One in seven cancer patients around the world have missed out on potentially life-saving operations during COVID-19 lockdowns, a new study reveals.

Led by experts at the UK's University of Birmingham, almost 5,000 surgeons and anaesthetists from around the world worked together to analyse data from the 15 most common solid cancer types in 20,000 patients across 466 hospitals in 61 countries. The team published its findings in The Lancet Oncology.

Researchers analysed data from adult patients suffering from cancer types including colorectal, oesophageal, gastric, head and neck, thoracic, liver, pancreatic, prostate, bladder, renal, gynaecological, breast, soft-tissue sarcoma, bony sarcoma, and intracranial malignancies.

They found planned cancer surgery was affected by lockdowns regardless of the local COVID-19 rates at that time, with patients in lower-income countries at the highest risk of missing their surgery. During full lockdowns, one in seven patients (15 per cent) did not receive their planned operation after a median of 5.3 months from diagnosis all with a COVID-19 related reason for non-operation. However, during light restriction periods, the non-operation rate was very low (0.6 per cent).

"Our research reveals the collateral impact of lockdowns on patients awaiting cancer surgery during the pandemic. Whilst lockdowns are critical to saving lives and reducing the spread of the virus, ensuring capacity for safe elective cancer surgery should be part of every country's plan to ensure continued health across the whole population," said James Glasbey, from the University of Birmingham.

"In order to prevent further harm during future lockdowns, we must make the systems around elective surgery more resilient protecting elective surgery beds and operating theatre space, and properly resourcing 'surge' capacity for periods of high demand on the hospital, whether that is COVID, the flu or other public health emergencies," he added.

While the study only followed patients that underwent a delay for a short period of time, evidence from other research suggests that these patients may be at higher risk of recurrence. "To help mitigate against this, surgeons and cancer doctors should consider closer follow-up for patients that were subject to delays before surgery," Aneel Bhangu, from the University of Birmingham, said.