Repeat CT Scan Research Articles

Comparing three-dimensional zero echo time (3D-ZTE) lung MRI and chest CT in the evaluation of systemic sclerosis-related interstitial lung disease.

Systemic sclerosis (SSc) is a chronic disease that can cause interstitial lung disease (ILD), a poor prognostic factor in SSc patients. Given the concerns over radiation exposure from repeated CT scans, there is a growing interest in exploring radiation-free imaging alternatives like MRI for ILD evaluation. The aim of this study is to assess the efficacy of three-dimensional zero echo time (3D-ZTE) MRI in assessing SSc-related ILD compared to the thin-slice chest CT. This prospective single-center study investigated 65 SSc patients. SSc patients underwent CT, 3D-ZTE lung MRI, and pulmonary function tests (PFTs) within a week. Three independent reviews visually quantified ILD extent on ZTE and CT imaging and the correlation of ILD extent with PFTs was analyzed. Statistical analyses were performed, including the intraclass correlation coefficient (ICC), Kruskal-Wallis tests, Bland-Altmann analysis, and correlation analyses between imaging results and PFTs. ILD was detected in 45 patients via CT. 3D-ZTE MRI identified ILD in 41 (91.1%) of these cases, demonstrating a strong correlation with CT in assessing ILD severity (r = 0.986, p < 0.001). The median ILD extent scores were 5% for CT and 6% for 3D-ZTE MRI. Interobserver reliability for 3D-ZTE MRI was excellent, with ICC values ranging from 0.853 to 0.969. The analysis also revealed significant negative correlations between ILD extent on ZTE MRI and lung function, particularly FVC. 3D-ZTE lung MRI is a reliable and radiation-free alternative to chest CT for evaluating SSc-related ILD, with a strong correlation in assessing total fibrosis and ground-glass opacities, though limitations remain in detecting fine reticulations and coarseness. Question Can 3D-ZTE MRI replace thin-slice chest CT as a radiation-free method for assessing SSc-related ILD? Findings 3D-ZTE lung MRI showed an excellent agreement with thin-slice CT in evaluating ILD extent in SSc patients (r = 0.986, p < 0.001). Clinical relevance 3D-ZTE lung MRI provides a reliable, radiation-free alternative to CT for assessing ILD extent in SSc patients, ensuring safer longitudinal monitoring and management.

Comparing the Efficacy of Empirical Anti-Infective Therapy and Follow-Up Observation for Newly Diagnosed Pulmonary Ground-Glass Nodules With Suspected Inflammatory Etiology: A Multicenter Prospective Observational Study Protocol.

The optimal management strategy for newly diagnosed pulmonary ground-glass nodules (GGNs) with suspected inflammatory etiology remains controversial in clinical practice. Empirical anti-inflammatory therapy is commonly used, but its efficacy compared with that of follow-up observation lacks high-quality evidence. Therefore, this study aims to compare the effectiveness of empirical anti-infective therapy and follow-up observation for pulmonary GGNs in real-world settings. This study intends to include 254 participants with newly discovered pulmonary ground-glass opacities (GGOs) suspected to be related to inflammation but without current radiographic features suggestive of malignancy. Antibiotics will be recommended when the doctor considers the GGOs may be infection-related. Upon enrollment, all participants will be assessed with the Self-Rating Anxiety Scale (SAS) and divided into either the intervention or observation group. A repeat CT scan and SAS assessment will be conducted with all participants after 1 month ( ± 2 weeks) following the initial discovery of the GGOs. The primary outcome is the participants' response rate at the first follow-up CT. The secondary outcome is the GGO response rate and total scores of SAS at 1 month after enrollment. A non-inferiority test will be conducted to compare the outcomes between the two groups. To date, the efficacy and necessity of using antibiotics for GGOs suspected to be inflammatory upon primary CT screening remain controversial. This protocol describes the rationale and methodology to address this unmet clinical need using real-world data, aiming to bridge the gap between clinical guidelines and real-world practice. Trial Registration: ChiCTR2200056975.

CT surveillance for type 1 autoimmune pancreatitis: cumulative radiation dose and diagnostic performance for disease relapse.

Long-term follow-up is essential for type 1 autoimmune pancreatitis (AIP) patients due to high relapse rates. The cumulative radiation dose from repeated CT scans during follow-up should not be ignored. We aim to investigate the cumulative radiation dose in AIP patients undergoing CT surveillance and the diagnostic performance of CT in detecting disease relapse. The diagnostic performance of MRI from a secondary cohort during the same period was also investigated. This retrospective single-institutional study included 247 type 1 AIP patients with one or more follow-up CT scans, and 120 patients with MR follow-ups. Four metrics were utilized to report the radiation dose, including the volume computed tomography dose index, the dose length product, size-specific dose estimate and effective dose. The diagnostic performance for AIP relapse was assessed, taking the final clinical diagnosis in retrospect as the reference standard. With a median 2.3-year follow-up period, AIP patients followed up with CT exhibited a median cumulative radiation dose of 37.5 mSv. 11.3% of patients have accumulated doses exceeding 100 mSv. For the 169 patients followed over a year, 30.8% sustained an average annual radiation dose surpassing 20 mSv. The sensitivity/specificity/accuracy of CT for detecting abdominal organ relapse was 64.1%/99.6%/97.0%. For AIP patients followed up with MRI, the sensitivity for detecting disease relapse was 90.5%. Considering the accumulation of radiation dose in AIP patients and the insufficient sensitivity in detecting disease relapse with CT, safer and more sensitive imaging follow-up strategies should be explored. Question CT, as the primary imaging modality for autoimmune pancreatitis (AIP) follow-up, raises concerns regarding radiation exposure and lacks reported diagnostic performance in detecting AIP relapse. Findings CT in AIP follow-up causes significant cumulative radiation exposure and exhibits insufficient sensitivity in relapse detection. Clinical relevance Type 1 AIP necessitates long-term imaging follow-up, yet current guidelines lack consensus regarding the prioritization of CT or MRI for such follow-up. CT is widely used but has radiation concerns and limited sensitivity, calling for safer, efficient strategies.

A comparative study on automatic treatment planning for online adaptive proton therapy of esophageal cancer: which combination of deformable registration and deep learning planning tools performs the best?

Objective.To demonstrate the feasibility of integrating fully-automated online adaptive proton therapy strategies (OAPT) within a commercially available treatment planning system and underscore what limits their clinical implementation. These strategies leverage existing deformable image registration (DIR) algorithms and state-of-the-art deep learning (DL) networks for organ segmentation and proton dose prediction.Approach.Four OAPT strategies featuring automatic segmentation and robust optimization were evaluated on a cohort of 17 patients, each undergoing a repeat CT scan. (1) DEF-INIT combines deformably registered contours with template-based optimization. (2) DL-INIT, (3) DL-DEF, and (4) DL-DL employ a nnU-Net DL network for organ segmentation and a controlling ROIs-guided DIR algorithm for internal clinical target volume (iCTV) segmentation. DL-INIT uses this segmentation alongside template-based optimization, DL-DEF integrates it with a dose-mimicking (DM) step using a reference deformed dose, and DL-DL merges it with DM on a reference DL-predicted dose. All strategies were evaluated on manual contours and contours used for optimization and compared with manually adapted plans. Key dose volume metrics like iCTV D98% are reported.Main results.iCTV D98% was comparable in manually adapted plans and for all strategies in nominal cases but dropped to 20 Gy in worst-case scenarios for a few patients per strategy, highlighting the need to correct segmentation errors in the target volume. Evaluations on optimization contours showed minimal relative error, with some outliers, particularly in template-based strategies (DEF-INIT and DL-INIT). DL-DEF achieves a good trade-off between speed and dosimetric quality, showing a passing rate (iCTV D98% > 94%) of 90% when evaluated against 2, 4 and 5 mm setup error and of 88% when evaluated against 7 mm setup error. While template-based methods are more rigid, DL-DEF and DL-DL have potential for further enhancements with proper DM algorithm tuning.Significance.Among investigated strategies, DL-DEF and DL-DL demonstrated promising within 10 min OAPT implementation results and significant potential for improvements.

6728 Bilateral Adrenal Hemorrhage: Cause Or Consequence?

Abstract Disclosure: M.N. Rayan: None. R. Horner: None. A. Valenciaga: None. L.E. Ryan: None. Introduction: Before the advent of the CT scan, bilateral adrenal hemorrhage was primarily discovered post-mortem in patients who had succumbed to sepsis, burns, or anticoagulant therapy. Today, non-traumatic hemorrhage is recognized as an infrequent, yet potentially lethal diagnosis causing clinical deterioration in acutely ill patients. Clinical Case: Our patient is a 64-year-old-male with a medical history of Myelodysplastic Syndrome initially presented to an external ED with abdominal pain. CT abdomen revealed hepatomegaly, splenomegaly, and new bilateral adrenal masses—absent in an MRI conducted a year earlier. He was treated conservatively and subsequently discharged. Two weeks later, he returned to the hospital with severe right sided flank pain. His hemoglobin and platelet counts dropped from 11.5 g/dL and 309 K/uL during the previous ED visit to 7.7 g/dL and 80 K/uL, respectively. Additionally, his PT/INR, PTT, fibrinogen, and D-Dimer levels were elevated. A repeat CT scan indicated a significant enlargement of the right adrenal mass, raising suspicion of adrenal hemorrhage. He was appropriately transfused, and a BM biopsy was performed to evaluate for acute transformation of underlying MDS. Cortisol levels were monitored daily for adrenal insufficiency. A complicated hospital course ensued marked by worsening anemia, thrombocytopenia, and coagulopathy, accompanied by high fevers and new-onset atrial fibrillation. Mixing studies showed absence of a factor inhibitor ruling out acquired forms of Hemophilia. Infectious workup including fungal and viral serologies returned negative. A PET scan revealed several small hypermetabolic hypodense liver lesions, and hypermetabolic activity diffusely in the spleen, and adrenal glands leading to suspicion of metastasis. Results of the BM biopsy returned revealing hypercellularity, with aggregates of hemosiderin-laden macrophages replacing the bone marrow space with associated necrosis. Worsening abdominal pain with hematochezia prompted an endoscopy, confirming a diagnosis of metastatic melanoma. Concurrently, seizure activity and altered mentation led to a head CT, revealing new metastatic lesions that confirmed the rapid progression of the disease. Subsequently, the patient was transitioned to comfort care and passed away. Clinical Lesson: It is crucial to review the various causes of adrenal hemorrhage, understand the challenges associated with interpreting adrenal imaging, emphasize the need to monitor adrenal function, and consider the occasional necessity for tissue sampling. In this clinical scenario, metastases with hemorrhage were the most likely etiology. The causes of adrenal hemorrhage are not always apparent; in this presentation, the consequence of the underlying disease state ultimately led to the initial presenting symptom of abdominal pain. Presentation: 6/2/2024

6365 An Atypical Case Of Large Metastatic Pheochromocytoma With Negative Catecholamine Secretion

Abstract Disclosure: D. Caesario: None. J.K. Fernandes: None. Introduction: Pheochromocytomas (PCCs) are rare tumors arising from chromaffin cells of the adrenal medulla. Diagnosis is suggested by clinical presentations and confirmed by biochemical hypersecretion of metanephrines (MN) and catecholamines (CA). We report an atypical case of large metastatic PCC with normal MN and CA. Case Report: A 61-year-old female presented with uncontrolled HTN despite taking amlodipine, losartan, and carvedilol. No other symptoms reported. She had presented 12 years prior with an 8.7 cm left adrenal mass (AdM) that was incidentally found on CT scan, but she was lost to follow-up. Repeat imaging for her current presentation revealed enlargement of left AdM to 15 cm, centrally necrotic, with absolute washout of 63%. There was extensive local regional involvement, including possible invasion of the pancreas; abutment to left kidney, left renal vein, left hepatic lobe, and stomach; encasement and possible invasion of the splenic vein; and formation of perisplenic collateral vessels. Metastatic lesions were also seen in the liver, bones, and lungs. DOTATATE PET/CT scan showed variable uptake, not a definitive pattern for PCC or neuroendocrine tumor (NET). Labs showed normal levels of plasma fractionated MN and CA, dopamine, renin, aldosterone, cortisol, ACTH, and DHEA-S. Chromogranin A (CgA) was elevated to &amp;gt;8000 ng/dL. Biopsy taken from one of the liver lesions was consistent with metastatic PCC. No family history of NET. Genetic testing was offered, but was deferred. Due to the large tumor burden, she was determined to be nonsurgical and started on systemic therapy with sunitinib. Doxazosin was also added, which better controlled her BP. After 9 months of sunitinib therapy, a repeat CT scan showed overall stable metastatic lesions, but the left AdM had enlarged to 16 cm. Given the slowly worsening disease, patient was switched to temozolomide. She is still actively being treated and monitored today. Discussion: The clinical features of PCC result from excessive CA secretion. HTN is the hallmark of CA release, but the amount, type, and pattern of CA secretion is extremely variable, leading to varied clinical presentations. CgA secretion is also elevated in PCC, but is generally a non-specific marker as its level is also increased in multiple NETs and non-endocrine medical conditions. About 9% of patients with PCC may have normal biochemical workup, with this being even rarer in malignant cases. In general, the amount of CA, MN, and CgA released by the tumor is also positively correlated with the tumor size. The case above is unique in that despite the large tumor burden the patient only presented with HTN and had normal MN and CA levels. Her CgA was significantly elevated, which could correlate with the tumor size, but was interestingly the only marker elevated. It appears that CgA could be a useful adjunct in the diagnosis of PCC, especially in cases where PCC appeared to be non-secretory. Presentation: 6/3/2024

6575 From Tonsils to the Thyroid: A Rare Case of Acute Suppurative Thyroiditis in an Immunocompetent Adult

Abstract Disclosure: F. Sajid: None. A. Mubashir: None. F. Mohsin: None. M. Sattar: None. Introduction: Acute suppurative thyroiditis (AST) is a rare infection of the thyroid gland due to its high vascularity, protective encapsulation, and high iodine content. Most AST cases occur in children with anatomical aberrations or in immunosuppressed adults. Here, we describe a case of AST in an immunocompetent woman. Case: A 54-year-old woman with no medical history presented to the emergency department due to dyspnea, dysphagia, and odynophagia for two days. She reported a four-day history of sore throat, fever, and chills. She was saturating well on room air but was sitting in a tripod position. She had erythema, swelling, tenderness to palpation in the anterior neck with a hoarse voice, and moderate trismus. Nasopharyngoscopy revealed no mass, but the scope could not pass beyond the velum due to edema. The patient’s condition quickly deteriorated, necessitating emergent intubation for acute hypoxic respiratory failure. After intubation, the patient had cardiac arrest with asystole requiring resuscitation and successful ROSC. The initial CT scan showed extensive soft tissue abnormalities in the nasopharynx and parapharyngeal tissues, extending to the thyroid gland and mediastinum with the possibility of developing abscesses. A thyroid ultrasound showed a heterogeneous thyroid gland without nodules or increased vascularity. Treatment commenced with ampicillin-sulbactam. Laboratory results showed Free T4 of 4.74 ng/dL (0.58-1.64), TSH 0.03 MCIU/mL (0.39-4.08), Total T3 1.56 ng/dL (0.72-1.35), WBC 19.3 K/UL (4.8-10.8), and elevated ESR and CRP levels. Thyroid-stimulating Immunoglobulin (TSI), Thyroid Peroxidase (TPO) Antibody, and Thyrotropin Binding Inhibitory Immunoglobulin (TBII) were negative, making AST the top differential. Methimazole was initiated due to concerns of thyroid storm, but it was quickly tapered due to a significant decrease in Free T4 levels and suspicion of AST. A repeat CT scan revealed more defined abscesses along the bilateral pharyngeal walls extending to the thyroid bed. The patient underwent bilateral tonsillectomy and drainage of the abscesses. She was extubated the following day. Cultures from the abscesses grew rare Klebsiella pneumoniae, susceptible to Ampicillin-sulbactam. A barium swallow on day 14 showed no evidence of a pyriform sinus fistula. She was discharged on day 15 with Augmentin for 7 days. On discharge, free T4 decreased to half (2.39 ng/dL), and Total T3 normalized (1.08ng/dL). Conclusion: This case presents a rare instance of AST in an immunocompetent patient without anatomical anomalies, stemming from the spread of peritonsillar and parapharyngeal abscesses into the thyroid bed. AST should be considered in cases of deep neck infections, as it is a potentially life-threatening disease. It is crucial to identify and treat AST early to prevent complications. The primary treatment involves antibiotics, incision, and drainage. Presentation: 6/1/2024

7648 Bilateral Adrenal Hemorrhage After Laminectomy: A Rare Complication

Abstract Disclosure: M. Rizk: None. S. Sharma: None. H. Qadeer: None. R. Paudel: None. C. Sherpa: None. Introduction: Bilateral Adrenal Hemorrhage (BAH) is an exceedingly uncommon complication of laminectomy, with few cases reported in the literature. In patients with history of any surgical procedure who present with unexplained symptoms of abdominal pain, back pain, hypotension, fever, confusion, or electrolyte abnormalities especially hyponatremia, acute adrenal insufficiency (AI) should be highly suspected. We herein describe a case of BAH following laminectomy. Clinical Case: 63-year-old male with past medical history of hypertriglyceridemia was admitted for post traumatic L1 burst fracture and was treated with T11-L3 fusion and T12-L3 laminectomy. The patient had normal bilateral adrenal glands after the fall on CT thoracic/lumbar spine imaging. The course was complicated by thrombocytopenia initially thought to be induced by therapeutic heparin since heparin antibody was positive. Serotonin-release assay returned negative weeks later ruling out heparin induced thrombocytopenia. Two weeks later, he developed unexplained tachycardia and CT angiogram was done which showed segmental pulmonary embolism and bilateral adrenal nodules measuring at least 3.9 cm on right side and 3.3 cm on left side. He was treated with Eliquis and was discharged home. Two weeks later, he was readmitted with weight loss of 30 lbs, weakness and altered mental status. His vital signs were significant for hypotension and tachycardia. Initial work up showed profound hyponatremia (sodium 121 mEq/L), hyperkalemia (potassium 6.1 mEq/L), hypoglycemia (Glucose 58 mg/dL), hypercalcemia (calcium 11.7 mg/dL) and acute kidney injury (creatinine 2.58 mg/dL). Repeat CT scan of chest/abdomen/pelvis without contrast showed bilateral hyperdense 4 cm adrenal mass/hematoma. Since initial CT of thorax/spine done after the fall showed normal adrenal glands, the new bilateral hyperdense adrenal masses noted post procedure is suggestive of adrenal hemorrhage/hematoma. Undetectable cortisol and high ACTH confirmed AI. Patient was treated with stress dose hydrocortisone followed by slow taper. MRI of pituitary gland showed partial empty Sella however since ACTH was high, empty sella was only an incidental finding and not the cause of AI. He is maintained on hydrocortisone 15 mg in the morning and 5 mg in the evening plus fludrocortisone 0.1 mg daily. His fatigue has improved, he is gaining weight and electrolytes are normal. Conclusions: This case report emphasizes the significance of timely diagnosis and management of BAH, which leads to primary AI. BAH is a rare complication following laminectomy. Clinicians should be aware of this possibility and consider it in the differential diagnosis of postoperative abdominal pain and electrolyte abnormalities, especially hyponatremia. Timely recognition and high index of suspicion should prompt empiric glucocorticoid replacement to decrease mortality. Presentation: 6/1/2024

Repeated CT scans on 12,984 Asians to diagnose lung cancer once it is suspected.

In Taiwan, lung cancer remains the leading cause of cancer-related fatalities, resulting in substantial healthcare expenses. This research aims to evaluate both the frequency and the costs of low-dose computed tomography (LDCT) in individuals suspected of having lung cancer until their diagnosis of cancer. LDCT screening was not conducted on a population-wide scale, and asymptomatic participants had to cover the expenses for the screening personally or reimburse from other sources. If the screening results were positive or suspicious, National Health Insurance (NHI) could be utilized for subsequent follow-up examinations. This cohort study utilized the NHI Database and focused on individuals with suspected cases of lung cancer identified between 2010 and 2014.A total of 17,572 suspected new lung cancer cases were initially identified and assigned to the relevant International Classification of Diseases codes. Individuals with suspected lung cancer received a diagnosis following an average follow-up period of 2.24 (95%CI, 2.11-2.37) years, and required the use of 2.36 (95%CI, 2.20-2.51) repeated CT scans. The NHI expenditures incurred by the use of CT scans for monitoring suspected lung cancer cases were relatively modest.

Autodelineation methods in a simulated fully automated proton therapy workflow for esophageal cancer

Background and purposeProton Online Adaptive RadioTherapy (ProtOnART) harnesses the dosimetric advantage of protons and immediately acts upon anatomical changes. Here, we simulate the clinical application of delineation and planning within a ProtOnART-workflow for esophageal cancer. We aim to identify the most appropriate technique for autodelineation and evaluate full automation by replanning on autodelineated contours. Materials and methodsWe evaluated 15 patients who started treatment between 11-2022 and 01-2024, undergoing baseline and three repeat computed tomography (CT) scans in treatment position. Quantitative and qualitative evaluations compared different autodelineation methods. For Organs-at-risk (OAR) deep learning segmentation (DLS), rigid and deformable propagation from baseline to repeat CT-scans were considered. For the clinical target volume (CTV), rigid and three deformable propagation methods (default, heart as controlling structure and with focus region) were evaluated. Adaptive treatment plans with 7 mm (ATP7mm) and 3 mm (ATP3mm) setup robustness were generated using best-performing autodelineated contours. Clinical acceptance of ATPs was evaluated using goals encompassing ground-truth CTV-coverage and OAR-dose. ResultsDeformation was preferred for autodelineation of heart, lungs and spinal cord. DLS was preferred for all other OARs. For CTV, deformation with focus region was the preferred method although the difference with other deformation methods was small. Nominal ATPs passed evaluation goals for 87 % of ATP7mm and 67 % of ATP3mm. This dropped to respectively 2 % and 29 % after robust evaluation. Insufficient CTV-coverage was the main reason for ATP-rejection. ConclusionAutodelineation aids a ProtOnART-workflow for esophageal cancer. Currently available tools regularly require manual annotations to generate clinically acceptable ATPs.

EP267 - Patient with Pneumomediastinum and Pneumoperitoneum – Importance of Human Factors

Abstract Clinical assessment 70-year-old lady presents with one-day history of dyspnoea, chest and abdominal pain. She was recently discharged following a three-week hospital admission with fall related traumatic rib fractures and hospital acquired pneumonia. Her abdomen was soft and non-tender. CT scan with oral and IV contrast demonstrates pneumomediastinum and pneumoperitoneum with connection at diaphragmatic crura. Management Patient was managed conservatively however two days after admission her CRP climbed to 150 and clinical suspicion remained high. Repeat CT scan over the weekend demonstrated increase in the pneumoperitoneum and decrease in the pneumomediastinum with a collection around sigmoid colon. Trainee raised concern to consultant and a laparotomy was done. Operative findings showed perforated sigmoid colon with faeculent peritonitis of unclear cause. Hartmann’s procedure was done and patient continued post recovery in ITU. Discussion This case demonstrates the complex varying presentations of our elderly co-morbid population. The presence of air in thoracic and abdominal cavities with unknown cause weeks after the fall was suspicious. Hence, the team communicated well from top-down and likewise from weekday to weekend. Low threshold for escalation and high index of suspicion enabled a re-scan which proved to be life-saving for this patient. Identifying complicated cases where errors can occur is a critical first step. Clear communication among staff, accurate documentation and addressing the patient concerns enabled the surgical team to navigate the complex disease process and ensure safe patient care.

Radiologic findings of occult nodal metastasis during clinically-N0 salvage total laryngectomy.

Occult nodal disease (OND) during clinically-N0 salvage total laryngectomy (TL) can be detected with the Neck-Imaging-Reporting-and-Data-Systems (NI-RADS). However, some patients will still have OND revealed on final pathology. A retrospective study on all patients who had OND during salvage TL with elective neck dissection (END) between 2009 and 2021 was performed. Repeat CT and PET scan interpretation was performed to evaluate their preoperative imaging for suspicious features. Among 81 salvage TL patients undergoing END, 12 (16%) had OND and a total of 26 occult nodes were identified. On pathology, the average node length [SD] was 0.6 cm [0.3]. On CT, 31% (8 of 26) had rounded morphology. On PET, most had SUVmax below blood pool. One patient scored NI-RADS 2; the rest scored 1. On re-review of preoperative imaging, occult nodes were subtle and challenging to identify. Despite no clear impact on survival, performing an END may provide prognostic information.

Phase II study of induction platinum doublet in combination with nivolumab followed by surgery or concurrent chemotherapy-nivolumab-radiation in unresectable stage IIIA-C non-small cell lung cancer (NSCLC).

TPS8122 Background: For patients (pts) with stage IIIA-IIIC NSCLC, though standard of care chemo-radiation (XRT) followed by 1 year of durvalumab has improved 5 year overall survival (OS), fewer than 50% survive 5 years. In this study, we adopted the established neoadjuvant chemotherapy (chemo) plus nivolumab (nivo) CheckMate-816 regimens for resectable stage I(&gt;4cm)-IIIA yielding an increased complete pathologic response (pCR) rate and event free survival compared to chemo alone, as induction therapy in unresectable stage IIIA-IIIC NSCLC. The intent is to use induction chemo-nivo to treat pts traditionally considered unresectable (multi-station N2 or N3 disease) in order to downstage them enough to permit surgical resection. The study is structured to change (1) the immune checkpoint inhibitor (ICI) regimen to induction rather than consolidation which enables the chance to observe the systemic therapy’s efficacy, treat micro-metastatic disease earlier, and may decrease the morbidity of the ablative therapies (2) the ICI containing regimen by increasing from single agent ICI to combination chemo plus nivo which may improve systemic efficacy (3) the duration of treatment with pre and post ablative ICI containing therapy.Induction also provides a platform for studying tumor biology with the chance to discover surrogate markers of response and resistance to the induction regimen matched against response ahead of the definitive therapy. Methods: This is an investigator initiated trial for pts with newly diagnosed clinical stage IIIA-IIIC EGFR/ALK/ROS1 WT, SQ and NSQ NSCLC with PS 0-1. Pts must be able to tolerate surgery and have a primary tumor which is technically resectable with an N stage IIIA &gt; 2 or more lymph node (LN) stations positive. Pts are treated with the same platinum doublet plus nivo regimens used in CheckMate-816 for 3 cycles followed by repeat CT and repeat biopsy of all LN stations biopsied at baseline and LN stations which at baseline had a high suspicion of harboring disease and which look technically unresectable. If the cancer is down-staged to a single LN station-N2, or is N1 or N0, the pt is offered surgery with an option of post-operative XRT. If not sufficiently down-staged, pts are treated with definitive chemo-nivo-XRT. All pts receive 1 year of consolidation nivo. The primary outcome is response to the induction regimen by repeat CT scan. Secondary outcomes include the rate of converting non-surgical stage III(A-C) to surgically resectable disease, pCR rate, extent of post-induction XRT field decrease, 2-year progression free survival, OS, quality of life, and exploratory outcomes include markers of resistance and response, and remote symptom monitoring. Enrolment will be 37 pts. The study is accruing with a plan to open at a second site. Clinical trial information: NCT06003075 .

Triage of advanced cervical cancer through immunotherapy induction (TRACTION).

TPS5622 Background: In advanced/recurrent cervical cancer, immune checkpoint inhibitors have emerged as an attractive alternative and have demonstrated impressive therapeutic responses. As a result, the combination of pembrolizumab with platinum/taxane chemotherapy with or without bevacizumab received FDA approval for first-line systemic therapy in persistent, recurrent, or metastatic PD-L1+ cervical cancer. However, this regimen demonstrates the greatest impact on survival when all four drugs are utilized and are not without the potential for significant toxicity. CheckMate-358 utilized two dosing regimens of ipilimumab and nivolumab in advanced/recurrent cervical cancer. In the preliminary results, the utilization of either dosing regimen resulted in remarkable, durable responses in chemo-naïve patients with the median overall survival not reached. Given the potential benefit of CTLA-4/PD-1 blockade in the upfront setting, we propose a phase II trial examining the strategy of induction immunotherapy with lorigerlimab (bispecific antibody targeting CTLA-4 and PD-1) in chemo-naïve cervical cancer patients not amenable to curative treatment. Methods: The study is a phase II, multi-site clinical trial conducted at MD Anderson Cancer Center and Lyndon B. Johnson General Hospital. In the induction phase, patients will receive intravenous (IV) lorigerlimab at the recommended phase II dose (6 mg/kg) for three 21-day cycles with a repeat CT scan performed at week 9 of treatment. Tumor response (by RECIST v1.1) to induction immunotherapy will be used to triage patients to either continuation of lorigerlimab (if at least stable disease) or standard of care treatment (if disease progression) in the triaged treatment phase. Lorigerlimab will be continued until progression or intolerable toxicity, for a maximum of 35 cycles. At any time point, all patients at first disease progression will subsequently receive physician’s choice standard of care systemic therapy with carboplatin/paclitaxel +/- pembrolizumab +/- bevacizumab and will be followed for survival. The primary objective is to estimate disease control rate. Secondary objectives are to determine objective response rate, duration of response, overall survival, progression-free survival, and safety (by CTCAE v5.0). Key eligibility criteria include 1) recurrent, metastatic, or persistent cervical cancer 2) squamous cell carcinoma, adenosquamous, or adenocarcinoma histologic subtype 3) not amenable to curative surgery or radiation. The trial is open with 14 of planned 40 patients enrolled at the time of submission. Clinical trial information: NCT05475171 .

#2538 Asymptomatic perirenal lymphoma: an unusual presentation of primary lymphoma

Abstract Background and Aims Isolated perinephric lymphoma is uncommon clinicopathological entity, reported in less than 10% of cases. Although this is rare finding, every perirenal mass require prompt diagnosis and multidisciplinary approach if needed. Method We described a case of a asymptomatic young woman who presented with accidental ultrasound finding of a „kidney sweat sign“. Results A 40 year old woman was reported to nephrologist after ultrasonography incidentally revealed a „kidney sweat sign“. The patient had normal kidney function and was symptom-free. Also, all laboratory findings were within the reference range. She was admitted to the nephrology department and CT urography, followed by the ultrasound guided coarse needle biopsy was performed. CT scan revealed right perirenal area completely filled with soft tissue mass that was making an external compression of the right kidney with no infiltration of renal tissue, while pathohistology examination of the biopsy core showed non Hodgkin B cell lymphoma of marginal zone. Immunohistochemistry study demonstrated CD20+, CD3-,CD5-, bcl 2+, bcl 6-, CD10-, CD21-, CD23-, CD38+, cyclin D1-, Ki67+ in 5–10 tumor cells. The patient was reported to hematologist where she underwent bone marrow biopsy which did not show evidence of lymphoma involvement. She was initiated on chemotherapeutic treatment R- COP (Rituximab, cyclophosphamide, vincristine and prednisone). Until now she received three doses of immunochemotherapy and showed good response to the therapy with decrease in the mass dimensions at the repeated CT scan without signs of disease dissemination. Conclusion This case report highlights the importance of an urgent and expeditious work up, including both CT scan and biopsy. Multidisciplinary approach in order to get timely diagnosis and treatment are imperative to achieve improved outcomes.

Impact of deep learning image reconstruction on volumetric accuracy and image quality of pulmonary nodules with different morphologies in low-dose CT

BackgroundThis study systematically compares the impact of innovative deep learning image reconstruction (DLIR, TrueFidelity) to conventionally used iterative reconstruction (IR) on nodule volumetry and subjective image quality (IQ) at highly reduced radiation doses. This is essential in the context of low-dose CT lung cancer screening where accurate volumetry and characterization of pulmonary nodules in repeated CT scanning are indispensable.Materials and methodsA standardized CT dataset was established using an anthropomorphic chest phantom (Lungman, Kyoto Kaguku Inc., Kyoto, Japan) containing a set of 3D-printed lung nodules including six diameters (4 to 9 mm) and three morphology classes (lobular, spiculated, smooth), with an established ground truth. Images were acquired at varying radiation doses (6.04, 3.03, 1.54, 0.77, 0.41 and 0.20 mGy) and reconstructed with combinations of reconstruction kernels (soft and hard kernel) and reconstruction algorithms (ASIR-V and DLIR at low, medium and high strength). Semi-automatic volumetry measurements and subjective image quality scores recorded by five radiologists were analyzed with multiple linear regression and mixed-effect ordinal logistic regression models.ResultsVolumetric errors of nodules imaged with DLIR are up to 50% lower compared to ASIR-V, especially at radiation doses below 1 mGy and when reconstructed with a hard kernel. Also, across all nodule diameters and morphologies, volumetric errors are commonly lower with DLIR. Furthermore, DLIR renders higher subjective IQ, especially at the sub-mGy doses. Radiologists were up to nine times more likely to score the highest IQ-score to these images compared to those reconstructed with ASIR-V. Lung nodules with irregular margins and small diameters also had an increased likelihood (up to five times more likely) to be ascribed the best IQ scores when reconstructed with DLIR.ConclusionWe observed that DLIR performs as good as or even outperforms conventionally used reconstruction algorithms in terms of volumetric accuracy and subjective IQ of nodules in an anthropomorphic chest phantom. As such, DLIR potentially allows to lower the radiation dose to participants of lung cancer screening without compromising accurate measurement and characterization of lung nodules.

Development of an adjustable patient-specific rigid guide to improve the accuracy of external ventricular catheter placement.

The most common method for external ventricular drain (EVD) placement is the freehand approach, which has reported inaccuracy rates of 12.3%-44.9%, especially in the case of altered ventricular anatomy. Current assistive devices require added time or equipment or do not account for shifted ventricles. To improve the accuracy of emergent EVD placement in the setting of altered ventricular anatomy, the authors designed a patient-specific EVD (PS-EVD) guide. The PS-EVD guide has a tripod base and a series of differently angled inserts that lock in place at multiple rotational positions, allowing for numerous insertion angles. For testing, the authors designed a 3D-printed phantom skull with a gelatin brain analog containing ventricles simulating normal and altered ventricular anatomy. Low-resolution CT scans of the phantom were used to calculate the insertion angle in relation to the standard perpendicular entry. The corresponding insert at the correct rotational position within the base unit was positioned over the entry point on the phantom, and the catheter was inserted. Accuracy was evaluated with repeat CT scans. With normal ventricular anatomy, as well as abnormally shifted ventricles, proper use of the PS-EVD guide led to accurate catheter insertion into the ventricle in trials, as confirmed on coronal and sagittal CT images, including cases in which a perpendicular trajectory, such as with the Ghajar guide, was insufficient. The PS-EVD guide allows consistent and accurate EVD placement in phantom skulls with both normal and altered ventricular anatomy. Further trials comparing this device to the freehand approach are required.

Clinical application of serum seven tumour-associated autoantibodies in patients with pulmonary nodules

BackgroundThe incidence of pulmonary nodules is increasing because of the promotion and popularisation of low-dose computed tomography (LDCT) screening for populations with suspected lung cancer. However, a high rate of false positives and concerns regarding the radiation-related cancer risk of repeated CT scanning remain major obstacles to its wide application. This study aimed to investigate the clinical value of seven tumour-associated autoantibodies (7-TAAbs) in the differentiation of malignant pulmonary tumours from benign ones and the early detection of lung cancer in routine clinical practice. MethodsWe included 377 patients who underwent both the 7-TAAbs panel test and LDCT screening, and were diagnosed with pulmonary nodules using LDCT. An enzyme-linked immunosorbent assay (ELISA) was used to measure the serum levels antibodies for P53, PGP9.5, SOX2, GAGE7, GBU4-5, CAGE, and MAGE-A1. The relationships between the positive rates of the 7-TAAbs and the patient sex, and age, and the number, size, and composition of pulmonary nodules were analysed. We then statistically evaluated the clinical application value. ResultsThe positive rates of the 7-TAAbs did not correlate with sex, age, number, size, or composition of pulmonary nodules. The serum antibody level of GBU4-5 in patients with pulmonary nodules tended to increase with age; the serum antibody level of SOX2 tended to increase with nodule size and was the highest among patients with mixed ground-glass opacity (mGGO) nodules. The antibody positive rate for CAGE in female patients with pulmonary nodules was significantly higher than that in male patients (P < 0.05). The positive rate of GBU4-5 antibody in patients aged 60 years and above was higher than that in younger patients (P < 0.05). The positive rate of GAGE7 antibody in patients with pulmonary nodules sized 8–20 mm was also significantly higher than that in patients with pulmonary nodules sized less than 8 mm (P < 0.01). Significant differences were observed in the GAGE7 antibody levels of patients with pulmonary nodules of different compositions (P < 0.01). The positive rate of the 7-TAAbs panel test in patients with lung cancer was significantly higher than in patients with pulmonary nodules (P < 0.01). Serum levels of P53, SOX2, GBU4-5, and MAGE-A1 antibodies were significantly higher in patients with lung cancer than in those with pulmonary nodules (P < 0.05). ConclusionThe low positive rates of serum 7-TAAbs in patients with lung cancer and pulmonary nodules may be related to different case selection, population differences, geographical differences, different degrees of progression, and detection methods. The combined detection of 7-TAAbs has some clinical value for screening and early detection of lung cancer.

Spatiotemporal changes in imaging features associated with diffuse idiopathic skeletal hyperostosis (DISH)

ObjectivesThe purpose of our study was to characterise spatiotemporal features of disease progression in people with diffuse idiopathic skeletal hyperostosis (DISH), early-phase DISH, and those not meeting either criterion who...

Various Approaches in Managing Fish Bone Migration: Our Experience in Tertiary Hospital in Sarawak.

Ingested fish bone is a common otorhinolaryngology emergency in Malaysia. Fish bone is commonly impacted in the oropharynx for young patients and oesophagus for elderly patients. Rarely, a fish bone migrated extraluminal and require surgical exploration. We report a five cases of fish bone which involved extraluminal migration, and needed repeat CT scans and various types of surgical exploration.