z We report a high grade mucoepidermoid carcinoma arising in a background of sialadenoma papilliferum, at the base of the tongue, an unusual location for minor salivary gland neoplasms

(1)

口腔病理科 On-Line KMU Student Bulletin

- 1 -

原文題目(出處)： Mucoepidermoid carcinoma arising in a background of sialadenoma papilliferum: A case report. Head and Neck Pathol 2009;3:59-62

原文作者姓名： Wei Liu A Douglas R. Gnepp A Egbert de Vries A Haidy Bibawy A Marshall Solomon A, Elizabeth S. Gloster

通訊作者學校： SUNY Downstate Medical Center, Albert School of Medicine at Brown University, SUNY Downstate Medical Center

報告者姓名(組別)： Intern A組李存恩

報告日期： 98/10/09

內文：

Abstract & Introduction

z Sialadenoma papilliferum is a rare tumor, primarily of minor salivary gland origin

z It is both an exophytic and endophytic papillary lesion histologically resembling syringocystadenoma papilliferum of sweat gland.

z The tumor is considered benign although rare recurrent cases have been reported.

z We report a high grade mucoepidermoid carcinoma arising in a background of sialadenoma papilliferum, at the base of the tongue, an unusual location for minor salivary gland neoplasms.

z Eleven months after excision and nodal dissection, there is no evidence of recurrence or metastasis.

Case Report

z P’t: An 82-year-old female with medical history of diabetes mellitus and hypertension z P.I.: 3-month history of dysphagia secondary to a 2-cm papillary, exophytic mass at the left

base of the tongue.

z Diagnosis：High grade mucoepidermoid carcinoma arising in a background of a Sialadenoma papilliferum.

z Tx.: tumor excision and follow- up margin excision with level II, III and IV left neck lymph node dissection.

z Biopsy test: No residual tumor was identified and four lymph nodes were negative for tumor.

All specimens were negative for microvascular invasion.

z F/u: regularly followed-up and no recurrence of the tumor was documented eleven months after the surgery.

(2)

- 2 -

Microscopically findings of the lesion

z Prominent papillarity in some areas, appears to be centered around an excretory minor salivary gland duct.

z The opening of the duct is in direct continuity with the stratified acanthotic squamous epithelium covering the papillary areas of the tumor

z Ductal epithelium is bi-layered or stratified →

tall columnar cells in the luminal layer ； short, cuboidal cells in the basal layer.

z Scattered goblet cells and ciliated metaplastic cells are interspersed.

z Extensive squamous metaplasia is present focally.

z The papillary fronds of the tumor, which are supported by fibrovascular cores, protrude into the ductal space.

z Lymphocytic and plasmacytic inflammation

is present in the cores.

====== > Sialadenoma Papilliferum

z The deeper and malignant portion of the tumor： more solid pattern with well defined Squamous differentiation, intermediate cells, and nests of gland-like structures.

z (Fig.c) Mucicarmine stain for mucoepidermoid carcinoma, demonstrating both intraglandular and intracellular mucin.

z Nuclear pleomorphism, hyperchromasia, and high mitotic activity are evident in the squamous component

z Close association with adjacent salivary ductal epithelium, and with the deeper portion of sialadenoma papilliferum.

====== > High grade (Brandwein grading system) mucoepidermoid carcinoma arising in a background of sialadenoma papilliferum.

(3)

- 3 -

Discussion

¾ Sialadenoma papilliferum older males

minor salivary glands - palate, buccal mucosa, retromolar pads and lips

1. The base of tongue location, as in our case, has not been documented previously, although minor salivary glands are found in this location.

2. The proliferative, dilated salivary gland ducts with papillary fronds protruding into the lumen, together with the hyperplastic, hyperkeratotic overlying squamous epithelium, == >

Sialadenoma papilliferum, continuous with a deeper high grade mucoepidermoid carcinoma.

3. The true origin and nature of sialadenoma papilliferum have been controversial.

1. Neoplasm that originates from ductal surface cells – ( ciliated cells in the lining epithelium of the duct)

2. Focal hyperplasia following blockage of a salivary gland duct

4. Although mucoepidermoid carcinoma can be associated with a large excretory salivary duct, a papillary, proliferating ductal lesion, as in this case, is not a feature.

5. Considering the papillary architecture of the lesion, our differential diagnosis (1) a sialadenoma papilliferum with a papillary squamous cell carcinoma

 resemble sialadenoma papilliferum in its gross appearance, However, a glandular component with mucin-secreting cells is not present in this lesion.

(2) an adenosquamous carcinoma with prominent papillary features

Having distinctively separate components of adeno- and squamous differentiation with no papillary configuration

(3) papillary squamous cell carcinoma (4) a papillary cystadenocarcinoma

 It does not include squamous elements

題號題目

1 Which of the following is not the characteristic of mucoepidermoid carcinoma?

(A) Most common in minor salivary gland, especially the palate.

(B) Most common malignant salivary tumor in children.

(C) Composed of a mixture of mucus-producing cell and squamous cell.

(4)

- 4 -

(D) The epidermoid cell is rarely keratinized.

答案(A ) 出處：Oral & Maxillofacial pathology P.420

題號題目

2 Which of the following is not the factor that mucoepidermoid carcinoma be categorized into one of three histopathologic grades?

(A) Amount of cyst formation (B) Degree of cytologic atypia (C) Mitotic stage of epidermoid cells

(D) Relative numbers of mucous, epidermoid, and intermediate cell 答案(C) 出處：Oral & Maxillofacial pathology P.420