Benign Lipoma Research Articles

Dermal Spindle Cell Adenolipoma

Dermal Spindle Cell Adenolipoma

Liposarcoma miRNA signatures identified from genome-wide miRNA expression profiling.

To identify the miRNA expression profile of liposarcoma (LPS) that could facilitate detection of LPS, and provide the basis for further investigation of molecular-targeted therapeutic drugs. A real-time quantitative PCR assay was performed to analyze the expression of 1888 miRNAs from 25 LPS tumor tissue samples, 16 samples of adipose tissue adjacent to the tumors and 18 normal adipose tissue samples from patients with LPS. Ten dysregulated miRNAs were identified that effectively distinguished LPS tissue from adipose tissue and benign lipoma tissue, and LPS tumor tissues from normal adipose tissues in LPS patients. Furthermore, the expression profiles of miRNAs could also classify the subtype of LPS. The identified miRNAs appear to be novel biomarkers for the detection of LPS, and may contribute to an understanding of the mechanisms of LPS tumorigenesis and its development, and further elucidate the characteristics of LPS subtypes.

Synergistic Effects of Targeted PI3K Signaling Inhibition and Chemotherapy in Liposarcoma

While liposarcoma is the second most common soft tissue malignant tumor, the molecular pathogenesis in this malignancy is poorly understood. Our goal was therefore to expand the understanding of molecular mechanisms that drive liposarcoma and identify therapeutically-susceptible genetic alterations. We studied a cohort of high-grade liposarcomas and benign lipomas across multiple disease sites, as well as two liposarcoma cell lines, using multiplexed mutational analysis. Nucleic acids extracted from diagnostic patient tissue were simultaneously interrogated for 150 common mutations across 15 essential cancer genes using a clinically-validated platform for cancer genotyping. Western blot analysis was implemented to detect activation of downstream pathways. Liposarcoma cell lines were used to determine the effects of PI3K targeted drug treatment with or without chemotherapy. We identified mutations in the PIK3CA gene in 4 of 18 human liposarcoma patients (22%). No PIK3CA mutations were identified in benign lipomas. Western blot analysis confirmed downstream activation of AKT in both PIK3CA mutant and non-mutant liposarcoma samples. PI-103, a dual PI3K/mTOR inhibitor, effectively inhibited the activation of the PI3K/AKT in liposarcoma cell lines and induced apoptosis. Importantly, combination with PI-103 treatment strongly synergized the growth-inhibitory effects of the chemotherapy drugs doxorubicin and cisplatin in liposarcoma cells. Taken together, these findings suggest that activation of the PI3K/AKT pathway is an important cancer mechanism in liposarcoma. Targeting the PI3K/AKT/pathway with small molecule inhibitors in combination with chemotherapy could be exploited as a novel strategy in the treatment of liposarcoma.

MicroRNA expression profiles distinguish liposarcoma subtypes and implicate miR-145 and miR-451 as tumor suppressors

Liposarcomas are rare, heterogeneous and malignant tumors that can be divided into four histological subtypes with different characteristics and clinical behavior. Treatment consists of surgery in combination with systemic chemotherapy, but nevertheless mortality rates are high. More insight into the biology of liposarcoma tumorigenesis is needed to devise novel therapeutic approaches. MicroRNAs (miRNAs) have been associated with carcinogenesis in many tumors and may function as tumor suppressor or oncogene. In this study we examined miRNA expression in an initial series of 57 human liposarcomas (including all subtypes), lipomas and normal fat by miRNA microarrays. Supervised hierarchical clustering of the most differentially expressed miRNAs (p < 0.0002) distinguished most liposarcoma subtypes and control tissues. The distinction between well differentiated liposarcomas and benign lipomas was blurred, suggesting these tumor types may represent a biological continuum. MiRNA signatures of liposarcoma subtypes were established and validated in an independent series of 58 liposarcomas and control tissues. The expression of the miR-143/145 and miR-144/451 cluster members was clearly reduced in liposarcomas compared to normal fat. Overexpression of miR-145 and miR-451 in liposarcoma cell lines decreased cellular proliferation rate, impaired cell cycle progression and induced apoptosis. In conclusion, we show that miRNA expression profiling can be used to discriminate liposarcoma subtypes, which can possibly aid in objective diagnostic decision making. In addition, our data indicate that miR-145 and miR-451 act as tumor suppressors in adipose tissue and show that re-expression of these miRNAs could be a promising therapeutic strategy for liposarcomas.

Breast lumps: A 21-year single-center clinical and histological analysis

Objective:To review the presentation and histological diagnosis of breast lumps of patients seen in Trans Ekulu Hospital Enugu Southeastern Nigeria from 1993 to 2013 in a period of 21 years.Materials and Methods:This is a retrospective study covering a period of 21 years. Case notes of patients containing clinical information and their histology reports were studied.Results:Only 38% of the patients came within 3 months of finding lumps in their breast. One hundred and thirty-seven patients (83%) had benign disease, i.e., fibroadenoma, mammary dysplasia, cysts, adenomas, tuberculosis, phyllodes tumor, mastitis, and lipoma. Only 16.9% i.e., 28 patients had breast cancer, out of which two females were in their 20s, and three were males.Conclusions:Benign breast diseases, i.e., fibroadenoma, fibroadenosis, cysts, adenomas, tuberculosis, phyllodes, mastitis, and lipoma are the commoner breast diseases in our locality.

腸重積で発症した結腸脂肪腫の１例

An 84-year-old man, who had been found to have a submucosal tumor in the ascending colon two years before, was admitted to our hospital for right lower quadrant abdominal pain and melena. An abdominal computed tomography (CT) scan showed intussusception in the ascending colon, resulting from a fat-density tumor. The intussusception was located by colonoscopy. Since the colonic tumor was enlarged in comparison with two years ago and had an ulcer at the top of the tumor, there was the possibility of malignancy and recurrence of intussusception. He underwent a laparoscopy-assisted right colectomy with lymph node dissection. Pathologically, the tumor of the ascending colon was a benign lipoma.

DDIT3 Expression in Liposarcoma Development.

Liposarcomas are mesenchymal tumors containing variable numbers of lipoblasts or adipocytes. The most common entities, well differentiated/dedifferentiated liposarcoma (WDLS/DDLS) and myxoid/round cell liposarcoma (MLS/RCLS), are both characterized by genetic rearrangements that affect the expression of the transcription factor DDIT3. DDIT3 induces liposarcoma morphology when ectopically expressed in a human fibrosarcoma. The role of DDIT3 in lipomatous tumors is, however, unclear. We have analyzed the expression of DDIT3 in 37 cases of liposarcoma (WDLS/DDLS n = 10, MLS/RCLS n = 16, and pleomorphic liposarcomas (PLS) n = 11) and 11 cases of common benign lipomas. Major cell subpopulations of WDLS/DDLS and MLS/RCLS tumors were found to express DDIT3 or the derived fusion protein, whereas PLS cases showed only a few positive cells. The lipomas contained large subpopulations expressing DDIT3. No correlation between numbers of DDIT3 expressing cells and numbers of lipoblasts/adipocytes was found. In vitro adipogenic treatment of two DDIT3 expressing cell lines induced lipid accumulation in small subpopulations only. Our results suggest a dual, promoting and limiting, role for DDIT3 in the formation of lipoblasts and liposarcoma morphology.

Subacromial impingement syndrome caused by a voluminous subdeltoid lipoma.

Subacromial impingement syndrome is a clinical diagnosis encompassing a spectrum of possible etiologies, including subacromial bursitis, rotator cuff tendinopathy, and partial- to full-thickness rotator cuff tears. This report presents an unusual case of subdeltoid lipoma causing extrinsic compression and subacromial impingement syndrome. The patient, a 60-year-old man, presented to our institution with a few years' history of nontraumatic, posteriorly localized throbbing pain in his right shoulder. Despite a well-followed 6-months physiotherapy program, the patient was still suffering from his right shoulder. The MRI scan revealed a well-circumscribed 6 cm × 2 cm × 5 cm homogenous lesion compatible with a subdeltoid intermuscular lipoma. The mass was excised en bloc, and subsequent histopathologic examination confirmed a benign lipoma. At 6-months follow-up, the patient was asymptomatic with a complete return to his activities. Based on this case and a review of the literature, a subacromial lipoma has to be included in the differential diagnosis of a subacromial impingement syndrome refractory to nonoperative treatment. Complementary imaging modalities are required only after a failed conservative management to assess the exact etiology and successfully direct the surgical treatment.

Intrathoracic chest wall lipoma: mimicking a soft tissue neoplasm on a chest radiograph

A 44-year-old eastern European woman presented to the tuberculosis (TB) service after she had a pre-employment TB screening chest radiograph. The frontal anteroposterior (AP) chest radiograph demonstrated a soft-tissue opacity projected over the lateral aspect of the right hemithorax, with poorly defined lateral margins (Fig 1a). The ancillary lateral chest radiograph demonstrated a welldefined soft-tissue lesion projecting posterior to the right breast, across the anterior thoracic wall into the right lung field (Fig 1b). The features were consistent with a soft-tissue extrapulmonary chest wall abnormality. The patient went on to have a computed tomography (CT) scan of the chest, which demonstrated a wellcircumscribed, uniformly homogeneous, low-attenuation lesion measuring 3 cm, which projected across the pleural margin into the right lung field (Fig 1c). It had a mean Hounsfield unit (HU) value of −105 HU and was radiologically consistent with a benign intrathoracic lipoma. There was no mediastinal or hilar lymphadenopathy and the abdominal viscera were normal. Lipomas are benign neoplastic mesenchymal tumours arising from adipose tissue. They are well defined and encapsulated. Intrathoracic lipomas are extremely rare, and usually located centrally in the anterior mediastinum, although they can also be found peripherally. They account for 1.6–2.3% of all mediastinal tumours, 0.1% of all lung tumours and 13% of all benign lung tumours. 1 Most are

Hepatobiliary and Pancreatic: Large pancreatic liposarcoma

A young man, aged 24, was investigated because of progressive abdominal distension. On examination, he had a large mass in the mid-abdomen. A contrast-enhanced computed tomography (CT) scan revealed a mass, 25 x 17 x 11 cm, in the mid-abdomen as shown on the axial and coronal scans in Figure 1. The mass had a heterogeneous appearance but many areas of the mass were of low-density consistent with fat. The preoperative diagnosis was that of a retroperitoneal liposarcoma. Laparotomy revealed a relatively firm tumor with a smooth surface (Figure 2). The mass appeared to arise from the body of the pancreas with sparing of the tail of the pancreas (arrowheads). A resection of the body of the pancreas was performed with a pancreaticogastrostomy for the distal pancreatic remnant. At histology, the diagnosis was that of a myxoid pancreatic liposarcoma with surgical margins that were free of tumor. After 44 months, a second operation was performed to remove a local recurrence, 4 x 3 cm in size. He is currently asymptomatic after 3 further months of follow-up. Liposarcomas are malignant neoplasms of adipose tissue. Histologically, the most common types are the well-differentiated liposarcoma, the myxoid liposarcoma and the dedifferentiated liposarcoma. These tumors largely develop in middle-aged or older individuals. Common sites for the dedifferentiated liposarcoma include the retroperitoneum and the spermatic cord. In contrast, well-differentiated and myxoid liposarcomas usually occur in subcutaneous and intramuscular sites and are uncommon in the retroperitoneum. Retroperitoneal liposarcomas, in particular, are often relatively large at the time of diagnosis and only rarely arise from the pancreas. The behavior of liposarcomas is strongly influenced by the histology such that the dedifferentiated liposarcoma is more likely to recur locally and metastasize. The most important factor influencing prognosis is the adequacy of surgical resection at the time of primary presentation. The CT scan illustrated above is typical of a liposarcoma with low density areas consistent with fat as well as thick septae of soft tissue. Dedifferentiated neoplasms have less fat and can have a similar appearance to other sarcomas. The differential diagnosis on imaging may also need to include benign lipoma, angiomyolipoma and malignant fibrous histiocytoma.

Beyond the depths: deep-seated lipoma of the upper limb

Background Deep-seated lipomas are mature fat tissues which may occur in intermuscular, intramuscular, or submuscular locations. Unlike benign subcutaneous lipoma, which usually only grow on skin surface, deep-seated lipoma generally grow slowly and may sometimes infiltrate deeply and wrap around nerves.

Surgical treatment of an endobronchial lipoma obstructing the right upper bronchus: Imaging features with pathological correlation

Endobronchial lipomas are rare benign unusual tumors of the respiratory tract. We describe a 65-year-old Chinese man with a history of cough due to an endobronchial tumor. The endobronchial biopsy was not excisional and was unable to evaluate the whole tumor. Then the mass was successfully resected via a right lateral thoracotomy. The histopathological diagnosis confirmed a benign lipoma arising from the membranous trachea. His CT features and fiberoptic bronchoscopic findings are shown along with the pathological results. In describing the management of this case, we stress that the clinical treatment of such tumors should be individualized according to the characteristics of each patient and mass.

Lipoma in Penis : A Rare Case Report

In this article we report one case of lipoma of the penis in a twenty three years old young male. This site of lipoma is rare. A case of a young male patient who consulted for removal of a penile lump is presented. The small, regular, wellcircumscribed pedunculated tumor localized on the ventral aspect of the penis was excised. The histopathological analysis showed a benign lipoma. A review of the literature showed lipoma of the penis to be very uncommon. For this reason, we were prompted to report this case.DOI: http://dx.doi.org/10.3329/bdjps.v3i1.15003 Bangladesh Journal of Plastic Surgery 2012, 3(1): 24-25

Giant Lipoma of the Breast

Lipomas are benign mesenchymal tumors that develop in areas of abundant adipose tissue. Due to the fatty composition of the breast, difficulties in diagnosis, treatment, and reconstruction are often encountered. We report a case of a 55-year-old female with a giant tumor of the right breast that comprised most of its mass, causing breast asymmetry. A thorough preoperative evaluation, followed by an uneventful difficult surgical resection and reconstruction, resulted in diagnosis of a benign lipoma. The case prompted this report because of its challenging size, location, diagnosis, and reconstructive solution.

An unusual location of osteolipoma: a case report

Lipomas are the most common benign tumors of soft tissue in adults [1]. They may be located in either deep or surface tissues. Deep tissue-located lipomas are classified as intramuscular, intermuscular, parosteal, and interosseous lipomas [1]. It is common to encounter intraosseous lipomas originating from bony tissues, whereas it is very rare to encounter adipocytic cells with osteoid and/or chondroid tissues independent of bony tissues [2]. Osteoid lipomas (benign osteoid lipoma, osteolipoma, degenerative osteolipoma) are lipomas containing mature osteoid tissues [3, 4]. Osteoid lipomas are reported to be less than 1 % in the literature [2]. Osteolipomas, which found independent of bony tissue, are rare kind of tumors [5]. In our study, we intend to report a rare case of osteolipoma with a rare location independent of bony tissue and to emphasize that this lesion should be included in differential diagnosis of lipomatous lesions present in extremities.

Renal Lipoma: a case report

Abstract Renal lipoma is a very rare tumor that has only been described in about twenty cases in adults and in a single case in a child aged 2 years. This paper presents a renal lipoma in 63 year old female patient. The tumor size of 7.5×4.5 cm was located in her right kidney, clearly delineated from the surrounding kidney tissue, and histology was completely built of mature adipose tissue. This paper describes the case of a rare benign lipoma which histogenesis is yet not clearly understood.

Giant lipoma of the third finger of the hand

We report a case of a 50-year old female presenting with a giant tumor on the volar aspect of the third finger of the left hand, a thorough clinical and paraclinical evaluation followed by surgical resection resulted in a benign lipoma with an uneventful postoperative course. We present this case due to its rare location and repercussion in the decision making process when other more common similar pathologies with varying prognosis are conceived.

Diagnostic utility of aP2/FABP4 expression in soft tissue tumours

Adipocyte P2 (aP2), also known as fatty acid-binding protein 4 (FABP4), is a fatty acid-binding protein found in the cytoplasm of cells of adipocyte differentiation. In this study, we examined a large number of soft tissue tumours with a commercial polyclonal anti-aP2/FABP4 antibody and a newly developed mouse monoclonal antibody raised against this protein to determine the diagnostic utility of aP2/FABP4 as a marker of tumours of adipose differentiation. A mouse monoclonal antibody, clone 175d, was raised against a mixture of synthetic peptides corresponding to the amino acid sequence of residues 10-28 and 121-132 of the human aP2/FABP4 protein. Antigen expression with polyclonal and monoclonal antibodies was immunohistochemically determined in paraffin sections of normal adipose tissue and a wide range of benign and malignant primary soft tissue tumours (n = 200). aP2/FABP4 was expressed around the cytoplasmic lipid vacuole in white and brown fat cells in benign lipomas and hibernomas. Immature fat cells and lipoblasts in spindle cell/pleomorphic lipoma, atypical lipomatous tumour/well-differentiated liposarcoma, myxoid/round cell liposarcoma and pleomorphic liposarcoma also reacted strongly for aP2/FABP4. No specific staining was seen in non-adipose benign and malignant mesenchymal and non-mesenchymal tumours. aP2/FABP4 is expressed by mature and immature fat cells and is a marker of tumours of adipose differentiation. Immunophenotypic aP2/FABP4 expression is useful in identifying lipoblasts, and immunohistochemistry with polyclonal/monoclonal anti-aP2/FABP4 antibodies should be useful in distinguishing liposarcoma from other malignancies, particularly round cell, myxoid and pleomorphic soft tissue sarcomas.

Large benign submucosal lipoma presented with descending colonic intussusception in an adult

Patient: Female, 34Final Diagnosis: Lipoma of the large intestineSymptoms: Abdominal pain • bloating • blood in stool • constipation • lose of appetite • nauseaMedication: —Clinical Procedure: —Specialty: SurgeryObjective:Rare diseaseBackground:Lipoma of the large intestine is rare, account for only 5% of all gastrointestinal tumors. Lipomas are usually asymptomatic but rarely may cause bleeding, obstruction and intussusception. We present a case of a giant colonic lipoma causing descending-colonic intussusception.Case Report:34 yo F presented with the intermittent left lower quadrant abdominal pain for 3 weeks. The pain initially was associated with bloating and constipation and for the last several days frank blood in stool, nausea and decreased appetite. CT scan of the abdomen revealed descending colonic obstruction by a 5.3 cm colonic lipomatous mass with resultant intussusception. Patient initially underwent colonoscopy that revealed polypoid lesion at 3–40 similar to lipoma with intussusception that was reduced. Patient subsequently underwent laparoscopic segmental left colectomy for the descending colonic intussusception due to large colonic lipomatous mass. Pathology confirmed the histology of lipoma.Conclusions:Adult bowel intussusception is a rare but challenging condition to diagnose in a timely manner. Preoperative diagnosis is usually missed or delayed because of nonspecific and often subacute symptoms. Lipoma is a rare cause of the intussusception. A high index of suspicion and appropriate investigations (abdominal ultrasound, CT scan and colonoscopy) can result in prompt diagnosis. Lipoma of the large intestine is very rare. Submucosal lipomas are usually asymptomatic but may cause bleeding, obstruction, intussusception, or abdominal pain. Accurate preoperative diagnosis is difficult and lipoma is often mistaken for adenomatous polyp or carcinoma. Treatment usually requires formal resection of the involved bowel segment due to high suspicion for malignancy and subsequent complications due to obstruction.

Large Cecal Lipoma With Overlying Ulceration Simulating Malignancy: A Case Report and Review of Relevant Literature

Gastrointestinal lipomas are rare, usually single, slow growing benign non-epithelial tumors. Most colonic lipomas are asymptomatic and are usually detected incidentally during colonoscopy, surgery or autopsy. In a small percentage of cases, especially when their diameter is greater than 2 cm, they can cause symptoms. The common presenting symptoms include constipation, diarrhea, colicky abdominal pain, change in bowel habit, bowel obstruction, lower gastrointestinal bleeding, intussusception or prolapse. Imaging techniques, including CT and MRI are regularly used. However, preoperative diagnosis of colonic lipoma is often difficult with the majority of the lesions diagnosed by laparotomy and definitive diagnosis is made based on histopathological examination. Colonoscopy permits direct visualization of the submucosal lipoma. Endoscopy can usually distinguish lipomas from other tumors. Lipomas are seen as smooth, rounded yellowish polyps with a thick stalk or broad-based attachment. Typical colonoscopy features are the “tent sign” (elevation of the mucosa over lipoma with biopsy forceps), “cushion sign” or “pillow sign” (pressing forceps against the lesion results in depression or pillowing of the mass) and the “naked fat sign” (extrusion of yellowish fat at the biopsy site. The mucosa overlying a colonic lipoma is intact. In rare cases, colonoscopy may reveal large-sized flat-shaped mass with ulceration that may lead to an impression of malignancy. Colonoscopic biopsy is often performed to determine the exact nature of the tumor. However colonic lipomas may result in mucosal inflammation of adjacent tissue giving the false impression of “nonspecific colitis” . This is particularly true in cases of inadequate tissue sample. Recently, virtual colonoscopy has been performed to detect colonic lipomas. Lipomas less than 2 cm in diameter can be removed endoscopically whereas larger lesions should be removed surgically either by open or laparoscopic methods. Colonoscopic resection of large colonic lipomas remains a controversial subject till date. Although a wide range of operative techniques including colostomy and excision, hemicolectomy or subtotal colectomy are employed, segmental resection is usually the procedure of choice. We describe a patient with persistent abdominal pain who underwent open right hemicolectomy for the presumptive endoscopic diagnosis of cecal adenocarcinoma and discuss diagnostic modalities and treatment options. Histological examination confirmed that the resected specimen was a giant benign cecal lipoma. doi: http://dx.doi.org/10.4021/jcs34w