Week 3 - Stevenson T

It took me three weeks, but I was finally able to get into a surgery. I had the good fortune to attend a radical nephrectomy performed by Dr. Doug Scherr from urology. I was putting off going to surgery hoping that I would be able to one/several procedures that were more relevant to my project (as opposed to randomly collecting surgical procedures that often take several hours to complete). As Dr. Scherr is one of the collaborators on my prostate cancer imaging project, this surgery seemed like a good opportunity to meet him. I hope to be able to attend one of his robotic prostatectomy procedures before the end of the immersion term.

Surgery: I was able to observe a radical nephrectomy, during which a kidney is removed as well as some of the surrounding lymph nodes. After the surgery, I was able to go back and look up the symptoms and resulting diagnostics that warranted such a radical surgical intervention. The patient arrived at the hospital complaining of vague abdominal pain which is fairly common and doesn’t usually lead to such a radical procedure, so I felt the need to follow the diagnostic trajectory of the patient. Apparently, one of the first tests done for “vague abdominal pain” is an abdominal CT, which I thought was interesting as it gives the patient a non-trivial amount of radiation exposure. Why not start with ultrasound? Anyway, after determining there was some odd growth/nodule near the apex of the left kidney, the patient then underwent a more expensive/accurate abdominal MRI. This imaging modality revealed a hyper-vascularized growth near the apex of the kidney, extending into the renal vein. Follow up biopsy and histology revealed it to be a adenocarcinoma, a malignant cancerous growth. At this time the patient was probably counseled and decided surgical removal of the affected kidney was the best course of action. Prior to surgical removal of the mass, my mentor’s dept (nuclear medicine) came into the picture. To help determine the extent of the growth into the renal vein, and possible to locate large metastatic masses, nuclear medicine did a {¹⁸F}-FDG PET/CT to highlight areas in the body that contained unusually high levels of glycolytic metabolism. The imaging revealed a very long invasion into the renal vein, which changed the “plan of attack” for the surgery. Normal nephrectomies are performed with the patient lying on his/her stomach, to allow for easy access to the kidneys. Because of the large invasion into the renal veins, Dr.Scherr was probably going to have to go on a “hunt” for the end of the cancerous growth, which may have required moving across the patients central plane of symmetry (in other words, he’d have to dig around in both parts of the patients abdominal cavity looking for the end of the growth into the renal vein). I was amazed at the number of high-tech imaging and diagnostic procedures that were performed leading up to the decision of a surgical intervention and sort of shocked at the crudeness of the actual surgical procedure. Other than the electrical cutting tools, most of the surgical instruments could’ve been from 50-100years ago. We were already labeling the tumor for PET, couldn’t it have been labeled with some gamma emitter? The surgeon would’ve been able to use a surgical Geiger counter to help locate/localize the growth into the renal vein….

Research: This week I spent a good deal of research time collecting and organizing data from a previous clinical study. This earlier study used an [¹¹¹In] labeled antibody J591 to specifically image prostate cancer. J591 binds specifically to Prostate Specific Membrane Antigen (PSMA) with high affinity. These indium labeled antibodies are administered to patients two days before they go into surgery for a complete prostatectomy. After the prostate is removed it is imaged ex vivo using a clinical SPECT. I collected patient data and images for 7 patients, and compiled them into a single database. We will be using this database to compare previous imaging results J591 to small molecule imaging agents.