Hello Health Rounds readers! We've got one more study from the just-concluded American Society of Clinical Oncology meeting in Chicago to report and it's a potential game-changer for certain colon cancer patients. We also highlight a study that could change clinical recommendations following a common heart procedure and one on possible eye risk linked to GLP-1 drugs.

In breaking news, see these stories from our Reuters journalists: US Health Secretary Kennedy looks to fast-tracking approvals for rare disease drugs; CDC official resigns from COVID vaccine committee advisory role; surge in new opioids and designer drugs threatens Europe; thousands of lawsuits over baby formula should stay where filed; and US faces vape shortage as tariffs, seizures hit Geek Bar.

Also: Canada's Ontario province reports death of child from measles; Chile abortion rights bill could shape President Boric's legacy; Indonesian policyholders must pay part of medical insurance claims from 2026 and China's Sichuan province to offer extended marriage and maternity leave.

When President Donald Trump banned nationals from 12 countries, including Afghanistan, from entering the United States, he shattered the dreams of women who were waiting for visas after working for decades for U.S.-funded projects in Afghanistan.  

Adding Roche's immunotherapy drug Tecentriq to chemotherapy after surgery in certain patients whose colon cancer had spread to the lymph nodes led to a 50% reduction in cancer recurrence and death compared to chemotherapy alone, according to trial data presented at recent medical meeting.

Patients in the study had tumors with a genetic defect known as deficient DNA mismatch repair, or dMMR. About 15% of colon cancer patients have dMMR tumors, which do not respond well to chemotherapy.

"The findings from our study represent a major advance in the adjuvant treatment of dMMR stage 3 colon cancer and will now change the treatment for this type of cancer," study leader Dr. Frank Sinicrope of the Mayo Clinic in Rochester, Minnesota said in a statement.

The data were presented at the ASCO 2025 meeting that concluded earlier this week.

The trial enrolled 712 patients with dMMR stage 3 colon cancer that had been surgically removed and who had cancer cells in their lymph nodes.

Half of the study participants received chemotherapy along with Tecentriq, which activates the immune system to attack and kill cancer cells, for six months, followed by the immunotherapy alone for another six months.

The other half of the patients received chemotherapy for 12 months.

The benefit of Tecentriq was seen even in the oldest patients and those at particularly high-risk.

"It's extremely rewarding to be able to offer our patients a new treatment regimen that can reduce the risk of recurrence and improve their chances of survival," Sinicrope said.

As patients recover after a minimally invasive heart procedure, they might be better off continuing to take a certain type of blood-thinning drug to help prevent a heart attack or stroke, instead of continuing with the traditional aspirin, a new study suggests.

Early after percutaneous coronary intervention (PCI) - a procedure to prop open blocked arteries either after a heart attack, or to prevent one - patients often receive dual anti-clotting therapy with both a P2Y12 inhibitor such as clopidogrel, the generic version of Plavix, or AstraZeneca's Brilinta (ticagrelor), and aspirin. After several months, patients are usually switched from dual therapy to lifelong daily aspirin use.

But pooled data looking at patients who took part in five earlier clinical trials found that continuing to prescribe the P2Y12 inhibitors and stopping the aspirin was associated with lower rates of death, heart attack and stroke compared with continuing the aspirin, with no increased risk of major bleeding, researchers reported in The BMJ.

Overall, the trials involved 16,117 patients who received either a P2Y12 inhibitor or aspirin after completing dual therapy following PCI.

After an average follow-up period of around 4 years, P2Y12 inhibitor therapy was associated with a 23% lower risk of a composite of heart-related death, heart attack, or stroke, compared with aspirin, with no significant difference in major bleeding.

That translates into one prevented cardiovascular death, heart attack, or stroke for every 46 patients taking a P2Y12 inhibitor instead of aspirin after dual therapy.

Overall, the findings suggest that P2Y12 inhibitor drugs should be preferred over aspirin “due to reductions in major adverse cardiac and cerebrovascular events without increasing major bleeding in the medium term,” according to an editorial published with the study.

But the editorial said that since patients are advised to continue the post-PCI therapy for life, large trials directly comparing the different strategies with longer follow up are needed.

Some diabetes and weight-loss drugs from the class known as GLP-1 agonists were linked with a small but elevated risk for an age-related eye disease in patients with diabetes, according to a study published on Thursday in JAMA Ophthalmology.

In 139,000 patients with diabetes, including 46,334 who had been using the GLP-1 drugs semaglutide or lixisenatide, researchers identified 181 new cases of neovascular age-related macular degeneration, also known as wet AMD.

Wet AMD is a degenerative eye disease marked by the abnormal growth of blood vessels under the retina that leak fluid or blood and can lead to blindness.

The risk of developing AMD during up to three years of follow-up was low, at 0.2% in GLP-1 users versus 0.1% in non-users.

Still, the researchers point out, after accounting for patients’ individual risk factors, the odds of AMD were doubled with at least six months of GLP-1 use and tripled in patients with the longest duration of use.

Semaglutide is the active ingredient in the widely used Novo Nordisk drugs Ozempic and Wegovy, while lixisenatide is the main ingredient in Sanofi's discontinued Adlyxin. 

GLP-1 drugs have also been associated with higher risks for an eye condition known as nonarteritic anterior ischemic optic neuropathy, or NAION.

Researchers did not have information about the dose, route of administration, or frequency of administration of the medications used in the study. Even with that information, the study could not have proved cause and effect.

At least one earlier study with longer follow up reported that GLP-1 use was linked with a lower, rather than higher, risk for AMD.