SEARCH

SEARCH BY CITATION

Abstract

  1. Top of page
  2. Abstract
  3. Materials and Methods
  4. Results
  5. Discussion
  6. Acknowledgments
  7. Disclosure Statement
  8. References

Permanent implant brachytherapy for prostate cancer using iodine-125 seeds was adopted in Japan in 2003. Here, we report on the diffusion pattern of this treatment in Japan since 2003. We examined the annual numbers of prostate cancer patients per hospital in Japan, who were treated with iodine-125 seed implant brachytherapy with or without external beam radiation therapy between 2003 and 2011. The hospitals were excluded from the count if brachytherapy was begun in a hospital within the given year, and thus was only available for part of the year. In 2004, 269 patients were treated by brachytherapy at only two hospitals. However, the numbers increased rapidly. A total of 1412 patients were treated at 23 hospitals in 2005, 2783 patients were treated at 83 hospitals in 2008, and 3793 patients were treated at 109 hospitals in 2011. The mean/median numbers of patients treated per hospital were 61.4/42 in 2005, 33.5/25 in 2008, and 35.0/24 in 2011. The number of hospitals where 24 or fewer patients were treated in a year increased. On the other hand, the number of hospitals with a volume of >48 patients per year was stable. Because a relationship between provider volume and outcomes following oncological procedures was shown, a careful evaluation of the effectiveness of permanent implant brachytherapy for prostate cancer is needed.

When a medical technology, the usefulness of which has been established, is adopted in a country, how does the technology diffuse into medical practice? The speed and degrees of the diffusion depend upon many factors: consumer demand, promotional efforts of technology manufacturers, medical education, health insurance and payment systems, and governmental regulatory policies.[1]

Permanent implant brachytherapy for prostate cancer using iodine-125 (I-125) seeds was adopted in Japan in 2003.[2] The advantages of brachytherapy had been well recognized,[3] and the expectation for treatment was very high among Japanese urologists and radiation oncologists. In addition, the Cancer Control Act was approved in June 2006. Based on this law, the Basic Plan to Promote Cancer Control Programs was approved. One of its basic concepts is the equalization of cancer medical services including radiation therapy. This basic plan has stimulated the installation of new radiation therapy equipment at core hospitals.

In this study, we report on the diffusion pattern of permanent implant brachytherapy for prostate cancer in Japan since 2003, focusing in particular on the changes in the annual numbers of patients treated by brachytherapy per hospital since 2003.

Materials and Methods

  1. Top of page
  2. Abstract
  3. Materials and Methods
  4. Results
  5. Discussion
  6. Acknowledgments
  7. Disclosure Statement
  8. References

We examined the annual numbers of prostate cancer patients per hospital in Japan, who were treated with I-125 seed implant brachytherapy with or without external beam radiation therapy. The use of palladium-103 (Pd-103) seeds, which is common in the United States, is not permitted in Japan. To elucidate the actual number of patients treated in a year, the hospitals were excluded from the count if brachytherapy was begun in a hospital within the given year, and thus was only available for part of the year. Because brachytherapy using I-125 seeds was adopted in Japan in 2003, the annual numbers of patients treated with brachytherapy between 2004 and 2011 were examined. These data were estimated from the database by Japanese Prostate Permanent Seed Implantation Study Group.[4] In Japan, I-125 seeds are supplied from two radiation source supply companies to medical institutions via the Japan Radioisotope Association (JRIA). Their database was also used to confirm the estimation.

Results

  1. Top of page
  2. Abstract
  3. Materials and Methods
  4. Results
  5. Discussion
  6. Acknowledgments
  7. Disclosure Statement
  8. References

The total estimated number of patients treated with brachytherapy at hospitals where more than 1 year had passed since brachytherapy was first made available is shown in Table 1. In 2004, 269 patients were treated by brachytherapy only in two hospitals. However, the numbers increased rapidly. A total of 1412 patients were treated at 23 hospitals in 2005, 2783 patients were treated at 83 hospitals in 2008, and 3793 patients were treated at 109 hospitals in 2011.

Table 1. Total number of hospitals/patients and the breakdown of hospitals according to the number of patients per year, among hospitals where more than 1 year has passed since brachytherapy was first made available
 20042005200620072008200920102011
Total number of hospitals22338608394102109
Estimated total number of patients2691412179525162783311234423793
Percentage of hospitals
>96 patients/year50.017.47.95.04.87.46.96.4
48–96 patients/year50.030.428.923.310.810.611.811.9
24–48 patients/year0.034.836.835.036.131.924.526.6
12–24 patients/year0.017.410.518.332.528.735.333.9
≤12 patients/year0.00.015.818.315.721.321.621.1

Figure 1 shows the number of patients treated per hospital in 2005, 2008, and 2011. The mean/median number of patients treated per hospital was 61.4/42 in 2005, 33.5/25 in 2008, and 35.0/24 in 2011. Almost half of the patients in Japan were treated at the top six hospitals in 2005, at the top 18 hospitals in 2008, and at the top 22 hospitals in 2011. The number of hospitals in which 24 or fewer patients were treated in a year (i.e., two patients per month) was four in 2005, 40 in 2008, and 60 in 2011.

image

Figure 1. The annual number of patients treated with brachytherapy per hospital in hospitals where more than 1 year had passed since brachytherapy was first made available, in 2005, 2008, and 2011.

Download figure to PowerPoint

Figure 2 shows the distribution of the annual number of patients treated with brachytherapy per hospital from 2004 to 2011. The percentage of hospitals is also shown according to the number of patients per year in Table 1. The number of hospitals where 24 or fewer patients were treated in a year increased rapidly, in particular after 2006. On the other hand, the number of hospitals with a volume of >48 patients per year was stable.

image

Figure 2. Distribution of the annual number of patients treated with brachytherapy per hospital from 2004 to 2011.

Download figure to PowerPoint

Discussion

  1. Top of page
  2. Abstract
  3. Materials and Methods
  4. Results
  5. Discussion
  6. Acknowledgments
  7. Disclosure Statement
  8. References

Although the advantages of brachytherapy were well recognized among Japanese urologists and radiation oncologists, low dose rate brachytherapy for prostate cancer using I-125 or Pd-103 seeds had not been allowed in Japan, because of the strict Japanese laws on radiation safety.[2] However, after long discussions between members of the Japanese Society for Therapeutic Radiology and Oncology (JASTRO), the Japanese Urological Association (JUA), the Ministry of Health, Labor, and Welfare, and the Ministry of Education and Science, permanent implant brachytherapy for prostate cancer using I-125 seeds was approved in July 2003.[2] Even after permanent implant brachytherapy was permitted in Japan, only a limited number of institutions started the treatment, in part because of the very low price fixed by the Japanese health insurance system.[2] However, after a higher price for brachytherapy was approved by the Japanese health insurance system in April 2006, many institutes started providing the treatment, as shown in Figures 1 and 2. In particular, the number of hospitals with a low volume of patients increased.

Oncological procedures may have better outcomes if performed by high-volume providers. Killeen et al.[5] revealed that high-volume providers have significantly better outcomes for complex cancer surgery, in particular for pancreatectomy, esphagectomy, gastrectomy and rectal resection. In Japan, influences of hospital procedure volume on cancer survival have been under intense investigation using The Osaka Cancer Registry's data.[6-10] As for localized prostate cancer, Jeldres et al.[11] examined the effect of annual and cumulative provider volume on the rate of use of secondary therapies using a cohort of 3907 patients treated with definitive external-beam radiation therapy. They demonstrated lower rates of secondary therapy for providers with an annual provider volume >10 cases and for those with a cumulative provider volume >200 cases. Taussky et al.[12] showed that seed migration in prostate brachytherapy depended on experience and technique. Chen et al.[13] concluded that patients treated with brachytherapy by higher-volume physicians were at lower risk for recurrence and prostate cancer death. Interestingly, they showed that there was no significant association between hospital volume and recurrence, prostate cancer death or all deaths.

Japanese urologists and radiation oncologists have made a great effort to maintain the safety and quality of permanent implant brachytherapy for prostate cancer. JASTRO, JUA, and the Japan Radiological Society (JRS) have published guidelines for brachytherapy (in Japanese).[2, 14] These guidelines require physicians involved in this treatment to attend an education course held by JRIA. The guidelines also strongly recommend that each institution administering this treatment should have a urologist certified by the JUA and a radiation oncologist certified by JASTRO and/or JRS in full-time employment.[2] In addition, training workshops have been held at regular intervals to maintain or improve the technical level of permanent implant brachytherapy for prostate cancer. It is not still clear whether the provider volume is associated with outcomes following brachytherapy for prostate cancer in Japan.

The diffusion of a new medical technique depends upon many factors including consumer demand and health insurance and payment systems.[1] In Japan, although health care is under the management of an obligatory insurance system, it is within the framework of a capitalist economy.[15] Given this situation, a new “Basic Plan to Promote Cancer Control Programs” was approved in 2012. In addition to the further promotion of radiation therapy and the training of doctors/staff members specializing in this area, the plan recommends the centralization of high-precision radiation therapy including intensity-modulated radiation therapy (IMRT) in each medical region.

There are several new options for patients with clinically localized prostate cancer including robotic surgery, brachytherapy, and IMRT. The majority of the published papers have shown similar treatment results in large-scale institutions. However, after the diffusion of a new medical technique, evaluation of the quality remains an important issue. Therefore, a nationwide multi-institutional cohort survey for prostate brachytherapy focusing on the effect of provider volume on treatment efficacy and safety is needed.

Acknowledgments

  1. Top of page
  2. Abstract
  3. Materials and Methods
  4. Results
  5. Discussion
  6. Acknowledgments
  7. Disclosure Statement
  8. References

This study was supported in part by a Health Labor Sciences Research Grant (H23-Sanjigan-Ippan-007) from the Japanese Ministry of Health, Labor and Welfare.

References

  1. Top of page
  2. Abstract
  3. Materials and Methods
  4. Results
  5. Discussion
  6. Acknowledgments
  7. Disclosure Statement
  8. References