In cancer cells, the mitotic index may be elevated compared to normal growth of tissues or cellular repair of the site of an injury. The mitotic index is therefore an important prognostic factor predicting both overall survival and response to chemotherapy in most types of cancer. It may lose much of its predictive value for elderly populations.
Why is the mitotic index important in cancer?
In cancer cells, the mitotic index may be elevated compared to normal growth of tissues or cellular repair of the site of an injury. The mitotic index is therefore an important prognostic factor predicting both overall survival and response to chemotherapy in most types of cancer.
What is a typical figure of mitotic index?
The mitotic index is the number of cells undergoing mitosis divided by the number of cells not undergoing mitosis. A typical figure of mitotic index includes statements like "10 mitotic figures are noted per 10 high power fields" followed by "4 mitotic figures noted per 50 high power fields.".
What is a good mitotic index for mast cell tumors?
Well, generally, a lower mitotic index is better. Fewer dividing cells = a less aggressive cancer. For grade 2 mast cell tumors, the magical number to hope for is a mitotic index of 5 or less. These dogs, with conventional care alone, have a median survival time of 70 months, or nearly six years.
What does a high mitotic index mean for dogs?
The higher the number, the higher the mitotic index and the more aggressive the tumor. If you think about it, this will make sense. The more cancer cells divide, the faster they replicate themselves, the bigger the tumor, and the bigger the problem for your dog. More cell division, faster growth, higher mitotic index.
How is mitotic index used in cancer treatment?
In cancer cells, the mitotic index may be elevated compared to normal growth of tissues or cellular repair of the site of an injury. The mitotic index is therefore an important prognostic factor predicting both overall survival and response to chemotherapy in most types of cancer.
What is mitotic index in cancer?
Listen to pronunciation. (my-TAH-tik IN-dex) In a population of cells, the ratio of the number of cells undergoing mitosis (cell division) to the number of cells not undergoing mitosis.
What is mitotic index and why is it used?
The mitotic index (percentage of cells in mitosis at any time) provides a measure of the capacity of cells to divide and of the rate of cell division. It is used to identify the sites of growth within a tissue and to determine which cell types are dividing.
How is mitotic index used in medicine?
The mitotic index is used for tumor grading of breast and ovarian cancers [8,9]. In addition, mitotic index has been incorporated in the American Joint Committee on Cancer (AJCC) seventh tumor staging system for malignant melanoma, gastrointestinal tumor, and neuroendocrine tumors of the gastrointestinal tract [10].
How is mitotic index used in biopsies?
In patients with malignant melanoma, mitotic activity along with other histopathological characteristics can indicate the depth of tumor invasion. Therefore, in incisional biopsies of melanoma, where actual depth of the tumor cannot be measured, mitotic activity might be used to roughly estimate the depth of invasion.
How do you get the mitotic index?
0:103:171.6 Skill: Determination of mitotic index from a micrograph - YouTubeYouTubeStart of suggested clipEnd of suggested clipIn order to calculate the mitotic index we count the number of cells that are in mitosis divided. ByMoreIn order to calculate the mitotic index we count the number of cells that are in mitosis divided. By the total number of cells in the micrograph. And multiply by 100.
How is the mitotic index used in diagnosis and treatment?
An elevated mitotic index indicates more cells are dividing and is an important prognostic factor predicting both overall survival and response to chemotherapy in most cancer types.
What is mitotic index a level biology?
The mitotic index is the ratio between the number of cells in mitosis and the total number of cells.
What is mitotic rate and how is it used to determine prognosis?
To find the mitotic rate, the number of cells dividing in a certain amount of cancer tissue is counted. Mitotic rate is used to help find the stage of melanoma (a type of skin cancer) and other types of cancer. Higher mitotic rates are linked with lower survival rates.
What affects the mitotic index?
The relative change in the duration of mitosis and of interphase are shown to differ with change in temperature. This difference in temperature response between these parameters results in differences in the Mitotic Index at the different temperatures.
What is the meaning of mitotic?
: of, relating to, involving, or occurring by cellular mitosis mitotic cell division mitotic recombination Microtubules move material through the cell and, in particular, form an important component of the mitotic spindle, which is a structure that separates the duplicated sets of chromosomes in the course of cell ...
What is considered a normal mitotic index?
Labelling and mitotic indices were studied in the epidermis of twenty-eight young men. A mean labelling index of 5.5% was found from the whole study and a mean mitotic index of 0.06%. Mitotic index particularly was extremely variable; indices between 0.002 and 0.438% were found in individual biopsies.
What is the purpose of mitotic index?
Purpose. The mitotic index is a measure of cellular proliferation. It is defined as the percentage of cells undergoing mitosis in a given population of cells. Mitosis is the division of somatic cells into two daughter cells. Durations of the cell cycle and mitosis vary in different cell types.
Why is the mitotic index important?
The mitotic index is therefore an important prognostic factor predicting both overall survival and response to chemotherapy in most types of cancer.
How to get mitotic index?
To get the mitotic index, the pathologist looks at a slide with a very thin slice of your dog’s tumor tissue on it. The tissue has been stained so it is colored and they can easily see which cells are dividing (in mitosis). They simply count the numbers of these cells to get the mitotic index.
What is the mitotic index of a grade 2 mast cell tumor?
If you have a grade 2 mast cell tumor with a mitotic index of <5, your minimum treatment surgery with a wide excision of 2 to 3 centimeters.
How long do dogs live with a grade 2 mast cell tumor?
Unfortunately, dogs with grade 2 mast cell tumors with a mitotic index of greater than 5 have a dramatically shorter median life expectancy of only 5 months. This is quite a dramatic difference. Here is the abstract to show you where I am getting this information.
How long does a mast cell tumor last in dogs?
These dogs, with conventional care alone, have a median survival time of 70 months, or nearly six years. That’s a nice long median survival time.
What is the grade of mast cell tumor?
In mast cell tumors, the grade is usually broken down into three levels, with grade 1 being the lowest and grade 3 being the highest and most aggressive. (There is also a newer, 2-tiered system of grading mast cell tumors that may be available to your oncologist and may be useful in real “gray zone” cases.)
What is a high grade cancer?
As you may already know, the “ grade ” is a measure of how aggressive a cancer is. When we say a cancer is a “high grade malignancy” we mean it is hard to cure. A “low grade” growth is easier to cure as a generality (but not always), usually by surgical removal.
Can a grade 2 mast cell tumor be benign?
Grade 2 mast cell tumors can behave aggressively (like grade 3’s) or more like benign growths (grade 1’s). It’s grade 2 mast cell tumors that can most benefit from a mitotic index measurement. The number will be on your biopsy report.