Patterns of care study: comparison of process of post-mastectomy radiotherapy (PMRT) in Japan and the USA.

BACKGROUND

The Patterns of Care Study (USPCS) by the American College of Radiology (ACR) has made significant contributions to improvements in the procedures of care for patients with breast cancer in the USA. The purpose of this study was to identify problems associated with the process of care for patients undergoing post-mastectomy radiotherapy (PMRT) in Japan compared with those in the USA.

METHODS

The Japanese Patterns of Care Study Subgroup (JPCS) conducted a national survey in 1998-2000, involving 79 institutions and using two-stage cluster sampling of institutions and patients, which showed that between 1995 and 1997 PMRT was performed on 258 patients. The survey of the USPCS, involving 55 institutions, found that 407 patients received PMRT between 1998 and 1999.

RESULTS

More than three axillary positive nodes were detected in 54% of the patients covered by the JPCS and in 46% of those covered by the USPCS. The clinical set-up of radiation treatment was planned without the aid of computed tomography or X-ray simulation for 25% of the JPCS patients and for 6% of the USPCS patients. The chest wall of 31% of the JPCS patients and of 98% of the USPCS patients was irradiated. The JPCS showed that inappropriate radiation techniques such as parallel opposed fields for chest wall irradiation were used for 3% of the patients in academic facilities, but for 25% of those in non-academic facilities (P = 0.0002).

CONCLUSION

There is ample room for improvement in radiation treatment planning and chest wall irradiation techniques in Japan.