Canalicular adenoma of the palate: case report and literature review

Canalicular adenoma is a rare benign salivary gland tumor of the oral cavity, typically located in the upper lip and buccal mucosa and infrequently found on the palate. The tumor is usually confined to soft tissue and rarely presents with bone erosion. A case of a large and locally-aggressive palatal canalicular adenoma is presented. The lesion presented herein was an asymptomatic ulcerated mass with significant bone erosion. The tumor was managed surgically with excision and reconstruction of the resulting palatal defect with a full temporalis muscle flap.     

Canalicular adenoma: Not a basal cell adenoma

The evidence that canalicular adenomas and basal cell adenomas are separate entities is presented in this article. The clinical features were studied in a series of 13 previously unreported salivary gland tumors (5 canalicular adenomas and 8 basal cell adenomas) and 99 examples derived from the literature (68 canalicular adenomas and 31 basal cell adenomas). Representative tumors from the new cases and from 66 referred cases were studied by histologic, histochemical, and electron microscopic techniques. The two tumors differ significantly with respect to the age range of affected patients, site of predilection, and morphologic and histochemical features.     

Canalicular adenoma of the upper lip mimicking mucocele.

Salivary gland neoplasms are relatively rare. Among the salivary gland neoplasms minor salivary gland neoplasms are often deceptive to the clinician and challenging to the pathologist because of their varied morphology and diverse histopathological pattern. This article documents a case of canalicular adenoma of the upper lip mimicking mucocele and discusses the differential diagnosis of minor salivary gland neoplasms.     

Pleomorphic adenoma of the palate

Pleomorphic adenoma is the most common mixed benign tumor of major salivary glands. Approximately 80% of these tumors arise in the parotid gland, whereas 7% arise in the minor salivary glands. The most common sites for minor salivary gland where pleomorphic adenoma arises are the palates followed by lips and cheek. We report a palate mass in a 46-year-old male patient. The initial cytologic diagnosis by fine-needle aspiration biopsy was pleomorphic adenoma. This report describes a case of pleomorphic adenoma regarding all distinctive diagnoses with the review of the literature.     

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.     

Pleomorphic adenoma of the palate

An 82-year-old female with a history of high blood pressure and anorexia. She was referred for a long-evolving, asymptomatic large tumor (3x3 cm) on the right side of the palate (fig 1). The patient was wearing total dentures. Intraoral examination revealed a pediculate tumor of the same color as the adjacent mucosa and presenting a firm consistency. An MRI study (fig 2-3) and biopsy were carried out (fig 4-6).     

Pleomorphic adenoma of the soft palate

Pleomorphic adenoma is the commonest benign salivary gland tumour, accounting for almost three fourths of all such tumours. Pleomorphic adenoma most commonly occurs in the parotid gland; however it is also encountered in the submandibular, sublingual and minor salivary glands.     

Canalicular adenoma: report of five cases with ultrastructural observations

Canalicular adenomas from five patients were examined by light and electron microscopy. All patients were over 50 years of age; 4 of the lesions were from the upper lip, 4 were cystic, 2 showed capsular invasion and 1 was multifocal. Histopathologically there were epithelial duct-like or Canalicular structures cut at various angles and epithelial islands surrounded by hyalinized and mucinous connective tissue that contained little collagen. Ultrastructurally the epithelial islands contained many small lumina and connective tissue islands. The characteristic epithelial cell was columnar or cuboidal, extended from the lumina to the connective tissue, had almost straight lateral cell boundaries with desmosomes that predominated near the lumina, and possessed gap junctions and a small number of tight junctions. Their main cytoplasmic constituents were ribosomes, mitochondria, rough-surfaced endoplasmic reticulum and microfilaments. These findings show that canalicular adenomas are truly monomorphic and support the concept that they are derived from the cells of excretory ducts.     

Canalicular adenoma of the buccal mucosa. An ultrastructural and histochemical study

A canalicular adenoma that occurred in the minor salivary glands of the buccal mucosa in a 62-year-old black man was examined by electron microscopy and histochemistry. The ulcerated bowl-shaped tumor consisted mostly of ductlike tubules of columnar and cuboidal epithelial tumor cells which resembled intercalated duct cells ultrastructurally. Tumor cells resembling myoepithelial cells were not associated with these tubules. Less frequently, there were narrow tubules and cords adjacent to the capsule. Occasional cells in these cords contained variable amounts of microfilaments, often associated with focal densities, and thus resembled myoepithelial cells in varying stages of differentiation. Other noteworthy ultrastructural findings in this neoplasm included marked replication of the basal lamina of capillaries and the presence of a single, luminally oriented cilium in a tumor cell lining a tubule.     

Canalicular adenoma arising in the upper lip: review of the pathological findings

This case report describes a rare case of canalicular adenoma arising in the upper lip of a 61-year-old male patient. Macroscopic examination of the tumor revealed a well-defined, smooth, firm, elastic hard, round nodule with a diameter of 1.0 cm. The cut surface was white. Histopathology showed that the tumor was an encapsulated mass with a complex cellular pattern of anastomosing duct-like or trabecular structures lined by a single layer of tall columnar epithelial cells, which were embedded in a loose, fibrous, and highly vascular connective tissue stroma. The tumor cells were immunoreactive to AE1/AE3, CK19 and S-100, were partially positive for CK7, CK8, GFAP and PCNA, but were negative for SMA, CK13, CK14 and vimentin.     

Surgical management of pleomorphic adenoma of the palate

OBJECTIVES: The purpose of this article is to present an intraoral technique, which allows a wide local excision of pleomorphic adenoma of the palate with adequate mucosal and periosteal margins. STUDY DESIGN: Between September 1992 and May 1994 ten patients with pleomorphic adenoma of the palate were treated by one surgeon at the Oral and Maxillofacial Surgery Unit of the Jordan University of Science and Technology. A surgical technique, which was particularly useful for tumours extending into the soft palate, is described. RESULTS: Nine patients were aged between 15 and 25 years (mean age 20.1 years) and one patient was aged 50 years. Six of the patients were males. The tumour was removed from all ten patients by wide local excision with adequate margins, and after a follow-up period from 5 to 7 years (mean 6.3 years) there were no recurrences. CONCLUSION: This study has shown that wide local excision used for the treatment of pleomorphic adenoma of the palate is to be recommended. A close follow-up is necessary postoperatively.     

Epithelial-myoepithelial carcinoma arising in pleomorphic adenoma of the palate

A case of epithelial-myoepithelial carcinoma (EMC) in pleomorphic adenoma (PA) occurring in the palate of a 72-year-old woman is reported. The tumor was composed of 2 different components, PA and EMC, accounting for approximately 40% and 60% of the whole tumor, respectively. The EMC showed multiple tubular or solid nests, which were separated by a basement membrane and consisted of variable proportions of 2 cell types, cuboidal epithelial cells positive for cytokeratin and clear myoepithelial cells positive for glial fibrillary acid protein, whereas the myoepithelial nests of PA intermingled with hyaline and myxoid stroma. The malignancy was demonstrated by convincing evidence of invasion into the submucosa, although the EMC component was mostly surrounded by the PA components. An increased immunoreactivity of proliferating cell nuclear antigen in the EMC area in comparison to the PA area also suggested EMC arising in a PA.     

Canalicular adenoma presenting as an asymptomatic swelling of the upper lip: a case report

AIM: The purpose of this report is to present the clinical and histological features of a canalicular adenoma (CA) occurring in the upper lip and vestibular fornix of a 62-year-old woman. BACKGROUND: CA is an uncommon benign salivary gland tumor occurring almost exclusively in the intraoral glands. This tumor has often been referred to as a variant of the basal cell adenoma. However, the World Health Organization's latest histological classification of salivary gland tumors recognizes it as a separate entity under the broader heading of monomorphic adenoma, which is not related to any of the subtypes of basal cell adenomas. CASE REPORT: A 62-year-old woman with a chief complaint of an extraoral swelling in the upper lip. The evolution of the lesion was not known by the patient who recognized it when she touched her upper lip and found "an acne" on it. The patient wore complete dentures since age 17 and was not aware of any pain or tenderness in the area. Extra and intraoral examination revealed a mobile nodular lesion located in the right aspect of the upper lip near the nose and in the vestibular fornix between the lateral incisor and canine. Microscopic examination confirmed the final diagnosis of CA. The patient is currently free of disease 54 months after surgical excision of the tumor. SUMMARY: Local excision of symptomatic nodules seems to be sufficient to manage patients with multifocal CA.10 But, unlike other benign tumors, CA may need a longer follow-up due to its tendency towards multifocal occurrence and late recurrence.