Image guided I125 prostate brachytherapy with Hybrid Interactive Mick technique in the community setting: How does it compare?

Assessment of permanent brachytherapy combined with androgen deprivation therapy in an intermediate-risk prostate cancer group without a Gleason score of 4 + 3: a single Japanese institutional experience

OBJECTIVES

To evaluate the outcome of low-dose-rate permanent brachytherapy combined with anti-androgen deprivation therapy for intermediate-risk prostate cancer excluding biopsy Gleason score 4 + 3.

METHODS

Patients included in the intermediate-risk group were those presenting clinical stage T1c to T2c (by magnetic resonance imaging staging), Gleason score 3 + 4 or lower and/or prostate-specific antigen less than 20 ng/mL, whereas those with clinical stage T1c to T2a, Gleason score 3 + 3 and prostate-specific antigen less than 10 ng/mL represented the low-risk group, and were used as controls. In the intermediate-risk group, therapy with a luteinizing hormone-releasing hormone analog was continued for at least 6 months before and after permanent brachytherapy.

RESULTS

A total of 147 low-risk group patients and 139 intermediate-risk group patients were included in the study. The median follow up was 51 and 52 months for the intermediate-risk group and low-risk group, respectively. The 5-year overall, cause-specific and distant-metastasis-free survival rates in the low-risk group and intermediate-risk group were 97.6/99.2, 100/100 and 100/100%, respectively. The 5-year biochemical disease-free survival in these groups were 95.9 and 92.5%, respectively (P = 0.18). There was no sexual activity and desire for erection before treatment in 50%, and in 46% of the patients in the low-risk group and intermediate-risk group, respectively. Overall satisfaction score at 2 years after permanent brachytherapy significantly improved, compared with pretreatment (P = 0.0399).

CONCLUSIONS

In intermediate-risk prostate cancer, excluding biopsy Gleason score 4 + 3, permanent brachytherapy combined with androgen deprivation therapy for 6 months or more represents an effective treatment option in Japanese patients, based on a favorable prognosis, adverse event profile and quality of life analysis.

Evaluation of dosimetry and excess seeds in permanent brachytherapy using a modified hybrid method: a single-institution experience

Permanent prostate brachytherapy is frequently performed worldwide, and many studies have demonstrated its favorable outcomes. Implant seeds used in this procedure contain a precise amount of radionuclide and are completely sealed. Because these seeds are not manufactured in Japan, they are expensive (6300 yen per seed) and therefore need careful management as a radioisotope. The proper implantation technique requires considerable procedure time, good dosimetric outcomes and simple radioactive isotope management. To evaluate the modified hybrid interactive technique based on these considerations, we assessed 313 patients who underwent hybrid interactive brachytherapy without additional external beam radiotherapy. We evaluated the duration of the procedure, dosimetric factors and the total number of excess seeds. The dosimetric results from computed tomography on Day 30 of follow-up were: 172 Gy (range 130-194 Gy) for pD90, 97.8% (83.5-100%) for pV100, 54.6% (27.5-82.4%) for pV150, 164 Gy (120-220 Gy) for uD90, 194 Gy (126-245 Gy) for uD30, 210 Gy (156-290 Gy) for uD5, 0.02 ml (0-1.2 ml) for rV100 and 0 ml (0-0.2 ml) for rV150. The number of excess seeds was determined by subtracting the number of implanted seeds from the expected number of seeds calculated from previously proposed nomograms. As per our method, nine excess seeds were used for two patients, whereas using the nomograms, the number of excess seeds was approximately eight per patient. Our modified hybrid interactive technique reduced the number of excess seeds while maintaining treatment quality.

AnchorSeed for the reduction of source movement in prostate brachytherapy with the Mick applicator implant technique

PURPOSE

The purpose of this study was to evaluate the influence of potential contributing factors to the incidence of seed slippage and quality of prostate brachytherapy dosimetry comparing "coated" vs. "bare" seeds with a Mick applicator.

METHODS AND MATERIALS

Two consecutive groups of 89 patients were treated with (125)I prostate brachytherapy at a high treatment volume single institution. All the patients were evaluated with Day 0 plain films of the pelvis and CT-based dosimetry analysis. The incidence of seed slippage was quantified. The seed slippage outcome was evaluated with respect to source type (bare vs. coated). The Day 0 prostate V(100), V(150), D90%, rectal V(100), and urethra D(30) outcomes were evaluated with respect to source type.

RESULTS

A total of 13,512 seeds were placed in 178 patients. An average of 76 seeds and 16 needles were used for each patient. The bare seed group was significantly higher on fluoroscopy minutes (2.34 vs. 1.58 min), seed slippage (5 vs. 1.5 mm), volume of rectum receiving 100% of dose (0.05 vs. 0.0 cc), dose percentage received by 30% of urethra (119% vs. 113.64%), and volume of prostate receiving 100% of prescription dose (95.21% vs. 92.8%). No significant differences in volume of prostate receiving 150% of prescription dose, dose percentage received by 90% of prostate, vascular seed migration, or operating room procedure time were seen. No seed drift greater than 10mm outside the "packet" of other seeds was seen in the AnchorSeed (BrachySciences, a division of Biocompatibles, Inc. Oxford, CT) cohort.

CONCLUSION

The report is the first to show the unique "fixity" of AnchorSeed to remain in position after deployment from the Mick applicator. Minimizing seed drag can reduce dose to the penile bulb, and maximize radiation coverage to the apex of the gland.

Comparison of intraoperative ultrasound with postimplant computed tomography--dosimetric values at Day 1 and Day 30 after prostate brachytherapy

PURPOSE

To compare the results of intraoperative dosimetry with those of postimplant computed tomography (CT)-based dosimetry after (125)I prostate brachytherapy.

METHODS AND MATERIALS

We treated 412 prostate cancer patients with (125)I prostate brachytherapy, with or without external beam radiotherapy at our institution. Neoadjuvant hormone therapy was administered to 331 patients (80.3%). Implantation was performed using an intraoperative interactive technique. Postimplant dosimetry was performed on Day 1 and Day 30 using CT imaging. The dosimetric results for the prostate, urethra, and rectum were compared among intraoperative ultrasound, and CT scans of Day 1 and Day 30.

RESULTS

The mean intraoperative minimal dose received by 90% of the prostate volume (D(90)) was 118.8% of the prescribed dose vs. 106.4% for Day 1 (p < 0.01) and 119.2% for Day 30 (p = 0.25). There were no significant correlations between the intraoperative D(90) and the postimplant D(90) values (intraclass correlation coefficients=0.42 and 0.33 for Day 1 and Day 30, respectively). Prostatic edema at Day 1 had the largest effect on the Day 1 D(90) (p < 0.01). The factor significantly affecting the Day 30 D(90) was neoadjuvant hormone therapy (p < 0.01). The mean Day 30 D(90) for the hormone-treated patients was 117.9%, compared with 124.6% for those who remained hormone naïve. The intraoperative and postimplant dosimetric values differed significantly for the urethra and rectum.

CONCLUSIONS

Our results demonstrate that there are no significant differences between the D(90) assessments obtained intraoperatively and at Day 30 postoperatively. Furthermore, there are no definite correlations between intra- and postimplantation dosimetric values. Other D(90) values differed significantly between the intraoperative and postimplant dosimetry. This study suggests that dosimetry has negligible clinical utility for informing patients, at discharge, of whether or not their implants are adequate.

Modern brachytherapy for treatment of prostate cancer

BACKGROUND

Prostate cancer is the most common cancer diagnosed in men. An increasing number of these patients are seeking minimally invasive procedures such as transperineal interstitial permanent radioactive seed prostate brachytherapy.

METHODS

This paper reviews the historical perspective and the current advances in transperineal interstitial permanent radioactive seed prostate brachytherapy. The 10- to 15-year results data now published for brachytherapy alone or in combination with external-beam irradiation are also reviewed.

RESULTS

Modern brachytherapy using transperineal interstitial permanent radioactive seed prostate brachytherapy offers patients an excellent quality of life with convenient outpatient treatment with long-term (10- to 15-year) biochemical relapse-free survival rates ranging from 67% to 87%, depending on risk stratification.

CONCLUSIONS

Modern-day brachytherapy utilizing either radioactive iodine-125 or palladium-103 alone or in combination with supplemental external-beam treatment offers patients a successful treatment outcome with acceptable toxicity.

Acute urinary morbidity following I-125 prostate brachytherapy

BACKGROUND

In Japan, iodine-125 (I-125) prostate brachytherapy has been legally approved since July 2003, and this method is becoming more popular. The purpose of the present study was to assess acute urinary morbidity within the first 6 months after I-125 prostate brachytherapy.

METHODS

A group of 130 consecutive patients with localized prostate cancer was treated with I-125 prostate brachytherapy between September 2003 and June 2004,either alone (monotherapy; 66 patients) or in combination with external-beam radiotherapy (combined therapy; 64 patients). Urinary morbidity was evaluated using the National Cancer Institute - Common Terminology Criteria for Adverse Events, version 3.0.

RESULTS

During the follow-up, 111 patients (85.4%) developed some degree of urinary symptoms such as frequency, retention, dysuria, incontinence, or hematuria. Urinary frequency (73.1%) and retention (66.9%) were the most common, and showed no significant differences between the monotherapy group and combined therapy group (P = 0.352 and P = 0.630, respectively). Six patients (4.6%) required catheterization for urinary obstruction; the median time to onset was 1.5 days (range, 1-192 days). Five of these 6 patients received monotherapy and the other received combined therapy.

CONCLUSION

Manifestations of acute urinary morbidity, especially frequency and retention, are relatively common but acceptable events after I-125 prostate brachytherapy.