Pleomorphic adenoma of the upper lip

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.

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.

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.