Published on September 1, 2021
How Is Advanced Prostate Cancer Diagnosed?
What is involved in obtaining a correct advanced prostate cancer diagnosis? Listen in as Vivek Narayan, MD, MSCE, Assistant Professor of Medicine at the University of Pennsylvania, explains the symptoms that may result in a prostate cancer diagnosis, what it means to be diagnosed with “advanced prostate cancer,” and the tests necessary for a complete diagnosis.
Transcript | Diagnosing Advanced Prostate Cancer
Dr. Narayan: My name is Vivek Narayan. I am a Chief Genitourinary, or prostate cancer medical oncologist. I see patients at the University of Pennsylvania Abramson Cancer Center, and I'm also interested in clinical trials and clinical research for prostate cancer patients as well. So specifically, for men who develop a recurrent or metastatic or more advanced prostate cancer, there's really two different ways that that can manifest. In the vast majority of patients, oftentimes it's an asymptomatic presentation of prostate cancer, at least here in the United States. Let me explain.
How Is Advanced Prostate Cancer Diagnosed?
Dr. Narayan: There's sort of one of two ways that men can ultimately be diagnosed with an advanced prostate cancer. The most common way that men are diagnosed with an advanced prostate cancer is that they already have a history of prostate cancer and would have received some form of local prostate directed treatment at some point in their past medical history. So they may have undergone surgery for prostate cancer. They may have undergone radiation therapy for prostate cancer, or they may have undergone some combination of both surgery and radiation therapy for prostate cancer. But then as part of their post-treatment monitoring, there's evidence of some recurrence and then ultimately more advanced presentation of prostate cancer. And that's usually highlighted by a rising PSA blood test value. And so oftentimes, those patients will not have symptoms of an advanced prostate cancer, but it's still identified as a new presentation of an advanced prostate cancer.
On the other hand, the minority of cases, at least here in the United States, are men who present with what we call a de novo presentation of an advanced prostate cancer. This probably makes up somewhere between five and 10% of all prostate cancer advanced presentations. But these are men who did not have any prior history of a local prostate cancer and just sort of walk in the door, so to speak, with a new finding of an advanced prostate cancer. In there, they may either have symptoms or no symptoms, and then sort of testing shows that they have an advanced prostate cancer. So, this could either be identified through a very high PSA blood test that was obtained for routine screening or it could be obtained because of some urinary symptoms or pain-related symptoms that prompted an evaluation for a diagnosis such as advanced prostate cancer.
So I think it's a great question because I think people can define "advanced prostate cancer" in different ways. And I think in large part, this is because we are fortunate in prostate cancer that we have a blood test called PSA that can help us monitor the disease. And so, there's essentially one way of thinking about it, is that there's almost sort of three phases of prostate cancer and where you draw the line between sort of advanced and non-advanced can vary. But I think it's important to understand what these three phases of the disease are.
What Are the Three Phases of Prostate Cancer?
Dr. Narayan: There's what we call sort of a clinically localized phase of the disease, which is sort of that initial presentation that I mentioned where men are oftentimes undergoing surgery or radiation therapy or some sort of locally-directed treatment, because it's presumed that the prostate cancer is confined to the prostate or the prostatic area itself.
But because we have a blood test called PSA, we are often able to identify patients who may have had a relapse of disease after such local treatment, but yet we can't identify where it may have spread throughout the body. And so whether it's somewhere in the lymph nodes or bone or somewhere still within the prostate or any of the above. Sometimes we're not able to sort of clearly delineate where that disease may be lingering, but a PSA blood test tells us that there's some concern for residual or recurrent prostate cancer. And so that would sort of capture this middle phase of the disease, oftentimes what's called biochemical recurrence or sometimes biochemical progression.
Then, sort of the third phase of the disease would be when you do have some sort of testing. So, this could be a CAT scan, MRI, various forms of PET scans or different imaging tests that can tell us where this prostate cancer may be lingering and especially if it's somewhere that has spread outside of the prostate. And that would sort of fill this third phase of the disease, what we oftentimes called metastatic prostate cancer. And so that would clearly be the sort of more advanced stage of the disease. But where a provider may sort of define "advanced prostate cancer" can vary from person to person. And also, the treatment approaches can vary depending on where that patient may fall along that whole clinical spectrum.
So, it may start with the PSA because PSA is oftentimes a good sort of early signal of what may be going on with the disease behavior. But you're exactly right, that there's oftentimes a need for further testing to better clarify what the burden or extent of the disease may be. And so conventionally, this entails imaging tests such as CAT scans or CT scans, which usually are of the chest, abdomen, and pelvis, and then some form of more sensitive bone-directed imaging, which is oftentimes a nuclear bone scan, which is specifically used for prostate cancer. So that's often, for many years now, what we've considered the conventional imaging tests to identify where prostate cancer may be, if it's occurring outside of the prostate, because those tests can evaluate the lymph nodes, they can evaluate the organs such as the liver and the lungs, and they can evaluate the skeleton. In prostate cancer, for reasons we don't fully understand, there is this proclivity for the disease to spread to the skeleton, so the ribs, the backbones, the pelvic bones. And so, a bone scan is a good way to look for that.
I would just mention that more recently, especially in the last one or two years, there's been increasing interest and now some FDA approvals for sort of more advanced types of prostate cancer imaging tests. So this falls under more the PET scan category, and there's a variety of different radio tracers that are now increasingly being used here in the United States for prostate cancer re-imaging in men who have a rising PSA. And so that would sort of fall under this more novel PET-directed image.
Why Did You Choose to Become an Oncologist?
Dr. Narayan: Sort of why that I sort of become an oncologist in the first place, but then, why prostate cancer? Why do I enjoy taking care of prostate cancer patients? I mean, I think, in many ways it's kind of a similar answer to both questions. But I like taking care of cancer patients in general, because I think it is this important balance when you have patients with cancer, of understanding obviously the anxieties and the risks of the disease itself, but also understanding that we have a wide variety of tools to treat prostate cancer, or any cancer for that matter. And those new tools are increasing day by day. And so it becomes this really, I think, nuanced balance between trying to use these effective tools and use these increasingly available tools to really treat a cancer, but also being mindful of what the actual risks of the disease may be, the anxieties that go along with both the disease and the treatment, quality of life issues and concerns. And so how individual people and providers balance these two interests is, I think, what makes oncology particularly special.
For prostate cancer patients, I think, there I was particularly attracted to that particular disease in that patient population, I think, for a couple of reasons. One is that as sort of a general perspective, I have interest in men's health and obviously prostate cancer diseases is a disease of men. It's often a disease of older men. I think it's a patient population that we need to pay attention to, and I think especially prostate cancer is one concern in that population.
Then, fortunately for prostate cancer, it has very interesting biology. It has oftentimes, thankfully, a more protracted or indolent disease course. And so it's this opportunity to really kind of think about the long-term about how to appropriately manage these patients or optimally manage these patients. Also, there are other health risks that can develop along the way. Heart disease, diabetes, other things happen in all people as we grow older, and how do we sort of think about both of those issues in the long-term for prostate cancer patients? So, I think there's a lot of nuance and a lot of, really, excitement about treating prostate cancer. Because thankfully we have a lot of great opportunities, but also a lot of considerations in how to actually use those treatments in men with prostate cancer.