Hyalinizing clear cell carcinoma (HCCC) is a rare
malignant salivary gland tumour, with a good prognosis, that is usually found on the
tongue or
palate.
Signs and symptoms
HCCCs typically present as a painless mass in the
mouth
In animal anatomy, the mouth, also known as the oral cavity, or in Latin cavum oris, is the opening through which many animals take in food and issue vocal sounds. It is also the cavity lying at the upper end of the alimentary canal, bounded on ...
.
Diagnosis
HCCCs are diagnosed by examination of tissue, e.g. a
biopsy.
Pathology
HCCC consist of cells with abundant clear
cytoplasm, arranged in cords, trabeculae or clusters in a
hyalinized stroma.
Nuclear pleomorphism
Pleomorphism is a term used in histology and cytopathology to describe variability in the size, shape and staining of cells and/or their nuclei. Several key determinants of cell and nuclear size, like ploidy and the regulation of cellular metab ...
is usually minimal and
mitoses are infrequently seen.
Owing to their
glycogen
Glycogen is a multibranched polysaccharide of glucose that serves as a form of energy storage in animals, fungi, and bacteria. The polysaccharide structure represents the main storage form of glucose in the body.
Glycogen functions as one o ...
content, which explains the "clear" appearance under the
microscope, tumour cells stain with
PAS.
Immunostain
In biochemistry, immunostaining is any use of an antibody-based method to detect a specific protein in a sample. The term "immunostaining" was originally used to refer to the immunohistochemical staining of tissue sections, as first described by A ...
s for
S100 and
smooth muscle actin
Smooth may refer to:
Mathematics
* Smooth function, a function that is infinitely differentiable; used in calculus and topology
* Smooth manifold, a differentiable manifold for which all the transition maps are smooth functions
* Smooth algebrai ...
(SMA) are typically negative, but positive for
cytokeratins and
epithelial membrane antigen (EMA).
HCCCs typically have a recurrent
chromosomal translocation, t(12;22), involving the genes
EWSR1 and
ATF1.
The same translocation is seen in
clear cell sarcoma
Clear cell sarcoma is a rare form of cancer called a sarcoma. It is known to occur mainly in the soft tissues and dermis. Rare forms were thought to occur in the gastrointestinal tract before they were discovered to be different and redesignated a ...
.
The
histologic
Histology,
also known as microscopic anatomy or microanatomy, is the branch of biology which studies the microscopic anatomy of biological tissues. Histology is the microscopic counterpart to gross anatomy, which looks at larger structures vis ...
differential diagnosis
In healthcare, a differential diagnosis (abbreviated DDx) is a method of analysis of a patient's history and physical examination to arrive at the correct diagnosis. It involves distinguishing a particular disease or condition from others that p ...
includes
mucoepidermoid carcinoma (clear cell variant),
acinic cell carcinoma
Acinic cell carcinoma is a malignant tumor representing 2% of all salivary tumors. 90% of the time found in the parotid gland, 10% intraorally on buccal mucosa or palate. The disease presents as a slow growing mass, associated with pain or tendern ...
(clear cell variant),
epithelial-myoepithelial carcinoma
Epithelial-myoepithelial carcinoma (EMCa) is a rare malignant tumour that typically arises in a salivary gland and consists of both an epithelial and myoepithelial component. They are predominantly found in the parotid gland
and represent approxim ...
and metastatic
clear cell carcinoma
Clear-cell carcinoma, also known as clear-cell adenocarcinoma and mesonephroma, is an epithelial-cell-derived carcinoma characterized by the presence of clear cells observed during histological, diagnostic assessment. This form of cancer is classi ...
.
Image: Hyalinizing clear cell carcinoma - intermed mag.jpg , Intermed. mag.
Image: Hyalinizing clear cell carcinoma - very high mag.jpg , Very high mag.
Prognosis
They generally have a good prognosis.
See also
*
References
{{Tumors of lip, oral cavity and pharynx
Rare cancers
Salivary gland neoplasia