Rural-Urban Variation in Time to Diagnosis and Treatment of Colorectal or Breast Cancer in Victoria, Australia

Background: Rural-urban disparities in cancer outcomes are found in many countries, though these vary by cancer type. In Victoria, Australia, survival is poorer for rural patients with colorectal cancer, but not breast cancer. Delayed diagnosis and treatment may contribute to disparities, but previous studies have not compared the timeliness of rural and urban pathways to treatment of these common cancers. Aim: We investigated whether time to diagnosis and treatment differed for rural and urban patients with colorectal or breast cancer in Victoria, Australia. Methods: Population-based, cross-sectional surveys examining events and dates on the pathway to treatment completed by patients aged ≥ 40 and approached within six months of diagnosis, their general practitioner (GP) and specialist. Data were collected from 2013 to 2014 as part of the International Cancer Benchmarking Partnership, Module 4. Six intervals were explored: patient (symptom to presentation), primary care (presentation to referral), diagnostic (presentation/screening to diagnosis), treatment (diagnosis to treatment), health system (presentation to treatment) and total intervals (symptom/screening to treatment). Rural-urban differences were examined for each cancer using quantile regression (50th, 75th and 90th percentiles) models including age, gender, health insurance and socioeconomic status. Results: 433 colorectal (48% rural) and 489 breast (42% rural) patients, 621 GPs and 370 specialists completed surveys. Compared with urban patients, symptomatic colorectal cancer patients from rural areas had a significantly longer total interval at all percentiles: 50th (18 days longer, 95% confidence interval (CI): 9-27), 75th (53, 95% CI: 47-59) 90th (44, 95% CI: 40-48). These patients also had longer health system intervals, ranging 7-85 days longer. This appeared mostly due to longer diagnostic intervals (range: 6-54 days longer). Results were similar when including screen-detected cases. In contrast, breast cancer intervals were similar for rural and urban patients, except the patient interval, which was shorter for rural patients. Conclusion: Consistent with variation in survival, we found longer total and diagnostic intervals for rural compared with urban patients with colorectal cancer, but not breast cancer. The lack of rural-urban differences observed for breast cancer suggest that inequities in the timeliness of colorectal cancer pathways can be ameliorated, and may improve clinical outcomes. Indeed, based on previous research, delays observed in this study could result in stage progression and hence reduced survival. From our results, interventions targeting the time from presentation to colorectal cancer diagnosis in rural populations should be pursued. Countries seeking to understand cancer disparities in their local context may also consider using a pathways approach to identify possible targets for policy intervention.

A three-dimensional steerable optical tweezer system for ultracold atoms

We present a three-dimensional steerable optical tweezer system based on two pairs of acousto-optic deflectors. Radio frequency signals used to steer the optical tweezers are generated by direct digital synthesis, and multiple time averaged cross beam dipole traps can be produced through rapid frequency toggling. We produce arrays of ultracold atomic clouds in both horizontal and vertical planes and use this to demonstrate the three-dimensional nature of this optical tweezer system.

Keeping physically active with rheumatoid arthritis: semi-structured interviews to explore patient perspectives, experiences and strategies

BACKGROUND

Regular physical activity is safe and beneficial for people with rheumatoid arthritis (RA) but the majority of people with RA are less active than the general population and have a higher risk of co-morbidities. Exploring strategies used by physically active people with RA could inform effective methods to support those who are less active.

OBJECTIVE

To explore the perspectives, experiences and strategies employed by people with RA who successfully engage with regular physical activity.

DESIGN

Individual semi-structured interviews and thematic analysis.

PARTICIPANTS

A purposive sample of physically active people with RA.

RESULTS

Twelve females and three males participated (mean age 56, range 29 to 80; mean disease duration 13 years, range 10 months to 46 years). Analysis revealed eight constructs clustered into three themes. Theme 1: 'the individual' incorporated constructs of symptoms, feelings and role; theme 2: 'management' incorporated medical and self-management; theme 3: 'physical activity' incorporated constructs of type of physical activity, including barriers or facilitators. Participants reported a long history of physical activity prior to diagnosis and good support networks. All participants recognised that physical activity was key to their RA management, acknowledged the benefits from engaging in physical activity and were able to overcome barriers. Participants had strong beliefs that physical function would decline without regular physical activity.

CONCLUSIONS

People with RA who successfully maintain physical activity are motivated by a desire to manage symptoms, resist functional decline and maintain health and independence. These findings should be explored with a wider range of people with RA.

In situ fabricated 3D micro-lenses for photonic integrated circuits

Aspheric astigmatic polymer micro-lenses were fabricated directly onto photonic integrated circuits using two-photon lithography. We observed a 12.6 dB improvement in the free space coupling efficiency between integrated ridge laser pairs with micro-lenses to those without.

Abstract P1-07-36: Outcomes and failure of primary endocrine therapy for operable breast cancer in the elderly: A regional North-east of England study

Introduction

Primary Endocrine therapy (PET) to treat oestrogen receptor (ER) positive operable breast cancer in the elderly is used widely in the UK. A previous Cochrane analysis revealed its inferiority in long-term local control in comparison to surgery. As such, current guidance from the Society of International Geriatric Oncologists (SIOG) suggest that PET should be reserved for patients with a reduced life-expectancy (2-3 years) or for those considered unfit for surgery. Inaccurate assessment of life expectancy could lead to treatment failure which is potentially catastrophic for the patient.

The aim of this study was to evaluate treatment failures in elderly breast cancer patients treated with PET and to determine predictors of failure.

Methods

A retrospective observational study was performed on consecutive patients with ER positive early stage breast cancer treated with PET between 2005 and 2015 in the three breast units in the north east of England. The primary outcome measure was treatment failure and the secondary outcome measure was disease progression.

Results

488 patients were included with mean follow up 31 months (SD 23). 465 (95.2%) patients were started on Letrozole as their initial therapy. Overall, 206 patients were still alive with their disease controlled at the end of follow up, 219 had died with their disease controlled and 63 (12%) experienced treatment failure. Kaplan-Meier survival analysis predicted at 3 years 40% of patients to have died with controlled disease and 10% to have failed, leaving 50% living beyond this point with controlled disease. Regression analysis identified younger age [SHR 0.96 (95% CI 0.94 to 0.99) p 0.013], larger tumours [SHR 1.03 (1.01 to 1.06) p 0.015], grade 3 cancers [SHR 3.58 (1.93 to 6.63) p<0.001] and axillary lymph node metastases [SHR 1.93 (1.06 to 3.52) p 0.030] were all independent predictors of treatment failure. Disease progression was reported in 86 (17.6%) of patients.

Conclusions

This is the largest retrospective series conducted evaluating PET treatment failure. Our comparably low rate of failure in comparison to that in the literature (12-85%) reflects good clinical acumen. Clear predictors of failure have been identified, which support previous analyses, further validating our results. Patients are able to live longer term (beyond 3 years) and maintain local disease control, which may represent a viable long-term treatment in the absence of risk factors for failure. Further work on our series is underway examining the effect of decision-making on PET outcomes.

Citation Format: Thomas R, Rowell R, Crichton S, Cain H. Outcomes and failure of primary endocrine therapy for operable breast cancer in the elderly: A regional North-east of England study [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P1-07-36.

Learning the Preferences of Physicians for the Organization of Result Lists of Medical Evidence Articles

Background: Online medical knowledge repositories such as MEDLINE and The Cochrane Library are increasingly used by physicians to retrieve articles to aid with clinical decision making. The prevailing approach for organizing retrieved articles is in the form of a rank-ordered list, with the assumption that the higher an article is presented on a list, the more relevant it is.

Objectives: Despite this common list-based organization, it is seldom studied how physicians perceive the association between the relevance of articles and the order in which articles are presented. In this paper we describe a case study that captured physician preferences for 3-element lists of medical articles in order to learn how to organize medical knowledge for decision-making.

Methods: Comprehensive relevance evaluations were developed to represent 3-element lists of hypothetical articles that may be retrieved from an online medical knowledge source such as MEDLINE or The Cochrane Library. Comprehensive relevance evalua tions asses not only an article’s relevance for a query, but also whether it has been placed on the correct list position. In other words an article may be relevant and correctly placed on a result list (e.g. the most relevant article appears first in the result list), an article may be relevant for a query but placed on an incorrect list position (e.g. the most relevant article appears second in a result list), or an article may be irrelevant for a query yet still appear in the result list. The relevance evaluations were presented to six senior physi cians who were asked to express their preferences for an article’s relevance and its position on a list by pairwise comparisons representing different combinations of 3-element lists. The elicited preferences were assessed using a novel GRIP (Generalized Regression with Intensities of Preference) method and represented as an additive value function. Value functions were derived for individual physicians as well as the group of physicians.

Results: The results show that physicians assign significant value to the 1st position on a list and they expect that the most relevant article is presented first. Whilst physicians still prefer obtaining a correctly placed article on position 2, they are also quite satisfied with misplaced relevant article. Low consideration of the 3rd position was uniformly confirmed.

Conclusions: Our findings confirm the importance of placing the most relevant article on the 1st position on a list and the importance paid to position on a list significantly diminishes after the 2nd position. The derived value functions may be used by developers of clinical decision support applications to decide how best to organize medical knowledge for decision making and to create personalized evaluation measures that can augment typical measures used to evaluate information retrieval systems.