|Year : 2018 | Volume
| Issue : 2 | Page : 152-153
Canalicular adenoma: A rare case report
Swati Phore1, Rahul Singh2
1 Department of Oral Medicine and Radiology, Jind, Haryana, India
2 Department of Prosthodontics, Jind, Haryana, India
|Date of Web Publication||9-Apr-2018|
Department of Oral Medicine and Radiology, Jind, Haryana
Source of Support: None, Conflict of Interest: None
Canalicular adenomas (CAs) are uncommon benign salivary gland neoplasms of the oral cavity. They are typically located on the upper lip, buccal mucosa, and infrequently found on the palate and derived from minor salivary glands. Due to benign character of the tumor, CAs rarely present with bone erosion. Histologically, trabecular type of basal cell adenoma, pleomorphic adenoma, and polymorphous low-grade adenocarcinoma should be discriminated from CAs. A-36-year-old female patient with CA was presented. The lesion was managed surgically under local anesthesia, and 2 months follow-up was uneventful.
Keywords: Canalicular, labial, minor salivary
|How to cite this article:|
Phore S, Singh R. Canalicular adenoma: A rare case report. CHRISMED J Health Res 2018;5:152-3
| Introduction|| |
Salivary gland tumors are relatively uncommon and represent 2%–3% of head and neck neoplasms. Canalicular adenoma (CA) is a benign neoplasm that can manifest from minor salivary gland ductal tissue throughout the oral cavity and infrequently in the parotid gland. A high proportion of CAs occur in the upper lip (80%), a predilection not evident in other salivary gland tumors.
Some authors have reported rare cases in the palate (10%), parotid, esophagus, and mandible.
They are more commonly seen in females. The male-to-female ratio is 1:1.8.
It is a rare entity, representing <1% of salivary gland tumors. Previously, along with basal cell adenoma, CA was classified as a monomorphic adenoma. Originally, thought to be derived from terminal duct origin, there has been controversy about origin and separation from other salivary gland neoplasms. These tumors have undergone taxonomic drift, with many terms used to describe these tumors over the years. However, it is now agreed that CA is a unique salivary gland tumor, separated from other monomorphic adenomas in the last two editions of the World Health Organization (WHO). Many minor salivary gland tumors are frequently sampled by small or limited biopsies, and so the differential with other tumors can be challenging, resulting in incorrect classification, and inappropriate management.
Here, we present an unusual case of CA affecting the right upper lip.
| Case Report|| |
A 38-year-old female patient was admitted with a chief complaint of swelling in the upper lip since 1 year duration. The lesion was asymptomatic, and the patient's medical history was irrelevant. Patient consulted a dentist earlier who diagnosed the case as radicular cyst and did access opening of teeth with respect to 11, 12, and 13; however, there was no change in the size of the lesion. The patient was not on any medication now. At the extraoral examination, the patient presented facial asymmetry with swelling extending from the right side of the upper lip till base of the nose. Normal color of the skin was observed with no associated lymphadenopathy. The intraoral examination revealed soft swelling with bluish tinge in the right labial vestibule with respect to 11, 12, and 13 [Figure 1]. On palpation, submucous smooth and rubbery in consistency nodule were noted, located on the right side. Pain and bleeding were absent. Radiovisiograph was done with respect to 11, 12, and 13 and there was no abnormality detected [Figure 2]. Differential diagnosis included mucocele and the hypertrophic salivary gland. Obturation was done with respect to 11,12, and13; an excisional biopsy was performed under local anesthesia and sutures were placed. The material was submitted for histopathological analysis [Figure 3]. During the procedure, there was no difficulty in separating the lesion from the surrounding tissues.
|Figure 1: Intraoral swelling in labial vestibule extending from 11 to 13|
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Histopathological examination revealed a mucosal surface lined with stratified squamous epithelium. Deep to this were mixed labial salivary glands, predominantly mucous acini, which were partially surrounded by skeletal muscle and frequent nerve fibers. The main lesion was within the glandular tissue and was surrounded by smaller islands with similar histological characteristics. These lesions were composed of canalicular structures with a central lumen and were branching and anastomosing. These foci were covered by one or two layers of cuboidal to columnar epithelial cells with vesicular nuclei and inconspicuous nucleoli. No cytological pleomorphism or mitotic figures were observed. The tumor cells were arranged in a loose, otherwise paucicellular stroma with a prominent vascular pattern. 10 days after her first visit, the patient remained asymptomatic with no evidence of new lesions or recurrence. She was advised to return every month for follow-up appointments [Figure 4] due to the tumor's multifocal nature and potential for relapses.
| Discussion|| |
In 1953, Bauer and Bauer used the term CA, while Bhaskar and Weinmann were the first to use the term to describe this lesion. In 1970, Rauch et al. classified benign salivary gland neoplasms into two broad categories, monomorphic and pleomorphic adenoma. CA and basal cell adenoma were once considered to be a type of monomorphic adenoma. In 1972, WHO histological classification of salivary gland tumors classified them under other types of monomorphic adenoma.
Among the “monomorphic adenomas,” there are the following varieties; Warthins tumor, oncocytoma, or oxyphilic adenoma. In 1981, Batsakis and Brannon had given histological classification of monomorphic adenoma. (1) Tumors of terminal duct origin including basal cell adenoma and CA (2) Tumors of terminal or striated duct origin including sebaceous adenoma and sebaceous lymphadenoma. (3) Tumors of striated duct origin including oncocytoma and papillary cystadenoma lymphomatosum. (4) Tumors of excretory duct origin including sialadenoma papilliferum or inverted ductal papilloma. The basal cell adenoma and CA have relatively specific clinical and histopathological features, categorizing this tumor is ambiguous.
CA is a rare benign neoplasm arising mainly from minor salivary glands and rarely involving the major salivary glands. Clinically, CA usually presents as a well-demarcated, occasionally blue-tinged nodule measuring between 0.5 and 2 cm, which is otherwise asymptomatic. Prognosis is excellent, and recurrence is extremely rare even if just locally excised. The histological appearance of CA is uniform, with cells distributed in solid structures, trabeculae, tubules, and cribriform or membranous patterns, therefore, presenting a diagnostic challenge. There may be a fibrous capsule, and the presence of multiple adjacent foci is a relatively frequent finding microscopically.
The lesion tends to be solitary, but sometimes shows multiple tumors or confluent masses of variable sizes. Those features are not exclusive to CA, and thus, it can frequently be mistaken by other lesions, such as sialoliths or other benign salivary gland tumors. No hypothesis of the malignant lesion was suggested because of the bland appearance, circumscribed, mobile, and slow growth.
Enucleation, biopsy, and excision are the treatments proposed. However, with multifocal tumors and a periphery that is bosselated to nodular, a cure is best achieved by a surgical excision that has a small cuff of normal, uninvolved parenchyma. Follow-up of the patients is recommended, at least in the short term, to manage the possible multifocal disease.
Declaration of patient consent
The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient has given her consent for her images and other clinical information to be reported in the journal. The patient understand that names and initials will not be published and due efforts will be made to conceal identity, but anonymity cannot be guaranteed.
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Conflicts of interest
There are no conflicts of interest.
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[Figure 1], [Figure 2], [Figure 3], [Figure 4]