Efficacy of a hydrogel spacer for improving quality of life in patients with prostate cancer undergoing low-dose-rate brachytherapy alone or in combination with intensity-modulated radiotherapy: An observational study using propensity score matching

BACKGROUND

It is unclear whether a hydrogel spacer can improve quality of life (QOL) in patients undergoing low-dose-rate brachytherapy (LDR-BT) alone or in combination with intensity-modulated radiotherapy (IMRT).

METHODS

We enrolled patients with prostate cancer who underwent LDR-BT alone with (n = 186) or without (n = 348) a hydrogel spacer, or underwent LDR-BT in combination with IMRT with (n = 70) or without (n = 217) a hydrogel spacer. QOL was evaluated using Expanded Prostate Cancer Index Composite (EPIC) questionnaires at baseline and 1, 3, 6, 12, and 24 months after implantation. The groups were compared using propensity score matching analysis.

RESULTS

Among patients who underwent LDR-BT alone, there were no differences regarding changes in urinary, bowel, sexual, or hormonal domain scores between the spacer and no-spacer groups; however, the dose at the bowel was significantly lower in the spacer group than in the no-spacer group. Among patients who underwent LDR-BT in combination with IMRT, there were no differences regarding changes in urinary, sexual, or hormonal domain scores between the spacer and no-spacer groups. However, the changes in the bowel domain score were significantly lower in the spacer group than in the no-spacer group (p < 0.001).

CONCLUSIONS

A hydrogel spacer may not improve impaired urinary, bowel, or sexual QOL in patients undergoing LDR-BT alone. However, in patients undergoing LDR-BT in combination with IMRT, a hydrogel spacer can improve impaired bowel QOL but not sexual or urinary QOL.

Effectiveness of intraoral stents in reducing oral adverse events during radiotherapy for maxillary or nasal cavity malignant tumors

PURPOSE

Many patients experience oral adverse events during head and neck cancer radiotherapy (RT). The methods of management of such events are under debate. One such technique is the intraoral stent (IOS) technique, which removes normal tissue from the irradiation field. This retrospective study examined the factors associated with the occurrence of oral mucositis (OM) and dysgeusia and the efficacy of IOSs in preventing them.

METHODS

Twenty-nine patients who underwent RT in the maxilla or nasal cavity between 2016 and 2022 were included. They were investigated for background characteristics, treatment factors (IOS and dose-volume histogram), and oral adverse events (OM and dysgeusia).

RESULTS

Significant risk factors for the incidence of grade ≥ 2 (Common Terminology Criteria for Adverse Events v5.0) OM were the non-use of IOSs (p = 0.004) and diabetes (p = 0.025). A significant risk factor for the incidence of grade ≥ 1 dysgeusia was concomitant chemotherapy (p = 0.019). The radiation dose to the tongue was significantly lower in the IOS group than in the non-IOS group.

CONCLUSION

Our findings suggest that the use of an IOS during RT reduces the severity of OM by reducing irradiation to the tongue. Therefore, the use of an IOS is recommended during RT performed in the maxilla or nasal cavity.

Factors associated with quality of life in patients receiving palliative radiotherapy for bone metastases: a secondary cross-sectional analysis of data from a prospective multicenter observational study

OBJECTIVE

To identify factors significantly associated with quality of life (QOL) and determine if these associations are strong enough to predict certain aspects of QOL without measuring them.

METHODS

We conducted an exploratory secondary analysis of baseline data of 224 patients (enrolled between December 2020 and March 2021) from a previously published prospective observational study on radiotherapy for bone metastases at 26 centres. Using univariable linear regression, we assessed the association between patient/treatment factors and QOL scale scores as measured by the European Organization for Research and Treatment of Cancer (EORTC) QOL Questionnaire Core 15-Palliative (QLQ-C15-PAL) and the EORTC QOL Questionnaire Bone Metastases module (QLQ-BM22).

RESULTS

Age and sex were not significantly associated with QOL. Worse performance status, higher pain scores, and opioid and single-fraction use were significantly associated with most QOL scales; these four factors were associated with worse global QOL, worse functioning status, and more severe symptoms. The coefficients of determination for most QOL scales were less than 0.2, indicating that most of the variability in QOL scores was not explained by any of the explanatory variables.

CONCLUSION

Performance status, pain intensity, and opioid and single-fraction use were significantly associated with most QOL scales. However, the associations were not strong enough to estimate QOL.

ADVANCES IN KNOWLEDGE

To date, the association between treatment factors and QOL in patients with bone metastases has not been fully studied. We identified the factors that were significantly associated with QOL and found that these associations were not strong enough to predict QOL.

Quality of life in patients who underwent robot-assisted radical prostatectomy compared with those who underwent low-dose-rate brachytherapy

BACKGROUND

To compare the quality of life (QOL) in patients who underwent robot-assisted radical prostatectomy (RARP) or low-dose-rate brachytherapy (LDR-BT) for prostate cancer.

METHODS

We enrolled patients who underwent LDR-BT (LDR-BT alone [n = 540] or LDR-BT plus external beam radiation therapy [n = 428]) and RARP (n = 142). QOL was evaluated using the International Prostate Symptom Score, Expanded Prostate Cancer Index Composite (EPIC), Sexual Health Inventory for Men (SHIM), and 8-item Short Form (SF-8) health survey. The two groups were compared using propensity score matching analysis.

RESULTS

At 24 months after treatment, the number of patients with worsened urinary QOL in the urinary domain of EPIC compared with baseline was 78/111 (70%) and 63/137 (46%) in the RARP and LDR-BT groups, respectively (p < 0.001). In the urinary incontinence and function domain, this number was higher in the RARP group versus the LDR-BT group. However, in the urinary irritative/obstructive domain, the number of patients with improved urinary QOL at 24 months compared with baseline was 18/111 (16%) and 9/137 (7%), respectively (p = 0.01). Regarding the SHIM score, sexual domain of EPIC, and mental component summary of SF-8, there were more number of patients with worsened QOL in the RARP group than in the LDR-BT group. In the EPIC bowel domain, the number of patients with worsened QOL was lower in the RARP group versus the LDR-BT group.

CONCLUSION

The differences in QOL observed between patients treated with RARP and LDR-BT could assist in treatment selection for prostate cancer.

Income and Employment of Patients at the Start and in the Follow-up of Palliative Radiotherapy for Bone Metastasis

Purpose

The aim of this study was to understand the income and employment status of patients at the start of and during follow-up after palliative radiation therapy for bone metastasis.

Methods and Materials

From December 2020 to March 2021, a prospective multi-institutional observational study was conducted to investigate income and employment of patients at the start of administration of radiation therapy for bone metastasis and at 2 and 6 months after treatment. Of 333 patients referred to radiation therapy for bone metastasis, 101 were not registered, mainly because of their poor general condition, and another 8 were excluded from the follow-up analysis owing to ineligibility.

Results

In 224 patients analyzed, 108 had retired for reasons unrelated to cancer, 43 had retired for reasons related to cancer, 31 were taking leave, and 2 had lost their jobs at the time of registration. The number of patients who were in the working group was 40 (30 with no change in income and 10 with decreased income) at registration, 35 at 2 months, and 24 at 6 months. Younger patients (P = 0), patients with better performance status (P = 0), patients who were ambulatory (P = .008), and patients with lower scores on a numerical rating scale of pain (P = 0) were significantly more likely to be in the working group at registration. There were 9 patients who experienced improvements in their working status or income at least once in the follow-up after radiation therapy.

Conclusions

The majority of patients with bone metastasis were not working at the start of or after radiation therapy, but the number of patients who were working was not negligible. Radiation oncologists should be aware of the working status of patients and provide appropriate support for each patient. The benefit of radiation therapy to support patients continuing their work and returning to work should be investigated further in prospective studies.

Local dose (biologically effective dose ≥180 Gy2) is an important predictor of biochemical recurrence in patients undergoing low-dose-rate brachytherapy

OBJECTIVES

To evaluate prognostic factors of biochemical recurrence (BCR) in each risk group of prostate cancer patients who underwent low-dose-rate brachytherapy (LDR-BT).

METHODS

A total of 944 patients with clinically confirmed prostate cancer (cT1c-3aN0M0) who had underwent LDR-BT were enrolled. The low-, intermediate-, and high-risk groups included 278, 498, and 168 patients, respectively. The median age, PSA value at diagnosis, and the follow-up period were 70 years (range: 48-84), 7.2 ng/ml (range: 1.2-113), and 91 months (range: 2-192), respectively. We evaluated the BCR-free rate, BCR-free survival, clinical recurrence-free rate, overall survival (OS), and cancer-specific survival (CSS). We conducted multivariate analysis to elucidate prognostic factors of BCR for all patients and for each risk group.

RESULTS

The 5- and 10-year OS rates were 96.0% and 89.5% and the 5- and 10-year CSS rates were 99.8% and 99.1%, respectively, while the 5- and 10-year BCR-free rates were 96.6% and 92.5% in low-risk patients, 95.7% and 90.7% in intermediate-risk patients and 93.8% and 89.0% in high-risk patients, respectively. There were no significant differences between the risk groups. Age-adjusted multivariate analysis indicated biologically effective dose (BED) <180 Gy2 as an independent prognostic factor of BCR in all patients (p = 0.005). There were no independent factors in the low- and high-risk groups, but neoadjuvant androgen deprivation therapy (ADT) (p = 0.022) and BED <180Gy2 (p = 0.042) were independent prognostic factors in the intermediate-risk group.

CONCLUSIONS

LDR-BT can achieve a higher recurrence-free survival with an adequate local radiation dose (BED ≥ 180 Gy2).

Comparative effectiveness of low-dose-rate brachytherapy with or without external beam radiotherapy in favorable and unfavorable intermediate-risk prostate cancer

We compared clinical outcomes associated with seed brachytherapy (SEED-BT) alone and SEED-BT plus external-beam radiotherapy (EBRT) for intermediate-risk prostate cancer using propensity score-matched analysis. From 2006 to 2011, 993 patients diagnosed with intermediate-risk were treated with either SEED-BT alone (n = 775) or SEED-BT plus EBRT (n = 158) at 3 tertiary hospitals. In the propensity score-matched analysis (102 pairs), median follow-up was 95 months (range 18–153 months). The 8-year biochemical recurrence-free rate (bRFR) was significantly better with SEED-BT alone than with combined radiotherapy (93.3% vs. 88.4%; HR 0.396; 95% CI 0.158–0.991). Grade 2 or greater late genitourinary toxicities were significantly fewer with SEED-BT alone than with combined radiotherapy (21.0% vs. 33.2%; HR 0.521; 95% CI 0.308–0.881). Similarly, grade 2 or greater late gastrointestinal toxicities were significantly fewer with SEED-BT alone (0% vs. 12.2%; HR 0.125; 95% CI 0.040–0.390). For the unfavorable intermediate-risk subgroups, SEED-BT alone yielded a significantly better bRFR than the combined radiotherapy (HR 0.325; 95% CI 0.115–0.915). SEED-BT alone might be a better disease-management plan than SEED-BT plus EBRT for intermediate-risk prostate cancer regardless of favorable and unfavorable characteristics.

Direct comparison of low-dose-rate brachytherapy versus radical prostatectomy using the surgical definition of biochemical recurrence for patients with intermediate-risk prostate cancer

Background

We compared the oncological outcomes of patients who received seed brachytherapy (SEED-BT) with those who received radical prostatectomy (RP) for intermediate-risk prostate cancer.

Methods

Candidates were patients treated with either SEED-BT (n = 933) or RP (n = 334). One-to-one propensity score matching was performed to adjust the patients’ backgrounds. We compared the biochemical recurrence (BCR)-free rate using the Phoenix definition (prostate-specific antigen [PSA] nadir plus 2 ng/mL) for SEED-BT and the surgical definition (PSA cut-off value of 0.2 ng/mL) for RP. We also directly compared the BCR-free rates using the same PSA cut-off value of 0.2 ng/mL for both SEED-BT and RP.

Results

In the propensity score-matched analysis with 214 pairs, the median follow-up treatment was 96 months (range 1–158 months). Fifty-three patients (24.7%) were treated with combined SEED-BT and external-beam radiotherapy. Forty-three patients (20.0%) received salvage radiotherapy after RP. Comparing the BCR-free rate using the above definitions for SEED-BT and RP showed that SEED-BT yielded a significantly better 8-year BCR-free rate than did RP (87.4% vs. 74.3%, hazard ratio [HR] 0.420, 95% confidence interval [CI] 0.273–0.647). Comparing the 8-year BCR-free rate using the surgical definition for both treatments showed no significant difference between the two treatments (76.7% vs. 74.3%, HR 0.913, 95% CI 0.621–1.341). SEED-BT had a significantly better 8-year salvage hormonal therapy-free rate than did RP (92.0% vs. 85.6%, HR 0.528, 95% CI 0.296–0.942, P = 0.030). The 8-year metastasis-free survival rates (98.5% vs. 99.0%, HR 1.382, 95% CI 0.313–6.083, P = 0.668) and overall survival rates (91.9% vs. 94.6%, HR 1.353, 95% CI 0.690–2.650) did not significantly differ between the treatments.

Conclusions

The BCR-free rates did not significantly differ between patients treated with SEED-BT and those treated with RP for intermediate-risk prostate cancer even when they were directly compared using the surgical definition for BCR. SEED-BT and RP can be adequately compared for oncological outcomes.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13014-022-02046-x.

Impact of neoadjuvant androgen deprivation therapy on postimplant prostate D90 and prostate volume after low-dose-rate brachytherapy for localized prostate cancer

OBJECTIVE

Higher quality of postimplant dosimetric evaluation is associated with higher biochemical recurrence-free survival rates after low-dose-rate brachytherapy for localized prostate cancer. Postimplant prostate D90 is a key dosimetric parameter showing the quality of low-dose-rate brachytherapy. In this study, to improve the quality of low-dose-rate brachytherapy for localized prostate cancer, we investigated pre-implant factors affecting the reduction of postimplant prostate D90.

METHODS

A total of 441 patients underwent low-dose-rate brachytherapy monotherapy and 474 patients underwent low-dose-rate brachytherapy with external beam radiation therapy. Logistic regression analysis was carried out to identify predictive factors for postimplant D90 decline. The cut-off value of the D90 decline was set at 170 Gy and 130 Gy in the low-dose-rate brachytherapy monotherapy group and low-dose-rate brachytherapy with external beam radiation therapy group, respectively.

RESULTS

On multivariate analysis, neoadjuvant androgen deprivation therapy was identified as an independent predictive factor for the decline of postimplant D90 in both the low-dose-rate brachytherapy monotherapy group (P < 0.001) and low-dose-rate brachytherapy with external beam radiation therapy group (P = 0.003). Prostate volume changes and computed tomography/transrectal ultrasound prostate volume ratio were significantly and negatively correlated with the postimplant D90. The prostate volume changes and computed tomography/transrectal ultrasound prostate volume ratio were significantly higher in patients with neoadjuvant androgen deprivation therapy than those without neoadjuvant androgen deprivation therapy (P < 0.001).

CONCLUSIONS

Neoadjuvant androgen deprivation therapy decreased postimplant D90 with substantial prostate gland swelling after low-dose-rate brachytherapy. When neoadjuvant androgen deprivation therapy is required to reduce prostate volume for patients with large prostate glands and offer adequate local control for patients with high-risk prostate cancer before low-dose-rate brachytherapy, intraoperative D90 adjustment might be necessary.

Erectile dysfunction and sexual quality of life in patients who underwent low-dose-rate brachytherapy alone for prostate cancer

This study evaluated erectile function and sexual quality of life (QoL), and predictive factors for erectile dysfunction (ED) and the deterioration of sexual QoL in 70 patients who underwent low-dose-rate brachytherapy (LDR-BT) alone for prostate cancer without androgen deprivation therapy. Erectile function and sexual QoL were evaluated before and 1, 3, 6, 12, 24, 36, 48 and 60 months after LDR-BT. Binary logistic regression analysis was used to determine whether age, prostate volume, hypertension, diabetes, Brinkman's index, testosterone, baseline Sexual Health Inventory for Men (SHIM) score and post-implant dosimetry parameters could predict ED and deterioration of sexual QoL at 24 and 60 months after LDR-BT. After 24 and 60 months, ED was noted in 39 of 70 patients and 42 of 64 patients respectively. Furthermore, sexual QoL worsened in 42 of 70 and 43 of 64 patients respectively. Baseline SHIM score was identified as a significant predictor of ED (24 months: odds ratio [OR]: 0.83, p = 0.02; 60 months: OR: 0.83, p = 0.03) and the deterioration of sexual QoL (24 months: OR: 0.84, p = 0.03). LDR-BT for prostate cancer promoted decreased erectile function and sexual QoL, with high preimplant potency being a significant predictor of ED and the deterioration of sexual QoL.

Comparison of disease-specific quality of life in prostate cancer patients treated with low-dose-rate brachytherapy: A randomized controlled trial of silodosin versus naftopidil

OBJECTIVES

To compare the effects of naftopidil and silodosin administration on the quality of life of patients with prostate cancer who underwent low-dose-rate brachytherapy.

METHODS

In total, 141 men diagnosed with localized prostate cancer who were treated with low-dose-rate brachytherapy were enrolled. Patients were randomized (1:1) to the naftopidil (75 mg/day, n = 63) or silodosin group (8 mg/day, n = 64). Naftopidil and silodosin were administered 1 day after low-dose-rate brachytherapy, and were continued for at least 3 months. Using the University of California at Los Angeles Prostate Cancer Index and Sexual Health Inventory for Men scores, the mean changes and rates of deterioration from baseline were compared. The deterioration rates in the quality of life of patients at 1 and 3 months after low-dose-rate brachytherapy were evaluated based on the minimal important difference.

RESULTS

The rates of deterioration from baseline to 1 and 3 months after low-dose-rate brachytherapy were not significantly different between the two groups in terms of urinary function, urinary bother, bowel bother, sexual function or Sexual Health Inventory for Men scores. In contrast, there were significant differences in bowel function (naftopidil 1 month, 52%; 3 months, 52%; silodosin 1 month, 28%; 3 months, 34%; 1 month, P < 0.01; 3 months, P = 0.048) and sexual bother (naftopidil 3 months, 11%; silodosin 3 months, 29%; P = 0.01).

CONCLUSIONS

Naftopidil and silodosin provide different disease-specific quality of life outcomes in patients undergoing, especially in terms of bowel function and sexual bother. These findings can help in the selection of α-1 adrenoceptor antagonists after low-dose-rate brachytherapy.

Factors affecting urinary frequency after low-dose-rate brachytherapy for prostate cancer

OBJECTIVES

Lower urinary tract symptoms are transiently exacerbated by low-dose-rate brachytherapy (LDR-BT) for prostate cancer and recover to pretreatment levels 1 year thereafter. Generally, these symptoms are influenced by temperature. We aimed to search for factors affecting the lower urinary tract symptoms after seed implant including seasons.

METHODS

We retrospectively enrolled 812 patients who underwent LDR-BT at Nara Medical University Hospital from January 2010 to December 2018 and for whom the International Prostate Symptom Score, Overactive Bladder Symptom Score, and frequency volume charts were available. We investigated the relationships between lower urinary tract symptoms, 24-hours urinary frequency, 24-hours urinary volume before and after seed implant, radiation dose, and season of seed implant.

RESULTS

The mean age was 69.5 years. The mean prostate volume was 24.2 mL. The International Prostate Symptom Score, Overactive Bladder Symptom Score, and 24-hours urinary frequency increased until 3 months and gradually decreased over 6 months after seed implant. Multiple linear regression analysis revealed that 24-hours urinary frequency at 3 months after seed implant was significantly influenced by external beam radiotherapy, larger prostate volume before implant, higher 24-hours urinary frequency at baseline, larger 24-hours urinary volume at 3 months after implant, and performance of implant in summer.

CONCLUSIONS

Lower urinary tract symptoms worsened 3 months after seed implant of LDR-BT regardless of the season of implant. The urinary frequency 3 months after seed implant was slightly lower when seed implant was performed in the summer.

Coverage of the external prostatic region by the hybrid method compared with the conventional method of prostate low-dose-rate brachytherapy: A randomized controlled study

OBJECTIVES

To compare the dose evaluation parameters between conventional (using loose seed alone) and hybrid (using loose seeds in combination with stranded seeds) low-dose rate brachytherapy for prostate cancer.

METHODS

Between 2014 and July 2016, a total of 219 patients who underwent low-dose rate brachytherapy were enrolled in a randomized controlled trial (trial number: UMIN 000012780). Patients were randomized and allocated to two groups (conventional method vs hybrid method). Post-dosimetric parameters (%D90, minimal percentage of the dose received by 90% of the prostate gland; V100, percentage of the prostate volume receiving 100% of the prescribed minimal peripheral dose; V150, percentage of the prostate volume receiving 150% of the prescribed minimal peripheral dose; %UD30, minimal percentage of the dose received by 30% of the urethra; R100, rectal volume [mL] receiving 100% of the prescribed dose) calculated at 1 month after seed implantation by computed tomography scan were compared between the two groups, as well as the post-dosimetric parameters using the planning target volume of the prostate + 5-mm margin.

RESULTS

Regarding dose evaluation parameters, the prostate dose (%D90, V100, V150) and the urethral dose (%UD30) were not significantly different between the two groups, whereas V100 (+5-mm margin) and %D90 (+5-mm margin) were significantly higher in the hybrid method group compared with the conventional method group (P < 0.001).

CONCLUSION

The present randomized study shows that the hybrid method of low-dose rate brachytherapy can achieve a higher coverage of the periprostatic region compared with the conventional method while maintaining an acceptable level of urethral and rectal doses.

Biochemical control of the combination of cyclooxygenase-2 inhibitor and 125 I-brachytherapy for prostate cancer: Post hoc analysis of an open-label controlled randomized trial

OBJECTIVES

To evaluate the use of cyclooxygenase-2 inhibitors in patients receiving low-dose-rate brachytherapy for prostate cancer.

METHODS

A total of 310 patients with prostate cancer (cT1c-3aN0M0) who received low-dose-rate brachytherapy between May 2010 and July 2013 were enrolled and allocated to one of the two treatment groups (tamsulosin alone 0.2 mg/day for 6 months vs tamsulosin 0.2 mg/day for 6 months plus celecoxib 200 mg/day for 3 months). The primary end-point was the chronological change in international prostate symptom score, and the number of patients was assessed for the primary end-point. Biochemical recurrence-free, cancer-specific survival and overall survival rates 5 years after the last patient received low-dose-rate brachytherapy were retrospectively examined.

RESULTS

The median follow-up period after low-dose-rate brachytherapy was 72.0 months (range 3-99 months). A total of 12 (3.9%) patients experienced biochemical recurrence. The biochemical recurrence-free rate in the celecoxib group (5-year biochemical recurrence-free rate 98.5%) was significantly better (log-rank test P = 0.023, 95% confidence interval 0.07-0.63, hazard ratio 0.20) than that in the tamsulosin group (5-year biochemical recurrence-free rate 93.4%). None of the patients died from prostate cancer. However, 14 (4.5%) patients died of other causes. No significant difference was observed in terms of overall survival between the celecoxib and tamsulosin groups.

CONCLUSIONS

The combination of cyclooxygenase-2 inhibitor and low-dose-rate brachytherapy can contribute to a better biochemical control of prostate cancer.

Prostate-specific antigen bounce after 125I-brachytherapy for prostate cancer is a favorable prognosticator in patients who are biochemical recurrence-free at 4 years and correlates with testosterone

BACKGROUND

Because patients with prostate-specific antigen (PSA) bounce do not experience biochemical recurrence (BCR) until PSA bounce occurs, the period until PSA bounce ends can be considered the so-called lead-time bias. Therefore, we evaluated differences in BCR-free rate in prostate cancer patients who were BCR-free 4 years after 125I-brachytherapy alone. Furthermore, we evaluated predictors for PSA bounce and the correlation between testosterone and PSA bounce.

METHODS

From 2004 to 2012, 256 patients with prostate adenocarcinoma underwent 125I-brachytherapy alone. PSA and testosterone levels were monitored prior to 125I-brachytherapy, at 1, 3, 6, 12, 18, 24, 30, 36, 42, 48, 54 and 60 months after 125I-brachytherapy and yearly after 5-year follow-up. PSA bounce was defined as ≥0.2 ng/ml increase above the interval PSA nadir, followed by a decrease to nadir or below.

RESULTS

BCR-free rate in patients with PSA bounce (100% 7-year BCR-free rate) was significantly better (P < 0.044) than that in patients without PSA bounce (95.7% 7-year BCR-free rate) in patients who were BCR-free 4 years after 125I-brachytherapy alone (n = 223). Age was the only predictor (odds ratio: 0.93, 95% confidence interval: 0.88-0.98, P = 0.004) for PSA bounce (n = 177). The testosterone level at PSA bounce was significantly higher (P = 0.036) than that at nadir before PSA bounce (87 cases).

CONCLUSIONS

Patients with PSA bounce had good BCR-free rate even in patients who were BCR-free 4 years after 125I-brachytherapy alone. Testosterone levels were higher at PSA bounce; increased testosterone levels may be a cause of PSA bounce.

Low-dose-rate brachytherapy for prostate cancer: A 15-year experience in Japan

The history of prostate brachytherapy has passed one century. In 1983, modern low-dose-rate prostate brachytherapy using a transrectal ultrasound-guided procedure was introduced. In the early 1990s, low-dose-rate brachytherapy was introduced and rapidly spread across the USA due to its excellent oncological control, cost-effectiveness and technically easy procedure. Since low-dose-rate brachytherapy was introduced in Japan (2003), over 15 years have passed. More than 43 000 patients have undergone low-dose-rate brachytherapy. Japanese urologists and radiation oncologists are on course with leading brachytherapists in the USA. A nationwide prospective cohort study, J-POPS, was initiated in 2005. The J-POPS group also provides educational programs including an annual novel training course in low-dose-rate brachytherapy to familiarize urologists, radiation oncologists and pathologists with the procedure. Important information on Japanese patients has accumulated, especially by the J-POPS study group. The Japanese investigators reported excellent oncological outcomes of low-dose-rate brachytherapy, showing equivalent or superior efficacy to surgery in low- to intermediate-risk patients, and superior efficacy in high-risk patients using the surgery biochemical recurrence definition (prostate-specific antigen cut-off value of 0.2 ng/mL). Two randomized controlled studies (SHIP study: intermediate risk, and TRIP study: high risk) carried out by the J-POPS group are ongoing, and an additional follow-up study (J-POPS 2 study) has been started to evaluate survival outcomes over longer follow-up periods. Low-dose-rate brachytherapy is expected to provide a survival benefit, which must be confirmed by further studies with longer follow-up periods in the future.

Localized prostate cancer with pelvic arteriovenous malformation treated with low-dose-rate brachytherapy after transcatheter embolization: Two case reports

Background

We describe two patients who underwent low‐dose‐rate prostate brachytherapy after embolization for pelvic arteriovenous malformation.

Case presentation

Case 1: A 76‐year‐old man was referred for definitive treatment of intermediate‐risk prostate cancer (prostate‐specific antigen 8.667 ng/mL, cT2aN0M0, Gleason score 3 + 4 = 7). We planned low‐dose‐rate brachytherapy. However, magnetic resonance imaging and computed tomography demonstrated a large pelvic arteriovenous malformation. We performed embolization of the arteriovenous malformation before initiating treatment to lower the risk of rupture of the arteriovenous malformation during low‐dose‐rate brachytherapy. Case 2: A 69‐year‐old man was referred for the definitive treatment of high‐risk prostate cancer (prostate‐specific antigen 5.81 ng/mL, cT2aN0M0, Gleason score 4 + 4 = 8) with a pelvic arteriovenous malformation. Similar to Case 1, we performed embolization of the arteriovenous malformation before initiating treatment. In both cases, low‐dose‐rate brachytherapy could be performed without complications.

Conclusions

Low‐dose‐rate brachytherapy after transcatheter embolization of pelvic arteriovenous malformations can safely and effectively treat localized prostate cancer with pelvic arteriovenous malformations.

Quality of life in patients who underwent 125I brachytherapy, 125I brachytherapy combined with three-dimensional conformal radiation therapy, or intensity-modulated radiation therapy, for prostate cancer

The purpose of this study was to evaluate quality of life (QOL) in prostate cancer patients treated with 125I brachytherapy (BT), 125I brachytherapy combined with 3D conformal radiation therapy (BT+3D-CRT), or intensity-modulated radiation therapy (IMRT). We evaluated disease-related QOL in patients who underwent BT, BT+3D-CRT, or IMRT, using the Expanded Prostate Cancer Index Composite questionnaire before treatment and at 3 and 24 months post-treatment. Multivariate analyses were conducted to determine factors associated with a minimum important difference (MID) in urinary, bowel, sexual, and hormone domain scores at 3 and 24 months post-treatment. Of 558 enrolled patients (IMRT, 123; BT, 230; and BT+3D-CRT, 205), urinary domain scores showed a MID after BT, BT+3D-CRT and IMRT at 3 months in 69%, 84% and 25% of patients, respectively, and at 24 months in 43%, 54% and 28% of patients, respectively. On multivariate analysis, BT+3D-CRT [3 months: odds ratio (OR) = 12.7; P < 0.001; 24 months: OR = 3.29; P = 0.001] and BT (3 months: OR = 6.28; P < 0.001 and 24 months: OR = 2.22; P = 0.027) were associated with more severely worsened urinary QOL than IMRT. Bowel domain scores showed a MID at 3 months after BT, BT+3D-CRT, and IMRT in 37%, 68% and 41% of patients, respectively, and at 24 months in 29%, 46% and 43% of patients, respectively. On multivariate analysis, BT+3D-CRT (3 months: OR = 4.20; P < 0.001 and 24 months: OR = 2.63; P < 0.001) and IMRT (24 months: OR = 1.98; P = 0.029) were associated with more severely worsened bowel QOL than was BT. Information about the changes in QOL outcomes associated with radiotherapy modalities could guide treatment decisions.

Changes in lower urinary tract symptoms after iodine-125 brachytherapy for prostate cancer

•

Patients who received BT experienced acute urinary morbidity 3 months after BT of the prostate.

•

Acute urinary symptoms gradually improved with time and returned to BL at 36 months.

•

Storage symptoms take longer to return to BL compared with voiding symptoms.

Purpose

To investigate chronological changes in lower urinary tract symptoms (LUTS) in patients who received iodine-125 brachytherapy (BT) for prostate cancer.

Methods

We enrolled 706 patients who received BT. Of these, 265 (38%) received BT combined with external beam radiation therapy (EBRT). An International Prostate Symptom Score (IPSS), IPSS quality of life (IPSS-QOL) score, and overactive bladder symptom score (OABSS) were recorded before BT (baseline, BL), and 1, 3, 6, 12, 24, 36, 48, and 60 months after BT. The sum of frequency (2), urgency (4) and nocturia (7) of the IPSS questionnaire was defined as the storage symptoms score, whereas the sum of emptying (1), intermittency (3), weak stream (5), and hesitancy (6) was defined as the voiding symptom score.

Results

Total IPSS significantly increased at 3 months following BT compared with BL (mean score: 17.1 vs. 7.99, P < 0.001) and returned to BL by 36 months. The storage symptom score did not return to BL 36 months after BT. Total OABSS significantly increased 3 months after BT compared with BL (mean score: 6.52 vs. 3.45, P < 0.001), and returned to BL 48 months after BT. The IPSS-QOL score was the highest score (mean score: 2.46 vs. 3.9, P < 0.001) 3 months after BT and returned to BL 48 months after BT, however the IPSS-QOL score was lower than BL (mean score: 2.01 vs 2.46, P < 0.001) at 60 months. The risk factors for LUTS within 1 year after BT were BL IPSS (P < 0.001) and PV (P < 0.001). Patients who received combined EBRT experienced transient storage symptoms 24 and 36 months after BT, whereas those who received BT alone did not. However, the storage symptom score of the patients who received combined EBRT was improving 48 months after BT and eventually showed no significant difference compared with those treated with BT alone.

Conclusion

Three months after BT, LUTS, including storage symptoms, deteriorated the most but improved with time. The urinary symptom in patients who received combined EBRT can potentially flare again in 24 and 36 months after BT. Knowledge of changes in LUTS associated with BT may influence treatment recommendations and enable patients to make better-informed decisions.

Quality of life worsened the most severely in patients immediately after intensity-modulated radiotherapy for prostate cancer

Purpose

The aim of this study was to evaluate the chronological changes in lower urinary tract symptoms (LUTSs), disease-related quality of life (QOL), and health-related QOL (HR-QOL) of patients who received intensity-modulated radiotherapy (IMRT).

Patients and methods

In 121 patients who had received IMRT and were followed up for >2 years, the International Prostate Symptom Score (IPSS), Overactive Bladder Symptom Score (OABSS), Expanded Prostate Cancer Index Composite (EPIC), and 8-Item Short-Form Health Survey (SF-8) were used before IMRT, at the halfway point in IMRT, immediately after IMRT, and 1–24 months after the completion of IMRT.

Results

The IPSS and OABSS and the urinary and bowel domains of the EPIC indicated that QOL worsened at the halfway point in IMRT, further worsened more severely immediately after IMRT, and then improved. The sexual domain of the EPIC significantly decreased at the halfway point in IMRT, which significantly lowered until 24 months. The scores of physical functioning, role physical, bodily pain, vitality, social functioning, and role emotional domains in the SF-8 significantly decreased and reached their lowest points immediately after IMRT.

Conclusion

QOL worsened the most severely in patients immediately after IMRT for prostate cancer. This knowledge can influence treatment recommendations and enable patients to make better informed decisions.

The impact of the definition of biochemical recurrence following salvage radiotherapy on outcomes and prognostication in patients with recurrent prostate cancer after radical prostatectomy: a comparative study of three definitions

Purpose

The clinical management and follow-up of patients with recurrent prostate cancer after salvage radiotherapy (SRT) has not yet been established, and no standardized definition of biochemical recurrence (BCR) after SRT exists. We compared the impact of applying three different definitions of BCR following SRT on patient outcomes and prognostication.

Subjects

Patients who received salvage androgen-deprivation therapy before the completion of SRT were excluded. The data of 118 men who had undergone salvage radiation as monotherapy for BCR after radical prostatectomy were reviewed. In all patients, SRT comprised irradiation to the prostatic bed (70 Gy) using three-dimensional conformal radiotherapy techniques. Treatment outcomes, including BCR-free survival and prognostic factors, were analyzed and compared among three definitions: The Nara, Radiation Therapy Oncology Group (RTOG) 9601, and GETUG-AFU 16 definitions.

Results

The BCR rate differed significantly among the applied definitions. Multivariate analyses identified the same four independent prognostic factors, including primary Gleason pattern 4 or 5, negative resection margin, prostate-specific antigen (PSA) level before SRT 0.5 or more, and PSA doubling time before SRT <6 months, using the RTOG 9601 and GETUG-AFU 16 definitions, whereas only two of the four factors were identified using the Nara definition. Although the results obtained using the RTOG 9601 and GETUG-AFU 16 definitions were similar, the prognostic value of the four factors differed. According to the RTOG 9601 definition of BCR, a negative resection margin on prostatectomy specimens and short PSA doubling time before SRT were associated with no subsequent response in PSA level.

Conclusions

The applied definition of BCR after SRT can influence the reported BCR-free rate and the potential prognostic factors. Establishment of the standardized definition is needed for the optimal management of patients with recurrent prostate cancer undergoing SRT.

Assessment of lower urinary symptom flare with overactive bladder symptom score and International Prostate Symptom Score in patients treated with iodine-125 implant brachytherapy: long-term follow-up experience at a single institute

Background

The aim of this study was to evaluate the combined use of the overactive bladder symptom score (OABSS) and International Prostate Symptom Score (IPSS) as an assessment tool for urinary symptom flare after iodine-125 (¹²⁵I) implant brachytherapy. The association between urinary symptom flare and prostate-specific antigen (PSA) bounce was investigated.

Methods

Changes in the IPSS and OABSS were prospectively recorded in 355 patients who underwent seed implantation. The percentage distribution of patients according to the difference between the flare peak and post-implant nadir was plotted to define significant increases in the scores. The clinicopathologic characteristics, treatment parameters, and post-implant dosimetric parameters were compared between the non-flare and flare groups. PSA bounce was defined as an elevation of ≥0.1 ng/mL or ≥0.4 ng/mL compared to the previous lowest value, followed by a decrease to a level at or below the pre-bounce value.

Results

A clinically significant increase required an IPSS increase of at least 12 points and an OABSS increase of at least 6 points based on a time-course analysis of total scores and the QOL index. Assessment only by IPSS failed to detect 40 patients (11%) who had urinary symptom flare according to the OABSS. Univariate and multivariate analyses revealed that patients treated with higher biologically effective doses and those without diabetes mellitus had higher risks of urinary flare. There was no statistical correlation between the incidence and time of urinary symptom flare onset and that of a PSA bounce.

Conclusions

To our knowledge, this is the first report to prove the clinical potential of the OABSS as an assessment tool for urinary symptom flare after seed implantation. Our findings showed that persistent lower urinary tract symptoms after seed implantation were attributed to storage rather than to voiding issues. We believe that assessment with the OABSS combined with the IPSS would aid in decision-making in terms of timing, selection of a treatment intervention, and assessment of the outcome.

Electronic supplementary material

The online version of this article (doi:10.1186/s12894-017-0251-1) contains supplementary material, which is available to authorized users.

Use of alpha-1 adrenoceptor antagonists in patients who underwent low-dose-rate brachytherapy for prostate cancer - a randomized controlled trial of silodosin versus naftopidil

Background

To evaluate the effect of two different alpha-1 adrenoceptor antagonists on lower urinary tract symptoms in patients who underwent LDR-brachytherapy.

Methods

A total of 141 patients who had been clinically diagnosed with localized prostate cancer and underwent LDR-brachytherapy were enrolled. Patients were randomized and allocated to two groups (silodosin 8 mg vs. naftopidil 75 mg). The primary endpoint was a change in the international prostate symptom score (IPSS) at 3 months after seed implantation. Secondary endpoints included the recovery rate of IPSS at 12 months after seed implantation, the change in IPSS and overactive bladder symptom score, uroflowmetric parameters, and frequency volume chart (FVC). To determine independent variables that can predict IPSS recovery, logistic regression analysis was carried out.

Results

The mean change in the IPSS at 3 months after seed implantation in both groups was ⊿10.6 (naftopidil) and ⊿10.4 (silodosin), respectively. There was not a significant difference between the two groups (p=0.728). An increase in urinary frequency and a decrease in total urinated volume and mean voided volume were observed in FVC for 12 months after seed implantation. Multivariate analysis revealed that the urethral dose (UD30) was an independent predictive parameter of IPSS recovery. Patients with UD30 < 200Gy showed a higher recovery rate of IPSS at 12 months after seed implantation.

Conclusion

There was no significant difference of serial change in IPSS between silodosin and naftopidil during the first year after seed implantation. A lower dose on the urethra was an independent predictor of IPSS recovery at 12 months after seed implantation.

Urethral toxicity after LDR brachytherapy: experience in Japan

Urinary toxicity is common after low-dose-rate (LDR) brachytherapy, and the resolution of urinary toxicity is a concern. In particular, urinary frequency is the most common adverse event among the urinary toxicities. We have previously reported that approximately 70% of patients experience urinary frequency during the first 6 months after seed implantation. Most urinary adverse events were classified as Grade 1, and Grade 2 or higher adverse events were rare. The incidence of urinary retention was approximately 2-4%. A high International Prostate Symptom Score before seed implantation was an independent predictor of acute urinary toxicity of Grade 2 or higher. Several previous reports from the United States also supported this trend. In Japan, LDR brachytherapy was legally approved in 2003. A nationwide prospective cohort study entitled Japanese Prostate Cancer Outcome Study of Permanent Iodine-125 Seed Implantation was initiated in July 2005. It is an important issue to limit urinary toxicities in patients who undergo LDR brachytherapy.

Salvage brachytherapy for seminal vesicle recurrence after initial brachytherapy for prostate cancer: a case report

Background

To report the efficacy and safety of salvage brachytherapy for seminal vesicle recurrence after initial brachytherapy in a patient with prostate cancer. As far as we know, this is a first report of salvage brachytherapy for seminal vesicle recurrence in Japan.

Case presentation

A 70-year-old Japanese man with low-risk prostate cancer received low-dose-rate brachytherapy. Forty-two months after the seed implantation, he showed biochemical recurrence based on the nadir + 2 ng/mL definition. The prostate specific antigen (PSA) level was 5.11 ng/mL at 58 months after seed implantation. A saturation biopsy of the prostate showed no recurrence. Systemic screening also showed no distant metastases. However, T2-weighted magnetic resonance imaging (MRI) demonstrated a low intensity area at the base of the right seminal vesicle, which was strongly suggestive of recurrence. Sixty months after the initial therapy, a seminal vesicle biopsy confirmed recurrence with a Gleason score of 4 + 3 before salvage brachytherapy was performed. The prescribed dose was 145 Gy, the same as the dose of the initial therapy. One month later, the PSA level had rapidly declined to 0.898 ng/mL without androgen deprivation therapy. Ten months after the salvage brachytherapy, the PSA level reached 0.078 ng/mL. No adverse events were seen during the follow-up period.

Conclusions

We experienced a patient who was successfully treated with salvage brachytherapy for seminal vesicle recurrence. Salvage brachytherapy is one of the promising therapeutic options for recurrence after initial brachytherapy.

Proposed salvage treatment strategy for biochemical failure after radical prostatectomy in patients with prostate cancer: a retrospective study

BACKGROUND

Treatment options for patients with recurrent disease after radical prostatectomy include salvage radiotherapy of the prostatic bed and/or androgen deprivation therapy. To establish an effective treatment strategy for recurrent disease after radical prostatectomy, we retrospectively analyzed the outcome of salvage radiation monotherapy in such cases.

METHODS

Data from 61 men who had undergone salvage radiation monotherapy for biochemical recurrent disease after radical prostatectomy were retrospectively reviewed. In all patients, salvage radiotherapy consisted of iraradiation to the prostatic bed (70 Gy) using three-dimensional conformal radiotherapy techniques. Treatment outcome was analyzed to identify predictive factors of salvage radiotherapy.

RESULTS

The biochemical recurrence-free survival after salvage radiation monotherapy at 2 and 5 years was 55% and 38%, respectively. Cox proportional regression models revealed that the independent predictive factors for biochemical recurrence were Gleason Score ≥ 8, negative surgical margin, and PSA velocity ≥ 0.38 ng/mL/year. Negative surgical margin and PSA velocity ≥ 0.8 ng/mL/year were significantly associated with poor response in the serum PSA levels after salvage radiotherapy.

CONCLUSIONS

Based on our findings, we propose a treatment strategy for biochemical recurrent disease after radical prostatectomy. Patients with Gleason score ≤ 7, positive surgical margin, and PSA velocity < 0.38 ng/mL/year are categorized the most favorable group, so that eradication by salvage radiation monotherapy could be expected. Other patients could be divided to two groups depending on surgical margin status and PSA velocity: 1) patients who might require combination of SRT and short-term androgen deprivation therapy and 2) patients who should be treated by androgen deprivation monotherapy.

The biochemical recurrence-free rate in patients who underwent prostate low-dose-rate brachytherapy, using two different definitions

BACKGROUND

To assess the biochemical recurrence (BCR)-free rate in patients who underwent prostate low-dose-rate brachytherapy (LDR-brachytherapy), using two different definitions (Phoenix definition and PSA ≥ 0.2 ng/mL).

METHODS

Two hundreds and three patients who were clinically diagnosed with localized prostate cancer (cT1c-2cN0M0) and underwent LDR-brachytherapy between July 2004 and September 2008 were enrolled. The median follow-up period was 72 months. We evaluated the BCR-free rate using the Phoenix definition and the PSA cut-off value of 0.2 ng/mL, as in the definition for radical prostatectomy. To evaluate an independent variable that can predict BCR, Cox's proportional hazard regression analysis was carried out.

RESULTS

The BCR-free rate in patients using the Phoenix definition was acceptable (5-year: 92.8%). The 5- year BCR-free rate using the strict definition (PSA ≥ 0.2 ng/mL) was 74.1%. Cox's proportional hazard regression analysis showed that a higher biological effective dose (BED) of ≥180 Gy2 was the only independent variable that could predict BCR (HR: 0.570, 95% C.I.: 0.327-0.994, p = 0.048). Patients with a higher BED (≥180 Gy2) had a significantly higher BCR-free rate than those with a lower BED (<180 Gy2) (5-year BCR-free rate: 80.5% vs. 67.4%).

CONCLUSIONS

A higher BED ≥180 Gy2 promises a favorable BCR-free rate, even if the strict definition is adopted.

[Radiation therapy for malignant lymphoma]

Malignant lymphoma is usually radiosensitive and radiation therapy is an effective modality for local control of lymphoma. However, lymphoma is a typical systemic disease, and chemotherapy is performed for many cases. Recently, the late adverse events associated with radiotherapy (especially extended field radiation therapy), such as cardiovascular disease and secondary cancers, become a serious problem for long-term lymphoma survivors. In combination with chemotherapy, it is possible to reduce both the treatment volume and the overall treatment dose to minimise the risks of late adverse events.

Posttreatment cut-off levels of squamous cell carcinoma antigen as a prognostic factor in patients with locally advanced cervical cancer treated with radiotherapy

OBJECTIVE

The aim of the present study was to assess prognostic factors for patients with locally advanced cervical cancer treated with radiotherapy as the primary treatment and to assess the posttreatment cut-off levels of squamous cell carcinoma antigen (SCC-Ag) to predict three-year overall survival (OS) rates.

METHODS

One hundred and twenty-eight patients with cervical squamous cell carcinoma (International Federation of Gynecology and Obstetrics [FIGO] stage IIB-IVA) treated using radiotherapy or concurrent chemoradiotherapy were identified. Of these patients, 116 who had SCC-Ag levels >1.5 ng/mL prior to treatment were analyzed retrospectively.

RESULTS

Median age was 68 years (range, 27 to 79 years). The complete response rate was 70.7% and the three-year OS rate was 61.1%. The median levels of pretreatment and posttreatment SCC-Ag were 11.5 ng/mL (range, 1.6 to 310.0 ng/mL) and 0.9 ng/mL (range, 0.4 to 41.0 ng/mL), respectively. Multivariate analysis showed that pretreatment anemia (p=0.041), pelvic lymph node metastasis (p=0.016) and posttreatment SCC-Ag levels (p=0.001) were independent prognostic factors for three-year OS. The SCC-Ag level cut-off point for three-year OS rates, calculated using a receiver operating characteristic curve, was 1.15 ng/mL (sensitivity, 80.0%; specificity, 74.0%).

CONCLUSION

Pretreatment anemia and pelvic lymph node metastasis are poor prognostic factors in locally advanced cervical cancer. Furthermore, posttreatment SCC-Ag levels <1.15 ng/mL predicted better three-year OS rates.

Efficacy of FDG-PET for defining gross tumor volume of head and neck cancer

We analyzed the data for 53 patients with histologically proven primary squamous cell carcinoma of the head and neck treated with radiotherapy between February 2006 and August 2009. All patients underwent contrast-enhanced (CE)-CT and (18)F-fluorodeoxyglucose (FDG)-PET before radiation therapy planning (RTP) to define the gross tumor volume (GTV). The PET-based GTV (PET-GTV) for RTP was defined using both CE-CT images and FDG-PET images. The CE-CT tumor volume corresponding to a FDG-PET image was regarded as the PET-GTV. The CE-CT-based GTV (CT-GTV) for RTP was defined using CE-CT images alone. Additionally, CT-GTV delineation and PET-GTV delineation were performed by four radiation oncologists independently in 19 cases. All four oncologists did both methods. Of these, PET-GTV delineation was successfully performed in all 19 cases, but CT-GTV delineation was not performed in 4 cases. In the other 15 cases, the mean CT-GTV was larger than the PET-GTV in 10 cases, and the standard deviation of the CT-GTV was larger than that of the PET-GTV in 10 cases. Sensitivity of PET-GTV for identifying the primary tumor was 96%, but that of CT-GTV was 81% (P < 0.01). In patients with oropharyngeal cancer and tongue cancer, the sensitivity of CT-GTV was 63% and 71%, respectively. When both the primary lesions and the lymph nodes were evaluated for RTP, PET-GTV differed from CT-GTV in 19 cases (36%). These results suggested that FDG-PET is effective for defining GTV in RTP for squamous cell carcinoma of the head and neck, and PET-GTV evaluated by both CE-CT and FDG-PET images is preferable to CT-GTV by CE-CT alone.

Periodical assessment of genitourinary and gastrointestinal toxicity in patients who underwent prostate low-dose-rate brachytherapy

BACKGROUND

To compare the periodical incidence rates of genitourinary (GU) and gastrointestinal (GI) toxicity in patients who underwent prostate low-dose-rate brachytherapy between the monotherapy group (seed implantation alone) and the boost group (in combination with external beam radiation therapy (EBRT)).

METHODS

A total of 218 patients with a median follow-up of 42.5 months were enrolled. The patients were divided into 2 groups by treatment modality, namely, the monotherapy group (155 patients) and the boost group (63 patients). The periodical incidence rates of GU and GI toxicity were separately evaluated and compared between the monotherapy group and the boost group using the National Cancer Institute - Common Terminology Criteria for Adverse Events, version 3.0. To elucidate an independent factor among clinical and postdosimetric parameters to predict grade 2 or higher GU and GI toxicity in the acute and late phases, univariate and multivariate logistic regression analyses were carried out.

RESULTS

Of all patients, 78.0% showed acute GU toxicity, and 7.8% showed acute GI toxicity, while 63.8% showed late GU toxicity, and 21.1% showed late GI toxicity. The incidence rates of late GU and GI toxicity were significantly higher in the boost group. Multivariate analysis showed that the International Prostate Symptom Score (IPSS) before seed implantation was a significant parameter to predict acute GU toxicity, while there were no significant predictive parameters for acute GI toxicity. On the other hand, combination with EBRT was a significant predictive parameter for late GU toxicity, and rectal volume (mL) receiving 100% of the prescribed dose (R100) was a significant predictive parameter for late GI toxicity.

CONCLUSIONS

The boost group showed higher incidence rates of both GU and GI toxicity. Higher IPSS before seed implantation, combination with EBRT and a higher R100 were significant predictors for acute GU, late GU and late GI toxicity.

Minimal percentage of dose received by 90% of the urethra (%UD90) is the most significant predictor of PSA bounce in patients who underwent low-dose-rate brachytherapy (LDR-brachytherapy) for prostate cancer

BACKGROUND

To clarify the significant clinicopathological and postdosimetric parameters to predict PSA bounce in patients who underwent low-dose-rate brachytherapy (LDR-brachytherapy) for prostate cancer.

METHODS

We studied 200 consecutive patients who received LDR-brachytherapy between July 2004 and November 2008. Of them, 137 patients did not receive neoadjuvant or adjuvant androgen deprivation therapy. One hundred and forty-two patients were treated with LDR-brachytherapy alone, and 58 were treated with LDR-brachytherapy in combination with external beam radiation therapy. The cut-off value of PSA bounce was 0.1 ng/mL. The incidence, time, height, and duration of PSA bounce were investigated. Clinicopathological and postdosimetric parameters were evaluated to elucidate independent factors to predict PSA bounce in hormone-naïve patients who underwent LDR-brachytherapy alone.

RESULTS

Fifty patients (25%) showed PSA bounce and 10 patients (5%) showed PSA failure. The median time, height, and duration of PSA bounce were 17 months, 0.29 ng/mL, and 7.0 months, respectively. In 103 hormone-naïve patients treated with LDR-brachytherapy alone, and univariate Cox proportional regression hazard model indicated that age and minimal percentage of the dose received by 30% and 90% of the urethra were independent predictors of PSA bounce. With a multivariate Cox proportional regression hazard model, minimal percentage of the dose received by 90% of the urethra was the most significant parameter of PSA bounce.

CONCLUSIONS

Minimal percentage of the dose received by 90% of the urethra was the most significant predictor of PSA bounce in hormone-naïve patients treated with LDR-brachytherapy alone.

Changes of tumor size and tumor contrast enhancement during radiotherapy for non-small-cell lung cancer may be suggestive of treatment response

We evaluated sequential dynamic contrast-enhanced CT (DCE-CT) scans to assess the possibility of early prediction of treatment responses by quantifying the tumor size reduction and the change in tumor enhancement during and after a course of radiotherapy (RT). Thirty-nine patients with non-small-cell lung cancer were treated with RT for initial treatment. DCE-CT scan was performed within one week before the beginning of treatment, after 17 or 18 fractions (34 or 36 Gy), and 1 week and 1 month after the end of RT. The correlation between the relative decrease in tumor diameter and that in the attenuation value was evaluated. Nineteen patients were evaluated in this study. The median tumor size was 39.5 mm at the start of treatment, 30.8 mm at 34-36 Gy, and 16.1 mm 1 month after the end of RT. The relative decrease in tumor diameter at 34-36 Gy well correlated with that 1 month after treatment (r = 0.85, r: Pearson's correlation coefficient, p < 0.001). Relative change in the attenuation value at the rim of the tumor at 34-36 Gy did not significantly correlate with the change in tumor diameter 1 month after the completion of RT, but in the center of the tumor, the change of the attenuation value in the delayed phase correlated with the change in tumor diameter. The decrease of tumor diameter during RT may be predictive of treatment response. The relative change of tumor enhancement in the center of the tumor in the delayed phase correlated with tumor shrinkage 1 month after the completion of RT.