Malignant myoepithelioma arising from recurrent pleomorphic adenoma of minor salivary gland.

Malignant myoepitheliomas of the salivary gland are very rare tumors which may either arise de novo or develop in a pre-existing pleomorphic adenoma. We report a case of malignant myoepithelioma of the minor salivary gland that progressed from benign pleomorphic adenoma. The original pleomorphic adenoma was resected in 1979 (the '79 tumor). The first recurrent tumor was operated in 1995 (the '95 tumor). The '95 tumor was diagnosed as pleomorphic adenoma. Although the myoepithelial tumor component was more prevalent in the '95 tumor, histological features of the first recurrent tumor were similar to the '79 tumor. The second recurrent tumor showed more aggressive clinical features (the '98 tumor). It also showed massive growth of myoepithelial tumor cells with bone invasion, which led to the diagnosis of the '98 tumor as malignant myoepithelioma. With adequate surgical margin, the patient has been free from tumor recurrence for 20 months.     

Malignant myoepithelioma of the soft palate

Malignant myoepitheliomas (MM) (myoepithelial carcinomas) are rare tumors representing <1% of salivary gland tumors. They are characterized as being locally aggressive. Rarely do they present distant metastases; however, when they do metastasize the sites most affected are the lungs, liver, pleura, peritoneum and skin. They may originate de novo in a pleomorphic adenoma or a benign myoepithelioma. We report the case of a patient with a submucosal lesion of the soft palate measuring ∼4 cm × 3 cm. The patient underwent transoral resection with a microscope and CO₂ laser. Histopathological report was MM originating in a pleomorphic adenoma. Management of this neoplasm is controversial. Myoepithelial carcinoma is a rare neoplasm whose diagnosis includes immunohistochemical (IHC) studies. Surgery is the cornerstone of treatment. Management with laser surgery may preserve the function of the soft palate without deterioration of the quality of life in these patients.     

Myoepithelial neoplasia of the submandibular gland: case report and therapeutic considerations

Tumors of the submandibular gland typically arise from the seromucinous acini, which make up the majority of the gland. The most common benign tumor of this structure is the pleomorphic adenoma, whereas the most common malignancy of the submandibular gland is adenoid cystic carcinoma. We describe an unusual case of a neoplastic process of the myoepithelial cells of the submandibular gland in a middle-aged woman. This rare tumor is most commonly diagnosed in the parotid gland and in the minor salivary glands of the hard palate; a review of the literature uncovered only 5 previous reports of myoepithelioma of the submandibular gland. Distinguishing myoepithelioma from benign pleomorphic adenoma and malignant myoepithelial carcinomas can be challenging. Immunohistochemical staining can help to distinguish between the benign neoplasms, but histologic features remain the "gold standard" for diagnosing the malignant tumors. Increasing use of immunohistochemistry panels to assess parotid neoplasms also suggests that myoepithelioma may be underrecognized.     

A case of myoepithelioma of the nasal cavity

Myoepithelioma is a rare tumor, most frequently located in the salivary gland. Case reports of extra-salivary myoepithelioma are sporadic, with only one case in the nasal cavity. A 68-year-old male patient presented with a myoepithelioma of the nasal cavity manifesting as nasal obstruction and epistaxis, which was treated successfully with endoscopic excision. Histological examination revealed myoepithelial cells and myxoid stroma, which confirmed the diagnosis of myoepithelioma. The behavioral pattern is similar to if not identical with that of the mixed tumor, pleomorphic adenoma, which is benign, but the potential for recurrence is always present, especially if complete resection is not achieved.     

Benign pleomorphic adenoma of the soft palate metastasizing to the sphenoid sinus

A benign pleomorphic adenoma is the most common tumor of the salivary glands. This tumor has the potential to metastasize to bone, the head and neck region, visceral organs and skin. Although there a few reports about a benign pleomorphic adenoma metastasizing to the maxillary sinus in the paranasal sinuses, there are no reports about a metastatic benign pleomorphic adenoma in the sphenoid sinus. We report here on a case of a benign pleomorphic adenoma of the soft palate that metastasized to the sphenoid sinus, and we briefly review the relevant clinical literature.     

Mucoepidermoid carcinoma of the hard palate

A case of mucoepidermoid carcinoma originating in the hard palate was presented. Histological diagnosis of the removed mass at the first operation was pleomorphic adenoma. Tumor recurred at the same site three years later. Subtotal maxillectomy was performed and recurrent tumor was histologically diagnosed as low grade malignant mucoepidermoid carcinoma. A two-year follow-up showed no evidence of recurrence. The low grade malignant mucoepidermoid carcinoma strongly resembles pleomorphic adenoma. The differential diagnosis is important for the better treatment and prognosis.     

Approach to benign tumors of the palate: analysis of 28 cases

We conducted a retrospective analysis of 28 patients-15 men and 13 women, aged 17 to 71 years (mean: 41.6)-who had undergone surgery for the treatment of a benign tumor of the hard or soft palate. The most common chief complaint was a palatal mass, which was reported by 14 patients (50.0%). Tumors were more common in the hard palate than in the soft palate by a margin of 23 to 5 (82.1 to 17.9%; p = 0.001). The most common histopathologic diagnosis was pleomorphic adenoma, which occurred in 9 cases (32.1%). Most patients were treated with local excision with clear margins, which was sufficient in almost all cases, as there were only 2 recurrences, both of which occurred in men with a hard-palate pleomorphic adenoma. For these 2 patients, a wider excision and repair with palatal islet flaps was performed, and no further recurrence or malignant transformation was observed during follow-up. Two patients with a soft-palate hemangioma were treated with an intralesional steroid injection and radiofrequency ablation, which reduced the size of their lesion considerably.     

The synchroneous tumors of different histopathology in the parotid salivary gland

Ipsilateral salivary gland tumors of different histological types are very rare. Out of 196 parotidectomies performed (from 03. 2001 to 12. 2005), in 6 (3.06%) cases synchronous tumors of different type has been found in pathologic specimens. In 5 cases pleomorphic adenoma was one of synchronous tumor--in 2 cases with adenocarcinoma and in single cases with salivary duct carcinoma, adenolymphoma, and myoepithelioma. In one case, the adenolymphoma was synchronous with carcinoma planoepitheliale metastaticum from the primary in the skin post auricular area (late metastasis). Following the review of literature concerning the problem, two concepts has been critically discussed--the real synchronous occurrence of two different tumors, and transformation of benign tumor of salivary neoplasm to its malignant form.     

Carcinosarcoma arising from a preexisting pleomorphic adenoma--true malignant mixed tumor of the parotid gland

Carcinosarcoma (true malignant mixed tumor) is rare in salivary gland neoplasms. Even rarer is a carcinosarcoma arising from a preexisting pleomorphic adenoma. Case: a 49-year-old woman was admitted with left neck pain. Computed tomography and USG-examination revealed a mass originating from left parotid gland. The patient undergone total parotidectomy with facial nerve preservation and then irradiation and chemioteraphy. Clinical and histologic date revealed it had developed from a preexisting pleomorphic adenoma. Conclusion: microscopic examination showed and neoplasm comprised of sarcomatous and carcinomatous cells. This tumor seemed to consist of two histogenetically different populations of cells. We also review the literature and dicuss the histogenetic origin of the carcinosarcoma of salivary gland.     

Giant myoepithelioma of the upper lip

Myoepithelioma is a relatively rare form of salivary gland tumor composed entirely of myoepithelial cells. This tumor was formerly considered to be a subtype of pleomorphic adenoma; however, in the latest World Health Organization classification of 1991 it is listed as an independent entity. We report herein an extremely rare case of myoepithelioma of the upper lip. A 78-year-old Japanese female presented with a huge, painless mass on her upper lip. CT and MRI revealed a 50 x 40 mm(2) well-defined ovoid tumor. A benign minor salivary gland tumor was clinically suspected, and the patient underwent complete resection of the tumor under general anesthesia. The surgical defect was immediately reconstructed using an Abbe-Estlander flap. The tumor was histopathologically diagnosed as a benign myoepithelioma of the minor salivary gland. Immunohistochemically, the tumor cells were positive for vimentin, cytokeratins, alpha-smooth muscle actin and S-100 protein, confirming the morphological diagnosis of myoepithelioma. The patient's postoperative clinical course was uneventful, and satisfactory results were obtained both functionally and esthetically. The pathology, clinical manifestations and treatment of myoepithelioma are reviewed.     

Polymorphous low-grade adenocarcinoma: a palatine and a labial location

INTRODUCTION: Polymorphous low-grade adenocarcinoma (PLGA) is a variant of malignant tumor of minor salivary glands. We had for aim to discuss morphology, evolution and differential diagnosis of this rare tumor. CASE REPORTS: The first case was a 65-year-old woman admitted for a two-month history of a right submaxillary swelling. The examination revealed a tumor of the right side of the palate. Biopsy was positive for a pleomorphic adenoma. The mass was enlarged and surgical resection was performed. The diagnosis was a partially resected PLGA. The patient also received adjuvant radiotherapy. There was a local recurrence 28 months after complete treatment. The second case was a 57-year-old woman who consulted for a 12-year history of lower lip swelling. The examination revealed a painless 2cm long located nodule in the mucosal side of the lower lip. An excisional biopsy was performed. The pathological examination concluded to a completely resected PLGA. The patient was free of disease at 54 months follow-up. DISCUSSION: The morphologic diversity and cytological uniformity of PLGA may make the differential diagnostic difficult especially with adenoid cystic carcinoma and pleomorphic adenoma. Its aggressiveness is proved by a local infiltrative growth pattern requiring a large surgical excision.     

Giant myoepithelioma of the upper lip

Myoepithelioma is a relatively rare form of salivary gland tumor composed entirely of myoepithelial cells. This tumor was formerly considered to be a subtype of pleomorphic adenoma; however, in the latest World Health Organization classification of 1991 it is listed as an independent entity. We report herein an extremely rare case of myoepithelioma of the upper lip. A 78-year-old Japanese female presented with a huge, painless mass on her upper lip. CT and MRI revealed a 50×40 mm² well-defined ovoid tumor. A benign minor salivary gland tumor was clinically suspected, and the patient underwent complete resection of the tumor under general anesthesia. The surgical defect was immediately reconstructed using an Abbe–Estlander flap. The tumor was histopathologically diagnosed as a benign myoepithelioma of the minor salivary gland. Immunohistochemically, the tumor cells were positive for vimentin, cytokeratins, α-smooth muscle actin and S-100 protein, confirming the morphological diagnosis of myoepithelioma. The patient's postoperative clinical course was uneventful, and satisfactory results were obtained both functionally and esthetically. The pathology, clinical manifestations and treatment of myoepithelioma are reviewed.     

Endoscopic surgery for Warthin's tumor of the nasopharynx

Warthin's tumor almost exclusively occurs in the parotid gland. It is the second most common tumor after the pleomorphic adenoma. The extraparotid or ectopic Warthin's tumor is rare and is normally situated in the submandibular gland, cervical lymph node, lip, cheek, tongue, hard palate, lacrimal gland and larynx. In this paper we present a case of the Warthin's tumor with ectopic localization in the nasopharynx with asymptomatic outcome. A 56-year-old man has been diagnosed for 10-year history of headache. He had no past history of any otolaryngologic disease. The axial and coronal NMR scans showed a round-shaped, cyst-like tumor of approximately 12 mm in diameter. The tumor was in the middle line of the nasopharynx without compression of the Eustachian tubes. The histopathologic diagnosis was consisted with Warthin's tumor. The patient underwent tumor removal using an endoscopic transnasal approach. The Warthin's tumor is a benign lesion with extremely rare occurrence in the nasopharynx. The symptoms are varied and sometimes it could be recognized accidentally. In a very rare cases it may transform to malignant neoplasm. The optional approach to the nasopharynx must be selected after careful consideration of the individual case. An endoscopic power instrumentation surgery are recommended for small lesions.     

Parapharyngeal space lesions: with a reference to biopsy

We received seven cases of parapharyngeal space lesions and discussed on necessity of biopsy. Tumors originating in the parapharyngeal space were represented by parotid pleomorphic adenomas which showed bulging of soft palate and tonsillar fossa, and benign neurogenic tumors which showed bulging of the lateral wall of the meso-pharynx. In these cases, preoperative biopsy was not necessary unless the lesion was suspected, of malignancy by CT, MRI and so on. In the case of bulging of soft palate and tonsillar fossa, if CT or MRI finding shows that the tumor is localized in the median portion of the parapharyngeal space and is separated from greater vessels and nerves existing in the parapharyngeal space, therapeutic protocol might be planned after an establishment of histological diagnosis with biopsy. In the case of a bulging lateral wall of the meso-pharynx with a history of malignant neoplasm of the head and neck, lymph node metastasis should be thought about.     

Primary pleomorphic adenoma of the external ear canal. Report of a case and literature review

INTRODUCTION: Primary neoplasms of the external ear canal are rare, and 5% of these tumors are of glandular origin. Ceruminal glands are modified sweat glands of the skin of the external auditory meatus that may give rise to (a) benign tumors such as ceruminous adenoma, pleomorphic adenoma, and syringocystadenoma papilliferum, and (b) malignant tumors such as ceruminous adenocarcinoma, adenoid cystic carcinoma, and mucoepidermoid carcinoma. An alternative theory holds that pleomorphic adenomas may well arise from ectopic salivary tissue present in the external ear canal. These tumors are very rare and usually have a benign course. In this report, we describe an unusual case of pleomorphic adenoma of the external auditory canal associated with chronic infection of the middle ear. CASE REPORT: A 60-year-old woman presented with exacerbation of left otalgia over a 6-month period. She had been affected with chronic otitis media and aural polyps for the last 13 years, for which she had received medical treatment only. A canal-filling aural polyp was noted on clinical examination. Subsequent biopsy and histologic examination revealed pleomorphic adenoma of the external ear canal, possibly with malignant elements. Magnetic resonance imaging showed no intracranial extension or any association with the adjacent parotid gland. The patient underwent modified radical mastoidectomy and complete resection of the tumor and the entire skin of the external auditory canal. Final histology and immunohistochemistry confirmed the absence of malignancy, and no recurrence has been reported 1 year postoperatively. CONCLUSIONS: Pleomorphic adenoma is an extremely rare tumor arising from the ceruminal glands of the external ear canal. Nonspecific presentation and difficult histologic diagnosis characterize this benign neoplasm. Wide local excision is the mainstay of treatment.     

Carcinomas ex pleomorphic adenoma and malignant mixed tumors. Histomorphologic indexes

Clinical and pathologic differences exist between the several neoplasms encompassed by the term malignant mixed tumors of salivary glands. The majority of the neoplasms are carcinomas ex pleomorphic adenoma. True malignant mixed tumors (carcinosarcomas) are rare, and even more rare are the benign metastasizing mixed tumors. This study of 40 malignant mixed tumors indicates that two previously unreported variables, measured invasion in millimeters and histologic subclassifications of the malignant neoplasm, are valuable guides to prognosis and biologic behavior. All patients whose malignant neoplasm extended for more than 8 mm beyond residual capsule or benign residual tumor died of their disease. The extent of invasion also correlated with perineurial invasion, involvement of bone, and metastases to lymph nodes. Histologic subclassification points out that there is no prototypical carcinoma ex pleomorphic adenoma and that high- and low-grade carcinomas can be found. Only one of the patients with low-grade (terminal duct) carcinomas died of his disease during follow-up periods extending to over 20 years.     

Carcinoma ex pleomorphic adenoma of the palatal minor salivary gland with extension into the nasopharynx

Carcinoma ex pleomorphic adenoma presenting in the nasopharynx is extremely rare. We present a case of carcinoma ex pleomorphic adenoma occupying the nasopharynx and the soft palate in a 51-year-old woman. To the best of our knowledge, this is the first reported case of carcinoma ex pleomorphic adenoma in the nasopharynx.     

妊娠期鼻咽恶性肿瘤临床分析

目的 总结妊娠期合并鼻咽恶性肿瘤患者的临床资料,探讨妊娠期合并鼻咽恶性肿瘤的临床特点,以达到早期诊断、早期治疗的目的。方法 以2007年9月至2012年7月收治的妊娠期合并鼻咽恶性肿瘤5例作为研究对象。其中鼻咽鳞状细胞癌4例,鼻咽恶性肌上皮瘤1例。回顾分析患者的临床表现、诊断结果及治疗情况,并对患者及其子代进行随访。结果 5例患者均为单胎妊娠,3例(60.00%)在妊娠过程中活检确诊后终止妊娠行引产术,2例(40.00%)为妊娠中发病,分别于产后1周和产后1个月活检确诊。新生儿健康存活。鼻咽鳞状细胞癌患者均采用同期放化疗,鼻咽恶性肌上皮瘤患者采用经鼻内镜及软腭联合径路手术治疗,术后1周辅助放疗。结论 妊娠期合并鼻咽恶性肿瘤较为少见,合并鼻咽恶性肌上皮瘤更为罕见。妊娠期由于检查及用药的局限性,容易出现漏诊及误诊。治疗应根据肿瘤性质、分期、患者意愿等因素综合考虑,并对患者及子代做长期随访。     

Extra-major salivary gland pleomorphic adenoma of the head and neck: a 10-year experience and review of the literature

Pleomorphic adenomas, or benign mixed tumors, make up 65% of all salivary gland tumors. They also can be found as solid tumors in other parts of the head and neck region, such as the auditory canal, the eyelids, and the orbital area. In this study, we investigated extra-major salivary gland pleomorphic adenomas of the head and neck region retrospectively at a tertiary care center. Between March 1998 and June 2009, 37 patients underwent primary surgery for extra-major salivary gland pleomorphic adenoma of the head and neck. The duration of symptoms, radiographic findings, operative procedures, and pathologic findings were documented. Of the 37 patients enrolled, 22 were male and 15 were female, with a median age of 57?years. Tumors were found in the soft palate, hard palate, nasopharynx, orbital area, trachea, buccal mucosa, cheek, nasal septum, upper lip, lower eyelid, and external auditory canal. Cellular variant of the pleomorphic adenoma was found in four patients, while the remaining patients presented with the classic variant. No myxoid subgroup was noted in our study. Carcinoma ex pleomorphic adenoma was observed only in one patient for whom radical surgery was performed. Twenty-eight patients (76%) had long-term follow-ups, with the average follow-up period being 4.5?years. Local recurrence was observed in three patients, and they underwent revision surgery during the follow-up period. Our results indicate that extra-major salivary gland pleomorphic adenomas are most commonly found in the soft palate. Wide excision was the treatment of choice, although its efficacy might be compromised with cosmetics and functional structures of the head and neck. Therefore, long-term follow-up of patients is necessary.     

Pleomorphic adenoma in nasal cavity: immunohistochemical study of three cases

Intranasal pleomorphic adenoma is a rare neoplasm, and thus only one case report addressed immunohistochemical findings of this neoplasm. To define immunohistochemical features of intranasal pleomorphic adenoma, we studied three cases of the pleomorphic adenoma developed from the nasal septum. Subsequently, immunohistochemical reactivities of the tumor cells for various cytokeratins, glial fibrillary acidic protein (GFAP), S100 protein, alpha-smooth muscle actin (SMA), and vimentin were similar to those of pleomorphic adenoma of the parotid gland. The tumors examined in this study had different histological components, such as predominance of myxoid area, solid area, or tubuloductal structure, but immunoreactivity of both epithelial and myoepithelial tumor cells were the same in the tumors. Therefore, immunoreactivity of the tumor cells were the same among the intranasal pleomorphic adenoma having various histological components.