Rethinking the MBC Paradigm

New trends in treating metastatic breast cancer
Kathryn E. Vinson, MS, CCRC

When it comes to metastatic breast cancer (MBC), a whole host of questions arise. What does this mean for me and my family? Do we treat this aggressively, or look for comfort care? There are no easy or simple answers to any of these questions. Treatment also depends on a lot of factors such as the extent of the metastases, hormone receptor status, BRCA mutation status, age of the patient, and wishes of the patient and her family. This disease is still thought to be incurable; however, new treatment innovations are helping to lengthen the lives of these brave warriors. Let’s takes some time to talk today about how these innovations are changing the way doctors and patients look at this dreaded disease.

Why isn’t surgery used more often in the treatment of MBC?  Well, once breast cancer spreads to the lymph nodes and other parts of the body, it is considered a systemic disease; therefore, doctors tend to focus on treating the disease as a whole, rather than removing the primary tumor.  Indeed, Dr. Anees B. Chagpar (2018) of the Yale Comprehensive Cancer Center tells us that rates of removal of the primary tumor have fallen over the last decade, but two recent studies may change that trend.  Dr. Chagpar describes these, one with systemic therapy prior to surgery, and the second with surgery prior to systemic therapy. In the first study, no significant difference was seen in survival rates at two years; the second trial showed similar results at three years, but at five years follow-up, significant differences were seen in overall survival. While there are several factors that can account for the differences seen here, such as the order of the treatment and length of follow-up, it is well worth additional study.

Any decision on removal of the primary tumor must be weighed against the risks of surgery.  One reason for the low rate of surgery in this population is the higher 30-day morbidity risk in patients with metastatic disease versus those without metastatic disease.

Reinert and Barrios (2015) tell us that 60-80% of breast cancer in Western nations is hormone receptor positive, and that proportion may be increasing.  In this type of breast cancer, the tumor responds to the hormones circulating in our bodies; as such, most doctors begin with hormone blockers.  Tamoxifen has been used for years, but researchers are seeing great results with other types of hormone blockers such as anastrozole, letrozole, and exemestane.  These drugs represent the “typical” first line of treatment in hormone receptor positive disease. Researchers are currently looking at how these other drugs, when used in various combinations and orders, can extend patient lives and improve quality of life.

A few weeks ago, in Immunotherapy and Cancer, we discussed how these promising new treatments work.  On June 4^th of this year, the National Cancer Institute reported the success of an immunotherapy agent in a patient with MBC.  This patient had failed standard hormone and chemotherapy treatments.  Utilizing the DNA and RNA sequences from her own tumors, researchers identified 62 different mutations within those tumor cells that could be utilized by the treatment.  With the aid of Tumor Infiltrating Lymphocytes (TILs) that recognized four of the mutations, and pembrolizumab to help prevent the inactivation of T-cells, the patient is now cancer free for 22 months!

If you or a loved one are one of the brave warriors battling this disease, there are several things you can do.  Arm yourself with knowledge – stay on top of the latest trends in battling these diseases; take a look at our page for clinical trials and discuss these options with your doctor.  Also, know that you are not alone, whether you are a caregiver or patient, there are tremendous resources available to you to help you through this fight. We have pages dedicated to financial help, support groups, and cancer associations that can lend tremendous support to you and your loved ones.

From all of us here at Cancer Horizons, we send our love and prayers to all of those battling this dreaded affliction.

Sources:
https://www.onclive.com/printer?url=/publications/oncology-live/2018/vol-19-no-6/taking-a-new-look-at-primary-resection-in-distant-metastatic-breast-cancer
http://journals.sagepub.com/doi/abs/10.1177/1758834015608993
https://www.cancer.org/cancer/breast-cancer/treatment/treatment-of-breast-cancer-by-stage/treatment-of-stage-iv-advanced-breast-cancer.html
https://www.cancer.gov/news-events/press-releases/2018/immunotherapy-targets-breast-cancer-case-report