Type Of Primary Tumor Research Articles

Abstract B020: Understanding the role of dNTP pool on double-strand break and resistance to therapy in quiescent hypoxic glioblastoma

Abstract Glioblastoma (GBM) is the deadliest type of primary brain tumor. After surgical resection, chemotherapy, and radiotherapy (RT) are used as treatment modalities to induce double-strand breaks (DSBs), the most cytotoxic and lethal form of DNA damage. However, an inadequate oxygen supply and the high metabolic demand in rapidly growing solid tumors like GBM result in severe hypoxic regions contributing to altered cellular metabolism and resistance to these cancer therapies. These subpopulations of resistant and refractory hypoxic cancer cells are clinically significant as they lead to poor prognosis and adverse clinical outcomes in patients. Ionizing radiation (IR) and chemotherapeutics such as temozolomide induce DNA damage, such as base deletions, single-strand breaks (SSBs), and DSBs. Rapidly replicating cells are more sensitive to these therapeutic agents partly due to replication-induced conversion of SSB and other manageable damages to highly lethal DSB. A balanced deoxyribonucleoside triphosphate (dNTP) is crucial for DNA replication, repair, and maintenance of genomic stability. Cellular dNTP is mainly regulated by ribonucleotide reductase (RNR) and the SAM- and HD-domain-containing protein (SAMHD1). RNR boosts the cellular dNTP pool through the de novo synthesis while SAMHD1 depletes the pool by hydrolyzing dNTPs. Previous studies have shown that hypoxic cancer cells have low dNTP levels due to oxygen dependency of its rate limiting RNR enzyme, which could result in reduced DNA replication and cell cycle arrest. Here, we show the direct relationships between dNTP levels, DNA replication, and DSB induction in hypoxic GBM cancer cells, which is currently unknown. To bridge this knowledge gap, we exposed GBM cells to severe hypoxia and utilized cellular dNTP analysis to demonstrate that their dNTP pool can be elevated. Our result shows that elevating cellular dNTP pool relieved hypoxia-induced cell cycle arrest as determined by flow cytometry and increased their DNA replication. A single cell microscopic analysis also revealed that increasing the dNTP pool significantly enhanced the induction of DSBs following exposure to IR and bleomycin. Furthermore, we detected an increased efficacy of DSB-inducing agents in hypoxic GBM as demonstrated by apoptosis pathway activation. Our result suggest that increasing the intracellular dNTP pool in hypoxic GBM will stimulate DNA replication, increase genotoxin-induced DSB, and improve DSB-inducing therapeutics' efficacy. This study provides a preclinical justification for using cellular dNTP modulation as a novel therapeutic strategy and an adjunct to classical DSB-inducing agents in hypoxic GBM. Citation Format: Edidiong R. Usoro, Dominique Monroe, Kristen Carver, Maya Jenkins, Emily Steinbeck, Arilyn Williams, Shelby Aycox, Waaqo Daddacha. Understanding the role of dNTP pool on double-strand break and resistance to therapy in quiescent hypoxic glioblastoma [abstract]. In: Proceedings of the AACR Special Conference on Brain Cancer; 2023 Oct 19-22; Minneapolis, Minnesota. Philadelphia (PA): AACR; Cancer Res 2024;84(5 Suppl_1):Abstract nr B020.

Efficacious Factors in Pleural Malignancy Based on Characteristics of Pleural Fluid and Type of Primary Tumor in Shahid Sadouqhi and Shahid Rahmonun Hospitals of Yazd from 2019 to 2021

Efficacious Factors in Pleural Malignancy Based on Characteristics of Pleural Fluid and Type of Primary Tumor in Shahid Sadouqhi and Shahid Rahmonun Hospitals of Yazd from 2019 to 2021

Treatment of bone metastases from solid tumors with bone-modifying agents: a web survey of Italian oncologists investigating patterns of practice drug prescription and prevention of side effects

PurposeOptimal use of bone-modifying agents (BMAs) in patients with bone metastases from solid tumors is uncertain in some aspects: the drug choice; the planned treatment duration and long-term therapy; the prevention and management of possible side effects, including renal toxicity, hypocalcaemia, and medication-related osteonecrosis of the jaw (MRONJ).MethodsItalian oncologists were invited to fulfil a 24-question web survey about prescription of BMAs for bone metastases of breast cancer, prostate cancer, and other solid tumors. Prevention and management of side effects were also investigated.ResultsAnswers of 191 oncologists were collected. BMAs are usually prescribed at the time of diagnosis of bone metastases by 87.0% (breast cancer) and 76.1% (solid tumors except breast and prostate cancers) of oncologists; the decision is more articulated for prostate cancer (endocrine-sensitive versus castration-resistant). The creatinine level (32.3%), the availability of patient venous access (15.8%), and the type of primary neoplasm (13.6%) are the most reported factors involved in choice between bisphosphonates and denosumab. Zoledronic acid every 3 months was considered as a valid alternative to monthly administration by 94% of Italian oncologists. Oncologists reported a good confidence with measures aimed to prevent MRONJ, whereas uncertainness about prevention and management of hypocalcemia was registered.ConclusionItalian oncologists showed a high attitude in prescribing bisphosphonates or denosumab at the time of diagnosis of bone metastases, with a large application of preventive measures of side effects. Further studies are needed to investigate some controversial aspects, such as optimal drug treatment duration and long-term drug schedules.

Expression and Prognostic Role of PANK1 in Glioma.

Malignant gliomas are the most common type of primary malignant brain tumors. Pantothenate kinase 1 (PANK1) mRNA is highly expressed in several metabolic processes, implying that PANK1 plays a potential role in metabolic programming in cancers. However, the role of PANK1 in glioma has not been fully explored. Public datasets (The Cancer Genome Atlas (TCGA), Chinese Glioma Genome Atlas (CGGA), Gravendeel and Rembrandt) and validation cohort were used to explore the expression of PANK1 in glioma tissues. Kaplan-Meier and Cox regression analyses were used to explore the relationship between PANK1 and prognosis in glioma. Cell proliferation and invasion were determined using Cell Counting Kit-8 (CCK8) and transwell invasion in vitro assays. Analysis using the four public datasets and the validation cohort showed that PANK1 expression was significantly downregulated in glioma tissues compared with non-tumor tissues (P<0.01). PANK1 expression was negatively correlated with World Health Organization (WHO) grade, 1p/19q non-codeletion and isocitric dehydrogenase 1/2 (IDH1/2) wildtype. Furthermore, high expression of PANK1 was correlated with significantly better prognosis of glioma patients compared to patients with low expression of PANK1 (all P<0.01 in the four datasets). Besides, both lower-grade glioma (LGG) and glioblastoma multiform (GBM) patients with high expression of PANK1 had a significantly better prognosis than those with low expression of PANK1 in TCGA, Gravendeel and Rembrandt datasets (all P <0.01). Multivariate Cox regression analysis revealed that low PANK1 expression was an independent risk factor associated with a worse prognosis of glioma patients. Moreover, overexpression of PANK1 significantly inhibited the proliferation and invasion of U87 and U251 cells. PANK1 expression is downregulated in glioma tissues and is a novel prognostic biomarker in glioma patients.

KIF4A promotes epithelial-mesenchymal transition by activating the TGF-β/SMAD signaling pathway in glioma cells.

Gliomas are the most prevalent type of primary brain tumor, with poor prognosis reported in patients with high-grade glioma. Kinesin family member 4A (KIF4A) stimulates the proliferation, migration, and invasion of tumor cells. However, its function in gliomas has not been clearly established. Therefore, this study aimed to investigate the effects of KIF4A on the epithelial-mesenchymal transition and invasion of glioma cells. We searched The Cancer Genome Atlas and Chinese Glioma Genome Atlas databases to identify KIF4A-related signaling pathways and downstream genes. We further validated them using western blotting, transwell migration and invasion, wound-healing scratch, and dual-luciferase reporter assays in U251 and U87 human glioblastoma cells. Our analysis of the Cancer Genome Atlas and Chinese Glioma Genome Atlas data showed elevated KIF4A expression in patients with gliomas and was associated with clinical grade. Here, KIF4A overexpression promoted the migration, invasion, and proliferation of glioma cells, whereas KIF4A knockdown showed contrasting results. Gene Ontology (GO) and Gene Set Enrichment Analysis (GSEA) analyses demonstrated that KIF4A positively controls TGF-β/SMAD signaling in glioma cells. Additionally, genetic correlation analysis revealed that KIF4A transcriptionally controls benzimidazoles-1 expression in glioma cells. KIF4A promotes the epithelial-mesenchymal transition by regulating the TGF-β/SMAD signaling pathway via benzimidazoles-1 in glioma cells.

Characterization of pediatric non-hematopoietic tumor metastases to the central nervous system: A single institution review.

Central nervous system (CNS) metastases represent a small portion of pediatric CNS neoplasms and data surrounding this condition with high morbidity is scarce. Single institutional archival institutional pathology records between 1999 and 2022 were searched for patients over 21 years old and younger with CNS, dura, cranial nerve, CSF, or leptomeningeal metastases; 41 cases were identified. We documented primary tumor types and locations, metastasis locations, types of invasion (direct extension vs distant metastasis), times from imaging or pathologic diagnosis to CNS involvement, and outcomes. Distant metastasis was the most common mechanism of metastasis (n = 32, 78%). Interval times to CNS metastasis varied by both tumor type and primary tumor location. In this cohort, osteosarcoma portended the shortest survival following CNS metastasis. This study highlights the diverse mechanisms and locations of CNS involvement in pediatric CNS metastases and illuminates a need for varied monitoring strategies when considering primary tumor type and anatomic location.

Lethal Complications of Meningiomas: A Case Series.

Meningiomas are the most prevalent type of primary intracranial tumor in adults, comprising nearly one-third of all intracranial tumors. They are typically benign, slow-growing, and asymptomatic but may cause neurological symptoms as they expand due to mass effect. Classification is determined by World Health Organization (WHO) grades 1 to 3 following pathological examination corresponding to benign, atypical, and anaplastic (malignant), respectively, reflecting their rate of growth and risk of recurrence. The vast majority are WHO grade 1 and their slow growth permits timely presentation for elective resection; however, meningiomas in vulnerable locations and coexisting morbidities can result in sudden death. We present a series of four adult patients with meningiomas which resulted in death, including a case of fatal seizure, midline hemorrhagic meningioma, postresection meningitis, and compression of the cerebellum. Retrospective review of the authors' cases was conducted. Available pathology, medical, and autopsy records including gross images were reviewed in each case. The inclusion criteria were adult patients (>18 years old) and that the cause of death had to include meningioma. The four patients included a 61-year-old male, an 84-year-old female, a 62-year-old male, and a 37-year-old female. Qualitative; autopsy reports describing cause of death and pathology report findings including gross and microscopic analysis. Meningiomas are often benign in nature but can rarely result in death. Size and location of the tumor and risk factors are contributory. Autopsy examination can be instrumental in identifying the cause and mechanism of deaths associated with meningiomas.

Simultaneous inhibition of PI3K and PAK in preclinical models of neurofibromatosis type 2-related schwannomatosis

Neurofibromatosis Type 2 (NF2)-related schwannomatosis is a genetic disorder that causes development of multiple types of nervous system tumors. The primary and diagnostic tumor type is bilateral vestibular schwannoma. There is no cure or drug therapy for NF2. Recommended treatments include surgical resection and radiation, both of which can leave patients with severe neurological deficits or increase the risk of future malignant tumors. Results of our previous pilot high-throughput drug screen identified phosphoinositide 3-kinase (PI3K) inhibitors as strong candidates based on loss of viability of mouse merlin-deficient Schwann cells (MD-SCs). Here we used novel human schwannoma model cells to conduct combination drug screens. We identified a class I PI3K inhibitor, pictilisib and p21 activated kinase (PAK) inhibitor, PF-3758309 as the top combination due to high synergy in cell viability assays. Both single and combination therapies significantly reduced growth of mouse MD-SCs in an orthotopic allograft mouse model. The inhibitor combination promoted cell cycle arrest and apoptosis in mouse merlin-deficient Schwann (MD-SCs) cells and cell cycle arrest in human MD-SCs. This study identifies the PI3K and PAK pathways as potential targets for combination drug treatment of NF2-related schwannomatosis.

Resolving the heterogeneous tumour microenvironment in cardiac myxoma through single-cell and spatial transcriptomics.

Cardiac myxoma (CM) is the most common (58%-80%) type of primary cardiac tumours. Currently, there is a need to develop medical therapies, especially for patients not physically suitable for surgeries. However, the mechanisms that shape the tumour microenvironment (TME) in CM remain largely unknown, which impedes the development of targeted therapies. Here, we aimed to dissect the TME in CM at single-cell and spatial resolution. We performed single-cell transcriptomic sequencing and Visium CytAssist spatial transcriptomic (ST) assays on tumour samples from patients with CM. A comprehensive analysis was performed, including unsupervised clustering, RNA velocity, clonal substructure inference of tumour cells and cell-cell communication. Unsupervised clustering of 34 759 cells identified 12 clusters, which were assigned to endothelial cells (ECs), mesenchymal stroma cells (MSCs), and tumour-infiltrating immune cells. Myxoma tumour cells were found to encompass two closely related phenotypic states, namely, EC-like tumour cells (ETCs) and MSC-like tumour cells (MTCs). According to RNA velocity, our findings suggest that ETCs may be directly differentiated from MTCs. The immune microenvironment of CM was found to contain multiple factors that promote immune suppression and evasion, underscoring the potential of using immunotherapies as a treatment option. Hyperactive signals sent primarily by tumour cells were identified, such as MDK, HGF, chemerin, and GDF15 signalling. Finally, the ST assay uncovered spatial features of the subclusters, proximal cell-cell communication, and clonal evolution of myxoma tumour cells. Our study presents the first comprehensive characterisation of the TME in CM at both single-cell and spatial resolution. Our study provides novel insight into the differentiation of myxoma tumour cells and advance our understanding of the TME in CM. Given the rarity of cardiac tumours, our study provides invaluable datasets and promotes the development of medical therapies for CM.

Extracellular Vesicles Derived from Glioma Stem Cells Affect Glycometabolic Reprogramming of Glioma Cells Through the miR-10b-5p/PTEN/PI3K/Akt Pathway.

Glioma is one of the most prevalently diagnosed types of primary malignant brain tumors. Glioma stem cells (GSCs) are crucial in glioma recurrence. This study aims to elucidate the mechanism by which extracellular vehicles (EVs) derived from GSCs modulate glycometabolic reprogramming in glioma. Xenograft mouse models and cell models of glioma were established and treated with GSC-EVs. Additionally, levels and activities of PFK1, LDHA, and FASN were assessed to evaluate the effect of GSC-EVs on glycometabolic reprogramming in glioma. Glioma cell proliferation, invasion, and migration were evaluated using MTT, EdU, Colony formation, and Transwell assays. miR-10b-5p expression was determined, with its target gene PTEN and downstream pathway PI3K/Akt evaluated. The involvement of miR-10b-5p and the PI3K/Akt pathway in the effect of GSC-EVs on glycometabolic reprogramming was tested through joint experiments. GSC-EVs facilitated glycometabolic reprogramming in glioma mice, along with enhancing glucose uptake, lactate level, and adenosine monophosphate-to-adenosine triphosphate ratio. Moreover, GSC-EV treatment potentiated glioma cell proliferation, invasion, and migration, reinforced cell resistance to temozolomide, and raised levels and activities of PFK1, LDHA, and FASN. miR-10b-5p was highly-expressed in GSC-EV-treated glioma cells while being carried into glioma cells by GSC-EVs. miR-10b-5p targeted PTEN and activated the PI3K/Akt pathway, hence stimulating glycometabolic reprogramming. GSC-EVs target PTEN and activate the PI3K/Akt pathway through carrying miR-10b-5p, subsequently accelerating glycometabolic reprogramming in glioma, which might provide new insights into glioma treatment.

Doxorubicin-Loaded Microalgal Delivery System for Combined Chemotherapy and Enhanced Photodynamic Therapy of Osteosarcoma.

Osteosarcoma (OS) is considered the most frequent type of primary malignant bone tumor. Currently, radiotherapy, photodynamic (PDT), and other therapies for osteosarcoma are limited by tumor hypoxia and single efficacy and serve side-effects. Herein, we reported a microalgal drug delivery system (SpiD), doxorubicin (DOX)-loaded Spirulina platensis (Spi) for OS therapy. The specific surface of Spirulina platensis allowed for effective loading of DOX via surface channels and electrostatic interactions. Under 650 nm laser irradiation, SpiD enabled high oxygen production by photosynthesis and enhanced reactive oxygen species (ROS) generation via chlorophyll-assisted photosensitization, synergistically killing tumor cells with the released DOX. Combined chemotherapy and enhanced PDT mediated by SpiD exerted synergic antitumor effects and resulted in potent therapeutic efficacy in orthotopic osteosarcoma mice. Furthermore, SpiD could reduce the side-effects of chemotherapy, showing excellent blood and tissue safety. Taken together, this microalgal drug delivery system provided a natural, efficient, safe, and inexpensive strategy for OS treatment.

Clinical features and prognostic factors of patients with cancer-associated stroke.

Cerebrovascular diseases in cancer patients significantly aggravate their condition and prognosis; therefore, prompt and accurate diagnosis and treatment are important. The purpose of this study was to investigate patient demographics, laboratory data, brain magnetic resonance imaging (MRI) findings, and prognosis among patients with stroke and cancer, especially cancer-associated ischemic stroke (CAIS). We performed a retrospective, single-center study. We enrolled consecutive patients who had acute stroke and were admitted to our hospital between January 2011 and December 2021. We collected general demographic characteristics, cancer histopathological type, laboratory data, brain MRI findings, and prognosis data. Among 2040 patients with acute stroke, a total of 160 patients (7.8%) had active cancer. The types of strokes were cerebral infarction, cerebral hemorrhage, subarachnoid hemorrhage, and transient ischemic attack in 124, 25, 5, and 6 patients, respectively. Among the patients with ischemic stroke, there were 69 cases of CAIS. Pancreas and adenocarcinoma were the most frequent types of primary tumor and histopathology. Patients with adenocarcinoma and those with cerebral infarctions in both bilateral anterior and posterior cerebral circulation areas showed higher D-dimer levels. Pancreatic cancer and high plasma D-dimer levels were associated with poor survival rate. CAIS was seen more frequently in patients with pancreatic cancer and adenocarcinoma. Pancreatic cancer and high plasma D-dimer levels were potential factors of poor prognosis in patients with CAIS.

Clinicopathological features and clinical outcomes in individuals with Krukenberg tumors of colorectal origin.

191 Background: Krukenberg tumors (KT) are metastases to the ovary generally originating from a gastrointestinal primary such as colorectal carcinoma. The prognosis is poor with KT, and clinicopathological features associated with clinical outcomes have not been extensively studied. The study aimed to investigate the associations of clinicopathological features with outcomes in patients with KT of colorectal carcinoma (CRC) origin. Methods: This retrospective study utilized medical records and patient registries to identify 160 patients with a confirmed histopathological diagnosis of KT at Stanford University Medical Center between 2000 and 2020. Data collection included demographics, historical, clinicopathological, treatment and outcome variables. The primary tumor type was (N, %): CRC (101, 63.1%); gastric (24, 15%), breast (13, 8.1%); small bowel (10, 6.2%), other (12, 7.5%). Statistical analysis was performed using Chi-squared, Mann-Whitney U, and log-rank Kaplan-Meier analysis. Results: Analysis of the CRC cohort subdivided by location of the primary, N: 45 vs. 56, right colon (R) vs. left colon (L) revealed no significant difference in median age at diagnosis of KT, race/ethnicity, oligometastatic disease, histopathological differentiation or ovarian tumor volume. Patients with R vs L sided CRC primaries had a higher proportion of synchronous presentation at the time of KT diagnosis (75.6% vs 41.1%, R vs L, p&lt;0.001). Time to progression was not different, but overall survival (OS) was shorter in R CRC (767 vs. 1246 days, R vs. L, p &lt;0.01). By Kaplan-Meier analysis, patients with R CRC had a shorter OS (log-rank p=0.016). In the subgroup with unilateral KT, R sided CRC primaries involved the R ovary (85%) whereas L-sided CRC primaries involved the L ovary (70%) ( χ2, p&lt;0.002). Patient with bilateral (B) versus unilateral (U) had a larger ovarian tumor volume (2,073cm3 vs. 307 cm3, p&lt;0.01) but no difference in oligometastatic disease, chronicity, time to progression or overall survival. There was no statistical difference (p=0.93) between the association of bilateral KT inter-ovarian tumor size and CRC Laterality within individual patients. Conclusions: In this study, KT tumors predominantly originate from CRC. The clinical features of R versus L CRC, such as chronicity and OS are conveyed prognostically in patients with KT. Individuals with L CRC exhibited a better overall prognosis compared to those with R CRC. In patients with unilateral KT metastasis to ipsilateral ovary is significantly associated with location of CRC and is suggestive of a retrograde lymphatic or transcoelomic route of metastatic spread. Further studies are needed to confirm these findings and to elucidate ovarian organ tropism mediators that facilitate development and growth in metastatic ovarian cancer.

Expression of claudin 18.2 in peritoneal metastasis (PM) of gastric cancer.

403 Background: Prognosis of patients with gastric cancer (GC) with peritoneal metastasis (PM) still remains poor, and new treatment strategies are needed. Claudins (CLDNs) are main components of tight junctions that physiologically mediate cell–cell adhesion and regulate selective permeability in epithelial cellular sheets. Recent clinical trials have demonstrated that monoclonal antibodies (mAb) to CLDN18.2 have been shown to improve the outcome of the patients with unresectable metastatic GC, especially with undifferentiated histology. However, the clinical effects of the anti-CLDN18.2 mAb for patients with PM is unclear. In this study, we evaluated the expression of CLDN18.2 in primary tumor and metastatic nodules in peritoneum of GC using immunohistochemical (IHC) staining. Methods: In 42 patients diagnosed with stage IV GC with PM at our Department from 2014 to 2022, biopsy samples of primary tumor and peritoneal nodules were obtained and the expression of CLDN18.2 in tumor cells by IHC staining using specific antibody for CLDN18.2 (clone: 43-14A, prediluted; Ventana) followed by the incubation with secondary antibody and the primary antibody binding visualized using the DAB IHC Detection Kit. The intensity of the membrane and cytosolic staining was classified as 0 (no reactivity), 1+ (weak), 2+ (moderate), and 3+ (strong). Samples were defined as CLDN18.2-positive when tumor cells showed specific staining with at least 1+ intensity in tumor cells. Percentage of overall CLDN18.2 positive cells was determined by the estimated number of CLDN18.2+ cells divided by the estimated overall number of tumor cells in any fractions. Her2 expression was also examined in parallel. Results: The histology type of primary tumor was differentiated in 7, undifferentiated in 33, and unknown in 2 patients. CLDN18.2-positivity was detected in 31 (74%) of primary tumors, including 5 (71%) differentiated and 26(79%) undifferentiated tumors. CLDN18.2 was positively detected in 15 (35%) disseminated nodules, in 4 (57%) differentiated and 11 (33%) in undifferentiated cases, respectively. All these cases also showed CLDN18.2-positve in primary sites. However, expression of CLDN18.2 in PM was not detected in 16 (52%) cases which showed CLDN18.2-positive for primary tumor. Moderate-to-strong CLDN18.2 expression (≥2+ membrane staining intensity in ≥40% of tumor cells) was observed in 13 (31%) of primary tumor, but only in 2 (5%) of PM. HER2 was positive in 5 (12%) patients, and no correlation was observed between HER2 and CLDN18.2 expression. Conclusions: CLDN18.2 expression did not show significant difference depending on histology. Although the expression of CLDN18.2 in PM showed homology with that in biopsy sample of primary gastric tumor, its expression level generally decreased in PM. Investigation of CLDN18.2 expression in peritoneal nodules might be necessary to predict the clinical response of CLDN18.2 mAb for GC with PM.

Patient-reported outcomes: The unmet needs of the gastrointestinal cancer community.

731 Background: According to the World Health Organization International Agency for Research on Cancer, gastrointestinal (GI) cancers account for 1 in 4 cancer cases and 1 in 3 cancer-related deaths worldwide. An estimated 4.8 million new cases of GI cancers and 3.4 million related deaths occur annually. Understanding the need for increased GI cancer awareness, patient education and support, the GI Cancers Alliance developed a series of engagement activities for the GI cancer community as a needs assessment to identify critical gaps in support services, fragmented education, and disease awareness. Methods: Our 12-month patient-reported outcomes (PRO) research included an online anonymous survey, individual and small group interviews, focus groups, advisory boards, and an interactive workshop at the 2023 American Society of Clinical Oncology annual meeting. 1,122 patients participated during this 12-month PRO research period. Participants reported being diagnosed with one of the following GI cancer primary tumor types: Anus (3%), Appendix (2%), Bile Duct (6%), Colon (19%), Esophagus (7%), Gallbladder (5%), Gastric (14%), GI NET / GI Carcinoid Tumor (3%), Liver (7%), Pancreas (6%), Small Intestine (4%), Rectum (23%), Unknown primary location (1%). Results: Overarching areas of unmet need include: health disparities throughout the care continuum for underserved populations (21%); lack of adequate precision oncology patient education, including biomarker education and testing (19%); the rise of early-age onset (EAO) in GI cancers and the unique needs of the young adult (YA) population (18%); nutritional wellness education (17%); insufficient support for family caregivers and caregiver respite services (16%) scarcity of patient-centered care and adequate patient-clinician communication (11%). Conclusions: Our PRO research underscores the unmet needs and gaps in support services of the GI cancer community. Our global call to action includes partnering with our 100+ member organizations to amplify the patient voice and patient-lived experience, and cross-collaboration with our community of advocates, patients, caregivers, and clinicians. Our shared call to action and continued collaboration provides a greater impact for our GI cancer community to help meet patient needs and eliminate critical gaps in services.

SBRT with ipilimumab and nivolumab to metastatic MSS colorectal and pancreatic cancer: A pooled analysis of four prospective phase II trials.

752 Background: The role of immunotherapy (IO) in microsatellite stable (MSS) pancreatic and colorectal cancer is limited. Stereotactic body radiation therapy (SBRT) is increasingly used in the limited metastatic setting, however its use with IO remains an area of investigation for both target response and overall systemic response. Here we evaluate the local failure rate of irradiated target lesions with and without IO. Methods: We pooled four prospective phase II single-arm studies of patients with metastatic MSS colorectal or pancreatic cancer treated with SBRT alone or with IO. Those in the first study (NCT01239381) received ablative liver SBRT to a maximum biologically effective dose (BED) of 48-100 Gy. Patients in the remaining studies received low dose SBRT to liver, lung, or nodal metastases with 24 Gy in 3 fractions to a BED of 43.2 Gy in combination with Ipilimumab and Nivolumab during the first (NCT04361162, NCT04575922) or second (NCT03104439) cycles. Local failure rates at the time of first progression were estimated by the cumulative incidence with non-target progression only and death as competing risks and compared using Gray’s test. The best response at the target was measured with the RECIST 1.1 criteria using the largest reduction in target size during follow up. Fisher’s exact test was used to compare objective response (ORR) and disease control rates (DCR), while the Wilcoxon rank sum test was performed to compare target size and percentage of tumor reduction. Results: Across all four studies there were 154 evaluable patients including 50 who received ablative SBRT and 104 patients who received low dose SBRT with IO. There were 92 patients with colorectal and 62 with pancreatic cancer. Median target size was 3.7 cm in the ablative SBRT group and 2.8 cm in the IO group (P=0.04). The 6-month, 1-year, and 2-year local failure rates were 10%, 18%, and 20% respectively following ablative SBRT and 24%, 25%, and 26% following low dose SBRT with IO (P=0.32). The ORR was 50.0% with SBRT alone and 23.1% with the addition of IO (P=0.001). There was no significant difference in the DCR (80.0% vs. 68.3%, P=0.18). The percent decrease in size was significantly higher in those with ablative SBRT (median -53.0% vs. -10.6%, p=0.02). There was no difference in the percent tumor response with respect to primary tumor type (P=0.13), KRAS (P=0.11) or TP53 (P=0.27) status. Conclusions: Despite the use of low dose SBRT with immune checkpoint inhibitors, there was no significant difference in local failure rates compared to ablative SBRT. Ablative SBRT dosing yielded a significantly higher depth of response. As clinical and preclinical studies suggest liver metastases are less responsive to IO, understanding dose and fractionation schemas for optimal local control is critical. Further studies are needed to explore the radiation dose with regards to local control when delivered with IO.

Pathological characteristics of lung tumors in Sri Lanka 2017-2021.

The prevalence of lung cancer is steadily increasing globally, and it is projected to become the second most prevalent cancer in men by 2030. Lung cancer is the leading cause of cancer-related deaths worldwide, accounting for approximately 3.61% of total fatalities. Despite its significant impact, many Asian countries, including Sri Lanka, lack precise data on the epidemiological patterns of lung tumors. This study pioneers a comprehensive exploration in Sri Lanka, delving into the demographic and clinicopathological characteristics of lung cancer patients. The study included 733 consecutive patients with lung tumors from 2017 to 2021, with a median age of 59 years. The most common site of tumors was the right lower lobe and left upper lobes. Adenocarcinoma was the most prevalent histopathological type of primary malignant lung tumors, while colorectal adenocarcinomas were the most common cause of metastatic deposits in the lungs. The most common benign tumor was hamartoma. Significantly, our findings unveiled associations between patient demographics and tumor types, underscoring the importance of factoring in age and gender in diagnostic assessments. Notably, the absence of a dedicated lung cancer screening program in Sri Lanka underscores the critical reliance on clinical suspicion and accurate diagnostic methods.

Increase of KLK7, cytokeratin 5/6, and elafin expression in head and neck squamous cell carcinoma compared with lung squamous cell carcinoma

ABSTRACT Squamous cell carcinoma is the most common primary tumor in the head and neck epithelium and is the second most common primary tumor type in the lung. Although morphologically indistinguishable from each other with hematoxylin and eosin stain on histology, the tumors have different protein expression profiles. Using 24 formalin-fixed paraffin embedded squamous cell carcinomas of the lung and 24 squamous cell carcinomas in the head and neck, protein expression for cytokeratin 5/6, kallikrein 7, and elafin was evaluated by immunohistochemistry. All three proteins were found to evidence higher expression in head and neck squamous cell carcinoma as compared with that of squamous cell carcinoma of the lung. The differences in expression may help clinical differentiation between primary tumors of the lung from metastatic tumors to the lung from the oral/laryngeal cavities.

A noval noninvasive targeted therapy for osteosarcoma: the combination of LIFU and ultrasound-magnetic-mediated SPIO/TP53/PLGA nanobubble.

Osteosarcoma (OS) is the most common type of primary malignant bone tumor. Transducing a functional TP53 gene can effectively inhibit OS cell activity. Poly lactic acid-glycolic acid (PLGA) nanobubbles (NBs) mediated by focused ultrasound (US) can introduce exogenous genes into target cells in animal models, but this technique relies on the passive free diffusion of agents across the body. The inclusion of superparamagnetic iron oxide (SPIO) in microbubbles allows for magnetic-based tissue localization. A low-intensity-focused ultrasound (LIFU) instrument was developed at our institute, and different intensities of LIFU can either disrupt the NBs (RLI-LIFU) or exert cytocidal effects on the target tissues (RHI-LIFU). Based on these data, we performed US-magnetic-mediated TP53-NB destruction and investigated its ability to inhibit OS growth when combined with LIFU both in vitro and in vivo. Several SPIO/TP53/PLGA (STP) NB variants were prepared and characterized. For the in vitro experiments, HOS and MG63 cells were randomly assigned into five treatment groups. Cell proliferation and the expression of TP53 were detected by CCK8, qRT-PCR and Western blotting, respectively. In vivo, tumor-bearing nude mice were randomly assigned into seven treatment groups. The iron distribution of Perls' Prussian blue-stained tissue sections was determined by optical microscopy. TUNEL-DAPI was performed to examine apoptosis. TP53 expression was detected by qRT-PCR and immunohistochemistry. SPIO/TP53/PLGA NBs with a particle size of approximately 200nm were prepared successfully. For in vitro experiments, ultrasound-targeted transfection of TP53 overexpression in OS cells and efficient inhibition of OS proliferation have been demonstrated. Furthermore, in a tumor-bearing nude mouse model, RLI-LIFU-magnetic-mediated SPIO/TP53/PLGA NBs increased the transfection efficiency of the TP53 plasmid, resulting in apoptosis. Adding RHI-LIFU to the treatment regimen significantly increased the apoptosis of OS cells in vivo. Combining LIFU and US-magnetic-mediated SPIO/TP53/PLGA NB destruction is potentially a novel noninvasive and targeted therapy for OS.

Clinical and Bronchoscopy Assessment in Diagnosing the Histopathology Type of Primary Central Lung Tumors.

The location and type of a tumor influence the prognosis of lung cancer. Primary Central Lung Tumors (PCLTs) are correlated with poor prognoses and certain histologic types. This study aimed to present a comprehensive exploration of clinical and bronchoscopic assessments for diagnosing the histopathology types of PCLTs and identified the factors associated with certain histologic types. This was an observational cross-sectional study of PCLTs, defined as tumors in direct contact with hilar structures or located within the inner two-thirds of the hemithorax. We gathered demographic and clinical data, as well as data on bronchoscopy assessment and histopathology type. Tumor stage, symptoms of superior vena cava syndrome, and enlargement of lymph nodes in the paratracheal and subcarinal regions were also documented. Of the 895 patients, 37.87% had primary lung tumors, with 17.76% classified as PCLTs. Notably, PCLT cases exhibited a higher proportion of stage III (28.9% vs. 18.3%; p = 0.03) and Squamous Cell Carcinoma (SCC) histopathology (37.1% vs. 17.2%; p = 0.00) compared with non-PCLT cases. Bronchoscopic findings in PCLTs revealed a predilection for central airway masses (25.2%) and compressive distal airway stenosis (25.2%). Subgroup analysis of 159 PCLT cases identified 37.10% as SCC. Multivariate analysis underscored that intraluminal masses predict central SCC (odds ratio 2.075, 95% confidence interval 1.07-3.99; p = 0.028). The proportion of stage III, SCC histopathological type, and intraluminal lesions was higher in patients with PCLT than in non-PCLT cases. The presence of intraluminal lesions can predict the histopathological type of SCC in patients with PCLTs.