Atypical lipoma of the right piriformis muscle: a case report and review of the literature.

BACKGROUND: Piriformis muscle mass is rare, which is particular for intrapiriformis lipoma. Thus far, only 11 cases of piriformis muscle mass have been reported in the English literature. Herein, we encountered one patient with intrapiriformis lipoma who was initially misdiagnosed. CASE PRESENTATION: The patient is a 50-year-old Chinese man. He complained of osphyalgia, right buttock pain, and radiating pain from the right buttock to the back of the right leg. Both ultrasound and magnetic resonance imaging demonstrated a cyst-like mass in the right piriformis muscle. Ultrasonography-guided aspiration was performed on this patient first, but failed. He was then recommended to undergo mass resection and neurolysis of sciatic nerve. Surprisingly, final histology revealed the diagnosis of intrapiriformis lipoma. The patient exhibited significant relief of symptoms 3 days post-surgery. CONCLUSION: Diagnosis and differential diagnosis of radicular pain are potentially challenging but necessary. Atypical lipoma is prone to be misdiagnosed, especially in rare sites. It is notable for clinicians to be aware of the presence of intrapiriformis lipoma to avoid misdiagnosis and inappropriate treatment.

Intraosseous myolipoma of the calcaneus.

A man in his 40s presented with an incidental finding of an osteolytic bone lesion. He sustained an ankle injury while inline skating, fracturing his lateral malleolus. Besides the fracture, radiographic imaging on the day of the injury incidentally revealed a well-defined solitary osteolytic lesion with a sclerotic rim within the right calcaneus. MRI showed an intraosseous, fat-containing lesion with focal contrast enhancement, assessed as an intraosseous lipoma with central necrosis. In the pathological analysis of a sample of the lesion an intraosseous myolipoma of the calcaneus was found-an unexpected and extraordinary finding. To prevent pathological fracturing, curettage and bone grafting were performed using autologous iliac crest bone in combination with allogenous bone chips.

Imaging diagnosis: CT characteristics of a retrobulbar hibernoma in a dog.

A 12-year-old female spayed Beagle was referred for investigation of exophthalmos. CT revealed a well-defined, retrobulbar mass causing rostro-dorsal displacement of the left globe. The mass had a mildly heterogeneous precontrast soft tissue attenuation with mild heterogeneous enhancement following iohexol administration. The mass was surgically removed en bloc with an orbital exenteration. Histopathology confirmed the mass to be a hibernoma, a benign tumor of brown adipose tissue. Hibernomas have CT characteristics consistent with both benign and malignant adipose tumors and may be underrecognized by radiologists.

Rapidly growing intramuscular lipoma: a unique entity of benign lipomas in children.

This report presents a case of an intramuscular lipoma observed in the left back of a healthy female toddler. It was resected after 3 months of observation because of rapid enlargement, raising suspicion of malignancy. Histopathological examination confirmed a diagnosis of intramuscular lipoma without malignant and blastemal components. Intramuscular lipomas are benign neoplasms that mostly appear as a rapidly growing tumour. Several hypotheses regarding the pathogenesis of this characteristic growth pattern have been proposed, including atrophy of the surrounding muscle, reactive adipocytic neoformation and multiple contractive interactions between the lipoma and the surrounding muscle.

Carpal tunnel syndrome secondary to a giant lipoma of the wrist and distal forearm.

In up to 2% of the population, benign tumours called lipomas can develop. When they are more than 5 cm, they are considered giant lipomas. Giant lipomas of the distal forearm and hand may cause compression to the underlying tissues, nerves and muscles, even though they are typically asymptomatic. An older woman with soft tissue swelling in her right wrist and forearm, and numbness and pain in her right hand presented to the general surgery outpatient clinic. Her numb fingers indicated that the median nerve was compressed, and an MRI scan of her wrist and forearm revealed median nerve compression due to a giant lipoma with a dimension of about 9.2×3.4×4 cm. A surgical excision was done with an intraoperative nerve stimulator, and the specimen sent for histopathology confirmed the diagnosis of lipoma. Pain, numbness and motor power improved within 1 week postoperatively, and the patient was discharged.

Metastasis from sarcoma with intracranial component referred on suspicion of lipoma or benign cyst.

This case report presents a 69-year-old male patient with a subcutaneous tumour in the left parietal region. Initially, the tumour was identified as a lipoma or benign cyst by the general practitioner. However, a subsequent MRI scan revealed a sarcoma metastasis with a significant intracranial component. Radical excision of the tumour was not possible due to its critical localisation. Therefore, the patient received palliative radiotherapy. This case emphasises the importance of accurate clinical assessment and highlights the clinical features that should lead to suspicion of malignancy.

A case of Wilson's disease combined with intracranial lipoma and dysplasia of the corpus callosum with review of the literature.

BACKGROUND: Wilson's disease (WD) is an inherited disorder of copper metabolism. Agenesis of the corpus callosum is the complete or partial absence of the major united fiber bundles connecting the cerebral hemispheres. Intracranial lipoma is an adipose tissue tumor resulting from an abnormal embryonic development of the central nervous system. The simultaneous occurrence of these three disorders is rare and has not been reported. This report focuses on the pathogenesis and association between the three disorders and highlights the importance of recognizing and effectively managing their coexistence. CASE PRESENTATION: The purpose of this study was to present a patient with coexisting WD, intracranial lipoma, and corpus callosum dysplasia. We reviewed a female patient hospitalized in 2023 with clinical manifestations of elevated aminotransferases and decreased ceruloplasmin, as well as genetic testing for an initial diagnosis of Wilson's disease. Subsequently, a cranial MRI showed corpus callosum dysplasia with short T1 signal changes in the cerebral falx, leading to a final diagnosis of Wilson's disease combined with intracranial lipoma and corpus callosum dysplasia. The patient's WD is currently stable after treatment with sodium dimercaptosulfonamide (DMPS) and penicillamine, and the patient's abnormal copper metabolism may promote the growth of intracranial lipoma. CONCLUSION: The pathogenesis of WD combined with intracranial lipoma and corpus callosum dysplasia is complex and clinically rare. The growth of intracranial lipomas may be associated with abnormal copper metabolism in WD. Abnormal copper metabolism affects lipid metabolism and triggers inflammatory responses. Therefore, early diagnosis and treatment are beneficial for improvement. Each new case of this rare co-morbidity is important as it allows for a better assessment and understanding of these cases' more characteristic clinical manifestations, which can help estimate the course of the disease and possible therapeutic options.

Nodular cystic fat necrosis: a distinctive rare soft-tissue mass.

We report the case of a 34-year-old female who was evaluated for a right lower extremity soft-tissue mass, found to be a large cystic lesion bound by fibrous tissue containing innumerable, freely mobile nodules of fat. Her presentation suggested the diagnosis of nodular cystic fat necrosis (NCFN), a rare entity that likely represents a morphological subset of fat necrosis potentially caused by vascular insufficiency secondary to local trauma. Her lesion was best visualized using MRI, which revealed characteristic imaging features of NCFN including nodular lipid-signal foci that suppress on fat-saturated sequences, intralesional fluid with high signal intensity on T2-weighted imaging, and a contrast-enhancing outer capsule with low signal intensity on T1-weighted imaging. Ultrasound imaging offered the advantage of showing mobile hyperechogenic foci within the anechoic cystic structure, and the lesion was otherwise visualized on radiography as a nonspecific soft-tissue radiopacity. She was managed with complete surgical excision with pathologic evaluation demonstrating, similar to the radiologic features, innumerable free-floating, 1-5 mm, smooth, nearly uniform spherical nodules of mature fat with widespread necrosis contained within a thick fibrous pseudocapsule. Follow-up imaging revealed no evidence of remaining or recurrent disease on postoperative follow-up MRI. The differential diagnosis includes lipoma with fat necrosis, lipoma variant, atypical lipomatous tumor, and a Morel-Lavallée lesion. There is overlap in the imaging features between fat necrosis and both benign and malignant adipocytic tumors, occasionally making this distinction based solely on imaging findings challenging. To our knowledge, this is the largest example of NCFN ever reported.

Case report: Pai syndrome with multiple ventricular septal defect and without cleft palate.

Pai syndrome is described as the association of a midline cleft lip, midline facial polyps, and lipoma of the central nervous system. However, only a few patients present the full triad, and most exhibit a wide spectrum of phenotypic variability. Its entire clinical spectrum is still poorly delineated and the etiology remains unknown. In this report, a newborn was presented with congenital nasal septal lipoma, lipoma of the corpus callosum, multiple ventricular septal defect, and additional minor facial dysmorphism. This entity, multiple ventricular septal defect, which has never been reported in PS. Cytogenetic analysis showed normal male 46, XY karyotype. Chromosomal microarray analysis (750 K array) was also unremarkable. This case draws attention with the presence of multiple ventricular septal defect in Pai syndrome and is important in terms of providing phenotypic diversity. To our knowledge, this is also the first genetically evaluated case of Pai syndrome from Turkey.

Huge Lipoma of Left Parotid Region with Intra-Parotid Extension.

Lipoma is a benign mesenchymal tumor originating from adipose tissue. The occurrence of this tumor in head and neck is less frequent and it rarely involves parotid gland. These are asymptomatic and occur both in the deep and the superficial lobe of the parotid. The most favored age group is from the fifth to sixth decade of life and is 10 times more common in the males. A 66-year-old male patient, with left parotid region lipoma is reported in this article. A fine-needle aspiration biopsy and ultrasonography were performed to establish the preoperative diagnosis and to plan the correct surgical approach. It was managed by surgical excision of lipoma with removal of cuff of superficial parotid tissue on superior aspect with preserving facial nerve. Follow-up examinations were planned to assess any facial nerve injury complications.

Parosteal lipoma of rib causing widening of intercostal space in an adolescent.

Parosteal lipomas are typically seen in adults and affect mostly the diaphysis of the long bones of the upper and lower limbs. Only a few cases have been reported in children until now and none were reported involving ribs. A female adolescent patient presented with swelling on the left upper back over the scapular region for the past 4 years without any neurological deficit. MRI revealed a hyperintense lesion on the left paravertebral region extending from D5 to D12 and into the intercostal space, causing it to widen. The patient underwent surgical excision. The lipomatous mass was seen entering in to the intercostal space, causing it to widen. However, the pleura was not breached. In this report, we have performed a literature review compiling all cases of parosteal lipoma affecting the ribs.

An unexpected encounter and outcome between endobronchial lipoma and carcinoma: a case report and literature review.

Bronchial lipoma is a rare benign tumor of the lung, which is often misdiagnosed due to concomitant pulmonary diseases. In addition, the coexistence of endobronchial lipoma and lung cancer is extremely unusual. To date, no related computed tomography (CT) images have been reported. The patient was a 53-year-old man, who was admitted to our hospital with cough, yellow phlegm, and fever for 1 week. The CT image showed an irregular mass in the medial segment of the right middle lobe (B4a) with surrounding ground glass opacity, and another solid nodule in the right lower lobe (B6b). Unfortunately, after 2 weeks of anti-inflammatory treatment, the bronchial invasion of the B4a nodule did not decrease significantly, so further bronchoscopy was carried out and tumor resection was performed using endoscopic mucosal resection with a ligation device (EMR-L). During the follow-up 4 months, it was found that the B6b nodule was marked enlargement and then removed. The lesions of the B4a and B6b were confirmed as endobronchial lipoma and squamous cell carcinoma (T1aN0M0) by histopathology and immunohistochemical staining, respectively, and no postoperative radiotherapy or chemotherapy was performed. Regrettably, after 29 months of follow-up, we observed recurrence and slow enlargement of the lipoma in its original location, progressive emphysema in both lungs, and solitary chest wall metastasis from the B6b squamous cell carcinoma that had been resected. Therefore, endobronchial endoscopy resection should be carefully selected for larger endobronchial lipoma. If it is accompanied by early squamous cell carcinoma (T1aN0M0), we still recommend active postoperative chemoradiotherapy.

Colo-colonic intussusception secondary to a lipomatous lesion in an asymptomatic patient.

Colo-colonic intussusception is a rare clinical condition in adults. The predominant aetiology of intussusception in adults is a pathological lead point, with malignant lesions being the most common type. Lipomas are benign tumours of adipocytes that can sometimes be difficult to diagnose without histopathological confirmation as we highlight with this case report. We report a case of an asymptomatic female patient in her 50s who presented with an intussusception due to a giant colonic lipoma. Her CT imaging showed the possibility of a low-grade liposarcomatous component or atypical lipomatous tumour component. A laparoscopic right hemicolectomy was performed due to intussusception with the possibility of leading to colonic obstruction as well as diagnostic uncertainty of the risk of malignancy. Histopathology confirmed the diagnosis of a lipomatous lesion. In cases such as this, early surgical management is appropriate to rule out malignancy and prevent emergency presentation and surgery.

A left intraventricular lipoma resected with the assistance of endoscopic camera.

Cardiac lipomas are extremely rare benign neoplasms of the heart. Most of them do not cause clinical symptoms, so far they are found incidentally in the majority of cases. Here, we describe a case of left intraventricular lipoma in an asymptomatic 34-year-old man which found by transthoracic echocardiography at comprehensive medical examination. Echocardiography and magnetic resonance imaging demonstrated a 3 × 3-cm mass in apical wall of the left ventricle, which was diagnosed as lipoma or liposarcoma. Although he was asymptomatic, tumor resection was indicated to confirm a diagnosis of the tumor and to prevent of future fatal complications. Surgery was performed with endoscopic assistance, and the tumor was resected. Histological examination of the tumor specimens consistent of lipoma. The patient is currently asymptomatic, and no recurrence was seen after 4 years.

Cardiac lipoma in left ventricle: A rare case diagnosed using imaging data.

Lipomas occuring within the heart are rare tumors, and invasive cardiac lipomas are even rare. Hereinafter we reported a case of a 51-year-old woman with a left ventricular transmural invasive lipoma, and summarized the imaging characteristics and main sites of it. Comprehensive imaging investigations appears valuable for early detection, intraoperative monitoring, and postoperative follow-up of invasive cardiac lipomas.

Saccular posterior cerebral artery aneurysm encased within a lipoma.

We present a case of a man in his 80s with an incidental posterior cerebral artery aneurysm encased within a lipoma. The literature surrounding the incidence and intricate relationship of lipomas to cerebral aneurysms is reviewed. Lipomas are proposed to be derived from maldifferentiated subarachnoid space. For this reason, lipomas are often associated with vascular malformations and may develop in conjunction with vascular malformations such as cerebral aneurysms. Hypothesised theories include the impediment of smooth muscle nutrient diffusion and the secretion of factors that weaken the arterial wall thereby predisposing to aneurysm formation. When lipomas neighbour cerebral vasculature, careful evaluation of the adjacent vessels should be conducted.