Primary omental leiomyosarcoma masquerading as hemorrhagic ascites

Idiopathic omental hemorrhage: a case report and review of the literature

BACKGROUND

A spontaneous rupture of an omental vessel can cause severe intraabdominal hemorrhage. We present a case of idiopathic omental hemorrhage caused by a vascular malformation. The literature is systematically reviewed.

CASE PRESENTATION

A 65-year-old Iranian man was admitted to the emergency department for 10 days with abdominal pain. His medical history was not significant. Fever, vomiting, nausea, or anorexia were not reported. However, he was suffering from diaphoresis and malaise at the time. He did not smoke or drink alcohol. During physical examination, blood pressure was 82/60 mmHg with a temperature of 36.6 °C; heart rate was 96 beats/minute and respiratory rate was 18 breaths per/minute. An abdominal examination revealed mild tenderness in the periumblical. The focused assessment with sonography in trauma examination yielded positive results. The complete blood count showed 14 × 103/mcL of white blood cells and 185 × 103/mcL of platelets. The hemoglobin value was 6.7 g/L at admission. To stabilize the patient's condition, a unit of packed cell was administered. A double contrast enhancement abdominal computer tomography was performed, which revealed a massive hemoperitoneum. Subsequently, an exploratory laparoscopy was performed to search for the responsible pathology. But it was not successful. The surgical plan was changed to laparotomy. The hemorrhage source was not found during laparotomy. Observation revealed a massive hemoperitoneum originating in the omental vessels. A portion of the omentum located on the greater omentum at the greater curve was removed. Based on the pathological examination of the extracted tissue, vascular malformations were identified. The patient recovered uneventfully and was discharged from the hospital 7 days after surgery. Previous reports assessing idiopathic omental bleeding were systematically reviewed. A total of 14 hits were identified in PubMed and Scopus from 2015 to November 2022 for idiopathic omental bleeding.

CONCLUSION

Presence of positive focused assessment with sonography in trauma, abdominal pain, imaging evidence of fluid accumulation, and a reduction in hemoglobin levels collectively indicate the likelihood of arteriovenous malformation occurrence. The treatment options include surgical intervention and transcatheter arterial embolization. Surgical intervention is recommended for subjects with hemodynamic instability, persistent hypotension and those whose diagnosis is unconfirmed.

Primary Omental Lipoma in a Child: A Case Report and Literature Review

BACKGROUND

Lipoma is a common benign tumor derived from adipose tissue, with an incidence of nearly 10%. It is the most common mesenchymal tumor throughout the body. However, the pathogenesis of lipoma is not clear yet, and the increased incidence is attributable to obesity, elevated serum cholesterol, diabetes, trauma, radiation, familial predisposition, and chromosome. Primary omental tumor is a rare lipoma occurring in the greater omentum, most of which is reported in the form of clinical case reports. Nevertheless, primary omental tumor is even rarer in children. To date, there have been few reports of clinical cases.

CASE PRESENTATION

We report a rare case of primary omental lipoma in a 6-year-old boy. After an accidental fall, a CT scan found that he had a tumor in the left upper abdomen. He had no history of abdominal pain, abdominal mass, vomiting, etc. The boy was admitted to the hospital within 3 days, and was diagnosed with an intra-abdominal tumor. After admission, abdominal ultrasound and enhanced CT showed a 71 ×40 ×60 mm mass in the left middle abdomen, which was considered a lipoma. There was no abnormality in tumor markers. Through laparoscopic surgery, intraoperative exploration revealed that the tumor was located in the left mid-upper abdomen, and was yellow, solid, soft, and isolated. The intraoperative diagnosis was an omental lipoma. We used an ultrasonic knife to resect the omentum close to the base of the tumor. The tumor was completely resected, put in a retrieval bag and sealed. Finally, the left and right sides of the umbilical incision were extended to take out the tumor tissue. The child received liquid food 6 h after the operation and was discharged 3 days later. The postoperative pathological diagnosis was an omental lipoma. He was seen at follow-up 3 months after discharge and had no complaints, an abnominal ultrasound showed no tumor recurrence.

CONCLUSION

Primary omental lipoma in children is a rare benign tumor of the omentum. Its etiology and pathology are not clear. US, CT, and MRI can facilitate clinical diagnosis and preoperative evaluation. Laparoscopic surgery is an effective treatment, and the prognosis of children is favorable. This case is beneficial to improve the clinical knowledge of pediatric surgeons about this rare disease.

Spontaneous omental bleeding: a case report and literature review

BACKGROUND

Spontaneous rupture of omental vessels is an infrequent medical condition possibly causing severe intra-abdominal hemorrhage. Omental bleeding results from trauma associated injury and irritation, neoplasia, arterial aneurysm rupture, and anticoagulant treatment. Idiopathic omental bleeding rarely causes acute abdominal bleeding which has been reported to occur in previous studies. Here we reported a case with idiopathic omental hemorrhage due to vascular malformation. A systematic review of literature is provided.

CASE PRESENTATION

A 58-year-old Han Chinese man arrived at the emergency department with left upper quadrant abdominal pain for 1 day. He had no significant previous medical history. There was no history of fever, vomiting, nausea, or anorexia. He was a non-smoker and did not consume alcohol. On physical examination, blood pressure was 118/72 mmHg, for a temperature of 37.7 °C; heart and respiratory rates of 130 per/min and 20 per/min were obtained, respectively. Abdomen assessment showed only mild tenderness in the left upper quadrant. Complete blood count (CBC) showed white cell and platelet counts of 16.69 × 10³/L and 196 × 10³/L, respectively. The haemoglobin value was 13.5 g/L at admission. Abdominal Computer Tomography (CT) was performed that showed peritoneal fluid appeared around the liver. Fresh blood was confirmed in the abdominocentesis. A hemoperitoneum was confirmed by abdominal enhanced CT, which presented a structural disorder in the left upper abdomen. The subject immediately underwent exploratory laparotomy. A massive hemoperitoneum originating from omental vessels was observed. The omental were partially removed. There was no evidence of malignancy or aneurysm upon palpation. Pathological assessment of the extracted tissue pointed to vascular malformation. The patient subsequently had an uneventful recovery; hospital discharge occurred at 7 days post-operation. Previous reports assessing idiopathic omental bleeding were systematically reviewed, summarizing published cases. A total of 12 hits were found in PubMed for idiopathic omental bleeding.

CONCLUSION

Idiopathic omental bleeding is a rare condition that requires emergency treatment. Treatment strategies include surgical intervention and transcatheter arterial embolization (TAE). The surgical option is suitable in subjects with persistent hypotension and those with unconfirmed diagnosis.

A rare diagnosis of abdominal pain presentation in the emergency department: Idiopathic omental bleeding: A case report

RATIONALE

Idiopathic omental bleeding is a rare cause of acute abdomen, with only a few reported cases. It usually presents with abdominal pain and may be life-threatening. As it rarely occurs, it may not be considered initially during patient presentation.

PATIENT CONCERNS

A 35-year-old male came to our emergency department with abdominal pain present for around 5 to 6 hours. The patient complained of left upper quadrant abdominal pain after eating breakfast. The only associated symptom was 3 episodes of vomiting up food. Physical examination revealed mild left upper quadrant abdominal tenderness without muscle guarding or rebounding pain. Blood examination showed leukocytosis with neutrophil predominance and C reactive protein elevation. The pain was persistent and relief was not obtained by medication.

DIAGNOSES

Computed tomography showed a large lobular-contour homogenous slightly hyperdense lesion without enhancement along the greater curvature of the stomach in the lesser sac. A surgeon was consulted and laparotomy was suggested. Hematoma was found at Morrison pouch, subsplenic fossa, and lesser sac under operation.

INTERVENTION

Laparotomy and ligation for hemostasis.

OUTCOMES

The patient was discharged with stable condition after 7 days of hospitalization.

LESSONS

This diagnosis should be considered in patients presenting with epigastric pain and vomiting after eating while in the emergency department because this disease might be life-threatening. This case highlights 2 important learning points. First, idiopathic omental bleeding could occur after eating in patients without underlying disease or trauma history, and this disease should be taken into consideration when acute abdomen occurs. Second, emergent laparotomy is indicated if the cause of acute abdomen is not clear.

Primary leiomyosarcoma of the greater omentum: a case report

INTRODUCTION

Greater omentum leiomyosarcomas are rare tumors with only a few cases reported in literature.

PRESENTATION OF CASE

We report the case of a 68-year-old man who consulted complaining of diffuse abdominal pain without a palpable mass at physical examination. Imaging studies revealed a solid-cystic lesion in the right lower quadrant. Surgical resection was performed and the tumor was diagnosed as a leiomyoscarcoma by histological and immunohistochemical examinations.

DISCUSSION

Surgical resection of all lesions seems to be a reasonable therapeutic approach if resection is feasible. Chemotherapy may be used in selected cases.

CONCLUSION

More cases are needed to define the best treatment approach of this disease.

Idiopathic omental hemorrhage: A case report and review of the literature

INTRODUCTION

Omental hemorrhage results from rupture of the omental vessels. There are many causes of omental hemorrhage including trauma, aneurysm, and vasculitis. Idiopathic omental hemorrhage is a rare cause of an acute abdomen, which is potentially life-threatening. We report a patient with idiopathic omental hemorrhage, which may have been caused by overeating.

CASE PRESENTATION

A 29-year-old man without a history of trauma, bleeding disorders, or other significant medical history, presented with left upper quadrant pain, which began after overeating the previous evening. The pain worsened and he presented to the emergency department. On physical examination, his BP was 111/69mmHg and pulse 71 and he reported tenderness and involuntary guarding in the left upper quadrant on palpation. Contrast enhanced computed tomography scan revealed intraperitoneal fluid collection with intra-omental extravasation. Significant intraperitoneal hemorrhage was suspected and emergency laparotomy was performed. On exploring the abdominal cavity, a hematoma was found in the greater omentum, adjacent to the right gastroepiploic artery. No active bleeding was seen, and partial omentectomy was performed. There were no obvious lesions suggestive of malignancy or aneurysm, supporting the diagnosis of idiopathic omental hemorrhage. On postoperative day six, the patient developed a wound dehiscence, which was surgically closed. The subsequent postoperative course was uneventful and he was discharged on fifth day after the second operation.

CONCLUSION

Idiopathic omental hemorrhage is a rare cause of an acute abdomen, which may develop after eating. Omentectomy is preferred to ligation or transcatheter arterial embolization to rule out an underlying malignancy or aneurysm.

Primary leiomyosarcoma of the omentum presenting as an ovarian carcinoma, case report and review of the literature

Primary omental leiomyosarcoma is a rare tumor. We report a case of successfully resected omental leiomyosarcoma whose presentation mimicked ovarian carcinoma. Symptoms of abdominal distension and discomfort that lasted 8 months followed by pain lead to a diagnosis of a large mass in the abdomen. Physical examination revealed a large, over 20 cm tumor, suspected to be of ovarian origin. A small amount of ascites was found on Computerized Tomography (CT) and ultrasound (US) scans. Total abdominal hysterectomy with bilateral salpingo-oophorectomy, omentectomy and tumor debulking procedure was planned. Laparotomy revealed normal uterus ovaries and tubes with a leiomyosarcoma of the omentum which was completely resected successfully. Only 26 cases of primary leiomyosarcoma of the omentum were previously described in the literature. A review of the literature is also presented.

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Primary leiomyosarcoma of the omentum can mimic the presentation of an ovarian carcinoma.

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The diagnosis is based mostly on the appearance on Computerized Tomography scan and angiography.

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Complete surgical resection of this tumor can lead to long term survival.

Spontaneous rupture of the omental artery treated by transcatheter arterial embolization

Intra-abdominal hemorrhage caused by omental artery rupture is a rare condition. There are few reports on the treatment of omental artery rupture with only transcatheter arterial embolization (TAE). A 27-year-old man presented to our emergency room with upper abdominal pain that suddenly occurred during sleep. Abdominal computed tomography (CT) revealed fluid collection in the peritoneal cavity and a left subphrenic hematoma with extravasation. Celiac angiography revealed extravasation from the omental artery, which arose from the proximal left gastroepiploic artery. A microcatheter was advanced into the left gastroepiploic artery and around the culprit artery bifurcation, which was embolized by inserting coils. The postoperative course was uneventful without worsening of anemia or abdominal symptoms. The patient was discharged after the absence of extravasation was confirmed by contrast-enhanced CT. Although surgical therapy has often been performed for omental bleeding, TAE, which is less invasive and has the advantage of simultaneous diagnosis and treatment, should be attempted as the first-choice therapy.

Laparoscopic examination and resection for giant lipoma of the omentum: a case report and review of related literature

We report herein the case of a giant lipoma of the greater omentum that was treated by laparoscopic surgery. A 71-year-old male patient was admitted with a diagnosis of sigmoid colon cancer. During preoperative examination, a gallbladder stone and an intra-abdominal giant lipoma were accidentally diagnosed. Laparoscopic examination revealed a smooth-surfaced, giant yellow tumor at the lower border of the greater omentum that was unattached to the surrounding organs. After laparoscopic resection of the tumor and cholecystectomy, a 10-cm midline incision was made in the lower abdomen to remove the tumor and the gallbladder. We then performed a sigmoidectomy for sigmoid colon cancer through the same laparotomy. The resected tumor measured 29 x 19 x 3 cm and weighed 1250 g, and a histopathologic examination revealed a benign lipoma. Laparoscopic examination and resection of a giant lipoma of the omentum are particularly useful.

Malignant mesothelioma of the greater omentum mimicking omental infarction: A case report

Mesothelioma develops most commonly in the pleura, and less frequently in the peritoneum. Usually, it manifests as diffuse peritoneal thickening and multiple nodules, and rarely as a solitary mass. We report a rare case of primary malignant mesothelioma of the greater omentum, which mimicked omental infarct. A 54-year-old Korean man was admitted because of severe abdominal pain of sudden onset. A tender mass with indistinct margins was palpated in the upper abdomen. Abdominal ultrasound and computed tomography showed an ill-defined mass in the greater omentum and little ascites in the peri-hepatic space, and neutrophil-dominant exudates were documented on paracentesis. Intravenous antibiotics and analgesics were given for omental infarction with superimposed infection, which resulted in symptomatic improvement. The imaging studies after a week revealed a growing mass and ascites. Laparoscopic surgery was performed and an 8 cm × 3.3 cm greater omental mass was found, with multiple small nodules on the peritoneum, diaphragm, and pelvic cavity wall. Histological examination showed proliferating malignant epithelioid cells that stained strongly for calretinin, which was compatible with malignant mesothelioma. We recommend that primary omental mesothelioma should be included in the differential diagnosis of patients with omental infarction, despite its rarity.

A case of primary leiomyosarcoma of the lesser omentum

Leiomyosarcoma is a rare tumor that originates in the smooth muscle, usually in the gastrointestinal tract, the retroperitoneum and the genitourinary tract. The omentum has been rarely reported as a primary site of occurrence with leiomyosarcoma. A 72 year-old woman, with palpable mass on the left upper quadrant of abdomen and weight loss, was admitted to St. Paul's Hospital. Abdominal CT scan showed a 12 x 8 x 8 cm-sized cystic mass in the left upper quadrant of the abdomen. Endoscopic ultrasonography showed a large cystic mass between the stomach and the liver, which was 1.6 cm length in wall thickness. Laparotomy and resection of the mass was performed. A 12 x 8 x 8 cm-sized mass, originated from the lesser omentum, was discovered near the lesser curvature of the stomach. Microscopic examination revealed spindle-shaped cells with 7-8 mitoses per high power field. She was diagnosed as primary leiomyosarcoma originated from the lesser omentum.

A case of leiomyoblastoma (epithelioid leiomyosarcoma) of the greater omentum

A 59-year-old male complained of a palpable abdominal mass which was revealed to be a primary omental tumor by means of abdominal ultrasonography, computed tomography, angiography and laparoscopy. Histological examinations of the surgically resected tumor further disclosed leiomyoblastoma with positive stainings of both vimentin and desmin, markers for mesenchymal cells and for muscle cells, respectively. He has been well for 2 years since resection, without any relapse or distant metastasis of the tumor. Leiomyoblastoma of the greater omentum is very rare, and is important to distinguish from extraluminal tumor of the abdomen.

Primary omental tumor with ultrastructural features of cellular schwannoma and absence of S-100 antigen reactivity

We report a primary well-delimited, large mesenchymal omental neoplasm which appeared in a 58 year old man without neurofibromatous traces. The histological and ultrastructural features were consistent with a Schwann cell origin. However, repeated immunohistochemical reactions failed to demonstrate protein S-100 antigen reactivity in the neoplastic cells, the latter only expressing vimentin. The differential diagnosis with hemangiopericytoma is proposed.