Role of Endoscopic Ultrasound in Diagnosis of Rectal and Perirectal Lesions | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Afro-Egyptian Journal of Infectious and Endemic Diseases | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Article 10, Volume 12, Issue 1, March 2022, Page 75-84 PDF (415.61 K) | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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DOI: 10.21608/aeji.2022.107763.1193 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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Authors | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Zainab G Mahran1; Sherif I Kamel1; Hussein H Okasha2; Ahmed M Ashmawy 3; Mohammed Ezz-Eldin 1 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
1Department of Tropical Medicine and Gastroenterology, Faculty of Medicine, Assiut University, Assiut, Egypt. | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
2Department of Internal Medicine, Division of Gastroenterology, Kasr Al-Aini School of Medicine, Cairo University, Cairo, Egypt. | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
3Gastroenterology and Hepatology Unit, Department of Internal Medicine, Faculty of Medicine, Assiut University, Assiut, Egypt. | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Abstract | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Background and study Aim: Endoscopic ultrasound (EUS) demarcates several layers of the gastrointestinal wall, with little reports about its use as a diagnostic modality for rectal and perirectal lesions. So, we aimed to evaluate its role in diagnosis of rectal and perirectal lesions. Patients and Methods: During the period between 2017 and 2019, a cross-sectional study was done. Seventy adult patients included in the study who had rectal and/or perirectal lesions. All the 70 patients had rectal EUS. Out of the 70 patients, EUS-FNA was performed for 26 patients where it was possible and the wall was thick enough to allow for sampling (>7mm). Results: Mean age of the study population was 51.91 ± 9.90 years, with a range of age between 26 and 69 years. There was a perfect agreement (Kappa Agreement = 1) with statistically significant difference between EUS diagnosis, EUS-FNA diagnosis and final diagnosis. There was a perfect agreement (Kappa Agreement = 0.97) with statistically significant difference between presumptive diagnosis and final diagnosis. Our study showed a relationship between EUS elastography and the final diagnosis of the lesions where soft pattern corresponded to most of the benign cases (67.60%) and firm pattern corresponded to most of the malignant cases (78.70%). Conclusion: EUS is a useful diagnostic tool for rectal and perirectal lesions . | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Highlights | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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Keywords | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Elasticity imaging Techniques; Endosonography; Rectum; Biopsy; Fine-Needle | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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INTRODUCTION Because of its capability to discriminate multiple layers of the gastrointestinal (GI) wall, endoscopic ultrasound (EUS) has become a valuable tool for evaluating GI tract lesions and lesions near the GI tract. Although EUS is well-known for assessing pancreatic and upper GI tract lesions, its value as a diagnostic and staging tool for other parts of the GI tract, notably the recto-sigmoid colon, is becoming more frequently recognized [1, 2]. Even though EUS can correctly stage GI malignancies, it cannot reliably distinguish benign from malignant lesions on its own. As a result, pathologic testing is usually necessary to establish a definitive diagnosis for clinical intervention [3]. The ability to collect cytological material under direct vision has expanded the diagnostic performance of this procedure, allowing for a more precise diagnosis [4, 5]. Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) diagnostic accuracy for esophageal, gastric and duodenal subepithelial tumors has been reported to be 82–94% [6, 7] and 80–95% for pancreaticobiliary lesions [8, 9]. Few studies have looked at how useful EUS is as a diagnostic tool for rectal and perirectal pathologies. The relevance of EUS-FNA in assessing submucosal and extrinsic masses of the colon and rectum has been highlighted in several trials [10-13].Aim: Our study looked at role of EUS to assess nature of polyps and submucosal lesions and differentiate benign and malignant lesions in the rectal and perirectal areas. PATIENTS AND METHODS This cross-sectional prospective study included 70 adult patients (44 males and 26 females) with mean age of 51.91 ± 9.90 years and ranges from of 26 to 69 years. All patients had rectal and/or perirectal lesions detected either by abdominopelvic CT or MRI and/or colonoscopy. All the 70 patients underwent rectal EUS. Out of the 70 patients, EUS-FNA was performed for 26 patients if the wall thickness was sufficient for aspiration (> 7 mm). The patients selected from those attending the Internal Medicine Department during the period from June 2017 to May 2019. In this study, inclusion criteria according to the findings detected were:
Exclusion criteria were:
For all the patients included, the following assessment schedule applied:
Procedure: The patients were in a left lateral decubitus position. An EUS linear array machine (Pentax EG-3830UT Echoendoscope) attached to a compatible ultrasound machine (Hitachi EUB 7000 or Avius)were used. One expert endosonographer performed all EUS examinations. FNA was obtained under EUS guidance using fine needles (Cook Echotip needle) 22 or 19G. Elastography was done to assess the hardness of the lesions. To avoid puncturing intervening blood vessels, Doppler was utilized to assess the needle's predicted route. During EUS, all lesions were examined thoroughly including all layers of the rectal wall underneath the lesions. The presence of perirectal lymph nodes, depth of wall invasion and invasion into the perirectal fat or adjacent organs (such as the bladder, prostate, seminal vesicles, vagina or anal sphincters) were evaluated (figure 1). If it was feasible and the wall thickness was sufficient for aspiration, the FNA needle was progressed through the linear array echoendoscope's instrument channel, the gut wall punctured, the needle entered the lesion and reciprocated back and forth with a negative suction applied via a syringe of 10 mL once the internal stylet was removed. The needle was retracted then into the sheath before being removed from the scope. The internal stylet was introduced and the tissue material was extracted onto a slide using air injected with a syringe. The needle was pushed through the lesion once more after checking that the tissue material was sufficient. The procedure repeated for 1-4 times to provide sufficient samples. Processing of cytological samples: All cytological samples are processed and interpreted by experienced cytopathologists. The specimens were considered satisfactory when it contained an adequate population of representative cells. The aspirated samples expelled onto slides, and smears prepared. Then the remaining specimens, obtained from subsequent passing, were processed for cell-block evaluation. Outcome: The percentage of patients who had a proper diagnosis using EUS and cytopathological diagnosis from samples collected by EUS-FNA were measured. Before undergoing EUS, a presumptive diagnosis was determined based on the imaging and colonoscopy data. In patients who have had surgery, the final diagnosis was made based on cytopathological findings from resected specimens. Based on the long-term clinical course (at least six months) as well as the EUS-FNA results, the final diagnosis was reached in patients who did not have surgery. Statistical Analysis: Data verified, coded by the researcher, and analyzed using IBM-SPSS 21. Descriptive statistics: Means, standard deviations, medians, ranges, and percentages calculated. Test of significance: chi-square test used to compare the difference in distribution of frequencies among different groups. Kappa agreement calculated to explore the validity of the different diagnostic modalities against the final diagnosis where; a kappa of 0.01-0.20 = no/slight agreement, 0.21-0.40 = fair agreement, 0.41-0.60 = moderate agreement, 0.61-0.80 = good agreement, 0.81-1= perfect agreement (14). A significant p-value was considered when it is equal or less than 0.05. RESULTS: Demographics and Baseline Characteristics: Concerning medical history of studied cases, 50 (71.40%) had rectal pain, 37 (52.90%) had change in bowel habit, 40 (57.10%) had bleeding per rectum, 7 (10%) had weight loss, 33 (47.10%) had anemic manifestations, 3 (4.30%) had past history of cancer and 6 (8.60%) had family history of cancer (table 1). Concerning diagnosis made by colonoscopy of all the studied cases (N = 70), six (8.60%) were normal, 29 (41.40%) were benign and 35 (50%) were malignant. About presumptive diagnosis (imaging + colonoscopy) of all the studied cases (N = 70), 33 (47.10%) were benign and 37 (52.90%) were malignant. On the topic of EUS elastography of all lesions (N = 70), the score was two in 25 cases (35.70%), three in 13 cases (18.60%) and four in 32 cases (45.70%). Regarding the final diagnosis and diagnosis made by EUS for all cases (N = 70), 32 (45.70%) were benign and 38 (54.30%)were malignant (figure 2). Regarding the final diagnosis and diagnosis made by EUS-FNA for the selected cases (for whom FNA was done, N = 26), five cases (19.20%) were benign, and 21 cases (80.80%) were malignant (figure 3). Validity of Various Diagnostic Tools for Diagnosis of Malignancy: Regarding the validity of the EUS for diagnosis of malignancy in all studied cases (N = 70), there was a perfect agreement (Kappa Agreement = 1) with statistically significant difference (P < 0.001) between EUS diagnosis and final diagnosis (table 2 and 6). About the validity of the EUS-FNA for diagnosis of malignancy in the selected cases (N = 26), there was a perfect agreement (Kappa Agreement = 1) with statistically significant difference (P < 0.001) between EUS-FNA diagnosis and final diagnosis (table 3 and 6). Regarding the validity of the colonoscopy for diagnosis of malignancyin all studied cases (N = 70), there was a perfect agreement (Kappa Agreement = 0.91) with statistically significant difference (P < 0.001) between colonoscopy diagnosis and final diagnosis with some disagreement (table 4 and 6). About validity of the presumptive diagnosis (colonoscopy + imaging) for diagnosis of malignancy in all studied cases (N = 70), there was a perfect agreement (Kappa Agreement = 0.97) with statistically significant difference (P < 0.001) between presumptive diagnosis and final diagnosis with little disagreement (table 5 and 6). Relationship between EUS Elastography and the Final Diagnosis: As regards to the relationship between EUS elastography and the final diagnosis, 25 cases (35.70%) of benign lesions had score 2, seven cases (10%) of benign lesions and six cases (8.60%) of malignant lesions had score 3 and 32 cases (45.70%) of malignant lesions had score 4 with statistically significant difference (P < 0.001) (table 7). Table (1): Demographic characteristics and medical history of the studied cases.
Note: Data expressed in the form of frequency (percentage) or mean (standard deviation) as appropriate. N, number; SD, standard deviation. Table (2): Validity of the EUS for diagnosis of malignancy.
Note: Data expressed in the form of frequency (percentage) as appropriate. A significant p-value was considered when it is equal or less than 0.05. A kappa of 0.01-0.20 = no/slight agreement, 0.21-0.40 = fair agreement, 0.41-0.60 = moderate agreement, 0.61-0.80 = good agreement, 0.81-1 = perfect agreement. EUS, endoscopic ultrasound. Table (3): Validity of the EUS-FNA for diagnosis of malignancy.
Note: Data expressed in the form of frequency (percentage) as appropriate. A significant p-value was considered when it is equal or less than 0.05. A kappa of 0.01-0.20 = no/slight agreement, 0.21-0.40 = fair agreement, 0.41-0.60 = moderate agreement, 0.61-0.80 = good agreement, 0.81-1 = perfect agreement. EUS-FNA, endoscopic ultrasound-guided fine needle aspiration. Table (4): Validity of the colonoscopy for diagnosis of malignancy.
Note: Data expressed in the form of frequency (percentage) as appropriate. A significant p-value was considered when it is equal or less than 0.05. A kappa of 0.01-0.20 = no/slight agreement, 0.21-0.40 = fair agreement, 0.41-0.60 = moderate agreement, 0.61-0.80 = good agreement, 0.81-1 = perfect agreement. Table (5): Validity of the presumptive diagnosis (Imaging + Colonoscopy) for diagnosis of malignancy.
Note: Data expressed in the form of frequency (percentage) as appropriate. A significant p-value was considered when it is equal or less than 0.05. A kappa of 0.01-0.20= no/slight agreement, 0.21-0.40 = fair agreement, 0.41-0.60 = moderate agreement, 0.61-0.80 = good agreement, 0.81-1 = perfect agreement. Table (6): Performance characteristics of various diagnostic tools for diagnosis of malignancy.
Note: Data expressed in the form of percentage as appropriate. EUS, endoscopic ultrasound; EUS-FNA, endoscopic ultrasound-guided fine needle aspiration. Table (7): Relationship between EUS elastography and final diagnosis.
Note: Data expressed in the form of frequency (percentage) as appropriate. A significant p-value was considered when it is equal or less than 0.05. EUS, endoscopic ultrasound. DISCUSSION Although EUS may be used to outline the GI wall, there has been few research on the use of EUS to diagnose rectal and perirectal pathologies. As a result, rectal EUS continues to be underused, maybe due to a lack of knowledge and awareness of the procedure's worth. Our study aimed to confirm the utility of EUS in the diagnosis of rectal and perirectal lesions. Rectal EUS and EUS-FNA, according to our findings, are excellent diagnostic techniques that play an important role in patient care. When a malignant diagnosis is made in a clinically worrisome lesion, treatment can begin right once. Unwarranted surgery can be avoided by confirming a benign diagnosis on lesions with low clinical suspicions. Our study showed that both rectal EUS and EUS-FNA had a perfect diagnostic accuracy, sensitivity and specificity, whereas colonoscopy alone had a lower diagnostic accuracy of 88.50%, sensitivity of 88% and specificity of 89% because it missed some benign and malignant pararectal lesions. The diagnostic accuracy was improved to 93%, the sensitivity to 97%, and the specificity to 89% by adding an imaging modality to colonoscopy making a presumptive diagnosis. Previous EUS studies for the lower GI tract have similarly shown great diagnostic precision. Boo et al. [13] found EUS to be effective in rectal or perirectal lesions, with good diagnostic accuracy (91.70%). Amin et al. [15] found that EUS had a sensitivity and specificity of 91% and 100% for detecting malignant rectal/perirectal lesions, respectively. Maleki et al. [16] evaluated the use of rectal EUS to assess perirectal lesions and found that it had 87% sensitivity, 100% specificity, 90% diagnostic accuracy, 100% positive predictive value (PPV), and 77% negative predictive value (NPV). According to Puli et al. [17] meta-analysis and systematic review, the pooled sensitivity of EUS in diagnosing T0 was 97.30%, the pooled specificity was 96.30%, the positive likelihood ratio was 21.90 while the negative likelihood ratio was 0.08. Some previous trials have contradicted our findings. According to Soh et al. [18], EUS had a low diagnostic accuracy of 50% for subepithelial tumors (5/10), 75% for non-subepithelial tumors (15/20), and an overall diagnostic accuracy of 67% (20/30) for rectal and perirectal lesion. And according to Serra-Aracil et al. [19], the overall accuracy of EUS was 78%, with 83.78% sensitivity, 20% specificity, 91.30% PPV, and 11% NPV. Forty patients (8.08%) were under staged, whereas 50 (10.90%) were over staged. The capacity to assess tissue elasticity makes elastography an extension of clinical sense, reinforcing and validating the diagnosis. There are, however, few research on the use of EUS elastography to distinguish benign from malignant rectal tumors. Our study showed that there was a relationship between EUS elastography and the final diagnosis of the lesions. Soft pattern (grades 1 and 2) corresponded to most of the benign cases (67.60%) and firm pattern (grades 3 and 4) corresponded to most of the malignant cases (78.70%). Additional advantage of EUS is that it is quite safe, with a minimal risk of serious complications. In all the cases in which we studied it; the technique had no adverse effects. Our work had some limitations; (1) Relatively small sample size (2) There were no on-site cytopathologists for all cases. (3) There was a problem in fixing specific imaging modality (e.g., MRI). (4) Restricted ability of rectal EUS examination to evaluate for the lymph nodes in the region of the left iliac vessels. Various advanced technologies to enhance ultrasound imaging and therapeutic indications may contribute to the expanded utility of rectal EUS. Future multicenter studies with large sample sizes on the relevance of EUS and elastography in the evaluation of rectal and perirectal lesions are needed. Comparative studies between EUS and imaging techniques, particularly MRI, might be prepared in the diagnosis of rectal and perirectal lesions. CONCLUSION EUS is a useful diagnostic technique evaluating rectal and perirectal lesions; it confirms or rules out malignancy in lesions when clinical suspicion exists. On the condition that the endosonographer has a lot of expertise with endosonography, EUS alone without FNA may be enough to diagnose rectal and perirectal abnormalities. The use of EUS elastography in the identification and distinction of benign and malignant rectal and pararectal lesions could be valuable. Source(s) of support: none Presentation at a meeting: no Conflicting Interest: no Ethical Considerations: The study performed after being approved from the Institutional Review Board (IRB) of Faculty of Medicine with an IRB number of 17200593. The study was conducted in accordance with the provision of Declaration of Helsinki. Privacy of the participants as well as confidentiality of the data assured. Patients informed about the possible side effects and complications that may happen within the procedure. Informed consents, telephone numbers, and addresses were taken from the patients. | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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