Spindle Cell Lipoma of the Shoulder: A Case Report

Spindle cell lipoma (SCL), an uncommon variant of benign lipomatous tumor, occurs predominantly in the posterior neck or the shoulders. Patients usually present a well-circumscribed and non-aggressive subcutaneous mass. Histopathologically, the mass comprises fat, CD34-positive spindle cells, and ropey collagen on a myxoid matrix. We report a case of left-shoulder SCL in a 45-year-old Saudi male nonsmoker with no known trauma. A soft tissue mass was seen on MRI near the posterior shoulder. It was a 4.5 cm x 3 cm subcutaneous rounded lump with heterogeneous signal intensity. There is no aggressive or invasive feature, and there is no significant fatty content. The mass was surgically excised with no complication. Histological examination revealed a neoplastic lesion constituted of mature adipocyte lobules and proliferation of loosely held bland spindle-shaped cells against a myxoid background. These cells exhibit neither increased mitoses nor nuclear pleomorphism. There were intervening rope collagen bundles. Lipoblasts and atypical stromal cells are also unidentified. At the periphery, a thin capsule was identified. There is no evidence of malignancy. To the best of our knowledge, this is the first reported case in Unaizah, Al Qassim. The correct diagnosis of SCL without a lipogenic component may be made by paying close attention to the clinical setting, histologic characteristics, immunohistochemical profile, and chromosomal abnormalities.

Lipoma in Parotid Gland: A Rare Case Report

Lipoma is a benign, rare, mesenchymal tumor found in the head and neck region, especially in the parotid gland. It thus requires a careful and precise examination to establish a diagnosis. A surgical procedure of the parotid gland is challenging due to the associated risk factor of facial nerve injury. We report a rare case of head and neck region lipoma between the superficial and deep lobe of the parotid gland. A 44-year-old female patient was presented with the chief complaint of a painless lump on the left front ear to the left cheek for about 1 year. There were no complaints of tooth pain before the lump appeared, and there were no lumps in other regions. A fine-needle aspiration biopsy, ultrasonography, and magnetic resonance imaging were all performed to establish the preoperative diagnosis and to plan the correct surgical approach. Lipoma was the initial clinical diagnosis, and a surgical excision with superficial parotidectomy and facialis nerve preservation was performed. Follow-up examinations were conducted to assess any facial nerve injury complications. Conclusion Lipoma rarely grows in the parotid gland. Careful diagnosis should be performed to establish a precise surgery for parotid dissection and facial nerve preservation.

Oral fibrolipoma: A rare clinicopathological entity

Fibrolipoma, a subtype of lipoma, is a painless, well-circumscribed, slow-growing, submucosal benign adipocyte tumour. It is uncommon in the oral cavity and oropharyngeal region. It accounts for 1.6% of all facial lipomas. Fibrolipomas mostly affect the buccal mucosa and buccal vestibule and cause functional and cosmetic disabilities. The diagnosis and differentiation of fibrolipoma with clinically similar lesions such as fibroma and pleomorphic adenoma are very essential for a correct treatment plan and complete follow-up. Here, we present fibrolipoma, a very rare subtype of lipoma involving the buccal mucosa of the left premolar region in a 44-year-old male patient.

Intraoral Lipoma: A Case Report

The soft tissue tumor lipoma is quite frequent. Although it is the most mesenchymal tumor of the trunk and proximal regions of the extremities, it is quite uncommon to find it on the oral mucosa, accounting for just 1% to 5% of benign oral tumors. There is no specific location that is more prone to lipoma development in the mouth. Some frequent sites are the tongue, buccal mucosa, and the mouth's floor. A Yellowish mass with no symptoms is the normal clinical appearance. In most cases, the overlaying epithelium is unharmed, and superficial blood vessels may be seen passing through and around the tumor. The differential diagnosis might also include granular cell tumors, neurofibroma, traumatic fibroma, and diseases of the salivary glands (mucocele and mixed tumor). Herein a detailed case of a 28-year-old woman with a right-sided lower-lip oral lipoma is presented in this paper.

Cerebellopontine Angle Lipoma with Contralateral Sudden Deafness: A Case Report and Review of Literature

BACKGROUND

Cerebellopontine angle lipoma is a rare tumor that composes less than 1% of all CPA tumors. There has been no recorded case of unilateral CPA/IAC lipoma with sudden contralateral deafness yet.

CASE PRESENTATION

We report a 52-year-old man diagnosed with right cerebellopontine angle lipoma and combined left total deafness. Pure-tone audiometry revealed total sensorineural deafness in his left ear and moderate sensorineural deafness in the right ear. The patient was treated with glucocorticoids, batroxobin, and other symptomatic treatments. There was no substantial improvement in hearing after 14 days' treatment.

DISCUSSION

We chose conservative treatment for him. It is advised to wear hearing aids in the right ear and to undergo regular imaging monitoring.

CONCLUSION

Treatment options for such patients should be chosen by taking into account the degree of bilateral hearing loss, the size and location of the tumor, the possibility of preserving hearing during surgery, the functional level of the patient's facial nerve, and other factors.

Fatty syringomyelia mimicking lipoma with spinal cord pilocytic astrocytoma

The reporting case is a 27 year-old woman. She was admitted with complaints of clumsy gait and dysesthesia over her upper limbs and spasticity in the legs. The investigations revealed a long segment cervical intramedullary tumor, associated with whole cord syringomyelia. The superior part of syringomyelia image intensity matched intramedullary lipoma completely. C1-C5 intramedullary tumor was resected grossly under microscopic view, and a fat-containing liquid exited the syringomyelia cavity at its superior pole. After a transient paresis just following the surgery, neurological condition was improved. The follow-up imaging showed that the fatty syringomyelia reduced in dimensions. Conclusion. According to this case and another similar case due to instability, it appears that as a rare phenomenon, syringomyelia liquid content sometimes could have fatty droplets which could mimic intramedullary lipoma with an unknown mechanism. It seems these fat droplets in syringomyelia would not change its natural history.

An Unusual Cause of Intractable Hiccups

Hiccups are a minor nuisance for most people and usually resolve within minutes. However, for some, they can persist for years and result in severe symptoms and even death. This case report describes a patient found to have a mediastinal lipoma resulting in intractable hiccups. The discussion highlights the pathophysiology, etiologies, and treatments of hiccups.

Successful endoscopic submucosal dissection of colorectal lipoma with an overlying adenoma

We report the case of a 65-year-old woman whose colonoscopy revealed a soft submucosal tumor approximately 7 cm in diameter in the ascending colon with an overlying flat lesion. The tumor was diagnosed as a lipoma with an overlying adenoma. Endoscopic submucosal dissection (ESD) was performed. Pathological examination revealed that the epithelium was a low-grade tubulovillous adenoma, while the submucosal yellow tumor was a lipoma. ESD appears to be a safe and effective treatment for colorectal lipomas overlying lipomas with colorectal adenomas.

Successful Resection of Gastric Subepithelial Lipoma Using the Bite-on-Bite Approach: Reviving Old Techniques in a Peripheral Hospital

Subepithelial lesions (SELs) are common findings in the gastrointestinal (GI) tract. They are often benign and asymptomatic but can cause symptoms in some cases. The approach to endoscopic management of these lesions depends on various factors, including associated symptoms, location, available equipment, and operator expertise. In this case report, we present a 50-year-old male with long-standing dyspepsia who was found to have a submucosal lesion in the stomach. The lesion was successfully treated using the bite-on-bite method with cold biopsy forceps. This report aims to discuss gastric subepithelial lesions and current management options, and highlight an old technique for endoscopists in the era of advanced endoscopy.

Nasopalpebral Lipoma sine Coloboma Syndrome-First Case Report

The nasopalpebral lipoma-coloboma syndrome was described for the first time in 1982. It is an autosomal dominant syndrome with complete penetrance and is characterized by features like congenital symmetric upper eyelid and nasopalpebral lipomas, bilateral symmetric upper and lower eyelid colobomas, broad forehead, widow's peak, abnormal eyebrow pattern, telecanthus, broad nasal bridge, maxillary hypoplasia, and ophthalmological abnormalities. We report a case of a milder variant of the nasopalpebral lipoma-coloboma syndrome that we have termed "nasopalpebral lipoma sine coloboma syndrome." Such a milder variant is not reported hitherto in the literature. We also describe the surgical correction of the deformity in a case that presented in adulthood, with a satisfactory and pleasing aesthetic outcome.

Vascular anomaly, lipoma, and polymicrogyria associated with schizencephaly: developmental and diagnostic insights. Illustrative case

BACKGROUND

Schizencephaly is an uncommon central nervous system malformation. Intracranial lipomas are also rare, accounting for approximately 0.1% of brain "tumors." They are believed to be derived from a persistent meninx primitiva, a neural crest-derived mesenchyme that develops into the dura and leptomeninges.

OBSERVATIONS

The authors present a case of heterotopic adipose tissue and a nonshunting arterial vascular malformation arising within a schizencephalic cleft in a 22-year-old male. Imaging showed right frontal gray matter abnormality and an associated suspected arteriovenous malformation with evidence of hemorrhage. Brain magnetic resonance imaging revealed right frontal polymicrogyria lining an open-lip schizencephaly, periventricular heterotopic gray matter, fat within the schizencephalic cleft, and gradient echo hypointensity concerning for prior hemorrhage. Histological assessment demonstrated mature adipose tissue with large-bore, thick-walled, irregular arteries. Mural calcifications and subendothelial cushions suggesting nonlaminar blood flow were observed. There were no arterialized veins or direct transitions from the arteries to veins. Hemosiderin deposition was scant, and hemorrhage was not present. The final diagnosis was consistent with ectopic mature adipose tissue and arteries with meningocerebral cicatrix.

LESSONS

This example of a complex maldevelopment of derivatives of the meninx primitiva in association with cortical maldevelopment highlights the unique challenges from both a radiological and histological perspective during diagnostic workup.

Deep Frontal Lipoma With Frontal Bone Invasion: Report of a Rare Case

Lipomas are benign masses of fatty tissue, and in the forehead, they may develop in the subcutaneous or deep fat tissue. While subcutaneous lipomas are common, deep forehead lipomas are unusual and rarely invade the underlying bone. Only a few cases have been reported in the literature, and even fewer cases are reported in children. We present a case of a slowly growing frontal mass corresponding to a deep lipoma responsible for frontal bone invasion, resulting in a bony defect reaching the dural space. Through this case, we aim to emphasize forehead lipomas' clinical and surgical characteristics.

Lipoma Arborescens Where MRI Is a Boon

Lipoma arborescens is a slow-progressing intra-articular benign lesion that typically affects the knee joint's suprapatellar recess. It occurs due to lipomatous proliferation of the synovium, giving a characteristic frond-like appearance. It is a rare cause of intermittent knee pain and joint effusion. We draw attention to this rare condition to increase the knowledge of its clinical symptoms and imaging characteristics, allowing for an early diagnosis and appropriate management. Magnetic resonance imaging (MRI) is considered the initial and the single imaging modality to evaluate this condition in the current era.

A Once-Thought Lipoma Turned Malignant Chondroid Syringoma

Chondroid syringoma is a relatively rare benign skin appendageal tumor with an incidence of <0.098%. Malignant chondroid syringoma (MCS) arises from cutaneous sweat glands and occurs on the extremities or trunk more commonly in women with only 51 reported cases. Due to the rarity of the disease and lack of published cases of MCS, the diagnostic criteria and treatment protocols are not clear. Based on available recommendations and histological criteria, MCS was diagnosed in a previously classified elbow lipoma following increased size and pain, and skin color changes in a 65-year-old woman.

Subdeltoid Lipoma Associated With Subscapularis Tear Successfully Treated With Arthroscopic Resection and Cuff Repair: A Case Report

A 61-year-old male patient presented with left shoulder pain and an associated lump. Magnetic resonance imaging revealed a subscapularis tear, and subdeltoid lipoma obliterated its insertion. He was successfully treated with arthroscopic subscapularis repair and resection of mass simultaneously.To the authors' knowledge, this will be the first documented case of lipoma occurring under the deltoid muscle associated with the subscapularis tear. The reported arthroscopic approach for resection of the subdeltoid lipoma provides a complete removal, minimal muscle dissection, limited surgical scar, and satisfying functional outcomes. Therefore, it may be considered an option for benign tumor resection in this area.

Tumor-to-bone distance and radiomic features on MRI distinguish intramuscular lipomas from well-differentiated liposarcomas

Background

To develop a machine learning model based on tumor-to-bone distance and radiomic features derived from preoperative MRI images to distinguish intramuscular (IM) lipomas and atypical lipomatous tumors/well-differentiated liposarcomas (ALTs/WDLSs) and compared with radiologists.

Methods

The study included patients with IM lipomas and ALTs/WDLSs diagnosed between 2010 and 2022, and with MRI scans (sequence/field strength: T1-weighted (T1W) imaging at 1.5 or 3.0 Tesla MRI). Manual segmentation of tumors based on the three-dimensional T1W images was performed by two observers to appraise the intra- and interobserver variability. After radiomic features and tumor-to-bone distance were extracted, it was used to train a machine learning model to distinguish IM lipomas and ALTs/WDLSs. Both feature selection and classification steps were performed using Least Absolute Shrinkage and Selection Operator logistic regression. The performance of the classification model was assessed using a tenfold cross-validation strategy and subsequently evaluated using the receiver operating characteristic curve (ROC) analysis. The classification agreement of two experienced musculoskeletal (MSK) radiologists was assessed using the kappa statistics. The diagnosis accuracy of each radiologist was evaluated using the final pathological results as the gold standard. Additionally, we compared the performance of the model and two radiologists in terms of the area under the receiver operator characteristic curves (AUCs) using the Delong’s test.

Results

There were 68 tumors (38 IM lipomas and 30 ALTs/WDLSs). The AUC of the machine learning model was 0.88 [95% CI 0.72–1] (sensitivity, 91.6%; specificity, 85.7%; and accuracy, 89.0%). For Radiologist 1, the AUC was 0.94 [95% CI 0.87–1] (sensitivity, 97.4%; specificity, 90.9%; and accuracy, 95.0%), and as to Radiologist 2, the AUC was 0.91 [95% CI 0.83–0.99] (sensitivity, 100%; specificity, 81.8%; and accuracy, 93.3%). The classification agreement of the radiologists was 0.89 of kappa value (95% CI 0.76–1). Although the AUC of the model was lower than of two experienced MSK radiologists, there was no statistically significant difference between the model and two radiologists (all P > 0.05).

Conclusions

The novel machine learning model based on tumor-to-bone distance and radiomic features is a noninvasive procedure that has the potential for distinguishing IM lipomas from ALTs/WDLSs. The predictive features that suggested malignancy were size, shape, depth, texture, histogram, and tumor-to-bone distance.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13018-023-03718-4.

Uncommon presentation of a giant psoas muscle lipoma: a case report and brief literature review

Giant retroperitoneal lipomas, particularly within the psoas muscle, are a rare condition. We herein present one such case of a 45-year-old Italian man and a literature review. There are only two case reports published in the literature, thus posing challenges for the appropriate diagnosis and treatment. Our patient was admitted to the emergency department with colicky abdominal pain. Computerized tomography (CT) with contrast enhancement revealed kidney stones and a 19.5×13.6×18 cm mass of adipose tissue with septa located in the right retroperitoneum, in close continuity with the right psoas major muscle. Magnetic resonance imaging showed a voluminous neoformation with predominantly adipose content and a compressive effect on adjacent vascular structures. The CT-guided biopsy indicated spindle cell mesenchymal neoplasm, not otherwise specified. Surgical resection of the retroperitoneal mass with the capsule was performed, and a histopathology examination confirmed the diagnosis of spindle cell lipoma. Despite the fact that CT and MRI are the main diagnostic tools, this case report emphasizes the need for a CT-guided core needle biopsy prior to surgery for appropriate diagnosis.

PTEN regulates proliferation and osteogenesis of dental pulp cells and adipogenesis of human adipose-derived stem cells

OBJECTIVE

To investigate the role of phosphatase and tensin homolog (PTEN) in dental pulp cells (hDPs) and adipose-derived mesenchymal stem cells (hADSCs).

MATERIALS AND METHODS

Genetic variant was identified with exome sequencing. The hDPs isolated from a patient with Cowden syndrome were investigated for their proliferation, osteogenesis, adipogenesis, and gene expression compared with controls. The normal hDPs and hADSCs were treated with the PTEN inhibitor, VO-OHpic trihydrate (VOT), to investigate the effect of PTEN inhibition.

RESULTS

A heterozygous nonsense PTEN variant, c.289C>T (p.Gln97*), was identified in the Cowden patient's blood and intraoral lipomas. The mutated hDPs showed significantly decreased proliferation, but significantly upregulated RUNX2 and OSX expression and mineralization, indicating enhanced osteogenic ability in mutated cells. The normal hDPs treated with VOT showed the decreases in proliferation, colony formation, osteogenic marker genes, alkaline phosphatase activity, and mineral deposition, suggesting that PTEN inhibition diminishes proliferation and osteogenic potential of hDPs. Regarding adipogenesis, the VOT-treated hADSCs showed a reduced number of cells containing lipid droplets, suggesting that PTEN inhibition might compromise adipogenic ability of hADSCs.

CONCLUSIONS

PTEN regulates proliferation, enhances osteogenesis of hDPs, and induces adipogenesis of hADSCs. The gain-of-function PTEN variant, p.Gln97*, enhances osteogenic ability of PTEN in hDPs.

Recurrent 8q11-13 Aberrations Leading to PLAG1 Rearrangements, Including Novel Chimeras HNRNPA2B1::PLAG1 and SDCBP::PLAG1, in Lipomatous Tumors

BACKGROUND/AIM

Structural abnormalities of chromosome bands 8q11-13, resulting in rearrangement of the pleomorphic adenoma gene 1 (PLAG1), are known to characterize lipoblastoma, a benign fat cell tumor, found mainly in children. Here, we describe 8q11-13 rearrangements and their molecular consequences on PLAG1 in 7 lipomatous tumors in adults.

MATERIALS AND METHODS

The patients were 5 males and 2 females between 23 and 62 years old. The tumors, namely five lipomas, one fibrolipoma and one spindle cell lipoma, were examined using G-banding with karyotyping, fluorescence in situ hybridization (FISH; three tumors), RNA sequencing, reverse transcription (RT) PCR, and Sanger sequencing analyses (two tumors).

RESULTS

All 7 tumors had karyotypic aberrations which included rearrangements of chromosome bands 8q11-13 (the criterion for selection into this study). FISH analyses with a PLAG1 break apart probe showed abnormal hybridization signals in both interphase nuclei and on metaphase spreads indicating PLAG1 rearrangement. RNA sequencing detected fusion between exon 1 of heterogeneous nuclear ribonucleoprotein A2/B1 (HNRNPA2B1) and exon 2 or 3 of PLAG1 in a lipoma and fusion between exon 2 of syndecan binding protein (SDCBP) and exon 2 or 3 of PLAG1 in a spindle cell lipoma. The HNRNPA2B1::PLAG1 and SDCBP::PLAG1 fusion transcripts were confirmed using RT-PCR/Sanger sequencing analyses.

CONCLUSION

As 8q11-13 aberrations/PLAG1-rearrangements/PLAG1-chimeras may evidently be a defining pathogenetic feature of lipogenic neoplasms of several histological types and not just lipoblastomas, we suggest that the term "8q11-13/PLAG1-rearranged lipomatous tumors" be generally adopted for this tumor subset.

Thyroglossal Duct Lipoma: A Case Report and a Systematic Review of the Literature for Its Management

Thyroglossal duct (TGD) remnants in the form of cysts or fistulas usually present as midline neck masses and they are removed along with the central body of the hyoid bone (Sistrunk's procedure). For other pathologies associated with the TGD tract, the latter operation might be not necessary. In the present report, a case of a TGD lipoma is presented and a systematic review of the pertinent literature was performed. We present the case of a 57-year-old woman with a pathologically confirmed TGD lipoma who underwent transcervical excision without resecting the hyoid bone. Recurrence was not observed after six months of follow-up. The literature search revealed only one other case of TGD lipoma and controversies are addressed. TGD lipoma is an exceedingly rare entity whose management might avoid hyoid bone excision.

MDM4 amplification in atypical lipomatous tumors/well-differentiated liposarcoma: Private event or alternative oncogenic mechanism?

Adipocytic tumors are the most common mesenchymal tumors in soft tissues. Among them, a diagnostic challenge relies in the distinction between lipoma and atypical lipomatous tumor (ALT)/well differentiated liposarcoma (WDLPS), as both entities are often undistinguishable not only from a radiological point of view, but also at the microscopic level and particularly when dealing with small tumor specimen. Thus, detection of recurrent MDM2 amplifications may be the only criteria to discriminate malignant tumors from lipomas. In this study, we report the case of a patient diagnosed with a well differentiated, adipocytic tumor located in the inferior limb and lacking MDM2 amplification, whose diagnosis was reclassified for ALT/WDLPS after identification of an alternative MDM4 amplification by comparative genomic hybridization profiling, whole exome sequencing and fluorescence in situ hybridization (FISH). Screening of a cohort of 37 large, deep-seated, well-differentiated adipocytic tumors previously classified as lipomas using RT-qPCR and FISH failed to detect other cases of MDM4-amplified ALT/WDLPS. This report shows that MDM4 amplification is an exceptional molecular event alternative to MDM2 amplification in ALT/WDLPS. This alteration should be considered and looked for in suspicious adipocytic tumors to optimize their surgical management.

MERRF Mutation A8344G in a Four-Generation Family without Central Nervous System Involvement: Clinical and Molecular Characterization

A 53-year-old man approached our Neuromuscular Unit following an incidental finding of hyperckemia. Similar to his mother who had died at the age of 77 years, he was diabetic and had a few lipomas. The patient's two sisters, aged 60 and 50 years, did not have any neurological symptoms. Proband's skeletal muscle biopsy showed several COX-negative fibers, many of which were "ragged red". Genetic analysis revealed the presence of the A8344G mtDNA mutation, which is most commonly associated with a maternally inherited multisystem mitochondrial disorder known as MERRF (myoclonus epilepsy with ragged-red fibers). The two sisters also carry the mutation. Family members on the maternal side were reported healthy. Although atypical phenotypes have been reported in association with the A8344G mutation, central nervous system (CSN) manifestations other than myoclonic epilepsy are always reported in the family tree. If present, our four-generation family manifestations are late-onset and do not affect CNS. This could be explained by the fact that the mutational load remains low and therefore prevents tissues/organs from reaching the pathologic threshold. The fact that this occurs throughout generations and that CNS, which has the highest energetic demand, is clinically spared, suggests that regulatory genes and/or pathways affect mitochondrial segregation and replication, and protect organs from progressive dysfunction.

A Giant Mixed Infiltrative Angiolipoma of the Back with Venous Malformation- A Case Report and Related Gene Mutation Detection

We report a case of a middle-aged male patient with a diffuse large mixed infiltrating angiolipoma on the back with venous malformation that grew from the age of 3 years. We discussed the design of the surgical flap for this large lipoma, observed its blood supply using SPY, and screened for possible causative genes, FCGR2A, BMP5, MUC2, and KRTAP4-9. To date, no invasive lipomas of this size and duration have been reported.

Spectrum of salivary gland diseases: A 24-year single-institution retrospective study

Introduction

Salivary glands are exocrine glands and are classified as major and minor salivary glands. Salivary gland pathologies are classified as neoplastic and non-neoplastic. The neoplasms of salivary glands can be benign or malignant.

Aim

The aim of the study was to describe the frequency of various salivary gland diseases reported in our institution from 1997 to 2021.

Methodology

This was a 24-year retrospective study of salivary gland lesions processed and reported by the Department of Oral Pathology and Microbiology. Data regarding age, gender, site, and diagnosis were obtained and studied.

Results

Amongst the total 5928 biopsied cases reported, 6% were salivary gland pathologies. Two hundred sixty-six were non-neoplastic lesions and 81 were neoplastic. The most common non-neoplastic lesion was mucous extravasation cyst. The most common neoplastic lesion was pleomorphic adenoma.

Conclusion

The frequency of occurrence of salivary gland lesions in the last 24 years of this institution is almost similar to that stated in other published studies.