Category Archives: Prostate cancer therapy

COVID-19, ADT and Prostate Cancer


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Spoiler alert: As I start to write this, my intent is to delve into some basic science readers may find too detailed/complex and some speculation that has limited/no support and should NOT be taken as anything other than hypothesis generating. I fell in love with biology in about the 8th grade and with thinking about how to answer biology questions in medical school, so this is more self-indulgent writing rather than being written to inform.

Starting with the COVID-19 story, there have been so many excellent articles that if you haven’t read too many already, you can get a one minute overview from this video. Now for some more Screen Shot 2020-03-29 at 8.47.20 AMdetailed science. This figure from an excellent article in Science shows the real details of how the virus works and some of the drugs that might be useful in stopping or slowing it down at the cellular level. If you use your best “Where’s Waldo” approach, (and if you are an avid follower of prostate cancer biology) you may find a very familiar protein hiding in the membrane where the virus binds to the exterior of the cell, TMPRSS2. This protein is an enzyme in the family of serine proteases, proteins that can cut peptide bonds at the site of the amino acid serine. Trypsin is another example of this category of enzymes we use in the lab to release cells from petri dishes, and you use various enzymes every day in your dishwasher to digest proteins stuck to your dishes. As shown in the figure, TMPRSS2 plays a crucial role in the entry of the SARS-CoV-2 virus into the respiratory epithelial cells leading to COVID-19 disease.

I first heard of TMPRSS2 several years ago in a lecture at the PCF annual scientific meeting. Investigators at the University of Michigan found that in a large percentage of prostate cancer, the androgen response elements in DNA that control the expression of TMPRSS2 have become fused to an oncogene, ERG. Every gene in our DNA is controlled by “upstream” segments of DNA called promoters or enhancers that regulate the expression of the gene. In the case of prostate cancer the androgen receptor, AR, binds to testosterone (or DHT) and then the is translocated to the nucleus where it binds to DNA at the sites of androgen response elements, leading to transcription and expression of the “downstream” genes. A reasonable analogy is to think of testosterone flipping a light switch to “on” and the AR being the wire going to the light bulb, TMPRSS2, in our case. You are familiar with this if you know about drugs like Lupron, Zytiga, or Xtandi that block testosterone signaling in various ways. Although taking any of these drugs turns off many genes related to prostate cancer development and progression, one of these genes is clearly ERG (if you have the TMPRSS2:ERG fusion), and of course you probably turn down expression of TMPRSS2 in normal cells.

So what does this have to do with COVID-19? As you may have seen, men have approximately twice the mortality of women from infection with SARS-CoV-2. There are no doubt many possible reasons. Men smoke more. Men may not practice social distancing as much. Men have more heart disease. But what if one reason is that they express higher levels of TMPRSS2 in their respiratory epithelium? The exact mechanism of TMPRSS2 in the infection can be found in this article.  A cartoon from the article illustrates the several points in the viral infection cycle where TMPRSS2 (and other serine proteases) acts to facilitate the entry, replication and budding of the virion from a cell.

Screen Shot 2020-03-29 at 10.19.32 AM

The article discusses several drugs that are being investigated to inhibit TMPRSS2 that could hopefully be effective in fighting COVID-19. One of them, camostat (seen in the first figure in this post), is already scheduled to begin clinical trial at the end of this month.

However, there is already a very interesting global “clinical trial” underway if you have followed the above (and necessarily complex …sorry!) story about TMPRSS2. If ADT, familiar to all men with metastatic or high risk prostate cancer, turns down the expression not only of ERG and other oncogenic pathways, but also the expression of TMPRSS2, it might reduce the infection rate or morbidity/mortality from COVID-19. Looking at large global databases, it may be possible to see whether men with a diagnosis of both “prostate cancer” and “COVID-19”  can be extracted from the data, and then whether within this grouping, those men on ADT have a better outcome than those not on ADT. It would be complex, of course, since some of the men not on ADT might be on chemotherapy, or more sick in general, and thus more susceptible to dying from the infection. It might also be possible to see what the expression levels of TMPRSS2 in the pulmonary epithelium of men versus women are as a potential partial explanation of the differences in mortality. Finally, and this would be the most intriguing possibility of all, a clinical trial that combined some partially effective “drug X” from the list of drugs in the first figure with or without ADT could determine whether short term use of ADT could enhance the treatment. Proof that no one ever has a “unique” idea (and of the speed with which you can share ideas in today’s internet environment), in doing a minimal amount of literature research on this topic, I came across a preprint of a beautiful article looking at exactly the hypotheses I laid out above. It was submitted only 5 days ago! The authors have found very significant differences in the levels of expression of TMPRSS2 among adults using published databases and hypothesize that this could explain why some individuals may be more susceptible to bad outcomes. They also evaluate the potential of down regulation of the gene with ADT drugs like enzalutamide or estrogens and they conclude, “Together, these results identify existing drug compounds that can potentially be repurposed to transcriptionally inhibit TMPRSS2 expression, and suggest that the activation of estrogen pathways or inhibition of androgen pathways can be a promising modality for clinical intervention in SARS-CoV-2 infection.”

In summary, if you have prostate cancer and are on ADT, the well known side effects you put up with are unpleasant to say the least. But there is a “not-zero” possibility that your ADT is also protecting you. The best advice is still to practice social distancing, wash your hands, and be vigilant regarding your health, but maybe there is a silver lining in this story. I hope so, and there are already clinical and basic scientists exploring the hypotheses discussed above. Be well and my best wishes during these trying times!

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(Love) Advice in the time of (Cholera) Coronavirus


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I wanted the title to look like this, but the software wouldn’t let me: Love Advice in the time of Cholera Coronavirus. In any case, if you are a patient or in the patient age range of prostate cancer you are automatically at some increased risk. There isn’t much evidence that cancer patients in general who aren’t on chemotherapy or an immunosuppressive agent have much increased risk. In fact, patients on ADT may actually do a little better based on reactivation of thymic function. Here is a quote from this complex article by James Gulley and colleagues:

Analyses of these data suggest that AR expressed by thymic epithelium play an important role in thymocyte development, and could explain why androgens induce apoptosis of thymocytes in vivo but not in vitro (31). In subsequent studies, androgen withdrawal led to increased thymopoiesis and reversal of thymic atrophy in post-pubertal male mice (32) and even in aged mice (33, 34). Furthermore, thymopoiesis decreased with the administration of testosterone (35, 36). Castration also results in increased T- cell export in aged mice and increased naive splenic T cells compared to aged controls (34).

Although persistent thymic function is evident in older individuals, it is decreased, as demonstrated by lower TREC [T-cell receptor rearrangement excision circles] levels (37). However, studies show that ADT can induce thymic renewal in older individuals (38). In one study, elderly prostate cancer patients given GnRH-A experienced a notable increase in TRECs in 6 out of 10 cases, indicating renewed thymopoiesis (34). These studies suggest that the effects of androgen ablation are not limited to the young, as evidenced by restoration of thymic function and export of naïve T cells after surgical (orchiectomy) or medical (GnRH-A) castration.

 

The enhanced thymopoiesis associated with ADT has important clinical implications for the treatment of immunocompromised patients and for immunotherapy for prostate cancer (see Figure 3 for a summary of ADT’s effects on the T-cell compartment). Thymic renewal in these patients may increase the diversity of the T-cell repertoire, increasing the pool of antigens recognized by the immune system. In the setting of vaccine therapy, an increased naïve T-cell compartment may enhance the response to immunotherapy.

 A few patients have asked me about whether to postpone surgery. In general, for patients with “average” (Gleason 3+4) tumors, this would probably be OK. It is a harder decision for those with Gleason 4+3, or any component of Gleason 5. It will have to be an individual decision (as are all decisions of this sort) with your doctor. The same would apply to radiation therapy treatment which can have some immunosuppressive effects, but certainly has never been studied in this situation.

In general, I would also recommend that you put aside your political biases and listen to the scientific experts. I was disturbed by a poll presented this morning on Face the Nation that indicated a significant difference in the perceptions of risk between Republicans and Democrats. This virus does not know or care about your party or politics. Practice the social isolation being recommended by Fauci and the other experts: “We should be over-reacting to this…” It would be just fine to look back and say we did that.

If you want to delve further into the science of this (which also dispels a lot of misinformation about where the virus comes from and how it arose), you should certainly look at this presentation: http://www.croiconference.org/

And in case you haven’t been thoroughly inundated with advice or just came out from under a rock, here is the succinct list of expert recommendations:

  • Social Distancing to flatten the curve of the pandemic (reduce infectivity rate from >2 to <1):
    • Wash/sanitize hands frequently
    • If sick, do not go to work
    • Work from home if at all possible
    • Maintain your personal space when around others
    • Eliminate travel (don’t be fooled by cheap flights or hotels)
    • Reduce exposure to groups of people
    • COVID-19 can persist on hard surfaces for several days so wipe down frequent contact surfaces repeatedly
    • Recognize that social distancing will have some mental health implications so be especially compassionate

Stay home. Stay well. Here is a list of things to do:  Fun Free Time Activities_

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New findings from clinical trials 2020


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There are a number of ongoing trials or completed trials that represent attempts to develop new approaches to prostate cancer. I am sometimes asked what I know or think about them (often not as much as I would like) from various investment consultants, so I thought rather than respond to a recent list, I would just use it to explain the trials for readers of this blog. Perhaps when your friends ask you whether there is “anything new out there”, you can point them to some of these.

The PROFOUND, TALAPRO-1, TRITON-2 studies are all designed to evaluate the efficacy of small molecule drugs that inhibit “PARP” which stands for an enzyme (Poly ADP-ribose polymerase) that is involved in DNA repair. It turns out that patients who inherit a damaged/mutated version of any of several enzymes that help cells maintain their DNA integrity (BRCA1/2 being an example you may have heard of – when mutated it leads to the development of breast and ovarian cancers as well) are more likely to get prostate cancer, and often it is of the more aggressive variety. It is also a frequent condition of prostate cancer metastases in patients who no longer respond to hormone therapies (leuprolide, abiraterone, enzalutamide, etc). These patients appear to be uniquely sensitive to PARP inhibitors and several pharmaceutical companies are developing them. Olaparib and rucaparib received breakthrough designation from the FDA for accelerated development. In the PROfound trial, patients who had progressed on either enzalutamide (Xtandi) or abiraterone (Zytiga) were randomized to receive the “other” new hormonal agent or the PARP targeted drug olaparib (Lynparza). As reported by my friend/colleague Maha Hussain, the olaparib treated patients fared significantly better than the patients who received the “other hormone”. The take-home message from these trials is that we now have ways to look at the molecular underpinnings of resistant prostate cancer. If you have metastatic prostate cancer, ask your physician about the genomic tests that can be done to see if you might benefit from one of these new drugs.

In a somewhat similar design, the CARD trial evaluated treating patients who had had been treated with docetaxel (Taxotere) and then progressed while on enzalutamide or abiraterone with cabazitaxel (Jevtana) rather than the alternate hormone targeted drug. Chemotherapy with cabazitaxel was the better approach. This was similar to a previous trial called FIRSTANA that looked at alternatives of mitoxantrone or cabazitaxel in progressing docetaxel treated patients. The take-home message here is that chemotherapy with cabazitaxel may be a good choice if you don’t fit the PARP profile above, and studies have shown that cabazitaxel is preferred in terms of side effects compared to docetaxel.

Finally, I will comment on the VISION trial. PSMA stands for prostate specific membrane antigen and it is expressed on prostate cancer cells. It can be used to direct pet-scanning agents to metastatic cancer deposits and these scans are currently the most sensitive ones we have for detecting prostate cancer. These scans are available at several centers in the U.S. and are now routinely used in Europe. By linking a more radioactive isotope, Lu177 to the PSMA, you can also treat prostate cancer and early results in patients with progressive hormone refractory disease have been encouraging with more than half of patients responding. The VISION trial compares this approach with cabazitaxel to see which might be the best, but in the long run, it may be possible to use both agents, and potentially to use them even earlier before resistant disease has developed.

We have entered an era when there are numerous promising options for treatment, and the key is to get as many men  as possible to participate so we can finish the trials and get these new agents approved. We also have drugs like cabazitaxel that have been approved for some time and a better idea of when to use them. Working with a team that has the expertise to guide a patient and offer the right choices at the right time is essential for the best outcomes.

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[How to] Choose Your Own Adventure


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Back when Al Gore and I invented the internet (just kidding…but it does seem like a long time ago – before twitter, instagram, and all the rest), I had the privilege of helping my professional society create its first website, ASCO Online. As part of that effort, I wrote an introductory article to assist my colleagues in understanding what I felt lay in the future. In addition to trying to explain how browsers and the internet worked (as an amateur early adopter), I stated, “Oncologists will increasingly act as information guides rather than information resources for patients and their families with cancer.”

Herein, I will attempt to make that easier for you if you have a personal interest in prostate cancer. There are now more than 103 million “hits” in a google search for “prostate cancer”. Therefore, first understand your condition. If you are thinking about screening, put that in your search term, or read this article I selected for you.

Next, be familiar with the myriad of terms that have evolved to describe different situations (“states”, “stages”, “conditions” etc.) to describe the disease. “Localized” means you have prostate cancer that is felt to be (or even proven to be after surgery) confined to the prostate. If localized, is it high risk, intermediate risk, or low risk? Your physician should be able to help you understand this based on the Gleason score, pathology findings, and PSA, but there are now multiple molecular tests that can be done to help further characterize what has been found. There is an excellent article to help you understand these here. If you haven’t had surgery or radiation, and are just deciding what to do, some of these tests can be done on your biopsy. I once wrote a blog about the challenging decision of choosing a method of primary treatment that is still relevant here.

However to be really up to date, you may wish to look at the research going on for any of the more advanced prostate cancer conditions. For this, you should become familiar with and use the NIH website, Clinicaltrials.gov. To help you with this, I have done some preliminary searches for different conditions, but recognize that the terms you enter change what you see, so regard this as just a start. Pick your condition, and click on it and you will find some trials that are ongoing (I preselected “recruiting”) for some common situations. If you don’t see your situation, play with the search terms yourself.

High risk after surgery based on pathology
Rising PSA (biochemical failure) after surgery or radiation
Known metastatic disease (spread to bones or nodes on scans) never previously treated
Rising PSA or new metastases on scans while on hormone therapy

Now, taking the last example which gave links to 160 studies, you can narrow the search results by using the pull down menu on the search screen, starting with country. Note that limiting to the U.S. drops the available trials from 160 to 93. Adding the state, Colorado, drops it to 14 studies, etc. Maybe you have a relative in a certain city or state you could visit if a trial fits your situation. If you would like to look only at immunotherapy trials, try entering the term, “immunotherapy”.

Next, let’s go further into one trial. Let’s say we are interested in the NIH immunotherapy trial being conducted at the NCI. If you scroll down, you can see what will be involved:

Screen Shot 2019-10-05 at 12.48.14 PM

Next, since the devil is in the details, you need to know if you are eligible for this trial. Continue to scroll down to the Eligibility Criteria section. Here you find what clinical conditions you MUST have (Inclusion Criteria) or MUST NOT have (Exclusion Criteria).

At this point, you should understand how it would be almost impossible for your physician to stay up on all of the trials. YOU are now the “information guide” and if you are interested in whether a certain trial (or even an approach you have found that might be something you could do outside of a trial) could be useful in your case, you should make an appointment to speak with your doctor about the trial/approach. Recognize that this will probably take more time than your “usual visit” and notify the clinic you will want extra time to discuss this. Print out the relative parts of the trial so you can show it to her/him, and ideally have your meeting in an exam room with an internet-connected computer so you can search through details together. If there are questions, each trial has the phone number for a contact person (typically a research nurse), and since your physician may be able to answer questions you would have trouble finding in your record, this phone call is best made together from the exam room.

In our fast-moving, internet-enabled era of medicine, this is how I think medicine should be practiced. The shared burden of “keeping up” means the patient has to do his (no women have prostate cancer) or her (if you are a supportive spouse or similar) own research, help the doctor, and work on approaches as a team. Being respectful of the time involved is critical, but it CAN work. And it is much more rewarding than keeping up with tweet storms!! And if this is “not for you”, find a grandchild and choose some different adventures here. (disclaimer: I have never done this, but looks like it could be fun)

 

 

 

 

 

 

 

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ADT and Alzheimer’s Disease: risk/benefit


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The July 3 issue of JAMA Network contained a disturbing article regarding the risk of developing Alzheimer’s disease or dementia following use of androgen deprivation therapy (ADT). Using the SEER-Medicare database, the authors identified a cohort of men aged 66 or older who were diagnosed with localized or advanced prostate cancer between 1996 and 2003. The data on what happened to them in the next 10 years were then analyzed according to whether they received ADT or not in the 2 years following their diagnosis.  These were older men (74-76) who mostly lived in metropolitan areas, and 3/4 were caucasians, 2/3 were married, with just over 1/3 coming from low socioeconomic backgrounds. There were 62,330 men who received ADT, and 91,759 who did not in the final groups analyzed.

With a mean followup of 8.3 years, the risk of developing Alzheimer’s disease among the control group was 9.4% but increased to 13.1% if the men received ADT (P<0.01). Similarly, a diagnosis of dementia increased from 15.8% to 21.6% with ADT exposure, and there was evidence that the longer the men were on ADT, the worse the risk. These data are disturbing to me on two levels. First, I was unaware that 75 year old men have such a high risk for developing Alzheimer’s disease or dementia in their next decade; and second, as a frequent prescriber of ADT for men with prostate cancer in general, and particularly for those receiving curative intent radiotherapy for high risk disease, it adds to the challenge of how long to recommend such therapy (if at all). The risk curve for Alzheimer’s is shown in this figure:

Screen Shot 2019-09-04 at 2.58.07 PM

The benefit of adding ADT to curative intent radiotherapy has been demonstrated in a large number of studies dating back to the 1990’s. For example one of the most cited studies compared the survival and prostate cancer specific survival of adding 3 or 6 months of hormone therapy to radiotherapy in patients with advanced local disease. The advantage of 6 months (compared to none or 3 months) of ADT is shown in this figure, and is about 10%, somewhat better than the increased risk of developing Alzheimer’s that is probably created.

Screen Shot 2019-09-08 at 6.19.23 PM

The details of these kinds of comparisons are quite complicated – for example trying to separate out various categories of “high risk” or “higher risk” prostate cancer, etc. as reflected in this editorial by Dr. D’Amico. Numerous other studies continue to support the use of ADT to improve outcomes of radiotherapy – the challenge being how long to continue it and weighing toxicities (cardiac, quality of life, dementia risk, etc.) vs the advantage in terms of prostate cancer control. Dr. D’Amico looks forward to better information in his final statement, “During the next few years, data that will shed light on whether more than 6 months of AST is needed to prolong survival in men treated with RT for localized high risk or locally advanced prostate cancer will be provided by the completed EORTC randomized study 22961.” Stay tuned, and if you are told to take ADT to improve the outcome of radiation to your high risk localized prostate cancer, discuss the details with your physicians! How old you are, what is in your family history, and your own thoughts regarding risks of prostate cancer recurrence/death or dementia are important issues.

 

 

 

 

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Here’s your prognosis…


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Bill Farwinkle (a fictional patient) and his wife Judy are seated in two chairs in the exam room as I enter, introduce myself, and take a seat in front of the evil, glowing screen that often dominates physician/patient interactions these days. I have read through the urologist’s excellent intake notes as well as those from the radiation oncologist he saw earlier in the week. It is clear that he has been told most, if not all, of the information about his options for treating a Gleason 4+3 cancer found in 6/12 cores, plus the suspicion of a solitary metastasis in his left ilium. So, I start by asking him to tell me about his goals for today’s visit. As soon as it is convenient in the visit, I move the conversation to what he enjoyed about his import business and what he is doing with his retirement, and from there, just let them ask the questions he or Judy are most concerned about. It takes an hour more or less.

These intimate encounters are the raison d’être of my 4 decades of medical practice. Trying desperately to keep up with the molecular biology of how a loss of PTEN or the presence of a mutation in one of the many DNA damage repair genes, never mind any of the multigene panels that could be ordered, hovers over each encounter as I ponder my role in helping an individual navigate a frightening diagnosis or a change in his clinical picture. Before reading any further in this post, I hereby assign you (as is my duty, being a professor after all…) this reading assignment: “Don’t Tell Me When I’m Going to Die” (You need to click on that title and read the short article before continuing).

The promise of “precision medicine” is all the rage currently. For example, in this week’s NEJM there is an article on re-adding the clinical risk parameters to the 21-gene recurrence score now in standard use for certain breast cancer patients. In the accompanying editorial, Hunter and Longo (discussing the complexities imposed by combining clinical and genomic attributes) state, “Within these groups, both physicians and patients will have to face substantial uncertainty, and ‘educated guesses’ informed by multiple sources of evidence as well as by clinical acumen will continue to be necessary even in the age of precision medicine…”

And so, when “Mr. Farwinkle” looks me in the eye at the end of our hour and says, “I suppose you know what I’m going to ask next…” I’m fully prepared to do my best, but in my heart I realize that medicine remains an art. Does he realize that his parents’ longevity, his smoking history, his cholesterol and blood pressure, and his willingness to exercise may play as much a role as the Gleason score or any genomic tests? “How long have I got, doc?” The question hangs there as I ponder how to answer.

We all share the same prognosis: Our time is fleeting, “threescore and ten, I remember well” as Shakespeare quotes in Macbeth. How to factor in the possibility that enzalutamide or abiraterone, a PARP inhibitor, or even an immuno-oncology agent that blocks the PD-1 pathway may affect this truth by a few months or even a year or two is on the one hand hopeful, and on the other, probably irrelevant. If only I could be as eloquent as Paul Kalanithi, the author of “When Breath Becomes Air“. In his original submission to the NY Times, when he was discussing coming to grips with his own cancer diagnosis, he stated, “What patients seek is not scientific knowledge doctors hide, but existential authenticity each must find on her own. Getting too deep into statistics is like trying to quench a thirst with salty water. The angst of facing mortality has no remedy in probability.”

And so I answer the Farwinkles. “I think you are going to be fine. Regardless of your decision as to what therapy we choose, you are likely to have a good outcome initially for several years, and I will be here for you. We can get through this together and we will take great care of you. But just as I have to remind myself, every day is a gift and we should live it like there won’t be unlimited tomorrows.”

Nothing has really changed for him. Or for me. I look forward to getting to know this family better…

 

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What we see and what YOU get.


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Will Rogers is said to have stated, “When the Oakies left Oklahoma and moved to California, it raised the IQ of both states.” This story has given rise to the concept of the “Will Rogers phenomenon” in medicine that is very well explained in this essay. Basically, it provides a cautionary message when evaluating new therapies in cancer medicine, because if a new study has taken advantage of newer diagnostic techniques to eliminate some of the patients with higher risk (say those with metastases), then it could easily be that an improved result is not from the new therapy, but from the ability to throw out the higher risk patients from a study cohort.

We are certainly at risk of this now in prostate cancer. In the last 5-10 years, a number of more sensitive scans have been introduced that can reveal metastatic deposits previously missed by standard technetium-99m bone scans or CT scans. Most of these rely on the technology known as PET (positron emission tomography) scanning. The first clinical PET scans mostly utilized glucose to which a positron emitter, Fluorine-18, was attached. For bone metastases, it is easy to see how much more sensitive F-18 scans are as shown in this image: (Same patient – A. “Regular” Tc-99m bone scan  B. NaF-18 PET scan)

Screen Shot 2019-04-08 at 5.01.55 PM

Suppose you have a new treatment that is for patients “with 10 or fewer” bone metastases. If you are comparing the new treatment with one that was used in the past, and you now use the PET scan (on the right), this patient would not be eligible, whereas in the past (old scanning technique) he would have been. He clearly has a higher tumor burden than 10 metastases. Hence, he is now eliminated from the new study, and therefore the new study will automatically look better in terms of outcome than previous treatments. This is called “stage migration” or the “Will Rogers phenomenon”.

For “soft tissue” metastases (lymph nodes, liver, lung, etc.) the regular Fluorodeoxyglucose FDG-PET scans were approved decades ago for lung cancer, colon cancer, lymphomas and breast cancer but they never worked well for prostate cancer. A simplistic explanation may have to do with the different metabolism of prostate cancer which tends to utilize lipid rather than glucose for energy. (see our study here). Therefore researchers looked for other metabolites that would light up prostate cancer. Acetate and choline could be labelled with Carbon-11 and worked well. However, C-11 has a half life of only 20 minutes, so making the label in a cyclotron had to be done essentially in the room next door to the scanner and injected immediately into the patient. Another metabolite taken up by prostate cancer, an artificial amino acid (fluciclovine), could be labeled with F-18, worked well and has now been approved, called the Axumin scan.  Potentially even better will be the PSMA scan, now in research mode.

The net result of these new scans is to allow physicians to answer the frequent question patients ask, “Where is the PSA coming from?” The problem then becomes the title of this essay – What we see and what You get. There are numerous scenarios. For example, a patient who comes in with a very aggressive Gleason 9 cancer and a PSA of 12.3. Should we go immediately to a routine bone and CT scan, or just order an Axumin scan? And if we find 2 positive spots, one in a rib and the other in a lymph node, does that mean the patient can’t be cured?? Five years ago, we would have never known about the metastases and we would have operated or used radiation therapy in a curative attempt. Screen Shot 2019-04-09 at 9.56.43 PMWhat about the patient with a rising PSA 5 years after he had surgery. We do a PSMA scan and find a solitary node near the left iliac artery. Should we irradiate the node? What about operating and removing it – remember, it may not look any different from all the other nodes to the surgeon. Which one should he/she take out? And what is accomplished by these efforts? Should the PSA go down (yes if that’s the only metastasis) and what to do if it doesn’t go down. Are we playing “whack a node”? How many times do we go after spots that keep showing up, versus starting some sort of hormone therapy?

There is an excellent article addressing some of these questions written by my good friend Chris Sweeney and colleagues that you can read here. A summary quote from their article states, “Given the current limited understanding of how reliable these scans are in predicting the need for appropriate management change, data-driven guidelines and standardized consensus approaches are more critical than ever.” A review of some of the early attempts to treat a small number of metastases (called oligometastatic disease) has just appeared here. One example of a paper reporting interesting results is summarized as follows: “Of the retrospective reports, the largest includes 119 treatment‐naive patients who had ≤3 sites of oligorecurrence and received SBRT to all involved sites, with 92 of 119 (77%) undergoing pretreatment choline PET. The 3‐year distant PFS [progression free survival] rate of 31% and the 3‐year OS rate of 95% are favorable and suggest a subset of patients likely benefitted from aggressive local therapy; however, conclusions from these data are limited in the absence of a comparative control arm.”

Maybe we simply have to refer back to another quote from Will Rogers, “America is a nation that conceives many odd inventions for getting somewhere but it can think of nothing to do once it gets there.” Stay tuned…

 

 

 

 

 

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Filed under General Prostate Cancer Issues, Oligometastatic prostate cancer, Prostate cancer therapy, Targeted treatment