Types of Cancer

Overview - Types of Cancer

The following facts and cancer types has been provided by www.mdanderson.org
For additional information please visit their site.

Breast cancer is the most common cancer in women and is second only to lung cancer as the leading cause of cancer deaths among women in the United States. It affects one of every eight American women.

The Center for Disease Control estimates that more than 192,370 women are diagnosed with breast cancer each year, and the number of new cases has declined over the past decade. More than 40,000 women lose their lives to this disease annually.

Men can develop breast cancer, but it happens much less often than in women. Nearly 2,000 men are diagnosed with breast cancer each year.

There are two main types of breast cancer. Breast tumors may have a single type of cancer, a combination of types, or a mixture of invasive and noninvasive (in situ) cancer.
Ductal carcinoma (cancer) is the most common form of breast cancer. Tumors form in the cells of the milk ducts, which carry milk to the nipples. Ductal carcinoma can be invasive with the potential to spread or non-invasive (also called ductal carcinoma in situ or DCIS). About one in five new breast cancer cases are DCIS. The chance for successful treatment of DCIS usually is very high.

Lobular carcinoma (cancer) occurs in the lobules, which are the milk-producing glands. Lobular breast cancer can be non-invasive (in situ or LCIS, also called lobular neoplasia) or invasive (have a tendency to spread). About one in 10 breast cancer cases are invasive lobular cancer.

Less common types of breast cancer
Inflammatory breast cancer (IBC) is a rare, aggressive form of breast cancer that affects the dermal lymphatic system. Rather than forming a lump, IBC tumors grow in flat sheets that cannot be felt in a breast exam. Read more about IBC

Triple-negative breast cancer is usually an invasive ductal carcinoma with cells that lack estrogen and progesterone receptors and do not have an excess of HER2 protein on their surfaces. These types of breast cancers tend to spread more quickly and do not respond to hormone therapy or drugs that target HER2.

Recurrent breast cancer is cancer that has returned after being undetected for a time. It can occur in the remaining breast tissue or at other sites such as the lungs, liver, bones or brain. Even though these tumors are in new locations, they still are called breast cancer.

The American Cancer Society estimates that more than 12,000 women are diagnosed with invasive cervical cancer (cancer that has spread outside the cervix) each year. It is one of the main cancers of the female reproductive organs.

The cervix is in the bottom part of the uterus (or womb, where a baby grows). It joins the uterus to the vagina (birth canal).

Most women who develop cervical cancer are between 20 and 50 years old. It used to be one of the main causes of death from cancer in the United States, but the widespread use of the Pap test has helped doctors find cervical cancer in the early stages. Cervical cancer often can be treated successfully when it is caught and treated early.

Before cervical cancer appears, the cells of the cervix go through precancerous changes, known as dysplasia. Usually this is a slow process that develops over many years.An annual Pap test looks for these changes. If precancerous cells are found, they often can be removed.

Most cases of cervical cancer are caused by infection with human papillomavirus (HPV), which usually is passed from person to person by sexual contact. The American Cancer Society says about 75% of men and women who have had sex will be exposed to HPV at some point.

In most people, the immune system clears the virus before it is detected or causes cells to change. However, in a small percentage of people the virus will remain and cause cell changes that may develop into cancer.

Cervical cancer is usually one of the following types, which are named for the type of cell where they develop. The most common types of cervical cancer are:
Squamous cell carcinoma (cancer): This is the main type of cervical cancer and is found in 80% to 90% of cases. It develops in the lining of the cervix.

Adenocarcinoma develops in gland cells that produce cervical mucus. About 10% to 20% of cervical cancers are adenocarcinomas.

Mixed carcinoma (cancer): Occasionally, cervical cancer has features of squamous cell carcinoma and adenocarcinoma.

Each year, about 22,000 women in the United States are diagnosed with ovarian cancer. While it is the ninth most common cancer (other than skin cancer) in women, ovarian cancer is the fifth high cause of cancer death in women. Most women who develop ovarian cancer are older than 60. It is found more often in white than African-American women.The symptoms of ovarian cancer often are vague or like other conditions. This may make it hard to diagnose. It often has spread to other parts of the body when it is found.

Over the past 20 years, the five-year survival rate for ovarian cancer has improved a lot. Ovarian cancer starts in the ovaries, which are part of a woman’s reproductive system. One ovary is on each side of the uterus (womb). They are oval and produce eggs (ova) that travel through the Fallopian tubes to the uterus. The eggs may be fertilized by sperm and grow into a fetus. Ovaries also make the hormones estrogen and progesterone.

Some tumors found in the ovaries are benign (not cancer) and do not spread beyond the ovary. Others are malignant (cancer) and can spread to other parts of the body.
There are many types of ovarian cancer. Some types of ovarian cancer are extremely rare and require specialized treatment.

The main three types, which are listed below, are named for the cells where they start.
Epithelial: About 90% of ovarian cancers start in the epithelium tissue, which is the lining on the outside of the ovary. This type of ovarian cancer is divided into serous, mucinous, endometrioid, clear cell, transitional and undifferentiated types. The risk of epithelial ovarian cancer increases with age, especially after the age of 50.
Germ cell: Germ cell tumors account for about 5% of ovarian cancers. They begin in the egg-producing cells. This type of ovarian cancer can occur in women of any age, but about 80% are found in women under the age of 30. The main subtypes are teratoma, dysgerminoma, endodermal sinus tumor and choriocarcinoma.
Sex cord stromal: These tumors, about 5% of ovarian cancers, grow in the connective tissue that holds the ovary together and makes estrogen and progesterone. Most are found in older women, but sometimes they occur in girls.  Sex cord stromal tumors usually do not spread as fast as other ovarian tumors. Sub-types include granulosa, granulosa-theca and Sertoli-Leydig cell tumors.

Primary peritoneal carcinoma is a rare cancer. It has cells like those on the outside of the ovaries, but it starts in the lining of the pelvis and abdomen. Women can get this type of cancer even after their ovaries have been removed. Symptoms and treatment are similar to ovarian cancer.

Uterine cancer, or cancer of the uterus (womb), also may be called endometrial cancer. It is the:
• Fourth most common cancer in women
• Most common cancer of women’s reproductive organs

Each year, more than 40,000 women in the United States are diagnosed with uterine cancer. The average age for diagnosis of uterine cancer is 60. However, the number of younger women with uterine cancer is going up. Of uterine cancers, about:
• 25% are found before women go through menopause
• 5% are found before women are 40 years old

Early Diagnosis is Key
Most uterine cancers develop over a period of years. They may start as less serious problems such as endometrial hyperplasia, which is an overgrowth of cells in the lining of the uterus.  Fortunately, many uterine cancers are found early because of warning signs such as abnormal or postmenopausal bleeding. If uterine cancer is found in the earliest stages, it often can be treated successfully.

Uterus Plays a Part in Reproduction
The uterus is where a fetus grows when a woman is pregnant. It is hollow and pear shaped with two main parts:
• The cervix, which is the bottom part and extends into the vagina (the birth canal)
• The body of the uterus is the upper part. It also may be called the corpus. It has two main parts:
– Muscle wall, which contracts when a woman has a baby
- Inner lining (endometrium)
When a woman menstruates (has a period), the endometrium becomes thicker. If she does not become pregnant, the new endometrial tissue goes out of the body as menstrual flow (blood). This happens about every month until a woman stops having periods. When a woman stops having periods it is called menopause (change of life).

There are two types of uterine cancer.
Endometrial cancer: Almost all uterine cancers start in the lining of the uterus (endometrium). The two main types of endometrial cancer are:
- Endometroid adenocarcinoma: This accounts for most cases of endometrium cancer.
- Uterine carcinosarcoma: The cancer cells look like endometrium cancer and sarcoma.

Uterine sarcomas: These are less common types of uterine cancer and start in the muscle wall of the uterus.

According to the American Cancer Society, only about 2,300 women are diagnosed with vaginal cancer each year in the United States. This represents about 1% of cancers of the reproductive system in women.

The vagina sometimes is called the birth canal, because a baby passes through it during the last part of birth. It is a 3- to 4-inch tube that goes from the cervix (bottom section of the uterus or womb) to the vulva (the outside part of female genitals).

The types of vaginal cancer are classified by the type of cell in which they begin.

Squamous cell carcinoma (cancer): About 75% of vaginal cancers are squamous cell cancers, which start in the vagina lining. These cancers develop slowly, sometimes over many years. Often they begin as vaginal intraepithelial neoplasia (VAIN), which is a precancerous condition. VAIN is found most often in women who have had hysterectomies (removal of the uterus), cervical cancer or cervical precancer.

Adenocarcinoma: This type of cancer makes up about 15% of vaginal cancers. It starts in the gland cells of the vagina and is most often found in women over 50. A subtype called clear cell adenocarcinoma is found in younger women whose mothers took the drug DES when they were pregnant.

Melanoma: Fewer than 10% of vaginal cancers are melanomas, which start in the cells that give the skin color.

Sarcoma: About 4% of vaginal cancers are sarcomas, which start within the wall of the vagina. The most common type is rhabdomyosarcoma, which usually is found in children.

Sometimes cancer that begins in other parts of the body spreads (metastasizes) to the vagina. When this happens, the cancer is named for the part of the body where it started. Cancer of the cervix and vagina is called cervical cancer. Cancer of the vulva and vagina is called vulvar cancer.

Vulvar cancer is rare. According to the American Cancer Society, about 4,000 women in the United States are diagnosed with it each year. This accounts for fewer than 1% of cancers in women overall and about 4% of cancers of the female reproductive organs. Vulvar cancer usually grows slowly and may begin as precancerous changes that can be treated before they become cancer.  The vulva, which is part of a woman’s genitals, is at the opening of the vagina (birth canal). It includes the following main parts:
• Opening of the vagina
• Bartholin glands, which help lubricate the vagina during sex. One is on each side of the opening of the vagina.
• Two skin folds around the opening of the vagina:
- Outer lips (labia majora), which are larger and have hair
- Inner lips (labia minora), which are small and do not have hair
• Clitoris, which helps a woman feel sexual stimulation

Vulvar cancer types are named after the cells in which they begin. The main types of vulvar cancer are:
• Squamous cell, which is a wart-like growth. Verrucous vulvar cancer is a subtype. This cancer often can be treated successfully. It is the main type of vulvar cancer.
• Adenocarcinoma usually starts in the Bartholin glands or sweat glands in the vulva. These make up about 8% of vulvar cancers. Paget disease of the vulva is a type of adenocarcinoma in which the cancer cells are in the top layer of skin.
• Melanoma is a skin cancer that starts in cells that make pigment.
• Sarcomas may be found in children as well as adults. These rare types of vulvar cancer start in the muscles or bones. Fatigue is the most common side effect of cancer treatment.