Radiation proctitis after iodine-125 low-dose-rate prostate brachytherapy utilizing SpaceOAR hydrogel.

OBJECTIVE: We retrospectively evaluated the efficacy of combining the SpaceOAR (SOAR) hydrogel with prostate brachytherapy, using colonoscopy findings to assess for radiation proctitis. METHODS: Among 731 patients undergoing iodine-125 low-dose-rate prostate brachytherapy (LDR-BT), SOAR was utilized in 394 patients (53.9%). Colonoscopy was performed for 97 patients (13.3%) to assess the presence, location, condition, and treatment of radiation proctitis. We also investigated treatment factors associated with the occurrence of radiation proctitis. RESULTS: Radiation proctitis was observed in 57 patients (7.8%) and 17 (2.3%) were treated with argon plasma coagulation (APC). The incidence of radiation proctitis was 12.2% in the non-SOAR and 4.1% in the SOAR group (p < 0.001). In the non-SOAR group, the incidence of radiation proctitis was 6.6% for LDR-BT monotherapy and increased to 22.0% when combined with external beam radiation therapy (EBRT) (p = 0.001). However, in the SOAR group, these rates significantly decreased to 3.3% and 5.7% for monotherapy and combination therapy, respectively (p = 0.035, p < 0.001). With SOAR, inflammation was observed directly above the DL in most patients (87.5%), and only one patient (6.3%) required APC. The absence of SOAR (p < 0.001, HR = 0.29) and the concurrent use of EBRT (p = 0.018, HR = 2.87) were identified as significant risk factors for the occurrence of radiation proctitis. CONCLUSION: The use of SOAR significantly reduced the incidence of radiation proctitis in patients undergoing LDR-BT monotherapy and combined EBRT. Inflammation primarily occurred directly above the DL; further examination is necessary to clarify its cause.

Placement of SpaceOAR hydrogel spacer for prostate cancer patients treated with iodine-125 low-dose-rate brachytherapy.

OBJECTIVES: The aim of the present study was to report on our early experience with hydrogel spacer (SpaceOAR) placement in combination with iodine-125 low-dose-rate brachytherapy for prostate cancer. METHODS: From April 2018, SpaceOAR hydrogel spacer was placed in 100 consecutive patients undergoing iodine-125 low-dose-rate brachytherapy. Complications and the status of the placement were evaluated. Deformation of the prostate by the spacer was examined measuring prostate diameters and evaluating the change from preoperative status. The position of the prostate was similarly examined by evaluating the change in distance between the pubic symphysis and the prostate. Post-plan dosimetric data were compared with 200 patients treated without a spacer. RESULTS: No complications were found during either the intraoperative or perioperative periods. The mean displacement distance of 11.64 mm was created, the mean value before spacer placement was 0.28 mm (P < 0.0001). The change of the prostate diameters showed a positive increase in all directions, with no significant negative change in any one direction. Regarding the change in distance between pubic symphysis and the prostate, no significant shortening trend was observed between the two groups (P = 0.14). Whereas the dosimetric parameters showed means of 0.001 and 0.026 cc for RV150 and RV100 in the spacer group, they were 0.025 and 0.318 cc, respectively, in the non-spacer group, showing a significant decrease in both parameters (P < 0.001). CONCLUSIONS: Prostate deformation secondary to hydrogel placement might adversely affect dosimetric parameters in patients undergoing low-dose-rate brachytherapy. However, a significant reduction in the rectal dose can be adopted without adversely affecting the other parameters related to treatment outcome.

Transperineal interstitial permanent prostate brachytherapy for Japanese prostate cancer patients in Hawaii.

BACKGROUND: Our aim was to report clinical and biochemical outcomes of transperineal interstitial permanent prostate brachytherapy in the treatment of Japanese patients with clinically organ-confined prostate cancer in Hawaii. METHODS: Ninety-five Japanese patients underwent transperineal interstitial permanent prostate brachytherapy using either iodine-125 or palladium-103 for clinical T1c-T2b N0 M0 prostate cancer. These procedures were carried out between December 1998 and December 2002 at The Queen's Medical Center in Honolulu, Hawaii. Prostate-specific antigen measurements were collected from all patients at follow up. Biochemical failure was defined by three consecutive rises in prostate-specific antigen levels, based on the criteria of the American Society for Therapeutic Radiology and Oncology Consensus panel. RESULTS: The median patient age was 71 years (range, 46-87 years). Thirty-six patients were implanted with either iodine-125 or palladium-103 as monotherapy; 59 patients received moderate-dose external beam irradiation first, followed by a prostate brachytherapy boost. The median follow-up length, calculated from the day of implantation, was 801 days (range, 237-1421 days). During this follow-up period, The Kaplan-Meier estimate of freedom from biochemical failure in this series was 94%. No major complications were observed. CONCLUSIONS: Clinical and biochemical outcomes in the treatment of Japanese patients in Hawaii suffering from localized prostate cancer, using transperineal interstitial permanent prostate brachytherapy, with or without external beam irradiation, compared favorably to results in similarly treated patients in the general US population.

[PSA bounce phenomenon after transperineal interstitial permanent prostate brachytherapy for localized prostate cancer].

PURPOSE: We described the temporarily increase phenomenon in prostate-specific antigen level (PSA bounce) after transperineal interstitial permanent prostate brachytherapy (TIPPB) for localized prostate cancer. MATERIALS AND METHODS: From December 1998 to May 2003, 500 consecutive patients with localized prostate cancer were treated with TIPPB using iodine-125 or palladium-103. We examined 200 patients who have more than 2-year PSA follow-up. Median follow-up length was 1,069 days (range, 712-1,411 days). No patient received neoadjuvant or adjuvant hormone therapy. PSA determinations were performed every 3 months for the first 2 years after procedure, and every 6 months hereafter. PSA bounce was defined as an increase of 0.1 ng/ml or greater above the preceding PSA level after implant followed by a subsequent decrease below that level. The American Society for Therapeutic Radiology and Oncology (ASTRO) consensus panel criteria 1996 were used to define biochemical failure. RESULTS: PSA bounce was observed in 40% (80/200) of the cases receiving TIPPB. The median time to PSA bounce was 13 months from the day of implant. The median magnitude of the PSA bounce was 0.3 ng/ml from the pre-bounce level. Twelve cases demonstrated biochemical failure according to the ASTRO consensus guidelines of three consecutive rises in PSA. Ten of these subsequently showed a drop in PSA, consistent with biologic control of their disease. Two cases remain classified as apparent biochemical failures. CONCLUSIONS: A transient rise in the PSA following TIPPB, the so-called "bounce" is a common occurrence. The apparent PSA control of ten of twelve cases failing by the ASTRO criteria raises some concern. Further observation will be necessary to determine ways to discriminate these from true disease progression.