Is carcinoma in situ neoplasia or dysplasia?
A carcinoma (car-suh-no-mah) is a cancer of the skin cells. In situ (in-SIGH-too) is a term from the Latin that translates to 'at this site' or 'point of origin'. Therefore, carcinoma in situ (CIS) is cancer contained to the site of origin. It is no longer dysplasia/neoplasia. It is cancer, but it is non-invasive cancer (also known as cancer, stage 0) and is cancer detected at its earliest point before it invades surrounding tissue.
Intraepithelial Neoplasia (Intra epee-thel-eee-ell knee-o-PLAY-zhuh) simply translated means new (neo) growth of cells that are not normal (plasia) in the outer layer (named 'epithelial') of the skin cells and contained to this area (intra). These pre-cancerous cells form a lesion also called dysplasia (dis-PLAY-zhuh). Dysplasia is also known as 'squamous intraepithelial lesions' (SIL), so-named because it occurs within the epithelial layer (outer layer) of skin cells (named 'squamous'). These abnormal cell conditions are commonly described as Intraepithelial Neoplasia. Technically, neoplasia is new growth (that is not normal) and dysplasia is the existence of that new growth, which manifests itself as a lesion. The two terms are commonly used interchangeably. These (dysplasia, neoplasia, and squamous intraepithelial lesions) are considered a pre-cancerous condition. However, if not treated, they can progress to cancer.
Cancer is the uncontrolled growth of non-normal cells. The abnormal cells grow, and in doing so, destroy healthy cells. At some point, the cancer cells create a situation where the body can no longer function. With dysplasia, the abnormal cells are not as destructive. However, if the abnormal cells start to grow uncontrollably into the deeper layers of the skin, then they move from the category of dysplasia into the category of cancer. This growth into the deeper layers constitutes 'invasive' cancer.
The most prevalent of the gynecologic dysplasia conditions are CIN (Cervical Intraepithelial Neoplasia), VIN (Vulvar Intraepithelial Neoplasia), and VaIN (Vaginal Intraepithelial Neoplasia). In addition, there are PaIN (Perianal [peri means around] Intraepithelial Neoplasia) and AIN (Anal Intraepithelial Neoplasia) in the gynecologic category.
There are three categories of dysplasia - Stage I, Stage II, and Stage III. Stage I may be "fixed" by the body's immune system, so some doctors employ a 'wait and watch' period. Stage II and III should be treated medically. The line between Stage III and carcinoma in situ is a little blurry because sometimes it is referred to as Stage III/carcinoma in situ.
The cause of dysplasia has been linked to the human papillomavirus (HPV). HPV is a family of over 100 identified strains of the virus called human papillomavirus (this is one word). A papilloma is a wart-like growth. HPV is responsible for the common warts found on hands and feet, such as plantar warts. Of the 100 identified strains, approximately 30 are sexually transmitted.
Of those 30 about half are considered high risk for causing cancer and do not cause warts. They have been linked to, in excess of, 90% of all Cervical, Vaginal, Vulvar, Perianal, Anal cancers (Colon, Colorectal, and Rectal cancers are on the inside of the body; Anal cancer is exterior), and dysplasia. As well, there is a link to some oral cancers and cancers of the neck and throat. The Pap Test can screen a woman for HPV of the cervix. There is no screening test for men and a man (or a woman) can have HPV, pass it on to partners, and never know it is there. The wearing of a condom does not protect either partner (save reducing the risk for cervical infection) because HPV is a skin-to-skin virus which can be transferred through skin-to-skin contact even without sexual intercourse.
Of the low risk half, they cause the STD that can manifest itself as warts on the external genitalia of both males and females.
There is no cure for HPV and it can lay dormant in the system for decades (or forever if the immune system is not compromised) before becoming active. It is a lot like Russian Roulette. This is a very strong argument for the new HPV vaccine, Gardasil. The window of time for receiving the vaccine is very small, but risks of contracting HPV are vast and lifelong.
The American Cancer Society (ACS) [www.cancer.org] compiles one of the most comprehensive lists of projected cancer cases, by category, in its annual report, which is called Cancer Facts and Figures [.pdf from its main page]. However, it does not include cases of non-invasive cancers (cancer, stage 0 aka CIS) [except for urinary bladder, pg1] as is stated in the fine print.
Unless one is terminology savvy, the distinction between invasive cancers and non-invasive cancers can be easily overlooked. The ACS estimates, in its annual report, that there will be 11,270 cases of cervical cancer in 2009. These are cases determined to be stage 1 or greater. There are a number of researchers that believe that non-invasive cases of cervical cancer are 4 times greater than invasive cases, a fact acknowledged on the ACS' Cervical Cancer page. This would mean that, in actuality, 56,350 cases of cervical cancer will be diagnosed in 2009. Let's break down the math: 11,270 times 4 equals 45,080 (total non-invasive cases) plus 11, 270 (invasive cases) equals 56,350.
This is a huge difference, and at first blush, would seem to be a glaring oversight. However, we must consider that of all the cancers that afflict humankind, cervical cancer is one (perhaps, the only one) that has a commonly used, accurate, affordable screening test available to any woman at any time. That test is the Pap test (also known as the Pap Smear). It is so accurate that it detects the cell changes long before they get to cancer (this would be the dysplasias). As with any cancer, early detection is a great advantage. Early detection, coupled with early treatment, saves 45,080 women this year from being included in the ACS' annual report.
It seems logical and is understandable, that in the interest of fairness, accuracy, and uniformity, the ACS uses Stage I of all the cancers as the beginning point for its reporting. However, the reader should be aware of this criterion. All cancers have a beginning - a point of origin where they would be pronounced Stage 0/CIS if they could be detected.
Sadly, the pap test is only helpful if a woman chooses to avail herself of it. In 2001, Cooper Surgical, Inc (Cooper, 2001) reported that 50 million pap tests are done each year. The U.S. Census Bureau (U.S. Population, 2000) reported that, as of 2000, there were 108, 369,877 adult women in the U.S. That equates into less than half of the adult female population getting a pap test each year. According to the rules of mathematical probability, that indicates that the known numbers for invasive cervical cancer, CIS, and dysplasia could, actually, be double. As well, the numbers for the other gynecologic conditions could be double what is actually known and reported. For cervical cancer (not dysplasia) of all stages, the number of new cases could be 112,700 (56,350 times 2) in 2009.
Be sure to have your annual check-ups and report any abnormalities to your doctor that occur between visits.
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Cooper (2001). The Cooper Companies press release. Cooper Surgical, Inc. Retrieved August 10, 2005 from http://www.coopersurgical.com/csweb/press_release.as p?id=37
U.S. Population (2000). Retrieved July 18, 2005 from http://factfinder.census.gov/home/saff/main.html?_la ng=en