Radical external beam radiotherapy for prostate cancer in Japan: preliminary results of the changing trends in the Patterns of Care process survey between 1996-1998 and 1999-2001

OBJECTIVE: To report the preliminary results of a study to delineate the changing trends in radical external beam radiotherapy usage for prostate cancer between the 1996-1998 and 1999-2001 survey periods in Japan. METHODS: The 1996-1998 Patterns of Care Study (PCS) and the 1999-2001 PCS in Japan reviewed the detailed information on 694 patients with prostate cancer treated with radiotherapy. Of them, 298 patients with clinically localized prostate cancer treated with radical external beam radiotherapy in A1 and B1 institutions were selected for analysis (1996-1998 PCS, 117 patients; 1999-2001 PCS, 181 patients). RESULTS: High-risk prostate cancer (defined as T3-T4 tumors, a pretreatment prostate-specific antigen level >20 ng/ml, and/or poorly differentiated adenocarcinoma) was diagnosed in 82.1% of the patients in the 1996-1998 PCS and in significantly less (70.2%) of those in the 1999-2001 PCS (P = 0.021). Moreover, significantly earlier T stages (T1-T2: 49.7%) and more well-differentiated tumors (24.7%) were found between 1999 and 2001 than between 1996 and 1998 (T1-T2: 31.9%, well-differentiated tumors: 13.9%). Although only 6.1% of patients were treated with radiotherapy by patient's choice in 1996-1998, a larger proportion (32.2%) chose this treatment in 1999-2001. The median radiation dose was 65.0 Gy (range, 24-74 Gy) in 1996-1998 and increased to 69 Gy (range, 14-80 Gy) in 1999-2001. The percentage of radiation doses <60 Gy was 20.5% in 1996-1998 but only 2.2% in 1999-2001. Moreover, the incidence of treatment with total doses of > or =70 Gy was higher in 1999-2001 (43.9%) than in 1996-1998 (19.7%). These increased radiation doses were predominantly observed in B1 institutions. Although the usage of > or =10 MV was significantly increased in 1999-2001 (82.0%) compared with that in 1996-1998 (65.8%), conformal therapy administered to 52.1% of patients in 1996-1998 was almost the same (55.8%) in 1999-2001. The median number of full-time equivalent (FTE) radiation oncologists (2.4 in A1 institutions and only 0.6 in B1 institutions) in 1996-1998 increased slightly in 1999-2001 (2.7 in A1 institutions, 0.7 in B1 institutions), but remained low in B1 institutions. CONCLUSIONS: In Japan, there is a trend to fewer high-risk prostate cancer patients being treated with radical external beam radiotherapy. An increasing percentage of patients chose radiotherapy and also increased radiation doses, which might reflect the growing acceptance of radical external beam radiotherapy as a treatment of choice for prostate cancer in Japan. Therefore, to optimize delivery of radiotherapy, more advanced equipment and more FTE radiation oncologists are warranted.     

Radical external beam radiotherapy for prostate cancer in Japan: results of the 1999-2001 patterns of care process survey

BACKGROUND: The Patterns of Care Study evaluated standards of practice for patients with clinically localized prostate cancer treated with radiotherapy in Japan. This study examined the influence of institutional stratification on care for patients receiving radical external beam radiotherapy. METHODS: A national survey of 66 institutions was conducted using two-stage cluster sampling, and detailed information was accumulated on 283 patients who received radiotherapy between 1999 and 2001. RESULTS: In A (academic) and B (non-academic) institutions, more than 80% of patients had intermediate or unfavorable risk disease. Although there were no significant differences in disease characteristics between A and B institutions, institutional stratification significantly affected radiotherapy practice patterns, such as the use of a CT-based treatment planning (A1: 91.5%, B: 77.1%; P = 0.0007) and the use of conformal therapy (A: 56.4%, B: 24.1%; P < 0.0001). CT-based treatment planning and conformal therapy significantly influenced total radiation dose (P < 0.0001 for each). Hormonal therapy was commonly used in both A and B institutions (A: 89.0%, B: 90.7%). Many patients with a favorable prognosis (A: 62.5%, B: 91.7%) received hormonal therapy, and most patients with unfavorable risk disease (A: 93.6%, B: 91.6%) also received hormonal therapy. CONCLUSION: During the period 1999-2001, the majority of prostate cancer patients treated in Japan with radical external beam radiotherapy had advanced diseases. Institutional stratification significantly affected radiotherapy practice patterns, with the notable exception that radiotherapy was commonly combined with hormonal therapy regardless of the institutional stratification and individual risk.     

Postoperative radiotherapy for patients with prostate cancer in Japan; Changing trends in national practice between 1996-98 and 1999-2001: Patterns of care study for prostate cancer

OBJECTIVE: To evaluate the changing trends of standards and practices for postoperative radiotherapy (RT) for patients with prostate cancer in Japan. METHODS: The Japanese Patterns of Care Study (PCS) conducted a national survey in 84 institutions from 1996 to 1998 (PCS96-98) and 76 institutions from 1999 to 2001 (PCS99-01). Detailed information relevant to RT was collected on a total of 169 patients (64 from 1996 to 1998 and 105 from 1999 to 2001) with prostate cancer who had undergone radical prostatectomy. RESULTS: The fraction of clinical T3-4 tumours before prostatectomy decreased from 63% in the period 1996-98 to 26% in the period 1999-2001 (P = 0.0004). The pre-RT prostate-specific antigen level was significantly lower in 1999-2001 than in 1996-98 (P = 0.0002). We did not find a significant difference in the percentage of patients who received pelvic irradiation in the time periods between PCS96-98 and PCS99-01 (P = 0.18). Although the median radiation doses of 60 Gy were not changed between the surveys, various doses (from 20 to 74.6 Gy) were delivered to the prostatic bed. In the 1999-2001 survey, 73 of 105 patients received a median dose of 56 Gy in an adjuvant setting, while the other 32 received a median dose of 60 Gy in a salvage setting (P = 0.0015). CONCLUSION: These data suggest that consensus has not been reached on the practice and management of postoperative RT for patients with prostate cancer in Japan.     

Postoperative radiotherapy for non-small-cell lung cancer: results of the 1999-2001 patterns of care study nationwide process survey in Japan

To investigate the practice process of postoperative radiation therapy for non-small-cell lung cancer (NSCLC) in Japan. Between April 2002 and March 2004, the Patterns of Care Study conducted an extramural audit survey for 76 of 556 institutions using a stratified two-stage cluster sampling. Data on treatment process of 627 patients with NSCLC who received radiation therapy were collected. Ninety-nine (16%) patients received postoperative radiation therapy between 1999 and 2001 (median age, 65 years). Pathological stage was stage I in 8%, II in 17%, IIIA in 44%, and IIIB in 20%. The median field size was 9 cmx11 cm, and median total dose was 50 Gy. Photon energies of 6 MV or higher were used for 64 patients, whereas a cobalt-60 unit was used for five patients. Three-dimensional conformal treatment was used infrequently. Institutional stratification influenced several radiotherapy parameters such as photon energy and planning target volume. Smaller non-academic institutions provided worse quality of care. The study confirmed continuing variation in the practice of radiotherapy according to stratified institutions. Outdated equipment such as Cobalt-60 units was used, especially in non-academic institutions treating only a small number of patients per year.     

The evolving role of external beam radiotherapy in localized prostate cancer

Primary organ-confined prostate cancer is curable with external-beam radiotherapy. However, prostate cancer expresses a unique radiobiological phenotype, and its ablation requires doses at the high-end range of clinical radiotherapy. At this dose level, normal tissue radiosensitivity restricts the application of curative treatment, and mandates the use of the most advanced high-precision treatment delivery techniques to spare critical organs at risk. The efficacy and tolerance of dose-escalated conventional fractionated radiotherapy and of the biological equivalent doses of moderate and extreme hypofractionation are reviewed. Current studies indicate that novel risk-adapted techniques to spare normal organs at risk are still required to deploy high-biological equivalent dose extreme hypofractionation, while affording preservation of quality of life and cost-effectiveness.     

Patterns of radiotherapy practice for patients with cervical cancer (1999-2001): patterns of care study in Japan

PURPOSE: To describe the patterns of definitive radiotherapy practice for patients with uterine cervical cancer from 1999 to 2001 in Japan. METHODS AND MATERIALS: The Japanese Patterns of Care Study (JPCS) working group conducted a third extramural audit survey of 68 institutions and collected specific information on 324 cervical cancer patients treated with definitive radiotherapy. RESULTS: Almost all patients (96%) were treated with whole pelvic radiotherapy using opposing anteroposterior fields (87%). A midline block was used in 70% of the patients. Intracavitary brachytherapy (ICBT) was applied in 82% of cases. Most patients (89%) were treated with high-dose rate (HDR) ICBT. Calculation of doses to organs at risk (ICRU 38) was performed for rectum in 25% of cases and for bladder in 18% of cases. Only 3% of patients were given intravenous conscious sedation during ICBT applicator insertions. The median total biologically effective dose at point A (EBRT+ICBT) was 74 Gy(10) in cases treated with HDR-ICBT. There was no significant difference in total biologically effective dose between stages. The median overall treatment time was 47 days. Concurrent chemoradiation was applied in 17% of patients. CONCLUSIONS: This study describes the general patterns of radiotherapy practice for uterine cervical cancer in Japan. Although methods of external radiotherapy seemed to be appropriate, there was room for improvement in ICBT practice, such as pretreatment. A substantial difference in total radiotherapy dose between Japan and the United States was observed.     

1998-1999 patterns of care study process survey of national practice patterns using breast-conserving surgery and radiotherapy in the management of stage I-II breast cancer

PURPOSE: The Patterns of Care Study survey process evaluation has been an effective means of assessing the evaluation and treatment practices used by radiation oncologists in the United States for Stage I-II breast cancer. The current 1998-1999 report updates the previous 1989 and 1993-1994 analyses and reflects the recent changes in surgery and systemic therapy observed nationally in the management of early-stage disease. METHODS AND MATERIALS: A weighted sample size of 71,877 patient records of women treated with breast-conserving surgery and radiotherapy (RT) was obtained from a stratified two-stage sampling of 353 patient records. These cases were centrally reviewed from academic and private radiation oncology practices across the United States. The data collected included patient characteristics, clinical and pathologic factors, and surgical and RT details. The results were compared with those of previous Patterns of Care Study survey reports. RESULTS: Of the patients in the current survey, 97% had undergone mammography before biopsy. A review of the primary tumor pathologic findings indicated improved quantification of an intraductal component from 7.0% in 1993-1994 to 20.4% in 1998-1999 (p = 0.01). The tumor characteristics were better defined, with estrogen and progesterone receptor measurement performed in 91.4% and 91.3% in the 1998-1999 survey vs. 83.7% and 80.3% in the 1989 survey, respectively (p = 0.03 and p = 0.002, respectively). Axillary dissection was performed in 82.2% in the present survey compared with 93.6% in the 1993-1994 survey (p = 0.0004); sentinel node biopsy was performed in 20.1% of the present cases. The use of CT for planning was increased in the current survey, with 22.9% cases CT planned vs. 9% in 1993-1994 (p = 0.10). In the present survey, 100% had received whole breast RT. When a supraclavicular field was added, the dose was prescribed to a specified depth in 67.5% of cases, most commonly 3 cm. When an axillary field was added, the dose was generally prescribed to the mid-plane. Chemotherapy and tamoxifen was used in 36% and 55.8% of patients, respectively, in the 1998-1999 survey, representing a statistically significant increase compared with the 1993-1994 survey, despite comparable pathologic tumor size and nodal involvement. CONCLUSION: The present results demonstrate a high level of compliance of the sampled radiation oncology practices with current breast conservation standards and continued improvement in many categories compared with prior patterns of care study surveys. The estimates in the current survey after whole breast RT will serve as a benchmark against newer trends in breast cancer RT, such as partial breast RT.     

Postoperative radiotherapy for uterine cervical cancer: results of the 1995-1997 patterns of care process survey in Japan

OBJECTIVE: To determine the average national practice of postoperative radiotherapy for uterine cervical cancer in Japan. METHODS: The Japanese Patterns of Care Study (PCS) reviewed the process of care employed for 455 uterine cervical cancer patients who were treated with surgery followed by postoperative radiotherapy (RT) during 1995-1997. Cases with missing data were excluded from calculations of percentage and significance for each of the surveyed items. RESULTS: According to FIGO stages, 198 patients (45%) were in stage I, 52 patients (12%) were in stage IIA, 146 patients (33%) were in stage IIB and 46 patients (10%) were in stage III/IVA. The most common surgical procedure among the patients was radical hysterectomy (73%). Three hundred and seventy patients (82%) were treated with external beam RT (ERT) alone, and 74 patients (17%) were treated with a combination of ERT and intracavitary RT (ICRT). A midline block was used for the pelvic field in 63 patients (14%). Only seven patients (2%) were treated with extended field ERT. Pelvic ERT was most often performed using AP-PA opposed fields for 431 patients (97%). A majority of the patients (312 patients, 70%) were treated with a total dose of 45.0-50.4 Gy for ERT. Chemotherapy (CT) was administered to 178 patients (40%), neoadjuvant preoperative CT was administered to 80 patients (22%) and concurrent CT with postoperative RT was administered to 29 patients (8%). CONCLUSION: This PCS established the national practice average of postoperative RT for uterine cervical cancer. Follow-up studies need to be conducted to determine whether the observed differences in treatment processes affect outcomes.     

Complications of treatment with local field external beam radiotherapy for localized prostate cancer

We performed this analysis to document the rate and severity of complications both during and after local field irradiation for localized prostate cancer and to assess the influence of three-dimensional conformal radiation therapy (3DCRT) on these complications. Bowel, urinary and cutaneous toxicities were noted in all patients treated with primary radiotherapy (RT) for prostate cancer using Radiation Therapy Oncology Group/European Organization for Research on Treatment of Cancer scores. Evaluations were performed weekly during RT, 6 weeks after RT and 3 monthly thereafter. Data on 111 were analysed. We also compared the complications of conventional and 3DCRT. The serious complication rates identified in this study compare favourably with those reported in the literature. Only 3.6%, 0.8% and 0% had acute grade 3 or 4 urinary, bowel or skin reactions respectively. Only two patients had chronic grade 3 or 4 urinary complications. Thus far no patients have developed chronic bowel or skin complications greater than grade 2. Despite dose escalation from 66 Gy to 70 Gy (with 3DCRT), there was a trend towards reduced toxicity when 3DCRT was compared with conventional radiation. RT is a well-tolerated treatment for early stage carcinoma of the prostate and our complication rates are compatible with international experiences. Further follow-up is required to determine the efficacy of treatment, the incidence of impotence and the final number of late complications.     

Toxicity profile with a large prostate volume after external beam radiotherapy for localized prostate cancer

PURPOSE: To assess the impact of prostate volume on health-related quality of life (HRQOL) before and at different intervals after radiotherapy for prostate cancer. METHODS AND MATERIALS: A group of 204 patients was surveyed prospectively before (Time A), at the last day (Time B), 2 months after (Time C), and 16 months (median) after (Time D) radiotherapy, with a validated questionnaire (Expanded Prostate Cancer Index Composite). The group was divided into subgroups with a small (11-43 cm(3)) and a large (44-151 cm(3)) prostate volume. RESULTS: Patients with large prostates presented with lower urinary bother scores (median 79 vs. 89; p = 0.01) before treatment. Urinary function/bother scores for patients with large prostates decreased significantly compared to patients with small prostates due to irritative/obstructive symptoms only at Time B (pain with urination more than once daily in 48% vs. 18%; p < 0.01). Health-related quality of life did not differ significantly between both patient groups at Times C and D. In contrast to a large prostate, a small initial bladder volume (with associated higher dose-volume load) was predictive for lower urinary bother scores both in the acute and late phase; at Time B it predisposed for pollakiuria but not for pain. Patients with neoadjuvant hormonal therapy reached significantly lower HRQOL scores in several domains (affecting only incontinence in the urinary domain), despite a smaller prostate volume (34 cm(3) vs. 47 cm(3); p < 0.01). CONCLUSIONS: Patients with a large prostate volume have a great risk of irritative/obstructive symptoms (particularly dysuria) in the acute radiotherapy phase. These symptoms recover rapidly and do not influence long-term HRQOL.     

前列腺癌的外照射放疗进展

外照射放疗作为前列腺癌的主要治疗手段之一,随着放疗技术的进步、靶区认识的统一,已进入精确放疗时代.高剂量放疗的准确实施,使前列腺癌的疗效显著提高.而影像引导的放射治疗、质子放疗和低分割放疗则是疗效进一步提高的研究方向.     

Trends in the practice of radiotherapy for localized prostate cancer in Japan: a preliminary patterns of care study report

BACKGROUND: This is the first study to examine the characteristics and changes of the patterns of radiotherapy for prostate cancer in Japan. METHODS: The Japanese Patterns of Care Study (PCS) conducted a random survey of 84 institutions nationwide. Detailed information was collected on prostate cancer patients without distant metastases, who received radiotherapy during 1996-1998 and 1999-2001. RESULTS: The patients were divided into three groups: The Fresh Group (n = 338) was treated with radical radiotherapy with photon beams; the Surgery Group (n = 115) was treated after prostatectomy; and the Hormone-Refractory Group (n = 117) was treated after progression from hormonal therapy. In the Fresh Group, there was a decline in the fraction of patients with T3-4 tumors, from 65.2% in 1996-1998 to 43.9% in 1999-2001. In 1999-2001, a higher median dose of 69 Gy was irradiated as compared to 65 Gy in 1996-1998. In particular, the fraction of the patients treated with doses >or=70 Gy increased from 16.4% to 46.3%. In the Surgery Group, the percentage of clinical T3-4 tumors before prostatectomy decreased from 71.4% in 1996-1998 to 16.2% in 1999-2001. The median radiation dose of 60 Gy did not change, but the 1999-2001 results showed a decrease in the use of doses <60 Gy. In the Hormone-Refractory Group, the median dose increased from 60 Gy in 1996-1998 to 67 Gy in 1999-2001. CONCLUSION: These data suggest that radiation doses for prostate cancer in Japan have increased dramatically within a short period of time.     

Erectile function following external beam radiotherapy for clinically organ-confined or locally advanced prostate cancer

BACKGROUND: External beam radiotherapy (XRT) has been a standard treatment for clinically localized prostate cancer. However, preservation of erectile function following XRT is controversial. In this study, the influence of XRT on erectile function of patients with clinically organ-confined or locally advanced prostate cancer was retrospectively evaluated. METHODS: The study included 34 of 84 patients with organ-confined or locally advanced prostate cancer who underwent XRT between 1995 and 2002. Erectile function following radiotherapy was assessed by a simple mailed questionnaire that was constructed for the study. To determine the predictive factors for erectile dysfunction following radiotherapy, data were analyzed by multivariate analysis with the Cox proportional hazards model. RESULTS: The modality of XRT was the only factor to independently predict erectile dysfunction following XRT. The maintenance rates of erectile function were 47.6% at 1 year and 19% at 3 years in patients who received the 3-dimensional conformal radiotherapy, which were significantly higher than in those who received conventional radiotherapy (P = 0.026). CONCLUSIONS: XRT significantly reduced the maintenance rate of erectile function during the follow-up period, with the rate being 19% at 3 years in patients who received 3-dimensional conformal radiation. The XRT modality was involved in the reduction of erectile function. These results suggest that erectile dysfunction is a possible adverse event following XRT.