Adjuvant Endocrine Therapy in Early Stage Breast Cancer: Adherence and Clinical Outcome

NCT03761420 | Completed

• 1 other identifier: 2017/1356
• Study Type: observational
• Target: 1,411
• Locations: 1 country
• Sites: 1

Brief Summary

Breast cancer is the most common cancer among women in Norway. In 2016, 3402 new cases were diagnosed (3371 in women). Breast cancer is still the second most common cause of death from cancer among women with 585 breast cancer deaths in Norway in 2015. The majority of the patients (70-75 %) belong to the Luminal subtypes, which comprise the hormone receptor (oestrogen receptor (ER) and/or progesterone receptor (PR)) positive tumours. The most important systemic adjuvant therapy in luminal breast cancers is a long-lasting administration of per-oral anti-oestrogen medication. A systemic hypo estrogenic state in the body may be created by the selective oestrogen receptor modulator tamoxifen or by inhibitors of the peripheral systemic aromatization of adrenal androgens into estrogens (aromatase inhibitors). Initially, tamoxifen was given adjuvant for 2 years, later prolonged to 5 years and recently an extension to 10 years has been recommended for premenopausal women. Aromatase inhibitors were introduced in Norwegian treatment guidelines in 2002. Currently, they are recommended in postmenopausal patients for 5 years, either as monotherapy or in concert with tamoxifen (aromatase inhibitors for 2 years followed by tamoxifen for 3 years). In premenopausal breast cancer patients, tamoxifen still is the drug of choice. Two of the major underlying reasons for late recurrences in luminal breast cancer subtypes are development of endocrine resistance to tamoxifen and aromatase inhibitors or failure of taking the medication as prescribed. Higher mortality has been shown for breast cancer patients with reduced tamoxifen adherence. The patients' ability to follow instructions and recommendations are probably overestimated in controlled trials due to patient selection and close follow-up in the study setting. Some patients experience distressing side effects like hot flushes, fatigue, joint pain, mood swings and vaginal dryness. To the investigators' knowledge, there are few studies in Norway regarding discontinuation of endocrine treatment in breast cancer. In this study they will investigate the long-term discontinuation pattern to oral adjuvant systemic endocrine therapy in a large cohort of breast cancer patients treated in St. Olav's hospital in Trondheim, Norway, and the association between adherence to endocrine treatment and long-term survival.

Conditions

Breast Neoplasm

Keywords

Medication Adherence; Antineoplastic Agents, Hormonal; Chemotherapy, Adjuvant; Treatment Outcome

Outcome Measures

Primary Outcomes (2)

• Medication Possession Ratio (MPR) as a proxy for medication adherence

  see Detailed description

  0-5 years after surgery for breast cancer

• Survival

  Breast cancer specific survival according to adherence and non-adherence

  5-14 years after surgery for breast cancer

Study Arms (1)

breast cancer postoperative

got surgery for breast cancer in St Olavs Hospital, Trondheim, during 2004-2013

Eligibility Criteria

• Age: 20 Years - 100 Years
• Sex: female
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

breast cancer patients treated (surgery) at St Olavs Hospital in Trondheim, Norway, during 2004-2013.

You may qualify if:

• Luminal breast cancer

You may not qualify if:

• Non-Luminal breast cancer

Sponsors & Collaborators

• St. Olavs Hospital: lead
• Norwegian University of Science and Technology: collaborator

Study Sites (1)

St Olavs Hospital

Trondheim, Norway

Location

MeSH Terms

Conditions

Breast Neoplasms; Medication Adherence

Condition Hierarchy (Ancestors)

Neoplasms by Site; Neoplasms; Breast Diseases; Skin Diseases; Skin and Connective Tissue Diseases; Patient Compliance; Patient Acceptance of Health Care; Treatment Adherence and Compliance; Health Behavior; Behavior

Study Officials

• Anne Irene Hagen, md phd

  St. Olavs Hospital

  STUDY DIRECTOR

Study Design

• Study Type: observational
• Observational Model: CASE ONLY
• Time Perspective: RETROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: November 28, 2018
• First Posted: December 3, 2018
• Study Start: August 1, 2019
• Primary Completion: April 1, 2021
• Study Completion: April 1, 2021
• Last Updated: May 3, 2021

Record last verified: 2021-04

Locations

NO (1)