United States

Abstract Title: Vagus Nerve Stimulation Ameliorates Inflammatory Skin Diseases through Systemic Anti-Inflammatory Pathways: Evidence from Murine Models of Psoriasis and Atopic Dermatitis
William J. Nahm,1 Ki Joong Kim,2 Eui Namgung,3 Vincent Falanga,4

1) New York University Grossman School of Medicine, New York, NY, USA
2) Department of Oriental Medicine, Daejeon University, Daejeon, ROK
3) Department of Physics, University of California, San Diego, La Jolla, CA, USA
4) Department of Dermatology, Boston University Chobanian and Avedisian School of Medicine, Boston, MA, USA

Background: The cholinergic anti-inflammatory pathway, activated through vagus nerve stimulation (VNS), plays a crucial role in immune response regulation. Although the skin lacks direct vagal nerve (VN) innervation, VNS may influence cutaneous inflammatory disorders through indirect mechanisms. In recent years, VNS has shown promise in modulating rheumatoid arthritis, inflammatory bowel disease, and other conditions, such as cardiovascular disease. This study investigated whether VNS could improve inflammatory skin diseases by modulating systemic inflammatory responses and local inflammatory cytokines.

Methods: Two distinct murine models were employed: C57/BL6 mice with imiquimod-induced psoriasis lesions and NC/Nga mice with dinitrochlorobenzene (DNCB)-induced atopic dermatitis. In the imiquimod model, psoriasis-like lesions were induced by applying imiquimod 5% cream to shaved dorsal skin for seven consecutive days, followed by every other day for six days. The DNCB model involved sensitization with 1% DNCB for seven days, followed by 0.3% DNCB for three days, resulting in marked scaling, crusting, and exudate formation. Cervical VNS (5V/5mA/5Hz/5ms/5min) was administered at 6- and 24-hour pre-sacrifice in the imiquimod model, and 24 hours pre-sacrifice in the DNCB model. Outcomes were assessed through clinical evaluation, histological analysis, immunofluorescence staining, western blotting, and cytokine measurement in plasma and splenic tissue.

Results: The application of imiquimod and DNCB produced psoriatic and eczematous-type clinical inflammation, accompanied by markedly increased epidermal thickening. VNS significantly reduced epidermal thickening and attenuated clinical manifestations in both models. In the imiquimod model, VNS produced a moderate reduction of erythema, scaling, and crusting. The DNCB-induced dermatitis was dramatically ameliorated following VNS treatment. Both models demonstrated significant reduction in pro-inflammatory cytokine expression (TNF-α, IL-6, IL-1β) and decreased CD11b-positive cutaneous macrophage infiltration. Immunofluorescence confirmed decreased epidermal TNF-α expression post-VNS. A single VNS application in DNCB-treated mice resulted in a 32% reduction in plasma TNF-α concentrations (p &lt; 0.01). Notably, the protein levels of TNF-α and IL-1β, which were elevated in splenic tissue in both inflammatory models, were subsequently downregulated by VNS treatment.

Conclusion: These findings establish VNS as a promising therapeutic approach for inflammatory skin diseases. The therapeutic effects appear to be mediated through the modulation of systemic and subsequently local inflammation. These findings suggest that cutaneous inflammatory disorders may be linked to systemic inflammatory processes, providing mechanistic insights into the anti-inflammatory effects of VNS in dermatological conditions. Additionally, VN dysregulation emerges as a potential unifying mechanism underlying the well-established association between inflammatory skin diseases and their systemic comorbidities.

AMA Research Challenge 2025 

Vagus Nerve Stimulation Ameliorates Inflammatory Skin Diseases through Systemic Anti-Inflammatory Pathways: Evidence from Murine Models of Psoriasis and Atopic Dermatitis

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Abstract Title: Vagus Nerve Stimulation Ameliorates Inflammatory Skin Diseases through Systemic Anti-Inflammatory Pathways: Evidence from Murine Models of Psoriasis and Atopic Dermatitis
William J. Nahm,1 Ki Joong Kim,2 Eui Namgung,3 Vincent Falanga,4

1) New York University Grossman School of Medicine, New York, NY, USA
2) Department of Oriental Medicine, Daejeon University, Daejeon, ROK
3) Department of Physics, University of California, San Diego, La Jolla, CA, USA
4) Department of Dermatology, Boston University Chobanian and Avedisian School of Medicine, Boston, MA, USA

Background: The cholinergic anti-inflammatory pathway, activated through vagus nerve stimulation (VNS), plays a crucial role in immune response regulation. Although the skin lacks direct vagal nerve (VN) innervation, VNS may influence cutaneous inflammatory disorders through indirect mechanisms. In recent years, VNS has shown promise in modulating rheumatoid arthritis, inflammatory bowel disease, and other conditions, such as cardiovascular disease. This study investigated whether VNS could improve inflammatory skin diseases by modulating systemic inflammatory responses and local inflammatory cytokines.

Methods: Two distinct murine models were employed: C57/BL6 mice with imiquimod-induced psoriasis lesions and NC/Nga mice with dinitrochlorobenzene (DNCB)-induced atopic dermatitis. In the imiquimod model, psoriasis-like lesions were induced by applying imiquimod 5% cream to shaved dorsal skin for seven consecutive days, followed by every other day for six days. The DNCB model involved sensitization with 1% DNCB for seven days, followed by 0.3% DNCB for three days, resulting in marked scaling, crusting, and exudate formation. Cervical VNS (5V/5mA/5Hz/5ms/5min) was administered at 6- and 24-hour pre-sacrifice in the imiquimod model, and 24 hours pre-sacrifice in the DNCB model. Outcomes were assessed through clinical evaluation, histological analysis, immunofluorescence staining, western blotting, and cytokine measurement in plasma and splenic tissue.

Results: The application of imiquimod and DNCB produced psoriatic and eczematous-type clinical inflammation, accompanied by markedly increased epidermal thickening. VNS significantly reduced epidermal thickening and attenuated clinical manifestations in both models. In the imiquimod model, VNS produced a moderate reduction of erythema, scaling, and crusting. The DNCB-induced dermatitis was dramatically ameliorated following VNS treatment. Both models demonstrated significant reduction in pro-inflammatory cytokine expression (TNF-α, IL-6, IL-1β) and decreased CD11b-positive cutaneous macrophage infiltration. Immunofluorescence confirmed decreased epidermal TNF-α expression post-VNS. A single VNS application in DNCB-treated mice resulted in a 32% reduction in plasma TNF-α concentrations (p < 0.01). Notably, the protein levels of TNF-α and IL-1β, which were elevated in splenic tissue in both inflammatory models, were subsequently downregulated by VNS treatment.

Conclusion: These findings establish VNS as a promising therapeutic approach for inflammatory skin diseases. The therapeutic effects appear to be mediated through the modulation of systemic and subsequently local inflammation. These findings suggest that cutaneous inflammatory disorders may be linked to systemic inflammatory processes, providing mechanistic insights into the anti-inflammatory effects of VNS in dermatological conditions. Additionally, VN dysregulation emerges as a potential unifying mechanism underlying the well-established association between inflammatory skin diseases and their systemic comorbidities.

poster

Background
The diversity of colon cancer treatments allows the potential personalization of regimens for individuals, such as existing targeted therapies for mutations in BRAF, KRAS, and PIK3CA. While studies have analyzed patient responses to colon cancer therapies based on genetic mutations in a handful of genes, our research takes a comprehensive approach by examining the interplay between a larger set of mutated cancer-critical genes and treatment options. This project aims to explore the relationships between colon cancer mutations, treatment plans, and responses to determine how genetic mutations influence the outcomes to certain regimens. 

Methods
Clinical data for 181 colon cancer patients was obtained from the Prisma Health Cancer Institute’s Biorepository derived from EPIC®. The mutation status of 50 cancer-critical genes in those patients was determined through multiplex PCR using Ion Ampliseq Cancer Hotspot panel v2 by Precision Genetics and USC Functional Genomics Core. During analysis, multiple rounds of treatment were subdivided, with a single data observation corresponding to the applied treatment regimen and response for each round. Data analysis was performed using Microsoft Excel and R (version 4.4.2) to assess patient demographics, frequencies of mutations, and treatment regimens. 

Results
The most frequently mutated genes in this group of colon cancer patients were TP53 (54.1%), KRAS (37.6%), APC (33.7%), KDR (29.8%), and PIK3CA (25.4%). A greater proportion of Black patients had mutated JAK3 compared to White patients (p < 0.001), with 88.9% of Black patients having a p.Pro132Thr JAK3 mutation. FOLFOX (fluorouracil, leucovorin, oxaplatin) treatment alone was utilized in 23.9% of the colon cancer therapies, capecitabine in 14.9%, FOLFOX + bevacizumab in 11.7%, FOLFIRI (fluoruracil, irinotecan, leucovorin) in 7.2%, and the remaining treatment regimens being comprised of various combinations of these therapies alongside other chemotherapeutic drugs. 

Conclusion
Our preliminary analysis shows the variety of genes mutated in the colon cancer dataset, highlighting the predominance of TP53, KRAS, and APC. This supports the frequencies of mutated genes observed in previous studies, reinforcing the dataset’s quality and potential for ongoing analysis. The higher frequency of JAK3 mutations in Black patients sparks interest and requires further exploration, as JAK3 is rarely discussed in prior literature in the setting of colon cancer but has been associated with poorer outcomes in other solid tumors such as gastric. As we continue our research, we aim to identify correlations between mutated genes, treatments, and patient outcomes in an effort to pave the way for improving therapeutic strategies. 


Precision Pursuits: Navigating Colon Cancer’s Genetic Maze

Background: Glaucoma is characterized by the insidious degeneration of Retinal Ganglion Cells (RGCs). Such degeneration can be monitored with the Combined Structure Function Index (CSFI), which can generate an estimated RGC count (eRGCC) to identify early glaucomatous change. In this study, we examine the relationship between enlargement of the Foveal Avascular Zone, a capillary free region of the macula, with decreasing eRGCC, to investigate loss of microvascular integrity as a potential etiology for eRGCC decline.

Methods: Five subjects (9 eyes) underwent comprehensive eye exam, OCT for eRGCC calculation, and OCT-A for FAZ area calculation. Pearson correlation and linear regression were used.

Results: Subjects averaged 55±15 years old, with a mean eRGCC of 892,514± 2,222. A significant negative correlation was found between FAZ and eRGCC (r2 = -0.915, p=0.01). in a linear regression model, FAZ as a predictor explained 5.1% of variance in eRGCC (p=0.010), while age, hypertension, and diabetes account for 93.9% (p=0.002). Every 0.01mm2 rise in FAZ was associated with a 327 eRGCC loss.

Conclusion: Increase in FAZ correlates with eRGCC loss in Glaucoma Suspects, implicating a vascular etiology of Glaucoma.

Increased Foveal Avascular Zone Area Predicts Decreased Estimated Retinal Ganglion Cell Count in Glaucoma Suspects: A Pilot Study

Background
Medial meniscus posterior horn root tears (MMPRTs) are injuries of the knee causing cartilage displacement, leading to accelerated osteoarthritis. MMPRTs are associated with meniscal extrusion, defined as radial displacement >=3 mm of the meniscus. Quantitative MRI, particularly T2 and T2* relaxation time mapping, can distinguish between normal vs. torn or degenerative menisci. This study focuses on 3D T2* mapping in evaluating medial meniscal extrusion between patients before and six months after surgical repair of MMPRTs, compared to healthy controls. We hypothesize that MMPRTs increase T2* values, and that relaxation times correlate with medial meniscus extrusion measurements taken before and after repair.

Methods
This study involved fifteen patients with a unilateral posterior root tear of the medial meniscus and nine healthy controls. Each patient underwent the same MRI protocol twice using a 7T MRI system—once before repair and again six months after repair—while the control group had one scan.

The MRI protocol included T2-weighted turbo-spin echo and 3D SPACE sequences with fat suppression. Multi-echo T2* data were used to fit a mono-exponential signal decay through a two-parametric least-squares fitting routine, with fitting accuracy assessed by normalizing the root mean square error (RMSE) to estimated signal intensity at an echo time of 0 ms.

Manual 3D segmentation was performed on T2*-weighted images using ITK-SNAP to capture the 3D structure of the medial meniscus.

Median T2* values and RMSEs were calculated. Meniscal extrusion was assessed on coronal T2-weighted images with fat suppression by drawing two vertical lines at the peripheral margins of the tibial plateau and the outermost edge of the meniscal body. A linear mixed-effects model was used for comparisons, and Pearson correlation analysis was employed.

Results
Significantly longer T2* values (p<0.05) were observed in the medial meniscus of patients before and six months after repair of the root tear. Post-repair patients showed significantly higher T2* values in the posterior horn of the medial meniscus compared to pre-repair patients. RMSE was below 4.3% for all regions, indicating good reliability. Extrusion measurements in post-repair patients were significantly correlated with T2* values in both pre-repair (r=0.826; p<0.001) and post-repair (r=0.732; p=0.002) patients. 

Conclusion
Findings show strong correlations between T2* mapping and meniscal extrusion, emphasizing the connection between altered structural integrity and tissue laxity. 3D quantitative T2* mapping is a potent tool in evaluating meniscal extrusion in patients with MMPRTs, which can ultimately improve surgical outcomes and patient quality of life.


3D T2* Mapping of Medial Meniscus Extrusion at 7T Before and After Posterior Root Tear Repair

Abstract Title 
Pseudocyesis versus Delusional Pregnancy in a Young Adult with history of Neuroblastoma 

Background 
Pseudocyesis, or false pregnancy, is a rare psychosomatic condition characterized by the belief of being pregnant accompanied by objective signs of pregnancy without actual conception. This condition poses diagnostic challenges, particularly in patients with complex medical histories requiring multidisciplinary care approaches. 

Case Presentation 
We report the case of a 23-year-old female with a history of neuroblastoma who presented with pseudocyesis. The patient experienced multiple emergency department visits over several months, presenting with symptoms consistent with pregnancy including amenorrhea, abdominal distension, and subjective fetal movement. Initial clinical suspicion prompted extensive workup including serial beta-HCG levels and pelvic ultrasounds. Despite repeatedly negative pregnancy tests and imaging studies showing no evidence of intrauterine pregnancy, the patient maintained firm conviction of being pregnant and continued to report symptoms. 

The patient's presentation was complicated by her oncological history, requiring careful consideration of potential malignancy recurrence versus psychiatric etiology. Multiple laboratory investigations and imaging studies were performed to exclude organic causes, including tumor markers and advanced imaging. The persistence of symptoms despite negative objective findings led to psychiatric admission. 

Successful management required close collaboration between primary care physicians, emergency medicine, gynecology, and psychiatry services. This case highlights the importance of early psychiatric involvement in suspected pseudocyesis cases, with primary care physicians serving as essential coordinators of multidisciplinary care. 

Discussion 
This case demonstrates the complexity of diagnosing and managing pseudocyesis, particularly in patients with significant medical histories. The rarity of this condition and the absence of standardized treatment protocols emphasize the critical need for interdisciplinary collaboration between primary care providers and psychiatric services. Primary care physicians are uniquely positioned to identify these cases early, coordinate comprehensive care, and ensure treatment continuity. Early recognition and coordinated care can reduce healthcare utilization, minimize unnecessary testing, and improve patient outcomes in these challenging presentations. 



Pseudocyesis versus Delusional Pregnancy in a Young Adult with history of Neuroblastoma

Background
Invasive mucormycosis is a serious fungal infection that predominantly affects immunocompromised individuals, especially those with diabetes mellitus. Its mortality rate can reach up to 96% despite treatment. Rhino-orbital-cerebral involvement is the most common, but cases of cutaneous mucormycosis, especially in immunocompetent patients, are rare. Factors like trauma, IV drug use, and nosocomial infections increase the risk of infection. Necrotizing fasciitis caused by Rhizopus species is extremely rare without conditions such as uncontrolled diabetes or immunosuppressive therapy. Early recognition and aggressive treatment are crucial, as mucormycosis leads to rapid tissue necrosis, and delayed diagnosis worsens outcomes.
Case Report
A 57-year-old male with schizophrenia and hypertension was found unconscious in a field and brought to the emergency department as a John Doe. Upon admission, he was hyperthermic (107.2°F) and tachycardic, requiring cardioversion. His condition quickly deteriorated into multiorgan dysfunction, including rhabdomyolysis-induced acute kidney injury, disseminated intravascular coagulation (DIC), and necrotizing fasciitis. Blood cultures revealed Pseudomonas, Stenotrophomonas, Enterococcus faecalis, Micrococcus luteus, and Zygomycetes, and histopathology confirmed mucormycosis.
The patient's presentation was complicated by psychiatric instability, as he had not been taking his prescribed medications and was displaying erratic behavior prior to his disappearance. He was intubated, given vasopressors, and started on broad-spectrum antibiotics. As cultures returned, antifungal therapy with Amphotericin B was initiated, later transitioned to isavuconazole. He required multiple rounds of surgical debridement for necrotic tissue, with the largest wound measuring 28 x 18 x 10 cm. His kidney function initially worsened, necessitating hemodialysis, but improved with supportive measures. He also experienced significant difficulty with oral intake, requiring enteral feeding via a PEG tube.
Discussion
This case presents a rare and complex presentation of cutaneous mucormycosis, exacerbated by prolonged environmental exposure, psychiatric illness, and bacterial co-infection. While mucormycosis is often associated with immunocompromised patients, especially those with diabetes, this case shows that other factors, such as trauma and bacterial infection, can also facilitate fungal colonization. The patient’s hyperthermia, rhabdomyolysis, and tissue breakdown provided conditions favorable for fungal growth. Mucormycosis is difficult to diagnose early, especially when bacterial infections mask its characteristic tissue necrosis. This case underscores the importance of early suspicion, rapid antifungal treatment, and a multidisciplinary approach to managing such complex infections. Aggressive debridement and antifungal therapy were key to the patient’s eventual recovery.

Acute Invasive Mucormycosis (Zygomaticus) in Schizophrenic Patient: A Case Report and Literature Review

Background: Developmental facial paralysis (DFP) is a rare congenital condition most often associated with syndromes such as Möbius, CHARGE, and Goldenhar. Isolated cases without syndromic features are uncommon. Chiari I malformation (CM-I), characterized by herniation of the cerebellar tonsils through the foramen magnum, is a structural anomaly of the posterior fossa. To our knowledge, there are no published reports of DFP co-occurring with CM-I. However, posterior fossa abnormalities may hypothetically interfere with cranial nerve development if they
arise during critical periods of neurodevelopment.
Case Presentation: A 37-year-old woman with a lifelong history of right-sided lower motor neuron facial palsy presented with six months of occipital headaches, intermittent neck pain, vertigo, and nausea. Her medical history included idiopathic seizures and chronic gastritis. Neurologic examination revealed an isolated, non-progressive facial palsy without other cranial nerve deficits. Brain MRI demonstrated a 12 mm descent of the cerebellar tonsils below the foramen magnum, consistent with CM-I. She underwent posterior fossa decompression with
suboccipital craniectomy and C1 laminectomy. Postoperative follow-up showed resolution of her new symptoms, but the facial paralysis persisted.
Discussion: This case suggests a possible link between CM-I and isolated DFP. While her facial palsy was congenital and remained unchanged after decompression, the presence of CM-I raises the question of whether altered posterior fossa dynamics may have influenced facial nerve development in utero. Potential mechanisms include mass effect affecting the facial nucleus, cerebrospinal fluid flow disruption, or ischemia due to compromised distal paramedian perforators of the basilar artery. These changes may impair neurogenesis or lead to irreversible nerve injury if present during key embryologic windows. This report highlights a rare clinical
overlap and invites further investigation into how structural posterior fossa anomalies might contribute to isolated cranial nerve deficits.


Posterior Fossa Constraints in a Case of Developmental Facial Palsy with Chiari I Malformation

Background:
The spectrum of vascular access-site complications following cardiac catheterization can vary widely in severity, ranging from simple to complex, and can contribute to significant morbidity with a high economic burden and healthcare costs.
Aim:
The case presentation aimed to describe a post-discharge delayed complication (acute limb ischemia) of cardiac catheterization due to noncalcified plaque.
Case Presentation:
A 58-year-old male with a history of coronary artery disease, diabetes mellitus, and hyperlipidemia underwent cardiac catheterization status-post angioplasty to the right coronary artery via right-femoral artery access. The patient was discharged home post-procedure; however, 8 hours later, he developed a sudden-onset cold foot, worsening numbness, and tingling sensation in his right extremity that prompted him to present to the ER. Physical examination was notable for cold skin in his right leg with diminished dorsalis pedis and popliteal pulses, and a mild loss of “touch sensation” below the level of the knee. The patient was staged “IIa” on the Rutherford Acute Limb Ischemia score. Vitals and labs were within normal limits. CT Angiogram revealed focal high-grade stenosis in the right common femoral artery at the site of a recent arterial puncture from cardiac catheterization. This was likely secondary to nonocclusive, noncalcified plaque that has been disrupted from recent instrumentation. A Heparin drip was initiated and the patient underwent emergent revascularization with a diagnostic angiogram and balloon angioplasty of the right common femoral artery with the placement of a 27mm stent. A completion angiogram showed the resolution of the high-grade stenosis with excellent flow through the profound and superficial femoral artery. 
Discussion:
The risk of access-site complications following cardiac catheterization, although quite low, is increased with the femoral artery, with an incidence estimated to be as high as 17%. Bleeding and bruising are common issues, but blood clots are rare and usually happen due to the breaking of plaque in the arteries or damage to the plaque that leads to a clot. When the severity of limb ischemia is threatening, immediate anticoagulation followed by surgical revascularization is the most appropriate intervention. Thrombosis at the access site of cardiac catheterization can cause critical limb ischemia, particularly with the femoral artery, thus highlighting the need for careful postoperative follow-up. 


Acute Limb Ischemia from Catheter-Induced Plaque Rupture - A Case Report

Background 
People experiencing homelessness (PEH) face dramatically higher traffic collision exposure than housed individuals, with limited published quantification of this disparity. Hit-and-run crashes involving unhoused victims represent a critical knowledge gap, as driver behavior and emergency response patterns remain poorly understood. This pilot study aims to: (1) test whether PEH in Sacramento County have elevated pedestrian hit-and-run (PHAR) fatality risk, and (2) compare injury severity patterns between housed and unhoused victims using postmortem medical examinations. 

Methods 
This mixed-methods retrospective study analyzed Sacramento County pedestrian fatalities using 2020-2024 data for population-level analysis, and January 2024-March 2025 cases for forensic sub-analysis to balance epidemiological rigor with policy-relevant timeliness. 

We calculated relative risk (RR) and population attributable risk percentages (PARP) using Census data, Sacramento Coroner website data, and Sacramento Steps Forward point-in-time homelessness estimates. For injury severity subgroup analysis, we obtained autopsy reports (n = 14) via public records request and applied the Forensic Injury Severity Score Template (FISST), converting descriptive findings to numerical scores, as described by Kim et al (2023). Housing and hit-and-run status was determined through coroner investigation. Given small sample size, we employed descriptive statistics with bootstrapped 95% confidence intervals (CI) and computed Cohen's d (CD) to assess differences between group means. 

Results 
Population-level analysis from 2020-2024 revealed PEH face substantially elevated pedestrian fatality risk compared to housed counterparts (RR 92.2, 95% CI 72.57-117.10), with even higher PHAR fatality risk (RR 113.6, 95% CI 70.62-182.80). PEH were overrepresented in PHAR deaths, accounting for over a third of cases despite representing <1% of the population (PARP = 34.4%). 

FISST scoring analysis of 14 autopsies (seven unhoused, six housed, one excluded outlier: Grubbs’ G= 2.57) demonstrated unhoused victims sustained slightly more severe injuries overall (mean FISST 103.7 vs 84.5, CD= -0.45) with significantly worse chest trauma (mean 34.0 vs 18.0, CD= -1.09) and negligible differences in head/neurological trauma (mean 38.7 vs 37.9, CD = 0.03). Available toxicology analysis was positive in 89% of PHAR victims, with amphetamines detected in three-quarters of those cases. Hit-and-run crashes occurred exclusively at night, with 54.5% of PEH involved in PHAR compared to 33.3% of housed victims. Among all PHAR, 81.8% died within one hour versus 33.3% of non-hit-and-runs. 

Conclusion 
These findings support implementing targeted safety interventions in areas with known unhoused populations, integrating substance harm reduction programs and enhancing nighttime pedestrian safety measures to address Sacramento’s 114-fold disparity in pedestrian hit-and-run fatality risk for PEH. 


At the Intersection of Hit-and-Runs and Homelessness: Pilot Risk Analysis and Postmortem Case Series

Hypothesis:
Type 2 Diabetes dietary management and recipes that account for Hispanic palates can increase compliance especially among youth. 

Background:
Type 2 diabetes has disproportionately affected Hispanic youth who have higher rates of type 2 diabetes and obesity than any other ethnic group in the United States. Cultural food preferences and unhealthy dietary intake contribute to increasing diabetes rates among Hispanic American youth; however, there is a need to better understand the cultural factors affecting dietary diabetes prevention and management among Hispanic youth.

Methods:
The project has 3 phases in progress, for Phase 1, a systematic review is underway examine the cultural factors affecting dietary management of type 2 diabetes among Hispanic Americans. Search terms were defined using PICO and primary research articles were searched in PubMed, Scopus, CINHAL and Psych Info with an emphasis on acculturation, Western diets, assimilation, and type 2 diabetes. Articles retrieved were filtered on inclusion and exclusion criteria, which will dictate the final number of articles used in the review.
Phase 2 involves the development of a cookbook based on recommendations from the American Diabetes Association and the CDC with an emphasis on a youth-catered Hispanic palate. Phase 3 will involve recruiting participants to evaluate the palatability, attitudes and acceptance of the modified recipes in comparison to traditionally prepared meals. Differences between the preferences of meal-types and the likelihood to modify dietary intake to diabetes-friendly recipes will be assessed. 

Preliminary Results/Conclusions:
Phase I: The preliminary results of the review suggest that the extent to which Hispanic individuals were assimilated into U.S. society affects one’s dietary habits and thus their compliance with traditional diabetes management. Over 713 abstracts are currently being screened.

Phase II: 20 recipes have been developed for breakfast, lunch, dinner, dessert, and traditional Hispanic meals with nutrition facts, preparation time, and costs included for consideration of time and financial restraints.

Phase III: The palatability evaluation is currently pending IRB approval.


Improving Type 2 Diabetes Dietary Prevention and Management Among Hispanic Children and Adolescents

Background

Pseudomyxoma peritonei (PMP) is a rare, clinically aggressive neoplasm characterized by mucinous peritoneal implants, with an annual incidence of 1-2 cases per million. Prognosis is dominated by histopathologic subtype. Without intervention, the median survival rate is 3.2 years, with intestinal failure being the predominant cause of death. Diagnostic challenges persist due to non-specific symptomatology and insidious onset, compounded by frequent misclassification in up to 38% of cases.

Case Presentation

A 48-year-old male with a 2015 appendectomy for low-grade mucinous carcinoma (LAMN), also named disseminated peritoneal adenomucinosis (DPAM). Developed voluminous ascites eight years later. Peritoneal cytology suggested metastatic colorectal adenocarcinoma (IHC: CK20+/CDX2+/SATB2+). CT confirmed isolated peritoneal carcinomatosis with elevated CEA (186 ng/mL). Histopathology reclassified the disease as Grade 1 PMP (DPAM subtype). Neoadjuvant FOLFOX (6 cycles) yielded no response (RECIST 1.1), precluding cytoreduction. Transition to FOLFIRI achieved symptomatic resolution, CEA normalization (8.2 ng/mL), and 9-month radiographic stability.

Discussion

Initial misclassification as colorectal adenocarcinoma (or ovarian cancer) underscores pseudomyxoma peritonei's (PMP) diagnostic complexity. Reported in similar cases as this one. While CK20/CDX2/SATB2 positivity overlaps with gastrointestinal malignancies, PMP's distinct molecular signature (84% KRAS mutations vs. 45% in colorectal cancer) and indolent clinical behavior mandate expert pathology review using Ronnett criteria to prevent therapeutic misdirection. Additionally, molecular profiling (KRAS/MGMT status) resolves diagnostic ambiguity 

Late Recurrence & Surveillance: This recurrence at 8 years exceeds standard 5-year surveillance for LAMN, aligning with evidence that 2–3% of DPAM cases recur >10 years post-resection. This Risk correlates with initial perforation and positive surgical margins at initial resection. Symptoms manifesting at 8 years underscore the need for extended monitoring (CT + CEA/CA19-9 beyond 5 years), which challenges NCCN guidelines that recommend a 5-year follow-up.

Prognostic & Therapeutic Implications: Histologic grade is the dominant survival predictor, with peritoneal mucinous carcinomatosis (PMCA) conferring 4.2× higher mortality risk vs. DPAM. While Completeness of Cytoreduction (CCR)-0/1 resection + Hyperthermic Intraperitoneal Chemotherapy (HIPEC) is ideal, systemic therapy (e.g., FOLFIRI) achieves durable disease control in CCR-unfit patients, preserving quality of life in 68% of long-term survivors 

The observed FOLFOX resistance but FOLFIRI response aligns with mucinous tumor biology. Oxaliplatin-based regimens demonstrate limited efficacy in PMP (objective response rate [ORR]: 20–30%), whereas irinotecan achieves 60–70% disease control through topoisomerase inhibition and anti-angiogenic effects. For unresectable DPAM, FOLFIRI represents a validated alternative, with a median progression-free survival (PFS) of 8.1 months.

This research redefines PMP as a paradigm-shifting model, where extended surveillance prevents missed recurrences, molecular stratification overcomes diagnostic mimicry, and tailored chemotherapy rescues surgically frail patients.


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