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The prevalence of BRCA1/2 germline mutations in Japanese patients suspected to have hereditary breast/ovarian cancer was examined by a multi-institutional study, aiming at the clinical application of total sequencing analysis and validation of assay sensitivity in Japanese people using a cross-sectional approach based on genetic factors estimated from personal and family histories. One hundred and thirty-five subjects were referred to the genetic counseling clinics and enrolled in the study. Full sequencing analysis of the BRCA1/2 gene showed 28 types of deleterious mutations in 36 subjects (26.7%), including 13 types of BRCA1 mutations in 17 subjects (12.6%) and 15 types of BRCA2 mutations in 19 subjects (14.1%). Subjects were classified into five groups and 22 subgroups according to their personal and family history of breast and/or ovarian cancer, and the prevalence of deleterious mutations was compared with previously reported data in non-Ashkenazi individuals. Statistical analysis using the Mantel-Haenszel test for groups I through IV revealed that the prevalence of Japanese subjects was significantly higher than that of non-Ashkenazi individuals (P = 0.005, odds ratio 1.87, 95% confidence interval 1.22-2.88). Family history of the probands suffering from breast cancer indicated risk factors for the presence of deleterious mutations of BRCA1/2 as follows: (1) families with breast cancer before age 40 within second degree relatives (P = 0.0265, odds ratio 2.833, 95% confidence interval 1.165-7.136) and (2) families with bilateral breast cancer and/or ovarian cancer within second degree relatives (P = 0.0151, odds ratio 2.88, 95% confidence interval 1.25-6.64).

Background: The clinical features of ipsilateral breast tumor recurrence (IBTR) after breast conserving therapy (BCT) for early stage breast cancer were analyzed from long-term follow-up of BCT in Japan. The purpose of this study was to clarify risk factors of IBTR and the impact of IBTR on development of distant metastases in this ethnic group., Methods: Patients (N = 1901)with unilateral breast cancer < or = 3 cm in diameter who underwent BCT at 18 Japanese major breast cancer treatment institutes from 1986 to 1993 were registered in this study. Survival rates, the incidences of IBTR and distant metastases, and annual rates of IBTR and distant metastases after primary operation were calculated by the Kaplan-Meier method. A Cox proportional hazards model was used to estimate the risks of IBTR and distant metastases. A Cox model was also used to estimate the risks of distant metastases after IBTR in the group of IBTR., Results: At a median follow-up time of 107 months, the 10-year overall and disease-free survival rates were 83.9% and 77.8%, respectively. The 10-year cumulative rates of IBTR were 8.5% in the patients with postoperative irradiation and 17.2% in the patients without irradiation. The 10-year cumulative distant metastasis rate was 10.9%. On multivariate analysis, young age, positive surgical margin, and omission of radiation therapy were significant predictors of IBTR. In addition, IBTR significantly correlated with subsequent distant metastases (hazard ratio, 3.93; 95% confidence interval, 2.676-5.771; P < 0.0001). Among patients who developed IBTR, initial lymph node metastases and short interval to IBTR were significant risk factors for subsequent distant metastasis., Conclusions: Young age, positive surgical margin, and omission of radiation therapy seemed to be important factors in relation to local control. The authors' results also indicated that IBTR is significantly associated with subsequent distant metastasis. Patients with positive nodal status at primary operation or with short interval from primary operation to IBTR are at especially high risk of distant metastasis. It remains unclear, however, whether IBTR is an indicator or a cause of subsequent distant metastases., (Copyright 2005 American Cancer Society.)

Background: Ipsilateral breast tumor recurrences (IBTR) after breast-conserving treatment include two different entities: true recurrence (TR) thought to occur when residual cancer cells grow gradually to detectable size and new primary (NP) thought to be de novo cancer independently arising in the preserved breast. The patients with ipsilateral breast tumor recurrence (IBTR) are potentially at high risk for subsequent distant metastasis, but many studies do not distinguish between these types of recurrence. The aim of this study is to clarify the biological difference between TR and NP, and to show the clinical significance of classifying IBTR into these two types of recurrence., Patients and Methods: A total of 172 patients with IBTR after breast-conserving therapy from the cohort of a long-term large scale study (Research of cancer treatment from the Ministry of Health, Labor and Welfare of Japan (no.13-9)) were analyzed. We classified IBTRs as TR or NP based on tumor location and pathological findings. The characteristics of the primary tumors of TR and NP were compared. Survival rates and risk factors of each type of IBTR were examined by the Kaplan-Meier method. The results of salvage surgery were also analyzed., Results: Of the 172 patients, 135 patients were classified as TR and 26 as NP. Eleven cases could not be categorized. The primary tumor of TR was characterized by a high rate of lymph node metastasis (37.8%) and short disease-free interval (mean DFI; 46.6 months) while that of NP showed a rather low lymph node positivity (8.7%) and longer DFI (62.1 months). The risk factors for TR were young age, positive surgical margin, omission of irradiation and positive lymph node metastasis. Those for NP were young age, omission of irradiation and contralateral breast cancer after the primary operation. The 5-year survival rates after IBTR were 71.0% in TR and 94.7% in NP (p=0.022). Salvage operation was performed in 136 IBTRs. Eighty-one patients underwent salvage mastectomy and 55 patients underwent repeat lumpectomy. Five-year survival rates after salvage operation were 75.7% for mastectomy and 84.2% for lumpectomy (N.S.). Twenty percent of patients who underwent repeat lumpectomy developed secondary local relapse within 5 years after salvage treatment. The risk factors for secondary local relapse were analyzed. Limited to cases of IBTR which received radiation therapy after the primary operation, NP was the only factor influencing secondary local relapse by univariate analysis., Conclusions: TR and NP show clinically quite different features; time to occurrence, characteristics of the original tumor, prognosis and risk factor profile for IBTR were all different. Classifying IBTR as TR or NP can provide clinically significant data for the management of IBTR.

The number of breast cancer cases undergoing sentinel lymph node biopsy (SLNB) has been increasing with the number of articles published in Japan. SLNB using the dye method alone is performed in about one-third of patients. Analysis of questionnaire responses from 40 institutions in Japan revealed an identification rate by the dye method alone of 87%, compared with 96% using the combined method; the combined method is now recognized in Japan as superior to the dye method alone. No dyes have been specifically approved by the government for use in SLNB, and physicians have been using several inappropriate dyes as tracers for SLNB, such as indocyanine green, patent blue, indigo carmine, and isosulfan blue. The colloidal radiotracers used in Japan include tin colloid, stannous phytate, rhenium sulfate and human serum albumin. Albumin colloid and sulfur colloid are not commercially available in Japan. Small-size tin colloids, stannous phytate and rhenium sulfate all yield good results in terms of detection and false-negative rates. Provided that the surgeon has adequate experience in SLNB, a negative sentinel node can serve as a substitute for negative results from axillary lymph node dissection. Although many institutions have introduced SLNB, few reports have focused on the results of SLNB without axillary dissection because of short follow-up times and small number of patients. The final decision as to whether SLNB is an adequate substitute for axillary dissection awaits the results of prospective randomized trials.

Sentinel node adenectomy has rapidly been accepted in recent years. A survey performed under the auspices of the Japanese Breast Cancer Society revealed that about 40% of institutions in Japan have already introduced sentinel lymph adenectomy. Analysis of questionnaire responses from 40 institutions in Japan revealed an identification rate using the dye method alone of 87% compared with 96% using the combined method. The identification rate and the false-negative rate are about the same among various methods used such as colloidal radiotracers, injection site, use of lymphoscintigraphy, etc., provided that the surgeon has adequate experience. It is recommended that the surgeon should start to perform sentinel node adenectomy after experiencing more than 60 cases, because there is a learning curve. Some investigators are devising other methods to replace the RI method, for example, using magnetic particles instead of RI colloid and detecting them using magnetic probes. and a trial to detect lymphatic flow with CT after local injection of contrast medium is also being conducted. Sentinel node adenectomy may become a standard technique for early breast cancer patients in the near future.

Based on reviews of the Japanese clinical trial situation in lung cancer, gastric cancer, prostate cancer and breast cancer, it was clear that much progress has been made in short time. There are considerable differences between Japan and the West and also differences between clinical areas in Japan. For regulatory purposes bridging studies have become increasingly important. Use of identical protocols are required for effective bridging. Participations in global phase III trials is the best way of achieving registration in Japan. For successful global trials in Japan it is important to include Japanese investigators in the preparation of the protocol and to recognise the challenges facing such a project. Clinical practice in diagnosis and treatment have many differences, thus it is recommended to have clear and detailed information in the protocol. Hard end points like survival are important since they are not biased by cultural differences. There are clear difficulties with HE or QOL outcomes. The emergence of focus on evidence based medicine is also happening in Japan and will help to harmonize documentation across the world. For large adjuvant or prevention cancer global trials are essential. To facilitate global studies further development of infrastructure is necessary in Japan. Use of electronic data capture web based communication etc. will help overcome communication difficulties. Other improvements that will make Japanese participation in global trials easier and better include establishment of clinical trial centre at each hospital, introduction of trial coordinators or study nurses and an improved collaboration with company staff. A critical issue that also need addressing is agreement of centre target recruitment. We need to introduce a new flexible system in Japan if participation in global trial is to be optimised. If we can address these issues Japanese investigators and collaborative groups should be able to initiate and lead global trials in the future.

Purpose: We compared the therapeutic usefulness of doxifluridine (5'-DFUR) alone and a combination of 5'-DFUR plus cyclophosphamide (CPM), both of which are considered effective against advanced and recurrent breast cancer, to determine which treatment is more beneficial as postoperative adjuvant chemotherapy., Patients and Methods: A total of 1,131 women with node-positive primary breast cancer were randomly assigned after primary surgery to receive 5'-DFUR alone or 5'-DFUR plus CPM. All patients initially received 5'-DFUR in an oral dose of 1,200 mg/d for 4 weeks, starting 4 weeks after surgery. Chemotherapy was then not given for 2 weeks. Patients in the 5'-DFUR group subsequently received five 4-week cycles of treatment consisting of oral 5'-DFUR (1,200 mg/d) for the first 2 weeks and no chemotherapy for the next 2 weeks. Those assigned to the 5'-DFUR plus CPM group also received oral CPM 100 mg/d for the first 2 weeks and no chemotherapy for the next 2 weeks. Women 50 years or older concurrently received 20 mg/d of tamoxifen for 2 years in both groups., Results: Of the 1,088 eligible women, 546 were assigned to receive 5'-DFUR alone and 542 were assigned to receive 5'-DFUR plus CPM. Overall disease-free survival was significantly better in women who received 5'-DFUR plus CPM than in those who received 5'-DFUR alone (log-rank test, P =.021). Toxic effects occurred in 20.0% of patients (109 of 546) in the 5'-DFUR group and 32.3% of patients (175 of 542) in the 5'-DFUR plus CPM group (chi(2) test, P <.001)., Conclusion: Combination therapy with 5'-DFUR plus CPM is more effective in preventing recurrence than 5'-DFUR alone.

Background: Although many clinical data regarding breast-conserving treatment have already been reported from European and North American countries, few clinical data with long-term follow-up have been reported from Japan., Method: We collected information on therapeutic and possible or developed prognostic factors and follow-up data for Japanese women who had received breast-conserving treatment consisting of wide excision of the primary tumor, axillary dissection and radiotherapy for unilateral breast cancer considered suitable for breast-conserving treatment from 18 Japanese major breast cancer treating hospitals; 1561 patients were registered., Results: The median follow-up period was 77 months. Five-year disease-free and overall survival rates were 89.4 and 95.9%, respectively. The 5-year local recurrence-free rate was 96.3%. The patients with histologically positive margins (P < 0.0001) or estrogen receptor negative tumor (P = 0.0340) or younger than 40 years old (P < 0.0001) developed statistically significantly more local recurrences. Adjuvant endocrine therapy was essential for the estrogen receptor positive patients to have a lower local recurrence rate. Endocrine therapy did not change the local recurrence rate among estrogen receptor negative patients at all. Multivariate analysis showed histological margin status and the combination of estrogen receptor status and endocrine therapy were independent prognostic factors for local recurrence., Conclusion: The 5-year local recurrence rate of Japanese breast cancer patients who were treated with breast-conserving treatment using radiotherapy was 3.7%. Independent prognostic factors for local recurrence were histological margin status and the combination of estrogen receptor status and adjuvant endocrine therapy.

Evidence Based Medicine (EBM) is a growing concept in Japan as it is elsewhere. Central to improving the use of EBM is generation of data through well conducted controlled clinical studies. There are many problems associated with conduct of clinical studies after launch in Japan, and many initiatives are ongoing to improve the situation. Development of Clinical Research Coordinators (CRO) and central Data Management centers are key to improving the quality of clinical research in Japan. Currently Japan has an undeveloped legal system with regard to post-launch trials and off-label use of registered drugs. There is no reimbursement for off-label and various restrictions imposed on the recipients of the Ministry of Health, Labour and Welfare's (MHLW) funds. Maybe the biggest problem is the high cost of post-marketing studies sponsored by pharmaceutical manufacturers. A high quality system to support post launch clinical studies need a solid financial base. There is a need for a suitable review system for investigator initiated multi-centre studies, as the current IRB system is not sufficient. There are also challenges regarding the differences, perceived or real, in treatment practice and available registrations in Japan and in the West, causing problems in choosing suitable comparators and study designs. At the present time it is not clear whether investigator initiated trials will be acceptable for registration purposes in Japan. The agreed first priority is to build a suitable and strong infrastructure within the academic community to support researchers to investigate important questions with or without pharmaceutical company support. Despite all these issues, several groundbreaking projects are under way throughout Japan, in many different areas and by different collaborative groups, some with government support. In fact, researcher-initiated clinical trials achieved a rapid growth in Japan in the past year.

Breast conserving operations have become the standard operation for early breast cancer. They were performed in about 40% of all breast cancer patients in Japan in 2000, and the percentage is still increasing. Ductal carcinoma in situ (DCIS) accounts for about 7% of all breast cancers and breast conserving operations for DCIS have been followed by a low in-breast recurrence rate, leading to wider indications for breast conserving operations as screening mammography has come to be used in Japan. In-breast recurrence is correlated to surgical margin status. It is important to evaluate the surgical margin for volume of cancer cell nests as well as for positivity. Neoadjuvant chemotherapy has become popular as an in vivo sensitivity test and as a means of down-staging to increase the possibility of performing a breast conserving operation. There are two patterns of shrinkage when neoadjuvant chemotherapy is effective: cocentric and honeycomb, and the pattern of residual cancer cell nests must be determined before surgery. MRI is an effective method of evaluating residual cancer cell nests. The in-breast recurrence rate after down-staging to perform breast conserving operations is reported to be higher than among candidates for breast conserving operation at the start. Sentinel node biopsy techniques and endoscopic operations are now being assessed in conjunction with breast conserving operations. The current status of breast conserving operations in Japan is reviewed in comparison with their status in Western countries.