XRAYS - Making Sense of Cancer Headlines

FORCE’s eXamining the Relevance of Articles for Young Survivors (XRAYS) program is a reliable resource for breast cancer research-related news and information. XRAYS reviews new breast cancer research, provides plain-language summaries, and rates how the media covered the topic. XRAYS is funded by the CDC.

XRAYS logo and women

Immunotherapy may lead to long-term remission of metastatic breast cancer

This research is relevant for:

Checked Breast cancer survivors

Unhecked Women under 45

Unhecked Women over 45

Unhecked Men with breast cancer

Checked Metastatic breast cancer

Unhecked Triple negative breast cancer

Unhecked Previvors

Unhecked BRCA mutation carriers

Checked ER/PR +

Unhecked Her2+ breast cancer

Checked Special populations: Metastatic breast cancer patients with ER+, HER- breast cancer

Be a part of XRAYS

XRAYS:  Making Sense of Cancer Headlines

Metastatic breast cancer is often difficult to treat. In a new approach, called adoptive cell therapy (ACT), a patient’s own T-cells (a type of cancer-fighting immune cells) are collected, multiplied in a lab, and then returned to the patient. The goal is to enhance the patient’s immune system with many more T-cells that recognize and attack metastasized tumor cells. This study reports on a single patient whose metastatic breast cancer is still in remission (no evidence of disease) after more than 22 months following ACT. (8/16/18)



This study is about:

Adoptive cell therapy (ACT), a new treatment for metastatic breast cancer that resulted in complete tumor regression in 1 patient.

Why is this study important?

Metastatic breast cancer is breast cancer that has spread to other places in the body. It may be an initial diagnosis (at stage 4) or develop as a recurrence after a stage 1, 2 or 3 breast cancer metastasizes.

Metastatic breast cancer can be difficult to treat when cancer cells are located in many parts of the body and can resist standard treatment. Immunotherapies like the one in this study boost the patient’s own defense system to better fight cancer.

This study is important because it is an example of a new, personalized treatment approach that resulted in complete regression of one woman's metastatic breast cancer—an unusual occurrence.

Study findings: 

This research is a case study of one woman with metastatic breast cancer and an exceptionally effective treatment.

Before treatment, the 49-year old patient had advanced estrogen receptor-positive, HER2-negatve metastatic breast cancer in multiple locations, with tumors in her breast, chest wall and lymph nodes. Several standard treatments, including different chemotherapies, were unsuccessful.

In an ongoing clinical trial, the woman was treated by experimental adoptive cell therapy (ACT).  Researchers first selected some of her immune cells—specifically ones that could recognize and attack her tumor cells. These tumor-infiltrating lymphocytes (TILs) were then grown to much larger numbers in the lab; and then these cancer-fighting TIL cells were reinjected into the patient.

The result was surprisingly effective. At 22 months after treatment, none of the tumors that were present before treatment were detected.

What does this mean for me?

If you have metastatic breast cancer, you will likely be treated using a standard method of care. This study is investigational, meaning that the safety and effectiveness of the procedure has yet to be determined. While this woman responded well and is now living with no detectable cancer, researchers do not know whether her response will be typical, if it will vary between patients, if it was a fluke, or if unintended side effects might occur. It may be some time before we understand whether this treatment is truly useful.

This woman was part of an ongoing clinical trial to test this technique. This trial is enrolling participants who have "metastatic digestive tract, urothelial, breast, or ovarian/endometrial cancer who have a tumor that can be safely removed....All patients must be refractory to approved standard systemic therapy." If this fits your situation, you may want to consider participating in this trial or in a related study. More information on eligibility for this trial can be found here, or for other trials for metastatic breast cancer at the following link. You can search for open trials with our clinical trial research tool or via ClinicalTrials.gov.

Questions to ask your health care provider:

What is the best treatment approach for my metastatic breast cancer?

Am I eligible for any clinical trials?

What are the risks and potential benefits of participating in a clinical trial?

What is the success rate with my treatment for metastatic breast cancer?

Share your thoughts on this XRAYS article by taking our brief survey.


Study background:

Metastatic breast cancer is defined as breast cancer that has spread and formed tumors at distant places in the body. It may be a woman’s initial diagnosis (at stage 4) or develop as a recurrence after a stage 1, 2 or 3 breast cancer metastasizes.

Data from a 2017 SEER study (Mariotto, et al.) indicated that over 170,000 women in the U.S. are living with metastatic breast cancer (and there are also several hundred men with metastatic breast cancer). Five-year survival rates for metastatic breast cancer patients have increased. For ages 18-49, that rate rose from 18% between 1992-1994 to 36% between 2005-2012. During the same time, average survival for women ages 15-49 whose first diagnosis was metastatic breast cancer increased from 22.3 months to 38.7 months. Average survival time for women ages 50-64 whose first diagnosis was metastatic breast cancer increased from 19.1 months to 29.7 months.  

Despite longer life spans after diagnosis, many deaths due to metastatic breast cancer still occur annually. Based on Mariotto’s study, only about 17% of women with living with metastatic breast cancer have survived more than 10 years. Metastatic breast cancer can be difficult to treat because cancer cells spread to many parts of the body and often resist standard treatment. Finding new approaches or treatments to slow, halt or reverse cancer growth continues to be an active area of research.

One promising technique for treating metastatic cancer is adoptive cell therapy (ACT), also known as adoptive transfer. Researchers extract a patient’s own tumor-infiltrating lymphocytes (TILs); these are unique immune cells that can recognize and attack her tumor cells. These TILs are then grown to vastly larger numbers in the lab and then they are reintroduced into the patient. 

Adoptive cell transfer has been used successfully with melanoma and colorectal cancer. Approximately 50% of patients with metastatic melanoma who were treated with ACT have shown complete remission. Some types of ACT involve genetically modifying immune cells to boost their effectiveness against cancer cells. In this study, however, the patient’s cells were selected and allowed to multiple in the lab, but they were not genetically modified.

This study is very important because it is the first successful application of T-cell immunotherapy for late-stage breast cancer. It holds hope of a new treatment approach that resulted in complete remission of one woman's metastatic breast cancer. Such a complete positive result is highly unusual.

Researchers of this study wanted to know: If treatment with a patient's own immune cells would lead to tumor remission.

Population(s) looked at in the study:

This research is a case study of a 49-year-old woman with advanced metastatic breast cancer and an exceptionally effective treatment. Originally diagnosed at age 39 with DCIS in her left breast, she then had a modified radical mastectomy. She was in remission for 10 years before being diagnosed again with ER+, HER2- metastatic breast cancer with tumors in multiple locations, including several lymph nodes, her right breast and left chest wall. She then had several types of chemotherapy and endocrine therapies to treat her metastatic cancer that did not halt growth of her tumors.

Study findings:  

This study approach is based on immunotherapy—stimulating the body's own defense system to attack tumor cells. This happens naturally to some extent, but as cancer grows, a person’s immune system becomes overwhelmed and is less able to respond.

In this study, researchers collected two types of cells from the patient: tumor cells from a metastasis in the right breast and immune cells from the patient's blood. First, they identified unique proteins on the surface of the tumor cells. (These are different from the proteins of normal cells.) Because not all immune cells are alike, they then looked at the patient’s immune cells to identify the ones that could specifically target the tumor proteins. These selected tumor infiltrating lymphocytes, or TILs, were grown in large numbers in the lab and injected back into the patient, greatly strengthening her own body’s defense against her cancer.

The result was surprisingly effective: 6 weeks after treatment her tumors were reduced in size by 51%, and by 22 months after treatment, the masses in the woman's chest wall, right breast and lymph nodes were undetectable.


The largest limitation of this study is number of participants—it is a case study of just one patient. Melanoma treated by ACT is effective for 50% of patients treated; however, it is unclear what proportion of metastatic breast cancer patients would respond to this therapy. While this woman responded well and is living without detectable cancer, researchers cannot be sure if her response will be typical, whether it will vary, or if it is a fluke. This is part of an ongoing clinical trial and data from additional participants may be available in the near future.

Whether or not ACT is safe and effective is still unknown. Patients with other metastatic cancers who have been treated with ACT have experienced side effects. This patient experienced low blood phosphate levels, a high fever (associated with immune cell depletion), and other treatable major side effects during ACT. But the ACT did not appear to adversely affect her normal tissue. It is too early to know if other unintended side effects would occur when more patients are treated using this technique.

Another limitation of this study is that as part of the procedure, the patient was also treated briefly with the immunotherapy agent pembrolizumab once before ACT and three times after ACT. Pembrolizumab is considered a checkpoint block that can halt cancer cell growth to allow the immune system to attack the cancer more effectively. It is possible that the positive effects observed are due to this drug rather than the ACT treatment. However, historically, pembrolizumab does not have a significant effect on ER+ tumors like those in this patient. Furthermore, when researchers examined the tumor cells of this particular patient, the protein recognized by pembrolizumab was not present. Therefore, it seems unlikely that this drug accounts for the remission observed (although it may aid ACT effectiveness). Further ACT testing without this drug is needed to clarify this issue.

The patient treated is a younger woman (age 49) who does not have a hereditary mutation in a breast cancer predisposition gene. Whether or not her result will apply to women with hereditary mutations is unclear.


This is an exciting and promising new technique. Much more data is needed to determine its safety and effectiveness and its potential limitations or side effects.

Share your thoughts on this XRAYS article by taking our brief survey.

Posted 8/16/18


Zacharakis N, Chinnasamy H, Black M, et al. "Immune recognition of somatic mutations leading to complete durable regression in metastatic breast cancer." Nature Medicine. 2018;24:724-730.

Associated clinical trial: NCT 01174121 Immunotherapy Using Tumor Infiltrating Lymphocytes for Patients With Metastatic Cancer

Mariotto AB, Etzioni R, Hurlbert M, et al. "Estimation of the Number of Women Living with Metastatic Breast Cancer in the United States." Cancer, Epidemiology, Biomarkers and Prevention. 2017;26(6):809-815. DOI:10.1158/1055-9965.EPI-16-0889

National Cancer Institute: "Study estimates number of U.S. women living with metastatic breast cancer." Posted May 18, 2017.

Back to XRAYS Home

Find older XRAYS studies and articles

By keyword search:

By date range:

FORCE:Facing Our Risk of Cancer Empowered