Biomedical subjects
Tsunehiro Nishi
Publications and source records attributed to Tsunehiro Nishi.
Ipsilateral breast tumor recurrence (IBTR) after breast-conserving treatment for early breast cancer: risk factors and impact on distant metastases.
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.
1-hexylcarbamoyl-5-fluorouracil + cyclophosphamide + tamoxifen versus CMF + tamoxifen in women with lymph node-positive breast cancer after primary surgery: a randomized controlled trial.
We studied the usefulness of the oral 5-FU anti-cancer drug 1-hexylcarbamoyl-5-fluorouracil (HCFU) + cyclophosphamide (CPM) + tamoxifen (TAM) (HCT group) in comparison with CMF + TAM (CMFT group) in adjuvant therapy for breast cancer by a non-inferiority study based on a multi-institutional joint study. Clinical stage I, II primary breast cancers with histologically positive axillary lymph node metastasis were randomly assigned to the HCT group or the CMFT group after primary surgery. We registered 136 cases (HCT group 68 cases, CMFT group 68 cases). No significant difference in the 5-year overall survival rate (OS) and the 5-year disease-free survival rate (DFS) was found between the two groups. In the stratified analysis, DFS in cases in which the number of metastatic lymph nodes was 1-3 was significantly better in the HCT group (HCT group 84.3%, CMFT group 69.4%, log-rank test p=0.0496). No significant difference in the total incidence of adverse effects was found between the two groups, but there were significantly less adverse effects of grade 2 or over in the HCT group (p=0.034). The QOL survey at 3 months after surgery showed a significant decline of the QOL regarding lassitude, degree of difficulty in daily life, satisfaction with treatment and present mood in the CMFT group. Study results suggest that 2-year HCT therapy including the oral 5-FU anti-cancer drug HCFU is a useful adjuvant therapy which can replace CMFT therapy in early breast cancer cases with 3 or lower metastatic lymph nodes.
Long-term results of breast-conserving treatment for early-stage breast cancer in Japanese women from multicenter investigation.
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.