Gastric cystica profunda: Another indication for minimally invasive endoscopic resection techniques?

Gastric cancer presents a significant global health burden, as it is the fifth most common malignancy and fourth leading cause of cancer mortality worldwide. Variations in incidence rates across regions underscores the multifactorial etiology of this disease. The overall 5-year survival rate remains low despite advances in its diagnosis and treatment. Although surgical gastrectomy was previously standard-of-care, endoscopic resection techniques, including endoscopic mucosal resection and endoscopic submucosal dissection (ESD) have emerged as effective alternatives for early lesions. Compared to surgical resection, endoscopic resection techniques have comparable 5-year survival rates, reduced treatment-related adverse events, shorter hospital stays and lower costs. ESD also enables en bloc resection, thus affording organ-sparing curative endoscopic resection for early cancers. In this editorial, we comment on the recent publication by Geng et al regarding gastric cystica profunda (GCP). GCP is a rare gastric pseudotumour with the potential for malignant progression. GCP presents a diagnostic challenge due to its nonspecific clinical manifestations and varied endoscopic appearance. There are several gaps in the literature regarding the diagnosis and management of GCP which warrants further research to standardize patient management. Advances in endoscopic resection techniques offer promising avenues for GCP and early gastric cancers.

The role of MRI biomarkers in evaluation of symptomatic pineal cysts - a retrospective analysis.

BACKGROUND: Our aim was to determine whether the Apparent Diffusion Coefficient is able to predict the presence of a symptomatic pineal cyst by detecting cerebral edema. METHODS: We retrospectively analyzed MRIs of 45 patients with pineal cysts before and after resection and 51 patients without pineal cysts, comparing ADC values of thalamus, central, periventricular and subcortical white matter. Furthermore we evaluated cyst size and morphology and analyzed its correlation to ADC values in corresponding patients. RESULTS: Differences between patients with symptomatic pineal cyst and control group were not significant (p = 0.200 - 0.968). ADC ratios did not change significantly after resection of the cyst (p = 0.575 - 0.862). Cyst size showed no significant correlation to ADC ratios (p = 0.071 - 0.918). Raw data analyses revealed more significance, especially periventricularly and in central white matter, which resulted in significant interhemispheric differences in ADC ratios in both subgroups (p < 0.001 and p = 0.031). MRI of 1.5T showed consistently higher values than 3T but mostly insignificant. CONCLUSION: Our analysis revealed no evidence that pineal cysts lead to intracerebral edema caused by venous compression. Since variability was higher than the differences seen, ADC sequences do not appear to be an appropriate diagnostic tool for symptomatic pineal cysts.

Case series multilocular cystic hemangioma of the liver: Three cases and literature review.

RATIONALE: Multilocular cystic hemangioma is a rare benign tumor classified as an atypical hemangioma. Currently, there are limited imaging reports available, and the imaging characteristics can be challenging to distinguish from other malignant multilocular cystic liver diseases such as cystadenocarcinoma, necessitating confirmation through pathological diagnosis. Here, we discuss the imaging features of 3 cases of multilocular cystic hemangiomas. PATIENT CONCERNS AND DIAGNOSES: Case 1 was a 24-year-old young female, and Case 2 involved a 60-year-old elderly male. Both patients were asymptomatic and physical examination revealed hepatic space-occupying lesions. Imaging findings revealed multilocular cystic lesions in the left liver with septa, calcification, a high diffusion-weighted magnetic resonance imaging (DWI) signal at the edge of the lesion, and progressive enhancement of the cyst wall and septa. Case 3 involved a 50-year-old male patient with epigastric distending pain for 1 month and sudden severe abdominal pain for 14 hours. Imaging results revealed a multilocular cystic lesion in the left liver with septa and tumor bleeding, a high DWI signal, and an enhanced cyst wall and septa. The pathological diagnosis confirmed a hepatic hemangioma. INTERVENTIONS: All 3 patients underwent liver tumor resection. OUTCOMES: All 3 patients recovered successfully without any intraoperative or postoperative complications during the follow-up periods of 5 years, 6 months, and 5 months. There were no signs of recurrence. LESSONS: Liver imaging revealed multilocular cystic lesions with features, such as compartmentalization, calcification, or bleeding. Multilocular cystic hemangiomas should be considered in imaging diagnosis. Enhancing our understanding of multilocular cystic hemangiomas can aid in improving the differential diagnosis of other malignant multilocular cystic liver diseases, ultimately reducing unnecessary liver resection.

Preoperative diagnosis of cervical cystic lesions using magnetic resonance imaging: a retrospective study.

BACKGROUND: We conducted this study to clarify the magnetic resonance imaging (MRI) characteristics of lobular endocervical glandular hyperplasia (LEGH) and Nabothian cysts. METHODS: This study included 48 patients who underwent hysterectomy at our institution between 2016 and 2020 for suspected LEGH. Histopathological studies confirmed the presence of 25 Nabothian cysts and 23 cases of LEGH. We retrospectively analyzed five characteristic MRI findings: (1) located at the upper cervical canal, (2) positioned within the cervical stroma, (3) not circumscribing the cervical canal, (4) low- to iso-intensity on T1-weighted images (T1WI), and (5) "cosmos" or "microcystic" pattern. We compared the diagnostic accuracy of these findings for LEGH and Nabothian cysts using sensitivity, specificity, and predictive values. Combinations of findings were also calculated. RESULTS: The characteristics "cosmos" or "microcystic" pattern, lesion not circumscribing the cervical canal, and low/iso-intensity on T1WI had a sensitivity and specificity greater than 50%. The sensitivity was 73.9% and specificity 84.0% when a combination of "cosmos" or "microcystic" pattern and lesion not circumscribing the cervical canal was present. CONCLUSION: The coexistence of a "cosmos" or "microcystic" pattern and not circumscribing the cervical canal was the most characteristic finding that distinguished LEGH from Nabothian cysts. When neither of these findings is present, Nabothian cyst can be suspected.

Cysts of the ligamentum flavum are often linked to ischemic conditions: A morphological study.

"Cysts of the ligamentum flavum (cysts-LF)" is the term for non-neoplastic cystic lesion involving LF. The aim of the present study was to elucidate the histopathological characteristics and pathogenesis of "cysts-LF". Herein, we defined cysts-LF as spinal cysts containing degenerative LF components. From archival cases, we investigated 18 symptomatic cysts-LF surgically removed from 18 patients (13 males and five females; median age 68.5 years [range, 42-86 years]). The elastic fibers of LF components in the wall were separated and/or torn, and cyst walls were accompanied by chondroid metaplasia (17 cases), myxoid changes (13 cases), ossification (11 cases), amyloid deposits (14 cases), hemosiderosis (six cases), granular/smudgy calcification (four cases), synovial cell linings (three cases), and severe inflammatory infiltrates (one case). These histologic features of our cysts-LF were shared by previously reported "cysts-LF." Fourteen cysts-LF demonstrated vascular stenosis/occlusion, and eight showed thick hyalinized vessels, suggesting local circulatory insufficiency. Eight cases (44%) exhibited lipomembranous fat necrosis, accompanied by hyalinized vascular changes (p = 0.003). Ischemic conditions were observed in nearly half of the present cysts-LF, and may be one of the main contributing factors for the formation of cysts-LF, via degeneration and cystic changes in the LF.

Adrenal cysts less than 10 cm can be safely observed.

BACKGROUND: Adrenal cysts are rare and appropriate management is unclear due to a lack of data on their natural history. Understanding adrenal cyst growth patterns would assist in clinical management. METHODS: This single-institution study included all adult patients diagnosed with simple adrenal cysts between 2004 and 2021. Baseline characteristics and outcomes of those who underwent resection (ADX) or observation (OBS) were compared using the chi-squared test, student's t-test, and Wilcoxon rank-sum test. Growth curves and sensitivity analysis were plotted for all patients who had follow-up imaging. RESULTS: We identified 77 patients with imaging-confirmed adrenal cysts. The majority were female (75.3%) and more than half were white (55.8%). One-third of patients underwent ADX, and the remaining were observed. ADX patients were younger (median age [IQR]: 55.5 y [45.0-68.2 y] vs. 44.2 y [38.7-55.0 y], p = 0.01) and more likely to be Hispanic (12% vs. 0%, p = 0.05). ADX patients presented with larger cysts (5.6 vs. 2.6 cm, p = 0.002). The median time from diagnosis to last follow-up was 1.1 y for ADX and 4.1 y for OBS. Average growth for OBS was 0.3 cm/y, while average growth for ADX was 3.9 cm/y. In ADX patients, cysts >10 cm grew significantly faster than cysts <10 cm (median growth rate 13.2 cm/y vs. 0.3 cm/y, p < 0.05). There was no adrenal malignancy diagnosis, hyperfunctionality, or observation-related complications (e.g., rupture). CONCLUSION: While size >4-6 cm has guided surgical referral for solid adrenal masses, this study demonstrates a size threshold of 10 cm, below which asymptomatic, simple adrenal cysts can safely be observed.

Presacral Tailgut Cyst.

A tailgut cyst is a rare benign polycystic congenital lesion in presacral or retrorectal space, when there is failure of involution of tailgut. Clinical presentation may be with or without symptoms of different types related to obstruction, infection, or rarely malignancy. Symptoms may be misleading and atypical, so understanding of characteristics of tailgut cysts is important for precise and early diagnosis to be made for proper treatment and to avoid complications and malignant transformation. Magnetic resonance imaging pelvis was used as diagnostic imaging investigation, but the final confirmation was only done by histopathology. Definitive treatment is surgery, though various surgical approaches are described, surgery is tailored which will suit the individual patient's anatomy and suspected diagnosis of mass. This case review used PubMed and Web of Science databases to search for the studies. We found around 176 articles and selected 77 articles in our survey, with 8 reviews, 31 case reports, and 31 case reports and reviews.

RésuméUn kyste intestinal est une lésion congénitale polykystique bénigne rare dans l'espace présacré ou rétrorectal, en cas d'échec de l'involution de l'intestin grêle. La présentation clinique peut être accompagnée ou non de symptômes de différents types liés à une obstruction, une infection ou, plus rarement, une tumeur maligne. Les symptômes peuvent être trompeurs et atypiques, c'est pourquoi il est important de comprendre les caractéristiques des kystes de l'intestin grêle pour établir un diagnostic précis et précoce afin d'établir un traitement approprié et d'éviter les complications et la transformation maligne. L'imagerie par résonance magnétique du bassin a été utilisée comme examen d'imagerie diagnostique, mais la confirmation finale n'a été faite que par histopathologie. Le traitement définitif est la chirurgie, bien que diverses approches chirurgicales soient décrites, la chirurgie est adaptée à l'anatomie de chaque patient et au diagnostic suspecté de masse. Cette revue de cas a utilisé les bases de données PubMed et Web of Science pour rechercher les études. Nous avons trouvé environ 176 articles et sélectionné 77 articles dans notre enquête, avec 8 revues, 31 rapports de cas et 31 rapports de cas et critiques.

A 10-year retrospective study of the risks and peculiarities in pediatric patients with (para)gonadal tumors and cysts.

INTRODUCTION: Gonadal pediatric tumors are rare, ranking fourth (6%) among pediatric tumors, by Surveillance, Epidemiology, and End Results Program (https:∕∕seer.cancer.gov∕). They have vague symptoms, leading to late discovery, but early detection and identifying its risk factors result in favorable prognosis and reduction of its incidence respectively. PATIENTS, MATERIAL AND METHODS: A 10-year retrospective study identified peculiarities and risk factors in 210 children till age 17 with (para)gonadal tumors. RESULTS: Stress, pollution (agricultural chemicals, insecticides and metal mine), obesity, breastfeeding ≤5 months, malformations [mainly non-genetic related 67∕87 (77%), especially eye malformation - 64%], hormone, smoking, positive heredo-genetic history, rural residence area, abnormal birth weight, and menstruation disorders showed an increased gonadal malignancy risk; relative risk ratio (RR): 1.33, 1.30, 1.34, 1.11, 1.65, 1.16, 1.36, 1.10, 1.00, 1.08 and 1.15 folds, respectively. RR for histopathological subtypes: immature teratoma (IT) (pollution - 1.75, Rhesus positive - 3.41), dysgerminoma (menstruation disorders - 2.80), granulosa cell tumor (stress - 2.10, menstruation disorders - 2.80), mucinous cystadenomas (obesity - 2.84, no postnatal vaccine - 3.71), mature teratomas (stress - 2.35, malformations - 2.18) and serous cystadenomas (breastfeeding ≤5 months - 2.53), dependent variables being mixed germ cell tumors (GCTs) and cysts. Children presenting with bleeding (73%), abdominal distention (62%), elevated tumor markers (91%), (multilocular) solid tumor (88% and 100%), tumor size >10 cm (65%), GCTs (74%), death (100%), metastases (100%), viruses (77%), loss of appetite (68%), and weight (85%), had gonadal malignant tumors, especially mixed GCTs and IT. CONCLUSIONS: Avoiding these risk factors will prevent and reduce gonadal pediatric tumors. Investigating children presenting with the listed peculiarities, especially if exposed to the mentioned risk factors, will enable early gonadal tumor identification, successful patient management, and favorable prognosis.

Placental Transmogrification of the Lung Presenting as Cystic-Solid Mass: A Case Report.

The gradually progressive solitary cystic-solid mass of chest CT scans is highly suggestive of lung cancer. We report a case of a 29-year-old woman with a persistent cystic-solid lesion in the right upper lobe. A chest CT scan showed a 35 mm × 44 mm × 51 mm focal cystic-solid mass in the anterior segment of the right upper lobe. The size of lesion had increased over 3 years, especially for the solid component. The right upper lobe pneumonectomy was performed. Postoperative pathological examination showed placental transmogrification of the lung, which is a rare cause of pulmonary cystic lesion.

Role of autophagy and ferroptosis in the development of endometriotic cysts (Review).

It is considered that the etiology of endometriosis is retrograde menstruation of endometrial tissue. Although shed endometrial cells are constantly exposed to a challenging environment with iron overload, oxidative stress and hypoxia, a few cells are able to survive and continue to proliferate and invade. Ferroptosis, an iron­dependent form of non­apoptotic cell death, is known to play a major role in the development and course of endometriosis. However, few papers have concentrated on the dynamic interaction between autophagy and ferroptosis throughout the progression of diseases. The present review summarized the current understanding of the mechanisms underlying autophagy and ferroptosis in endometriosis and discuss their role in disease development and progression. For the present narrative review electronic databases including PubMed and Google Scholar were searched for literature published up to the October 31, 2023. Autophagy and ferroptosis may be activated at early stages in endometriosis development. On the other hand, excessive activation of intrinsic pathways (e.g., estrogen and mechanistic target of rapamycin) may promote disease progression through autophagy inhibition. Furthermore, suppression of ferroptosis may cause further progression of endometriotic lesions. In conclusion, the autophagy and ferroptosis pathways may play a dual role in disease initiation and progression. The present review discussed the temporal transition of non­apoptotic cell death regulation during disease progression from retrograde endometrium to early lesions to established lesions.

HL156A, an AMP-Activated Protein Kinase Activator, Inhibits Cyst Growth in Autosomal Dominant Polycystic Kidney Disease.

BACKGROUND: Autosomal dominant polycystic kidney disease (ADPKD) is the most prevalent genetic kidney disorder. While metformin has demonstrated the ability to inhibit cyst growth in animal models of ADPKD via activation of adenosine monophosphate-activated protein kinase (AMPK), its effectiveness in humans is limited due to its low potency. This study explored the impact of HL156A, a new and more potent AMPK activator, in a mouse model of ADPKD. METHODS: To investigate whether HL156A inhibits the proliferation of renal cyst cells in ADPKD in vitro, exogenous human telomerase reverse transcriptase (hTERT)-immortalized renal cyst cells from ADPKD patients were treated with HL156A, and an MTT (dimethylthiazol-diphenyltetrazolium bromide) assay was performed. To assess the cyst-inhibitory effect of HL156A in vivo, we generated Pkd1 conditional knockout (KO) mice with aquaporin 2 (AQP2)-Cre, which selectively expresses Cre recombinase in the collecting duct. The effectiveness of HL156A in inhibiting cyst growth and improving renal function was confirmed by measuring the number of cysts and blood urea nitrogen (BUN) levels in the collecting duct-specific Pkd1 KO mice. RESULTS: When cyst cells were treated with up to 20 µM of metformin or HL156A, HL156A reduced cell viability by 25% starting at a concentration of 5 µM, whereas metformin showed no effect. When AQP2-Cre male mice were crossed with Pkd1flox/flox female mice, and when AQP2-Cre female mice were crossed with Pkd1flox/flox male mice, the number of litters produced by both groups was comparable. In collecting duct-specific Pkd1 KO mice, HL156A was found to inhibit cyst growth, reducing both the number and size of cysts. Furthermore, it was confirmed that kidney function improved as HL156A treatment led to a reduction in elevated BUN levels. Lastly, it was observed that the increase in AMPK phosphorylation induced by HL156A decreased ERK phosphorylation and α-SMA expression. CONCLUSION: HL156A has potential as a drug that can restore kidney function in ADPKD patients by inhibiting cyst growth.

ACG Clinical Guideline: Focal Liver Lesions.

Focal liver lesions (FLLs) have become an increasingly common finding on abdominal imaging, especially asymptomatic and incidental liver lesions. Gastroenterologists and hepatologists often see these patients in consultation and make recommendations for management of multiple types of liver lesions, including hepatocellular adenoma, focal nodular hyperplasia, hemangioma, and hepatic cystic lesions including polycystic liver disease. Malignancy is important to consider in the differential diagnosis of FLLs, and healthcare providers must be familiar with the diagnosis and management of FLLs. This American College of Gastroenterology practice guideline uses the best evidence available to make diagnosis and management recommendations for the most common FLLs.

NAMPT Overexpression Drives Cell Growth in Polycystic Liver Disease through Mitochondrial Metabolism Regulation.

A group of genetic diseases known as polycystic liver disease (PLD) are distinguished by the gradual development of fluid-filled hepatic cysts formed from cholangiocytes and commonly related to primary cilia defects. The NAD salvage pathway, which sustains cellular bioenergetics and supplies a required substrate for tasks important to rapidly multiplying cells, has a rate-limiting phase that is mediated by nicotinamide phosphoribosyltransferase (NAMPT). In this study, the efficacy and mechanisms of action of FK866, a novel, high-potency NAMPT inhibitor with a good toxicity profile, were assessed. NAMPT-siRNA and FK866 reduced NAD levels and inhibited the proliferation of PLD cells in a dose-dependent manner. Notably, this pharmacologic and siRNA-mediated suppression of NAMPT was less effective in normal cells at the same concentrations. The addition of nicotinamide mononucleotide (NMN), a byproduct of NAMPT that restores NAD concentration, rescued the cellular viability of PLD cells and verified the on-target action of FK866. In FK866-treated PLD cells, mitochondrial respiration and ATP production were impaired and reactive oxygen species production was induced. Importantly, FK866 treatment was associated with improved effects of octreotide, a drug used for PLD treatment. As a result, the use of NAMPT inhibitors, including FK866 therapy, offers the possibility of a further targeted strategy for the therapeutic treatment of PLD.

[Differential diagnosis of cystic and nodular lung diseases]. / Differenzialdiagnose zystischer und nodulärer Lungenkrankheiten.

BACKGROUND: Cystic and nodular lung diseases encompass a broad spectrum of diseases with different etiologies and clinicoradiological presentations. Their differentiation is crucial for patient management but can be complex due to diseases with features of both categories and overlapping radiological patterns. OBJECTIVE: This study aims to describe the imaging features of cystic and nodular lung diseases in high-resolution computed tomography (CT) in detail-primarily based on their etiology-in order to allow a more accurate differential diagnosis of these diseases. MATERIALS AND METHODS: A narrative review based on current literature on the topic was conducted from a clinicoradiological perspective. RESULTS: This paper systematically categorizes the differential diagnosis of cystic and nodular lung disease and provides insights into their radiological patterns and etiologies. It highlights the role of CT in the diagnosis of these diseases and emphasizes the importance of multidisciplinary panels combining expertise from radiology, pulmonology, rheumatology, and pathology. CONCLUSION: Reliable differential diagnosis of cystic and nodular lung diseases, particularly based on their radiological features alone, remains difficult due to their overlapping and dynamic nature. Multidisciplinary boards should be the clinical standard for accurate work-up of these diseases, as they combine the medical history, symptoms, radiological findings, and, if necessary, histopathological examinations, thus providing a more robust framework for diagnosis and management.

Lack of inflammation or immune response in cyst tissue of patients with symptomatic non-hydrocephalic pineal cysts.

Pineal cysts are frequently encountered as incidental findings in magnetic resonance imaging, usually devoid of symptoms, yet some patients exhibit symptomatic manifestations possibly associated with the cyst, even in the absence of hydrocephalus. The etiology of these symptoms remains contentious. This study aims to investigate the presence of lymphatic endothelial cell (LEC) markers and indications of inflammation or immune response within the pineal cysts of patients experiencing symptomatic non-hydrocephalic presentations. Eight patients who underwent surgical excision of their cysts were included in the study. Immunohistochemistry was utilized to assess the expression of LYVE-1, PDPN, and VEGFR3 as LEC markers, alongside IL-6 and CD3 for indications of inflammation or immune activity. Our analysis revealed an absence of inflammatory markers or immune response. However, a distinct expression of VEGFR3 was observed, likely localized to neurons within the pineal cyst tissue. We propose that these VEGFR3+ neurons within the pineal cyst may contribute to the headache symptoms reported by these patients. Further investigations are warranted to substantiate this hypothesis.

Defective mesenchymal Bmpr1a-mediated BMP signaling causes congenital pulmonary cysts.

Abnormal lung development can cause congenital pulmonary cysts, the mechanisms of which remain largely unknown. Although the cystic lesions are believed to result directly from disrupted airway epithelial cell growth, the extent to which developmental defects in lung mesenchymal cells contribute to abnormal airway epithelial cell growth and subsequent cystic lesions has not been thoroughly examined. In the present study using genetic mouse models, we dissected the roles of bone morphogenetic protein (BMP) receptor 1a (Bmpr1a)-mediated BMP signaling in lung mesenchyme during prenatal lung development and discovered that abrogation of mesenchymal Bmpr1a disrupted normal lung branching morphogenesis, leading to the formation of prenatal pulmonary cystic lesions. Severe deficiency of airway smooth muscle cells and subepithelial elastin fibers were found in the cystic airways of the mesenchymal Bmpr1a knockout lungs. In addition, ectopic mesenchymal expression of BMP ligands and airway epithelial perturbation of the Sox2-Sox9 proximal-distal axis were detected in the mesenchymal Bmpr1a knockout lungs. However, deletion of Smad1/5, two major BMP signaling downstream effectors, from the lung mesenchyme did not phenocopy the cystic abnormalities observed in the mesenchymal Bmpr1a knockout lungs, suggesting that a Smad-independent mechanism contributes to prenatal pulmonary cystic lesions. These findings reveal for the first time the role of mesenchymal BMP signaling in lung development and a potential pathogenic mechanism underlying congenital pulmonary cysts.

Congenital disorders are medical conditions that are present from birth. Although many congenital disorders are rare, they can have a severe impact on the quality of life of those affected. For example, congenital pulmonary airway malformation (CPAM) is a rare congenital disorder that occurs in around 1 out of every 25,000 pregnancies. In CPAM, abnormal, fluid-filled sac-like pockets of tissue, known as cysts, form within the lungs of unborn babies. After birth, these cysts become air-filled and do not behave like normal lung tissue and stop a baby's lungs from working properly. In severe cases, babies with CPAM need surgery immediately after birth. We still do not understand exactly what the underlying causes of CPAM might be. CPAM is not considered to be hereditary ­ that is, it does not appear to be passed down in families ­ nor is it obviously linked to any environmental factors. CPAM is also very difficult to study, because researchers cannot access tissue samples during the critical early stages of the disease. To overcome these difficulties, Luo et al. wanted to find a way to study CPAM in the laboratory. First, they developed a non-human animal 'model' that naturally forms CPAM-like lung cysts, using genetically modified mice where the gene for the signaling molecule Bmpr1a had been deleted in lung cells. Normally, Bmpr1a is part of a set of the molecular instructions, collectively termed BMP signaling, which guide healthy lung development early in life. However, mouse embryos lacking Bmpr1a developed abnormal lung cysts that were similar to those found in CPAM patients, suggesting that problems with BMP signalling might also trigger CPAM in humans. Luo et al. also identified several other genes in the Bmpr1a-deficient mouse lungs that had abnormal patterns of activity. All these genes were known to be controlled by BMP signaling, and to play a role in the development and organisation of lung tissue. This suggests that when these genes are not controlled properly, they could drive formation of CPAM cysts when BMP signaling is compromised. This work is a significant advance in the tools available to study CPAM. Luo et al.'s results also shed new light on the molecular mechanisms underpinning this rare disorder. In the future, Luo et al. hope this knowledge will help us develop better treatments for CPAM, or even help to prevent it altogether.

CT-Guided Core Needle Biopsy of Pulmonary Lesions Associated With Cystic Airspaces: A Case-Control Study.

BACKGROUND. Concern may exist that pulmonary lesions associated with cystic airspaces are at risk of increased biopsy complications or lower biopsy accuracy given challenges in targeting tissue abutting or intermingled with the cystic airspaces. OBJECTIVE. The purpose of this study was to evaluate the safety and diagnostic performance of CT-guided core needle biopsy (CNB) of pulmonary lesions associated with cystic airspaces. METHODS. This retrospective study included 90 patients (median age, 69.5 years; 28 women, 62 men) who underwent CT-guided CNB of pulmonary lesions associated with cystic airspaces (based on review of procedural images) from February 2010 to December 2022 and a matched control group (2:1 ratio) of 180 patients (median age, 68.0 years; 56 women, 124 men) who underwent CNB of noncystic noncavitary lesions during the same period. The groups were compared in terms of complications, nondiagnostic biopsies (i.e., nonspecific benignities, atypical cells, or insufficient specimens), and CNB diagnostic performance for detecting malignancy using as reference the final diagnosis from a joint review of all available records. For lesions associated with cystic airspaces that underwent surgical resection after CNB, histologic slides were reviewed to explore the nature of the cystic airspace. RESULTS. The final diagnosis was malignant in 90% (81/90) of lesions associated with cystic airspaces and 92% (165/180) of noncystic noncavitary lesions. Patients with lesions associated with cystic airspaces and patients with noncystic noncavitary lesions showed no significant difference in frequency of complications (overall: 40% [36/90] vs 38% [68/180], p = .79; major: 4% [4/90] vs 6% [10/180], p = .78; minor: 36% [32/90] vs 32% [58/180], p = .59), frequency of nondiagnostic biopsies (12% [11/90] vs 9% [16/180], p = .40), or diagnostic performance (accuracy: 94% [85/90] vs 97% [175/180], p = .50; sensitivity: 94% [76/81] vs 97% [160/165], p = .50; specificity: 100% [9/9] vs 100% [15/15]; p > .99), respectively. All false-negative results for malignancy in both groups occurred in patients with nondiagnostic CNB results. Among lesions associated with cystic airspaces that were resected after CNB (all malignant), the cystic airspaces most commonly represented tumor degeneration (22/31 [71%]). CONCLUSION. CT-guided CNB is safe and accurate for assessing pulmonary lesions associated with cystic airspaces. CLINICAL IMPACT. CNB may help avoid a missed or delayed cancer diagnosis in pulmonary lesions with cystic airspaces.