Mucoepidermoid carcinoma (MEC) is a malignant salivary gland neoplasm with extreme morphologic heterogeneity and hence rendering a definitive fine needle AbstractIntroductionMaterials and MethodsDiscussion
The cases were grouped into low, intermediate and high grade based on the standard grading system for MEC. Special stain for mucin (mucicarmine, PAS-D or alcian AbstractIntroductionMaterials and MethodsDiscussion
Classification
Mucoepidermoid carcinoma cell types are classified histologically as low, intermediate, and high-grade types.
High-grade tumors are poorly differentiated, and they are made up primarily of squamous epithelial and intermediate cells.
Low-grade tumors are well differentiated and are made up primarily of mucus-secreting and squamous epithelial cells. .
,
Diagnosis
The infrequency of reports of mucoepidermoid carcinoma of the subglottis, and of the larynx in general, may be attributable to the relative difficulty that physicians have in recognizing this tumor type when it occurs outside the salivary glands.
In addition to the possibility of sampling errors, interpretative errors during analysis of tumor speci.
,
Management
The appropriate management of mucoepidermoid carcinomas of the larynx is unsettled, but most authors agree that different treatment approaches are indicated for different tumor subsites and histologic grades.
High-grade tumors are usually treated in a more aggressive fashion, with surgery as the primary modality, as is the case with high-grade tumo.
,
Morphology
MECs may be circumscribed and variably capsulated or infiltrative and fixed; the latter characteristics generally apply to higher-grade tumors.
Areas of scarfing are relatively common.
Most tumors are smaller than 4 cm in diameter.
Cysts of variable sizes are often present, and they usually contain brownish fluid.
MEC cells form sheets, islands, du.
,
Pathophysiology
The tumor is primarily made up of three cell types in widely varying proportions: intermediate, mucous, and epidermoid Higher-grade tumors show evidence of cytologic atypia, a high mitotic frequency, and areas of necrosis, and they are more likely to show neural invasion.
Stromal hyalinization is common and sometimes extensive.
It has been proposed.
,
Research
MECs exhibit remarkable variability in their clinical behavior.
Several microscopic grading systems based on a numerical score have been advocated as a means of predicting outcome.
These systems rely on subjective evaluations of the relative proportions of the various cell types, the degree of cellular atypia, mitotic frequency, presence of necrosi.
,
Signs and symptoms
The tumor usually forms as a painless, fixed, slowly growing swelling of widely varying duration that sometimes goes through a phase of accelerated growth immediately before clinical presentation.
Symptoms include tenderness, otorrhea, dysphagia, and trismus.
Intraoral tumors are often bluish-red and fluctuant, and they may resemble mucoceles or va.
,
What are the characteristics of mucoepidermoid carcinoma (MEC)?
Mucoepidermoid carcinoma, low grade.
Intermediate cells and mucus-secreting cells in pseudopapillary clusters and cyst formation (H&E stain) Smears in MEC are usually hypercellular and cell rich and stroma rich.
MEC belongs to the group of tumors exhibiting predominant epithelial cell morphology.
,
What is the survival rate for mucoepidermoid cancer?
Pires et. al. reviewed the literature and reported that overall 5-year survival rates ranged from 0 to 43% for patients with high-grade mucoepidermoid cancers of the salivary glands, 62 to 92% for patients with intermediate-grade tumors, and 92 to 100% for patients with low-grade tumors.
,
Where can a capsule be seen in low grade Mucoepidermoid carcinoma?
Areas suggesting a capsule can be seen in low grade mucoepidermoid carcinoma Varying proportions of epidermoid cells, intermediate cells and mucocytes Mucous cells embedded in epidermoid cell nests or lining cystic spaces Intermediate cells found within epidermoid cell nests or forming separate nests .
,
Why is mucoepidermoid carcinoma of the subglottis infrequent?
The infrequency of reports of mucoepidermoid carcinoma of the subglottis, and of the larynx in general, may be attributable to the relative difficulty that physicians have in recognizing this tumor type when it occurs outside the salivary glands.
