Current status of therapy for breast cancer worldwide and in Japan

Abstract

The results of clinical trials conducted in Europe and North America have been incorporated into treatment strategies for breast cancer in Japan. Despite the use of similar treatment regimens, why has mortality from breast cancer been increasing in Japan? Procedures for surgical treatment and sentinel lymph node biopsy in breast cancer do not differ between Japan and Western countries, but the strategies for radiotherapy differ slightly. Hormonal therapy is now selected on the basis of scientific evidence, and similar regimens are used in Japan and Western countries. As for postoperative adjuvant chemotherapy, an anthracycline plus cyclophosphamide and taxane-based regimens are standard treatments in Japan and Western countries. In 2009, however, the results of two large clinical studies designed to determine whether intravenous or oral treatment was superior for postoperative adjuvant chemotherapy were reported in Japan. Both studies showed that relapsefree survival and overall survival (OS) at 5 years after surgery were similar for a combination of cyclophosphamide, methotrexate, and 5-fluorouracil and for tegafur/uracil. Many chemotherapeutic agents that are used to treat recurrent or metastatic breast cancer have not yet been approved in Japan. As for molecular targeted therapy, some agents that target the human epidermal growth factor receptor family have been approved in Japan, whereas angiogenesis inhibitors have not. The results of many clinical trials have been incorporated into clinical practice in Japan, therefore, the outcomes of breast cancer therapy have surpassed those in other countries. Many pivotal clinical trials have been conducted outside Japan. Treatment regimens that have been developed on the basis of these studies might be suitable for the management of breast cancer in Western women, but not for Japanese women because of differences in genetic factors, physique, body mass index, pharmacokinetics, and drug metabolism. Such regimens should be modified on the basis of the characteristics of breast cancer in Japan to develop treatment that is optimally suited for Japanese women. In particular, local studies of pharmacokinetics, pharmacodynamics, and optimal dose levels and treatment intervals should be carefully performed. The establishment of treatment regimens optimally suited for Japanese patients with breast cancer could put the brakes on the trend towards increasing mortality from breast cancer in Japan.

Management and Outcomes of Male Breast Cancer in Zaria, Nigeria

“…In the present study, all patients presented with axillary lymphadenopathy similar to other reports from our subregion [6, 9, 23]. This is higher than 37.7%–55% reported from high-income countries [14, 24]. It has been suggested that because breast tumors in men are usually superficial and centrally located, these tumors have a ready access to dermal lymphatics, pectoral fascia and subareolar lymphatic channels [5].…”

“…In our patients, the factors that significantly affect prognosis were stage of disease, axillary lymph node status, and use of chemotherapy. Tumor stage and axillary nodal status have consistently been shown to be the most important independent predictors of overall survival [ 24 , 33 ].…”

Factors influencing patient decision-making between simple mastectomy and surgical alternatives

“…Among women in Singapore who chose to have a mastectomy, only 18 per cent underwent reconstruction after mastectomy. This again differs from the West and other parts of Asia, where reported rates of reconstruction after mastectomy are approximately 60 per cent .…”

“…Indeed, BCT is the preferred locoregional treatment in most western countries, with reported rates ranging from 65 to 70 per cent . In parts of Asia, rates of BCT range between 60 and 65 per cent . In comparison, uptake of BCT in Singapore is much lower at 30–40 per cent.…”

Sentinel-Node-Driven Personalized Radiation Techniques Ranging from Partial Breast Irradiation to Regional Nodal Radiation after Breast-Conserving Surgery

“…After the introduction of a mammography program to screen for breast cancer, the ratio of patients who underwent BCS increased, and this procedure became the most common treatment for breast cancer after 2003 [31,32]. Breast-conserving therapy consisting of BCS with radiotherapy has become the standard of care for early-stage breast cancer because of equivalent local control and survival for both BCT and mastectomy.…”