Oncocytic lipoadenoma of the parotid gland: a report of a new case and review of the literature

Oncocytic lipoadenoma is a rare salivary gland tumour composed of adipose tissue and oncocytic epithelial cells in varied proportions. This tumour is still not included in the current WHO classification of salivary gland neoplasms. We herein report a further case of oncocytic lipoadenoma originating in the parotid gland of a 55-year-old woman. The tumour presented as a slowly growing asymptomatic left-sided parotid gland mass. The resected tumour measured 2.7 cm in maximum diameter and was composed of oncocytoma-like epithelial component admixed with mature adipocytes that made up 10% of the whole mass. Foci of sebaceous differentiation were seen. This rare variant of lipomatous salivary gland tumours is in need of more recognition and should be distinguished from other fat-containing salivary gland lesions, particularly lipomatous pleomorphic adenoma and myoepithelioma.     

Lymphadenoma: a report of three cases of an uncommon salivary gland neoplasm

AIMS: Lymphadenoma of the salivary gland is a rare neoplasm that has not been properly characterized. This study describes the clinicopathological features of three cases. METHODS AND RESULTS: All three patients were males, ranging in age from 13 to 57 years. Two presented with a parotid mass, and one a preauricular mass. The tumours were well circumscribed, comprising anastomosing trabeculae, solid tubules, glands or basaloid islands of epithelium with or without cyst formation, accompanied by a prominent lymphoid stroma lacking sinuses. Large reactive lymphoid follicles were found in two cases. The epithelial cells were bland-looking to mildly atypical. Immunostaining demonstrated dual luminal cell and abluminal basal cell differentiation, with the former being often subtle and highlighted only by immunostaining for epithelium membrane antigen or CAM 5.2, and the latter being highlighted by p63 immunostain. CONCLUSIONS: Although there is some variation in the histological pattern from case to case, lymphadenoma is a morphologically recognizable salivary gland adenoma characterized by a dense lymphoid infiltrate. Lack of familiarity with this tumour may lead to misdiagnosis as myoepithelial sialadenitis, lymphoma, metastatic carcinoma in lymph node or lymphoepithelial carcinoma.     

Polymorphous low-grade adenocarcinoma of the major salivary glands: report of three cases in an unusual location

AIMS: Polymorphous low-grade adenocarcinoma (PLGA) is the second most common type of malignant neoplasm in minor salivary glands. Its origin in major salivary glands is considered exceedingly rare. Herein, we present three cases of de novo PLGA arising in major salivary glands. METHODS AND RESULTS: Three cases of PLGA were identified in a large series of primary tumours of major salivary glands. We investigated their clinicopathological profiles, including immunohistochemical features. The three patients (two men and one woman) were 51, 65, and 79 years old. The tumours were 20-30 mm large; two were in the parotid gland and one in the submandibular gland. Histologically, all the tumours had a polymorphous architectural pattern showing predominantly solid, tubular, and cribriform features and invasive growth. Papillary areas were observed focally in two tumours and an 'Indian-file' array in one. The tumour cells had a bland cytological appearance and low mitotic count. Two tumours showed perineural invasion. No preexisting pleomorphic adenoma component was identified. In all cases, tumour cells were positive for epithelial markers, S100 protein, and vimentin but negative for alpha-smooth muscle actin, muscle-specific actin, and glial fibrillary acidic protein. Proliferative activities assessed with the Ki67 labelling index were 4.3%, 7.1%, and 7.6%; no p53 overexpression was observed. Two patients had local recurrence, but none had metastasis or died of tumour. CONCLUSIONS: PLGAs arising in major salivary glands and those in minor salivary glands have similar clinicopathological and immunohistochemical characteristics. It is important to recognize that PLGA can occur ab initio in the major salivary glands, although it is extremely rare.     

Cribriform adenocarcinoma of minor salivary gland: A report of two cases with an emphasis on cytology

Cribriform adenocarcinoma of minor salivary gland (CAMSG) is a recently characterized low grade salivary gland malignancy that most commonly presents as a mass in the base of the tongue, frequently with regional lymph node metastasis. Given its relative rarity and overlapping cytomorphology, CAMSG may be confused with polymorphous low grade adenocarcinoma (PLGA) in minor salivary gland sites and papillary thyroid carcinoma (PTC) in cervical metastasis, in both fine‐needle aspiration and excisional specimens. As there are no cytology reports in the literature, we present two new cases of CAMSG and describe the aspiration cytology of the tumor taken from bench top aspirates, compare it with the histomorphology, and discuss the features that may help one avoid misdiagnosis of PTC in the setting of cervical lymph node metastasis. We found that like PTC, aspirates of CAMSG contain polymorphic fragments of epithelial cells arranged in monolayer sheets, papillary fronds and tips, and occasional cribriform configurations, and metachromatic stromal fragments, which may be misinterpreted as colloid. A background of myxoid/mucoid material also reminiscent of colloid was prominent. Differentiation from PLGA is more difficult based strictly on cytology. A review of the most current literature in relation to the molecular and immunohistochemical profiles, therapeutic options, and prognosis is also presented. It is critical for pathologists and clinicians to be aware of this tumor when presented with patients having a cervical lymph node mass in the absence of a primary tumor. Diagn. Cytopathol. 2014;42:1085–1090. © 2014 Wiley Periodicals, Inc.     

Localization of prostate-specific antigen-like immunoreactivity in human salivary gland and salivary gland tumors

Immunoreactivity of prostate-specific antigen (PSA), a kallikrein-like enzyme present in the seminal plasma, was demonstrated by indirect immunoperoxidase staining using a PSA antiserum in the apical cytoplasm along the luminal border of small-sized duct epithelial cells of the major salivary (parotid and submandibular) gland of both sexes (56/56, 100%). No PSA-like immunoreactivity was seen in large-sized duct epithelial cells and acinar cells. Minor salivary gland ducts were negative. When inflammatory and atrophic changes were observed, ductal expression of PSA-like immunoreactivity was decreased (12/37, 32%) and the site of intracellular localization often became diffusely cytoplasmic. The immunoreactivity was absorbed by human seminal plasma. Immunoreactivities of prostatic acid phosphatase and sex hormone receptors were undetectable in the salivary gland. Twenty-nine (34%) of 86 salivary gland tumors with ductal differentiation were immunoreactive for PSA mainly in the cytoplasm. A PSA monoclonal antibody ER-PR8 detected immunoreactivity in the prostate but not in the salivary glands or their tumors. Prostate-specific antigen-like immunoreactivity in small-sized (intercalated) duct epithelial cells of the major salivary gland and their tumors may be due to cross-reactivity of the antiserum with kallikrein-like substances.     

Chondroid lipoma of the parotid gland

The presence of a parotid tumour containing cartilage immediately invokes a diagnosis of pleomorphic adenoma. However, the case we wish to highlight is a rare primary parotid neoplasm composed of both immature and mature fat and cartilaginous-looking areas conforming histologically to a chondroid lipoma.This lesion is a well-circumscribed, lobulated tumour composed of mature fat, mono- and multi-vacuolated lipoblastic-like cells suspended in a chondromyxoid matrix, simulating a cartilaginous tumour. There is no cytological atypical thus separating it from malignant fat and cartilaginous tumours. Chondroid lipomas do not show epithelial differentiation and exhibit only focal cytokeratin immunoexpression, thereby allowing for separation from pleomorphic adenoma and myoepithelioma.     

Fine needle aspiration biopsy of intraparotid spindle cell lipoma: A case report

Intraparotid spindle cell lipoma (SCL) of the salivary gland is a rare entity. Review of the literature revealed only two previous reports describing its cytological features. We report a case of a 44‐year‐old man who complained for a slowly growing, asymptomatic mass in the left parotid gland that since 12 months. Fine needle aspiration biopsy (FNAB) showed a loose collections of bland‐appearing spindle cells in a myxoid background admixed with capillary fragments and some mature fat cells suggesting a diagnosis of SCL. A cytological diagnosis of mesenchymal myxoid spindle cell tumor with lipomatous differentiation, possibly an intraparotideal SCL was performed. Histological examination of the mass and the positive immunostaining for CD34 and negativity for S‐100, CK‐cocktail, and actin confirmed the diagnosis of SCL. The diagnosis of intraparotid SCL can be made by examining cytologic material containing mature fat with bland spindle cells in a myxoid background. FNAB diagnosis on SCL also allows to rule out other primary salivary gland tumors that may be clinically and instrumentally indistinguishable and thereby permits an appropriate surgical procedure to ensue. Diagn. Cytopathol. 2013. © 2011 Wiley Periodicals, Inc.     

Merkel cell carcinoma of the parotid gland associated with Warthin tumour: report of two cases

AIMS: Two cases of Merkel cell carcinoma occurring simultaneously and in close association with a Warthin tumour of the parotid gland are reported. METHODS AND RESULTS: The patients were a 65-year-old man and a 70-year-old man, respectively. The Merkel cell carcinoma component was immunoreactive for chromogranin and keratin 20 and contained neuroendocrine-type granules at the ultrastructural level. CONCLUSIONS: The histogenesis of this heretofore undescribed combination is discussed.     

Usefulness of minor salivary gland biopsy in the diagnosis of IgG4-related disease: a case report

Although considered essential for diagnosing IgG4-related disease (IgG4-RD), biopsy of target organs is often difficult to perform. Such was the case of a 56-year-old man admitted with general malaise and weight loss. Computed tomography revealed swelling of the submandibular gland, mild dilatation of the main pancreatic duct, renal involvement, periaortitis, and swelling of the lymph nodes in the abdominal cavity. Laboratory testing revealed elevated serum IgG4 level. These findings were suggestive of IgG4-RD; however, the patient refused consent for biopsy of the target organs for a definitive diagnosis for the invasiveness. Therefore, we tried to perform a biopsy from minor salivary gland, which revealed no sign of clinical abnormality because the biopsy is not an invasive diagnostic procedure. As a result, the biopsy revealed significant IgG4-positive plasma cell infiltration, allowing for definitive IgG4-RD diagnosis. Administration of oral prednisolone (30 mg/day) effectively improved all symptoms. These findings indicate that minor salivary gland biopsy is an effective means of IgG4-RD diagnosis in patients for whom biopsy of target organs is difficult even if there were no sign of clinical abnormality in appearance.     

Stromal melanocytosis of an adenoid cystic carcinoma arising from the palatal minor salivary gland

An unusual case of adenoid cystic carcinoma arising from the palatal minor salivary gland in a 63-year-old Japanese female is reported. In addition to the characteristic histopath-ologic features of adenoid cystic carcinoma, spindle- and dendritic-shaped cells containing excessive amounts of melanin pigment were densely and widely distributed in the stroma resulting in a blue nevus-like appearance. Neither melanocytes nor melanin pigments were seen within the parenchyma. The possible histogenesis of melanocytes in the stroma of the salivary gland carcinoma is discussed, although no firm conclusion could be drawn.     

Mucoepidermoid carcinoma arising in Warthin's tumour of the parotid gland: report of two cases with histopathological, ultrastructural and immunohistochemical studies

Aims : Malignant transformation of Warthin's tumour (WT) is a rare event. We present two cases of mucoepidermoid carcinoma (MEC) arising in WT in the parotid gland.  

Methods and results

Two cases of MEC arising in WT, which were found in 185 cases of WT of the parotid gland, were investigated by light and electron microscopy, and immunohistochemistry. Both cases had largely similar macroscopic and histological features with some differences. Histologically, the tumours consisted mainly of WT with multilayered hyperplastic arrangements of oncocytic cells and focal squamous and goblet cell metaplasia. In the same tumour mass, however, the features of MEC were observed with invasion to adjacent adipose tissue. A transitional zone between WT and MEC was evident. Both patients were alive and well without evidence of recurrence 30 and 34 months after surgery, respectively. Electron microscopy revealed that cyst lining epithelial cells in WTs had abundant mitochondria whereas some of the MEC cells contained numerous tonofilaments and mucinous granules. Immunohistochemically, oncocytic cells of WTs were strongly positive for mitochondria and Salyl-Tn was extensively stained in MECs. The labelling index for Ki67 was obviously higher in the carcinoma cells than the epithelial cells of WT.  

Conclusions

Our cases confirmed the possibility of malignant transformation of the epithelial component in WT to MEC.     

腮腺非皮脂腺淋巴腺瘤2例并文献复习

目的：探讨非皮脂腺淋巴腺瘤( nonsebaceous lymphadenoma, NSL)的临床病理学特征、诊断及鉴别诊断。方法分析2例NSL的临床病理学特征、组织学形态及免疫表型并复习相关文献。结果2例NSL均为成年女性。镜检：肿瘤主要由上皮成分及间质增生的淋巴组织混合形成,与周围腮腺组织界限清楚,由纤维结缔组织分隔,间质内可见增生的淋巴滤泡。上皮成分可由囊腔、实性岛状、梁状或腺管样结构组成,其中囊腔及腺管样结构由两种细胞成分构成,腔面细胞及外层细胞,囊腔内含伊红不定形物及偶见的泡沫细胞,上皮细胞无皮脂腺分化,形态温和,无非典型性,未见核分裂象。其中1例见完整的纤维被膜包绕整个肿瘤,被膜下见窦结构。免疫表型：上皮细胞CK(AE1/AE3)和CK7阳性,囊腔、腺管样结构的外层细胞p63、CK34βE12和CK5/6阳性。结论 NSL是一种罕见的涎腺良性肿瘤,位于淋巴结内的病变报道较少,组织学结构的多样性使其易与一些涎腺病变相混淆,与一些恶性肿瘤的鉴别尤为重要。     

Oncocytic lipoadenoma of the parotid gland: Cytological findings and differential diagnosis on fine‐needle aspiration

Oncocytic lipoadenoma is a rare benign neoplastic lesion of salivary gland. To the best of our knowledge, the detailed cytomorphological findings were described only in two cases. We are reporting a 56‐year‐old woman who presented with 1‐year history of right parotid gland mass. Cytologic examination revealed tight clusters of bland looking oncocytic ductal cells with few aggregates of mature adipose tissue in a lipoid background and a benign oncocytic tumor of parotid gland was rendered. Histologically, a tumor with islands of oncocytic epithelial cells admixed with abundant mature adipose tissue was identified. Oncocytic lipoadenoma despite its rarity should be considered in the differential diagnosis of salivary gland fine‐needle aspirations containing oncocytes especially those which are accompanied by mature adipose tissue and lipoid background. Diagn. Cytopathol. 2015;43:72–74. © 2014 Wiley Periodicals, Inc.     

Congenital tumours of the salivary gland: a case report and review

A congenital epithelial tumour of the submandibular salivary gland, occurring in a child of 10 months, is described. The lesion appeared benign and consisted of basal type cells, showing ductal and acinar differentiation with myoepithelial cells. The associated fibrous stroma contained blood vessels and small nerve bundles. A few similar lesions have been reported in the past, some of which showed features of malignancy. Although various names have been proposed, we suggest that these lesions represent a single group derived from a primitive cell line and advocate the use of the term sialoblastoma.     

Aggressive invasive micropapillary salivary duct carcinoma of the parotid gland

The presence of invasive micropapillary component has been reported to be associated with salivary duct carcinoma and poor outcomes. Herein is described a rare case of invasive micropapillary salivary duct carcinoma of the parotid gland in a 60-year-old man. The micropapillary component was approximately 70% of the area of the tumor. Squamous differentiation was focally seen adjacent to the micropapillary component. On immunohistochemistry the ordinary salivary duct carcinoma component was positive for gross cystic disease fluid protein-15 (GCDFP-15), androgen receptor (AR), and HER2/neu, whereas both micropapillary and squamous components were negative for GCDFP-15 and AR. Immunohistochemical staining for D2-40 highlighted the lymph vessel invasion of tumor cells. This patient developed metastases in the lymph nodes of the neck, and also in the liver, lung, and brain. The lymph nodes and liver metastases had both ordinary salivary duct carcinoma and micropapillary components. The patient died of tumor 11 months after the initial surgical operation. The results support that the presence of micropapillary component is associated with more aggressive behavior of salivary duct carcinoma. It is also important for pathologists to recognize that GCDFP-15 and AR expression can be reduced in micropapillary carcinoma in the differential diagnosis of metastatic tumor.     

Reporting of fine needle aspiration (FNA) specimens of salivary gland lesions: A comprehensive review

Currently, there is no uniform classification scheme available for reporting of salivary gland fine‐needle aspiration (FNA) specimens. Recently, an International group of pathologists has recommended a tiered classification scheme for reporting of salivary gland FNA results known as the “Milan System for Reporting Salivary Gland Cytopathology (MSRSGC).” We performed a comprehensive review of the published literature on FNA of salivary gland lesions by employing the diagnostic categories of the MSRSGC to evaluate their reliability in the management of salivary gland lesions. A comprehensive review of the literature was carried out through PubMed from 1987 to 2015 to identify studies which categorized the cytologic diagnoses and included surgical follow‐up. Only cases with histopathologic follow‐up were included in the analysis. Twenty‐nine studies comprising 4514 cases of salivary gland FNAs with surgical follow‐up were included in this study. The cytologic diagnoses were categorized into the following categories proposed by MSRSGC. The number of cases in each diagnostic category and the risk of malignancy (ROM) were as follows: Non‐Diagnostic—100 cases (ROM‐ 25.0% ± 16.7%), Non‐Neoplastic—587 cases (ROM: 10.2% ± 5.5%), Benign Neoplasm −2673 cases (ROM: 3.4% ± 1.3%), Salivary Gland Neoplasm of Undetermined Malignant Potential (SUMP)—64 cases(ROM: 37.5% ± 24.7%), Suspicious for Malignant neoplasm—70 cases(ROM: 58.6% ± 19.5%), and Malignant—1012 cases(ROM: 91.9% ± 3.5%). A tiered classification scheme as proposed by MSRSGC may prove helpful in effectively guiding clinical management of patients with salivary gland lesions.     

Cytologic diagnosis of salivary duct carcinoma: A review of seven cases

The cytomorphologic findings in fine-needle aspirates from 7 cases of salivary duct carcinoma (SDC) are reviewed and correlated with the histologic features. Malignant cytologic characteristics are clear in this tumor, and no false-negative results were obtained. But the absence of cribriform or papillary groups suggests an inconclusive diagnosis and sometimes the need to establish a differential diagnosis with other salivary tumors, and in particular with adenocarcinoma not otherwise specified (ADC-NOS) and high-grade mucoepidermoid carcinoma (h-g MEC). The pitfalls in the cytologic diagnosis of this tumor are discussed. In addition, the literature on the subject is reviewed. Diagn. Cytopathol. 1998;19:120–123. © 1998 Wiley-Liss, Inc.     

A case of oncocytic lipoadenoma of the submandibular gland and its diagnostic cytology challenges

Lipomatous tumors of the salivary gland in general are rare and oncocytic lipoadenomas are even much rarer. Most of the reported cases of oncocytic lipoadenoma were located in the parotid gland and to the best of our knowledge, only four cases reported to arise from the submandibular gland. The preoperative interpretation of the aspirates taken from these lesions can be difficult and challenging. We report a case of a 41 year old gentleman who presented with submandibular gland swelling. CT scan of the neck revealed an oval‐shape enhancing mass in the inferior aspect of the right submandibular gland measuring 19 × 12 mm. Fine needle aspiration biopsy (FNAB) showed hypocellular smears with few clusters of epithelial cells having oncocytic appearance. The cytologic findings were interpreted as “oncocytic lesion.” Submandibular gland excision was done. Histologically, a final diagnosis of oncocytic lipoadenoma was rendered. We present this rare entity to add to the few cases reported to date and to upsurge awareness during cytologic examination of oncocytic salivary gland lesions.     

Cytological features of mammary analogue secretory carcinoma of salivary gland: Fine‐needle aspiration of seven cases

Mammary analogue secretory carcinoma (MASC) is a recently described salivary gland neoplasm that is defined by ETV6‐NTRK3 gene fusion. There have been few case reports on the cytopathologic features of MASC to date. We examined the clinicopathological and cytological features of seven cases of MASC defined by RT‐PCR analysis of the ETV6‐NTRK3 fusion gene. The cases occurred in three men and four women aged between 39 and 68 years, with a mean of 51.6 years. In five of these seven cases, the tumor involved the parotid gland. Histologically, all cases displayed predominantly microcystic patterns, often a mixture of follicular and papillary‐cystic structures. All tumors were immunoreactive for mammaglobin, S‐100 protein, and vimentin. Available fine‐needle aspiration cytology smears were cellular and exhibited many loosely cohesive syncytial clusters or isolated cells. Many histiocytes, some of which contained hemosiderin pigments, and variously shaped mucinous material were evident in the background or within the epithelial clusters. The majority of cases showed small to medium‐sized follicular structures with secreted materials. Papillary clusters were occasionally found. Tumor cells exhibited small to medium‐sized round to oval nuclei, with a smooth contour and indistinct or small nucleoli, and vacuolated cytoplasm. No tumor cells had obvious intracytoplasmic zymogen granules. It appeared that clusters of small to medium‐sized follicular and papillary configurations consisting of bland tumor cells with vacuolated cytoplasm, but lack of intracytoplasmic zymogen granules, in a mucinous or hemosiderin‐laden histiocyte‐rich background, were a characteristic cytological feature highly suggestive of MASC. Diagn. Cytopathol. 2014;42:846–855. © 2014 Wiley Periodicals, Inc.