Tian Zhang, M.D., M.H.S.: Kidney cancer often presents with either direct extension causing pain in the retroperitoneal where the kidneys are located, or if they are big enough and cause damage to the vasculature and cause bleeding in the urine, or what we call hematuria. So pain in the back and blood in the urine are the more likely signs of presentation. If kidney cancer is suspected, patients should expect to undergo imaging studies such as ultrasounds [or] CT scans; even MRIs are being done these days to look at the characteristics of the kidney and the kidney masses. In terms of biomarkers in kidney cancer, we don’t have as many cancer-associated antigens or particular biomarkers that are detectable in the bloodstream. Researchers continue to work on potential screening biomarkers, but unfortunately, none are detectable via the bloodstream.

Chandler H. Park, M.D.: The way kidney cancer is diagnosed, or one of the most common ways people get diagnosed, is if they have any blood in their urine. If you know anybody who has said they have blood in their urine, they have to get that evaluated. Typically we also look for imaging studies such as a CT scan. The CT scan typically shows a mass inside the kidney. Typically the patients notice blood in their urine, or they end up getting a CT scan for some reason; maybe they have flank pain. Flank pain is pain on the left or the right because we have two kidneys. If you have pain on the left side, sometimes people get a scan and the scan shows a mass inside the kidney.

So how do you get the official diagnosis? [For] the official diagnosis, typically the radiologist, the X-ray doctors, talk to us and say, “OK, these spots look suspicious for cancer,” or, “These spots look more like it’s benign.” “Benign” means that it’s not cancer. The term that they use is called “cyst”. And in the radiology report, if they say it’s a cyst, it’s most likely not cancer. And you just do a routine follow-up. But if the radiology scan says something like concern for kidney cancer or they call it polymorphic, which means that it looks like a different appearance, you get a urologist, a surgeon who deals with the kidney on board. They evaluate the imaging, and they decide on surgery or not.

Then the question is: When do you decide whether to do a full kidney removal or a partial? The way to think about a partial is to imagine if you had a bush and you were just pruning one branch of the bush. So that’s technically just removing one little part of the kidney as opposed to taking the whole bush out. If the kidney cancer or the lesion on the scan is less than 4 centimeters, it tends to be at the poles because the kidney is shaped like a kidney bean. So if it’s at the top end of the pole or the lower end of the pole, and it’s less than 4 centimeters, the urologist can take that out, and [the patient] still has the remaining kidney available. So the diagnosis is based on pathology. The reason we tend to get a pathology is if the X-ray doctor or the radiologist says these findings are concerning for kidney cancer based on the morphology and what the cells look like inside the scan.

Transcript is AI-generated and edited for clarity and readability.