Subepithelial Lesions Research Articles

Endoscopic sutured purse-string resection: a novel technique for resection of large gastric subepithelial lesions.

Endoscopic sutured purse-string resection: a novel technique for resection of large gastric subepithelial lesions.

Efficacy and histologic frequencies of endoscopic ultrasonography‐guided tissue acquisition using conventional fine‐needle aspiration needles for gastric subepithelial hypoechoic mass

AbstractIntroduction/PurposeFor gastric subepithelial lesions (GSELs) showing a hypoechoic mass (HM) on endoscopic ultrasonography (EUS) imaging, the utility of EUS‐guided tissue acquisition using conventional fine‐needle aspiration needles (EUS‐TA‐CFNAN) and the frequency of histological types remain unclear. This study aimed to examine this issue.MethodsThis prospective observational study enrolled 291 consecutive patients who underwent EUS‐TA‐CFNAN for GSELs showing an HM (GSELHM) on EUS imaging. Immunohistochemical analysis was performed for all EUS‐TA‐CFNAN and surgically resected specimens. The main outcome measures were the technical results of EUS‐TA‐CFNAN and the frequency of histological types in GSELHM.ResultsThe endoscopic ultrasound‐guided tissue acquisition using conventional fine‐needle aspiration needle diagnosis rate for GSELHM was 80.1% (95% confidence interval [CI]: 75.0–84.5, 233/291). It was significantly lower for antrum (P = 0.004) and lesions smaller than 2 cm (P = 0.003). There were no adverse events. The immunohistochemical diagnoses of EUS‐TA‐CFNAN included 149 cases of gastrointestinal stromal tumour (GIST) (51.2%), 48 cases of leiomyoma (16.5%), 11 cases of schwannoma (3.8%), 8 cases of the ectopic pancreas (2.7%), 5 cases of subepithelial lesion like cancer (1.7%), 12 cases of other lesions (4.1%), and 58 cases of undiagnosable lesions (19.9%). The frequency of malignant or potentially malignant tumour in GSELHM was 55.0% (95% CI: 49.1–60.8, 160/291). Surgery was performed in 149 patients according to the conclusive EUS‐TA‐CFNAN results, in which the diagnostic accuracy of EUS‐TA‐CFNAN was 97.3% (95% CI: 94.7–99.9, 145/149).ConclusionThe use of EUS‐TA‐CFNAN for GSELHMs is safe and accurate. Gastric subepithelial lesions showing a hypoechoic mass have a reasonably high possibility of containing malignant or potentially malignant tumours, including GISTs.

The advent of the first electric driven EUS-guided 17 gauge core needle biopsy – A pilot study on subepithelial lesions

Background and aims This pilot study aimed to evaluate safety and tissue sampling from subepithelial lesions (SEL) in the upper gastrointestinal tract with a novel electric motor driven endoscopic ultrasonography (EUS)-guided 17-gauge (G) size core needle biopsy (CNB) instrument. Methods An investigator-led prospective open label, performance and safety control study, including seven patients (female n = 4, median 71 y, range 28–75) with a determined SEL (median size 30 mm, range 17–150 mm) in the upper digestive tract (stomach n = 6, duodenum n = 1) were eligible and later followed up 14 days after index procedure. All investigations were completed according to protocol with three FNB 22-G passes with four fanning strokes and two EndoDrill® 17-G passes with three fanning strokes. Results Quality of samples as ‘visible pieces’ (>5 mm): FNB (n = 5/7) (fragmented/blood imbibed n = 1, poor tissue quantity n = 1) compared with 17-G CNB (n = 7/7). Histological result which led to final diagnosis (leiomyoma n = 2, adenocarcinoma n = 1, schwannoma n = 1, neuroendocrine tumour n = 1, desmoid tumour n = 1 and gastrointestinal stromal tumour (GIST) n = 1) could be obtained with the 17-G CNB instrument in all seven patients. FNB technique reached correct diagnosis in six patients. No serious adverse event were recorded. Conclusions By using an electric driven 17-G biopsy device, a true cylinder of core tissue can be obtained in one single puncture from the area of interest reducing the need for a second sampling. The absolute benefit of EUS-guided CNB is that the sample can be handled and histologically prepared in the same manner as standard percutaneous core needle sample, e.g., breast and prostate cancer.

Transrectal contrast-enhanced ultrasound-guided transperineal core-needle biopsy versus endoscopic forceps biopsy in the diagnosis of complex rectal lesions.

The preoperative pathological diagnosis of rectal lesions is crucial for formulating treatment plans. For subepithelial lesions (SELs) and larger lesions with necrosis of the rectum, endoscopic forceps biopsy (EFB) cannot provide an accurate pathological diagnosis in most cases. By comparing the efficacy and safety of transrectal contrast-enhanced ultrasound-guided transperineal core-needle biopsy (TRCEUS-TP-CNB) and EFB, this study explored the value of TRCEUS-TP-CNB in the diagnosis of complex rectal lesions, such as SELs. A retrospective, cross-sectional study was conducted with 32 consecutive patients with complex rectal lesions admitted to our hospital from May 2016 to June 2022. Clinical, ultrasound, and pathological data were collected from these patients who underwent EFB followed by TRCEUS-TP-CNB. The success rate of EFB was 21.88% (7/32) and that of TRCEUS-TP-CNB was 93.75% (30/32). No significant complications were observed for either biopsy method. Factors affecting the success rate of EFB included the lesion width (cm) (1.90±0.62 vs. 4.26±2.40, P<0.001) and lesion thickness (cm) (1.29±0.51 vs. 2.96±1.75, P<0.001). The success rate of TRCEUS-TP-CNB was not affected by these factors. In the paired study of TRCEUS-TP-CNB and EFB, the times of samples per person (1 vs. 2.14±0.90, P=0.015), number of specimens per sample (8.27±1.93 vs. 3.31±1.67, P<0.001), lesion width (cm) (3.79±2.42 vs. 1.90±0.62, P=0.001), and lesion thickness (cm) (2.64±1.75 vs. 1.29±0.51, P=0.001) were the factors affecting the difference of the sampling success rate. In the SELs, the success rate of EFB was 10% (1/10) and that of TRCEUS-TP-CNB was 100% (10/10), and the difference between the two groups was statistically significant (P=0.004). TRCEUS-TP-CNB is an effective biopsy method for complex rectal lesions. The success rate of EFB is lower in the larger lesions. Compared with EFB, TRCEUS-TP-CNB required fewer times of samples be taken and obtained more specimens. For larger lesions and SELs of the rectum, TRCEUS-TP-CNB is expected to become one of the preferred biopsy methods.

Role of Endoscopic Ultrasonography (EUS) in Diagnosis of Subepithelial Lesions (SELS)

Role of Endoscopic Ultrasonography (EUS) in Diagnosis of Subepithelial Lesions (SELS)

Potential for expanded application of endoscopic hand suturing: A pilot study of 15 cases.

Endoscopic hand suturing (EHS) was first developed to firmly close a mucosal defect following endoscopic submucosal dissection and has the potential for expanded applications. This study aimed to investigate the feasibility and safety of EHS in various clinical settings. In this single-center pilot study, 15 patients who had diseases with potential indications for EHS were prospectively recruited. Technical success, clinical success after the procedure, and severe EHS-related adverse events (AEs) were evaluated. EHS was applied for defect closure after gastric subepithelial lesion removal under laparoscopic observation (n = 9), defect closure after rectal endoscopic full-thickness resection (EFTR) (n = 2), defect closure after thoracoscopy-assisted esophageal EFTR (n = 1), mucosal closure for gastric ulcer bleeding (n = 1), mucosal closure after peroral endoscopic myotomy (POEM) (n = 1), and postoperative anastomotic leak (n = 1). EHS was completed without severe AEs and the clinical courses were also favorable in 13 patients (87%). The median suturing time was 61 minutes. In patients with POEM and anastomotic leak, EHS was discontinued because of the narrow lumen. In conclusion, EHS appears feasible and safe in situations.

Feasibility and clinical value of linear endoscopic ultrasonography imaging in the lower gastrointestinal subepithelial lesions.

Linear endoscopic ultrasonography (EUS) has been extensively utilized as a novel diagnostic and therapeutic modality across various fields. However, there have been relatively few studies focusing on lower gastrointestinal lesions. The aim of our study was to investigate the feasibility, safety and clinical value of linear EUS in the lower gastrointestinal subepithelial lesions. This was a retrospective study involving patients with lower gastrointestinal subepithelial lesions diagnosed by linear EUS from August 2019 to April 2023 at the Second Affiliated Hospital of Anhui Medical University. The data, including basic clinical information, linear EUS features, technical success rate, complications, and follow-up, were retrospectively collected and analyzed. A total of 69 patients with lower gastrointestinal subepithelial lesions underwent examination by linear EUS. Excluding the rectum, the technical success rate of linear EUS was 90.6% (29/32). Apart from the 7 patients whose diagnosis remained unknown, 3 patients with no abnormal EUS findings, and 3 patients failed the procedure, 56 patients were included in the final diagnostic performance analysis. The most common locations of the lesions were the rectum (37/56, 66.1%) and sigmoid colon (7/56, 12.5%). Based on endoscopy findings and pathological results, the most prevalent types of subepithelial lesions in the lower gastrointestinal tract were neuroendocrine tumor (NET) (12/56, 20.3%), lipoma (8/56, 13.6%) and extraluminal compression (8/56, 13.6%). The majority of lesions ranged in diameter from 1 to 3cm (χ2 = 18.750, p < 0.001). After undergoing linear EUS examination, 36 patients received EUS-FNA (3/36), biopsy (5/36), endoscopic resection (25/36), or surgical excision (3/36) respectively. The pathological results of 29 patients were entirely consistent with the diagnosis made using linear EUS, with an 80.6% (29/36) diagnostic accuracy rate. Follow-up indicated that the lesions remained unchanged within 6-36months. All patients tolerated the procedure well without any complications. In conclusion, linear EUS demonstrates technical feasibility, safety, and a high diagnostic accuracy for subepithelial lesions in the lower gastrointestinal tract.

Compression from a retroperitoneal schwannoma presenting as a subepithelial lesion of the gastric fundus.

Compression from a retroperitoneal schwannoma presenting as a subepithelial lesion of the gastric fundus.

Clinical course of small gastric subepithelial lesion less than 20mm diagnosed by endoscopic ultrasound-guided fine-needle aspiration.

Gastrointestinal stromal tumors (GISTs) are treated as malignant gastric subepithelial lesions (SELs), and resection is recommended. However, small gastric SELs <20mm with no malignant features are monitored without histopathological examination, and the frequency of malignancy is unknown. This study aimed to clarify the clinicopathological findings and clinical course of gastric SELs <20mm measured by endoscopic ultrasound (EUS). This retrospective cohort study included consecutive patients with small gastric SELs <20mm diagnosed using EUS at a tertiary referral center between 2009 and 2021. The clinical course after diagnosis using EUS-guided fine-needle aspiration (EUS-FNA) was reviewed. Among 333 patients with small gastric SELs, 104 patients with 105 lesions underwent EUS-FNA. The pathological diagnosis was confirmed in 87 patients. GISTs were the most common pathology (47%). Among the 87 patients, 43 underwent therapeutic interventions, including tumor resection and chemotherapy. In groups of tumor resection, the pathological tumor size on the resected specimen was significantly larger than the size measured by EUS (19.5mm vs 15.0mm, P<0.001), and 37% of resected SELs were 20mm or over. No recurrence was observed after tumor resection during a mean follow-up period of 40months. Approximately 40% of small gastric SELs were malignant tumors, such as GIST, with most of them requiring treatment. Additionally, considering that the EUS measurement is 5mm smaller than the pathological tumor diameter, further examinations, such as systematic EUS-FNA, may be required for SEL, including those smaller than 20mm.

Consensus statements on endoscopic ultrasound-guided tissue acquisition. Guidelines from the Asian Endoscopic Ultrasound Group.

This consensus was developed by the Asian EUS Group (AEG), who aimed to formulate a set of practice guidelines addressing various aspects of endoscopic ultrasound-guided tissue acquisition (EUS-TA). The AEG initiated the development of consensus statements and formed an expert panel comprising surgeons, gastroenterologists, and pathologists. Three online consensus meetings were conducted to consolidate the statements and votes. The statements were presented and discussed in the first two consensus meetings and revised according to comments. Final voting was conducted at a third consensus meeting. The Grading of Recommendations, Assessment, Development, and Evaluation system was adopted to define the strength of the recommendations and quality of evidence. A total of 20 clinical questions and statements regarding EUS-TA were formulated. The committee recommended that fine-needle biopsy (FNB) needles be preferred over conventional fine-needle aspiration (FNA) needles for EUS-TA of subepithelial lesions. For solid pancreatic masses, rapid on-site evaluation is not routinely recommended when FNB needles are used. For dedicated FNB needles, fork-tip and Franseen-tip needles have essentially equivalent performance. This consensus provides guidance for EUS-TA, thereby enhancing the quality of EUS-TA.

Second-look upper endoscopy as the initial approach to subepithelial lesions: a reassuring and reliable strategy.

Although endoscopic ultrasound (EUS) plays a critical role in the management of subepithelial lesions (SEL) of upper gastrointestinal tract many can be classified solely by a thorough upper gastrointestinal endoscopy (UGE) which can reduce the burden of additional studies. Analyze the impact of a stepwise approach starting with a second-look UGE before the decision of EUS in patients referred to our center with suspected SEL. Retrospective cohort study which included all adult patients referred to our center between 2015 and 2020 with suspected SEL.Second-look UGE evaluated the location, size, color, surface characteristics, movability and consistency of the SEL and bite-on-bite biopsies were performed. Decisions on SEL management and follow-up were collected. A total of 193 SEL (190 patients) were included. At the index-UGE, stomach was the most frequent location (n = 115;59.6%). Most patients performed a second-look UGE (n = 180; 94.7%). A minority was oriented directly to EUS (n = 8;4.2%) or endoscopic resection (n = 2; 1.1%). In patients who underwent a second-look UGE, SEL were excluded in 25 (13.9%) and 21 (11.7%) did not need further work-up. The remaining patients were submitted to EUS (n = 88;48.9%), surveillance by UGE (n = 44; 24.4%) or endoscopic resection (n = 2; 1.1%). Systematically performing a second-look UGE, in patients referred with suspected SEL, safely preclude the need for subsequent investigation in approximately one-fourth of the patients. As UGE is less invasive and more readily available, we suggest that a second-look UGE should be the initial approach in SEL management.

The diagnosis and surgery of small intestine duplication in 11-years girl

There is presented the clinical report of the diagnosis and surgical treatment of such rare malformation as tubular duplication of the small intestine in an 11-years girl. Clinical manifestations were intense abdominal pain and intestinal bleeding of unknown origin. Video capsule enteroscopy (VCE) made it possible to identify the pathological area and determine its location. The article presents modern ideas about duplication of the small intestine. There are indicated diagnostic methods and signs to allow suspecting this malformation. The possibilities and criteria for VCE in diagnosing subepithelial lesions and identifying the source of intestinal bleeding are described.

Endoscopic ultrasonography-related diagnostic accuracy and clinical significance on small rectal neuroendocrine neoplasms.

This research aimed to examine the diagnostic accuracy and clinical significance of endoscopic ultrasonography (EUS) in the context of small rectal neuroendocrine neoplasms (NENs). A total of 108 patients with rectal subepithelial lesions (SELs) with a diameter of < 20 mm were included in the analysis. The diagnosis and depth assessment of EUS was compared to the histology findings. The prevalence of NENs in rectal SELs was 78.7% (85/108). The sensitivity of EUS in detecting rectal NENs was 98.9% (84/85), while the specificity was 52.2% (12/23). Overall, the diagnostic accuracy of EUS in identifying rectal NENs was 88.9% (96/108). The overall accuracy rate for EUS in assessing the depth of invasion in rectal NENs was 92.9% (78/84). Therefore, EUS demonstrates reasonable diagnostic accuracy in detecting small rectal NENs, with good sensitivity but inferior specificity. EUS may also assist physicians in assessing the depth of invasion in small rectal NENs before endoscopic excision.

Spectrum of endoscopic gastric subepithelial lesions encountered on EUS-FNA: A single center experience.

Endoscopic ultrasound guided fine needle aspiration (EUS-FNA) is a minimally invasive and reliable non-surgical technique for the diagnosis of gastrointestinal lesions. The present study aimed to evaluate the spectrum of lesions encountered in the gastric subepithelium on EUS-FNA at a tertiary care center. Archival data of all patients undergoing EUS-FNA for gastric submucosal lesions over a period of 5 years was retrieved. Patient demographics, clinical presentation, and EUS findings were recorded along with the FNA results. A total of 78 EUS-FNA samples were analyzed. Material was adequate in 62 cases (79.48%) and inadequate in 16 cases (12.82%) patients due to scant cellularity. Of the adequate samples, 34 (43.5%) were reported as neoplastic while 20 (25.64%) were non-neoplastic, and 8 (10.25%) were reported as suspicious of a neoplasm. In the neoplastic category, the predominant diagnosis was of spindle cell neoplasm comprising gastrointestinal stromal tumor (13), benign neural tumor (03), leiomyoma (02), and spindle cell tumors (03). The latter could not be categorized further due to a lack of IHC material. The next common diagnosis was adenocarcinoma (06) followed by neuroendocrine tumor (02) and poorly differentiated carcinoma (01). The non-neoplastic lesions included non-specific pathology (15), inflammatory lesions (08), and one case each of tuberculosis, pancreatic rest, and Brunner gland hamartoma. Cell blocks for ancillary testing were available in 54 cases (65.23%) and follow-up was available in 42 cases (53.84%). EUS-FNA is a good modality for the diagnosis of gastric submucosal lesions with a high diagnostic yield.

Prone Jack-Knife Transanal Minimally Invasive Surgery: A Safe and Effective Approach for Anterior Low Rectal GI Stromal Tumors.

Subepithelial rectal lesions, including gastrointestinal stromal tumours (GIST), leiomyomas, neuroendocrine tumours, lipomas, and schwannomas, are rare surgical conditions. 1 Surgical management in this region often entails radical surgical excisions with stoma creation. Radical surgical excisions with stoma creation are often required for surgical management in this region. In this video, we demonstrate a transanal minimally invasive surgery (TAMIS) approach to anterior low rectal GIST. Patient underwent neoadjuvant Imatinib Mesylate after multidisciplinary team discussion, and were evaluated preoperatively with colonoscopy, pelvis MRI, and endoscopic ultrasound-guided tissue biopsy. 2,3 The procedure was performed with the patient in the prone jack-knife position and using the GelPOINT® Path transanal access, providing an excellent surgical platform. 4 The access channel was chosen based on the lesion's location from the anal verge, and ports were placed in a triangular fashion onto the GelSeal Cap, including an apex 10 mm sleeve for the telescope connected to the insufflation stabilization bag, two lower 10 mm working ports, and an additional port if traction was necessary. The RapidVac TM smoke evacuator was used for smooth surgery without fluctuating the surgical field and to achieve optimal vision. Dissection was initiated over the lower margin of the mass into the subepithelial plane and then performed along and around the mass in the desired plane. This approach and positioning in prone jack-knife, allowed dissection under direct vision with excellent surgical ergonomics and avoided radical resection. Our video demonstrates the feasibility and safety of TAMIS for the management of anterior low rectal subepithelial lesion, providing an alternative to more radical surgical approaches. See Video Vignette.

Implementation of esophageal endoscopic submucosal dissection in Spain: Results from the nationwide registry

Introduction and aimsThe outcomes of endoscopic submucosal dissection (ESD) in the esophagus have not been assessed in our country. Our primary aim was to analyze the effectiveness and safety of the technique. Material and methodsAnalysis of the prospectively maintained national registry of ESD. We included all superficial esophageal lesions removed by ESD in 17 hospitals (20 endoscopists) between January 2016 and December 2021. Subepithelial lesions were excluded. The primary outcome was curative resection. We conducted a survival analysis and used logistic regression analysis to assess predictors of non-curative resection. ResultsA total of 102 ESD were performed on 96 patients. The technical success rate was 100% and the percentage of en-bloc resection was 98%. The percentage of R0 and curative resection was 77.5% (n = 79; 95% CI: 68%–84%) and 63.7% (n = 65; 95% CI: 54%–72%), respectively. The most frequent histology was Barrett-related neoplasia (n = 55 [53.9%]). The main reason for non-curative resection was deep submucosal invasion (n = 25). The centers with a lower volume of ESD obtained worse results in terms of curative resection. The rate of perforation, delayed bleeding and post-procedural stenosis were 5%, 5% and 15.7%, respectively. No patient died or required surgery due to an adverse effect. After a median follow-up of 14 months, 20 patients (20.8%) underwent surgery and/or chemoradiotherapy, and 9 patients died (mortality 9.4%). ConclusionsIn Spain, esophageal ESD is curative in approximately two out of three patients, with an acceptable risk of adverse events.

A fast regional convolutional neural network system for the diagnosis of gastrointestinal subepithelial lesions on endoscopic ultrasound images.

A fast regional convolutional neural network system for the diagnosis of gastrointestinal subepithelial lesions on endoscopic ultrasound images.

Endoscopic ultrasound-guided biopsy using a three-prong asymmetry tip needle for pancreatic tumors and peridigestive tract lesions: Retrospective single-center study.

Endoscopic ultrasound-guided tissue acquisition is vital for diagnosing pancreatic and peridigestive tract lesions. A new three-prong asymmetry tip needle has been developed for this procedure. In this study, we retrospectively assessed the diagnostic ability, tissue collection volume, and procedural adverse events of the three-prong asymmetry tip needle for solid pancreatic, subepithelial, and other organ lesions. We analyzed the data of 58 consecutive patients who underwent endoscopic ultrasound-guided tissue acquisition using a three-prong asymmetry tip needle between August 2022 and April 2023 at a single care center. The tissue collection rate was 91.4% with 89.7% accuracy, 89.3% sensitivity, 100% specificity, 100% positive predictive value, and 25% negative predictive value. No significant differences in collection rates or diagnostic performance were observed based on the target organ, puncture route, or lesion size. Using our original assessment method, the average histological core tissue score was 3.1 ± 0.8, whereas the blood contamination volume was 2.5 ± 0.8. Only one of 58 patients (1.7%) developed a pancreatic fistula of moderate severity as an adverse event. The three-prong asymmetry tip needle demonstrated good diagnostic capability and adequate sample volume with safety for pancreatic, subepithelial, and other organ lesions.

Diagnostic yield and utility of boring biopsy for subepithelial lesions of the stomach and esophagus

Herein, we aimed to examine the diagnostic yield and utility of boring biopsy for subepithelial lesions (SEL) of the stomach and esophagus. A total of 52 patients with SELs of the stomach or esophagus underwent boring biopsy. The diagnostic yield of boring biopsy for gastric and esophageal SELs was 50% (21/42) and 80% (8/10), and for SELs with a diameter of less than 10mm, the diagnostic yield was 67% (6/9) and 83% (5/6), respectively. Forty-three percent (9/21) of the gastric SELs were diagnosed with gastrointestinal stromal tumor (GIST), while all esophageal SELs (8/8) were leiomyomas. Ten percent (4/42) of boring biopsies for the stomach were accompanied by complications:two cases of perforation and two of bleeding.

Analysis of computerized tomography characteristics in gastrointestinal subepithelial lesions diagnosed through endoscopy or endovascular ultrasound

Aim: Subepithelial lesions (SEL) of the gastrointestinal tract are lesions arising from the mucosa, submucosa or muscularis propria. This study is aimed to asses diagnostic characteristics of SELs on computerized tomography (CT) and to present the localization, size, CT attenuation and contrast enhancement patterns of the lesions that may aid in making correct diagnosis. Materials and Methods: Between December 2022 and March 2024, patients with a preliminary diagnosis of SEL on endoscopy or EUS and who underwent abdominal CT were retrospectively screened from the hospital database. Localization, size, pre-contrast and post-contrast Hounsfield Unit (HU) values of the lesions, and pathologic diagnoses were recorded and compared in patients with SEL. Results: Pathologic diagnosis was available in 25 (23.4%) patients with SEL detected on CT. Among these, the most common lesion was gastrointestinal stromal tumors (GIST, 52%). In 22 (20.6%) patients, the lesion was not detected on CT. The lesions that could not be seen on CT were less than 2 cm in size. Gastrointestinal distension was insufficient in the majority of patients in whom the lesion could not be visualized on CT. While the HU values increased by approximately 3 times in patients diagnosed with neuroendocrine tumors (median [interquartile ranges] 36.5 [32 – 40] vs. 101.5 [81.5 – 127.5]; p = 0.068), the increase was approximately 2 times in those with GIST (30 [29 – 38] vs. 70 [57 – 77]; p=0.003). Conclusion: This study presents several CT characteristics and pitfalls that may aid correct diagnosis of SELs with CT. SELs smaller than 2 cm in size and located in cardia are more likely to be missed with CT. Adequate gastric distention is crucial in correct diagnosis.