Brief Answer:
Radiation cystitis is a possible cause

Detailed Answer:
Hello and welcome to "Ask a Doctor" service,

I carefully read your query and understand your concern.

IMRT radiation therapy is aimed to focus the radiation beam on the cancer cells and thus causes less damage to the tissues around. Even though IMRT causes much less damage than some other forms of radiation, it still poses a risk for complications, especially for the bladder and the urethra (the tube that passes urine from the bladder out)

In your case, given the time from the IMRT radiation and your symptoms (peeing blood), the most likely diagnosis is radiation cystitis. This is an inflammation of the inner layer of the bladder which generally happens the first couple of years after radiation and causes fragile blood vessels which bleed very easy. A high pressure such as when having a bowel movement may cause these fragile vessels to bleed. Similar damages may be in the urethra as well.
In some cases, bladder cancer may happen, even though this is much rarer than radiation cystitis.

Because this episode of macroscopic hematuria (visible blood with urine) repeated twice, it may be advisable to go back to the doctor and discuss your symptoms. The doctor may do a urinalysis and decide to just do watchful monitoring and order tests in case you get more episodes or more severe bleeding.

The doctor may also choose to right away order some more tests such as:
- urinary culture to rule out infection
- urine cytology to screen for tumor
- CBC to rule out complication with anemia
- cystoscopy and kidney imaging to visualize the bladder and the kidneys and rule out lesions within them
- urodynamic tests (evaluation of the patient before-while-after peeing) are needed if a patient has difficulty urinating.

To conclude:
- radiation cystitis is a common complication with radiation therapy and is the most likely cause of the bleeding in your case. Rarely damages to the urethra or bladder tumors may be the cause.

- this could be grade 1-2 radiation cystitis, which is an early form and observational treatment is acceptable. So, the doctor may not be so worried or rush into treatments as it is most of the time, unnecessary at this stage.

- tests (as mentioned above) may be indicated to confirm the diagnosis and rule out other conditions.

I hope this answers your query. I remain at your disposal in case further medical assistance is needed.

Regards,
Dr. Antoneta Zotaj
General and Family Physician

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Brief Answer:
Detailed answer below

Detailed Answer:
Hello and welcome to "Ask a Doctor" service,

As explained above IMRT has a much lower risk for complications compared to other radiation therapies. On the other hand, toxicity with this radiation may happen as well.
Toxicity from radiation therapy is defined as acute or late toxicity. With IMRT late toxicity of the urogenital tract may happen after 6 months.
In your case, the presence of microscopic hematuria can be an indicator of grade 1 late toxicity of the urogenital tract (which is generally due to radiation cystitis).

I understand the hesitation of your doctor to consider this diagnosis with one episode of bleeding but because the episode of penile bleeding repeated and because you have microscopic hematuria some local radiation toxicity can be considered.

On the other hand, you did not mention to have any urgency, frequency or pain and difficulty with urination. This is quite reassuring and may justify just observational treatment. This is the case, especially because you do not have gross hematuria either.

As I already mentioned, the doctor may choose to wait and not do tests now and this is completely acceptable and safe (it also spares you from overtesting). Minor changes in the bladder mucosa can happen with radiation therapy and do not necessarily warrant investigations or treatment.

So, what you would be observing for is gross hematuria or symptoms with urination (frequency, urgency, difficulty, pain, etc). According to literature, minor bleeding is very common after prostate radiation and does not need treatment unless it gets gross bleeding or the above symptoms are present (grade 1 toxicity is very minor). It is generally grade 3 and higher that may need treatment.

You may need though to have CBC every few months to make sure you do not develop anemia due to microscopic hematuria.

To conclude:
- I would say it is worth waiting and seeing how your symptoms will be. I would keep a calendar and plug the information on the bleeding date and how much approximately you bled. You will need to review this with your doctor every few months. A CBC will need to be done every few months to make sure you are not developing anemia.
- meanwhile, you may also use Movicol 1-2 sachets a day to ease your bowel movement (if you need to strain), so as to reduce the risk of the bleeding while having a bowel movement.
- This is a safe approach as long as you do not have gross hematuria or other urinary symptoms. Very likely you have grade 1 toxicity which is very minor and no investigations or treatment is necessary at the moment
- if you develop gross hematuria or other urinary symptoms, you will need to see your doctor and have the examinations mentioned in my previous email.

I hope this answers your query. I remain at your disposal in case further medical assistance is needed.

Regards,
Dr. Antoneta Zotaj
General and Family Physician

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