Seth Blacksburg

Intensity-Modulated Radiotherapy Causes Fewer Side Effects than Three-Dimensional Conformal Radiotherapy When Used in Combination With Brachytherapy for the Treatment of Prostate Cancer

PURPOSE To measure the benefits of intensity-modulated radiotherapy (IMRT) compared with three-dimensional conformal radiotherapy (3D-CRT) when used in combination with brachytherapy for the treatment of prostate cancer. METHODS AND MATERIALS We conducted a retrospective review of all patients with localized prostate cancer who received external-beam radiotherapy (EBRT) in combination with brachytherapy with at least 1 year follow-up (n = 812). Combination therapy consisted of (103)Pd or (125)I implant, followed by a course of EBRT. From 1993 to March 2003 521 patients were treated with 3D-CRT, and from April 2003 to March 2009 291 patients were treated with IMRT. Urinary symptoms were prospectively measured with the International Prostate Symptom Score questionnaire with a single quality of life (QOL) question; rectal bleeding was assessed per the Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer Late Radiation Morbidity Scoring Schema. The Pearson χ(2) test was used to compare toxicities experienced by patients who were treated with either IMRT or 3D-CRT. Logistic regression analyses were also performed to rule out possible confounding factors. RESULTS Within the first 3 months after treatment, patients treated with 3D-CRT scored their urinary symptoms as follows: 19% mild, 44% moderate, and 37% severe; patients treated with IMRT scored their urinary symptoms as follows: 36% mild, 47% moderate, and 17% severe (p < 0.001). The 3D-CRT patients rated their QOL as follows: 35% positive, 20% neutral, and 45% negative; IMRT patients rated their QOL as follows: 51% positive, 18% neutral, and 31% negative (p < 0.001). After 1 year of follow-up there was no longer any difference in urinary morbidity between the two groups. Logistic regression confirmed the differences in International Prostate Symptom Score and QOL in the acute setting (p < 0.001 for both). Grade ≥ 2 rectal bleeding was reported by 11% of 3D-CRT patients and 7% of IMRT patients (p = 0.046); logistic regression analysis also confirmed this observation (p = 0.040). CONCLUSIONS When used in combination with brachytherapy, IMRT offers less Grade ≥ 2 rectal bleeding, less acute urinary toxicities, and is associated with a higher QOL compared with 3D-CRT.

Factors influencing urinary symptoms 10 years after permanent prostate seed implantation.

PURPOSE We investigated the factors that influenced urinary symptoms in the first 10 years after prostate brachytherapy. MATERIALS AND METHODS A total of 1,932 men were treated with prostate brachytherapy alone or with external beam irradiation and followed a mean of 6.8 years. The influence of pretreatment American Urological Association symptom score (7 or less, 8 to 19, 20 or greater), external beam radiotherapy, (125)I or (103)Pd, biological effective dose, age, prostate size and hormone therapy on the change in American Urological Association symptom score (11,491) was compared. RESULTS The mean change from initial score (7.4) was 11.4, 5.5, 3.3, 2.7, 1.5, 1.2, 1, 1, 1, 1, 1.3 and 1.4 points at 3, 6 months and 1 to 10 years, respectively (p <0.001). Factors that resulted in a greater increase in urinary symptoms at year 1 were low pretreatment score (p <0.001), no hormonal therapy (p <0.001), younger age (p = 0.046) and higher biological effective dose (p = 0.025). At 10 years patients with an initial score of 20 or greater had an average decrease of 11 points compared to a decrease of 0.9 for an initial score of 8 to 19 and an increase of 2.7 for an initial score of 7 or less (p <0.001). On linear regression the scores at 1 year were influenced by initial score (p <0.001), biological effective dose (p = 0.022), prostate size (p <0.001) and hormonal therapy (p = 0.009). At 10 years only the pretreatment score remained significant (p <0.001). CONCLUSIONS There is minimal change in mean American Urological Association symptom score (1.4 points) 10 years after prostate brachytherapy. Patients presenting with high initial scores have the greatest improvement from baseline. Biological effective dose, external beam radiotherapy, hormonal therapy, isotope, patient age and prostate size do not appear to influence long-term urinary symptoms.

Gleason 7 prostate cancer treated with low-dose-rate brachytherapy: lack of impact of primary Gleason pattern on biochemical failure.

Whats known on the subject? and What does the study add?

EFFECT OF FAMILY HISTORY ON OUTCOMES IN PATIENTS TREATED WITH DEFINITIVE BRACHYTHERAPY FOR CLINICALLY LOCALIZED PROSTATE CANCER

PURPOSE To determine the impact familial prostate cancer has on prognosis in men treated with brachytherapy for clinically localized prostate cancer. METHODS AND MATERIALS A total of 1,738 consecutive patients with prostate cancer (cT1-3, N0/X, M0) received low-dose-rate brachytherapy alone or in combination with external beam radiation therapy or hormone ablation from 1992 to 2005. The primary end-point was freedom from biochemical failure (FFBF) using the Phoenix definition. Minimum follow-up was 2 years and the median follow-up was 60 months (range, 24-197 months). RESULTS A total of 187 of 1,738 men (11%) had a family history of prostate cancer in a first-degree relative. For the low-risk patients, both groups had similar actuarial 5-year FFBF (97.2% vs. 95.5%, p = 0.516). For intermediate-risk patients, there was a trend toward improved biochemical control in men positive for family history (5-yr FFBF 100% vs. 93.6%, p = 0.076). For the high-risk patients, men with a positive family history had similar 5-year FFBF (92.8% vs. 85.2%, p = 0.124). On multivariate analysis, family history was not significant; use of hormones, high biologic effective dose, initial prostate-specific antigen value, and Gleason score were the significant variables predicting biochemical control. CONCLUSIONS This is the first study to examine the relationship of familial prostate cancer and outcomed in men treated with brachytherapy alone or in combination therapy. Men with a positive family history have clinicopathologic characteristics and biochemical outcomes similar to those with sporadic disease.

MP05-18 PROSTATE FIDUCIAL MARKER PLACEMENT IN PATIENTS WHILE ON ANTICOAGULATION: FEASIBILITY PRIOR TO PROSTATE SBRT

Objectives: Fiducial marker placement is required in patients undergoing robotic-based Stereotactic Body Radiotherapy (SBRT) for prostate cancer in order to track the six degrees of prostate motion that occur intrafractionally, during treatment. Many patients take anticoagulant medication due to other comorbidities. Anticoagulation therapy can cause patients to bleed during procedures and, in general practice, are often temporarily discontinued prior to invasive medical procedures to reduce that risk. However, some patients may not be able to temporarily discontinue anticoagulation therapy due to an increased risk of a thromboembolic event from their comorbid medical conditions. We looked at a series of our patients who were unable to discontinue anticoagulation therapy prior to fiducial marker placement and report on their outcomes to assess whether they experienced bleeding complications from the procedure. Methods: From August, 2015 to January, 2016, 16 consecutive patients on chronic anticoagulation therapy and who were not cleared to stop these medications underwent fiducial marker placement into the prostate for treatment and planning purposes. The most common indications for uninterrupted anticoagulation therapy in this cohort included: recent stent placement (6=number); myocardial infarction (6=number); pulmonary embolus (2=number); and atrial fibrillation (2=number.) Anticoagulation therapy included Aspirin (7=number); Plavix (5=number); Coumadin (3=number); Lovenox (2=number); Eliquis (1=number); Brillinta (1=number); Pradaxa (1=number); and Effient (1=number). 6 patients were on more than one of these agents at the time of fiducial marker placement. All patients had Emla cream placed on the perineum and lidocaine gel placed into the rectum prior to the procedure for numbing purposes. A transrectal ultrasound was placed for visualization of the prostate and normal anatomy as well as to provide real time image guidance of marker placement during the procedure. 2 needles with 2 fiducial markers and a spacer in each were placed transperineally into the prostate under ultrasound guidance using a brachytherapy grid. The needles were then removed after the fiducial markers were placed and gentle pressure was applied to the perineum by the nursing staff. All patients were monitored for bleeding afterwards by a registered nurse. Results: All 16 consecutive patients who were on anticoagulation and underwent fiducial marker placement were discharged home the same day of the procedure. No patient experienced significant bleeding. Conclusions: Transperineal fiducial marker placement in patients who are unable to Open Access Abstract