A case of metastasizing pleomorphic adenoma

The pleomorphic adenoma is the most common benign salivary neoplasm. A case is presented in which a palatal pleomorphic adenoma seeded a metastasis in the medullary cavity of the anterior maxilla, apparently by hematogenous spread after surgical manipulation.     

Parotid pleomorphic adenoma with solitary renal metastasis

We present a rare case of renal metastasis of a recurrent pleomorphic adenoma of the parotid gland in an elderly woman. Metastasising pleomorphic adenoma shows malignant clinical behaviour, and although it appears histologically benign, there may be unknown molecular features that determine its unusual ability to spread.     

Metastasising pleomorphic adenoma of the parotid gland

A 33-year-old man had a left superficial parotidectomy for a pleomorphic adenoma. He remained well, but 28 years later developed a metastasis in a lymph node in the left supraclavicular fossa.     

Synchronous mucoepidermoid carcinoma of tongue and pleomorphic adenoma of submandibular gland

Presentation with synchronous salivary gland tumors is rare, with the most typical combination being Warthin's tumor and pleomorphic adenoma of the parotid gland. Involvement of minor salivary glands in such occurrences is extremely uncommon. We report a case of simultaneous mucoepidermoid carcinoma of the tongue and pleomorphic adenoma of the submandibular gland in a 40-year-old woman. The submandibular mass was initially considered to represent regional lymph node tumor metastasis but later was shown to be an intraglandular primary neoplasm.     

Metastatic benign pleomorphic adenoma. Report of a case and review of the literature

Pleomorphic adenoma (PA), originally called mixed tumour, is the most common neoplasm of the salivary glands and is generally accepted as benign biologically. Occasionally PA may give rise to metastasis. The metastasis may develop in a PA in which a malignant transformation occurs, either arising a carcinoma in the PA (carcinoma ex-mixed tumour) or as a carcinosarcoma (so-called true malignant mixed tumour). However, very rare benign PA eventually metastasise, usually after having a previous recurrence, displaying benign histological features as well in the primary tumour as in the metastasis. These tumours have been termed metastatic PA or metastatic mixed tumours. The aim of this paper is to report one case of metastatic histological benign pleomorphic adenoma, and to consider the clinical, pathological and therapeutic consequences of these rare tumours as well as its possible causes and mechanisms for its behaviour.     

Comparison of proliferating cell nuclear antigen index in benign and malignant salivary pleomorphic adenoma

The expression of proliferating cell nuclear antigen (PCNA) was studied in benign and malignant pleomorphic adenomas by using monoclonal antibody to PCNA. Carcinoma in pleomorphic adenoma (n=8), cell-rich variant (n=6) and typical pleomorphic adenoma (n=6) were selected in this study. The PCNA index in carcinoma in pleomorphic adenoma showed a higher index of nuclear staining (mean 22.9%, S.D. 6.2) than in typical pleomorphic adenoma (mean 6.9%, S.D. 3.4) or a cell-rich variant of pleomorphic adenoma (mean 8.8%, S.D. 3.3). A significant difference in PCNA index was found between benign and malignant pleomorphic adenoma (P<0.05). The present study suggests that PCNA index significantly differs between pleomorphic adenoma and carcinoma in pleomorphic adenoma, but in the prediction of malignant transformation potential it should be combined with routine histopathological examination.     

MMP-9和VEGF在腮腺多形性腺瘤中的表达研究

目的 研究MMP-9和VEGF在腮腺多形性腺瘤中的表达情况及其与肿瘤良恶性的关系。方法 应用荧光实时定量PCR和Western blotting方法检测32对多形性腺瘤及其瘤旁组织中MMP-9和VEGF的表达。结果 32例多形性腺瘤中26例为良性,6例为恶性。MMP-9和VEGF的mRNA和蛋白表达量在多形性腺瘤组织中高于瘤旁组织（P＜0.05）;在恶性多形性腺瘤组织中高于良性多形性腺瘤组织（P＜0.05）。结论 MMP-9和VEGF在腮腺多形性腺瘤中高表达,并且可能与腮腺多形性腺瘤的恶变相关;腮腺多形性腺瘤肿瘤外1 cm为安全切除界限。     

Are myoepithelial cells responsible for the widespread expression of inducible nitric oxide synthase in pleomorphic adenoma? An immunohistochemical study

Many of the actions of nitric oxide (NO) are still poorly understood. Recently, it has been shown that the inducible isoform of the enzyme nitric oxide synthase, iNOS, is expressed in both salivary ducts and pleomorphic adenoma. The current immunohistochemistry study determined whether or not this distribution correlated with smooth muscle actin (SMA) expression, thereby suggesting the expression by myoepithelial cells in both sites. Twenty cases of histologically confirmed pleomorphic adenoma, the sections of which contained adjacent normal salivary gland tissue, were stained for iNOS and smooth muscle actin (clone 1A4). The salivary ducts of all cases were stained intensely by both antibodies, with smooth muscle actin staining also being noted around acini in the normal gland parenchyma. Moderate or heavy staining for iNOS was found in all specimens of pleomorphic adenoma, with smooth muscle actin being distributed in a similar manner in 19 cases. Smooth muscle actin, but not iNOS, was also noted in blood vessels of both normal glands and tumours. The correlation between iNOS and SMA in pleomorphic adenoma was significant (P<0.001). The presence of iNOS in normal salivary ducts and pleomorphic adenoma is most likely due to expression by myoepithelial cells.     

Synchronous occurrence of ipsilateral synovial chondromatosis of the temporomandibular joint and pleomorphic adenoma of the parotid gland

We present a unique case characterized by true coexistence of synovial chondromatosis (SC) of the temporomandibular joint (TMJ) with a salivary gland tumor, specifically pleomorphic adenoma, of the ipsilateral parotid gland. The possibility that the condition was the result of a single pathologic entity, ie, SC with extracapsular involvement or pleomorphic adenoma affecting the TMJ, received strong consideration. Nonetheless, careful assessment of the clinical, radiographic, MRI, and surgical findings strongly suggested the synchronous occurrence of 2 separate pathologic processes, despite their close proximity. Further, histopathologic examination confirmed the presence of both SC of the TMJ and pleomorphic adenoma of the superficial lobe of the ipsilateral parotid gland. Previous reports have pointed out the possibility of misdiagnosing extracapsular spread of SC as a salivary gland tumor. Vice versa, it has been noted that parotid gland tumors, especially malignant, may cause TMJ symptoms similar to those of SC. However, to the best of our knowledge, this is the first time that true synchronous occurrence of ipsilateral SC and pleomorphic adenoma, or parotid tumor of any kind, is reported.     

Pleomorphic adenoma of the palate

Pleomorphic adenoma, is the most common tumor (50%) of the major and minor salivary glands. Seventy percent of the tumors of the minor salivary glands are pleomorphic adenomas, and the most common intraoral site is the palate, followed by the upper lip and buccal mucosa. Pleomorphic adenoma appears as a painless firm mass and, in most cases, does not cause ulceration of the overlying mucosa. Generally it is mobile, except when it occurs in the hard palate. Intraoral mixed tumors, especially those noted within the palate, lack a well-defined capsule. Lesions of the palate frequently involve periosteum or bone. Approximately 25% of benign mixed tumors undergo malignant transformation. Treatment for the pleomorphic adenoma is radical surgery. Inadequate resection leads to local recurrence. The authors report a palate pleomorphic adenoma in a 67-year-old female patient.     

血管内皮生长因子和微血管密度在唾液腺腺样囊性癌中的表达

目的探讨血管内皮生长因子（VEGF）和微血管密度（MVD）在腺样囊性癌（ACC）中表达的相关性及两者与腺样囊性癌的临床病理类型的关系。方法应用免疫组织化学方法．检测35例唾液腺腺样囊性癌、13例多形性腺瘤和10例正常唾液腺组织中VEGF的表达和微血管密度与形态。结果VEGF的阳性表达率和MVD计数在正常唾液腺组织、多形性腺瘤、ACC中依次增加,组间差异具有统计学意义（P〈0．05）;ACC中MVD计数随着VEGF表达的增强而升高（P〈0．05）;ACC中VEGF的阳性表达率和MVD计数依次增加．转移组高于非转移组．神经侵犯组高于非侵犯组（JD〈0．05）;微血管形态在正常唾液腺组织、多形性腺瘤以窦状扩张型为主,ACC中多表现为芽状和细索状及球状血管丛。结论VEGF的表达和微血管密度形态与ACC的临床类型密切相关。     

谷胱甘肽过氧化物酶-3在腮腺多形性腺瘤中的表达及意义

目的 :研究谷胱甘肽过氧化物酶-3(glutathione peroxidase-3,GPX-3)基因及蛋白在腮腺良、恶性多形性腺瘤中的表达,以明确GPX-3与腮腺多形性腺瘤发生、发展的相关性,为临床预测腮腺多形性腺瘤的发生及恶变提供理论依据。方法:采用荧光定量PCR和蛋白免疫印迹法检测30例腮腺多形性腺瘤,30例腮腺多形性腺瘤的瘤旁2 cm腺体组织,以及10例恶性腮腺多形性腺瘤中的GPX-3 mRNA及蛋白的表达,对其相对表达量进行统计学分析。结果:GPX-3 mRNA和蛋白在腮腺良、恶性多形性腺瘤中的表达明显低于瘤旁腺体组织,且在腮腺恶性多形性腺瘤中的表达最低,差异有统计学意义(P<0.01)。GPX-3在腮腺多形性腺瘤中的表达与患者的年龄、性别及肿瘤大小无关,差异无统计学意义(P>0.05),且GPX-3在腮腺多形性腺瘤中的表达与肿瘤TNM分期及恶性成分比例有关,其差异有统计学意义(P<0.05)。结论:GPX-3在腮腺良性多形性腺瘤中低表达,且在腮腺恶性多形性腺瘤中的表达最低,提示GPX-3的低表达与腮腺多形性腺瘤的发生及恶变密切相关。     

颌下腺转移性多形性腺瘤1例

本文报道1例罕见的转移性多形性腺瘤,患者女性,30岁,左颌下腺及右锁骨上包块术后病检结果与患者8年前左颌下腺肿块切除后病检结果一致,病理形态均表现为良性多形性腺瘤。并结合文献报道,对转移性多形性腺瘤的临床病理特征、发病机制及防治方法等进行讨论。     

基质金属蛋白酶及其组织抑制剂在涎腺多形性腺瘤生物学行为中的意义

目的 研究涎腺多形性腺瘤中基质金属蛋白酶(MMP)-2、9及其组织抑制剂(TIMP)-1、2的表达变化与其生物学行为的关系。方法 用免疫组化SP法和明胶酶谱法分别检测9例普通型和14例生长活跃型多形性腺瘤中MMP-2、9及TIMP-1、2的阳性表达及细胞定位，分析其中酶原与活性酶的含量比例。结果 MMP-2及MMP-2／TIMP-1、MMP-2／TIMP-2的比值在生长活跃型多形性腺瘤中的表达高于普通型，活性MMP-2、MMP-9酶原和活性酶在生长活跃型多形性腺瘤中的表达明显高于普通型，涎腺良性肿瘤与普通型多形性腺瘤间、涎腺恶性肿瘤与生长活跃型多形性腺瘤间差异无统计学意义。结论 涎腺生长活跃型多形性腺瘤与涎腺恶性肿瘤有相似的MMP-2、9和TIMP-1、2表达特征，而普通型多形性腺瘤中MMP-2、9和TIMP-1、2的表达与涎腺良性肿瘤相近。检测MMPs、TIMPs有助于判断涎腺多形性腺瘤的生物学行为。     

Mucoepidermoid carcinoma arising from pleomorphic adenoma of the soft palate

Carcinoma arising in pleomorphic adenoma is a rare entity. A case of mucoepidermoid carcinoma in pleomorphic adenoma occurring in the soft palate of a 40-year-old woman is reported. An intraoral excision of the tumor was performed. Histopathological examination revealed high-grade mucoepidermoid carcinoma proliferated in pleomorphic adenoma with free surgical margin. The patient received adjuvant neck radiotherapy. She remains free of disease 16 months post-treatment.     

Current thinking about the management of recurrent pleomorphic adenoma of the parotid: a structured review

Pleomorphic adenoma is the most common tumour of the parotid gland, and can recur after excision. Recurrent pleomorphic adenoma can be a challenge to treat, and has variable outcomes. The aim of this review was to summarise current thinking in its management, which may be helpful to clinical teams and could improve patients’ health-related quality of life. We searched several online databases using the key terms pleomorphic adenoma, recurrent pleomorphic adenoma, parotid gland tumours, parotid surgery, radiotherapy and parotid pleomorphic adenoma, and parotid surgery outcomes. Information collected included sample size, recurrence rate, condition of the facial nerve, type of operation, adjuvant treatments associated with recurrence, and clinical outcome. We screened 2301 papers, of which 49 were eligible. There was no consensus among authors about management. There are few if any randomised studies, and so conclusions in most papers were based on coherent arguments. Pleomorphic adenomas of the parotid tend to recur after long intervals, with a propensity towards multifocal disease, and the risk of recurrence (which depends on the initial surgical technique) is higher when the initial operation was done at a young age, after enucleation, and if the initial margins were invaded. Published conclusions suggest that the accepted management varies from observation in selected cases to total parotidectomy with or without postoperative radiotherapy.     

83例涎腺恶性多形性腺瘤临床病理分析

作者总结分析８３例恶性多形性腺瘤的临床病理特点。患者平均年龄５３岁，男女之比为１．２：１，肿瘤部位依次为腮腺４７．９％，颌下腺２４％、腭部２０％，肿瘤中恶性成份为癌型７６例，癌肉瘤７例。明显影响预后的因素有（１）肿瘤部位；（２）组织学亚型，（３）肿瘤分化程度，（４）浸润状况，（５）淋巴结有无转移。患者５年生存率为５２．７％，恶性程度明显高地其它常见型涎腺癌。作者认为多形性腺瘤是它的癌前病变，早期切     

Pleomorphic adenoma with nuclear palisading arrangement of modified myoepithelial cells: histopathologic and immunohistochemical study.

Pleomorphic adenomas with a nuclear palisading arrangement of spindle-shaped modified myoepithelial cells (MMCs), suggesting the appearance of palisading leiomyoma or Antoni's A type of neurilemmoma, are quite rare, and its cytologic nature has been poorly understood. This paper reports histologic and immunohistochemical findings of palisading MMCs in two cases of pleomorphic adenoma. Histologically, foci of spindle-shaped MMCs with nuclei in a palisading arrangement were scattered in the myxoid areas. Near the large foci of spindle-shaped MMCs with nuclear palisading arrangements, tiny foci of spindle-shaped MMCs forming nuclear palisading or rosette-like arrangements were seen. Such nuclear palisading arrangements of MMCs were suggestive of differentiation or transformation of MMCs into cells that were more smooth muscle in nature, supported by occasional existence of palisading leiomyoma in the myometrium and gastrointestinal tract. However, immunohistochemical findings of palisading MMCs in pleomorphic adenoma were similar to those of non-palisading MMCs, and showed no evidence of smooth muscle differentiation; neither palisading nor non-palisading MMCs in pleomorphic adenoma expressed desmin, muscle specific actin (HHF-35), alpha smooth muscle actin, or myoglobin. The biologic significance and formative mechanism of nuclear palisading arrangement of MMCs in pleomorphic adenoma could not be determined in the present study. However, if the MMCs with nuclear palisading arrangements in pleomorphic adenoma, presented here, are aspirated for cytologic diagnosis or are included in a small biopsy specimen, the correct diagnosis of pleomorphic adenoma may be confused by a suspicion of myogenic or neurogenic tumor.     

A ciliated cyst as a component of pleomorphic adenoma of the parotid gland

A large cyst, lined with ciliated cells (ciliated cyst), was found as a component of a pleomorphic adenoma of the left parotid gland in a 34-year-old Japanese man. The dimensions of the tumor were 25 × 33 mm and it consisted of a solid mass with a centrally located cyst 20 × 23 mm. which contained yellowish-brown material of muddy consistency. The tumor was encapsulated and the solid mass had features typical of a pleomorphic adenoma. The inner surface of the cyst was lined with ciliated cells and scattered mucus-secreting cells in addition to cuboidal-to-flattened cells. In some regions, the neoplastic cells of the pleomorphic adenoma were exposed to the cavity of the cyst. A histological transformation from ciliated cells to pleomorphic adenomatous cells was also observed. These findings indicated that the ciliated epithelium was an element of the tumor. This is the first report, to our knowledge, of a ciliated cyst derived from some elements of a pleomorphic adenoma of the salivary gland.     

Is extracapsular dissection for pleomorphic adenoma rather a euphemism for enucleation that jeopardises the intactness of the capsule?

The aim of this study was to compare several surgical modalities with respect to the incidence of positive margins and focal capsular exposure of pleomorphic adenoma of the parotid gland. The clinical records and histopathological findings of all patients who underwent parotidectomy for pleomorphic adenoma between 2006 and 2020 were retrospectively evaluated (n = 845). The lesion was removed by extracapsular dissection in 577 cases (68%) and facial nerve dissection in 268 (32%). Our analysis did not reveal a statistically significant difference between the examined modalities regarding positive margins (p=0.648) or capsular exposure (p=0.112). Recurrences were detected in 7/845 cases (0.82%) with a mean (range) follow-up time of 82.3 (6-183) months. The choice of surgical method does not seem to have a significant effect on the incidence of positive margins, or on the capsular exposure of a pleomorphic adenoma.