Sialolipomas of minor salivary glands: A multi-institutional study and literature review.

BACKGROUND: Sialolipoma is a rare histological variant of lipoma commonly misdiagnosed and composed of a proliferation of mature adipocytes with secondary entrapment of normal salivary gland tissue. The purpose of the present study is to report the clinicopathologic and immunohistochemical features of 10 new cases of sialolipomas in conjunction with a review of the literature. METHODS: A retrospective descriptive cross-sectional study was performed. A total of 54,190 biopsy records of oral and maxillofacial lesions from four oral and maxillofacial pathology services in Brazil were analysed. All cases of lipomas were reviewed, and clinical, demographic and histopathological data were collected of all cases compatible with sialolipomas. In addition, immunohistochemistry stains (AE1/AE3, CK7, 34ßE12, S-100, HHF35, α-SMA and Ki-67) and a literature review based on a search of three electronic databases (PubMed, Web of Science and Scopus) were performed. RESULTS: Among all lipomas reviewed, there were 10 cases of sialolipomas. The series comprised of 7 females (70.0%) and 3 males (30.0%), with a mean age of 46.1 ± 21.5 years (range: 11-71 years) and a 2.3:1 female-to-male ratio. The lower lip (n = 3, 30.0%) and tongue (n = 2, 20.0%) were the most common locations, presenting clinically as a nodule of slow growth and normal colour. Conservative surgical excision was the treatment in all cases. No recurrence was observed. CONCLUSION: Sialolipomas are a rare histological variant of lipoma, affecting the salivary glands, mainly in the parotid gland and palate of female adults. Pathologists must recognise sialolipomas to avoid misdiagnoses with other lipomatous tumours that can affect salivary glands.

Giant submandibular sialolipoma masquerading as huge goitre: a case report.

BACKGROUND: Sialolipoma is a rare tumour which may arise from both major and minor salivary glands and has recently been described as a variant of salivary gland lipomatous lesions. CASE PRESENTATION: We report a 54-year-old male who presented with a 7-year history of large right anterior neck swelling. He was clinically euthyroid and had no compressive or infiltrative symptoms. He sought medical attention due to the discomfort exerted by the weight of the mass and was keen for excision. The swelling appeared like a goitre but physical examination proved otherwise. Imaging was suggestive of a benign tumour arising from the right parapharyngeal fossa. The mass was surgically excised and was noted to be adherent to part of the submandibular gland. Histopathological examination revealed a new variant of benign adipocytic tumour of salivary gland or sialolipoma arising from the submandibular gland. Besides being the largest sialolipoma to be reported, there are also no reports of giant submandibular sialolipomas masquerading as a huge goitre in appearance. CONCLUSION: Submandibular sialolipomas can present in really large sizes and appear as a giant goitre. It is important to differentiate between benign lipomas from liposarcomas and tailor the management accordingly. Surgical enucleation is the preferred choice of treatment for these benign tumours with low recurrence rates.

Sialolipoma of Parotid Gland: A Case Report.

Sialolipoma is a rare tumor found within both major and minor saliva. Benign fatty tumors of parotid gland (lipomas) are very unusual, accounting for less than 0.5% of all parotid tumors. Sialolipoma, a distinct variant, is characterized by proliferation of mature adipocytes with secondary entrapment of normal salivary gland elements. Sialolipoma is well circumscribed and contains mature adipose tissue admixed with benign salivary gland component. We report a case of 51 years old female who presented with the complaint of swelling in the right parotid region for 12 years duration. Ultrasonography suggested adenoma and FNAC suggested a cystic lesion. Histopathological examination after superficial parotidectomy reported sialolipoma. The aim of this article is to report a case of sialolipoma, discuss the features and contribute to differential diagnosis. There are very few reported cases of sialolipoma in the existing English literature.

Sialolipoma of the parotid gland: A rare entity. Case report.

INTRODUCTION AND IMPORTANCE: Lipomatous neoplasms of the parotid gland represent an exceptionally rare and often underdiagnosed category of tumors, accounting for an incidence ranging from 0.6 % to 4.4 % of all neoplasms detected within the parotid gland. Sialolipoma is defined as an uncommon variant of lipoma, characterized by a well-defined proliferation of mature adipocytes with secondary entrapment of salivary gland elements, including serous acini, ducts, and myoepithelial cells. CASE PRESENTATION: The current case pertains to a 17-year-old female who presented with a one-year history of enlargement in the left preauricular region. CLINICAL DISCUSSION: The case we present poses a complex diagnostic challenge due to two distinct characteristics. The diagnostic challenge lies in its remarkably low incidence and the propensity for confusion with pleomorphic adenoma, which is the most common tumor of the parotid gland. It is a benign disease entity characterized by the absence of dysplasia, in marked contrast to pleomorphic adenoma. CONCLUSIONS: The infrequency in the manifestation of these tumor types, coupled with their prolonged asymptomatic course, can pose a diagnostic challenge. Enhancing our knowledge to comprehensively delineate these entities is imperative to effectively address the diagnostic complexities from both clinical and histopathological standpoints.

Endobronchial Sialolipoma: An Uncommon Salivary Gland Tumor at an Uncommon Site.

BACKGROUND: Sialolipoma is a benign neoplasm composed of neoplastic adipose tissue and normal salivary gland parenchyma. It is commonly seen in the parotid gland. The occurrence of sialolipoma in the main bronchus is exceedingly rare. CASE REPORT: A 52-year-old diabetic and hypertensive gentleman presented with shortness of breath and cough for the last 3-4 months. Computed tomography bronchial angiography showed a soft tissue lesion in the right intermediate bronchus causing its complete obliteration and subsequent collapse of the right lower lobe. A rigid tracheobronchoscope revealed a polypoidal growth originating in the right intermediate bronchus. Histopathology revealed a sialolipoma. The patient was doing well on follow-up and no recurrence was noted to date. CONCLUSION: The bronchus as the primary site for sialolipoma is unusual and has to be kept in the differential while dealing with the slow-growing endobronchial tumor.

Oncocytic sialolipoma of parotid gland: Case report and literature review.

Neoplastic lipomatous lesions of the salivary glands constitute ≤0.5% of all the salivary gland tumors. Oncocytic sialolipoma of the parotid glands is extremely uncommon. We report a case of oncocytic sialolipoma of the parotid gland in a 59-year-old male who presented with a gradually increasing swelling of the right parotid. Excisional parotid biopsy performed in view of possible pleomorphic adenoma as suggested on ultrasonography showed histological features consistent with oncocytic sialolipoma. We also described the characteristics of 24 previously reported cases of oncocytic sialolipoma of the parotid gland. The median age of the patients including the present case was 56 years (range 7-89), and 14 were male. The largest and the least reported sizes of the tumor were 7.0 and 1.4 cm, respectively. The left-sided parotid gland was more commonly involved (14/23). Despite its rarity, oncocytic sialolipoma should be considered in lipomatous parotid lesions showing epithelial components with oncocytic changes.

Oncocytic Lipoadenoma: Report of 3 Rare Cases Involving the Parotid Gland, Including a Synchronous Presentation With Paraganglioma of the Right Carotid Bifurcation and Literature Review.

Oncocytic lipoadenoma (OL) is a rare salivary gland tumor characterized by the presence of oncocytic cells and mature adipose tissue. To date, only 30 cases of OL have been reported in the English-language literature. We present 3 additional OL cases involving the parotid, including a synchronous presentation with paraganglioma of the right carotid bifurcation. Microscopically, both the OLs were composed of a mixed population of oncocytes and adipocytes in varying proportions surrounded by a thin, connective tissue fibrous capsule. Oncocytes were positive for pan-cytokeratins (CKs) AE1/AE3, epithelial membrane antigen, CK5, CK7, CK14, CK18, and CK19. Calponin, p63, alpha-smooth muscle actin, and carcinoembryonic antigen were negative. Vimentin and S-100 protein were positive only in adipose cells. Despite distinctive morphologic features, OL is often misdiagnosed, given its rarity. We hope to contribute to surgeons' and pathologists' awareness and knowledge regarding the existence of this tumor and provide adequate management through conservative surgical excision.

A rare case of recurrent congenital sialolipoma of parotid gland in a 3­year­old child: A case report and review of literature.

INTRODUCTION: Sialolipoma is an extremely rare salivary gland tumor characterized by a well circumscribed mass composed of glandular tissue and matures adipose elements. Herein,the aim of this article is to report the sixth case of congenital sialolipoma and the first case of recurrent congenital sialolipoma in infant, and discuss the clinicopathological and morphological features of sialolipoma and the possible cause of its recurrence. CASE REPORT: A 3 year-old child presented with a recurrent mass of right parotid gland which progressed from birth, initially treated at the age of 4 months by simple tumorectomy and excision of the surrounding parotid tissue. The tumor recurred 4 months postoperatively. The radiological examination confirmed the parotid origin of the tumor. Histopathology was consistent with a sialolipoma. A superficial parotidectomy with preservation of the facial nerve was performed this time at the age of 3 years. Postoperative recovery proceeded without incident with normal facial nerve function. There was no recurrence at 36-month follow-up. CONCLUSION: Although it is a very rare benign tumor, congenital sialolipoma should be kept in mind in the differential diagnosis of congenital parotid mass. The recurrence of congenital sialolipoma is dependent on its management, thus complete excision of the mass with the lobes of the salivary glands involved seems to be adequate for definitive management.

Endobronchial sialolipoma. Case report.

BACKGROUND: A 52-year-old woman presented with shortness of breath and cough. An endobronchial sialolipoma was found at the left entrance of the main bronchus. Sialolipoma is an exceedingly rare type of lipoma reported of the minor salivary glands, especially within the bronchus. CASE PRESENTATION: A 52-year-old woman presented with shortness of breath and cough with 6 months´ evolution. Endobronchial endoscopy revealed a tumour at the left entrance of the main bronchus. The entire removal of the tumour was removed using a cryoprobe device. Pathological examination showed a tumour consistent with the diagnosis of sialolipoma due to the presence of mature adipose cells blended with acinar, ductal, basal, and myoepithelial cells. The patient had a favourable outcome. CONCLUSION: The infrequent tracheobronchial presentation of this tumour can be challenging for correct diagnosis.

Supraglottic subepithelial benign mass lesions: Focus on clinical features of sialolipoma-like lesion.

OBJECTIVES: Sialolipoma has been classified as a benign soft tissue lesion in the 2017 World Health Organization classification of head and neck tumors. To our knowledge, only one case of laryngeal sialolipoma has been reported in the English literature. We conducted a retrospective study to identify clinical characteristics of supraglottic sialolipoma-like lesion and differentiate it from other supraglottic subepithelial masses. METHODS: Medical records of 16 patients with supraglottic subepithelial benign mass lesions who underwent histological evaluation between 2003 and 2019 were retrospectively analyzed. Sialolipoma-like lesion was defined as a local finding of a well-circumscribed gross mass with pathological presence of salivary gland-like parenchymal lobules with evenly interspersed adipose tissue. RESULTS: Eight patients showed histological positivity for sialolipoma-like lesion, 3 for amyloidosis, 2 for hemangioma, and 1 each for cyst, lymphoid hyperplasia, and chondrometaplasia. Sialolipoma-like lesion tended to be predominant among men; those affected had a mean age of 52.8 (range, 39-74) years. By contrast, among patients with amyloidosis, the ratio of men to women was 1:2 (100% vs. 33%; p = 0.055). Fiberscopic examination of all patients with sialolipoma-like lesions identified well-circumscribed, yellowish masses, closely resembling local amyloidosis findings. Sialolipoma-like lesion was associated with a significantly higher body-mass index (BMI; 27.4 ± 2.8 kg/m2) than amyloidosis (21.6 ± 1.4 kg/m2; p = 0.014). The transoral approach was used for lesion resection in all patients with sialolipoma-like lesion. No patient experienced postoperative recurrence. CONCLUSION: Laryngeal sialolipoma-like lesion might be more prevalent than was previously reported, and histological examination is important to differentiate it from amyloidosis. Supraglottic sialolipoma-like lesion must be differentially diagnosed in patients with high BMI presenting with well-circumscribed, yellowish supraglottic masses.

Adipocytic tumors of orofacial region: Clinicopathologic appraisal of ten cases with a review of its variants.

Lipomas are the most common benign tumors. However, their presence in oral cavity is albeit erratic. Even scarcer is the prevalence of the various histopathological variants. We, hereby, report the wide range of clinical and histopathologic presentations of these uncommon entities affecting the orofacial region. Discussed herein are six cases of lipomas, two cases of intramuscular lipomas and one case each of osteolipoma and sialolipoma.

Giant Congenital Sialolipoma of Parotid Gland with Parapharyngeal Extension.

INTRODUCTION: Sialolipoma is an extremely rare salivary gland tumor characterized by a well circumscribed mass composed of glandular tissue and mature adipose elements. Herein our aim was to present the fifth case of congenital sialolipoma, which was firstly followed up as a parotid gland hemangioma, and underline the fact that sialolipomas should be kept in mind in the differential diagnosis of congenital parotid gland masses. CASE REPORT: A 10-month old male presented with a left-sided huge neck mass which progressed after birth. Radiologic examination revealed a tumor originating from the parotid gland filling the parapharyngeal space. Histopathologic examination of an incisional biopsy was consistent with sialolipoma. A total parotidectomy with preservation of the facial nerve was performed at the age of 1 year. The postoperative recovery was uneventful with normal facial nerve function. There was no recurrence at the 24-month follow-up. CONCLUSION: Although it is a very rare benign tumor, congenital sialolipoma should be kept in mind in the differential diagnosis of congenital parotid mass.

Oncocytic Sialolipoma of Parotid Gland: Case Report and Literature Review.

Oncocytic sialolipoma is a very rare tumor of which only three cases have been reported. This entity is considered to be a variant of sialolipoma which harbours oncocytic nodules within a well-circumscribed lipomatous mass. We report a parotid mass in 73-year-old female that was difficult to diagnose in imaging and on biopsy. Ultrasonography and MRI demonstrated a mass with features thought to be consistent with lipoma. Twice needle core biopsies were performed. Both were indefinite for diagnosis. The first report favoured a lipoma and the second report suggested the lesion represented oncocytic hyperplasia or an oncocytoma. The microscopic examination of the excised surgical specimen demonstrated typical features of oncocytic sialolipoma, characterized by a predominately lipomatous component, sparse normal-appearing salivary gland tissue and multiple oncocytic nodules. This is the second case of oncocytic sialolipoma reported to occur in the parotid gland.

Sialolipoma of Parotid Gland a Rare Histological Presentation.

Sialolipoma is a rare tumour found within both major and minor salivary glands, it is recently described as a variant of salivary gland lipoma. Sialolipoma was first described by Pusiol et al. (Indian J Pathol Microbiol 52(3):379-382, 2009). Sialolipoma is well circumscribed and contains mature adipose tissue admixed with benign salivary gland component. We report a case of 62 years old female who presented with the complaint of swelling in the right parotid region for 5 years duration. Apart from cosmetic reason she had no other complain. All specific investigations done were inconclusive and suggested a benign tumor. Histopathological examination after superficial parotidectomy suggested sialolipoma. As newly described tumor type, care should be taken to distinguish oncocytic sialolipoma from other salivary gland neoplasms such as simple lipoma, pleomorphic adenoma, or oncocytoma.

Sialolipoma of parotid gland in a 1-year-old male child: A case report and review of literature.

Sialolipoma is a recently described rare histological variant of lipoma, characterized by well-demarcated proliferation of mature adipocytes with secondary entrapment of salivary gland elements. Less than forty cases of sialolipoma have been reported in English literature. This tumor has been reported both in major and minor salivary glands, with the parotid gland being the most common site. Age incidence in this tumor varies from 0 month to 84 years. However, the occurrence of this tumor in an infant is very rare. In the published literature, the size of this tumor varied from 1 to 7 cm. In the present case, the tumor size was >7 cm. To the best of our knowledge, congenital sialolipoma >7 cm has been rarely reported earlier. Hence, this case is presented because of its rarity and unusual gross appearance.

Lipomatosis of the parotid salivary gland: 2 case reports and review of the literature on fat-containing salivary gland lesions.

Two cases of lipomatosis of the parotid salivary gland in two dogs are reported. Both dogs were presented with a slow growing unilateral non-painful mass in the parotid region. The mass measured 12 and 15 cm on the longest axis for case 1 and 2 respectively. Initial incisional biopsies were suggestive of infiltrative lipoma or salivary gland adenocarcinoma. Case 2 underwent head radiographs that showed a soft tissue opacity on the area of the right parotid gland followed by a computed tomography that showed a multi-lobulated infiltrative mass occupying the right parotid gland. Both cases underwent total parotidectomy with an excisional biopsy intent. Surgery on case 1 included total ear canal ablation (TECA). Histology revealed lipomatosis of the parotid gland with a similar admixture of adipocytes and well-differentiated salivary acini on both cases. No recurrence was reported by 4 years for case 1 and by 3 years for case 2. Case 1 developed long-term right-sided facial paralysis and palpebral reflex deficit due to damage of the facial and trigeminal nerve during surgery. The cases are described and the veterinary literature is reviewed in view of the most updated information available in human medicine on fat-containing salivary gland lesions. Considering this literature review, authors recommended these two cases to be classified as lipomatosis of the salivary gland. In conclusion, fat-containing salivary gland lesions should be considered in the list of differential diagnoses in dogs with an enlarged salivary gland and seem to be associated with an excellent prognosis after surgical excision.

Sialolipoma of the Superficial Lobe of the Parotid Gland: A Case Report and Literature Review.

Sialolipoma of the parotid gland is very rare. We report a case of a 38-year-old woman who presented with a painless, slowly growing, mobile lump of the parotid gland. Computed tomography revealed lipoma of the superficial lobe of the parotid gland. Superficial parotidectomy was performed with uneventful postoperative course. The histology showed sialolipoma. Review of the 25 reported cases (including our case) of parotid sialolipoma shows that this tumor is more common in the fifth decade of life, on the left side and the superficial lobe. It has a slight preference for men. Its clinical presentation mimics the standard (pure) parotid lipoma and other more common benign parotid tumors particularly pleomorphic adenoma and Warthin's tumor. Surgical excision is curative with minor complications and small recurrence rate. Histological examination is necessary to establish the diagnosis and to exclude malignancy.

Vascular changes in hard palate sialolipoma: Sialoangiolipoma or vascular malformation?

Palate sialolipomas are rare. Less than 10 cases located in the hard palate are reported to our knowledge. We report a case of hard palate sialolipoma, peculiar by the intratumor vascular patterns. A 67-year-old man presented with a 1.5 cm lesion of the oral hard palate. The lesion was surgically resected. On microscopy, the lesion, partly encapsulated, consisted of a proliferation of mature adipocytes containing normal minor salivary gland tissue and branching intratumoral vessels of varied size with irregularly thickened wall and papillary projections or tufts. The microscopic features of the tumor we report suggest that vascular malformation-like patterns may occur in sialolipomas of the hard palate. This morphological vascular peculiarity should be acknowledged since it may represent source of hemorrhage.

Sialolipoma of minor salivary glands: presentation of five cases and review of the literature with an epidemiological analyze.

UNLABELLED: Sialolipoma is rare benign neoplasm arise from salivary glands (majors and minors) characterized by neoplastic adipose tissue with scattered non-neoplastic salivary gland acinus. To date 60 cases (including 5 cases reported in the present paper) have been reported in scientific literature. This article presents 5 new cases of sialolipoma affecting minor salivary glands (MiSG) and additionally reviews and analyzes the previously published cases to assess possible demographical differences between sialolipoma from minor and from major salivary glands. CASE REPORTS: 5 cases (3 females; 2 males; age means 63.8 years), of sialolipoma from MiSG, are reported. 2 of them were located in buccal mucosa, 1 in upper lip mucosa, 1 in floor of the mouth and 1 in retromolar area. All tumors were composed by neoplastic adipocytes cells interlaced with normal salivary gland acinus cover it by a fibrous tissue capsule. Analyzes of literature showed that MiSG sialolipoma is most frequent in females over 60 years old, therefore and in conclusion this article assess different demographical profile of sialolipoma in respect to their topography.

Oncocytic sialolipoma of the submandibular gland.

Sialolipoma, a rare tumor of the salivary gland, is a recently described variant of salivary gland lipoma. Oncocytic sialolipoma was first described by Pusiol et al. in 2009. We report the case of an oncocytic sialolipoma of the submandibular gland in a 43-year-old female. Excision of the tumor was performed with preservation of the submandibular gland. The tumor had a thin, fibrous capsule and consisted of abundant adipose tissue, an oncocytic nodule, and scattered normal glandular structures surrounded by adipose tissue. Four cases of sialolipoma of the submandibular gland, including the present case, were reviewed. All 4 tumors were developed on the right submandibular glands, with a composition of adipose tissue as high as that of sialolipoma of the parotid gland; in contrast to previous reports, three cases were in females. As newly described tumor type, care should be taken to distinguish oncocytic sialolipoma from other salivary gland neoplasms such as simple lipoma, pleomorphic adenoma, or oncocytoma.