Treatment patterns in patients with advanced breast cancer

Abstract

OBJECTIVE:

The aim of this work was to analyze chemotherapy treatment patterns in patients with advanced breast cancer who had been previously exposed to an anthracycline, a taxane, and capecitabine.

METHODS:

This retrospective cohort study used medical and pharmacy administrative claims with health-plan enrollment data and medical-record review from a large, US-based health insurer database, the HealthCore Integrated Research Database. Women were included if they were aged > or =18 years at the initial breast cancer diagnosis between January 1999 and July 2005 and had received all 3 drug classes of interest, as well as an initial diagnosis of American Joint Committee on Cancer stage I to III breast cancer with metastatic recurrence or an initial diagnosis of stage IV disease. Information about demographics, clinical and pathologic characteristics, survival, and treatments were obtained from computerized data and medical record review. Descriptive analyses were conducted to characterize the treatment patterns.

RESULTS:

One hundred forty-four women with advanced breast cancer were identified. Patients ranged in age from 28 to 76 years, with a mean (SD) age of 48.2 (9.1) years, and with 54 patients (37.5%) aged 40 to 49 years and 48 patients (33.3%) aged 50 to 59 years at the time of initial diagnosis. Ninety-three patients (64.6%) were white, 15 (10.4%) were black, 7 (4.9%) were Hispanic, and 4 (2.8%) were Asian. Overall, 89 patients (61.8%) received > or =1 additional chemotherapy regimen after exposure to all 3 chemotherapy agents of interest; 55 (38.2%) received > or =2 additional regimens. A variety of chemotherapeutic regimens were prescribed; 14 monotherapy regimens and 37 combination therapy regimens were used. The most common regimens (both as single agents and combination therapy) included gemcitabine, vinorelbine, or retreatment with a taxane. Of the 89 patients who received > or =1 retreatment, 7 (7.9%) were retreated with anthracycline, 12 (13.5%) with a taxane, and 9 (10.1%) with capecitabine. For first and second treatment after exposure to all 3 agents of interest, the most common single-agent regimens were gemcitabine (first: 17 patients [19.1%]; second: 9 patients [16.4%]) and vinorelbine (first: 14 patients [15.7%]; second: 9 patients [16.4%]). The most common combination therapies for first retreatment were carboplatin based (6 patients [6.7%]).

CONCLUSIONS:

Of these patients with advanced breast cancer, 61.8% received > or =1 additional chemotherapy regimen after previous treatment with an anthracycline, a taxane, and capecitabine. The variety of agents prescribed suggests a lack of standard of care. Rigorous clinical effectiveness studies of common regimens in heavily pretreated and chemotherapy-resistant populations with breast cancer are warranted.

Breast and Prostate Cancer Data Quality and Patterns of Care (PoC-BP) Study

Started in 2005, the Breast and Prostate Cancer Data Quality and Patterns of Care (PoC-BP) study is the National Program of Cancer Registries' most comprehensive PoC study, involving researchers from CDC and seven states in different geographic areas. The study examines—

• Patterns of initial (first course) treatment received by prostate cancer and female breast cancer patients.
• The extent to which that care is concordant with nationally recognized treatment guidelines.
• How patterns of cancer care vary by patient-, provider-, and health system-level factors.
• The quality of the cancer data for the study.

The routinely collected registry data were supplemented by re-abstracting hospital records and obtaining information about adjuvant treatment and comorbidity from physicians and outpatient facilities. In addition, the study data were linked with secondary files, including Medicare claims, U.S. Census Bureau socioeconomic status data, and hospital/physician characteristics data.

Several manuscripts providing key results have been published in peer-reviewed literature—

CANCER TYPES

Breast Cancer

Breast cancer usually affects women, but men can get it too. 90% of those who are diagnosed with breast cancer lose their lives to the cancer spreading to the rest of their bodies. People will often have a lump in the breast, which is why mammography and self-exams can help detect the cancer early.

NFCR RESEARCH

Detection

• MOST BREAST CANCER HAS A SPECIFIC MARKER THAT COULD BE USED TO IDENTIFY THE CANCER, BUT OUR TECHNOLOGY CAN’T SEE THESE MARKERS.  NFCR IS WORKING TO MAKE CURRENT IMAGING TECHNOLOGY MUCH MORE SENSITIVE SO THAT IT CAN FIND THE MARKERS AND DETECT BREAST CANCER IN ITS EARLIEST STAGE.   

Treatment

• ONE CURRENT THERAPY TO SLOW CANCER GROWTH IS USED FOR A THIRD OF BREAST CANCER PATIENTS, BUT WAS THOUGHT TO BE INEFFECTIVE FOR THE OTHERS.  NFCR IS CONDUCTING CLINICAL TRIALS OF A NEW TREATMENT THAT COMBINES THE EXISTING THERAPY WITH A NEW TECHNIQUE AND CHEMOTHERAPY AND COULD BE USED FOR ALL PATIENTS.  INITIAL RESULTS HAVE SHOWN REDUCED TUMOR SIZE AND COULD LEAD TO A NEW TREATMENT THAT WILL REACH MORE PEOPLE.
• NFCR IS DESIGNING A NEW ANTI-CANCER DRUG THAT WILL TARGET CANCER PROTEINS THAT PREVENT HEALTHY PROTEINS FROM STOPPING CANCER GROWTH.  THIS NEW TECHNOLOGY HAS MAJOR IMPLICATIONS FOR THE POSSIBILITY OF STOPPING THE SPREAD OF CANCER.
• A COMMON CHEMOTHERAPY DRUG (TAXOL) DOES NOT WORK ON EVERYONE. NFCR IS DEVELOPING A TEST THAT WILL SHOW IF THE DRUG WILL WORK OR NOT, BEFORE TREATMENT IS STARTED.  THIS WILL AVOID WASTING TIME ON A TREATMENT THAT WON’T WORK.
• NFCR IS DEVELOPING A WAY TO KILL CERTAIN BREAST CANCER CELLS THAT ARE RESISTANT TO TREATMENT. INSTEAD OF DYING, THESE CELLS SEEM TO DISAPPEAR, BUT BRING THE CANCER BACK YEARS LATER.
• NFCR IS RESEARCHING THE SPREAD OF CANCER, WHICH IS WHAT MAKES CANCERS EVEN MORE DANGEROUS. WE ARE WORKING ON A NEW TREATMENT THAT COPIES THE INTERACTION BETWEEN GENES AND PROTEINS THAT SLOW THE SPREAD OF CANCER AND COULD PREVENT IT FROM SPREADING ALL TOGETHER.
• ANOTHER WAY NFCR IS TRYING TO STOP THE SPREAD OF CANCER IS BY IDENTIFYING THE GENES THAT ALLOW CANCER CELLS TO MOVE THROUGHOUT THE BODY. ONCE THESE GENES ARE IDENTIFIED, WE WILL CREATE A TECHNIQUE TO STOP THE GROWTH OF CANCER IN HEALTHY AREAS AND TO PREVENT THE CANCER CELLS FROM MOVING TO BEGIN WITH.
• NFCR MANAGES THE TISSUE BANK CONSORTIUM IN ASIA, A TISSUE SAMPLE PREPARATION AND STORAGE FACILITY THAT SERVES AS AN EXTENSIVE DATA HUB TO SUPPORT RESEARCH. SO FAR, THE TISSUE BANK HAS IMPROVED THE CLASSIFICATION OF BREAST CANCER, CREATED TESTS TO DIAGNOSE CANCER, AND LED TO BETTER THERAPIES.