Pleomorphic adenoma

Pleomorphic adenoma histology is a term used to describe the detailed analysis of the adenoma tumors that are found in the glandular tissue in the various endocrine glands. This process involves the examination of a section of the tumor under a light or electron microscope. Pleomorphic adenoma histology is further enhanced with the aid of histological stains.

Different types of adenomas are found to produce different results when stains were applied on them, thus histological evidence became an important tool for identification of the adenomas. In most cases it is very difficult to identify the tumors, thus pleomorphic adenoma histology is applied. The process is performed by trained doctors and medical experts in the field of adenoma pathology.

This team of experts diagnoses the adenoma histology, in order to ascertain the diagnosis of the adenoma based on the observations. By nature, biological tissue that is found in the tumors reacts differently to stains like haematoxin and eosin. A good example of the use of pleomorphic adenoma histology is the classification of pituitary tumors.

Although, new technology is applied for the classification of the pituitary adenoma, in the earlier days the pituitary adenoma histology included three types of tumors known as basophilic adenomas, acidophilic adenomas and chromophobes. This classification was based on the differential reaction of the tumors to staining method. Today, the pituitary tumors are subdivided based on the type of hormone that is secreted by the tumors.

Based on the results of the pleomorphic adenoma histology tests, the mode of treatment is decided. If the tumor is small in size and benign, the adenoma is observed for any type of cancerous activity before a surgery is performed in order to remove the tumor. Pleomorphic adenoma pathology is concerned with the diagnosis of the adenoma tumor based on a detailed examination of the tumors. Adenoma is benign cancerous growth that is found on the glandular tissue of the endocrine glands.

The adenoma is inactive in the initial stages, but later as the disease remains undetected, it may also transform into a precancerous stage followed by malignancy. Pleomorphic adenoma pathology is the key to assess the stage of the adenoma. The field of pathology has many prospects, especially in the field of adenoma pathology. There are various options to choose from, including surgical, pathology, cytopathology and forensic pathology.

One is required to have completed medical school and then acquired a qualification in any of the fields in pathology. Pleomorphic adenoma pathology is a specialization in the application of the various pathological methods in identifying the adenoma. According to results produced for the pleomorphic adenoma pathology, the course of action for the treatment of the adenoma is ascertained. If the adenoma is small in size and painless, it is observed for a period of time before any action is taken.

While in the case of precancerous tumors, the adenoma is removed immediately and the patient is also subjected to radiation therapy, in order to completely eradicate the disease. Pleomorphic adenoma pathology is strategic in diagnosing various types of adenomas in the human body. A large number of tests are conducted in order to conduct a detailed analysis of the cancerous tumors.

The patient may also need to undergo surgery for removal of the tumor from the body. Various sophisticated equipment is easily available in the pathology lab that aids in enhancing the accuracy of the test results.

If the pleomorphic adenoma of benign nature is not treated well, then it leads to transform itself into a malignant tumor called the carcinoma ex benign pleomorphic adenoma, and this if formed in the parotid gland is called the carcinoma ex benign pleomorphic adenoma of the parotid gland. Histologically speaking, the diagnosed carcinoma of the pleomorphic adenoma is actually a subtype of the primary parotid malignancy.

According to researches, the features of the already treated salivary pleomorphic adenoma has got 25% of the cases with malignancy showing the nonspecific characteristics overall.

The preoperative investigations comprise of the fine-needle aspiration cytology (which shows low sensitivity for this adenoma), CT scans and the MRI scans, and the post treatment effects show the resection of the facial nerves en bloc with the tumor in some cases and good reconstruction of the recent-onset facial paresis in the other cases.

Usually about 44% of the patients have a complete histologic removal of the tumor and this refers to the most significant survival rate. But the locoregional control rate for the carcinoma pleomorphic adenoma is only 66% in the 5-year duration of the recovery time making the recurrence of the disease invariably fatal, and even the 44% of the disease-specific specific cases report to high rate of mortality accounting to 87%.

Also, the carcinoma in the pleomorphic adenoma of the parotid gland is actually difficult to be diagnosed in the preoperative stages, and despite of the good control of the locoregional disease through surgery and the radiotherapy, the carcinoma ex benign pleomorphic adenoma delivers a high disease-specific mortality rate.

Observing the most significant prognostic factor due to the incomplete surgery resection, surgeons advocate some effective alternatives like radical ablative surgery, the imminent reconstruction of the soft tissue and the nerves, and a good index of clinical suspicion in order to avoid the development of the carcinoma in the pleomorphic adenoma of the parotid gland.

When the benign pleomorphic adenoma transforms into a malignant tumor, then a carcinoma ex pleomorphic adenoma (CXPA) is formed. The carcinoma ex pleomorphic adenoma contains the malignant epithelium (salivary duct carcinoma, nonspecific adenocarcinoma, terminal duct carcinoma, undifferentiated carcinoma, or myoepithelial carcinoma) along with the benign stroma.

This carcinoma ex pleomorphic adenoma is an aggressive type of the pleomorphic salivary adenoma or the salivary gland malignancy, and rarely occurs in the salivary gland. And the direct cavernous sinus (CS) invasion of the soft palate is also an extremely rare case, and usually a biopsy of the soft palatal tumor displays the presence of the pleomorphic adenoma.

The differential diagnosis of the possibility of the presence of the pleomorphic adenoma as carcinoma is mostly done through the radio imaging therapies, where the Magnetic Resonance Imaging (MRI) scans show the tumor having the left maxilla, being stretched to the cavernous sinus (CS) from the pterygopalatine fossa and the inferior orbital fissure.

It is only after the surgery excision of the tumor, that the CXPA gets revealed. And the patients are also advocated the adjuvant concomitant chemo-radiation therapy (CCRT) for the treatment. The recurrence of the tumor of the pleomorphic adenoma is possible again 5 months after the treatment in the left carvenous sinus has been done with the CCRT therapy.

The status of the disease is usually stable even after two years of the diagnosis of the CXPA. Doctors say that the patient with pleomorphic adenoma or the carcinoma symptoms like proptosis, facial numbness and the blurred vision must be observed vigilantly for the tumor invading the carvenous sinus from the perineural spread.

Pleomorphic Adenoma occurring in the Base of the Tongue

The common occurrence site for the pleomorphic adenoma is the palate in the minor salivary glands. Though the most common sites for its occurrence are the major salivary glands, but in the case of the minor salivary glands, a very few instances were revealed involving the tongue base and the subsequent valleculae.

The pleomorphic adenoma tumors consist of 3% of all the neoplasms, and in the minor salivary glands it is in the range 9%-22%. The malignant tumors in the tongue region occur more often, and they are usually the adenoid cystic carcinoma, the adenocarcinoma, and the mucoepidermoid carcinoma.

But the overall occurrence of the pleomorphic adenoma of the base of the tongue can be diagnosed when there is a routine examination of the patient or the worsening dysphagia. The demographic information includes the average age of 50 years in a person for the occurrence of the pleomorphic adenoma where the ratio of the males to females is 1:1.

The histopathological manifestations of the pleomorphic adenoma of this kind also include the epithelial and the myoepithelial components. The MRI (magnetic resonance imaging) is the effective way to deal with the nature and the extent of the tumor which also involves the lymph nodes and the affected regions around the tumor.

The treatment of the pleomorphic adenoma of the base of the tongue is basically surgical and is dependent on various factors such as the size and the location of the tumor and the age of the patient. The recurrence rate is 6% when the tumor is benign.

Middle Ear Pleomorphic Adenoma is the Extreme Case

The occurrence of the pleomorphic adenoma in the middle ear region is an extremely rare case. The mixed tumor developing in the ear is already a rare disease but in the middle ear, it is very rare. Though the diagnosis, treatment and the prognosis of the disease have not been reported much, but the recurrence of the pleomorphic adenoma of the middle ear is reported.

Histopathologically, the pleomorphic adenoma contains the glandular epithelial and the myoepithelial components, but immunohistochemically, it shows a focal spread of the possibility to spread to the cytokeratin and s100 protein in the epithelial and the mesenchymal elements of the neoplasm.

Comparatively, the immunohistochemistry show more significance in diagnosing the formulation of the tumor in the middle ear, as the middle ear exhibits a single layer of the epithelial cells and does not have the myoepithelial component. According to recent studies, the pleomorphic adenoma in the middle ear has got both the epithelial and the neuroendocrine elements also.

As said earlier, the pleomorphic adenoma rarely occurs in the ear, but is mainly seen in the external auditory canal. The pleomorphic adenoma of the middle ear possibly has three locations of formulation namely the ceruminal glands of the external auditory canal, metaplasia of the middle ear mucosa or the ectopic salivary gland.

Of all these places of origin, the pleomorphic adenoma is formed mainly from the ectopic salivary gland tissues. Since mostly the lesions are localized and non-invasive, the immunohistochemistry is most significant in diagnosing the definite presence of the middle ear pleomorphic adenoma.

It is also not unnoticeable that the tumor recurs after 20 years post resection; hence, postoperatively the follow-ups are important, along with the resection at the recurrence which is effective in dealing with the middle ear pleomorphic adenoma.

Pleomorphic Adenoma of the Skin Involving Eyelid

The pleomorphic adenoma of the skin which is also called as the chondroid syringoma where the eyelid is concerned is a very rare kind of adenoma. Having eccrine or apocrine differences, the cases reported for this kind of adenoma have actually been mentioned in the Indian literature. Normally being encapsulated, the sweat gland tumors are basically solitary and usually benign in nature while appearing to be hard circumscribed masses in the skin.

They mainly grow slowly and asymptomatically, but at the same time adopting a good size with the polypoid term. The pleomorphic adenoma of the eyelid is one of the rarest cases that is come across by the researchers or even the surgeons, as its incidence being only 0.48% reportedly.

This is from the inference of a research on 207 cases of tumors where only one case of a tumor like lesion of the eyelid was reported. The term chondroid syringoma was introduced by Hirsch and Helwig in 1961 to replace the pleomorphic adenoma or the mixed tumor of the skin, because of the epithelial nature that arise from the components of the sweat gland along with the secondary changes in the stroma which resembles a cartilage.

This pleomorphic adenoma of the eyelid apart from being asymptomatic, also show well-circumscribed structure in the skin which lies in the size range 0.3 mm – 0.5 mm in diameter. There are two types of chondroid syringoma or the pleomorphic adenoma of the eyelid based on the morphological picture.

The first type can be the tubular, branching lumina and the second type is the small tubular lumina where glands are arranged in single layer of flat epithelial cells. The pleomorphic adenoma of the skin involving eyelid can have either eccrine or apocrine components, and very rarely transforms into malignancy bringing widespread metastases.

Giant Pleomorphic Adenoma of the Intraoral Site

The 50 percent of the tumors occurring in the major and the minor salivary glands are related to the pleomorphic adenoma. The adenoma accounts to about 70 percent of the tumors in the minor salivary glands, where it is widely found in the intraoral site which is the palate. The upper lip and the buccal mucosa follow the intraoral site. This pleomorphic adenoma appears to be a painless structure initially and does not result in the ulceration of the overlying mucosa.

Hence, it appears to be mobile except when it appears in the hard palate. About 25 percent of the benign mixed adenomas transform themselves into malignant adenomas. Considering the large soft palate tumor, this intraoral mixed tumor can be well encapsulated often leading to symptoms of the abnormal speech and dysphagia.

When the pleomorphic adenoma, a benign heterogeneous tumor, occurs in the soft palate region, the palatal tumor is usually a slow growing and painless mass for several years unless it becomes big enough to badly affect the respiration or the mastication.

Preoperatively, the Magnetic Resonance Imaging (MRI) technique is the way to confirm the presence of the pleomorphic adenoma of the soft palate which usually does not extend itself to the parapharyngeal space from the oropharynx.

Hence, to rule out the parapharyngeal space origin or extension, imaging is preferably done before attempting the transoral surgical approach. In this case, it is better to proceed for external approach to get better picture and have good control over the regional cranial nerves and the vessels around.

The complete surgical excision is the best treatment choice to deal with the disease of the giant pleomorphic adenoma of the soft palate. Post surgery, the patients regain their normal speech and swallowing abilities and there need not be any prominent changes in the soft-palate anatomy.