In a prospective cohort study reported in The Lancet, Knight et al found that 30-day mortality after surgery for colorectal and gastric cancers was higher in low- and middle-income countries vs high-income countries (LMICs), with the difference only partly accounted for by patient or disease factors.

The study was performed by the GlobalSurg Collaborative and National Institute for Health Research Global Health Research Unit on Global Surgery.

Study Details

The study compared postoperative outcomes in 15,958 patients from 428 hospitals in 82 countries who underwent surgery for primary breast, colorectal, or gastric cancers, with enrollment occurring between April 2018 and January 2019. The population consisted of 9,106 patients from 31 high-income countries (World Bank classification), 2,721 patients from 23 upper middle–income countries, and 4,131 patients from 28 lower middle–income countries. The primary outcome was death or major complication within 30 days of surgery. Adjusted odds ratios (ORs) for outcomes were determined in multilevel logistic regression analysis.

30-Day Major Complication and Mortality Rates

Patients in LMICs were more likely to present with more advanced disease vs those in high-income countries. Hospitals in upper middle–income and low- or lower middle–income countries were less likely to have postoperative care infrastructure (eg, designated postoperative recovery areas, consistently available critical care facilities, and available functioning computed tomography) and cancer care pathways (eg, tumor boards, oncology services, and palliative care services).

Among 1,337 patients undergoing surgery for gastric cancer, no significantly increased risk of 30-day major complications was observed among LMICs vs high-income countries. Mortality was significantly higher in low-income or lower middle­­–income countries (OR = 3.72, 95% confidence interval [CI] = 1.70–8.16).

Among 6,215 patients undergoing surgery for colorectal cancer, no significantly increased risk of 30-day major complications was observed among LMICs vs high-income countries. Mortality was higher in low-income or lower middle–income countries (OR = 4.59, 95% CI = 2.39–8.80) and upper middle­–income countries (OR = 2.06, 95% CI = 1.11–3.83).

Among 8,406 patients undergoing surgery for breast cancer, risk of 30-day major complications was reduced in upper middle–income countries vs high-income countries (OR = 0.53, 95% CI= 0.31–0.90). No significant difference in mortality was observed among LMICs vs high-income countries. 

Risk of Death After Major Complications

In a model in the total population accounting for patient factors and clustering by country and hospital, patients in upper middle–income (OR = 3.89, 95% CI = 2.08–7.29) and low-income or lower middle–income groups (OR = 6.15, 95% CI = 3.26–11.59) had a significantly increased risk of dying after major complications vs the high-income group. Patients with stage IV cancer had a greater likelihood of dying after major complications; however, stage I to III cancer was not associated with excess mortality when accounting for other variables.

In a model of patients nested in hospitals, countries, and income groups, 60% of the variation in mortality outcome was explained by patient or disease factors, and 40% by hospital, country, and country income group factors.

A model including postoperative care infrastructure showed that a significant proportion of excess mortality was associated with absence of postoperative care infrastructure in low-income or lower middle–income (OR = 1.19, 95% CI = 1.01–1.42; 20%) and upper middle–income groups (OR = 1.19, 95% CI = 1.01–1.42; 22%). Additional analysis showed that presence of postoperative care infrastructure in the low-income or lower middle–income group (7–10 fewer deaths/100 major complications, number needed to treat = 10–14) and the upper middle–income group (5–8 fewer deaths/100 major complications, number needed to treat = 13–20) was associated with reduced mortality after major complications.

The investigators concluded, “Higher levels of mortality after cancer surgery in LMICs was not fully explained by later presentation of disease. The capacity to rescue patients from surgical complications is a tangible opportunity for meaningful intervention. Early death after cancer surgery might be reduced by policies focusing on strengthening perioperative care systems to detect and intervene in common complications.”

Ewen M. Harrison, PhD, of the University of Edinburgh, is the corresponding author for The Lancet article.

Disclosure: The study was funded by the National Institute for Health Research Global Health Research Unit. For full disclosures of the study authors, visit thelancet.com.