BREAST CANCER THEN AND NOW

Dr. Mahendra Perera,

(MBBS, MD, Dip.RT)

Consultant in Clinical Oncology & Radiotherapy Honorary Fellow of Sri Lankan College of Oncologists Principal Investigator – International Multi-Center Clinical Trials.

Forty years ago cancer was considered not only taboo, but was thought to have immediately association with death. Hardly anyone talked about cancer then. Once a patient was diagnosed, their relatives begged others not to talk about it. Of course, the doctors had to tell the patient the truth but we understood their loved ones were trying to shield them from what was thought to be a death sentence.

It was a dreadful sequence of events. However, we are now in an era where the Breast Cancer has been largely spoken about in various platforms. Majority of the speakers focus mostly on its new treatment modalities along with the new term ‘Precision Medicine’ which has made a major breakthrough in breast cancer cure today.

More women are diagnosed with breast cancer than any other type of cancer. It is now estimated to be more than 25% of all female cancers. It has been widely studied throughout the world. In fact, major research on breast cancer has paved the path for breakthroughs in other types of cancer research as well. In other words, breast cancer treatment has be come a core model for other cancer treatments.

Though young breast cancer survivors who remained cancer-free, lived with excellent quality of life, they had to go through variety of psychological concerns. The term ‘five-year survival’ tells you what percentage of people diagnosed having breast cancer would live at least five years after their cancer is found. On the average the five-year survival rate for women with non-metastatic (not spread) invasive breast cancer is around 85 %. The average 10-year survival rate for women with invasive breast cancer is 75%.

If the cancer has spread to the regional lymph nodes, the five-year survival rate drops to 65%. If the cancer has further spread to a distant part of the body, the five-year survival rate drops down below 35%.

At the time of first diagnosis with breast cancer, about five percent will have cancer already spread outside of the breast and to nearby lymph nodes. This is called “de novo” metastatic breast cancer. Even if the cancer is found at a more advanced stage, new treatments still can help many people with breast cancer maintain a good quality of life for a reasonable time.

Some cancer patients were knowingly or unknowingly over-treated or under-treated for the disease. This was specially seen when there were uncertainties raised by medical specialists on debatable clinical situations. What extent to treat precisely is well understood now by the newer investigations and drugs that have been developed. These drugs are targeting the defective genes or defective pathways of cancer spreading.

This must be addressed very accurately and early during their treatment to avoid over-diagnosis and over-treatment. There are hardly any such situations observed now because of the availability of molecular diagnostic facilities and ‘precision medicine’.

In general most types of cancer treatments have improved over the time and cancer is now targeted with far greater precision than in the past. Current refined techniques in surgery, radiotherapy and chemotherapy mean that people live with fewer side effects than they used to experience in the 1970s and 80s. However, we are now seeing a newer spectrum of side effects emerging from newer treatments.

Essentially all untreated breast cancer patients will die of the disease. Their co-existing medical conditions will also increase with age. So older patients with breast cancer have a higher probability of dying of causes other than breast cancer.

On the basis of these observations, the concept of ‘Personal Cure’ emerged. A significant number patients with breast cancer achieving a ‘Personal Cure’ after curative treatment will eventually die of a different cause such as cardiovascular disease, lung disease or stroke.

The term ‘Statistical Cure’ has been defined on the basis of population survival figures. Thus, it is considered that a group of patients with breast cancer achieves cure in statistical terms if their probability of survival becomes comparable to the probability of survival in the general population.

Breast Cancer diagnosed by mammogram early (Stage I) has excellent survival figures exceeding 90% at 20 years following any form of surgical resection alone even 25 years after diagnosis. The survival of patients with stages II, III and IV breast cancer have a higher chance of relapse leading to lesser chances of survival. It is generally believed once the breast cancer spreads to other organs, the chances of cure becomes remote with most available treatment modalities.

Once the cancer is spread, surgical resection is a futile exercise and does not alter the natural progression of the disease. Breast cancer treatment is becoming more individualized as doctors learn more about the disease. It’s now seen as a disease with many subtypes. These sub types do not play a role in staging the breast cancer but becomes greatly important in treatment decisions.

The ability to isolate specific genes and classify breast cancer according to a patient’s genomic alterations, is the beginning of more tailored treatment options. There are many special tests that can tell your doctor more about breast cancer so that they can then decide on the best course of treatment for that person and use information of patient’s genes to predict how their cancer will respond to different treatments.

This is where Precision Medicine holds the promise of truly personalized treatment which provides every individual breast cancer patient with the most appropriate diagnosis and targeted treatment. Precision medicine for breast cancer involves analyzing the genetic makeup of your cells or, if you have cancer, the makeup of your cancer cells.

Once a patient is diagnosed with breast cancer, she would need a proper biopsy sample which should be analyzed on basic testing as well as at an advanced genomic testing because your genes may influence the way your body acts against cancer drugs. Such drug – gene interactions is called pharmacogenomics. It helps your doctor to see whether that particular drug could precisely work for you. At the same time, if your cancer progresses despite treatment, your doctor might recommend testing the genetic makeup of your cancer cells. This test, called ‘tumor cell sequencing’ is used to see changes or alterations in the cancer to decide on the best drug for you.

Some cancers run in families. Inherited gene mutations will increase your risk of breast cancer. We sometimes recommend a test called ‘BRACA’ gene testing for people with a strong family history of breast cancer. Women who have these genes have an increased risk of developing the disease. This same ‘BRACA’ test is used to determine whether you would respond to a specific drug when your cancer is disseminated.

Many newer genetic tests are available now, depending on a person’s family history of cancer. However, one should not have a fear that, presence of such genes would necessarily cause you breast cancer.

Early detection is not always the cure for breast cancer. But once detected early it could be successfully treated. Surgery remains the most definitive treatment for breast cancer. It could end up in total removal or partial removal of your breast whenever it is operable. Surgery cannot cure the breast cancer. Cancer needs a multi-modal treatment. Surgery would make matters worse if it is performed in an advanced stage breast cancers.

Such advanced breast cancers should be treated with chemotherapy to downsize the tumor before removing surgically. In certain situations there is no need to remove the primary breast cancer at all. Your doctor will tell you if it is so. Breast cancer is not confined to its local area. It is a disease within your whole body.

After surgery, majority of breast cancer patients will require chemotherapy, radiotherapy or hormone therapy as a single modality or in combinations. It is this added treatment which is called the ‘adjuvant therapy’ that remains the mainstay of breast cancer cure.