Influence of XRCC4 expression by breast cancer cells on ipsilateral recurrence after breast-conserving therapy.

BACKGROUND: We examined the expression of nonhomologous end-joining (NHEJ) proteins by breast cancer cells in patients with or without ipsilateral breast tumor recurrence (IBTR) after breast-conserving therapy. We also investigated whether there was a difference of NHEJ-related protein expression by tumor cells between two types of IBTR, i.e., true recurrence (TR) with regrowth from the tumor bed or development of a new primary tumor (NP). PATIENTS AND METHODS: The original cohort comprised 560 breast cancer patients who received breast-conserving therapy between February 1995 and March 2006, including 520 patients without IBTR and 40 patients with IBTR. Propensity score matching was employed to select 40 trios (120 patients) consisting of 1 patient with IBTR and 2 patients without IBTR. Immunohistochemical examination of proteins related to NHEJ was performed in surgical specimens. RESULTS: The 40 patients with IBTR included 22 patients who developed TR and 18 who had NP. The 15-year overall survival rate was 85.9% for patients with NP and 95.5% for those with TR, while it was 96.5% for patients without IBTR. Patients with high XRCC4 expression in tumor cells had significantly higher IBTR rates than those with low XRCC4 expression (P < 0.001). The frequency of TR was significantly higher in patients with high expression of XRCC4 than in those with low XRCC4 expression (p < 0.001). XRCC4 expression by tumor cells was not significantly related to development of NP. CONCLUSION: IBTR due to TR may be related to low radiosensitivity of tumor cells, possibly related to high XRCC4 expression.

[Breast cancer].

In Japan, the incidence rate of breast cancer is increasing every year so as to become the most common cancer among Japanese women. One of every 16 women is anticipated to eventually suffer from breast cancer. However, unlike the incidence rate, the mortality rate of breast cancer is low, and the 5-year survival rate is about 80%. Mammography screening has been shown to be effective, but the screening rate is still low(20-30%), compared to screening rates for other organs. To increase the screening rate, the Japanese government has introduced free breast cancer screening. To make the system for breast cancer screening more efficient, we should determine the risk factors for Japanese women, and conduct such screening at public expense.

The treatment outcome of patients undergoing breast-conserving therapy: the clinical role of postoperative radiotherapy.

BACKGROUND: Treatment outcome was evaluated in patients who underwent breast-conserving therapy and tangential irradiation. After verifying background factors including systemic therapy, the clinical efficacy of postoperative irradiation was investigated. METHOD: There were 708 study subjects, all of whom had early breast cancer treated between 1992 and 2002. The median follow-up period was 83 months. After breast-conserving surgery, in patients with negative surgical margins, only tangential irradiation at 48 Gy/24 fr was performed. In contrast, in those with positive surgical margins, 10 Gy of radiation boost to the tumor bed with electrons was administered after tangential irradiation with 50 Gy/25 fr. Treatment outcome was analyzed using the Kaplan-Meier method and Cox's proportional hazards regression model. RESULTS: The disease-free survival and no-recurrence rates within the ipsilateral breast after 5 years were 93.4 and 97.2%, respectively. Risk factors for recurrence within the ipsilateral breast included younger age of patient, the number of positive lymph nodes, and no endocrine therapy. However, the surgical margin was not a risk factor. Risk factors for relapse outwith the ipsilateral breast included younger age, the number of positive lymph nodes, and recurrence within the ipsilateral breast. CONCLUSIONS: From our analysis of 708 Japanese women who received breast-conserving therapy, which can be regarded as a standard method in Japan, the treatment outcome was compatible with previous reports from other countries.

Efficacy of doxifluridine combined with weekly paclitaxel therapy in the treatment of advanced or recurrent breast cancer: results of the JMTO BC01 phase II trial.

We conducted a phase II study to determine the availability and safety of combination chemotherapy with weekly paclitaxel and doxifluridine (a capecitabine metabolite) in the treatment of advanced or recurrent breast cancer. Patients were treated with a combination chemotherapy regimen: doxifluridine was orally administered at 800 mg/day for 14 days, followed by a 7-day washout period. Paclitaxel was given intravenously on days 1 and 8 at 80 mg/m2 for 1 h, followed by a 1-week washout period. This 3-week cycle of therapy was repeated as long as possible (at least eight cycles) until the progression of the tumor and drug-related adverse effects were no longer observed. From May 2003 to December 2005, 26 patients were enrolled in the study. The overall response rate was 53.8% (95% confidence interval, 33.4-73.4%). The clinical benefit rate, including long-term no change, was 65.4% (95% confidence interval, 44.3-82.8%). Time to progression and survival time were 297 and 1182 days, respectively, for the 26 enrolled patients. No severe toxicities were observed. Grade 3/4 leucopenia in three patients, neutropenia in five patients, increased serum creatinine in three patients, hypercalemia in one patient, hypocalcemia in one patient, nausea/vomiting in two patients, and diarrhea in one patient. The good response rate and long time to progression and overall survival time of this doxifluridine combined with weekly paclitaxel therapy indicate its potential as a first-line or second-line treatment for advanced or recurrent breast cancer patients.

Ten-year results of a randomized trial on adjuvant chemo-endocrine therapy with tamoxifen for stage II breast cancer.

BACKGROUND: A prospective randomized multi-center study was undertaken for 2 years and 3 months from November 1982, with the aim of examining the significance of using a combination of futraful (FT) and tamoxifen (TAM) for postoperative adjuvant therapy for stage II breast cancer after curative surgery. METHODS: Patients were divided into two groups and received one of the following treatment protocols: treatment A, intravenous administration of doxorubicin (DOX) 20 mg/body on the day of surgery and 10 mg/body the next day, followed by oral FT 600 mg/day for 2 years from the 14th day after surgery; treatment B, the same pattern of DOX administration followed by combined therapy with FT and TAM 20 mg/day for 2 years. The number of patients was 428 (treatment A 210 and treatment B 218), of whom 418 (97.7%) were followed for 10 years for analysis. RESULTS: Significantly higher 5- and 10-year overall survival (OS) rates were observed with treatment B compared with treatment A (p=0.0101 and 0.0219). Node-positive patients appeared to derive more benefit from TAM than node-negative patients. The difference in 10-year OS between treatment A and treatment B was more evident than that of the 5-year OS in patients with more than 4 positive nodes (p=0.0313 vs. 0.0479). No increase in adverse reactions was seen as a result of combining TAM with FT. CONCLUSION: The study results demonstrate that for stage II breast cancer concomitant administration of FT and TAM is superior to FT alone for postoperative adjuvant therapy, and administration of TAM for 2 years may contribute not only to 5-year survival rates but also to 10-year survival rates of node-positive patients.

Randomized controlled trial comparing oral doxifluridine plus oral cyclophosphamide with doxifluridine alone in women with node-positive breast cancer after primary surgery.

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.

Efficacy of UFT plus Tamoxifen for Estrogen-Receptor-Positive Breast Cancer and Tamoxifen plus UFT for Estrogen-Receptor-Negative Breast Cancer : Adjuvant Therapy after Administration of Mitomycin.

OBJECTIVE: We conducted a prospective multicentre, collaborative randomised study on postoperative adjuvant therapy in patients with stage II primary breast cancer to evaluate the effect of a combination of tegafur and uracil (UFT) on tamoxifen (TAM) plus mitomycin (MM) in patients with estrogen-receptor-positive [ER(+)] breast cancer and TAM on UFT + MM in patients with estrogen-receptor-negative [ER(-)] breast cancer. METHODS: MM (13 mg/m(2)) was intravenously administered on the day of surgery for all patients, after which patients with ER(+) were randomised to TAM 20 mg/day (treatment A) or TAM 20 mg/day and UFT 400 mg/day (treatment B). Patients who were ER(-) were randomly allocated UFT 400 mg/day (treatment C) or TAM 20 mg/day and UFT 400 mg/day (treatment D). TAM and UFT were administered orally for 2 years, starting on day 14 after surgery. ENDPOINTS: 5-year disease-free survival (5y DFS), 5-year overall survival (5y OS), and safety. RESULTS: The study commenced in November 1988 and the data cut-off was May 1997 after follow-up of the last patient for 5 years. A total of 765 patients with stage II breast cancer were enrolled. 436 patients with ER(+) [group A: 213, group B: 223] and 317 patients with ER(-) [group C: 162, group D: 155] breast cancer were eligible for this study. The rate of 5y DFS was 83.1% for group A and 90.7% for group B (p = 0.020). There was a significant difference in 5y DFS between the two groups among postmenopausal and positive lymph node metastases patients. The incidence of adverse reactions was 4% for group A and 18% for group B (p < 0.05). The rate of 5y DFS was 77.1% for group C and 85.5% for group D (p = 0.063). The rate of 5y OS was 84.7% for group C and 89.8% for group D (p = 0.216). The incidence of adverse reactions was 18% in group C and 11% in group D (p = 0.06). CONCLUSION: UFT in combination with TAM + MM showed higher efficacy than TAM + MM as a postoperative combination therapy for breast cancer in patients with ER(+) breast cancer. A trend was observed in favour of the addition of TAM to UFT + MM in postmenopausal and lymph node metastases-negative patients with ER(-) breast cancer.

[Assessment of post-administration body distribution of toremifene and tamoxifen, and their administration regimens].

Toremifene is an anti-estrogenic drug like tamoxifen. We assessed the body distributions after administration of toremifene and tamoxifen in order to evaluate their treatment regimens by measuring the concentrations in tissues. It is known that, after toremifene (TOR) or tamoxifen (TAM) is consecutively administered to breast cancer patients, TOR or TAM and their main active N-desmethyl-metabolites (TOR-1 or TAM-1) are detected in sera, tumor tissues, and lymph nodes. Accordingly, after we administered toremifene or tamoxifen to primary breast cancer patients previous to surgery, we measured the concentrations of TOR, TOR-1, TAM, TAM-1 in sera, tumor tissues, and lymph nodes. We found that the concentrations of TOR and TOR-1 in sera, tumors, and lymph nodes reached a peak about 2 weeks after administration of toremifene 40 mg. Likewise, the concentrations of TAM and TAM-1 in sera, tumors, and lymph nodes reached a peak about 2 weeks after administration of tamoxifen, although the peak levels were lower than those of TOR or TOR-1. The concentrations of TAM-1 in lymph nodes were significantly and positively correlated to the duration of administration of TAM, and it was predicted that the concentration of TAM-1 in lymph nodes would reach a steady state at more than 4 weeks after administration of tamoxifen. The concentrations of TOR and TOR-1 were higher in tumors and lymph nodes than in sera. Furthermore, the concentrations of TOR and TOR-1 were significantly higher than those of TAM and TAM-1 in sera and tumors, respectively. Moreover, the concentration in tissue increased in a dose-dependent manner with administration of toremifene 120 mg. There were no significant differences between breast cancers positive and negative for estrogen receptors, with regard to the concentrations of TOR and TOR-1 in either sera, tumors, or lymph nodes. In conclusion, it would be expected that treatment with toremifene might be more effective for breast cancer than that with tamoxifen.

The effect of adjuvant 5'-deoxy-5-fluorouridine in early stage breast cancer patients: results from a multicenter randomized controlled trial.

To assess the efficacy of 5'-DFUR, an intermediate of capecitabine, for adjuvant treatment of early breast cancer, we conducted an open-labeled multi-center randomized controlled trial to compare postoperative 5'-DFUR treatment with surgery alone. We enrolled 1217 primary breast cancer patients and randomly assigned them into two treatment groups; one received six-month postoperative 5'-DFUR treatment by consecutive or intermittent administration, and the other surgery alone. Follow-up surveys were conducted once a year for all subjects simultaneously and examined their outcome/presence or absence of the cancer recurrence. The central study committee reviewed all follow-up data and judged the recurrence data to be used for the analysis. Eight-year follow-up data showed no significant differences in relapse-free and overall survival between the two groups, and 5'-DFUR treatment regimen showed an extremely high tolerance. Possible explanations are discussed for the finding of no significant survival difference between adjuvant 6-month 5'-DFUR monotherapy and surgery alone in early breast cancer.