With regard to staging, carcinoma in situ is considered stage 0 cancer.
Roughly 85 percent of cancers are carcinomas.
Carcinoma in situ can be further defined by the tissue punch in in which cancer is beginning.
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Some physicians classify carcinoma in situ as non-invasive cancer and others may prefer calling it pre-cancer.
One of these is dysplasia.
The term precancerous cells may also be used to describe cells on this continuum between normal and cancer cells.
These terms are also used in different ways depending on the sample analyzed.
With cervical dysplasia, a biopsy is required before the diagnosis of CIS is made.
Carcinoma in situ is referred to as stage 0 cancer.
At this stage, cancer is considered non-invasive.
Some people are comfortable observing an abnormality whereas others prefer that anything which could become cancer be removed.
Other treatments may also be used for carcinoma in situ in other regions of the body.
A Word From Verywell
Being told you have carcinoma in situ can be very frightening.
Frequently Asked Questions
Often, it has no symptoms.
Carcinoma in situ, or CIS, is usually not considered cancer.
There are situations in which carcinoma in situ can be completely removed.
The insight from population incidence and mortality.J Natl Cancer Inst Monographs.
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National Cancer Institute.SEER Training: Code 0: In Situ.
Centers for Disease Prevention and Control.Cancer Screening Tests.
Barrio AV, Van zee KJ.Controversies in the Treatment of Ductal Carcinoma in Situ.Annu Rev Med.
Breastcancer.org.Ductal Carcinoma In Situ (DCIS).
National Cancer Institute.Cancer Staging.
National Cancer Institute.Skin Cancer Treatment (PDQ)Patient Version.
Merrill, A., Esserman, L., and M. Morrow.Ductal Carcinoma In Situ.The New England Journal of Medicine.
