Notes From Between Answers
/There is a hospital that I can see from my front yard.
From the hill where I live in San Francisco’s Presidio, the University of California, San Francisco rises quietly above the rooftops on another hill across the city. Most mornings it’s simply part of the skyline, standing in the distance as the fog drifts inland from the Pacific Ocean. Over the years I’ve grown strangely fond of that view, not because it’s dramatic, but because it quietly reminds me where one of the most important chapters of my life began.
On the morning of June 17, 2026, I found myself looking toward that hill once again.
If you’ve followed my astrocytoma blog posts over the past few years, you probably know that MRI machines and I have never become close friends. The loud knocking sounds, the narrow tube, and the strange feeling of lying perfectly still while your imagination insists on wandering somewhere else aren’t experiences I’ve ever learned to enjoy.
Oddly enough, though, the MRI itself has never been the part that frightened me most.
For years, waiting for the results never really bothered me.
That probably sounds strange coming from someone who was diagnosed with a Grade 3 IDH-mutant astrocytoma, but a lot has changed since the terrifying weeks that followed my diagnosis in 2021.
Back then, I honestly believed my future had already been written.
My first neuro-oncologist painted a picture that left me feeling hopeless. I left those appointments believing that my brain tumor would be back and simply continue growing until one day there would be nothing left to do. Every conversation seemed to revolve around statistics, recurrence, and preparing for the inevitable. It was difficult to imagine a future beyond treatment because no one seemed interested in talking about one.
Thankfully, that wasn’t where my story ended.
Not long afterward, I transferred my care to another neuro-oncology team at UCSF, and everything changed. The difference wasn’t that they promised miracles but the difference was that they understood something I’d desperately needed to hear.
That simple change in perspective transformed the way I looked at my own diagnosis.
Over the next four and a half years, I found myself becoming fascinated by the science behind everything I had gone through. What began as a desperate attempt to understand my own pathology gradually became late nights reading medical journals, watching physician lectures, learning about molecular genetics, radiation biology, and the remarkable discoveries that continue reshaping neuro-oncology.
Somewhere along the way I realized something unexpected. Learning had quietly replaced fear.
That curiosity eventually became AstroCare Companion AI, a public educational resource I built to help patients and families better understand astrocytoma without having to spend hundreds of hours sorting through medical papers the way I had. It was never meant to replace physicians. If anything, it made me appreciate good physicians even more. The better I understood the science, the better conversations I was able to have with my own doctors.
By the time this appointment arrived, my routine had become almost predictable.
Every six months I’d make the same walk across San Francisco, spend far too long inside an MRI scanner, meet with my neuro-oncologist, and then walk home grateful life could continue as usual. This appointment began exactly the same way, except a month earlier my doctor had asked me to return much sooner than expected.
But there was enough uncertainty that he wanted another look but not another MRI six months later.
One of the most valuable lessons I’ve learned over the past several years is that medicine often lives somewhere between certainty and uncertainty. Patients naturally want definitive answers, but physicians spend much of their careers learning how to navigate the gray space in between. Sometimes another scan isn’t ordered because something terrible has happened.
Sometimes it’s ordered because good medicine refuses to guess.
That thought stayed with me as I left my apartment and began the familiar walk toward UCSF.
Living in the Presidio gives me a perspective on San Francisco that still feels unusual, even after all these years. Towering eucalyptus trees give way to quiet neighborhoods before opening into Golden Gate Park, where museums, gardens, runners, cyclists, and tourists somehow all coexist without ever seeming to get in each other’s way.
I’ve walked this route so many times that I know it almost by memory.
Yet every appointment somehow changes the walk.
This particular morning I wasn’t rehearsing questions for my doctor or trying to predict what he might say. Instead, I found myself paying attention to little things I’d normally pass without a second thought. The smell of the trees after the morning fog or the familiar paths winding through Golden Gate Park or families beginning their day while mine revolved around another MRI.
Funny how perspective works. The same city can feel completely different depending on where your thoughts happen to be.
It was somewhere along that walk that something caught my attention. Nestled tightly between two much larger buildings sat a bright yellow house that looked almost as though the neighborhood had slowly grown up around it over the decades. Sitting out front was a Little Free Library.
Inside my backpack were several copies of books from The Amaranth Chronicles, the science fiction universe I’ve spent years building alongside friends and collaborators. I hadn’t planned on leaving them anywhere that morning, but standing there in front of that tiny library it suddenly felt like the right thing to do. One by one I placed the books on its shelves, wondering who might eventually stumble across them.
Looking back, I don’t think I was trying to promote my work as much as I was reminding myself that uncertainty doesn’t take away every choice we have. I couldn’t control what my MRI would show, and I certainly couldn’t influence what my doctor was about to tell me later that afternoon. But I could leave behind a few stories that had meant something to me, quietly waiting for someone else to discover them. Somehow that small act made the rest of the walk feel a little lighter.
I adjusted my backpack and started the final climb toward UCSF, completely unaware that before the day was over I’d find myself disappearing down one of the most fascinating scientific rabbit holes I’ve explored for years now.
It all started with four simple words.
“We should order a PET scan.”
My neuro-oncologist has a way of delivering information that I’ve come to appreciate over the years. He never rushes toward the worst-case scenario, nor does he dismiss uncertainty simply because there isn’t an immediate answer. Instead, he studies the evidence, explains what he sees, and calmly walks through the possibilities. After years of working together I’ve learned that sometimes what matters most isn’t simply what a physician knows, it’s how they think.
When he opened my latest MRI, two images appeared side by side on the screen. One had been taken only a few weeks earlier, while the other had been taken the previous day. He pointed toward a small area away from where my original tumor had been removed and explained that it appeared to have changed slightly since my previous scan. This wasn’t a new conversation. We’d actually been watching that same region for years because it had always behaved much more like treatment-related change than recurrent tumor, something that can happen after brain surgery and radiation therapy.
Radiation is remarkably effective at destroying cancer cells, but it doesn’t distinguish perfectly between healthy tissue and tumor. Occasionally the surrounding brain responds years later in ways that can resemble tumor growth on an MRI even when cancer isn’t returning. From what he could see, he still believed that was the most likely explanation, which was certainly reassuring, but it wasn’t enough to completely answer the question.
“So,” he said, “I’d like to order a PET scan.”
Those four words immediately sent my curiosity in a completely different direction.
I knew what a PET scan was in the most general sense. Like most people, I’d heard the term before. I knew it involved some kind of radioactive tracer and that doctors often used it to look for cancer. That was about the extent of my knowledge. After everything I’d learned over the past four and a half years, that realization actually surprised me. I’d spent hundreds of hours reading about IDH mutations, MGMT methylation, awake brain surgery, radiation therapy, chemotherapy, stroke risk, seizures, genetics, molecular biology, and artificial intelligence, yet somehow I’d reached this point knowing almost nothing about one of the most important imaging technologies in modern medicine.
As I walked home through Golden Gate Park, I couldn’t stop thinking about it. Not because I was afraid of the scan, but because I wanted to understand it. That’s become something of a pattern in my life. Whenever medicine introduces me to something unfamiliar, I almost instinctively start asking questions. How does it work? Why was it invented? What problem was it trying to solve? Who figured this out in the first place?
At first, I expected to learn about another medical machine but Instead, I found myself watching videos about particle physics.
The more I learned about PET scans, the more I realized they weren’t simply taking photographs of the body, they were observing tiny events happening at the atomic level and… the best part?
ANTI-MATTER
YES. You read that right.
Anti-matter sounds like it belongs in science fiction but growing up with Star Trek, I associated antimatter with starships, warp engines, and impossible amounts of energy. I never imagined it was real and used in the medical industry.
During a PET scan, a tiny amount of radioactive material is introduced into the body. As that material naturally decays, it releases particles called positrons. A positron is essentially the antimatter counterpart of an electron. When a positron encounters an electron inside your body, the two particles annihilate one another almost instantly, releasing two gamma rays that travel in opposite directions.
Those gamma rays aren’t dangerous explosions or anything dramatic like science fiction often portrays. They’re tiny signals that an incredibly sophisticated scanner can detect. By measuring millions of those events, computers reconstruct a remarkably detailed picture showing how different parts of the body are functioning.
I sat there for several minutes simply thinking about that.
Somewhere inside my own brain, particles that exist for only unimaginably brief moments could help physicians distinguish between radiation-related changes and something far more concerning.
The same universe that inspired decades of science fiction was quietly helping doctors understand my disease without making a single incision.
As both a science fiction author and a brain cancer survivor…. I love this idea.
The more I learned about PET imaging, the more I found myself appreciating another technology that has quietly become part of my own journey.
Over the last several years, AI has become one of the ways I organize what I’m learning. Not because I expect it to replace physicians, but because it helps me understand them. I’ll ask it to explain a paragraph from a research paper in simpler language, compare two studies that appear to disagree, define unfamiliar medical terminology, or help me think of better questions before my next appointment. The answers themselves aren’t the goal. Understanding enough to have a meaningful conversation with my doctors is.
That realization eventually led me to create AstroCare Companion AI.
I wasn’t trying to build a doctor inside a computer. I was trying to build the resource I wish I’d had after my own diagnosis. Something that could help patients and families better understand complicated terminology, summarize new research, explain why certain treatments are recommended, and prepare people to have more informed conversations with their own medical teams. If it encourages someone to ask one thoughtful question they might not have known to ask otherwise, then I think it’s already served its purpose.
