Chai with Scintillating Stars: A Conversation with Dr. Ashok Muthu Krishnan: Reimagining the Future of Theranostics

Chai with a Scintillating Star
Dr. Ashok Muthu Krishnan: Reimagining the Future of Theranostics
A conversation on innovation, mobile theranostics, multidisciplinary care, technology, and the human side of medicine

Guest: Ashok Muthu Krishnan, MD
Founder & Chief Physician, Florida Theranostics
Nuclear Oncologist & Molecular Imager
Director of Theranostics

Hosts: Amol M. Takalkar, MD, MS, MBA, FACNM — Past President, IASNM
Vikas Prasad, MD, PhD, FEBNM, DNB — Board of Directors Member, IASNM

From Pondicherry to the forefront of theranostics
In this episode of Chai with a Scintillating Star, IASNM hosted Dr. Ashok Muthu Krishnan, a physician whose career reflects the remarkable evolution of nuclear medicine itself.
From his roots in Pondicherry, India, to CMC Vellore, Birmingham, Pittsburgh, and ultimately Jupiter, Florida, Dr. Krishnan’s journey has been shaped less by a predetermined master plan and more by curiosity, opportunity, and a willingness to walk through doors when they opened.
Reflecting on his journey, he describes each chapter as having given him something different.
Pondicherry gave him his roots. Birmingham helped him find his place in medicine in the United States. Pittsburgh exposed him to academic medicine and advanced technology. And Jupiter gave him the opportunity to take what he had learned and build something of his own.
That philosophy ultimately became central to his decision to establish Florida Theranostics.
For Dr. Krishnan, the journey remains very much in progress.

Theranostics: From promise to clinical reality
The conversation quickly turned to one of the most transformative developments in nuclear medicine: the rapid growth of molecular imaging and radiopharmaceutical therapy.
Dr. Krishnan sees the current evolution as the convergence of several powerful forces.
The clinical success of radiopharmaceutical therapies such as Lutathera and Pluvicto has changed the way oncology views nuclear medicine. At the same time, the therapeutic pipeline continues to expand, with new molecular targets, alpha emitters, beta therapies, combination approaches, and applications moving into earlier stages of disease.
Technology is advancing just as rapidly. Digital PET/CT, long axial field-of-view systems, CZT technology, quantitative SPECT, improved reconstruction algorithms, sophisticated software, and advances in dosimetry are collectively opening new possibilities.
These developments, Dr. Krishnan believes, may gradually move the field away from a predominantly fixed-dose approach toward increasingly individualized treatment strategies.
But perhaps the most important transformation is not technological. It is the changing relationship between nuclear medicine and the patient.
Historically, nuclear medicine physicians often functioned primarily as consultants. Theranostics has changed that paradigm. Today, nuclear medicine physicians may see the patient, participate in patient selection, administer therapy, manage aspects of treatment, evaluate toxicity, and assess treatment response.
The nuclear medicine physician is increasingly becoming what Dr. Krishnan calls a “theranostician” — someone working at the intersection of molecular imaging and therapy.

When science becomes personal
What made Dr. Krishnan passionate about theranostics? For him, the answer goes beyond technology.
Nuclear medicine has long possessed the scientific foundations of precision medicine: identify a molecular target, image its expression throughout the body, and potentially use that same target to deliver radiation selectively to disease sites.
But the science became truly meaningful when it reached the patient’s bedside.
Dr. Krishnan recalls the experience of caring for patients with advanced cancer who have already undergone multiple treatments and being able to offer another meaningful therapeutic option based on something visible on their molecular imaging.
At that point, theranostics becomes more than an elegant scientific concept. It becomes a relationship.
Patients return for subsequent treatment cycles. Physicians meet their spouses and families. They experience the patient’s good days as well as their difficult days.
For Dr. Krishnan, that human connection transformed his understanding of nuclear medicine.
Taking Theranostics to the Patient
One of the most innovative ideas discussed during the conversation was Dr. Krishnan’s mobile theranostics unit.
The concept began with a straightforward observation: patients are not always located where theranostics infrastructure exists.
A community oncologist may be providing excellent care, but establishing a complete radiopharmaceutical therapy program requires significant infrastructure, including licensing, authorized users, trained staff, radiation safety protocols, treatment space, radioactive material handling and storage, and waste management.
For a facility treating only a few patients each month, building an entire program may not be practical.
That led Dr. Krishnan to ask a different question: “Does the infrastructure always have to be fixed?”
Rather than continually moving patients toward specialized infrastructure, could some of that infrastructure move toward the patient?
That question became the foundation of his mobile theranostics model.
He describes it as a hub-and-spoke model: a specialized theranostics center can provide expertise, personnel, regulatory oversight, and treatment infrastructure while partnering with community oncology programs closer to where patients live.
Innovation requires rigorous preparation

With innovation comes responsibility.
The regulatory and radiation-safety considerations associated with a mobile theranostics model are substantial.
Dr. Krishnan emphasized that a fixed-center workflow cannot simply be placed on wheels.
The program must address radioactive material licensing and possession, transportation, Authorized User responsibilities, vehicle security, administration procedures, contamination control, surveying, radioactive waste, and patient release.
It must also anticipate unexpected situations.
What happens if a patient develops a medical emergency shortly after therapy? What happens if a patient does not meet release criteria? How is the patient safely transferred to an emergency department? How are radiation-safety precautions communicated to the receiving medical team?
These scenarios need to be anticipated and incorporated into formal protocols.
For Dr. Krishnan, radiation safety was not an afterthought; it was an integral part of the architecture of the program from day one.
His experience also reinforced an important lesson about innovation: unconventional ideas require exceptionally careful preparation.

The Patient Must Remain at the Center
Another major theme of the conversation was collaboration.
As theranostics expands, Dr. Krishnan believes it cannot successfully develop as an isolated branch of nuclear medicine.
The patient does not belong exclusively to nuclear medicine, medical oncology, radiation oncology, or urology. The patient belongs at the center.
Each specialty contributes a different form of expertise.
Medical oncologists bring an understanding of the longitudinal course of disease, systemic therapies, sequencing, toxicity, and combination strategies.
Radiation oncologists contribute expertise in radiation biology, absorbed dose, normal tissue tolerance, and treatment planning.
Nuclear medicine brings molecular imaging, radiopharmaceutical biology, whole-body assessment of target expression, radionuclide handling, dosimetry, and the ability to use imaging to select, treat, and subsequently evaluate patients.
Rather than viewing these disciplines as competing, Dr. Krishnan sees them becoming increasingly interdependent.
He envisions future theranostics programs functioning more like multidisciplinary tumor boards than isolated treatment services.
The questions will become increasingly sophisticated: When is the optimal time to use a radiopharmaceutical therapy? What treatment should precede it? What should follow it? When should external-beam radiation be considered? How might systemic therapy or immunotherapy be integrated? Can imaging and dosimetry help personalize treatment?
These questions cannot be answered by a single specialty. They require collaboration.
Looking Back: Worry Less, Take Risks Earlier
When asked what he would do differently if he could revisit his career, Dr. Krishnan’s answer was surprisingly simple: “I would probably worry less.”
Early in a career, it is easy to spend enormous amounts of energy wondering whether a decision is the right one. Looking back, Dr. Krishnan says that many of the things that seemed important at the time turned out to be relatively unimportant.
Some setbacks that initially seemed terrible ultimately pushed him toward opportunities that were better suited to him.
He would also take certain professional risks earlier.
One does not need to know everything before starting something new. What matters is understanding the most important elements, surrounding yourself with people who know what you do not know, and being willing to learn quickly.
But another lesson became even more important with time: protect time for the people you love.
Medicine can consume as much of one’s life as one allows it to. There will always be another program to build, another scanner to purchase, another project to start.
But there is one resource that cannot be recreated: time.

The Creative Side of a Nuclear Medicine Physician
Away from medicine, Dr. Krishnan describes himself as deeply curious about technology and design.
He is fascinated by what happens when medicine intersects with engineering, architecture, computing, and art.
Travel is another passion, exposing him to different cultures, architecture, food, and ways of thinking. He is also interested in music and increasingly in the design of healthcare environments.
Patients arriving for cancer imaging or treatment may already be anxious. Architecture, ambient lighting, sound, technology, and art can all influence how patients experience their care environment.
Ultimately, however, what he enjoys most is creating — whether it is a clinical program, a physical space, a technology, or simply an idea that did not previously exist.
Advice to the Next Generation
The conversation concluded with a message for residents, fellows, and young physicians entering nuclear medicine.
Dr. Krishnan believes they have chosen the field at an extraordinary moment. The nuclear medicine of today is already dramatically different from the field he entered, and he believes the transformation is only beginning.
His advice is therefore not simply to master today’s nuclear medicine. It is to prepare for tomorrow’s.
Learn molecular biology. Understand oncology. Learn dosimetry and radiation biology. Understand physics and instrumentation. Learn how clinical trials work. Increasingly, understand computation and artificial intelligence as they come into medicine.
But technical expertise alone is not enough.
The newest scanner or radiopharmaceutical may be exciting to the physician. For the patient sitting across the room, however, cancer treatment may represent one of the most frightening periods of their life.
Technical excellence and compassion are not opposing qualities. You should aspire to have both.
And finally, remain curious.

Some of the most important opportunities in Dr. Krishnan’s career came from asking simple questions: Why do we do it this way? Does it have to be this way? What would happen if we tried something different?
Sometimes the answer will be wrong. That is okay. Learn, adjust, and keep moving forward.

A Future Built on Curiosity
The conversation with Dr. Ashok Muthu Krishnan offers a glimpse into a specialty undergoing profound transformation.
Theranostics is changing the role of nuclear medicine from primarily diagnostic imaging toward an increasingly integrated discipline combining molecular imaging, targeted therapy, dosimetry, technology, oncology, and patient care.
But perhaps the most enduring message from the conversation is not about a new radiopharmaceutical, scanner, or treatment model.

It is about curiosity.
Curiosity to ask whether infrastructure can move to the patient.
Curiosity to question established workflows.
Curiosity to explore the intersection of medicine and design.
Curiosity to build something that does not yet exist.
And, most importantly, curiosity that never loses sight of the person at the center of it all.
As Dr. Krishnan put it, the next generation of nuclear medicine physicians may take the specialty much further than the current generation ever imagined.
Perhaps that is the real promise of theranostics — not simply a new chapter in nuclear medicine, but an opportunity to rethink what nuclear medicine can become.

Quotes to Highlight
“Starting something new is not necessarily something to fear.”
“The patient belongs at the center.”
“Rather than asking who should own theranostics, we should be asking, how do we build the best multidisciplinary team around theranostics?”
“Time is the only thing that you cannot build again.”
“You should aspire to have both — technical excellence and compassion.”

About Chai with a Scintillating Star
Chai with a Scintillating Star is an IASNM conversation series featuring inspiring physicians and leaders who are contributing to the evolution of nuclear medicine, molecular imaging, and theranostics.
IASNM — Indo-American Society of Nuclear Medicine