Pleomorphic Adenoma of the Upper Lip: A Case Report

Pleomorphic adenoma (mixed tumor) of the upper lip: A case report

BACKGROUND

Salivary gland tumors are relatively rare. Most minor salivary gland tumors are malignant with benign tumors accounting for 18% of the tumors. Pleomorphic adenoma (PA) is the most common salivary gland tumor. Lip PA is uncommon with 9.8% occurring in the upper lip. We are adding on the knowledge of the rare upper lip PA (benign mixed tumor).

CASE SUMMARY

We report an upper lip PA (benign mixed tumor) in a 28-year-old man. His complaint was a painless swelling on the upper lip. A painless, non-tender, well-circumscribed, slightly mobile, sessile, nodular, and rubbery (in consistency) tumor measuring 5.0 cm x 2.0 cm was noted on the left side of his upper lip. The overlying skin was not fixed and of normal color. There was no ulceration, and palpation did not elicit pain or bleeding. There was no history of trauma. Blunt dissection was used to completely excise the nodular, whitish, and encapsulated tumor. Microscopy showed a well-circumscribed and partly encapsulated biphasic lesion, with large lobules of myxo-chondroid stroma and intervening cellular nodules of basaloid cells, well-formed tubules containing eosinic secretion, and nests of myoepithelial cells. A diagnosis of PA (benign mixed tumor) was confirmed.

CONCLUSION

Blunt dissection is indicated to preserve the cosmesis and function of the upper lip.

Clinicopathological characteristics of pleomorphic adenoma from the labial gland: A 20-year experience with 173 cases in one single institution

OBJECTIVE

Pleomorphic adenoma (PA) of the lip is not a common phenomenon, and existing literature provides limited information on the clinicopathological features of labial PA.

STUDY DESIGN

Patients diagnosed with labial PA at our single institution over the past 20 years (2001-2020) was retrospectively screened and analyzed to investigate the epidemiologic and clinicopathological features of these tumors.

RESULTS

A total of 173 cases were screened out, and the average age was 44.3 (range 7-82) years, with a peak incidence rate during the third decade. A slight predilection for men (52%) was observed, and PA occurs more frequently in the upper lip than in the lower lip, with a ratio of 14.7:1. On clinical examination, labial PAs usually present as painless masses that develop slowly with no systemic symptoms. Histologically, labial PAs contain myoepithelial and polygonal epithelial cells in myxoid, hyaline, fibrous, chondroid, and even osseous tissues, similar to those in other sites. Specifically, 15 of 173 patients with labial PA presented with cutaneous PA.

CONCLUSION

Labial PA presents over a wide age range and dominantly occurs at the upper lip. Surgical resection is the major treatment strategy, and postoperative recurrence or malignant transformation of labial PA was extremely rare.

A Review of the Current Literature on Pleomorphic Adenoma

Pleomorphic adenomas (PA) are the most common benign salivary gland tumors. They arise from the major salivary glands, as well as the minor salivary glands. They may arise rarely from the palate, oral cavity, neck, and nasal cavity also. Yet, the fourth, fifth, and sixth decades of life are the most common for them to manifest. Forty percent of them occur in males and 60% in females. It is a benign mixed tumor, which has three components: an epithelial component, a myoepithelial cell component, and a mesenchymal component. A fibrous capsule separates these cells from the surrounding tissues. It generally presents as a slowly progressing painless swelling, which is well-delineated, nonsymptomatic, and not involving the facial nerve. Salivary gland tumors can be accurately diagnosed before surgery using fine-needle aspiration (FNA), ultrasonography (USG), and computed tomography (CT) scan. Calponin, cluster of differentiation 9 (CD9), glial fibrillary acidic protein (GFAP), Mcl-2, metastasis suppressor gene (NM23), p63, S-100, smooth muscle actin (SMA), and SRY-box transcription factor 10 (SOX10) exhibit the majority of the positive reactions in pleomorphic adenomas. The diagnostic marker pleomorphic adenoma gene 1 (PLAG1) is frequently employed since it is specific for pleomorphic adenoma. Although benign, these epithelial tumors have a propensity to recur and undergo malignant transformation if incompletely excised, leading to increased morbidity in these patients. A review of the consensus guidelines and literature was conducted, and the online literature on the subject from 2002 was included. This article is not a complete review of all the available literature; rather, it is a comprehensive review of the topic.

Heterotopic sites of pleomorphic adenoma

The majority of the tumours occurring in minor salivary glands are malignant with only 18% being benign. Among the benign tumours, pleomorphic adenoma is the most common. Although it presents more commonly in the parotid and submandibular glands, it can occur at any site where salivary glands reside. Only 6.4% of cases of pleomorphic adenoma occur in minor salivary glands, e.g. palate, cheeks, lips, para-pharyngeal space, etc. It occurs in females in the fourth or fifth decade. It presents as an asymptomatic and slow-growing mass. The treatment of choice is wide local excision due to the high rate of recurrence and malignant potential. We present rare case reports of two patients. The first case is of a young 18 years female presenting with recurrent neck (anterior triangle) swelling and the second case is of a 46-year-old female presenting with lower lip swelling. In both cases, it was a slow-growing mass and asymptomatic. Cytological examination of the lesion revealed the diagnosis of pleomorphic adenoma. It was completely excised with no post-operative complication. Pleomorphic adenoma, although a common benign neoplasm of major salivary glands, should always be kept as a possibility at the locations of minor salivary glands. As pleomorphic adenoma can transform into a malignant counterpart, therefore early diagnosis and treatment of the lesion can prevent further complications. The prognosis of pleomorphic adenoma is excellent. However, a close follow-up of the patient is required due to the high rate of recurrence.

Lip pleomorphic adenomas: case series and literature review

BACKGROUND

Pleomorphic adenoma (PA) is the most frequent benign salivary gland tumor, but a lip PA is rare. Although this tumor may be definitively diagnosed by imaging or a tissue biopsy if it is reasonably large, PAs on the lip are relatively small, and they present findings that are similar to those of other lip lesions, which can make a preoperative diagnosis difficult.

METHODS

We analyzed all PAs in the oral region and lesions on the lips treated in our department over the past 20 years, and we discuss them together with the relevant literature.

RESULTS

We found that 11.8% (n=6) of the PAs occurred on a lip (upper lip: 9.8%, lower lip: 2.0%), and ~1% of all mass lesions of the lips were PAs. The average size of the lip PAs was 1.5±0.7 cm (range, 0.7-2.2 cm). For preoperative diagnostic assistance, ultrasonography (US) (n=4), magnetic resonance (MR) (n=3), or no imaging (n=2) was used. An excisional biopsy was performed in all cases, and to date, no recurrence or malignant transformation has been observed.

CONCLUSIONS

Lip PA is relatively rare. Because almost all of these lesions are small, a preoperative diagnosis is more difficult compared to palatal lesions. This tumor is also prone to long-term neglect and has the potential for recurrence and malignant transformation. It is thus necessary to perform an excision that includes the capsule and surrounding tissues, and careful postoperative follow-up should be continued.

Novel Technique for the Surgical Management of Pleomorphic Adenoma of the Upper Lip

Pleomorphic adenoma (PA) is one of the most common benign lesions of the salivary glands, with a majority of them occurring in the parotid gland. PA has origin from the epithelial and mesenchymal elements and can arise from both major and minor salivary glands. Among minor salivary glands, the palate is the most commonly affected site, followed by lips, cheeks, gingiva, the floor of the mouth, and tongue. PA of the upper lip without intraoral mucosal involvement is a rare entity. In this article, we report a case of PA of the upper lip in a middle-aged female patient and its surgical management with a novel technique. During six months’ postoperative review, the patient showed excellent wound healing with very minimal scar formation.

Comprehensive characterization of pleomorphic adenoma at intraoral unusual sites

OBJECTIVE

The present study aimed to comprehensively characterize the epidemiologic characteristics, clinicopathologic characteristics, clinical treatments, and prognoses of pleomorphic adenoma (PA) identified at unusual intraoral sites.

STUDY DESIGN

Patients diagnosed with PA in oral and maxillofacial regions at our institution in the past 16 years (2005-2020) were screened from the inpatient disease registry. All data concerning patients with PA found at unusual intraoral sites (defined as intraoral locations except sublingual gland and palate) were retrieved. Previously published cases with adequate clinicopathologic data were collected from PubMed and Embase. Eligible cases were further reviewed and included for statistical analyses.

RESULTS

Among 1039 cases of PA diagnosed at our institution, 52 lesions were found at unusual intraoral sites. A literature review identified another 63 eligible cases from 32 articles. The upper lip was the most common sites for these lesions (n = 57), followed by buccal mucosa (n = 34), tongue (n = 8), lower lip (n = 8), and retromolar area (n = 2). Recurrence and malignant transformation after surgical resection were extremely rare for these lesions.

CONCLUSIONS

PA might rarely develop at uncommon intraoral sites with atypical presentations, thus complicating its early diagnosis. Surgical resection is the major therapeutic strategy for this rare entity and has a favorable prognosis.

A miscellany of cribriform pattern, squamous metaplasia and clear cells in pleomorphic adenoma of upper lip: A diagnostic paradox

Pleomorphic Adenoma (PA), a benign neoplasm of glandular origin most commonly involves major salivary glands. It is rare in minor salivary glands such as hard palate, upper lip and buccal mucosa, frequently affecting middle aged females. PA comprises diverse histopathologic features of epithelial, myoepithelial and mesenchymal components. Aberrant histopathologic features in Pleomorhic Adenoma thus calls for judicious discrimination from alike entities which facilitates appropriate surgical management. Here we present a case report of PA in upper lip in a 25 year old female patient showing uncommon findings like clear cells, squamous metaplasia and cribriform pattern.

Pleomorphic Adenoma: A Systematic Review

Background

Pleomorphic adenoma (PA) is a commonly occurring benign tumor originating in the salivary glands.

Objective

The aim was to carry out a systematic literature of reports on pleomorphic adenoma from 2000 to 2018 to determine patient's age spread, gender, anatomical location, capsular invasion, histopathology, treatment and patient outcome.

Materials and methods

A PubMed search was conducted with the following key words: adenoma, pleomorphic adenoma, and mixed salivary tumor.

Results

Twenty-two articles in English were read in full after fulfilling the eligibility criteria. The mean age of PA occurrence was 44.14 years with a definite female predilection (M:F ratio = 13:8). It most commonly occurred in the facial region (42.85%), and surgical approach is the preferred intervention.

Conclusion

Pleomorphic adenomas are benign salivary gland neoplasms that can grow into extensive sizes if left untreated and hence need to be diagnosed early. Complete excision of the tumor is the definitive treatment, as enucleation can result in recurrence. Facial nerve has to be preserved if PA occurs in the parotid gland.

How to cite this article

Almeslet AS. Pleomorphic Adenoma: A Systematic Review. Int J Clin Pediatr Dent 2020;13(3):284-287.

Pleomorphic Adenoma in the Lower Lip: A Case Report and a Review

Pleomorphic adenoma constitutes 50% of salivary gland tumors affecting mostly the parotid gland extraorally, and the palate intraorally. While the upper lip is a common site, it is unusual to encounter this tumor in the lower lip. A 26-year-old man complained of a persistent lump affecting the lower lip. The lesion was excised and was shown on histopathological examination to be a pleomorphic adenoma with squamous metaplasia. At the 18-month review appointment, there was complete healing and no recurrence. Pleomorphic adenoma in the lower lip should be considered among the differential diagnosis of lower labial swellings, especially in young patients. There needs to be reconsideration of the epidemiological and histological characteristics.