The KRAS-Variant and Cetuximab in HPV-Positive Oropharyngeal Cancer in NRG/RTOG 1016

PURPOSE/OBJECTIVE(S)

NRG/RTOG 1016 was a non-inferiority phase III trial comparing radiation with cisplatin versus cetuximab monotherapy for patients with HPV-positive oropharyngeal squamous cell carcinoma (SCC). The trial did not meet the non-inferiority criteria for overall survival (OS) and had significantly worse progression-free survival (PFS) and locoregional failure (LRF) in patients treated with cetuximab. Based on prior evidence that HNSCC patients with a germ-line mutation in KRAS (the KRAS-variant) had a positive response to radiation with cisplatin plus cetuximab without increased toxicity, samples from RTOG 1016 were used to test the protocol-specified hypothesis that KRAS-variant patients will have better outcomes when receiving IMRT + cetuximab monotherapy compared to IMRT + cisplatin.

MATERIALS/METHODS

The KRAS-variant was tested in 562 samples at MiraDx, a CLIA-certified laboratory. OS, PFS, LRF, and distant metastases (DM) were as defined per the RTOG 1016 protocol, and hazard ratios (HRs) were estimated by (cause-specific) Cox models. Negative binomial regression was used to model the number of treatment-related acute and late (≤ and > 180 days from end of treatment, respectively) grade 3-5 adverse events. To assess the predictive role of the KRAS-variant, all models included KRAS, assigned treatment, and their interaction, with the interaction tested at two-sided 0.05. HRs and toxicity ratios are expressed as IMRT + cetuximab / IMRT + cisplatin.

RESULTS

The prevalence of the KRAS-variant was 16% with similar patient and tumor characteristics and well-balanced treatment arms for variant and non-variant patients. Median follow-up was 8.6 years. There was no significant interaction between KRAS and treatment for OS (p = 0.99), PFS (p = 0.56), LRF (p = 0.09), or DM (p = 0.19) (Table 1). In KRAS-variant patients the mean acute and late toxicity ratios were 0.53 (95% CI 0.36, 0.80) and 1.62 (95% CI 0.57, 4.62). In non-variant patients, the mean acute and late toxicity ratios were 0.80 (95% CI 0.67, 0.95) and 0.55 (95% CI 0.35, 0.87), respectively. The interaction of KRAS and treatment was not significant for acute (p = 0.07) or late toxicity (p = 0.07).

CONCLUSION

While this study does not directly refute prior evidence that KRAS-variant patients benefit from radiation + cisplatin and cetuximab, this study does not support the hypothesis that the KRAS-variant is a predictive biomarker of improved outcome in HPV+ oropharyngeal SCC patients treated with IMRT + cetuximab alone, and suggests that for KRAS-variant patients, potential benefits in LRF and acute toxicity with cetuximab may be offset by worse DM and worse late toxicity.

Retrospective study of preservation and transection of the round ligament of uterus during laparoscopic transabdominal preperitoneal inguinal hernia repair in adult women

PURPOSE

The processing of the round ligament of uterus in laparoscopic transabdominal preperitoneal (TAPP) repair of inguinal hernia in women has contended. This study aimed to explore whether there is any difference in the surgical outcome and postoperative complications between the two processing modalities, preservation, and transection of the round ligament of uterus, in adult female inguinal hernia patients undergoing TAPP.

METHODS

Retrospective analysis of 84 female patients (117 sides) who underwent TAPP in XXX Hospital from July 2013 to August 2022. Patient characteristics and technical details of the surgical procedure were collected and divided into two groups according to whether the round ligament of uterus was severed intraoperatively or not. There were 52 cases (77 sides) in the group with preservation of the round ligament of uterus and 32 cases (40 sides) in the group with transection of the round ligament of uterus, comparing the general condition, surgical condition, and the occurrence of postoperative related complications between the 2 groups.

RESULTS

The operative time for unilateral primary inguinal hernia was (129.2 ± 35.1) and (89.5 ± 42.6) minutes in the preservation and transection groups, respectively. There were no statistical differences between the two groups in terms of age, length of hospital stay, ASA, BMI, history of lower abdominal surgery, type and side of hernia, intraoperative bleeding, and time to surgery for primary bilateral hernia (P > 0.05). In addition, there was likewise no statistical difference in the occurrence of postoperative Clavien-Dindo classification, VAS, seroma, mesh infection, labia majora edema, chronic pain or abnormal sensation in the inguinal region, and hernia recurrence in the two groups as well (P > 0.05).

CONCLUSION

There is no evidence that the transection of the round ligament of the uterus during TAPP has an impact on postoperative complications in patients. However, given the important role of the uterine round ligament in the surgical management of patients with uterine prolapse and the high incidence of uterine prolapse in older women, hernia surgeons should also be aware of the need to protect the round ligament of uterus in older women.

[Genetic analysis of a family with hereditary hemorrhagic telangiectasia caused by endoglin gene mutation]

Objective: To explore the genetic characteristics of a family with hereditary hemorrhagic telangiectasia (HHT) caused by endoglin (ENG) gene mutations. Methods: A total of 17 individuals from a 3-generation HHT family attending the First Affiliated Hospital of Dali University were selected as the research subjects. Clinical data and familial disease status of the HHT family proband were collected. Whole exome sequencing technology was used to screen for suspected pathogenic genes in the proband, and Sanger sequencing was used for family validation. Results: The proband and her mother had recurrent epistaxis and skin mucosal telangiectasia, and enhanced CT scans of the chest of the proband and her mother, daughter, and cousin indicated the presence of varying degrees of pulmonary arteriovenous malformations. The results of the full exon sequencing results showed that the proband carried the ENG gene c.579_599del non-shift deletion mutation, and Sanger sequencing showed that the mother, daughter, and cousin carried the same mutation. Conclusion: ENG gene c.579_ 599del mutation may be the genetic basis of HHT in this family.

Bevacizumab biosimilar candidate TAB008 compared to Avastin® in patients with locally advanced, metastatic EGFR wild-type non-squamous non-small cell lung cancer: a randomized, double-blind, multicenter study

BACKGROUND

Bevacizumab (Avastin®) is a monoclonal antibody targeting the vascular endothelial growth factor (VEGF). Used alone or in combination with chemotherapy and/or immunotherapy, Avastin® has shown promising efficacy in many cancers. This study compared the efficacy and safety of TAB008 with Avastin® sourced from the EU (bevacizumab-EU), in patients with non-squamous non-small cell lung cancer (nsNSCLC).

METHOD

In this randomized, double-blind, multicenter, phase III similarity study, treatment naïve for metastatic lung cancer., EGFR wild-type, locally advanced, metastatic, or recurrent non-squamous, non-small cell, lung cancer (nsNSCLC) patients were enrolled and randomized (1:1) into TAB008 or Avastin® groups. Patients received TAB008 or Avastin® 15 mg/kg intravenously plus paclitaxel/carboplatin for 4-6 cycles followed by TAB008 or Avastin® 7.5 mg/kg until disease progression, unacceptable toxicity or death. The primary endpoint compared the objective response rate (ORR) within 6 cycles as read by an independent radiological review committee (IRRC). Secondary endpoints compared disease control rate (DCR) Within 6 cycles, duration of response (DoR), progression-free survival (PFS), a year overall survival rate (OSR), overall survival (OS), safety, immunogenicity, and steady-state pharmacokinetics.

RESULTS

A total of 549 nsNSCLC patients were enrolled (277 in TAB008 group and 272 in Avastin® group). In the full analysis set, ORRs were 55.957% for TAB008 and 55.720% for Avastin®, and the ORR ratio was 1 (90% CI 0.89-1.14), well within the predefined equivalence margin of 0.75-1.33. No significant differences were found in DCR within 6 cycles (95.703% vs 95.367%, p = 0.8536), DoR (8.17 vs 7.3 months, p = 0.3526), PFS (9.10 vs. 7.97 months, p = 0.9457), 1 year overall survival rate (66.2% vs 68%, p = 0.6793), or OS (20.4 vs 17.6 months, p = 0.6549). Serious adverse events (SAEs) occurred in 37.55% (104/277) of patients in the TAB008 group and 34.32% (93/271) in the Avastin® group. Anti-drug antibodies were reported in 3 of 277 (1.08%) TAB008 patients, and 5 of 271 (1.85%) Avastin® patients, neutralizing antibody (Nab) was positive in 1 patient on Avastin®, which became negative upon follow-up. The steady-state trough concentrations (Cssmin) were 106.13 μg/mL in TAB008 group and 96.03 μg/mL in Avastin® groups, with the treatment group ratio of LS geometric means fully contained within the bioequivalence limits of 80.00-125.00% (90% CI was 101.74-120.05%).

CONCLUSIONS

TAB008 is similar to Avastin® in terms of efficacy, safety, and pharmacokinetic parameters, with comparable immunogenicity.

TRIAL REGISTRATION

ClinicalTrials.gov number; NCT05427305.

[Pulmonary vein stenosis with pulmonary infarction secondary to primary mediastinal seminoma: a case report]

Pulmonary vein stenosis is a rare condition that is often underdiagnosed and misdiagnosed. The clinical and radiologic manifestations are unspecific such as cough, hemoptysis and pulmonary lesions and are therefore difficult to distinguished with pneumonia and tuberculosis. The present study is a successful case report of pulmonary vein stenosis and pulmonary infraction secondary to mediastinal seminoma. This case suggested that pulmonary vein stenosis should be considered when a mediastinal mass is accompanied by pulmonary opacites that cannot be explained by common causes such as infection.

The direct prognosis comparison of 125I low-dose-rate brachytherapy versus laparoscopic radical prostatectomy for patients with intermediate-risk prostate cancer

BACKGROUND

This study aims to compare the clinical outcomes after performing radical prostatectomy (RP) or low-dose-rate brachytherapy (LDR) for patients with intermediate-risk prostate cancer (IRPC).

METHODS

We performed a retrospective analysis on 361 IRPC patients who underwent treatment in Peking Union Medical College Hospital from January 2014 to August 2021, of which 160 underwent RP and 201 underwent Iodine-125 LDR. Patients were followed in clinic monthly during the first three months and at three-month intervals thereafter. Univariate and multivariate regression analyses were conducted to predict biochemical relapse-free survival (bRFS), clinical relapse-free survival (cRFS), cancer-specific survival (CSS), and overall survival (OS). Biochemical recurrence was defined using the Phoenix definition for LDR and the surgical definition for RP. The log-rank test was applied to compare bRFS between the two modalities, and Cox regression analysis was performed to identify factors associated with bRFS.

RESULTS

Median follow-up was 54 months for RP and 69 months for LDR. According to log-rank test, the differences of 5-year bRFS (70.2% vs 83.2%, P = 0.003) and 8-year bRFS (63.1% vs 68.9%, P < 0.001) between RP and LDR groups were statistically significant. Our results also indicated that there was no significant difference in terms of cRFS, CSS, or OS between the two groups. With multivariate analysis of the entire cohort, prostate volume ≤ 30 ml (P < 0.001), positive margin (P < 0.001), and percentage positive biopsy cores > 50% (P < 0.001) were independent factors suggestive of worse bRFS.

CONCLUSIONS

LDR is a reasonable treatment option for IRPC patients, yielding improved bRFS and equivalent rates of cRFS, CSS and OS when compared with RP.

[Activation of GABAergic neurons in the zona incerta accelerates anesthesia induction with sevoflurane and propofol without affecting anesthesia maintenance or awakening in mice]

OBJECTIVE

To explore the regulatory effects of GABAergic neurons in the zona incerta (ZI) on sevoflurane and propofol anesthesia.

METHODS

Forty-eight male C57BL/6J mice divided into 8 groups (n=6) were used in this study. In the study of sevoflurane anesthesia, chemogenetic experiment was performed in 2 groups of mice with injection of either adeno-associated virus carrying hM3Dq (hM3Dq group) or a virus carrying only mCherry (mCherry group). The optogenetic experiment was performed in another two groups of mice injected with an adeno-associated virus carrying ChR2 (ChR2 group) or GFP only (GFP group). The same experiments were also performed in mice for studying propofol anesthesia. Chemogenetics or optogenetics were used to induce the activation of GABAergic neurons in the ZI, and their regulatory effects on anesthesia induction and arousal with sevoflurane and propofol were observed; EEG monitoring was used to observe the changes in sevoflurane anesthesia maintenance after activation of the GABAergic neurons.

RESULTS

In sevoflurane anesthesia, the induction time of anesthesia was significantly shorter in hM3Dq group than in mCherry group (P < 0.05), and also shorter in ChR2 group than in GFP group (P < 0.01), but no significant difference was found in the awakening time between the two groups in either chemogenetic or optogenetic tests. Similar results were observed in chemogenetic and optogenetic experiments with propofol (P < 0.05 or 0.01). Photogenetic activation of the GABAergic neurons in the ZI did not cause significant changes in EEG spectrum during sevoflurane anesthesia maintenance.

CONCLUSION

Activation of the GABAergic neurons in the ZI promotes anesthesia induction of sevoflurane and propofol but does not affect anesthesia maintenance or awakening.

[A region-level contrastive learning-based deep model for glomerular ultrastructure segmentation on electron microscope images]

OBJECTIVE

We propose a novel region- level self-supervised contrastive learning method USRegCon (ultrastructural region contrast) based on the semantic similarity of ultrastructures to improve the performance of the model for glomerular ultrastructure segmentation on electron microscope images.

METHODS

USRegCon used a large amount of unlabeled data for pre- training of the model in 3 steps: (1) The model encoded and decoded the ultrastructural information in the image and adaptively divided the image into multiple regions based on the semantic similarity of the ultrastructures; (2) Based on the divided regions, the first-order grayscale region representations and deep semantic region representations of each region were extracted by region pooling operation; (3) For the first-order grayscale region representations, a grayscale loss function was proposed to minimize the grayscale difference within regions and maximize the difference between regions. For deep semantic region representations, a semantic loss function was introduced to maximize the similarity of positive region pairs and the difference of negative region pairs in the representation space. These two loss functions were jointly used for pre-training of the model.

RESULTS

In the segmentation task for 3 ultrastructures of the glomerular filtration barrier based on the private dataset GlomEM, USRegCon achieved promising segmentation results for basement membrane, endothelial cells, and podocytes, with Dice coefficients of (85.69 ± 0.13)%, (74.59 ± 0.13)%, and (78.57 ± 0.16)%, respectively, demonstrating a good performance of the model superior to many existing image-level, pixel-level, and region-level self-supervised contrastive learning methods and close to the fully- supervised pre-training method based on the large- scale labeled dataset ImageNet.

CONCLUSION

USRegCon facilitates the model to learn beneficial region representations from large amounts of unlabeled data to overcome the scarcity of labeled data and improves the deep model performance for glomerular ultrastructure recognition and boundary segmentation.

[Analysis of the pathogenesis and risk factors of gallstone]

Objective: To explore the pathogenesis and risk factors of gallstone formation. Methods: The findings of hepatobiliary ultrasound and related data were collected from healthy subjects who underwent a physical examination at Xuanwu Hospital of Capital Medical University from January 2012 to December 2021. A total of 98 344 healthy subjects were included in the study,including 48 241 males and 50 103 females,with a ratio of 1∶1.03,aged (42.0±15.6)years(range:14 to 97 years). The gender,age,body mass index,waist circumference,systolic pressure,diastolic pressure,ALT,AST,total bilirubin,fasting blood glucose,triglyceride,total cholesterol,low-density lipoprotein,high-density lipoprotein were collected.Healthy subjects were required to sit for at least 10 minutes before blood pressure was measured.Rresults of fasting venous blood were collected after 8 to 12 hours on an empty stomach.According to the presence of gallstones by ultrasound results, healthy subjects were divided into study group and control group. Data were analyzed by rank-sum tests and χ² test, and risk factors for gallstone formation were explored by Logistic regression analysis. Results: The incidence of gallstones in this group was 5.42%(5 333/98 344). Among them,the incidence of gallstones in people aged 60 years and above was significantly higher than that in people under 60 years old(15.31%(2 348/15 334) vs. 3.60%(2 985/83 010), χ²=3 473.46,P<0.05).The healthy subjects were divided by age for every 10 years,and the results showed that the incidence of gallstones increased with age. The incidence of gallstones in females was 5.68%(2 844/50 103),greater than 5.16%(2 489/48 241) in males(χ²=11.81,P<0.05). Among them,1 478 cases underwent gallbladder surgical resection due to gallstones,and the operation rate was 27.71%. The operation rate reached the peak between 60 and <70 years old,and decreased after 70 years old. The results of the multivariate analysis showed that,female(OR=1.38, P<0.01),age(OR=1.58, P<0.01),body mass index≥24 kg/m²(OR=1.31, P<0.01),waist circumference≥85 cm(OR=1.24, P<0.01),fasting blood glucose>6.1 mmol/L(OR=1.18,P<0.01),total cholesterol≥5.18 mmol/L(OR=0.87, P=0.019),low-density lipoprotein≥3.37 mmol/L(OR=1.15,P=0.001) were the risk factors for gallstone formation;high-density lipoprotein≥1.55 mmol/L(OR=0.87, P<0.01) was a protective factor for gallstone formation. Conclusions: The incidence of gallstones increases with age in male and female. Gender,age,body mass index,waist circumferenc,fasting blood glucose,total cholesterol,LDL,and HDL are related factors with gallstone formation.

Uniaxial cyclic stretch enhances osteogenic differentiation of OPLL-derived primary cells via YAP-Wnt/β-catenin axis

The pathogenesis of posterior longitudinal ligament ossification (OPLL) remains inadequately understood. Mechanical stimulation is one of the important pathogenic factors in OPLL. As one of the mechanical stimulation transduction signals, the yes-associated protein (YAP) interacts with the Wnt/β-catenin signalling pathway, which plays an important role in osteogenic differentiation. This study aimed to demonstrate the role of YAP-Wnt/β-catenin axis in cell differentiation induced by mechanical stress. Primary cells extracted from posterior longitudinal ligament tissues from OPLL or non-OPLL patients were subjected to sinusoidal uniaxial cyclic stretch (5 %, 0.5 Hz, 3 d). The expression of runt-related transcription factor 2, collagen I, osterix, osteocalcin and alkaline phosphatase were compared between the static and the experimental groups. In addition, the cytoskeleton was detected using phalloidin staining while YAP phosphorylation states and nuclear location were identified using immunofluorescence. The results showed that mechanical stretching loading increased the expression of osteogenic genes and proteins in the OPLL group, while it had no significant effect on the control group. When OPLL cells were stretched, YAP exhibited an obvious nuclear translocation and the Wnt/β-catenin pathway was activated. Knocking down YAP or β-catenin could weaken the impact upon osteogenic differentiation induced by mechanical stimulation. YAP-mediated mechanical stimulation promoted osteogenic differentiation of OPLL cells through Wnt/β-catenin pathway and this progress was independent of the Hippo pathway.

[Prevalence and molecular characterization of Cryptosporidium in captive-bred Mustela putorius furo in Jiangsu Province]

OBJECTIVE

To investigate the prevalence and molecular features of Cryptosporidium in captive-bred Mustela putorius furo in Jiangsu Province.

METHODS

A total of 290 fresh stool samples were collected from a ferret farm in Jiangsu Province on May 2017, and the small subunit rRNA (SSU rRNA) gene of Cryptosporidium was amplified in stool samples using nested PCR assay. The actin, cowp and gp60 genes were amplified in positive samples and sequenced to characterize Cryptosporidium species/genotypes.

RESULTS

A total of 18 stool samples were tested positive for Cryptosporidium SSU rRNA gene, with a detection rate of 6.2%. Sequence and phylogenetic analyses of SSU rRNA, actin and cowp genes characterized Cryptosporidium isolated from captive-bred ferrets as Cryptosporidium sp. ferret genotype. In addition, gp60 gene was amplified in 10 out of 18 stool samples tested positive for Cryptosporidium.

CONCLUSIONS

Cryptosporidium is widely prevalent in captive-bred ferrets in Jiangsu Province, and Cryptosporidium sp. ferret genotype is the only Cryptosporidium genotype in ferrets.

[Analysis of risk factors for decompensated cirrhosis complicated with sepsis]

Objective: To investigate the related risk factors in patients with decompensated cirrhosis complicated with sepsis. Methods: 1 098 cases with decompensated cirrhosis were collected from January 2018 to December 2020. A total of 492 cases with complete data meeting the inclusion criteria were included. Among them, the sepsis group (240 cases) was complicated with sepsis and the non-sepsis group (252 cases) was not complicated with sepsis. Albumin, cholinesterase, total bilirubin, prothrombin activity, urea, creatinine, international normalized ratio and other indicators of the two groups of patients were collected. Child-Pugh classification and MELD score were performed on two groups of patients. Mann-Whitney U test was used for non-normally distributed measurement data, and rank sum test for grade data. Logistic regression analysis was performed on sepsis-related factors that may affect patients with decompensated cirrhosis complicated with sepsis. Results: 162 cases of gram negative bacteria, 76 cases of gram positive bacteria and 2 cases of Candida were detected. Child-Pugh grade C was mainly in the sepsis group, and Child- Pugh grade A and B was mainly in the non-sepsis group (z=-13.01, P＜0.05). MELD score was significantly higher in patients with sepsis than that of patients without sepsis (z=-12.30, P＜0.05). Neutrophils percentage, C-reactive protein, procalcitonin, and total bilirubin in patients with decompensated cirrhosis complicated with sepsis were 86.90% (79.00%, 91.05%), 48.48 (17.63, 97.55) mg/l,1.34 (0.40, 4.52) ng/l, and 78.50 (32.75149.80) μmol/L, which were significantly higher than that of patients without sepsis [69.55% (58.58%, 75.90%), 5.34 (5.00, 14.94) mg/l, 0.11(0.06,0.24) ng/l, 22.50(15.10,37.55) respectively] μmol/L, P＜0.05], while the albumin level, prothrombin activity level, and the cholinesterase level in sepsis patients were 27.30 (24.45, 30.60) g/L, 46.00% (33.50%, 59.00%), and 1.87 (1.29, 2.66) kU/L, respectively, which was significantly lower than the non-sepsis group [32.65 (28.95, 37.23) g/l, 73.00(59.75～84.85)%, 3.13(2.23～4.59) kU/L, P＜0.05]. Logistic regression analysis showed that serum total bilirubin, albumin, prothrombin activity level and diabetes mellitus were the independent risk factors for complicated sepsis. Conclusion: Patients with decompensated cirrhosis with poor liver function and higher MELD scores are more likely to be complicated with sepsis. Therefore, during the clinical diagnosis and treatment course, patients with decompensated cirrhosis with poor liver reserve function should be actively and dynamically monitored for infection-related indicators such as neutrophil percentage, procalcitonin, C-reactive protein, in an attempt to detect possible potential infections and sepsis, and improve early treatment and prognosis.

Correlating Cytologic and Histologic Features of Hepatic Epithelioid Hemangioendothelioma

Introduction/Objective

Epithelioid hemangioendothelioma (EHE) is a rare malignant vascular tumor composed of epithelioid and dendritic tumor cells embedded in myxoid or hyalinized stroma. It can occur in various organs and has nonspecific clinical and radiologic presentation. We report a case of EHE in the liver with correlation of cytologic and histological findings.

Methods/Case Report

A 68-year-old female presented for evaluation of a right hepatic lobe lesion that was noted on Imaging. MRI abdomen with contrast showed a well-circumscribed hypointense nodule with no contrast enhancement. CT-guided fine needle aspiration showed scattered atypical epithelioid cells in a background of benign hepatocytes which were positive for vascular markers (CD31 and CD34) as well as keratins and SMA. A diagnosis of atypical vascular neoplasm was rendered. A partial hepatectomy was performed a month later which showed a 3.2 cm mass with solid tan-white cut surface. Histologically, the mass was composed of epithelioid tumor cells with focal intracytoplasmic vacuoles which were partly solid and partly forming vascular-like spaces, embedded in a background of hyalinized stroma. Immunohistochemically, in addition to the vascular markers the tumor was positive for CAMTA1 confirming the presence of WWTR1-CAMTA1 gene fusion which is characteristic for epithelioid hemangioendothelioma. The patient was discharged in good condition.

Results (if a Case Study enter NA)

NA.

Conclusion

Diagnosis of EHE on FNA is challenging. It is characterized by discohesive atypical large polygonal cells with abundant dense cytoplasm in a background of benign hepatocytes. Characteristically, the tumor cells have intracytoplasmic vacuoles containing red blood cells, which resemble signet ring-like structures. Immunohistochemically, positivity for vascular markers and CAMTA1 is diagnostic.

Elastotic Mass-Forming Lesion of the Omentum; A New Pathological Entity

Introduction/Objective

Elastotic lesions are rare benign mass-forming entity. Although, few reports of mucosal and submucosal elastotic lesions have been previously described, localization of these lesions in the omentum is not previously described in the literature.

Methods/Case Report

We report a case of 60-year-old man with medical history of obesity, hypertension, diabetes mellitus, and a remote abdominal surgery in 1980s who presented to the emergency room complaining of abrupt severe constant epigastric pain that started few hours before. The pain was not relieved by antiacid or analgesic medications. CT of the abdomen showed multiple distended fluid-filled loops of small bowel in mid abdomen with infiltrative changes of mesentery. A diagnosis of small bowel obstruction was made, and patient proceed to have an exploratory laparotomy. During the procedure, extensive adhesions between small bowel and omentum and small bowel obstruction due to a phytobezoar were noted for which he underwent lysis of adhesion, excision of thickened omentum, and enterotomy for removal of significant food bezoar. Grossly, the omentum has multiple chalky tan-gray masses ranging between 1.2 and 1.0 cm in greatest dimension surrounded by indurated fatty tissue. Microscopically, multiple hypocellular foci are seen that are composed almost entirely of truncated elastic fibers, with sparse delicate bands of collagen and scattered prominent thick-walled vessels. Elastic stain highlights these elastic fibers while trichrome stains the elastic fibers pale gray in contrast to the bright blue color of the collagen fibers. Mucicarmine, and Congo red are negative. Patient tolerated the procedure well however, postoperatively he had local wound infection leading to prolonged skin dehiscence.

Results (if a Case Study enter NA)

NA.

Conclusion

Elastotic mass-forming lesions in the omentum is a new entity that has not been described before in this location that can clinically manifest with signs and symptoms of bowel obstruction. We suggested the name of elastomatosis omentum.