1. An Evaluation of Prostate Volume and Proton Therapy-Related Toxicities
Libby Krcik, BS, RT(T), Patrick Lee, MS, RT(T), CMD, Mingcheng Gao, PhD, Mark Pankuch, PhD,
Megan Boroczk, BS, William Hartsell, MD
Northwestern Medicine Chicago Proton Center

2. Purpose
To analyze trends in the occurrence rate and severity of patient reported adverse proton beam therapy toxicities as a function of prostate size for low and intermediate risk prostate cancer patients.
In other words: Does a larger prostate cause higher grade toxicities?

3. Background
The severity of symptoms from benign prostatic hyperplasia (BPH) does not correlate with the degree of hyperplasia1
The prevalence of gross hematuria in patients with BPH is unknown2-4
Other urinary tract conditions can cause similar symptoms1
We got information leaning towards the hypothesis that the size of a prostate does not really correlate to the degree of hematuria in patients who even get that symptom.
Part of the reason we wanted to find out if prostate size correlates to toxicities in patients receiving proton therapy, more specifically hematuria.
1. Edwards JL. Am Fam Physician
2. Kearny MC, Bingham JB, Bergland R, Mead-D’Alisera P, Puchner, PJ. The Journal of Urology
3. Foley SJ et al. The Journal of Urology
4. Foley SJ. The Prostate Journal

4. Methods
Prospective collection of data for 688 prostate cancer patients
Proton Collaborative Group (PCG) registry study
70.0 Gy at 2.5 Gy per fx, OR 79.2 Gy at 1.8 Gy per fx
Prostate size defined by MRI
Collected at a single institution from October 2010 to October 2016
All patients were enrolled in PCG and treated with definitive proton therapy to the intact prostate
Took out patients who received pelvic nodal irradiation
MRI found in patient’s EMR, a handful were found from ultrasound biopsy reports

5. Methods Continued < 25 76 26-50 418 51-75 155 76-100 43 > 100 22
Prostate Size (cc)
Patient Total
< 25 76
26-50
418
51-75
155
76-100 43
> 100 22
Patients divided into 5 groups
Median follow up of 2.03 years
Genitourinary, gastrointestinal, and dermatological toxicities collected
Pearson chi-square test performed
Median follow up of 2.3 years= most recent follow up minus the day of last tx ranged from 5.95 years to 0.31 years
Frequency of each toxicity grade was calculated for each prostate size group in a percentage
P-value calculated for significance of our findings

6. Gastrointestinal Results
No significant trends in gastrointestinal or dermatological toxicities
-Very very few grade 3 occurrences of any GI side effects

7. Dermatological Results
Shows no correlation based on prostate volume
-Almost all patients had grade 1 dermatitis, low instances of grade 2 but follows no pattern

8. Genitourinary Results
Notable increases in grade 1 and 2 hematuria with increasing prostate size
Very few high grade toxicities overall
Grade 1
Grade 2
Grade 3
Asymptomatic; clinical or diagnostic observations only; intervention not indicated
Symptomatic; urinary catheter or bladder irrigation indicated; limiting instrumental ADL
Gross hematuria; transfusion, IV medications or hospitalization indicated; elective endoscopic, radiologic or operative intervention indicated; limiting self care ADL
Hardly any toxicities exceeded Grade 2
CT-CAE Definitions

9. Prostate Size and Hematuria Correlation
Grade 1 p-value= .019
Grade 2 p-value= .006
Smaller prostate sizes (25-75) experienced about % grade 1 toxicity
AND 0-2.6% grade 2 toxicity
Larger prostate volume sizes (75-100cc and greater) reported grade 1 toxicities of % A fairly large increase in incidence
AND grade 2 toxicities of about 4.7%
Point out 1 occurrence of Grade 3 in range

10. Conclusion
Most proton therapy-related toxicities exhibited no significant relationship to prostate volume
Significant correlation between prostate size and incidence of low grade hematuria
Low severity of symptoms in patients treated with proton therapy irrespective of prostate size
- The low occurrence rates of all grade 3 toxicities demonstrate a…

11. Questions?