Got stones? What to do with them in the kidney but they aren’t blocking- a very common question.

Your Best Management for Asymptomatic Nonobstructing Kidney Stones

Urology – August 30, 2015 – Vol. 33 – No. 2

Lower-pole kidney stones are less likely to become symptomatic during observation.

Article Reviewed: The Natural History of Nonobstructing Asymptomatic Renal Stones Managed With Active Surveillance. Dropkin BM, Moses RA, et al: J Urol; 2015;193 (April): 1265-1269.

Objective: To determine the natural history of observed nonobstructing asymptomatic kidney stones and factors associated with eventual stone-related events.

Design: Retrospective chart review of the records of 160 kidney stones in 110 patients on active surveillance.

Methods: Stone characteristics, patient characteristics, and stone-related parameters were evaluated to determine factors for stone-related symptoms, spontaneous passage, requirement for surgical intervention, and stone growth.

Results: 160 stones with an average size of 7.0 mm ± 4.2 mm in 110 patients were followed up 41 ± 19 months. A total of 28% (45 of 160) of stones caused symptoms and 2% (3 of 160) caused silent obstruction on average of 37 ± 17 months. Upper-pole/mid-pole stones were more likely than lower-pole stones to become symptomatic (40%) or pass spontaneously (15%). No other factors demonstrated statistical significance in predicting symptoms.

Conclusions: Over a 3-year period, most asymptomatic nonobstructing renal calculi remained asymptomatic. Approximately 30% caused symptoms, 20% required surgical intervention, 20% grew >50% initial size, and 7% passed spontaneously. Lower-pole stones caused fewer issues than upper- or mid-pole stones. Silent obstruction may occur and necessitates regular imaging and follow-up of even asymptomatic stones.

Reviewer’s Comments: This is a very nice article following the natural history of asymptomatic nonobstructing kidney stones, which are often picked up on imaging for other indications. It shows almost identical results to previous studies, which is that over a specified period (average of 3 years in this study), approximately 30% of stones will become symptomatic or need intervention. In this study, however, if you account for patients (instead of stones), nearly 40% became symptomatic over the study period. One must also consider that 20% of stones in this study grew >50% their original size. A small percentage developed silent obstruction, which is the most concerning aspect in regard to possible renal function loss. The authors conclude that most stones remain asymptomatic over time and hint that active surveillance may be the best option. The authors make a very valid point. However, the debate becomes whether you and your patient consider 30% to 40% as an acceptable number. Are we really saving 70% of individuals from needed intervention or having symptoms, or are we just delaying the inevitable? With the exception of uric acid stones, which may dissolve, stones do not disappear. I think with longer follow-up, more will eventually become symptomatic.

Whether you treat prophylactically or only treat when indications arise becomes a decision between you and your patient. It also is influenced by the patient’s age, health, anxiety, history of kidney stones, and lifestyle. Overall, this is a nice article to provide numbers to patients in regard to nonobstructing asymptomatic kidney stones.

(Reviewer–David A. Duchene, MD).


Author: Dropkin BM, Moses RA, et al
Author Email:

Happy Valentines Day…From Mr. Prostate?

Dr. Fabrizio Dal Moro is an assistant professor of urology  in Padova, Italy. He is a connection of mine on Linkedin. He creates interesting anatomic drawings that pertain to the particular surgery  he may doing that day. Below is today’s submission by him. You can visit his website and see other drawings by him. Happy Valentines day from your little friend…the prostate!


Two negative prostate biopsies, taking Proscar and Psa 13. What to do?


This is a real scenario and shows the complexity of managing certain situations about the prostate. Part of the problem is the common misconceptions about the prostate and prostate  cancer. As well all the things you read in the paper or hear on TV about new studies showing that the PSA is unreliable and is used too often by Urologists and in turn resulting in too many men being biopsied and then subsequently being treated…and subsequently as a result negatively affecting their lives with incontinence and impotence.

So imagine you are in the exam room with your doctor in the above situation and your urologist is walking you through the fine line of doing just the right amount of tests or procedures to determine if you have prostate cancer. The bottom line is that if you have cancer and this is found out a year after your office visit…you’d be quite disappointed and probably mad…probable the word “lawyer” may come to mind.

As Bart Simpson said when asked his thoughts on “why does increasing military might and expenditures on weaponry actually act a deterrent to war?”

Bart had wrongly been put in a genius class because the test scores of a brilliant student had been attributed to him. He said, “Well.. I guess you’re damned if you do and damned if you don’t!”


So…in the conundrum I’ve described in the title of this post…the issues-

  • The two negative biopsies performed five years ago were negative however that was five years ago and things change. Just because a patient says, “But I have had a biopsy before and it was okay. Isn’t that enough?” Well a lot can happen or change in five years. Yes you didn’t have it then but that was then and this is now.
  • There is the issue of prostate cancer being in unusual places in the prostate that is not a easily sampled on a biopsy. If you look at a picture of a prostate the part that is examined by the urologist  on a rectal exam is the posterior lobe of the prostate. This does not examine the inner or anterior aspect of the prostate. The exam is a good exam and necessary but does not evaluate the “entire gland.”
  • Now you throw in the drug Proscar or generic name Finasteride. Five years ago the biopsies were negative and the PSA then was 15. Now the PSA is 13. The patient concludes that- I have had two negative biopsies and now my PSA is less than five years ago. Well Proscar lowers the PSA by about 50%. So off the Proscar this patient’s PSA could well be 20.
  • The patient stops going to the Urologist because his family doctor is doing the PSA now and it is less than five years ago but the family doctor and the patient are looking at a PSA that hasn’t changed appreciably and “stay the course.”
  • The PSA being the same or lower is not better. The Proscar is “masking” the true value.
  • So the feeling is that all is well with this patient. Well to the urologist who sees this patient…he is concerned. He also has to explain the above and put out there that some other sort of evaluation must be done to be sure the Proscar isn’t deceiving everyone.
  • If the patient for whatever reason  goes back to the urologist, the urologist will note the scenario above and recommend doing something to update the situation and hopefully show that there is indeed no prostate cancer. Again sitting on this situation and the patient is found to have an aggressive form of prostate cancer because it has been allowed to smolder undetected because of the masking effect of the Proscar…well that is a problem for all. I would think the urologist would found potentially at fault.
  • Again remember in the back drop…all the misconceptions that prostate cancer is the slow growing type and that people don’t die of it. And of course the old standby by the male not wanting a rectal exam or another biopsy, “I don’t have any symptoms.”
  • The channel that the male voids through is well away from the posterior aspect of the prostate and so for there to urinary symptoms the cancer would have to be extensive to cause voiding symptoms. In other words when found it is too late.

How about this added to the above scenario? The patient has seen the urologist and has had the two negative biopsies and his PSA is stable on the Proscar (which actually is should be half). The family doctor gets the PSA, and it is unchanged. The family doctor says to the patient, “I’ll leave your prostate exam to your urologist.” The patient however has not seen his urologist for five years. Uh oh! Do you see the perfect storm brewing…yes quite the opportunity for the late diagnosis of prostate cancer due to numerous factors and misconceptions on several layers. Of note in the above situation…the urologist is out of the loop. The patient has stopped going to him and being “checked up” by the family guy.

This is like in baseball the center fielder and the right fielder are both approaching a fly ball. The center fielder yells as they both close in on the ball, one in which it looks like both could catch but both struggling to get there. The center fielder says, “I got it.” The right fielder backs off, the center fielder realizes that he will not be able to get to the ball and then yells, “You take it.” The ball falls safely between the two fielders. Just as too many chefs spoil the soup so too it can be said of doctors “I got it, you take it” type arrangement in which things fall through the proverbial cracks of patient care.

So one day on the blood work of the family doctor the PSA does go up. “Hmmmm, your PSA is going up. Have you been seeing your urologist? You haven’t? Well it may time to go back to him and let him evaluate these numbers.” The doctor then remembers that the patient is on the Proscar. He becomes concerned.

The family doctor remembers the warnings that pop up on his medical record screen regarding patient’s taking Proscar: Proscar does not cause prostate cancer if prostate cancer is found in a patient taking Proscar it is further along and more aggressive, i.e. the “masking effect” in lowering the PSA delays the diagnosis.

The patient is now back with his urologist after five years and the options are discussed.

  • Of course now a rectal exam is done after five years of not checking it.
  • You could do another biopsy
  • You could do a prostate MRI
  • You could do various PSAs that predict the chances of a positive biopsy

If another biopsy is done it may be negative but it may not. And this is not a situation  the patient, the family doctor or the urologist wants to be in.

Summary-Negative biopsies, being on Proscar, reluctant male patients  not wanting to be messed with, misconceptions about prostate cancer, misunderstandings of the family doctor thinking the urologist is more involved in the care of a patient than the urologist actually is-all create a perfect storm of the late diagnosis of prostate cancer.

As my mother would say, “A word to the wise is sufficient”