"But 'incurable' does not mean 'untreatable.' We have chemotherapy—FOLFOX or FOLFIRI. We have bevacizumab to block VEGF, stop the angiogenesis. We have immunotherapy if she’s MSI-high. Margaret was MSS—stable. So no magic bullet. But we could buy her time. Good time. Time to see her grandson’s first birthday." Part 5: The Final Chapter (The Autopsy) The last slide is a quote from William Osler: "Medicine is a science of uncertainty and an art of probability."
The autopsy—which I performed—showed a 4 cm liver metastasis that had replaced 60% of her liver parenchyma. The primary colon tumor had perforated silently, walled off by the omentum. And here’s what matters: we found two tiny metastases in her lungs, each 2 mm. Too small to see on CT. That’s why she didn’t respond fully to chemo—the disease was always one step ahead."
"Every cancer begins as a betrayal. In Margaret’s case, the betrayal started in a single crypt cell in her ascending colon. The cause? Sporadic. Bad luck. A base pair mismatch during replication. But one mutation in the APC gene—the 'gatekeeper' of the colon.
Now, Margaret’s tumor has a new skill: angiogenesis. It secretes VEGF, recruiting new blood vessels to feed its growth. The tumor doubles in size. It grows through the muscularis propria—the colon’s own muscle wall. pathology lecture
"At this point, Margaret felt nothing. The polyp was a tiny mushroom growing in the dark. But on a colonoscopy, it would have looked like a raised red bump. If we had caught it then, we would have snip-snipped it out. Case closed. We didn't." Part 2: The Invasion (Breaking the Basement Membrane) An animation shows cells piling up, pushing through a thin blue line (the basement membrane).
Dr. Voss nods slowly. "She knew. She asked me once, over the phone, 'Is it the bad kind?' I told her the truth. She thanked me and said, 'Then I’ll make the most of the time left.'"
Yesterday, I signed out her case. Let’s go back to the beginning." The slide changes. A diagram of a normal colon lining—orderly, like bricks in a wall. "But 'incurable' does not mean 'untreatable
The professor collects her papers.
She died peacefully, at home, with morphine for air hunger and lorazepam for terminal agitation.
"By the time Margaret felt the lump, the primary tumor was already a traitor. It had shed cells into the portal vein. Those cells traveled to the liver—the first filter. Most died there. Immune cells attacked. Shear stress tore them apart. But one cell survived. It was a stem-like cell, adaptable. It landed in the liver sinusoid and whispered to the local macrophages: ‘Don’t attack. I belong here.’ Margaret was MSS—stable
A student in the front row stops taking notes. He’s just staring.
"Good morning. Put down your coffee. This is not a collection of facts. This is a story. The story of a woman named Margaret."
"This is Margaret’s biopsy. See the glands? They’re 'back-to-back'—no normal stroma between them. See the nuclei? They’re hyperchromatic, elongated, stratified. And here—a mitotic figure. That cell is in the middle of dividing wrong.
"This is the moment it becomes malignant. Carcinoma in situ becomes invasive adenocarcinoma. The cells learn to secrete matrix metalloproteinases—molecular scissors. They cut through the collagen. They reach the submucosa. And inside the submucosa are lymphatics and blood vessels.