Polymorphous low-grade adenocarcinoma
Encyclopedia
Polymorphous low-grade adenocarcinoma, often abbreviated PLGA, is a rare, slow-growing malignant
salivary gland
tumor
. It is most commonly found in the palate
.
The name of the tumor derives from the fact that:
Microscopically
, its histology
can be confused with an adenoid cystic carcinoma
and a pleomorphic adenoma
.
Malignant
Malignancy is the tendency of a medical condition, especially tumors, to become progressively worse and to potentially result in death. Malignancy in cancers is characterized by anaplasia, invasiveness, and metastasis...
salivary gland
Salivary gland
The salivary glands in mammals are exocrine glands, glands with ducts, that produce saliva. They also secrete amylase, an enzyme that breaks down starch into maltose...
tumor
Tumor
A tumor or tumour is commonly used as a synonym for a neoplasm that appears enlarged in size. Tumor is not synonymous with cancer...
. It is most commonly found in the palate
Palate
The palate is the roof of the mouth in humans and other mammals. It separates the oral cavity from the nasal cavity. A similar structure is found in crocodilians, but, in most other tetrapods, the oral and nasal cavities are not truly separate. The palate is divided into two parts, the anterior...
.
The name of the tumor derives from the fact that:
- It has a varied microscopic architectural appearance, i.e. it is polymorphous.
- It is non-aggressive when compared to other oral cavity tumors, i.e. it is a low-grade tumor.
- It forms glands, i.e. it is an adenocarcinomaAdenocarcinomaAdenocarcinoma is a cancer of an epithelium that originates in glandular tissue. Epithelial tissue includes, but is not limited to, the surface layer of skin, glands and a variety of other tissue that lines the cavities and organs of the body. Epithelium can be derived embryologically from...
.
Histology
PLGAs consist of a monomorphous cell population that has a varied histologic morphology.Microscopically
Microscope
A microscope is an instrument used to see objects that are too small for the naked eye. The science of investigating small objects using such an instrument is called microscopy...
, its histology
Histology
Histology is the study of the microscopic anatomy of cells and tissues of plants and animals. It is performed by examining cells and tissues commonly by sectioning and staining; followed by examination under a light microscope or electron microscope...
can be confused with an adenoid cystic carcinoma
Adenoid cystic carcinoma
Adenoid cystic cancer is a rare type of cancer that can exist in many different body sites. It most often occurs in the areas of the head and neck, in particular the salivary glands; but has also been reported in the breast, lacrimal gland of the eye, lung, brain, bartholin gland, trachea, and...
and a pleomorphic adenoma
Pleomorphic adenoma
Pleomorphic adenoma is a common benign salivary gland neoplasm characterised by neoplastic proliferation of parenchymatous glandular cells along with myoepithelial components, having a malignant potentiality. It is the most common type of salivary gland tumor and the most common tumor of the...
.