Beamer, Staci E.

Summary Caustic esophageal injury can cause severe morbidity and mortality. Despite the need for emergent treatment, individual experience in diagnosis and management can be limited. Computed tomography (CT) has emerged as a promising non-invasive modality for assessing injury severity, but the clinical utility of both CT and endoscopy should be investigated. A systematic review was conducted following PRISMA guidelines. A comprehensive search of the PubMed database identified relevant articles published from January 1, 2000 to December 31, 2023. Inclusion criteria encompassed studies investigating the use of CT and/or endoscopy in diagnosing and managing caustic esophageal injury. Twelve articles were selected from a pool of 931 studies. Findings suggested that CT was superior in diagnostic capability to endoscopy in high-grade injury and stricture formation, but less so for low grade injuries. Diagnostic algorithms incorporating imaging with laboratory studies have emerged in the literature, which are promising pending additional validation. CT can serve as a valuable, non-invasive tool in the initial evaluation of caustic esophageal injury and is postulated to accurately predict both the need for emergent surgery and the risk of stricture formation. However, CT should not replace but rather complement the use of endoscopy to comprehensively evaluate these potentially highly morbid situations.

AbstractBackgroundThere is a knowledge gap regarding lobar versus sublobar resection for atypical carcinoid (AC) of the lung. As such, the authors sought to understand and analyze the outcomes of sublobar resection versus lobectomy in this patient population.MethodsA retrospective analysis using the National Cancer Database was performed to compare overall survival (OS) between patients treated with lobectomy and patients treated with sublobar resection for AC of the lung between the years 2004 and 2016. Patient characteristics were compared with χ2 tests. The Kaplan–Meier method was used to estimate OS distributions, and the log‐rank test was used to compare distributions by treatment strategy. A multivariable Cox regression model was used to assess associations between the treatment strategy and OS. A propensity score matching method was also implemented to further eliminate treatment selection bias in the study sample.ResultsThe database identified 669 patients with T1–T4 and N0–N3 lung ACs that were surgically resected. Unadjusted Kaplan–Meier survival curves did not demonstrate an OS difference between lobectomy and sublobar resection (p = .094). After propensity score matching, curves demonstrated a numerical improvement in OS with lobectomy; however, it was not statistically significant (p = .5). In a subgroup analysis, lobectomy and node‐negative disease were associated with the best OS, whereas sublobar resection and node‐positive disease were associated with the worst OS (p < .0001). Nodal involvement was associated with worse survival, regardless of surgical treatment (p < .0001).ConclusionsIn patients with T1–T4 and N0–N3 ACs of the lung, lobectomy was not associated with an improvement in OS in comparison with sublobar resection.

Abstract Background Lung cancer screening programs have increased the detection of early-stage lung cancer. High-resolution computed tomography can detect small, low-density pulmonary nodules, or ground-glass opacities. Obtaining a tissue diagnosis can be challenging, often necessitating surgical diagnosis. Preoperative localization and intraoperative fluoroscopy are valuable tools to guide resections for small pulmonary nodules. Case Description We present three cases using intraoperative fluoroscopy and Faxitron Bioptics that enhanced our certainty of resection of nonpalpable nodules. Conclusion We support the use of intraoperative fluoroscopy with the unique addition of Faxitron BioVision as safe and reliable methods to enhance the certainty of resection.

Abstract Purpose: This phase Ib/2 trial investigated pembrolizumab-containing trimodality therapy in patients with gastroesophageal junction (GEJ) adenocarcinoma. Patients and Methods: Patients with GEJ adenocarcinoma (cT1–3NanyM0) received neoadjuvant pembrolizumab-containing chemoradiation (CROSS regimen) followed by surgical resection and adjuvant pembrolizumab. The primary endpoints were tolerability in the first 16 patients and pathologic complete response [pCR (ypT0N0)]. Secondary endpoints included progression-free survival (PFS) and overall survival (OS). An independent propensity-score-matched cohort (treated with CROSS without immunotherapy) was used for comparison. Exploratory analyses included immune biomarkers in the tumor microenvironment (TME) and plasma. Results: We enrolled 31 eligible patients, of whom 29 received all expected doses of neoadjuvant pembrolizumab and 28 underwent R0 resection. Safety endpoints were met. The primary efficacy endpoint was not met [7/31 (22.6%) achieved pCR]. Patients with high [i.e., combined positive score (CPS) ≥ 10] baseline expression of programmed death (PD)-L1 in the TME had a significantly higher pCR rate than those with low expression [50.0% (4/8) vs. 13.6% (3/22); P = 0.046]. Patients with high PD-L1 expression also experienced longer PFS and OS than propensity-score-matched patients. Among trial patients with PD-L1 CPS &lt; 10, unprespecified analysis explored whether extracellular vesicles (EV) could identify further responders: an elevated plasma level of PD-L1–expressing EVs was significantly associated with higher pCR. Conclusions: Adding pembrolizumab to trimodality therapy showed acceptable tolerability but did not meet the pre-specified pCR endpoint. Exploratory analyses suggested that high PD-L1 expression in the TME and/or on EVs may identify patients most likely to achieve tumor response.

Abstract Doege Potter syndrome is a rare condition causing non-islet cell paraneoplastic hypoglycaemia associated with fibrous tumours, which can be both benign and malignant. The vast majority are solitary and located within the chest. Non-islet cell tumour-induced hypoglycaemia, as in Doege Potter syndrome, is quite rare and occurs around 4 times less often than islet cell-associated paraneoplastic hypoglycaemia. We present a case of Doege Potter syndrome with severe hypoglycaemia in conjunction with multiple recurrent fibrous tumours of the lung and pleura.

159 Background: Intensity-modulated proton therapy (IMPT) with small spot size has the potential to reduce dose to normal tissues but also introduces new confounding factors such as setup uncertainty, range uncertainty, and interplay effects due to breathing motion. We investigated plan quality and robustness of IMPT with small spot size for distal esophageal adenocarcinoma (DEA). Methods: 19 patients with DEA treated by IMPT were retrospectively evaluated. Spot sizes ranged from 2 to 6mm, with spot spacing of 5mm. All plans were generated using a commercial treatment planning system. In-house-developed dose-evaluation software modeled time-dependent spot delivery to incorporate interplay effects. Dose-volume-histogram (DVH) indices were used to evaluate plan quality and robustness was evaluated using the DVH band method. Results: For plan quality, median values of clinical target volume D95% and D5%-D95% (normalized to the prescribed doses), total lung mean dose, heart mean dose, and cord Dmax were 1.014, 0.035, 3.82Gy[RBE], 7.73Gy[RBE], 39.16Gy[RBE], respectively. For plan robustness, median band widths of the aforementioned DVH indices were 0.018, 0.048, 0.60Gy[RBE], 4.17Gy[RBE], and 2.36Gy[RBE], respectively. For interplay effects, median values of the aforementioned DVH indices were 0.99, 0.061, 4.07Gy[RBE], 7.87Gy[RBE], and 39.66Gy[RBE], respectively. Seven patients underwent esophagectomy after neoadjuvant chemoradiation, and five, three, and one of them achieved downstaging, near complete response, and pathologic complete response, respectively; R0 resection was achieved in all cases. For all patients, acute side effects were mostly limited to grades 1-2 only. The only grade 3 adverse events were related to feeding tube placement (8 patients); there were no RT-induced pneumonitis or other lung-related toxicities. Conclusions: IMPT plans with small spot size for DEA have good target dose coverage, homogeneity and normal tissue protection. Treatment plans are also robust to uncertainties and interplay effects. Early clinical results demonstrate low acute toxicity and encouraging clinical and pathologic response.

e15567 Background: Esophageal adenocarcinoma (EAC) prognosis is poor and there is a need to identify patients that benefit most from neoadjuvant therapy. To examine the association of various biomarkers with clinical outcomes in neoadjuvant treatment of EAC, we retrospectively evaluated the biomarker expression (TS, ERCC1, TOPO1, PD-L1, PD-1) in patient matched formalin-fixed paraffin-embedded (FFPE) tumor samples. Methods: Immunohistochemistry of TS (TS106/4H4B1) , ERCC1 (Ab. 8F1), TOPO1 (1D6), PD-L1 (both 22c3 and SP142), PD-1 (NAT105), and chromogenic in-situ hybridization (CISH) of Her2 were performed on FFPE samples from 35 patients across 2 institutions at time of EAC diagnosis and after treatment when available. Retrospective clinical data and survival (5/2006-1/2016) was analyzed with a mean follow up of 110 months (range 22-306). Results: Overexpression (pre/post-treatment) of TS (60%/54%), ERCC1 (69%/16%), TOPO1 (74%/50%), PD-1 (54%/63%), PD-L1 (SP142) (2.9%/4%), PD-L1 (22c3) (0%/4%) and amplification of Her2 (18%/23%) were observed. Pretreatment observed PD-L1 levels were lower in our study (3%) when compared to other studies in EAC specimens (35%). Immunohistochemistry and changes observed after chemoradiation are reviewed in Table. No markers had significant correlation with prognosis however TS negative expression showed a non-significant (p=0.15) trend towards improved survival. Conclusions: Analyzing biomarkers in our neoadjuvant EAC cohort demonstrated a lower than expected PD-L1 positivity. In the largest cohort, to our knowledge, of patient matched FFPE tumor samples, we did not observe a statistically significant association between TS, ERCC1, TOPO1, PD-L1, or PD-1 with improved clinical outcomes. [Table: see text]

e15563 Background: Expression of thymidylate synthase (TS), a target of fluoropyrimidine-based (5-FU) chemotherapy, has prognostic value in colorectal adenocarcinoma. Its value as a biomarker in treatment of esophageal adenocarcinoma (EAC) is unknown. With widespread adoption of CROSS trial protocol for treatment of EAC, 5-FU is frequently omitted from regimens. We retrospectively analyzed the association between TS protein expression and clinical outcomes in EAC. Methods: TS expression levels were measured by immunohistochemistry in formalin-fixed paraffin-embedded specimens from 35 primary EAC patients from 2 institutions (range 5/2006-1/2016); at time of diagnosis and surgical resection (33 neoadjuvant chemoradiation and 2 surgery alone). TS expression higher than 1+, 5% was read as positive. Mean follow up was 1323 days (range 263-3677). TS expression correlated with treatment response and survival in patients treated with and without 5-FU therapy (log-rank test, Kaplan-Meier method). Results: In the cohort of 35 patients, 21 patients (60%) had pretreatment positive TS expression. Overall survival (OS) for TS negative patients was 1216 days versus 974 days for TS positive (p = 0.15). In the 23 patients treated with 5-FU, TS-negative patients had a trend towards longer overall survival compared to TS-positive patients, mean OS (1272 days versus 743 days, p = 0.08). In the group of 12 patients not treated with 5-FU, 2 patients showed negative TS staining. Neoadjuvant chemoradiation was performed in 33/35 patients. Downstaging was observed in 69% (9/13) of patients with negative pre-treatment TS levels versus 55% (11/20) in pre-treatment TS positive patients (p = 0.48). In 23 patients treated with 5FU, 9/12 (75%) were downstaged in the TS-negative cohort versus 6/11 (45%) in the TS-positive cohort (p = 0.21). In the 5FU treatment group, complete response was seen in 2 patients with negative TS staining. Conclusions: Low TS expression in EAC patients trended towards improved survival and tumor downstaging, particularly in patients treated with neoadjuvant 5-FU and platinum based therapy. Prospective data and greater patient numbers may be necessary to demonstrate statistical significance.