The Daily Populous Sunday September 28th, 2025 morning edition
Authored by abc7.com and submitted by l__o-o__l

USC student develops breakthrough app helping doctors treat childhood cancer faster

The 20-year-old developed a software app that computes in minutes what would take radiation oncologists hours to figure out manually.

EAST HOLLYWOOD, LOS ANGELES (KABC) -- Many people dream of doing great things to benefit mankind. One University of Southern California biomedical engineering major wasn't even halfway through college when he developed a software app that significantly improves the way Children's Hospital Los Angeles doctors treat cancer.

While college students are busy learning how the world works, 20-year-old Arjun Karnwal is focused on how to make the world work better.

"I'm always sort of innovation-focused, and I always want to improve things even just by 1%," said Karnwal, a junior at USC's Alfred E. Mann Institute for Biomedical Engineering at the Viterbi School of Engineering.

Even when he attended La Canada High School, Karnwal designed tools to save his teachers' time.

"I used to kind of make websites to help teach classes better," he said.

Now, he's working alongside radiation oncologists at Children's Hospital Los Angeles.

"The question is like, where do we put the radiation to have the best effect?" Karnwal said.

That's what Karnwal is laser-focused on. Radiation doses are referred to as "shots." He invented a software application named "ShotCaller." It computes in minutes what would take doctors hours to figure out manually.

"I think it took us about three to four hours to plan, and with Arjun's algorithm, we were able to come up with a plan in under half an hour," said CHLA radiation oncologist Dr. Kenneth Wong.

When Karnwal came on board as a student volunteer looking for a project, Wong said he asked a lot of questions about the painstaking computations.

"He was able to take our complex ideas and break them down into simpler steps that a computer could follow," Wong said.

Karnwal's app comes into play with a new technique called spatially-fractionated radiation. It's how doctors attack large tumors that don't respond to other treatments. The idea is to find the weak spots that'll shrink the tumor.

"Think of it like you have an Amazon box, and you're trying to pack it full of tennis balls," Karnwal said.

But the math gets more complicated because tumors aren't shaped like rectangles, and doctors have to factor in the spaces needed to avoid healthy tissue and nearby vital organs. Karnwal said it's like fitting as many people as you can into a house, but you have to keep them six feet apart, but then, random furniture gets in the way.

"It gets really complicated when we're worried about three dimensions too," he said.

Karnwal's "ShotCaller" application not only does in minutes what it used to take doctors hours to do, it's even more accurate.

"The ShotCaller algorithm is actually better than our human attempts," said Wong.

Wong said Karnwal's app has eliminated treatment delays and allows his team to efficiently administer a radiation technique that's lengthening lives and reducing pain for his patients.

"We've received a lot of phone calls from centers interested in Arjun's work," he said.

For Karnwal, that's the greatest reward.

"I think it makes all the late nights and early mornings worth it, and I just feel grateful to have the chance to make something," he said.

sandee_eggo on September 28th, 2025 at 04:49 UTC »

You mean the cancer that god gave children? The horrible punishment for being kids? The torture? That cancer?

Nysa_Rayne on September 28th, 2025 at 04:08 UTC »

Yo, mad props to this guy. Straight up genius at work here. Making the world a better place, and dude's not even old enough to legally grab a beer. Goes to show that passion and talent can legit come from anywhere. This is some Tony Stark level stuff fr. Good on ya, Arjun! Peace ✌️