Pleomorphism

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pleomorphism

[‚plē·ō′mȯr‚fiz·əm]
(biology)
The occurrence of more than one distinct form of an organism in a single life cycle.
(crystallography)

Pleomorphism

 

an environmentally produced change in the incidence of disease and causes of death as well as in the properties of individual diseases, that is, nosologic entities (see NOSOLOGY).

During the 20th century, extensive immunization of populations and nationwide preventive measures in economically developed countries have eradicated many infectious diseases, for example, plague and poliomyelitis, and have sharply reduced infant mortality caused by infectious diseases. Changes in living conditions have reduced the incidence of diseases that stem from nutritional deficiency, for example, avitaminoses and iron-deficiency anemia. On the other hand, the incidence of injuries, tumors, and cardiovascular and viral diseases has increased.

New hereditary and occupational diseases have resulted from such environmental changes as those that accompany the growth of the chemical industry. Therapy-induced pleomorphism is a change in the clinical picture of a disease as a result of treatment. For example, the use of drugs has led to the disappearance of severe forms of thyrotoxicosis and anemia. Similarly, tuberculous meningitis, comas in diabetes mellitus, and acute pulmonary suppuration have become rare. In leukemia, tumor cells have disappeared from bone marrow because of the use of cytostatic agents, but they multiply in the nervous system and viscera. Undesirable side effects may follow medicinal treatment, and beyond a certain intensity these constitute a drug disease. The aftereffects of gastric or cardiac surgery, for example, can also give rise to disease.

Diseases that have received a new nosologic classification because of the growth of medical knowledge should not be considered examples of pleomorphism.

REFERENCES

Davydovskii, I. V. Patologicheskaia anatomiia i patogenez boleznei cheloveka, 3rd ed., vols. 1–2. Moscow, 1956–58.
Shul’tsev, G. P. “Terapevticheskii patomorfizm.” Klinicheskaia meditsina. 1973, no. 6.
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However, because florid describes an architectural, rather than a cytologic, feature, pleomorphic LCIS can also be described as growing in a florid pattern and having cells of varying nuclear grades commonly coexisting in florid LCIS.
of Cases Percentage No Gland Mass (n=16) 1 Pleomorphic adenoma 11 47.
conducted a mutational analysis in spinal pleomorphic xanthoastrocytomas (SPXA) that failed to reveal the V600E BRAF mutation that is commonly present in cerebral PX.
Paraffin embedded blocks of 63 cases of pleomorphic adenoma of salivary glands reported at Histopathology departments of University of Health Sciences, King Edward Medical College/Mayo Hospital, Fatima Jinnah Medical College/ Ganga Ram Hospita and Sheikh Zayed Hospital Lahore from January 2013 to August, 2015 were included in the study.
Out of 66 benign tumors, pleomorphic adenoma were 57(73.
A total of 182 diagnosed cases of pleomorphic adenoma, mucoepidermoid carcinoma and adenoid cystic carcinoma of Salivary glands reported at Histopathology Departments of University of Health Sciences,King Edward Medical University/Mayo hospital, Sheikh Zaid hospital and Fatima Jinnah Medical University for women/Ganga Ram Hospital, Lahore from January, 2012 to September, 2015 were included in the study.
Based on histological features, RMS have been divided into four main classes, embryonal RMS, alveolar RMS pleomorphic RMS and un-differentiated type5,6.
Parotid Submandibular Palate n % n % n % Benign tumors Pleomorphic adenoma 48 69.
5) Performing enucleation, instead of superficial parotidectomy, is the most common cause of recurrence of parotid pleomorphic adenoma.
Clinically pleomorphic adenoma presents as a slow-growing, asymptomatic, unilateral firm mass that may become large if is untreated.
Our case was misdiagnosed as pleomorphic adenoma by FNAC.
The terms of malignant giant cell tumours of soft tissues, giant cell sarcoma, giant cell undifferentiated pleomorphic sarcoma and malignant osteoclastoma are synonyms used for this variant.