Variation in receipt of therapy and survival with provider volume for medical oncology in non-curative esophago-gastric cancer: a population-based analysis

  • Julie HalletEmail author
  • Laura E. Davis
  • Alyson L. Mahar
  • Ying Liu
  • Victoria Zuk
  • Vaibhav Gupta
  • Craig C. Earle
  • Natalie G. Coburn
Original Article



While surgical care by high-volume providers for esophago-gastric cancer (EGC) yields better outcomes, volume–outcome relationships are unknown for systemic therapy. We examined receipt of therapy and outcomes in the non-curative management of EGC based on medical oncology provider volume.


We conducted a population based retrospective cohort study of non-curative EGC over 2005–2017 by linking administrative healthcare datasets. The volume of new EGC consultations per medical oncology provider per year was calculated and divided into quintiles. High-volume (HV) medical oncologists were defined as the 4–5th quintiles. Outcomes were receipt of chemotherapy and overall survival (OS). Multivariate logistic and Cox-proportional hazards regressions examined the association between management by HV medical oncologist, receipt of systemic therapy, and OS.


7011 EGC patients with non-curative management consulted with medical oncology. 1-year OS was superior for HV medical oncologists (> 11 patients/year), with 28.4% (95% CI 26.7–30.2%) compared to 25.1% (95% CI 23.8–26.3%) for low volume (p < 0.001). After adjusting for age, sex, comorbidity burden, rurality, income quintile, and diagnosis year, HV medical oncologist was independently associated with higher odds of receiving chemotherapy (OR 1.13, 95% CI 1.01–1.26), and independently associated with superior OS (HR 0.89, 95% CI 0.84–0.93).


Medical oncology provider volume was associated with variation in non-curative management and outcomes of EGC. Care by an HV medical oncologist was independently associated with higher odds of receiving chemotherapy and superior OS, after adjusting for case mix. This information is important to inform disease care pathways and care organization; an increase in the number of HV medical oncologists may reduce variation and improve outcomes.


Esophagus Stomach Cancer Outcomes Volume 



This study was supported by the Canadian Institute of Health Research (FRN #154131) and the Sherif and Mary-Lou Hanna Chair in Surgical Oncology Research. This study was supported by ICES, which is funded by an annual grant from the Ontario Ministry of Health and Long-Term Care (MOHLTC). The opinions, results and conclusions reported in this paper are those of the authors and are independent from the funding sources. No endorsement by ICES or the Ontario MOHLTC is intended or should be inferred. Parts of this material are based on data and information compiled and provided by CIHI. However, the analyses, conclusions, opinions, and statements expressed herein are those of the author, and not necessarily those of CIHI. Parts of this material are based on data and information provided by Cancer Care Ontario (CCO). The opinions, results, view, and conclusions reported in this paper are those of the authors and do not necessarily reflect those of CCO. No endorsement by CCO is intended or should be inferred.


This study was supported by the Canadian Institute of Health Research (FRN #154131).

Compliance with ethical standards

Conflict of interest

Julie Hallet has received speaking honoraria from Ipsen Biopharmaceuticals Canada and Novartis Oncology. Natalie Coburn receives salary support from Cancer Care Ontario as the Clinical Lead of Patient Reported Outcomes and Symptom Management. Laura Davis declares that she has not conflict of interest. Alyson Mahar declares that she has not conflict of interest. Ying Liu declares that she has not conflict of interest. Vaihbav Gupta declares that he has not conflict of interest. Craig Earle declares that he has not conflict of interest.

Ethical approval

All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.

Informed consent

Informed consent was waived by the Sunnybrook Health Sciences Centre Research Ethics Board, for the conduct of population-based analysis.

Supplementary material

10120_2019_1012_MOESM1_ESM.pdf (243 kb)
Supplementary file1 (PDF 243 kb)


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Copyright information

© The International Gastric Cancer Association and The Japanese Gastric Cancer Association 2019

Authors and Affiliations

  • Julie Hallet
    • 1
    • 2
    • 3
    • 4
    Email author
  • Laura E. Davis
    • 3
  • Alyson L. Mahar
    • 5
  • Ying Liu
    • 4
  • Victoria Zuk
    • 3
  • Vaibhav Gupta
    • 2
  • Craig C. Earle
    • 4
    • 6
  • Natalie G. Coburn
    • 1
    • 2
    • 3
    • 4
  1. 1.Division of Surgical OncologyOdette Cancer Centre-Sunnybrook Health Sciences CentreTorontoCanada
  2. 2.Department of SurgeryUniversity of TorontoTorontoCanada
  3. 3.Sunnybrook Research InstituteTorontoCanada
  4. 4.ICESTorontoCanada
  5. 5.Department of Community Health SciencesUniversity of ManitobaWinnipegCanada
  6. 6.Division of Medical OncologyOdette Cancer Centre-Sunnybrook Health Sciences CentreTorontoCanada

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