Biomedical subjects

Masakazu Toi

Publications and source records attributed to Masakazu Toi.

At least 19 recordsLinked to original sources

PubMed2026

Clinical and Molecular Evaluation of HER2-Low and HER2-Ultralow Breast Cancer in the Penelope-B Clinical Trial Cohort.

The DestinyBreast (DB)04 and DB06 trials have shown clinical activity of trastuzumab-deruxtecan (T-DXd) in HER2-low and HER2-ultralow metastatic breast cancer. The identification of HER2-low and HER2-ultralow breast cancer is therefore essential for personalized therapy with T-DXd. We evaluated 723 residual tumors from the Penelope-B trial (NCT01864746) and correlated different levels of HER2 protein expression with prognosis and messenger RNA (mRNA) profiles, including HER2 transcripts. In Penelope-B, 57.68% (n = 417) of 723 residual tumors were HER2 low. The HER2-ultralow category was assigned to 109 (15.08%) tumors, and 197 (27.25%) tumors were completely HER2 negative (HER2 0). In Kaplan-Meier analysis, there were no survival differences among these 3 subgroups. There was no significant difference in HER2 mRNA expression between HER2-0 and HER2-ultralow tumors (P = .08). In contrast, there was a highly significant difference in HER2 mRNA expression between HER2-ultralow and HER2-low tumors (P < .0001) and between HER2-low and HER2-positive tumors (P < .0001). The extracellular protease cathepsin L, which has been suggested as a biomarker for extracellular cleavage of T-DXd, was detectable in all HER2-related subgroups and was a negative prognostic factor for invasive disease-free survival and overall survival (P = .0001) in preneoadjuvant core biopsies. In our study, we were able to characterize HER2 low as a clinically relevant and molecular defined tumor group with significantly increased HER2 expression. In contrast, for HER2 ultralow, we did not observe a defined molecular phenotype, despite the clinically relevant regulatory approval of T-DXd also in the ultralow subgroup. Additional investigations are needed to identify biomarkers beyond HER2 for T-DXd response as a basis for refined criteria for treatment eligibility.

Adult↗

PubMed2025

Neoadjuvant palbociclib in women with operable, hormone receptor-positive breast cancer.

The addition of a cyclin-dependent kinase 4/6 (CDK4/6) inhibitor to endocrine therapy augments biological response in breast cancer. This phase III randomized, double-blind study evaluated the efficacy of adding palbociclib to neoadjuvant endocrine therapy (NET) for operable, hormone receptor-positive human epidermal growth factor receptor 2 (HER2)-negative breast cancer. Patients randomly received 16 weeks of endocrine therapy (letrozole for postmenopausal and tamoxifen plus ovarian function suppression for pre-/perimenopausal patients) plus palbociclib or placebo. The co-primary endpoints included preoperative endocrine prognostic index (PEPI) score and EndoPredict (EPclin) risk score according to the gatekeeping procedure. Of 141 randomized patients, 130 completed the treatment with surgical samples evaluable for endpoints in 126 patients. The proportion of patients with a low, moderate, and high PEPI score was 15.2, 50.0, and 34.8% in the palbociclib arm and 13.3, 55.0, and 31.7% in the placebo arm, respectively, with no statistical difference (one-sided P = 0.563). Statistical analysis was not performed on EPclin risk score. No new safety signals were reported. Permanent treatment discontinuation by adverse events was reported for seven (9.7%) and zero patients in the palbociclib and placebo arms, respectively. In conclusion, the addition of palbociclib to NET did not improve the efficacy. ClinicalTrials.gov NCT03969121.

Humans↗

PubMed2006

Mechanical analysis of tumor growth regression by the cyclooxygenase-2 inhibitor, DFU, in a Walker256 rat tumor model: importance of monocyte chemoattractant protein-1 modulation.

Cyclooxygenase (COX)-2 inhibition results in tumor regression; however, little is known about the mechanism. In the present study, using a Walker256 tumor model and a rat bone marrow-derived endothelial cell line TR-BME-2, we analyzed the effects of a new selective COX-2 inhibitor, 5,5-dimethyl-3-(3-fluorophenyl)-4-(4-methylsulphonyl)phenyl-2-(5H)-furanone (DFU), on the production of chemokines and growth factors and on the neovascularization. The oral administration of DFU (5 mg/kg/d) significantly suppressed the tumor growth with decreasing microvessel density in vivo, although it showed no direct inhibition of Walker256 cell proliferation in vitro. It was newly found that the recruitment of systemically injected TR-BME-2 cells into the tumor site was significantly inhibited by DFU treatment. In addition, we found that DFU significantly reduced the production of monocyte chemoattractant protein-1 (MCP-1) both in tumor tissues and in the systemic circulation (P < 0.001 and P < 0.001, respectively). Such reduction was not observed in other chemotactic factors, vascular endothelial growth factor and stromal cell-derived factor-1. The induced chemotaxis of TR-BME-2 by serum of tumor-bearing rats was significantly reduced in DFU-treated rat serum, although DFU showed no direct inhibition for TR-BME-2 cells, either cell growth or chemotaxis. Treatment with neutralizing antibodies to soluble mediators, including MCP-1, significantly suppressed the chemotaxis. Regarding the down-regulation machinery of MCP-1 production in vivo, tumor-associated macrophages seem to play crucial roles, because DFU eliminated MCP-1 production in the activated macrophages remarkably but not in Walker256 tumor cells in vitro. In conclusion, COX-2 inhibitor DFU exerts tumor regression activity in a Walker256 tumor model by suppressing MCP-1 production in tumor tissues and in the circulation.

Animals↗

PubMed2006

Early breast cancer.

Breast cancer remains a common disease throughout the world. Here we review new knowledge about early breast cancer obtained during the past 5 years. The prognosis of early breast cancer is generally favorable. Especially, ductal carcinoma in situ has been regarded as a non-life-threatening disease. Therefore, early diagnosis and early onset of the treatment has been important. Early age at menarche, late age at first birth, and late age at menopause are related to breast cancer risk. Examination by mammography and ultrasonography is still the most effective means of detection for premenopausal and postmenopausal women, respectively. Additionally, there have been important advances in MRI, sentinel lymph node biopsy, breast-conserving surgery, partial breast irradiation, neoadjuvant systemic therapy, and adjuvant systemic therapy. Another approach to keeping the disease under control is the elucidation of breast cancer's molecular biological features. Assessment of potential molecular targets can lead to early diagnosis and molecular targeted treatment.

Breast Neoplasms↗

PubMed2006

Cost-effective treatment options in first-line therapy for advanced breast cancer in Japan.

Concern regarding the economic aspect of cancer care has been increasing in the face of mounting healthcare expenditure in Japan. The need, not only for effective, but also for efficient treatment options in breast cancer care have been recognized in a broader context. In clinical practice, treatment options in first-line therapy for advanced breast cancer have become similar to those in Western countries in the past 5 to 10 years in the context of so-called 'evidence-based medicine' employing clinical evidence; whereas evidence of cost-effectiveness has been less acknowledged. Limited economic evidence suggests that current Japanese practice in first-line hormonal therapy is cost-effective. However, the efficiency of other options, such as chemotherapy, remains unknown. The expanding use of an expensive molecular-targeting agent, trastuzumab, has great implications for a treatment algorithm for breast cancer as well as for cost-effectiveness of care. Trastuzumab, of which use in first-line therapy was not found to be cost-effective in Western countries, is expected to be used for a number of HER2-overexpressing primary breast cancers in Japan. The extension of indication of this single agent would increase national healthcare expenditure by 0.1%. The authors believe explicit discussion on value for money of new expensive drugs would be unavoidable, not only among health policy makers, but also leading breast cancer specialists in Japan in the near future.

Antibodies, Monoclonal↗

PubMed2006

Who benefits from hormone therapy?

Not all hormone receptor (HR)-positive tumors respond to hormone therapy, although hormone therapy has brought significant benefits to breast cancer patients. In order to improve the efficacy of hormone therapy, a variety of new approaches are currently being tested in such as extended adjuvant therapy, selection of responders using array-based techniques and combination therapy with signal transduction inhibitors. It is therefore necessary to distinguish between highly hormone responsive tumors and relatively less hormone sensitive tumors. Through reviewing recent outcomes of clinical trials, these issues are summarized and discussed in this review.

Adult↗

PubMed2006

Issues in the assessment of the pathologic effect of primary systemic therapy for breast cancer.

BACKGROUND: Emerging evidence suggests that induction of pathologic complete response (pCR) after primary systemic therapy (PST) is, at least to some extent, predictive of survival. However, standards for processing surgical specimens and for histopathologic evaluation of the pathologic response to therapy appear to be lacking. METHODS: To perform a systematic review of representative articles on this topic, a computerized (MEDLINE) search was undertaken followed by a manual search based on the reference lists of the publications identified. RESULTS: Several classification systems have been used to assess pathologic response to PST, the term pCR has not been applied in a consistent standardized manner, and only limited information is available about the reliability and validity of these classification systems. However, definitions of pCR can be summarized as follows: near pCR, only focal invasive tumor residues in the removed breast; quasi pCR, total or near total disappearance of invasive tumor in the removed breast; pCRinv, only in situ tumor residual in the removed breast; comprehensive pCR, no evidence of residual invasive tumor in the removed breast; strict pCR, disappearance of all tumor cells in the removed breast; comprehensive pCR (br+n), no evidence of residual invasive tumor in the breast and axillary nodes; strict pCR (br+n), no malignant tumor cells in the removed breast and axillary nodes. Comparison of the use of the term "pCR" in various trials reveals that it is not applied equivalently in these studies. CONCLUSION: Assessment of pCR needs to be standardized, with verification for reliability and validity. For now, the non-equivalency in the definition of pCR should be taken into account when comparing the results of PST.

Antineoplastic Agents↗

PubMed2006

A pilot phase II study of capecitabine in advanced or recurrent breast cancer.

BACKGROUND: A pilot phase II study was conducted to evaluate the efficacy and safety of the Japanese intermittent regimen of capecitabine (Xeloda) in patients with advanced or recurrent breast cancer. METHODS: A total of 23 patients who had received no more than one prior chemotherapy regimen received oral 828 mg/m2 capecitabine twice daily for 3 weeks followed by a 1-week rest period. The response to capecitabine was evaluated in 22 patients (one patient ineligible). RESULTS: The overall response rate was 45.5% (95% CI, 24.4-67.8%), including 1 complete response (4.5%) and 9 patients with partial response (40.9%). A further 7 patients (31.8%) had stable disease. The median duration of response was 7.2 months (range, 3.0-15.8 months) and the median time to progression was 6.4 months (95% CI, 4.1-15.1 months). Treatment-related adverse events >or= grade 3 were observed in 7 patients (30.1%). CONCLUSION: Intermittent capecitabine therapy (828 mg/m(2) twice daily for 3 weeks followed by a 1-week rest period) was shown to be effective and well tolerated as second-line treatment for advanced or recurrent breast cancer. The Japanese regimen is worthy of further study in larger numbers of patients in phase II / III clinical trials.

Administration, Oral↗

PubMed2006

The association between vascular endothelial growth factor-C, its corresponding receptor, VEGFR-3, and prognosis in primary breast cancer: a study with 193 cases.

Lymphangiogenesis plays an important role in several normal and pathological conditions, such as wound healing, pathogen infection, inflammation or the metastasis formation of endothelial malignancies. Vascular endothelial growth factor-C (VEGF-C) and VEGF-D are important and specific regulatory factors for lymphatic endothelial proliferation and lymphangiogenesis. Both growth factors mediate their biological activity mainly by VEGF receptor-3 (VEGFR-3, Flt-4). In this study, we measured intratumoral levels of VEGF-C and VEGFR-3 through enzyme-linked immunosorbent assay (ELISA) in 193 primary breast cancer tissues and examined their prognostic values. A significant correlation was found between the VEGF-C and VEGFR-3 protein levels. High VEGF-C levels were associated with low-grade tumors and a smaller size. Univariate analysis showed that high VEGF-C was significantly associated with a favourable prognosis for disease-free survival (DFS) and overall survival (OS). No significant prognostic value of VEGFR-3 was detected. Multivariate analysis confirmed the independent prognostic value of VEGF-C. The intratumoral VEGF-C level is a significant prognostic indicator of primary breast cancer. An investigation of the mechanisms of VEGF-C protein processing in human cancer tissue should be carried out in the future.

Adult↗

PubMed2006

[Neoadjuvant Chemotherapy in breast cancer].

Neoadjuvant chemotherapy for breast cancer was originally used in locally advanced inoperable disease in order to achieve surgical resection. It was then extended to operable breast cancer with a view to downstaging tumors to facilitate breast-conserving surgery. Long-term results from randomized studies have shown no difference in disease-free or overall survival between neoadjuvant and adjuvant chemotherapy. The main benefit of neoadjuvant chemotherapy is its ability to downstage large tumors with a view to treatment by breast-conserving surgery. Since pathological complete response is thought to be main factor to achieve long-term survival, development of new agent or novel combination treatment is needed.

Antineoplastic Combined Chemotherapy Protocols↗

PubMed2005

Efficient intervention of growth and infiltration of primary adult T-cell leukemia cells by an HIV protease inhibitor, ritonavir.

Adult T-cell leukemia (ATL), an aggressive malignancy of CD4+ T cells associated with human T-cell leukemia virus type I (HTLV-I) infection, carries a very poor prognosis because of the resistance of leukemic cells to any conventional regimen, including chemotherapy. We examined the effect of ritonavir, an HIV protease inhibitor, on HTLV-I-infected T-cell lines and primary ATL cells and found that it induced apoptosis and inhibited transcriptional activation of NF-kappaB in these cells. Furthermore, ritonavir inhibited expression of Bcl-xL, survivin, c-Myc, and cyclin D2, the targets of NF-kappaB. In nonobese diabetic/severe combined immunodeficient (NOD/SCID)/gammacnull (NOG) mice, ritonavir very efficiently prevented tumor growth and leukemic infiltration in various organs of NOG mice at the same dose used for treatment of patients with AIDS. Our data indicate that ritonavir has potent anti-NF-kappaB and antitumor effects and might be clinically applicable for treatment of ATL. These results would provide a new concept and novel platform for new drug development of leukemia and solid cancer as well.

Adult↗

PubMed2005

Significance of HDAC6 regulation via estrogen signaling for cell motility and prognosis in estrogen receptor-positive breast cancer.

Histone deacetylase (HDAC) 6 is a subtype of the HDAC family; it deacetylates alpha-tubulin and increases cell motility. Here, we investigate the impact of an alteration of HDAC6 expression in estrogen receptor alpha (ER)-positive breast cancer MCF-7 cells, as we identified that HDAC6 is a novel estrogen-regulated gene. MCF-7 treated with estradiol showed increased expression of HDAC6 mRNA and protein and a four-fold increase in cell motility in a migration assay. Cell motility was increased to the same degree by stably transfecting the HDAC6 expression vector into MCF-7 cells. In both cases, the cells changed in appearance from their original round shape to an axon-extended shape, like a neuronal cell. This HDAC6 accumulation caused the deacetylation of alpha-tubulin. Either the selective estrogen receptor modulator tamoxifen (TAM) or the pure antiestrogen ICI 182,780 prevented estradiol-induced HDAC6 accumulation and deacetylation of alpha-tubulin, leading to reduced cell motility. Tubacin, an inhibitory molecule that binds to the tubulin deacetylation domain of HDAC6, also prevented estradiol-stimulated cell migration. Finally, we evaluated HDAC6 protein expression in 139 consecutively archived human breast cancer tissues by immunohistochemical staining. The prognostic analyses for these patients revealed no significant differences based on HDAC6 expression. However, subset analysis of ER-positive patients who received adjuvant treatment with TAM (n = 67) showed a statistically significant difference in relapse-free survival and overall survival in favor of the HDAC6-positive group (P < 0.02 and P < 0.05, respectively). HDAC6 expression was an independent prognostic indicator by multivariate analysis (odds ratio = 2.82, P = 0.047). These results indicate the biological significance of HDAC6 regulation via estrogen signaling.

Anilides↗

PubMed2005

Late phase II clinical study of vinorelbine monotherapy in advanced or recurrent breast cancer previously treated with anthracyclines and taxanes.

BACKGROUND: At present, it is one of the most important issues for the treatment of breast cancer to develop the standard therapy for patients previously treated with anthracyclines and taxanes. With the objective of determining the usefulness of vinorelbine monotherapy in patients with advanced or recurrent breast cancer after standard therapy, we evaluated the efficacy and safety of vinorelbine in patients previously treated with anthracyclines and taxanes. METHODS: Vinorelbine was administered at a dose level of 25 mg/m(2) intravenously on days 1 and 8 of a 3 week cycle. Patients were given three or more cycles in the absence of tumor progression. A maximum of nine cycles were administered. RESULTS: The response rate in 50 evaluable patients was 20.0% (10 out of 50; 95% confidence interval, 10.0-33.7%). Responders plus those who had minor response (MR) or no change (NC) accounted for 58.0% [10 partial responses (PRs) + one MR + 18 NCs out of 50]. The Kaplan-Meier estimate (50% point) of time to progression (TTP) was 115.0 days. The response rate in the visceral organs was 17.3% (nine PRs out of 52). The major toxicity was myelosuppression, which was reversible and did not require discontinuation of treatment. CONCLUSION: The results of this study show that vinorelbine monotherapy is useful in patients with advanced or recurrent breast cancer previously exposed to both anthracyclines and taxanes.

Adult↗

PubMed2005

N(1),N(12)-Diacetylspermine as a sensitive and specific novel marker for early- and late-stage colorectal and breast cancers.

PURPOSE: N(1),N(12)-diacetylspermine (DiAcSpm) in the urine of colorectal and breast cancer patients was examined to establish its usefulness as a novel diagnostic tool for detecting these cancers at clinically early stages. EXPERIMENTAL DESIGN: Urine samples from 248 colon cancer patients and 83 breast cancer patients as well as 51 patients with benign gastrointestinal diseases treated in Tokyo Metropolitan Komagome Hospital during the period of August 1999 to January 2004 were collected. DiAcSpm was analyzed by ELISA and its sensitivity for malignant conditions was compared with that of serum carcinoembryonic antigen (CEA), CA19-9, and CA15-3. RESULTS: The sensitivity of urinary DiAcSpm for colon cancer patients (n = 248) was 75.8% (mean +/- 2 SD for 52 healthy controls as a cutoff value), which was markedly higher than the sensitivities of serum CEA (39.5%, P < 0.0001) and CA19-9 (14.1%, P < 0.0001). DiAcSpm was elevated in 60% of tumor-node-metastasis cancer stage 0 + I patients, whereas only 10% (P < 0.0001) and 5% (P < 0.0001) of these patients were CEA- and CA19-9-positive, respectively. The sensitivity of urinary DiAcSpm for 83 cases of breast cancer (60.2%) was higher than the sensitivities of CEA (37.3%, P = 0.0032) and CA15-3 (37.3%, P = 0.0032). DiAcSpm was elevated in 28% of tumor-node-metastasis stage I + II patients, whereas only 3% (P = 0.0064) and 0% (P = 0.001) of these patients were CEA- and CA15-3-positive, respectively. CONCLUSION: The observations indicate that urinary DiAcSpm is a more sensitive marker than CEA, CA19-9, and CA15-3 and that it can efficiently detect colorectal and breast cancers at early stages.

Adult↗

PubMed2005

Targeting of nuclear factor kappaB Pathways by dehydroxymethylepoxyquinomicin, a novel inhibitor of breast carcinomas: antitumor and antiangiogenic potential in vivo.

We previously designed and synthesized the new nuclear factor kappaB (NF-kappaB) inhibitor dehydroxymethylepoxyquinomicin (DHMEQ) derived from the structure of the antibiotic epoxyquinomicin C. We looked into the effect of DHMEQ on cellular phenotypes and tumor growth in mice injected with human breast carcinoma cell line MDA-MB-231 or MCF-7. In estrogen-independent breast adenocarcinoma cell line MDA-MB-231, NF-kappaB is constitutively activated. The addition of DHMEQ (10 microg/mL) completely inhibited the activated NF-kappaB for at least 8 hours. On the other hand, NF-kappaB is not activated in estrogen-dependent MCF-7 cells. In this cell line, DHMEQ completely inhibited the tumor necrosis factor-alpha-induced activation of NF-kappaB. DHMEQ did not inhibit the degradation of IkappaB but inhibited the nuclear translocation of NF-kappaB by both p65/p50 and RelB/p52 pathways. MDA-MB-231 cells secrete interleukin (IL)-6 and IL-8 without stimulation, and DHMEQ decreased the secretion levels of both cytokines. When MDA-MB-231 or MCF-7 cells were stimulated by tumor necrosis factor-alpha, the inhibitory effects of DHMEQ were still maintained. I.p. administration of DHMEQ (thrice a week) significantly inhibited the tumor growth of MDA-MB-231 (12 mg/kg) or MCF-7 (4 mg/kg) in severe combined immunodeficiency mice. No toxicity was observed during the experiment, including the loss of body weight. An immunohistological study on resected MCF-7 tumors showed that DHMEQ inhibited angiogenesis and promoted apoptosis. Furthermore, in Adriamycin-resistant MCF-7 cells highly expressing multidrug resistance gene-1, DHMEQ also exhibited the above capability, including down-regulation of IL-8. Thus, DHMEQ might be a potent drug for the treatment of various breast carcinomas by inhibiting the NF-kappaB activity.

Angiogenesis Inhibitors↗

PubMed2005

Clinical significance of estrogen receptor beta in breast cancer.

Ever since the estrogen receptor (ER) beta was discovered in 1996, we have been trying to determine its value as a prognostic and/or predictive factor in breast cancer and its potential as a novel target for pharmacological intervention. Recent progress in cellular experiments has shown that ERbeta works as counter partner of ERalpha through inhibition of the transactivating function of ERalpha by heterodimerization, distinct regulation on several specific promoters by ERalpha or ERbeta, and ERbeta-specific regulated genes which are probably related to its anti-proliferative properties. Accumulated data from protein studies in breast cancer tissues indicate that positive expression of ERbeta appears to correlate with a favorable prognosis. Although the number of studies is small, a positive response to tamoxifen treatment is observed in both ERalpha- and ERbeta-positive populations. The significance of ERbeta2/cx, a splicing variant of ERbeta, remains controversial and needs to be analyzed in further studies. We postulate that a combined evaluation of ERbetacx with progesterone receptor may help the stratification of ERalpha-positive breast cancer. Epidemiological studies of hormone replacement therapy and isoflavone (genistein) consumption indicate the possible contribution of ERbeta-specific signaling in breast cancer prevention. A selective estrogen receptor modulator, which works as an antagonist of ERalpha and an agonist of ERbeta, may be a promising chemo-preventive treatment.

Breast Neoplasms↗

PubMed2005

Trastuzumab: updates and future issues.

Trastuzumab has had an enormous impact on the clinical management of breast cancer: the survival of Her-2-positive metastatic breast cancer patients has improved significantly and tumor Her-2 status has been built into the decision-making tree for primary breast cancer patients. Several pioneering studies have shown that trastuzumab-combined chemotherapy elicits high levels of pathological complete response in the neoadjuvant setting. Currently, therefore, a more precise understanding of the mechanisms of therapeutic response is needed so that trastuzumab-based therapies can be optimized more individually. It might also be important to investigate, with greater depth, the interaction between the Her-axis and the hormone-axis. This short review describes and discusses these topics.

Antibodies, Monoclonal↗

PubMed2005

A Japanese phase I study of continuous oral capecitabine in patients with malignant solid tumors.

BACKGROUND: This study aimed to evaluate the tolerability and pharmacokinetics of capecitabine, given twice daily for 6 weeks without interruption, and to identify the maximum tolerated dose (MTD) and the suggested phase II schedule. METHODS: The initial dose of capecitabine was 251 mg/m2 twice daily, without interruption, and a dose escalation schedule was planned according to a modified Fibonacci scheme. Patients received oral capecitabine twice daily for at least 6 weeks unless grade 3 or 4 toxicity was observed. Blood and urine samples were collected for pharmocokinetic analysis on days 1 and 15. RESULTS: Sixteen patients with malignant solid tumors (seven breast, seven colorectal, and two gastric) were enrolled, all of whom were evaluable. Among 4 patients treated with capecitabine 1255 mg/m2 twice daily, one experienced grade 4 hemorrhagic gastric ulcer and one experienced grade 3 skin toxicity. Consequently, this dose was defined as the MTD, and gastrointestinal and cutaneous effects were identified as dose-limiting toxicities. There was no grade 3/4 diarrhea at any dose level. There was also no grade 4 hematologic toxicity at doses below the MTD, and there were no treatment-related deaths. Two patients with breast cancer had partial responses, at capecitabine doses of 502 mg/m2 and 1255 mg/m2, twice daily. Pharmacokinetic data show that high concentrations of doxifluridine (5'-DFUR) occur in tumor cells within 2 h after administration of capecitabine. CONCLUSION: The MTD of continuous oral capecitabine over 6 weeks was 1255 mg/m2 twice daily. Because of the higher occurrence of skin disorders reported in this study with a continuous treatment regimen, an intermittent treatment regimen of 828 mg/m2, administered twice daily for 3 weeks, followed by a 1-week rest period, was recommended for phase II studies. This regimen is being evaluated in phase II studies in Japanese patients with gastric, colorectal, and breast cancers.

Administration, Oral↗