Precancer


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Related to Precancer: precancerous, precancerous lesion

Precancer

 

pathological changes that precede the development of a malignant tumor.

The concept of “precancer” was first formulated with regard to skin cancer, which is the most accessible to clinical observation. Later, precancer was diagnosed in the lower lip, breasts, cervix of the uterus, and stomach. Research in experimental oncology has demonstrated that precancerous conditions differing in clinical manifestations represent the same basic pathological process with the same definite pattern.

There are three stages of precancer generally distinguished in Soviet oncology. In the stage of uneven diffuse hyperplasia, the tissue retains its normal structure, but the number of its structural elements, such as cells and fibers, increases. In the stage of focal proliferation, the total mass of multiplying cells contains areas, or foci, in which the cells divide with unusual rapidity. In the comparatively benign tumor stage the foci of multiplying cells steadily cease to resemble the original tissue and become increasingly isolated but do not exhibit a tendency toward invasive growth—that is, growth into and destruction of healthy tissue. The first stage is not yet precancer in the strict sense of the word. The second stage is the most characteristic stage of a precancer. The third stage is not essential, since the cancer can bypass it and continue developing. A precancer can regress or cease developing for a long time.

REFERENCE

Shabad, L. M. Predrak v eksperimental’no-morfologicheskom aspekte. Moscow, 1967.
References in periodicals archive ?
Women over age 65 years who have been screened regularly with normal results do not require screening, but those over age 65 years who are diagnosed with cervical precancer should continue to be screened, the ACS guidelines say.
The investigators graded anal tissue and cells by systems used for cervical lesion staging, ranging from healthy, to various precancer stages, to cancer (Table 1).
All publicly funded care Title X centers From contraceptive services Unintended pregnancies 2,229,900 1,181,500 Unplanned births 1,105,800 585,900 Abortions 760,800 403,100 Closely spaced births 287,500 152,310 Preterm/LBW births 164,190 87,110 From STI prevention services Chlamydia infections 99,100 53,450 Gonorrhea infections 16,240 8,810 HIV infections 410 250 PID cases 13,170 6,920 Ectopic pregnancies 1,130 590 Infertility cases 2,210 1,160 From cervical cancer prevention services Abnormal cervical cell cases 7,500 3,970 Precancer cases 1,500 790 Cervical cancer cases 3,680 1,940 Cervical cancer deaths 2,100 1,110 Other HPV-attributable cancer 44 24 cases Notes: LBW=low-birth-weight.
The clinical trial, called the DeeP-C study, included 10,000 patients and was designed to determine how well Cologuard detects precancer and cancer.
If more oral spots are tested to rule out the presence of precancer or cancer, the incidence rate of this disease would drop dramatically.
One technology, known as fluorescence lifetime imaging (FLIM), enables Maitland and Jo to image large areas of oral tissue with ultraviolet light in a manner that shows signs of the molecular changes associated with precancer and cancer, revealing potential trouble areas.
Clinical studies over the years have proved that detecting precancer has caused mortality rates to drop.
Medicis products fight acne, precancer skin growths and skin-related viruses.
The precancer risk of betel quid chewing, tobacco use and alcohol consumption in oral leukoplakia and oral submucous fibrosis in southern Taiwan.
Definition of leukoplakia and related lesions: An aid to studies on oral precancer.
Preventive strikes; women, precancer, and prophylactic surgery.
Researchers from the University of California, San Francisco, tracked nearly 1,200 women who were diagnosed with ductal carcinoma in situ, or DCIS, which is often referred to as precancer because the risky cells haven't moved outside the milk duct.