How long does it take for breast cancer to grow?
Like a lot of cancers, breast cancer grows by simple cell division. It begins as one malignant cell, which then divides and becomes two bad cells, which divide again and become four bad cells, and so on. Breast cancer has to divide 30 times (from 1 cell to 1073741824 cells) before it can be felt. Up to the 28th cell division, neither you nor your doctor can detect it by hand.
With most breast cancers, each division takes one to two months, so by the time you can feel a cancerous lump, the cancer has been in your body for two and a half to five years. It can certainly seem like a lump appeared out of nowhere – especially if you or your doctor have recently examined your breasts and not felt anything suspicious – but in reality, the cancer has simply doubled that one last time necessary to be noticeable. By the time you can feel it, a breast tumor is usually a little more than one-half inch in size – about a third the size of a golf ball. It has also been in your body long enough to have had a chance to spread.
This sounds scary, but what it really shows the importance of self exams and regular mammograms. Mammograms can usually detect breast cancer when it’s about one-quarter inch in size or smaller – a year or more before it would be detectable by hand. Mammograms also make possible the early diagnosis of some pre-cancerous conditions and early-stage cancers that appear as tiny calcifications (microcalcifications) on mammography, but aren’t detectable by physical examination.
It’s important to realize that there are two types of mammograms:
A screening mammogram is performed in cases where there isn’t any known problem. This type of mammogram is used for annual exams.
A diagnostic mammogram is performed when there is a known problem that requires careful evaluation. Diagnostic mammograms provide much more extensive images than screening mammograms, such as views from additional angles and compression, or blow-up, views. Often an ultrasound will be done in addition to the mammogram if there is a palpable lump. Make sure you receive a diagnostic mammogram if you’ve found a lump.
It is very hard to estimate how a person’s breast cancer will change over the course of a year. Different types of breast cancer grow at different rates, and many factors affect its growth and chances of spreading.
Cancer occurs due to mutations in our cells. Mutations do not follow normal, predictable patterns of cell division, so it is difficult to predict the progression.
Tumors appear when damaged cells replicate over and over to form a clump of abnormal cells. Breast cancer cells can break off and move through the lymph or blood vessels to other areas of the body.
If breast cancer cells begin to grow in another body part, this is called metastasis. Breast cancer is most likely to metastasize to the lymph nodes, lungs, and bones.
Regardless of the location of the new tumor, doctors still consider it to be breast cancer.
Breast cancer growth and its chances of spreading depend on the following:
Breast cancer can be invasive or noninvasive:
Noninvasive breast cancer will not spread beyond the ducts or lobules.
Invasive breast cancer can spread to the surrounding connective tissue, the lymph nodes, and other areas of the body.
Grade (1–3) A doctor will grade breast cancer (1–3) based on how much the cancer cells look like normal breast cells:
grade 1 is a slower-growing cancer
grade 3 is a faster-growing cancer
A higher grade means that a cancer is more likely to grow faster and to spread to other areas of the breast or body.
Stage (0–4) Healthcare professionals describe the extent of breast cancer progression in stages. This information is incredibly important when making decisions regarding treatment.
The stages of breast cancer are as follows:
Stage 0. Doctors consider breast cancer at this stage noninvasive, and it is only present in the ducts or the lobules. Ductal carcinoma in situ is a form of stage 0 breast cancer.
Stage 1. Breast cancer at this stage is invasive, but it remains small and near the primary site. Stage 1A involves tumors that are 2 centimeters or smaller and have not reached the lymph nodes. At stage 1B, the cancer has reached the lymph nodes.
Stage 2. Stage 2 breast cancer is invasive, tumors may be larger than in stage 1, and the cancer may have spread to the lymph nodes.
Stage 3. Stage 3 breast cancer is invasive, tumors may be larger, and cancer has spread to the lymph nodes, possibly to several. Breast cancer at this stage has not spread to other organs.
Stage 4. Breast cancer has developed in other areas of the body outside the breast and lymph nodes, often in the bones, lungs, brain, or liver. Treatment at this stage focuses on controlling the cancer and preventing it from spreading any farther.
Cancer that has already spread to other areas of the body, or stage 4 cancer, is more likely to spread further.
Although it is difficult to assess the progress of cancer over the course of 1 year, the American Cancer Society provide estimates about the 5-year survival rates for people at different stages of breast cancer.
The 5-year survival rate refers to the number of people who will live for 5 years after finding out that they have breast cancer:
a. close to 100 percent for stages 0 and 1
b. 93 percent for stage 2
c. 72 percent for stage 3
d. 22 percent for stage 4
These figures are population estimates. Each person’s individual survival rate varies depending on a wide range of factors.
Growth or spread within a year will often depend on personal factors, including:
1. age at diagnosis
2. hormone status, such as pre- or postmenopause
3. family history of breast cancer
4. exposure to alcohol, cigarettes, or pollution
5. previous history of cancer
A doctor may also take how a person responds to previous or current treatment into account when working out the likely change or progression of cancer.
The speed at which a cancer progresses depends on the growth rate of the cancer cells. It is hard to estimate cancer growth because not all cancer cells multiply and divide at the same speed.
In most cases, breast cancer initially develops in either the milk ducts or the lobules, which are the glands that produce milk, before expanding into the breast tissue.
Breast cancer that develops in ducts or lobules can spread to the connective tissue. From there, it can spread to the surrounding lymph nodes.
Once in the lymph nodes, the cancer cells can enter the lymphatic system or the bloodstream, where they can move to other areas of the body.
One recent study looked at the growth rate of invasive breast cancer tumors. The researchers reported that certain types of breast cancer, such as triple-negative breast cancer and HER2-positive breast cancer, grew at fast rates.
Some signs and symptoms of breast cancer include:
1. a lump or mass in the breast tissue
2. pain, swelling, or redness on any part of the breast
3. dimpling of the skin covering the breast
4. unusual nipple discharge
5. flaking skin on or near the nipple
6. change in the shape or size of the breast
If you find a lump, see your doctor as soon as possible. Don’t settle for just a mammogram if the mammogram doesn’t find anything. The next step should be a screening ultrasound, and if those results are indeterminate you need to get a biopsy. Ask you doctor for these tests if he or she doesn’t schedule them.