Progression of breast cancer: Stages
If a biopsy confirms that breast cancer is indeed the diagnosis, the staging process begins.
The stage is really the ‘extent‘ of the breast cancer, and in order to begin treatments and choose the best treatment methods, it is necessary to ‘stage’ the breast cancer in term of how far it may have progressed.
Breast cancer progresses in relatively predictable and consistent ways, so it is possible to categorize a breast cancer in terms of a “stage” based on this progression.
There are basically five ‘stages’ applied to breast cancer, with some subcategories (even though they actually are numbered from ‘zero’ through ‘four’).
Breast cancer progression tends to be consistent and predictable
There are many ways that breast cancer can develop, but most of the time it starts in the breast ducts.
While still confined to the breast ducts breast cancer is often referred to as ductal carcinoma in situ, or DCIS. If breast cancer is detected while still at this in-situ stage, the chance of survival is close to 100%.
As the cancer moves into the breast duct wall and finally begins to effect the surrounding breast tissue, it is called infiltrative or invasive breast cancer.
Left untreated, breast cancer will usually spread to other areas of the body (metastasize), and the first place it usually spreads is to the lymph nodes in the underam area (the axilla). Once the cancer has entered the lymphatic system, it can and usually does spread to other areas of the body. Sometimes this is called ‘distant metastasis’.
Not all breast cancers spread first to the axillary lymph nodes and then to the rest of the body. If the breast tumor is located near the nipple, the cancer may spread first to the ‘internal mammary nodes’ beneath the sternum. And in some cases the breast cancer can spread via the bloodstream without involving the lymphatic system.
Staging involves bone scans, lymph node evaluation, and possibly a CT scan or other scans
Breast cancer staging almost always involves a bone scan, as breast cancer is highly prone to metastasize to the bones. During this test, a small amount of a radioactive substance is injected into the blood stream, where it eventually collects in the bones. A radiation scanner is then able to detect accumulations of tracer substance in the bones..
If a breast cancer spreads beyond the breast, 25% of the time it goes into bones first.
Breast cancer cells seem to prefer to settle into long bones in the arms and legs, as well as those of the ribs, spine, pelvis, and skull are often affected. With an ‘osteolytic‘ metastasis, the cancer kind of ‘eats away’ at the bone, creating ‘holes’.
With an ‘osteoblastic‘ bone metastasis the bone mineral density is actually increased, but this can cause the bones to fracture more easily. This requires a little more explanation. Breast cancer metastases tend to be lytic when they are untreated, and then they become densely sclerotic as they respond to treatment. Even if no treatment is given yet, an osteoblastic metastasis from breast cancer generally indicates that the persons own body is trying to fight the cancer with some success.
A CT scan may also be used to check for metastasis to the the lungs or liver. A CT scan is essentially an X-ray linked to a computer. A contrast dye agent is injected into the blood stream and this makes any cancer spread into the liver and chest easier to see.
About those lymph nodes.
A lymph node biopsy will usually be taken to determine is breast cancer has spread to the axillary lymph nodes. This is not always necessary, however. A lymph node biopsy is not needed, generally for DCIS, but for invasive breast cancer, yes, they do need to check the lymph nodes. Sometimes, a ‘sentinel node biopsy“, is performed rather than a full lymph node excisional biopsy, if the concerns about cancer spread appear to be minimal. Cancer cells tend to appear first in the sentinel node before spreading to the other nodes or other areas of the body.
The original breast tumor is called the ‘primary’ tumor
The original breast cancer site (in the breast) is called the ‘primary‘ tumor, while any metastases are called either secondary tumors, or simply ‘metastatic breast cancer’. Note, when breast cancer spreads to the bones, it is not called ‘bone cancer’. It is called metastatic breast cancer in the bones.
“Metastatic” describes a breast cancer that has already spread to distant areas and organs of the body. A metastatic cancer is the most advanced ‘stage’ of breast cancer, and the most common regions for breast cancer to metastasize are to the bones, and the liver and lungs.
Once breast cancer has reached this most advanced metastatic (systemic) stage, the odds of completely curing the breast cancer are quite low. The treatment of metastatic breast cancer, after a reasonable effort, will often focus on quality of life and relieving symptoms rather than just to extend a lifetime.
Conventional ‘stages’ of breast cancer progression: 0 through IV
As mentioned, there are five basic stages of breast cancer, with a couple of sub-categories. Stage 0 is a bit of an unclear term, and is sometimes used to describe the development of abnormal cells, which are not yet invasive breast cancer. Ductal carcinoma in situ, or DCIS, would be considered stage 0 breast cancer.
Here the malignant cancer cells are present in the lining of the breast duct, but have not yet invaded the surrounding breast tissue or spread beyond the duct. Almost 100% of DCIS is curable, but it does need to be treated.
Early stage breast cancer; stage 1
Stage 1 breast cancer is sometimes referred to as ‘early stage’ breast cancer. There is considerable difference of opinion as to what exactly constitutes and early stage breast cancer and how aggressively it needs to be treated. The standard definition of a stage 1 breast tumor is that a certain amount of breast cancer has invaded beyond the duct lining, but no cancer cells have spread beyond the breast. And, the tumor size is less than 2 cm in diameter. If the breast cancer can be detected and treated before it grows beyond 2cm, the prognosis is very very good.
The average age of diagnosis of a stage 1 breast tumor is about 52 years old. In over 90% of cases, treatment tends to involve breast conservation surgery, and most often followed by radiation therapy.
Previously, most stage 1 breast cancers required lymph node dissection to check for breast cancer spread, usually around 18 nodes were sampled.
This page mentions imaging the axilla. This page shows micrometastases in lymph nodes. These pages mention arm symptoms and lymphedema swelling after armpit surgery, this page mentions the surgeon’s principles of what to do, but it looks like my website is lacking a nice simple page about the lymph node dissection surgery. I tried finding good external pages, but they all seem pretty weak. This one is OK.
Chance of stage 1 cancer, recurrence or spreading.
Local recurrence of stage I breast tumors is estimated at about 3%, and the rate of distance recurrence is about 8%. About 72% of women with stage one breast cancers, properly treated, will have no recurrence of breast cancer over 15 years, and the overall survival rate after 15 years can be estimated at a little above that, around 74%.
These statistics are old. It’s even better nowadays.
Four basic subtypes of stage II breast cancer
There are basically four sub-categories of breast cancer considered as stage II. A breast tumor that is 2cm in diameter or less, but in which the cancer cells have already metastasized to the lymph nodes is considered stage II.
A breast tumor which is larger than 5 cm, but has not yet spread to the lymph nodes is still considered stage II as well.
Breast tumors in between 2cm and 5 cm in diameter are also considered stage 2, whether there is evidence of spread to the lymph nodes or not. There are actually quite a number of specific subcategories and letters and numbers to indicate a more precise description of the breast cancer, too detailed to get into here, but in general a stage II breast cancer is of intermediate size and threatening to spread. Without a doubt, staging for stage II breast cancers requires a thorough investigation of potential metastases.
The average survival rate for stage II breast cancers is about 82% after five years and about 75% after 10 years. The rate of local recurrence is about 16% for stage II breast tumors, and about 16% of stage II breast cancers either have or will develop lymph node metastasis.
These statistics are old. Survival is even better now, compared to when I originally created this page.
A baseline bone scan is unlikely to detect bone metastasis with stage 2 tumors, but they are usually recommended just to be sure.
Incidently, breast conservation therapy is used for stage II breast tumors about 80% of time. Appropriate adjuvant therapy has also shown to increase overall survival of stage II breast cancers. All patients with stage II breast cancer should be given consideration for adjuvant therapy, especially where there are indications of the beginnings of systemic disease (positive lymph nodes) Adjuvant chemotherapy has been shown to increase disease-free interval and overall survival by about 24% and 15% respectively for women with node-positive stage II breast cancer.
Stage III breast cancer; locally advanced
A stage 3 breast cancer is sometimes referred to as a ‘locally advanced’ breast cancer.
Stage III breast cancers are actually a heterogeneous group of cancers, but account for about 7% of all initial breast cancer diagnosis.
Basically, a stage III breast cancer is one in which there is a primary tumor of greater than 5cm in diameter with no apparent metastasis, or, the tumor is between 2cm and 5cm in diameter with evidence of rather significant metastasis.
Another way of looking at it, stage III breast cancers either have a large but ‘operable’ (surgically curable) breast tumor, (stage IIIa), or present with a medium sized breast tumor (2cm to 5cm) which is more difficult to fully treat and cure with surgery alone.
Sometimes large breast cancers invade into muscle or attach to major arteries,veins or nerve trunks, which makes them
impossible to surgically remove “completely”. So for these patients, the treatment usually starts with radiation or chemo to try to shrink it first, to see if it can have surgery later. But even a large (5cm) tumor that hasn’t attached itself onto muscle, can be completely removed if the woman is in fortuitous circumstances. There is no direct relationship between tumor size and whether or not it may be treated surgically or not.
Stage 3 breast cancers which can be completely removed do tend to have a significantly better prognosis than inoperable stage 3 breast cancers. However, some breast tumors, particularly those that are ER positive, respond very well to chemotherapy, so well that they become ‘downstaged’. So it is difficult to predict the overall prognosis for stage 3 breast cancer, as it will very from individual to individual. If the response to chemotherapy is favorable, the overall survival rate can be as high as 60%.
‘Operable’ vs ‘inoperable’ (removable or not) stage III breast cancers
So, there is still a little bit of ambiguity regarding stage 3 breast cancers. A stage IIIA breast cancer is one in which the tumor is no more than 5 centimeters across, but with positive metastasis to the axillary lymph nodes either alone or ‘attached to each other’, or spread to the lymph nodes behind the sternum. (called ‘internal mammary lymph nodes)
The internal mammary nodes are found behind the ribs. Ribs are made of bone, but in the front they turn into cartilage just before they join onto the sternum. Beside the sternum, all the ribs joint onto it with cartilage and each of these cartilage bars from each rib tend to be about 5 cm long. It can be very difficult to remove an internal mammary node. There is an internal mammary artery and vein along with the lymph ducts and other veins. If you want to remove an internal mammary node, the cartilage in front of it needs to be cut out. Cartilage, unfortunately, does not grow back or heal, and this will leave a gap which makes the rib essentially useless. So, it is a judgement call by the surgeon as to whether or not one should attempt a surgical approach to remove internal mammary nodes with positive metastasis, as it is just too damaging to the function of the chest and ribs. However, the internal mammary nodes may be treated very effectively by electron beam radiotherapy, as the electrons penetrate to about the correct depth to reach these internal mammary nodes.
Women with stage IIIa breast cancers tend to be treated with a modified radical mastectomy and locoregional radiotherapy. (locoregional means that the radiation beam is aimed at the location of the tumor, and the surrounding region.) Often, chemotherapy is given as adjuvant therapy, but in some cases pre-operative chemotherapy is also recommended. Breast conservation is generally not a good option with stage IIIa breast cancers.
A stage IIIb breast cancer is one in which the tumor may be of any size but it has grown into the chest wall or the skin of the breast. A stage IIIb designation is also frequently given if there is evidence of either axillary lymph node metastasis or internal mammary node metastasis, presenting in such a way as to suggest that they cannot effectively be removed by surgery.
There is a unique type of breast cancer called ‘inflammatory breast cancer‘, which causes the breast to appear red and swollen. This is because the cancer cells have ‘blocked’ some lymphatic vessels. Inflammatory breast cancers tend to have a poorer prognosis, and are generally staged at IIIb at least.
Stage 3c breast cancers basically involve tumors of any size with significant metastases to the lymph nodes behind the sternum or under the arm, and also above or below the collarbone. The extent and depth of lymph node involvement makes these patients unsuitable candidates for surgical treatment as the primary mode of therapy. Women with stage IIIb and IIIc breast cancers are generally treated with various regimens of chemotherapy.
However, up to 70% of patients with stage III breast cancers treated by chemotherapy remain alive and disease free after 7 years.
Advanced or metastatic breast cancer: stage IV
Stage 4 breast cancers indicate the presence of distant metastasis to other parts of the body, such as the liver or bones.
About 5%-9% of women have a stage IV breast cancer at the time of initial diagnosis.
This number is too high. It’s old information. Breast cancer screening and awareness has been a big improvement. And because this page is old, the statistics on survival are out-of-date also, for instance, the long term survival below, the numbers are better now.
The long term survival rate for stage IV breast cancer tends to be rather low, at between 16% and 20%. However, with strategic and effective combinations of chemotherapy, about 50% of patients with stage IV breast cancer survive disease free after four years.
But there are many serious and personal questions to be asked with stage IV breast cancer. Given that overall survival is less likely, and gains from intensive breast cancer treatment are unfortunately rather modest, one has to give serious consideration to ‘quality of life’ during the course of treatment. This is an individualized and dynamic process between patients and physicians with respect to the expectations for treatment, the status of the disease and patient wishes.
Stage IV breast cancers may be ‘recurrences’ following initial treatment
Up to 10% of intitial breast cancer diagnoses are of the most advanced or metastatic stage, but this number has been significantly reduced with the implementation of widespread breast cancer screening programs.
Metastatic breast cancer can appear to be a rapid deterioration of a disease which has been present for some time, undetected. But metastatic or advanced stage breast cancer can also be the result of a recurrence of breast cancer after a successful initial treatment. Sometimes the terms ‘local’ and ‘regional’ recurrence are used to indicate a return of breast cancer to the original tumor site ( removed by surgery) or elsewhere in the breast or contralateral breast. If the cancer returns in other areas of the body it is sometimes called a ‘distant’ metastasis or distant recurrence.
Stage IV breast cancer involves ‘quality of life’ decisions
Almost 70% of women who eventually succumb to breast cancer (around 80% or higher of all breast cancer patients survive) develop metastasis to the lungs. The third most common site of breast cancer metastasis is to the liver, and about 2/3 of women with advanced stage or metastatic breast cancer will eventually see it spread to the liver. Other, less commonly effected areas of the body are the brain, spinal cord, eyes, and the ovaries. Bone scans, chest Xrays, CAT scans, MRIs, and blood tests may be used to check for metastasis. So, once breast cancer is diagnosed, while in general the outlook is favorable when compared to other types of cancer, it should really be considered a ‘chronic’ condition. But the progression is not going to be the same for everyone, even for patients with similar stages of disease presentation. Breast cancer has been known to return even 20 years after a mastecomy, while in others, the progression and systemic development of disease may be rapid.
still here? What about saying no to treatment?
Anxiety, fear, panic, anger, sadness. If you are in the middle of a combination of all of that, today is not a good day to make important decisions.
And since this page is old and poorly written, don’t bet your life on anything negative on the page.
Here’s my quick ‘imagine a way this all gets better’ line of reasoning, intended to help you. Because treatments are so effective nowadays, and so well organized for a steady flow of patients, the people who treat breast cancer are experienced experts. Give them some trust and time to explain things properly, and accept the treatments. Do one step at a time, one day at a time, and you’ll be amazed at the results.
Add in lots of sleep, good foods, daily exercise, socializing with people, reconnecting with friends and family. Each of these is scientifically proved to improve your own body’s immunologic fight against the cancer.
You’ve invested a lot of time reading a long page, you’re motivated, you’ve learned that treatments are highly effective and smoothly given, and your next step is one step… is it to see a doctor, to agree to a treatment, to get a biopsy, or whatever. One step at a time.
- Iturbe, J., Leone, JP., Zwenger, AO., Lacava, JA., Vallejo, CT., Scuteri, RR., Cabaleiro, SP., Castro, J., Leone, BA. Treatment of stage I breast cancer (T1N0M0): A long-term follow-up study. J Clin Oncol (2008) 26: supplement.
- Dubois JB, Saumon-Reme M, Gary-Bobo J, Pourquier H, Pujol H. Tumorectomy and radiation therapy in early breast cancer: a report on 392 patients. Radiology. (Jun 1990) 175(3):867-71.
- Coleman RE, Rubens RD, Fogelman I. Reappraisal of the baseline bone scan in breast cancer. J Nucl Med. 1988 Jun;29(6):1045-9.
- Yang SH, Yang KH, Li YP, Zhang YC, He XD, Song AL, Tian JH, Jiang L, Bai ZG, He LF, Liu YL, Ma B. Breast conservation therapy for stage I or stage II breast cancer: a meta-analysis of randomized controlled trials. Ann Oncol.(Jun 2008) 19(6):1039-44.
- Gamel, JW., Vogel, RL, Vlagussa, P., Bonadonaa, G.,Parametric survival analysis of adjuvant therapy for stage II breast cancer. Cancer (Nov. 1994) Volume 74, Issue 9, pages 24832490.
- Stephen, FO., Intraarterial induction chemotherapy in locally advanced stage III breast cancer. Cancer (Aug. 1990) Volume 66, Issue 4, pages 645650.
- Rizzo, M., Reisman, N., Gabram, SG., Bumpers, HL., Okoli, J. Brawley, OW., Lund, M. Differences in treatment in stage III breast cancer in African American women. Journal of Clinical Oncology, (2007) ASCO Annual Meeting Proceedings (Post-Meeting Edition). Vol 25, No 18S (June 20 Supplement), 2007: 504
- Stewart, JF., King, RJB., Winter, PJ., Tong, D., Hayward, JL., Rubens, RD. Oestrogen receptors, clinical features and prognosis in stage III breast cancer. European Journal of Cancer and Clinical Oncology ( December 1982) Volume 18, Issue 12, Pages 1315-1320
- Honkoop, AH., Wagstaff, J., Pinedo, HM. Management of Stage III Breast Cancer. Oncology (1998);55:218-227
- Shenkier T, Weir L, Levine M, Olivotto I, Whelan T, Reyno L; Steering Committee on Clinical Practice Guidelines for the Care and Treatment of Breast Cancer. Clinical practice guidelines for the care and treatment of breast cancer: 15. Treatment for women with stage III or locally advanced breast cancer. CMAJ. (march 2004) 170(6):983-94.
- Klefstrom P, Grohn P, Heinonen E, Holsti L, Holsti P. Adjuvant postoperative radiotherapy, chemotherapy, and immunotherapy in stage III breast cancer. II. 5-year results and influence of levamisole. Cancer (1987);60(5):936-42
- Wolff AC, Davidson NE. Primary systemic therapy in operable breast cancer. J Clin Oncol (2000);18(7):1558-69
- Hortobagyi GN, Ames FC, Buzdar AU, Kau SW, McNeese MD, Paulus D, et al. Management of stage III primary breast cancer with primary chemotherapy, surgery, and radiation therapy. Cancer (1988);62(12):2507-16.
- Bidard FC, Vincent-Salomon A, Sigal-Zafrani B, Diéras V, Mathiot C, Mignot L, Thiery JP, Sastre-Garau X, Pierga JY. Prognosis of women with stage IV breast cancer depends on detection of circulating tumor cells rather than disseminated tumor cells. Ann Oncol. (Mar 2008) 19(3):496-500.
- Blumenschein GR, DiStefano A, Caderao J, Fristenberg B, Adams J, Schweichler LH, Drinkard L. Multimodality therapy for locally advanced and limited stage IV breast cancer: the impact of effective non-cross-resistance late-consolidation chemotherapy.Clin Cancer Res. (dec. 1997) 3(12 Pt 2):2633-7.
- Chung, CT., Carlson, RW., Goals and Objectives in the Management of Metastatic Breast Cancer. The Oncologist, (Dec. 2003) Vol. 8, No. 6, 514520.
- Yeatman TJ. The natural history of locally advanced primary breast carcinoma and metastatic disease. Surg Oncol Clin N Am (1995);4:569589.
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