Thompson, Scott M.

Abstract Prostate-specific membrane antigen (PSMA) is highly expressed in tumor-associated neovasculature in hepatocellular carcinoma (HCC), highlighting its promise as a theranostic target. This prospective study aimed to evaluate the utility of novel biomarkers derived from PSMA positron emission tomography computed tomography (PET/CT) to assess treatment response in advanced HCC patients (pts) receiving first line immune checkpoint inhibitors (ICI). Methods: This study (NCT05176223) enrolled unresectable, advanced HCC pts eligible for first-line ICI (atezolizumab/bevacizumab [A/B] or durvalumab/tremelimumab [D/T]) with measurable disease according to RECIST criteria. Primary endpoints: progression-free survival (PFS) per RECIST 1.1 and mRECIST; overall survival (OS); and best overall response. The survival distribution was estimated using the Kaplan-Meier method. Observed agreement is defined as the proportion of pts whose responses, as classified by PET/CT or CT, were concordant. Weighted kappa and Cohen’s kappa were used to quantify the strength of agreement between PET/CT and CT. Pts completed up to five 68Ga-PSMA PET/CT scans and blood collections. Results: Twenty-six pts were enrolled (25 evaluable) between Oct 2022 and Nov 2024. Median follow up was 22.1 months (m) (Q1, Q3: 14.5-23.7). Median age 68 yrs, 72% male, 88% White, 68% Child-Pugh [CP] A, 32% CP B, 32% Barcelona Clinic Liver Cancer [BCLC] stage B, 68% BCLC stage C, 36% with microvascular invasion; 56% received A/B and 40% received D/T treatment. PSMA was positive in 96% of pts at baseline with median SUVmax 14.3 (range 5.1-40.5) and median background liver SUVmax 3.9 (range 2.1-6.8). Median (95%CI) PFS was 5.6 m (4.6-12.5) by both RECIST and mRECIST. Median (95%CI) OS was 18.6 m (7.2-not estimable), with 56% deceased. The observed agreement between PET/CT adapted PERCIST criteria compared to RECIST and mRECIST in determining the best response was 46% and 50% and weighted kappa of 0.63 (95% CI: 0.37-0.90) and 0.66 (0.41-0.92), respectively. Observed agreement between PERCIST compared to RECIST and mRECIST for responders’ assessment was 67% and 71% with Cohen’s kappa of 0.36 (0.03-0.68) and 0.43 (0.11-0.76), respectively. Conclusion: In this cohort, PSMA PET/CT avidity was observed in all but one pt with advanced HCC, each demonstrating moderate to high SUVmax values. Median OS and PFS were consistent with outcomes reported in clinical trials. Response assessment using 68Ga-PSMA PET/CT according to PERCIST criteria showed good concordance with both RECIST and mRECIST standards. Analysis of immune biomarkers is ongoing. Citation Format: Nguyen H. Tran, Jacob Hirdler, Ajith Antony, Jacob Teske, Sudhakar K. Venkatesh, Amit Mahipal, Michael S. Torbenson, Scott M. Thompson, Thor R. Halfdanarson, Zhaohui Jin, Lionel Aurelien Kankeu Fonkoua, Leslie A. Washburn, Alexander Revzin, Haidong Dong, Robert R. Mcwilliams, Aminah Jatoi, Hani M. Babiker, Mitesh J. Borad, Tanios Bekaii-Saab, Gregory J. Gores, Lewis R. Roberts, Geoffrey B. Johnson, Ajit H. Goenka. Prospective evaluation of 68Ga-PSMA PET imaging in advanced hepatocellular carcinoma patients undergoing first line immunotherapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2026; Part 1 (Regular Abstracts); 2026 Apr 17-22; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2026;86(7 Suppl):Abstract nr 2611.

Percutaneous gastrostomy tube insertion in post Roux-en-Y patients can be challenging due to decompression of the excluded stomach and its discontinuity with the proximal enteric tract. Presented here is a 65-year-old woman status post Roux-en-Y gastric bypass who required gastrostomy tube placement for enteral feeding. The remnant stomach collapsed, and direct percutaneous gastric access was not possible for insufflation. To facilitate insufflation, computed tomography (CT) was used to access the duodenal bulb. This duodenal access was used to insufflate the stomach in a retrograde fashion which created a safe percutaneous window for gastrostomy tube placement into the remnant stomach. The technique described in this study can be a useful tool in patients with difficult to access remnant stomachs. Utilizing either direct or transhepatic access to the duodenum with ultrasound or CT guidance for remnant stomach insufflation can facilitate gastrostomy tube placement in challenging cases.

The purpose of this study is to investigate the potential of using ultrasound gel to mitigate the risks of skin burn at the insertion site during microwave ablation (MWA) using non-actively cooled applicators. Ex vivo experiments in porcine tissue were conducted using two identical MWA systems. Five MWA scenarios were tested at different applicator insertion depths with an ultrasound gel layer applied at the applicator insertion sites: 8 cm insertion depth with and without 4 cm thick gel, 10 cm insertion depth with and without 2 cm thick gel, and 12 cm insertion depth without gel (reference). In all experiments, temperature elevations at the applicator insertion site on the tissue surface were recorded using thermal sensors in all experiments during 10-min MWA. The application of ultrasound gel and increasing applicator insertion depths resulted in measurable reductions in temperature elevations at the applicator insertion sites. For an insertion depth of 8 cm, the temperature elevations were 39.9 ± 4.7°C and 23.2±6.5°C without and with gel, respectively (P < 0.001). For an insertion depth of 10 cm, the temperature elevations were 20.8 ± 1.5°C and 14.4 ± 1.5°C without and with gel, respectively (P < 0.001). The maximal temperature elevations corresponding to an 8 cm insertion depth with gel were comparable with those corresponding to a 10 cm insertion depth without gel. Similarly, the maximal temperature elevations (12.2 ± 1.8°C) corresponding to 12 cm insertion depth without gel were comparable to those corresponding to 10 cm insertion depth with gel. Applying ultrasound gel at the applicator insertion site can significantly reduce temperature elevations at the tissue surface during MWA procedures.

AbstractObjectiveThe objective of this study was to evaluate the role of adrenal venous sampling (AVS) in guiding the management of patients with corticotropin (ACTH)‐independent glucocorticoid secretory autonomy and bilateral adrenal masses.Design and PatientsA cohort with 25 patients underwent AVS and surgical management.MeasurementsCortisol was measured from the adrenal veins (AVs) and inferior vena cava (IVC). AV/IVC cortisol ratio and cortisol lateralization ratio (CLR) (dominant AV cortisol concentration divided by the nondominant AV cortisol concentration) were calculated. Posthoc receiver‐operating characteristic curves were generated to determine the specificity of revised AV/IVC cortisol ratio and CLR in differentiating unilateral from bilateral disease.ResultsPatients underwent unilateral (n = 21) or bilateral (n = 4) adrenalectomy. The mean AV/IVC cortisol ratio for unilateral adrenalectomy was 12.1 ± 9.6 (dominant) and 4.7 ± 3.8 (contralateral) with a mean CLR of 3.6 ± 3.5. The mean AV/IVC cortisol ratio for bilateral adrenalectomy was 7.5 ± 2.1, with a mean CLR of 1.1 ± 0.6. At a mean follow‐up of 22 months, one patient who underwent unilateral adrenalectomy for the predicted bilateral disease developed recurrent mild autonomous cortisol secretion. Posthoc analyses demonstrated a specificity of 95%–100% for unilateral disease with AV/IVC cortisol ratio >9 for one side, <2.0 for the opposite side and a CLR > 2.3. The specificity was 80%–90% for bilateral disease with AV/IVC cortisol ratio >5.1 bilaterally and a CLR < 1.1.ConclusionsAmong patients with bilateral adrenal masses and ACTH‐independent autonomous cortisol secretion, AVS can distinguish between unilateral and bilateral disease with high specificity and may guide surgical management.

Patients with hereditary hemorrhagic telangiectasia (HHT) have arteriovenous malformations (AVMs) with genetic mutations involving the activin-A receptor like type 1 ( ACVRL1 or ALK1 ) and endoglin ( ENG ). Recent studies have shown that Neuropilin-1 (NRP-1) inhibits ALK1. We investigated the expression of NRP-1 in livers of patients with HHT and found that there was a significant reduction in NRP-1 in perivascular smooth muscle cells (SMCs). We used Nrp1 SM22KO mice ( Nrp1 was ablated in SMCs) and found hemorrhage, increased immune cell infiltration with a decrease in SMCs, and pericyte lining in lungs and liver in adult mice. Histologic examination revealed lung arteriovenous fistulas (AVFs) with enlarged liver vessels. Evaluation of the retina vessels at P5 from Nrp1 SM22KO mice demonstrated dilated capillaries with a reduction of pericytes. In inflow artery of surgical AVFs from the Nrp1 SM22KO versus WT mice , there was a significant decrease in Tgfb1 , Eng , and Alk1 expression and phosphorylated SMAD1/5/8 (pSMAD1/5/8), with an increase in apoptosis. TGF-β1–stimulated aortic SMCs from Nrp1 SM22KO versus WT mice have decreased pSMAD1/5/8 and increased apoptosis. Coimmunoprecipitation experiments revealed that NRP-1 interacts with ALK1 and ENG in SMCs. In summary, NRP-1 deletion in SMCs leads to reduced ALK1, ENG, and pSMAD1/5/8 signaling and reduced cell death associated with AVM formation.

Medical drains frequently become obstructed requiring removal or re-intervention. Currently, there is no widely accepted practice for maintaining drain patency. A simple device to remove obstructions from medical drains may have significant benefit. We manufactured a prototype drain clot extractor (DCE) for extracting obstructions. Fresh nonanticoagulated swine blood was instilled within drainage tubes of 16, 20, and 32 French (n = 2 for each size) to generate a 4 cm blood clot. The operator was then equipped with a 0.035 in. guidewire (GW) and given 2.5 min to attempt removal while blinded. Similarly, the operator was equipped with the DCE. Volumes removed were determined by volume displacement and by drain size and method of removal. Comparison of DCE to GW by analysis of variance and means comparison using Tukey were used for statistical analysis. The DCE facilitated mechanical removal of obstructions for 16, 20, and 32 French drainage tubes. Volumes removed: 16 French (GW mean 10% volume, DCE mean 70% volume p = 0.02); 20 French (GW mean 12.5% volume, DCE mean 75% volume p = 0.01); 32 French (GW mean 37.5% volume, DCE mean 100% volume p = 0.01). DCE volume removal had no dependence on drain size (p > 0.05). This device may have utility for reducing morbidity from early drain discontinuation or replacement. Further in vivo and clinical studies are needed to determine the safety, feasibility, and efficacy of this device as tool for removing medical drainage obstructions.

AbstractBackgroundIn patients with persistent (P‐PHPT) or recurrent (R‐PHPT) primary hyperparathyroidism, preoperative localization is important. Selective parathyroid hormone venous sampling (sPVS) is an invasive technique that can be used to regionalize and/or lateralize the source of PHPT when noninvasive imaging studies are nonlocalizing. The aim of the present study was to assess the role of sPVS in the preoperative evaluation of patients with P‐PHPT or R‐PHPT and negative, equivocal, or discordant noninvasive imaging localization.MethodsAfter IRB‐approval a retrospective review of all patients with P‐PHPT or R‐PHPT and nonlocalizing noninvasive imaging that underwent sPVS from 2000 to 2014 was performed. The location of the source of PHPT at sPVS was predicted by a parathyroid hormone (PTH) gradient and compared to the surgical, pathology, and biochemical follow‐up data as the gold standard. Sensitivity and positive predictive value (PPV) were calculated.ResultsOf 30 patients who underwent sPVS, 12 patients did not undergo surgical exploration due to negative or non‐localizing PTH gradient (n = 8) or opted for medical management (n = 4). Of the 18 patients who underwent surgical exploration, 17 (94 %) had a positive PTH gradient and pathologic parathyroid tissue identified at surgery. Sensitivity and PPV of sPVS were 93 and 77 %, respectively, for all surgical cases, 86 and 60.0 % for cervical cases (n = 11), and 100 and 100 % for mediastinal cases (n = 7). Sixteen patients (89 %) were surgically cured.ConclusionsIn patients with P‐PHPT or R‐PHPT and nonlocalizing imaging studies, sPVS is a sensitive test for localizing the source of PHPT when a positive PTH gradient is present.