Abstract P4-11-11: Patient preferences for minimally invasive and conventional locoregional treatment for early-stage breast cancer; A utility assessment

Introduction

Breast cancer (BC) is increasingly diagnosed in an early stage due to improved imaging techniques and mammography screening. Non- or minimally invasive treatments, such as radiofrequency ablation (RFA) and MR-guided high-intensity focused ultrasound (MR-HIFU) ablation are currently being developed as alternatives to breast surgery. Patients' preferences with regard to these new treatments have not been investigated. The aim of this study is to assess the preferences of BC patients and healthy women regarding these new techniques, compared to conventional locoregional treatments.

Materials and methods

Six health states containing descriptions of BC treatments with their clinical consequences were developed based on literature and clinical expertise. Six treatment scenarios for treatment of early-stage BC without indication for adjuvant systemic therapy were proposed: 1) mastectomy with sentinel lymph node biopsy (SLNB); 2) mastectomy followed by direct reconstruction and SLNB; 3) breast conserving surgery with SLNB and whole breast radiotherapy; 4) radiofrequency ablation preceded by SLNB and followed by whole breast radiotherapy; 5) MR-HIFU ablation preceded by SLNB followed by whole breast radiotherapy; and 6) ablative partial breast radiotherapy (single dose) preceded by SLNB. Patients and healthy volunteers rated each scenario and corresponding health state by both visual analogue scale (VAS) and time trade-off (TTO). Eligible subjects are female BC patients who completed treatment > 12 months ago and women aged > 40 years without BC history. Patients were recruited from the UMBRELLA cohort at the department of Radiation Oncology of the University Medical Center Utrecht (The Netherlands). Healthy volunteers were friends or relatives of the BC patients enrolled in the study. Mean and standard deviation of VAS and TTO derived utility scores were calculated and health states were ranked by preference. Repeated measures ANOVA was used to test whether difference between ratings was significant. Spearman correlation coefficient was used to compare VAS and TTO scores.

Results

In a preliminary analysis in 23 women (18 patients and 5 healthy volunteers) mean age was 59±10.6 years. Responders rated breast conserving surgery as most preferred treatment (VAS 0.88±0.1, TTO 0.91±0.08). VAS scores were strongly correlated to TTO scores (ρ=0.74, p-value < 0.005). Updated and more detailed results on 150 patients and healthy women will be presented in December.

Conclusion

We are performing a utility analysis of new and existing breast cancer treatments in breast cancer patients and healthy volunteers. This study will yield important information to guide the development and innovation of breast cancer therapies in the future.

Citation Format: Knuttel FM, van den Bosch MMAAJ, Young Afat DA, Emaus MJ, van den Bongard DHJG, Witkamp AJ, Verkooijen HM. Patient preferences for minimally invasive and conventional locoregional treatment for early-stage breast cancer; A utility assessment. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P4-11-11.

Abstract P5-08-46: Competing causes of death among women with breast cancer in South East Asia: Effects of ethnicity, and age at diagnosis and stage at diagnosis

Background: Over the past decades, breast cancer survival has improved substantially and many patients die of other, non-breast cancer related causes. In South East Asia, where large ethnic differences exist in stage at presentation and overall survival, causes of death of breast cancer patients have been understudied.

Aim: To examine cause-specific mortality among breast cancer patients in multi-ethnic Singapore and investigate effects of ethnicity, and age and tumor stage at diagnosis.

Methods: Data of women diagnosed with breast cancer between 1990 and 2011 at the National University Hospital in Singapore were retrieved from the hospital-based breast cancer registry. Cause of death was categorized as breast cancer (ICD8 174; ICD9 174; ICD10 C50), cardio- and cerebrovascular disease (ICD8 390 to 459; ICD9 390 to 459; ICD10 I00 to I99), other malignancies (ICD8 140 to 239; ICD9 140 to 239; ICD10 C00 to D48 except codes for death resulting from breast cancer), and death from other causes (all ICD codes except those already listed). Patients with unknown cause of death (n=6) were classified as death from other cause. Chi square statistics were used to compare cause of death distributions.

Results: Of 4108 patients, median age at diagnosis was 51 years (range 21- 98 years). The majority of women were Chinese (n=3223, 78%), followed by Malay (n=517, 12%), Indian (n=257, 6%) and other ethnicities (n=111, 3%). After a median follow-up of 7 years, 1125 (27%) patients died: 910 (81%) patients died of breast cancer, 70 (6%) of cardio- and cerebrovascular disease, 71 (6%) of other malignancies, and 83 (7%) of other causes. Compared with other ethnicities, Malay women most frequently died as a result of breast cancer (n=178, 90%). The highest percentage CVD deaths was observed among Indians (n=7, 11%). Breast cancer accounted for 92% of deaths in women younger than 50 years at diagnosis and for 60% in women older than 65. The proportion of deaths as a result of CVD, other cancer or other causes increased with age. Patients with higher tumor stages at diagnosis were more likely to die of breast cancer (96% of deaths of patients with TNM4 were breast cancer related).

Conclusion: The present study showed that breast cancer is the most important cause of death in breast cancer patients among all ethnic groups, and ages and stages in South East Asia. The highest risk of death due to breast cancer in Malay women might be explained by their presentation at advanced stages and young age at diagnosis. Breast cancer is less likely to be the cause of death in women of Chinese ethnicity, older age at diagnosis and early tumor stage. In these groups more attention for competing causes of death, in particular CVD, should be a priority for the future.

Citation Format: Ho P, Rijnberg N, Gernaat SAM, Emaus MJ, Grobbee RDE, Lee SC, Hartman M, Verkooijen HM. Competing causes of death among women with breast cancer in South East Asia: Effects of ethnicity, and age at diagnosis and stage at diagnosis. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P5-08-46.