The effect of denosumab in breast cancer patients receiving adjuvant aromatase inhibitors: 36-month results.

INTRODUCTION: Aromatase inhibitor (AI)-associated bone loss increases the risk of bone fracture and reduces patients' quality of life, making it a critical issue worldwide. We conducted a prospective non-randomized clinical trial (UMIN-CTR, UMIN 000016173) to assess the effect of denosumab on bone loss in patients treated with adjuvant AI and have previously reported the results at 12 and 24 months. This study aimed to present the results at 36 months of treatment with denosumab for osteopenia in breast cancer patients who were undergoing treatment with adjuvant AI; 36 months is the longest denosumab treatment period reported so far. MATERIALS AND METHODS: Patients received 60-mg denosumab subcutaneously every 6 months. Daily supplements containing 500-mg elemental calcium and at least 400 international units of vitamin D were highly recommended throughout the study period. The levels of bone mineral density (BMD) and bone turnover markers, serum tartrate-resistant acid phosphatase isoform 5b, and bone alkaline phosphatase were determined at baseline and 6, 12, 18, 24, and 36 months. RESULTS: At 36 months, the bone mineral density of the lumbar spine, right femoral neck, and left femoral neck were found to increase by 8.8% (95% confidence interval CI 7.6-10.1), 4.3% (95% CI 3.0-5.5), and 3.1% (95% CI 2.1-4.1), respectively. No non-traumatic clinical fractures occurred in patients receiving AI and denosumab. CONCLUSION: Twice-yearly administration of denosumab to the breast cancer patients treated with adjuvant AI, regardless of the skeletal site, resulted in consistent increases in BMD without severe adverse events at 36 months.

Efficacy of denosumab for restoring normal bone mineral density in women receiving adjuvant aromatase inhibitors for early breast cancer.

BACKGROUND: Osteoporosis is a major side effect of aromatase inhibitors (AIs), which are greatly effective in the treatment of breast cancer. However, there are no satisfactory measures against osteoporosis. In this multicenter, randomized, comparative study, we evaluate the efficacy of denosumab for preventing loss of bone mineral density (BMD) induced by adjuvant therapy with AI s in breast cancer patients with normal BMD. PATIENTS AND METHODS: The bone loss-suppressing effect of denosumab will be comparatively evaluated in postmenopausal patients scheduled to receive letrozole or anastrozole as a postoperative endocrine therapy for stage I-IIIA hormone-sensitive breast cancer and a control group. Patients will be administered letrozole 2.5 mg or anastrozole 1 mg once a day, and the treatment will be continued for 5 years unless recurrence, secondary cancer, or unacceptable toxicity develops. Patients in the denosumab group will receive a subcutaneous injection of 60 mg of denosumab every 6 months. The primary endpoint is the rate of change in the lumbar spine (L1-L4) BMD, as determined by dual-energy X-ray absorptiometry (DXA), 12 months after the start of the injection. The secondary endpoints were ETHICS AND DISSEMINATION:: The protocol was approved by the institutional review boards of Kyoto Prefectural University of Medicine and all the participating faculties. Written informed consent was obtained from all patients before registration, in accordance with the Declaration of Helsinki. Results of the study will be disseminated via publications in peer-reviewed journals. TRIAL REGISTRATION: Clinical Trials.gov Identifier: NCT03324932, Japan Registry of Clinical Trial (jRCT): CRB5180001.

Predictive factors for the efficacy of denosumab in postmenopausal Japanese women with non-metastatic breast cancer receiving adjuvant aromatase inhibitors: a combined analysis of two prospective clinical trials.

Aromatase inhibitors (AIs) are the gold standard therapy for breast cancer in postmenopausal women. AI suppresses the conversion of androgens to estrogens; however, this results in osteopenia, osteoporosis, and bone fracture, thus reducing the patient's quality of life. The use of adjuvant denosumab reduces the risk of clinical fractures in postmenopausal patients with breast cancer receiving AI. However, the efficacy of denosumab in the treatment of AI-associated bone loss has not been prospectively evaluated in Japan. In this study, we aimed to investigate the predictive factors for the efficacy of denosumab in postmenopausal patients with breast cancer treated with AI by analyzing the results of two prospective trials. The patients received 60 mg denosumab subcutaneously every 6 months. The primary endpoint was percentage change in lumbar spine bone mineral density (BMD) from baseline to month 12 in lumbar spine. Post hoc analysis and T tests were performed. A total of 205 patients were enrolled. At 12 and 24 months, the lumbar spine BMD increased by 5.6% [95% confidence interval (CI) 4.9-6.3] and 8.3% (95% CI 7.5-9.1), respectively. Subgroup analysis was conducted according to the time of AI therapy initiation, type of AI therapy, age, time since menopause, baseline body mass index, and BMD. The results showed that baseline lumbar and left femoral BMD was significantly associated with a percentage change in these sites, respectively. In addition, baseline left femoral BMD was also associated with a change in lumbar BMD. In conclusion, the baseline BMD in the lumbar spine was a predictive indicator for the efficacy of denosumab in this site and the baseline BMD in left femoral neck was a predictive indicator in lumbar spine and left femur.

Effects of denosumab on bone mineral density in Japanese women with osteoporosis treated with aromatase inhibitors for breast cancer.

Adjuvant aromatase inhibitor (AI) therapy, for hormone receptor-positive breast cancer, in postmenopausal women is associated with bone loss, leading to an increased risk of fractures. Denosumab, an antibody raised against the receptor activator of nuclear factor-κB ligand, has been proven to protect against AI-induced bone loss. Hence, we aimed to determine whether denosumab is effective in postmenopausal Japanese women with osteoporosis, treated with AI. We prospectively evaluated the bone mineral density (BMD) in the lumbar spine and the bilateral femoral neck in 102 postmenopausal women with clinical hormone receptor-positive breast cancer, stages I-IIIA, during a postoperative period of 12 months. The other inclusion criteria for this study were: women that should receive AIs as adjuvant therapy and those with evidence of osteoporosis (lumbar spine or bilateral femoral neck BMD, equivalent to T-score classification of ≤ - 2.5) upon enrollment. The patients received supplemental calcium, vitamin D, and 60 mg of subcutaneous denosumab every 6 months. The BMD of the lumber spine increased by 4.9 and 6.6% at 6 and 12 months, respectively. An increase in BMD was observed at the femoral neck, bilaterally. Hypocalcemia ≥ grade 2, osteonecrosis of the jaw, and non-traumatic clinical fracture were not observed in this study. Our findings revealed that biannual treatment with denosumab is associated with a great increase of BMD in Japanese women receiving adjuvant AI therapy, irrespective of their previous history of AI therapy.

Effect of denosumab on low bone mineral density in postmenopausal Japanese women receiving adjuvant aromatase inhibitors for non-metastatic breast cancer: 24-month results.

BACKGROUND: Aromatase inhibitors (AI) have been established as the gold-standard therapy for postmenopausal patients. Worldwide, adjuvant denosumab at a dose of 60 mg twice per year reduces the risk of clinical fractures in postmenopausal patients with breast cancer who received AI. However, the efficacy of denosumab in the treatment of AI-associated bone loss had not been prospectively evaluated in Japan. Previously, we reported the 12-month effect of denosumab in Japanese patients for the first time; the primary endpoint was the change in the percentage of bone mineral density (BMD) of the lumbar spine from baseline to 12 months. METHODS: This secondary follow-up study prospectively evaluated the change in the percentage of BMD of the lumbar spine from baseline to 24 months. Postmenopausal women with early-stage, histologically confirmed, hormone receptor-positive, invasive breast cancer who were receiving or scheduled to receive AI were included. Denosumab was administered subcutaneously on day 1 of the study and then 6, 12, 18, and 24 months. The lumbar spine and bilateral femoral neck BMD was measured at baseline and 6, 12, 18, and 24 months. RESULTS: At 18 and 24 months, the lumbar spine BMD increased by 5.9 and 7.0%, respectively. The femoral neck BMD also increased. Grade ≥ 2 hypocalcemia, osteonecrosis of the jaw, and atypical femoral fractures did not occur. CONCLUSIONS: Our prospective study showed that semiannual treatment with denosumab was associated with continuously increased BMD in Japanese women receiving adjuvant AI therapy for up to 24 months, regardless of prior AI treatment.

[Bone and calcium metabolism associated with malignancy. Clinical Characteristics and Treatment of Cancer Treatment Induced Bone Loss(CTIBL)in Breast Cancer.]

Breast cancer is a typical hormone-dependent tumor and at the time of diagnosis more than 60% of breast cancers are positive for estrogen receptors and estrogen(E)is required for proliferation. Since breast cancer is a tumor easily to cause micrometastasis, adjuvant hormonal therapy(HT)for 5 to 10 years after surgery that suppresses the action of estrogen actively prevents recurrence is very popular. However, HT with aromatase inhibitor(AI)for postoperative postmenopausal breast cancer markedly reduces the E concentration in the body, leading to significant bone loss and fracture as known as aromatase inhibitor-induced bone loss(AIBL), a typical example of CTIBL. Under these circumstances, the usefulness of bone modifying agents as a supportive therapy to increase bone density and decrease fracture rate without interrupting the treatment of breast cancer became clear, mainly in Europe and the United States. And recently, our study revealed even in Japanese breast cancer patients denosumab injection every 6 months showed significant increase in bone density. The number of women suffering from breast cancer in Japan reaches approximately 90,000 per year, a considerable number is estimated as a preliminary group of CTIBL, so early appropriate measures are desired.

Effect of denosumab on bone mineral density in Japanese women with osteopenia treated with aromatase inhibitors for breast cancer: subgroup analyses of a Phase II study.

BACKGROUND: The aim of the study was to conduct subgroup analyses of therapeutic effects of 12-month denosumab therapy on the percentage change in bone mineral density (BMD) from baseline in the lumber spine and femoral neck. MATERIALS AND METHODS: We prospectively evaluated the BMD of the lumbar spine and femoral neck of 100 hormone receptor-positive, clinical stage I-IIIA postoperative postmenopausal breast cancer patients, for whom treatment with aromatase inhibitors (AIs) as adjuvant endocrine therapy was scheduled. The primary endpoint was the percent change in lumbar spine BMD from baseline to 12 months. Patient subgroups were analyzed according to baseline variables that are known risk factors for bone loss, including previous AI therapy, age, time since menopause, baseline body mass index (BMI), and baseline BMD T-score. RESULTS: At 12 months, lumbar spine BMD increased by 4.7%; the patients who were administered AI therapy prior to denosumab (n=70) demonstrated a 4.7% increase in BMD, and the patients who received denosumab at the start of AI therapy (n=30) demonstrated a 4.5% increase in BMD (p=0.8385). Additionally, 2.4% and 1.4% increases in BMD of the right and left femoral neck, respectively, were observed. Initiation of AI (with denosumab, before denosumab), type of AI (non-steroidal, steroidal), age (<65, ≥65 years), time since menopause (≤5, >5 years), BMI (<25, ≥25 kg/m2), and T-score (≤-1.0, >-1.0) of the right femoral neck were as follows: (2.2%, 2.5%, p=0.7773), (2.6%, 0.9%, p=0.1726), (2.5%, 2.3%, p=0.7594), (2.1%, 2.4%, p=0.2034), (2.1%, 2.9%, p=0.2034), and (2.3%, 2.7%, p=0.6823), respectively. Initiation of AI (with denosumab, before denosumab), type of AI (non-steroidal, steroidal), age (<65, ≥65 years), time since menopause (≤5, >5 years), BMI (<25, ≥25 kg/m2), and T-score (≤-1.0, >-1.0) of the left femoral neck were as follows: (1.0%, 1.5%, p=0.1972), (1.2%, 2.7%, p=0.2931), (1.4%, 1.3%, p=0.8817), (-0.1%, 1.6%, p=0.1766), (1.3%, 1.9%, p=0.6465), and (1.5%, 1.1%, p=0.6573), respectively. CONCLUSION: Twice-yearly treatment with denosumab was associated with increased BMD among Japanese women receiving adjuvant AI therapy, regardless of the baseline characteristics or skeletal site.

Effect of denosumab administration on low bone mineral density (T-score -1.0 to -2.5) in postmenopausal Japanese women receiving adjuvant aromatase inhibitors for non-metastatic breast cancer.

Although adjuvant aromatase inhibitor (AI) therapy is widely used in postmenopausal women with hormone receptor-positive breast cancer, it is known to be associated with bone loss and increased fracture risk. Denosumab, a fully human monoclonal antibody against the receptor activator of nuclear factor-κB ligand, has been shown to protect against AI-induced bone loss. However, the efficacy of denosumab in the treatment of AI-associated bone loss has not been prospectively evaluated in Japan. We prospectively monitored bone mineral density (BMD) of the lumbar spine and bilateral femoral necks in 100 postmenopausal women with hormone receptor-positive postoperative breast cancer of clinical stage I-IIIA in whom treatment with AI as adjuvant endocrine therapy was planned or had been ongoing. Study participants received supplemental calcium and vitamin D every day and denosumab (60 mg) subcutaneously every 6 months. At enrollment, patients were required to have evidence of low bone mass without meeting the criteria for osteoporosis. The primary endpoint was percentage change from baseline in lumbar spine BMD at month 12. At 6 and 12 months, lumbar spine BMD increased by 3.3 and 4.7%, respectively. BMD of the femoral necks also increased. Hypocalcemia of grade ≥2, osteonecrosis of the jaw, and non-traumatic clinical fracture did not occur. In conclusion, semi-annual treatment with denosumab was associated with increased BMD in Japanese women receiving adjuvant AI therapy, regardless of prior AI treatment.

Remarkable regression of massive deep vein thrombosis in response to intensive oral rivaroxaban treatment.

Deep vein thrombosis (DVT) is a common disease and is associated with pulmonary embolism (PE). Proximal iliofemoral DVT may lead to severe PE and chronic venous insufficiency. The standard therapy for DVT is anticoagulant therapy using heparin and a vitamin K antagonist, but a recent clinical study showed that rivaroxaban, an oral Xa inhibitor, was comparable to standard therapy and had less bleeding complications. Intensive high-dose anticoagulation is recommended during the initial 3 weeks of DVT treatment. The present report describes a case of a 77-year-old male showing a remarkable regression of DVT in response to rivaroxaban treatment within the initial 3 weeks of therapy and who did not experience any adverse events. His DVT was massive and was accompanied by proximal iliofemoral vein thrombus and iliac vein compression syndrome. Rivaroxaban, especially in intensive high-dose treatment, might be a safe and effective therapeutic choice for massive DVT.

Efficacy of zoledronic acid in postmenopausal Japanese women with early breast cancer receiving adjuvant letrozole: 12-month results.

Aromatase inhibitor-associated bone loss has not been proved in the Japanese or Asian women. The aim of this study was to evaluate an upfront or delayed strategy of bone protection therapy with zoledronic acid administered at 4 mg every 6 months in postmenopausal Japanese women with early breast cancer to compare with results of the Z-FAST and ZO-FAST studies in western countries. Postmenopausal women with hormone receptor positive early breast cancer receiving adjuvant letrozole were randomly assigned to receive either upfront or delayed-start zoledronic acid (4 mg intravenously every 6 months). The delayed group received zoledronic acid when lumbar spine (L(2)-L(4)) bone mineral density (BMD) decreased to less than young adult mean -2.0SD or when a nontraumatic fracture occurred. The primary endpoint of this study was to compare the percent change in L(1)-L(4) BMD at 12 months between the groups. Secondary endpoints included percent changes in L(2)-L(4) and total hip (TH) BMD. The upfront and delayed groups included 94 and 95 patients, respectively. At 12 months, L(1)-L(4), L(2)-L(4), and TH BMD significantly decreased by 2.0, 2.4, and 2.4%, respectively, in the delayed group. L(1)-L(4) BMD was 4.9% higher in the upfront group than in the delayed group (95% CI 3.9-5.8%; p < 0.001). L(2)-L(4) BMD was 5.6% higher (95% CI 4.5-6.6%; p < 0.001), and TH BMD was 4.4% higher (95% CI 3.3-5.4%; p < 0.001). At 12 months, upfront zoledronic acid therapy prevented bone loss in postmenopausal Japanese women who were receiving adjuvant letrozole, confirming the Z-/ZO-FAST study results in western populations.

Prediction of pathologic complete response to sequential paclitaxel and 5-fluorouracil/epirubicin/cyclophosphamide therapy using a 70-gene classifier for breast cancers.

BACKGROUND: Sequential administration of paclitaxel plus combined fluorouracil, epirubicin, and cyclophosphamide (P-FEC) is 1 of the most common neoadjuvant chemotherapies for patients with primary breast cancer and produces pathologic complete response (pCR) rates of 20% to 30%. However, a predictor of pCR to this chemotherapy has yet to be developed. The authors developed such a predictor by using a proprietary DNA microarray for gene expression analysis of breast tumor tissues. METHODS: Tumor samples were obtained from 84 patients with breast cancer by core-needle biopsy before the patients received P-FEC, and the gene expression profile was analyzed in those samples to construct a classifier for predicting pCR to P-FEC. In addition, the authors analyzed the gene expression profile of tumor tissues that were obtained at surgery from 105 patients with lymph node-negative and estrogen receptor-positive breast cancer who received adjuvant hormone therapy alone to determine the prognostic significance of the classifier. RESULTS: The 70-gene classifier for predicting pCR to P-FEC was constructed by using the training set (n = 50) and subsequently was validated successfully in the validation set (n = 34), revealing high sensitivity (88%; 95% confidence interval [CI], 47%-100%) and high negative predictive value (93%; 95% CI, 68%-100%). Specificity and positive predictive value were 54% (95% CI, 33%-73%) and 37% (95% CI, 16%-62%), respectively. Among the various parameters (estrogen receptor, progesterone receptor, human epidermal growth factor receptor 2, and Ki-67 status, etc), the 70-gene classifier had the strongest association with pCR (P = .015). In an additional study, genetically assumed complete responders were associated significantly (P = .047) with a poor prognosis. CONCLUSIONS: The 70-gene classifier that was constructed for predicting pCR to P-FEC for breast tumors was successful, with high sensitivity and high negative predictive value. The classifier also appeared to be useful for predicting the prognosis of patients with lymph node-negative and estrogen receptor-positive breast cancer who receive adjuvant hormone therapy alone.

Study of low-dose capecitabine monotherapy for metastatic breast cancer.

BACKGROUND: Capecitabine is an established therapy for metastatic breast cancer. In Japan, a 4 weekly regimen is often used, but data for this schedule in the first-line setting are lacking. METHODS: Metastatic breast cancer patients who had received no chemotherapy for recurrent disease received capecitabine 825 mg/m(2) twice daily, on days 1-21 of a 28-day cycle until disease progression or unacceptable toxicity. The primary endpoint was response rate. RESULTS: In 33 eligible patients, median age was 53 years (range 27-73). Prior adjuvant therapy included an anthracycline in 90% and a taxane in 40%. The response rate was 18%; a further 24% had stable disease for >or=6 months. Median progression-free and overall survival were 6.9 and 24.8 months, respectively. The only grade 3 events were neutropenia (6%) and hand-foot syndrome (15%). CONCLUSIONS: These preliminary results confirm previous data showing that a lower capecitabine dose is an active and well-tolerated first-line therapy for metastatic breast cancer.

Genetic polymorphisms of CYP2D6 10 and CYP2C19 2, 3 are not associated with prognosis, endometrial thickness, or bone mineral density in Japanese breast cancer patients treated with adjuvant tamoxifen.

BACKGROUND: The authors investigated the impact of the genetic polymorphisms cytochrome P450 (CYP) family 2, subfamily D, polypeptide 6, allele 10 (CYP2D6 10) and CYP family 2, subfamily C, polypeptide 19, allele 2, 3 (CYP2C19 2, 3) on disease recurrence in patients with breast cancer who received adjuvant tamoxifen and evaluated the impact of those polymorphisms on endometrial thickness, bone mineral density (BMD), and serum total cholesterol levels. METHODS: Patients with primary breast cancer (n=173) who had hormone receptor-positive tumors and who also received adjuvant tamoxifen were included in the current study. Genetic polymorphisms of CYP2D6 10 and CYP2C19 2, 3 were analyzed. RESULTS: Recurrence-free survival (RFS) rates did not differ significantly between patients with the CYP2D6 10/10 genotype (n=40) and patients with the CYP2D6 wild-type (wt)/wt or wt/10 genotype (n=133) or between patients with the CYP2C19 2/2, 2/3, or 3/3 genotypes (n=41) and patients with the CYP2C19 wt/wt, wt/2, or wt/3 genotype (n=132). Multivariate analysis indicated that, even after adjustment for well established prognostic factors, these CYP2D6 or CYP2C19 genotypes were not associated significantly with the RFS rate. Moreover, these genotypes did not affect endometrial thickness, BMD, or total cholesterol levels 1 year after the start of tamoxifen treatment. CONCLUSIONS: Neither the CYP2D6 10/10 genotype nor the CYP2C19 genotype is likely to have a clinically significant impact on prognosis, endometrial thickness, BMD, or total cholesterol levels in Japanese patients with breast cancer who are treated with adjuvant tamoxifen.

[Clinical features of paclitaxel-induced peripheral neuropathy and role of Gosya-jinki-gan].

Paclitaxel (PTX) is frequently used for a chemotherapy of breast cancer and gynecologic cancer. Besides a bone-marrow depression and hypersensitive reaction, the peripheral neuropathy is one of the serious adverse events of PTX. The mechanism of peripheral neuropathy has not been clarified, and few agents have been reported to be effective for the treatment and the prevention of that. Recently, it has been reported that Gosya-jinki-gan is useful for the PTX induced peripheral neuropathy, so we carried a retrospective study(n=82)to evaluate the effectiveness of Gosya-jinkigan with the medical records. It is suggested that peripheral neuropathy developed more rapidly in sequential administration of PTX every week than in administration in 4 weeks cycles consisting of 3 weeks on and 1 week off(5.4w vs. 9.4w). We have also found that Gosya-jinki-gan was possibly effective for the treatment and the prevention of peripheral neuropathy. Additionally Gosya-jinki-gan might be more effective for peripheral neuropathy when it is administered from the beginning of chemotherapy including PTX.

Incidence of joint symptoms and bone fractures in Japanese postmenopausal breast cancer patients treated with adjuvant anastrozole.

PURPOSE: Incidence of joint symptoms and bone fractures as well as changes in bone mineral density (BMD) in Japanese postmenopausal breast cancer patients treated with adjuvant anastrozole were investigated to determine whether there is an ethnic difference from Caucasian patients in the incidence of these adverse events of anastrozole. METHODS: Adjuvant anastrozole was used to treat 348 postmenopausal breast cancer patients for a median period of 22 months. Adverse events of anastrozole including joint symptoms, loss of BMD, and bone fracture were investigated by means of chart review. RESULTS: Joint symptoms developed in 96 (27.5%) patients. Age (younger than 65) and prior chemotherapy was strongly associated with an increased risk of joint symptoms. Annual fracture incidence was 0.86 and 0.85% and lumbar BMD decreased by 1.3 and 2.8% at 1 and 2 years, respectively. In comparison, the ATAC trial reported corresponding figures of 2.0 and 2.7 and of 2.2 and 4.0%. CONCLUSION: Incidence and risk factors of joint symptoms are similar for Japanese and Caucasian patients, but the former tend to show a smaller decrease in BMD and a lower incidence of bone fractures, probably due to ethnic difference in the hormonal milieu.

Capecitabine and paclitaxel combination chemotherapy for inoperable or recurrent breast cancer: a phase I dose-finding study by the Kinki Breast Cancer Study Group.

BACKGROUND: The combination of capecitabine and paclitaxel (XP) has demonstrated synergistic antitumor activity in preclinical models. Three-weekly XP regimens have demonstrated excellent efficacy in phase II and III trials in metastatic breast cancer. We conducted a dose-finding study to identify the recommended 4-weekly XP regimen in patients with inoperable or recurrent breast cancer for phase II evaluation. METHODS: Eligible patients had inoperable or recurrent breast cancer previously treated with chemotherapy (but not capecitabine or paclitaxel) in the (neo)adjuvant or metastatic setting. Each 4-week treatment cycle consisted of escalating doses of capecitabine (628 or 829 mg/m(2) twice daily [b.i.d.] on days 1-21) and paclitaxel (80 or 90 mg/m(2) on days 1, 8, and 15). Dose-limiting toxicities (DLT) were evaluated during the first two cycles. RESULTS: Nine patients were treated. At dose level 1 (capecitabine 628 mg/m(2) b.i.d. plus paclitaxel 80 mg/m(2)), one patient experienced a DLT (grade 3 non-hematologic toxicity). There were no further DLTs at dose level 1 or 2. Although the MTD was not reached, dose level 2 (capecitabine 829 mg/m(2) b.i.d., days 1-21, plus paclitaxel 80 mg/m(2), days 1, 8, and 15, every 28 days) is recommended for phase II evaluation, taking into consideration the single-agent doses used in Japan and the doses identified in Western studies of 3-weekly XP. The overall response rate was 44%; all patients treated at dose level 2 achieved a partial response. CONCLUSIONS: This 4-weekly XP regimen was well tolerated, active in patients with pretreated advanced breast cancer, and could be given as outpatient treatment. These results are consistent with findings of phase II and III trials evaluating 3-weekly regimens, and indicate that further investigation of a 4-weekly XP regimen is warranted.

[The feasibility of FEC (75) as adjuvant chemotherapy for Japanese breast cancer patients].

Recently, high-dose FEC (fluorouracil, epirubicin, and cyclophosphamide) has been increasingly used in adjuvant chemotherapy for breast cancer in Japan. However, the safety and tolerability of high-dose FEC are not well evaluated in Japanese breast cancer patients. We studied the feasibility of FEC (75) (fluorouracil: 500 mg/m(2), epirubicin: 75 mg/m(2), and cyclophosphamide:500 mg/m(2), q 3 w, 6 cycles) as adjuvant chemotherapy for 59 primary breast cancer patients. Out of these patients, 56 (94.9%) finished 6 cycles-FEC. The mean epirubicin dose received was 431.7 mg/m(2) (95.9% of the intended dose of 450 mg/m(2)). Forty-five (76.2%) of 59 patients experienced neutropenia of grade 3 or 4, while the rates of febrile neutropenia (grade 3) and infection (grade 2) were 3.4% and 10.2%, respectively. Anemia (88.2%), fatigue (42.4%), nausea (40.6%), liver dysfunction (40.7%), and vomiting (18.7%) occurred, however most of them were mild and categorized into grade 1 or 2. No patients developed any cardiac failure symptoms. This study shows FEC (75) is well tolerable as adjuvant chemotherapy for Japanese breast cancer patients.

Down-regulation of intratumoral aromatase messenger RNA levels by docetaxel in human breast cancers.

PURPOSE: The reason why chemotherapy induces resistance to subsequent hormonal therapy remains to be clarified in postmenopausal breast cancers. We hypothesized that chemotherapy might down-regulate the intratumoral biosynthesis of estrogens. Thus, we have studied the influence of chemotherapy (docetaxel) on intratumoral aromatase mRNA expression because aromatase is a key enzyme for intratumoral biosynthesis of estrogens. EXPERIMENTAL DESIGN: The mRNA levels of aromatase and its inducers [tumor necrosis factor alpha (TNF-alpha), interleukin 6 (IL-6), and cyclooxygenase 2 (COX-2)] were determined by a real-time polymerase chain reaction assay in breast cancer tissues obtained before and after neoadjuvant chemotherapy with docetaxel (four cycles of 60 mg/m2 every 3 weeks) in 16 postmenopausal patients with estrogen receptor (ER)- and/or progesterone receptor (PR)-positive breast cancers. ER and PR levels in tumor tissues were also determined by enzyme immunoassay before and after chemotherapy. RESULTS: The intratumoral aromatase mRNA levels decreased significantly (P < 0.05) after chemotherapy from 0.84 +/- 0.28 (mean +/- SE) to 0.47 +/- 0.28. The intratumoral TNF-alpha mRNA levels also decreased significantly (P < 0.05) after chemotherapy from 2.40 +/- 0.52 to 0.95 +/- 0.25. On the contrary, the intratumoral IL-6 and COX-2 mRNA levels showed a marginally significant increase (P = 0.07) and a significant increase (P < 0.05), respectively, after chemotherapy. PR levels showed a marginally significant decrease (P = 0.08) after chemotherapy, whereas ER levels were almost constant before and after chemotherapy. CONCLUSIONS: Antitumor activity of docetaxel is mediated, at least in part, through a down-regulation of aromatase expression in tumor tissues, resulting in the suppression of intratumoral estradiol synthesis. Aromatase expression seems to be regulated mostly by TNF-alpha, but not IL-6 and COX-2.

Influence of adjuvant tamoxifen treatment on bone mineral density and bone turnover markers in postmenopausal breast cancer patients in Japan.

The effect of adjuvant tamoxifen treatment on bone mineral density (BMD) and bone turnover markers was studied in postmenopausal breast cancer patients. The relationship of tamoxifen's effect with the genetic polymorphisms of estrogen receptor (ER)-alpha and ER-beta gene was also studied. Twenty-one postmenopausal breast cancer patients were given tamoxifen (20 mg/day) as the adjuvant treatment after the surgery. BMD of the lumbar supine (dual emission X-rays absorptiometry) and bone resorption (deoxypyridinoline, aminoterminal telopeptide of type I collagen, and carboxyterminal telopeptide of type I collagen) and formation (propeptide of type I procollagen, osteocalcin, and bone-specific alkaline phosphatase) markers were examined at baseline (before the surgery), 6 and 12 months after the start of tamoxifen treatment. Genetic polymorphisms analyzed were TA dinucleotide repeats polymorphism in the promoter region and PvuII and XbaI restriction fragment length polymorphism for the ER-alpha gene and the CA dinucleotide repeats polymorphism in the intron 5 for the ER-beta gene. Tamoxifen significantly increased BMD of the lumbar spine at both 6 (P<0.01) and 12 months (P<0.01) after the start of tamoxifen as compared with that at baseline. The mean percent increase in BMD was 3.3% at 6 months and 2.7% at 12 months. All bone resorption and formation markers significantly decreased at both 6 and 12 months. Among the four genetic polymorphisms studied, only ER-beta CA repeat polymorphism was found to be significantly associated with BMD at 12 months, i.e. BMD of the 21 CA repeats allele carriers was significantly higher than that of the non-carriers (P=0.025). These results suggest that tamoxifen increases BMD of the lumbar supine by reducing the bone turnover in postmenopausal breast cancer patients, and this bone restoring effect of tamoxifen is more marked in ER-beta 21 CA repeats allele carriers than non-carriers.