesenchymal tumors (PMT). These tumors can show various anatomic locations throughout soft tissue and bone. The presence of the tumor itself rarely causes symptoms. Nonspecific symptoms such as muscle weakness and musculoskeletal pain are related to the developing hypophosphatemia and osteomalacia as a secondary effect of the increased circulating levels of FGF-23. Therefore, as the initial presentation can mimic a wide range of metabolic or inflammatory diseases, proper diagnosis is often delayed. Localization of the tumor is crucial, as its complete surgical resection is the only curative treatment. Whole-body functional imaging targeting the overexpression of somatostatin receptors (SSTR) on the surface of the PMT cells, is a highly specific and sensitive imaging method to detect the primary tumor site. Here, we discuss a case of TIO in a patient initially presenting with symptoms of inflammatory spondyloarthritis. SSTR positron emission imaging using 68Ga-DOTATATE was central in diagnosing and localizing the primary tumor.

Food antigens suppress small intestinal tumorigenesis.

Food components suppressing small intestinal tumorigenesis are not well-defined partly because of the rarity of this tumor type compared to colorectal tumors. Using Apcmin/+ mice, a mouse model for intestinal tumorigenesis, and antigen-free diet, we report here that food antigens serve this function in the small intestine. By depleting Peyer's patches (PPs), immune inductive sites in the small intestine, we found that PPs have a role in the suppression of small intestinal tumors and are important for the induction of small intestinal T cells by food antigens. On the follicle-associated epithelium (FAE) of PPs, microfold (M) cells pass food antigens from lumen to the dendritic cells to induce T cells. Single-cell RNA-seq (scRNA-seq) analysis of immune cells in PPs revealed a significant impact of food antigens on the induction of the PP T cells and the antigen presentation capacity of dendritic cells. These data demonstrate the role of food antigens in the suppression of small intestinal tumorigenesis by PP-mediated immune cell induction.

Exosomal fragment enclosed polyamine-salt nano-complex for co-delivery of docetaxel and mir-34a exhibits higher cytotoxicity and apoptosis in breast cancer cells

A novel core–shell nanocarrier system has been designed for co-delivery of a small anticancer drug, docetaxel (DTX) and tumor suppressor (TS) miR-34a named as Exo(PAN34a+DTX). The core is formed by pH dependent polyamine salt aggregates (PSA) containing both the payloads and the shell is formed by RAW 264.7 cell derived exosomal fragments. Herein, phosphate driven polyallylamine hydrochloride (PAH, MW:17,500 Da) PSA was formed in presence of miR-34a and DTX to form PAN34a+DTX. The formulation exhibited pH dependent DTX release with only 33.55 ± 2.12% DTX release at pH 7.2 and 75.21 ± 1.8% DTX release till 144 h at pH 5.5. At 1.21 molar ratio of phosphate to the amine (known as R value), efficient complexation of miR-34a (3.6 μM) in the PAN particles was obtained. PAN34a+DTX demonstrated particle size (163.86 ± 12.89 nm) and zeta-potential value of 17.53 ± 5.10 mV which upon exosomal fragment layering changed to − 7.23 ± 2.75 mV which is similar to the zeta-potential of the exosomal fragments, i.e., − 8.40 ± 1.79 mV. The final formulation Exo(PAN34a+DTX), loaded with 40 ng/mL DTX and 50 nM miR-34a exhibited 48.20 ± 4.59% cytotoxicity in triple negative breast cancer (TNBC) cells, 4T1. Co-localization of CM-DiI (red fluorescence) stained exosomal fragments and FAM-siRNA (green fluorescence) in the cytoplasm of 4T1 cells after 6 h of Exo(PANFAM) treatment confirmed the efficiency of the designed system to co-deliver two actives. Exo(PAN34a+DTX) also reduced BCL-2 expression (target gene for miR-34a) by 8.98 folds in comparison to free DTX confirming promising co-delivery and apoptosis inducing effect of Exo(PAN34a+DTX) in 4T1.

Small bowel neuroendocrine tumors: Unique features and low lethality compared with small bowel adenocarcinoma.

Population-based studies comparing clinical characteristics and survival disparities between patients with small bowel adenocarcinoma (SBA) and small bowel neuroendocrine tumors (SBNETs) in the United States are limited. Data for patients with SBA or SBNETs, obtained from the Surveillance, Epidemiology, and End Results database for the years between 2000 and 2018 were analyzed. Between 2000 and 2018, the age-adjusted incidence of SBA experienced a marginal increase whereas SBNETs demonstrated a significant increase, emerging as the predominant subtype of small bowel cancer (SBC). Diagnoses peaked at ages 65-69years for SBA and 60-64years for SBNETs, with the latter exhibiting a heightened age-specific incidence and maintaining equilibrium in gender distribution. Clinicopathologic disparities revealed SBA's duodenal predilection, larger tumor size, and advanced stages, contrasting with SBNETs' ileal predilection, early-stage presentation, and superior outcomes. SBNETs patients underwent surgery more frequently but received less chemotherapy and radiation than SBA patients. Factors intricately correlated with a diagnosis of SBNETs included female gender, White race, advanced age, marital status, recent diagnoses, superior tumor differentiation, smaller size, distal location, and early-stage presentation. Survival analysis unveiled a remarkable 79% reduction in the mortality risk for SBNETs compared with SBA. Subgroup analysis further confirmed the consistently favorable survival advantages of SBNETs, highlighting the clinical relevance of histological classification in prognostication. Compared with SBA, SBNETs exhibited distinctive clinicopathological features characterized by a higher inclination toward low-grade and early-stage manifestations, thereby contributing to superior survival outcomes.

Device-Less Data-Driven Cardiac and Respiratory Gating Using LAFOV PET Histo Images.

Background: The outstanding capabilities of modern Positron Emission Tomography (PET) to highlight small tumor lesions and provide pathological function assessment are at peril from image quality degradation caused by respiratory and cardiac motion. However, the advent of the long axial field-of-view (LAFOV) scanners with increased sensitivity, alongside the precise time-of-flight (TOF) of modern PET systems, enables the acquisition of ultrafast time resolution images, which can be used for estimating and correcting the cyclic motion. Methods: 0.25 s so-called [18F]FDG PET histo image series were generated in the scope of for detecting respiratory and cardiac frequency estimates applicable for performing device-less data-driven gated image reconstructions. The frequencies of the cardiac and respiratory motion were estimated for 18 patients using Short Time Fourier Transform (STFT) with 20 s and 30 s window segments, respectively. Results: The Fourier analysis provided time points usable as input to the gated reconstruction based on eight equally spaced time gates. The cardiac investigations showed estimates in accordance with the measured pulse oximeter references (p = 0.97) and a mean absolute difference of 0.4 ± 0.3 beats per minute (bpm). The respiratory frequencies were within the expected range of 10-20 respirations per minute (rpm) in 16 out of 18 patients. Using this setup, the analysis of three patients with visible lung tumors showed an increase in tumor SUVmax and a decrease in tumor volume compared to the non-gated reconstructed image. Conclusions: The method can provide signals that were applicable for gated reconstruction of both cardiac and respiratory motion, providing a potential increased diagnostic accuracy.

Abstract B051: Influence of MUC16 on the immune tumor microenvironment of PDAC

Abstract Pancreatic ductal adenocarcinoma (PDAC) is an aggressive disease. In most cases, PDAC initiation results from oncogenic KRAS mutations, that act in part by directly increasing levels of a glycoprotein called Mucin-16 (MUC16). MUC16 is virtually absent in the normal pancreas, expressed on tumor cells in &amp;gt;65% of PDAC and is a marker of poor prognosis. The cell autonomous roles of MUC16 involve signaling through the ErbB-1/2/3 axes, and eliciting downstream AKT and GSK-3β activation to promote cell proliferation and survival. PDAC has a very interesting “immune cold” tumor microenvironment (TME) that is devoid of anti-tumor T cells and is instead flush with pro-tumor myeloid cells like macrophages. However, the role of MUC16 in influencing immune cells, particularly macrophages has not been investigated. Methods: We use immunohistochemistry to check for macrophage populations in spontaneous and orthotopic models of PDAC, KPC (LSL-Kras G12D/+ ; LSL-Trp53 R172H/+ ; Pdx-1- Cre) and a derived KPC-MUC16 knockout (KPC-M16KO). Orthotopic implantation with KPC and KPC-M16- cells was done to assess survival. In vitro cytokine screening from M16+/- cells was done to understand cytokine players in MUC16-mediated immunosuppression. Clodronate liposomes (CL) and neutral control liposomes (NL) were used to deplete macrophages in orthotopically implanted KPC and KPC-M16- tumor-bearing mice, and flow cytometry was conducted to profile macrophages and T cells in the pancreas and spleens at the experimental endpoint. Results: We show that KPC-M16KO tumors have decreased M2-like macrophages, and a modest increase in M1-like macrophages, leading to a high M1/M2 ratio suggesting reduced immune suppressed cells in the KPC-M16KO models. KPC-M16KO tumor-bearing mice showed longer survival compared to the KPC group. In addition, we detect low levels of CCL2 and Serpin-E1 in cell lines and tumor tissues from KPC-M16KO models suggesting that they could serve as potential regulators of macrophage infiltration and M2-like polarization downstream of MUC16. Siglec-E (murine homolog of human Siglec-7/9) was also downregulated in KPC-M16KO tumors, suggesting MUC16-Siglec mediated immunosuppression as another mechanism. CL administration (versus NL) resulted in significant macrophage depletion in the spleens of mice with KPC and KPC-M16KO tumors, however, such depletion was not robust in the pancreas. Immune profiling studies showed a high M1/M2 ratio in the spleen and pancreas of mice treated with CL, suggesting a tumor cell-macrophage crosstalk, that could mediate M2-like macrophage states in a macrophage-rich TME. Mice treated with CL have smaller tumors, and KPC-M16KO+CL group had the smallest tumors, indicative that dual disruption of MUC16 and macrophages lowers tumor burden. Conclusions: These results suggest that MUC16 plays a crucial role in modulating the tumor immune microenvironment by increasing the accumulation of immunosuppressive macrophages in PDAC. Citation Format: Christabelle Rajesh, Satish Sagar, Prakash Radhakrishnan. Influence of MUC16 on the immune tumor microenvironment of PDAC [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Pancreatic Cancer Research; 2024 Sep 15-18; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(17 Suppl_2):Abstract nr B051.

Abstract C011: Targeting STAT3 overcomes PDAC resistance to EGFR/RAF1 inhibition leading to complete and durable tumor regression

Abstract Pancreatic ductal adenocarcinoma (PDAC) belongs to the tumors with worst prognosis due to the lack of effective treatment. It was previously demonstrated that combined elimination of EGFR and RAF1, two main mediators of the KRAS signaling, induces complete regression of a limited subset of small tumors in a genetically engineered mouse model (Blasco et al., 2019). In the current study, we show that resistance of PDACs with big sizes to the elimination of RAF1 and EGFR is mediated by STAT3. Indeed, combined genetic ablation of EGFR, RAF1 and STAT3 both in vitro and in vivo, results in complete and irreversible regression of more than 40 independent mouse PDAC tumors driven by Kras/Trp53 mutations. Importantly, all PDACs were characterized by increased initial tumor size and highly heterogeneous molecular profile similar to that of Basal human tumors. Moreover, we have validated the efficacy of this novel therapeutic strategy using pharmacological agents, such as EGFR inhibitors approved for clinical use and the STAT3 PROTAC degrader SD-36. Finally, inhibition of RAF1, EGFR and STAT3 expression effectively blocked in vitro and in vivo tumor progression in ten independent patient-derived organoid (PDO) and patient-derived xenograft (PDX) cultures carrying KRAS and TP53 mutations. These results open the door to the development of novel targeted therapies for PDAC patients. Citation Format: Vasiliki Liaki, Mariano Barbacid, Carmen Guerra. Targeting STAT3 overcomes PDAC resistance to EGFR/RAF1 inhibition leading to complete and durable tumor regression [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Pancreatic Cancer Research; 2024 Sep 15-18; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(17 Suppl_2):Abstract nr C011.

Incidence, survival, and prognostic nomogram of patients with small intestinal neuroendocrine tumors: A SEER population-based study.

Small intestinal neuroendocrine tumors (SI-NETs) are a group of rare and significantly heterogeneous tumors with limited research currently available. This study aimed to investigate the incidence, survival, and prognostic factors of SI-NETs. We selected data from the surveillance, epidemiology, and end results (SEER) database between 2000 and 2019 and evaluated the incidence trend of SI-NETs during this period. We utilized the Kaplan-Meier method to examine the association between clinical variables and survival rates. Based on the multivariable Cox regression analysis results, we developed a nomogram to predict the 1-, 2-, and 3-year cancer-specific survival (CSS) of SI-NETs patients. We evaluated the consistency, accuracy, and clinical utility of the nomogram by drawing calibration curves, receiver operating characteristic (ROC) curves, and decision curve analysis (DCA) curves. The incidence of SI-NETs showed an upward trend in recent years. Age, grade, T stage, M stage, and primary tumor surgery were independent risk factors for CSS in SI-NETs patients. The nomogram model based on these risk factors showed high accuracy and clinical benefit. SI-NETs are rare tumors with an increasing incidence rate. The nomogram model is expected to be an effective tool for personalized prognosis prediction in SI-NETs patients, which may benefit clinical decision-making.

TERT mutations and aggressive histopathologic characteristics of radioiodine-refractory papillary thyroid cancer.

Radioiodine (RI) ablation following thyroid-stimulating hormone suppression is an effective treatment for papillary thyroid cancer (PTC), typically leading to favorable outcomes. However, RI-refractory tumors exhibit aggressive behavior and poor prognoses. Recent studies highlight the role of genetic abnormalities in PTC signaling pathways, including the activation of telomerase reverse transcriptase (TERT), and the correlation of mutations with adverse outcomes. This study analyzed mutations in BRAF V600E and the TERT-promoter genes, comparing clinicopathological features between RI-refractory and RI-responsive PTCs. Among 82 RI-refractory patients, formalin-fixed, paraffin-embedded tissues from initial surgeries were available for 26. Another 89 without distant metastasis over 5 years formed a matched RI-responsive control group. Histopathologically, RI-refractory PTCs showed increased frequencies of small tumor clusters without fibrovascular cores, hobnail features, and a high height-to-width ratio of tumor cells. These tumors were more likely to exhibit necrosis, mitosis, lymph node metastasis, extrathyroidal extension, and involvement of resection margins. TERT-promoter mutations were statistically significantly associated with these aggressive clinicopathologic features. Immunohistochemically, decreased expression of sodium iodide symporter and thyroglobulin stimulating hormone receptor proteins was common in RI-refractory PTCs, along with lower levels of oncogenic proteins such as vascular endothelial cell growth factor, vascular endothelial cell growth factor receptor 2, and nuclear factor kappa-light-chain-enhancer of activated B cells. Total loss of PTEN expression was occasionally observed. In contrast, all cases tested positive for cytoplasmic β-catenin. RI-refractory PTCs are linked to TERT mutations and exhibit specific aggressive histopathologic features, particularly in tumor centers.

Experiences and Fundamental Care Needs in Patients With Small Intestinal Neuroendocrine Tumours-An Interview Study in a Surgical Context.

The study aimed to describe patients' fundamental care needs and their experiences of nursing care, throughout surgical treatment of small intestinal neuroendocrine tumours. A qualitative descriptive study was performed. Patients' interviews (n = 19) were conducted in Sweden from May 2021 to January 2022 and analysed using directed qualitative content analysis guided by the Fundamentals of Care framework. The results are presented in three descriptive categories chronologically throughout the care chain. In the preoperative phase of care, the category was 'Feeling safe but lonely and frightened, and struggling with existential thoughts'; experiences in the postoperative phase of care resulted in the category 'Feeling cared for but suffering from physical symptoms and feelings of loneliness'; and the category in the discharge phase was 'Lacking self-care information and feeling worried about the future'. There were deficiencies in the delivery of fundamental care for patients with a rare tumour diagnosis throughout surgical treatment. Nursing care is mostly task focused and fragmented, and there is a lack of psychosocial and relational care across the care chain. Registered nurses and nursing managers need to take responsibility for their leadership in nursing care to fulfil patients' fundamental care needs. The Fundamentals of Care framework could be used for work improvements to include all aspects of nursing care. High-quality nursing care is needed throughout the care chain, including self-care after discharge, for patients with this rare tumour diagnosis. A higher awareness of patients' experiences and the importance of psychosocial support is warranted. Registered nurses and nursing managers must revise and improve routines to support patients' psychosocial needs. Registered nurses need to take responsibility for their leadership in nursing care to fulfil patients' fundamental care needs. What problem did the study address? This study highlights patients' fundamental care needs and experiences of nursing care throughout surgical treatment of small intestinal neuroendocrine tumours. What were the main findings? There are deficiencies in fulfilling patients' fundamental care needs across the care chain and in all dimensions of the Fundamental of Care framework throughout surgical treatment of small intestinal neuroendocrine tumours. Patients struggled with loneliness and existential thoughts, as well as worries about the future. Patients experienced a lack of information about plans for the day, self-care, and follow-ups. Where and on whom will the research have an impact? For clinicians to develop an understanding of, and improve, fundamental care needs for patients with small intestinal neuroendocrine tumours in a surgical context. For registered nurses to understand the importance of their leadership and nursing responsibility to fulfil fundamental care needs. The consolidated criteria for reporting qualitative research (COREQ): a 32-item checklist for interviews and focus groups. The patients shared their experiences during the interviews, which has contributed to a deeper knowledge and understanding of the phenomena under study.