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Featured researches published by Victor Hamasaki.


Journal of Clinical Oncology | 1997

High-dose chemotherapy and stem-cell rescue in the treatment of high-risk breast cancer: prognostic indicators of progression-free and overall survival.

George Somlo; James H. Doroshow; Stephen J. Forman; Tamara Odom-Maryon; Jennifer Lee; Warren Chow; Victor Hamasaki; Lucille Leong; Robert J. Morgan; Kim Margolin; James Raschko; Stephen Shibata; Merry Tetef; Yun Yen; Jean F. Simpson; Arturo Molina

PURPOSE To examine the predictive value of tumor- and treatment-specific prognostic indicators of relapse-free survival (RFS) and overall survival (OS) in patients with high-risk breast cancer (HRBC) treated with high-dose chemotherapy (HDCT) and stem-cell rescue. PATIENTS AND METHODS Between June 1989 and September 1994, 114 patients with HRBC (stage II with > or = 10 axillary lymph nodes involved, stage IIIA, and stage IIIB inflammatory carcinoma) received adjuvant chemotherapy followed by HDCT with etoposide, cyclophosphamide, and either doxorubicin (CAVP) or cisplatin (CCVP). Variables analyzed included stage, tumor size, number of axillary nodes involved, grade and receptor status, and types of adjuvant chemotherapy and radiation therapy and HDCT. RESULTS With a median follow-up time of 46 months (range, 23 to 93), Kaplan-Meier estimates of 3.5-year OS for stage II, IIIA, and IIIB HRBC are 82% (95% confidence interval [CI], 67% to 97%), 79% (95% CI, 67% to 91%), and 72% (95% CI, 53% to 91%); RFS estimates are 71% (95% CI, 56% to 85%), 57% (95% CI, 43% to 72%), and 50% (95% CI, 29% to 71%) irrespective of the HDCT regimen. In univariate analysis, the risk of relapse was lower for patients with progesterone receptor (PR)-positive tumors (risk ratio [RR], 0.43; 95% CI, 0.22 to 0.81; P = .01) and higher for patients with inflammatory carcinoma (RR, 2.20; 95% CI, 1.02 to 4.76; P = .05). OS was better for patients with PR (RR, 0.16; 95% CI, 0.05 to 0.55; P = .003) and estrogen receptor (ER)-positive tumors (RR, 0.42; 95% CI, 0.17 to 1.02; P = .05); OS was worse for patients with high-grade primary tumors (RR, 4.08; 95% CI, 1.21-13.7; P = .02). In multivariate analysis, PR positivity was associated with improved RFS (P = .01) and OS (P = .001). CONCLUSION HDCT in selected patients with HRBC is safe and warrants further evaluation. Patients with receptor-negative, high-grade, or inflammatory tumors require improvement in their therapeutic options. Better assessment of the role of HDCT awaits completion of ongoing randomized trials.


Journal of Clinical Oncology | 1996

Treatment of germ cell cancer with two cycles of high-dose ifosfamide, carboplatin, and etoposide with autologous stem-cell support.

Kim Margolin; James H. Doroshow; Chul Ahn; Victor Hamasaki; Lucille Leong; Robert J. Morgan; James Raschko; Stephen Shibata; George Somlo; Merry Tetef

PURPOSE To evaluate the activity of two cycles of high-dose ifosfamide, carboplatin, and etoposide (ICE) with autologous hematopoietic progenitor cell support (aHPCS) in patients with poor-prognosis, chemotherapeutically sensitive germ cell cancer. PATIENTS AND METHODS Twenty patients with germ cell tumor who had persistent disease or relapse from standard-risk or high-risk presentation were entered on this pilot study. The entry criteria included relapsed gonadal and extragonadal germ cell cancer unlikely to be cured by standard salvage therapy but without proven refractoriness to chemotherapy. Treatment consisted of two cycles of ICE chemotherapy with mesna uroprotection and aHPCS. On the first cycle, ifosfamide (IFX), 2 gm/m2; carboplatin, 400 mg/m2; and etoposide, 20 mg/kg, were administered on days -6, -5, and -4. On the second cycle, the doses and schedule of carboplatin and etoposide were identical, and patients with normal renal function received additional IFX, 2 g/m2 on day -3 and 1 g/ m2 on day -2. Mesna, 600 mg/m2 every 6 hours, was given until 24 hours following the final dose of IFX on each cycle, and autologous bone marrow and/or peripheral stem-cells were infused on day 0. RESULTS All twenty patients are assessable for toxicity and current disease status. Two patients received only one cycle of therapy, one because of the development of active hepatitis C following cycle 1, and one because of renal insufficiency. No patient died as a result of protocol therapy, and no patient developed debilitating peripheral neuropathy, symptomatic hearing loss, or severe renal insufficiency requiring dialysis. The median time to recovery of > or = 500 neutrophils/microL and platelets > or = 50,000/microL was day +11 and day +15, respectively. The median maximum creatinine was 1.6 mg/dL on each treatment cycle, and there was no other significant organ toxicity. With a median follow-up of 45 months, nine patients are alive and disease-free following protocol chemotherapy. One patient with embryonal cancer developed progressive pulmonary metastases 3 months after completing high-dose therapy, underwent complete resection of lung metastases, and remains disease-free at 63+ months. Eight patients are continuously disease free at 23+ to 70+ months after protocol therapy. Eleven patients died of progressive disease between 4 and 23 months following completion of treatment. CONCLUSION These results compare favorably to other studies in similarly selected patients undergoing salvage therapy with one or two cycles of chemotherapy containing high-dose carboplatin and etoposide with or without cyclophosphamide (CTX) or IFX. The excellent safety and tolerability profile of this regimen and its encouraging activity in poor-prognosis patients make it worthy of further study as part of initial therapy in randomized protocols for high-risk disease and early in the treatment of relapsed germ cell cancer.


Cancer Chemotherapy and Pharmacology | 1996

Pharmacokinetics and toxicity of 120-hour continuous-infusion hydroxyurea in patients with advanced solid tumors

Edward M. Newman; Mary Carroll; Steven A. Akman; Warren Chow; Paul Coluzzi; Victor Hamasaki; Lucille Leong; Kim Margolin; Robert J. Morgan; James Raschko; Stephen Shibata; George Somlo; Merry Tetef; Yun Yen; Chul Ahn; James H. Doroshow

Abstract A group of 18 patients with advanced cancer were entered on a phase I study of a 120-h continuous intravenous infusion of hydroxyurea. The dose of hydroxyurea was escalated in cohorts of patients from 1 to 2 to 3.2 g/m2 per day. The primary dose-limiting toxicity was neutropenia, often accompanied by leukopenia, thrombocytopenia and generalized skin rash. Prophylactic treatment of patients with dexamethasone and diphenhydramine hydrochloride prevented the skin rash, but not the hematopoietic toxicities. The pharmacokinetics of hydroxyurea were studied in all patients. The steady-state concentrations of hydroxyurea were linearly correlated with the dose (R2 = 0.71, n = 18, P<0.0001). The mean±SE concentrations were 93±16, 230±6 and 302±27 μM at 1, 2 and 3.2 g/m2 per day, respectively. The mean±SE renal and nonrenal clearances of hydroxyurea were 2.14±0.18 and 3.39±0.28 l/h per m2 (n = 16), neither of which correlated with the dose. The concentration of hydroxyurea in plasma decayed monoexponentially with a mean±SE half-life of 3.25±0.18 h (n = 17). The steady-state concentration of hydroxyurea was >200 μM in all nine patients treated at 2 g/m2 per day, a dose which was well tolerated for 5 days. We recommend this dose for phase II trials in combination with other antineoplastic agents.


Cancer Chemotherapy and Pharmacology | 2000

A phase I study of carboplatin and etoposide administered in conjunction with dipyridamole, prochlorperazine and cyclosporine A.

James Raschko; Timothy W. Synold; Warren Chow; Paul Coluzzi; Victor Hamasaki; Lucille Leong; Kim Margolin; Robert J. Morgan; Stephen Shibata; George Somlo; Merry Tetef; Yun Yen; Anna Ter Veer; James H. Doroshow

Purpose: In recognition of the variety of available chemotherapeutic modulating agents and their potential to enhance the efficacy of platinum-based therapy, we embarked upon a phase I study to investigate the feasibility of combining fixed doses of carboplatinum (CBDCA) and etoposide (VP-16) with 24-h concurrent infusions of dipyridamole (DP), prochlorperazine (PCZ) and cyclosporine A (CSA) administered in escalating doses. Methods: Patients received intravenous VP-16 (200 mg/m2) and CBDCA (300 mg/m2), each over 30 min, starting at hour 6 of the modulator infusions. Resistance modulators were escalated sequentially to determine their respective maximally tolerated doses (MTDs). The pharmacokinetics (PK) of VP-16, CBDCA, and the three drug resistance (DR) modifiers were studied in eight patients. Results: A total of 59 patients were entered on study. The MTD was established at DP 5 mg/kg per day, PCZ 24 mg/h, and CSA 9.5 mg/kg per day. Dose-limiting toxicities included hypotension and severe sedation, presumably related to PCZ. No objective responses were seen. PK studies were performed when PCZ and DP doses were 24 mg/h and 3.3 mg/kg, and the CSA dose was either 8.5 mg/kg (five patients) or 9.5 mg/kg (three patients). The median clearance of VP-16 was 0.96 l/h per m2 (range 0.8–1.5 l/h per m2), which is lower than for VP-16 alone and similar to previously reported effects of CSA on VP-16 elimination. The median measured CBDCA AUC was 3.0 mg/ml · min (range 2.4–4.8 mg/ml · min). CBDCA AUC predicted by the Calvert formula using measured creatinine clearance underestimated the actual AUC in seven of the eight patients, in one case by as much as twofold. The median end of infusion PCZ and total DP plasma concentrations were 1.2 μM (range 0.5–2.2 μM) and 4.4 μM (range 1.3–5.9 μM), respectively, consistent with in vitro resistance modulatory levels. However, free DP was only 0.02 μM (range 0.004–0.04 μM). The median CSA level at 24 h of 1450 μg/l (range 1075–1640 μg/l) is in agreement with concentrations required for partial DR reversal in vitro, although it is much lower than levels achieved in our previous phase I study of CBDCA + CSA alone using similar doses of CSA. The CSA dose on the current trial was escalated beyond the MTD for the previous phase I study, suggesting that there may be an interaction between CSA and one of the other modulators. Conclusion: These results demonstrate that in vitro DR- reversing levels of two of the three agents used in this study can be achieved in vivo, and that this combination of DR modulators has significant effects on the pharmacokinetics of VP-16.


Current Opinion in Oncology | 1992

Chemotherapy in head and neck cancer

Victor Hamasaki; Everett E. Vokes

The role of chemotherapy in the management of patients with head and neck cancer continues to evolve. Single-agent methotrexate or cisplatin, or the combination of cisplatin and infusional fluorouracil can be considered standard therapy for patients with recurrent disease. Neoadjuvant chemotherapy is being actively pursued. Although enhanced survival has not yet been demonstrated, the goal of organ preservation has been achieved for patients with laryngeal cancer. Because of the high incidence of locoregional failure, concomitant chemoradiotherapy is also under investigation. This treatment approach has already been suggested to result in prolonged survival in randomized studies and holds promise for the future.


Medical Oncology | 1995

Interferons and other cytokines in head and neck cancer

Victor Hamasaki; Everett E. Vokes

The use of cytokines in head and neck cancer is increasingly under investigation. Clinical trials have tested the interferons, interleukin-2 and other cytokines as single agents and in various combinations. The addition of interferon to the cisplatin and 5-fluorouracil (5-FU) regimens (with and without leucovorin) has been explored. A randomized international trial comparing cisplatin and 5-FU with cisplatin, 5-FU and interferon-α 2b is in progress.


Bone Marrow Transplantation | 2001

Phase II trial of high-dose intravenous doxorubicin, etoposide, and cyclophosphamide with autologous stem cell support in patients with residual or responding recurrent ovarian cancer

Robert J. Morgan; James H. Doroshow; Lucille Leong; Jeffrey Schriber; Stephen Shibata; Stephen J. Forman; Victor Hamasaki; Kim Margolin; George Somlo; Joseph Alvarnas; Mark McNamara; Jeffrey Longmate; James Raschko; Warren Chow; Steven A. Vasilev; Kathryn F. McGonigle; Yun Yen

This study was performed in order to evaluate the toxicities, progression-free and overall survival of patients with responsive residual or recurrent ovarian cancer treated with high-dose chemotherapy. Twenty-seven patients were treated. Doxorubicin, 165 mg/m2 over 96 h (days −12 to −8), etoposide 700 mg/m2 every day ×3 (days −6 to −4), and cyclophosphamide 4.2 g/m2 on d −3 was followed by stem cells and granulocyte colony-stimulating factor. The median days of granulocyte count <500/μl was 14 (range 10–42) and platelets <20 000/μl was 13 (range 2–80). Median numbers of red cell and platelet transfusions were 15 (5–16) and 14 (4–103). Toxicity included mucositis requiring narcotic analgesia in all patients. Asymptomatic decreases in ejection fraction to values <50% were observed in four patients. No clinical congestive heart failure was observed. One death due to sepsis was observed. Median progression-free survival is 7.5 months (1.0–56 months); five patients remain alive, two of whom remain progression-free at 19.5 and 24.5 months post transplant. Median overall survival is 14.0 months (1–68 months). We conclude that high-dose anthracyclines may be safely administered to ovarian cancer patients. The short overall and progression-free survivals observed in our population suggest that this combination is not optimal. Bone Marrow Transplantation (2001) 28, 859–863.


Current Opinion in Oncology | 1993

Chemotherapy and combined modality therapy in head and neck cancer

Victor Hamasaki; Everett E. Vokes

Chemotherapy for head and neck cancer is being actively investigated. Trials of cisplatin, infusional fluorouracil, and other new agents highlight the need for better therapies for patients with recurrent disease. Induction chemotherapy, concomitant chemoradiotherapy, and rapid-sequence combined therapy have been shown to be feasible treatments with encouraging results. Rapidly alternating chemoradiotherapy has been shown to result in a survival benefit compared with radiotherapy alone. Biologic therapy, including interferon and interleukin-2, also merits future evaluation in clinical trials.


Advances in Experimental Medicine and Biology | 1993

Fluorouracil and Leucovorin in Advanced Breast Cancer

James H. Doroshow; Kim Margolin; Lucille Leong; Steven A. Akman; Robert J. Morgan; James Raschko; George Somlo; Victor Hamasaki; Eleanor Womack; Edward M. Newman; Chul Ahn

It is clear from the studies summarized above that the combination of leucovorin and 5-FU can salvage 15–20% of heavily-pretreated patients with advanced breast cancer. In previously-untreated patients, the combination generates objective responses in over one third of women with a very modest and acceptable toxicity profile. It is also clear that the addition of mitoxantrone or cisplatin to 5-FU and leucovorin produces very effective regimens, that, at least in the case of the platinum combination, may be quite active in patients who have failed therapy with an anthracycline. All of these recently-completed trials, suggest that studies currently in progress aimed at improving the biochemical modulation of the fluoropyrimidines have real promise for enhancing the therapy of patients with advanced breast cancer further.


Cancer Chemotherapy and Pharmacology | 2003

Phase I study of cisdiamminedichloroplatinum in combination with azidothymidine in the treatment of patients with advanced malignancies

Robert J. Morgan; Edward M. Newman; Lawrence C. Sowers; Kevin J. Scanlon; Jonathan Harrison; Steven A. Akman; Lucille Leong; Kim Margolin; Joyce C. Niland; James Raschko; George Somlo; Mary Carroll; Warren Chow; Merry Tetef; Victor Hamasaki; Yun Yen; James H. Doroshow

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James Raschko

City of Hope National Medical Center

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Lucille Leong

City of Hope National Medical Center

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George Somlo

City of Hope National Medical Center

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James H. Doroshow

City of Hope National Medical Center

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Kim Margolin

City of Hope National Medical Center

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Robert J. Morgan

City of Hope National Medical Center

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Merry Tetef

City of Hope National Medical Center

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Stephen Shibata

City of Hope National Medical Center

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Warren Chow

City of Hope National Medical Center

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Yun Yen

Taipei Medical University

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