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Dive into the research topics where George A. Omura is active.

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Featured researches published by George A. Omura.


Journal of Clinical Oncology | 1991

Long-term follow-up and prognostic factor analysis in advanced ovarian carcinoma: the Gynecologic Oncology Group experience.

George A. Omura; Mark F. Brady; Howard D. Homesley; Edgardo Yordan; Francis J. Major; Herbert J. Buchsbaum; Robert C. Park

Long-term follow-up was obtained on 726 women with advanced ovarian carcinoma (suboptimal stage III and stage IV) who had received primary chemotherapy on two Gynecologic Oncology Group (GOG) protocols between 1976 and 1982. The first study compared melphalan alone versus melphalan plus hexamethylmelamine versus cyclophosphamide plus doxorubicin (CA). The second study evaluated the same CA regimen with or without cisplatin. Eligibility for the two studies was the same. At last contact, 76 patients were alive. In a multivariate analysis, cell type other than clear cell or mucinous, cisplatin-based treatment, good performance status, younger age, lower stage, clinically nonmeasurable disease, smaller residual tumor volume, and absence of ascites were favorable characteristics for overall survival (P less than .05). Second-look laparotomy was negative significantly more often among those with endometrioid tumors; there were no negative second-look laparotomies among those with mucinous or clear cell tumors. There were 30 patients with suboptimal stage III disease who had a negative second-look laparotomy; 18 (60%) have experienced recurrence, and 13 (43%) have died. Although cisplatin treatment was beneficial, new treatments are clearly needed.


Journal of Clinical Oncology | 1989

Evaluation of optimal duration of chemotherapy in favorable-prognosis disseminated germ cell tumors: a Southeastern Cancer Study Group protocol.

Lawrence H. Einhorn; Stephen D. Williams; Patrick J. Loehrer; Birch R; R Drasga; George A. Omura; F A Greco

Four courses of PVP16B (cisplatin plus etoposide [VP-16] plus bleomycin) has been standard chemotherapy for disseminated germ cell tumors at Indiana University and the Southeastern Cancer Study Group (SECSG) since 1984. We began a random prospective phase III study in patients with favorable-prognosis (minimal and moderate extent) disseminated germ cell tumors comparing four courses of PVP16B over 12 weeks to the identical dose PVP16B administered in three courses over 9 weeks. The categories of minimal and moderate disease constitute approximately two thirds of all disseminated germ cell tumors that require chemotherapy. One hundred eighty-four patients entered this trial, and all patients have a minimal follow-up of 1 year. Overall, 106 of 107 (99%) minimal extent and 73 of 77 moderate patients (95%) achieved an initial disease-free status (NED), confirming the favorable prognostic categories. Eighty-six of 88 patients (98%) randomized to three courses and 93 of 96 randomized to four courses (97%) of PVP16B achieved disease-free status. There have been ten relapses (5%), with five on each arm. Currently, 81 of 88 (92%) and 88 of 96 (92%) patients randomized to three v four courses of PVP16B are continuously disease-free. This study confirms the high cure rate with PVP16B in favorable-prognosis germ cell tumors. The deletion of the fourth course of PVP16B significantly reduces the toxicity, cost, and inconvenience of this curative regimen. We conclude that three courses of PVP16B is the preferred regimen for favorable-prognosis germ cell tumors.


Journal of Clinical Oncology | 1985

A randomized clinical trial of adjuvant adriamycin in uterine sarcomas: a Gynecologic Oncology Group Study.

George A. Omura; Frank Major; Samuel Lifshitz; Clarence E. Ehrlich; Charles Mangan; Jackson B. Beecham; Robert C. Park; Steven G. Silverberg

After hysterectomy, 156 evaluable patients with stage I (limited to the corpus) or stage II (limited to the corpus and cervix) uterine sarcomas were randomly assigned to adjuvant chemotherapy with Adriamycin (Adria Laboratories, Columbus, Ohio) for six months or to no further treatment. Pelvic irradiation (external or intracavitary) was optional before randomization. Of 75 patients receiving Adriamycin, 31 have suffered recurrences compared with 43 of 81 receiving no adjuvant chemotherapy. This difference is not statistically significant. Moreover, there is no difference in progression-free interval or survival. The optional radiotherapy did not influence the outcome although there was a suggestion that vaginal recurrence was decreased by pelvic radiotherapy. The recurrence rates in specific cell types (leiomyosarcoma, homologous mixed mesodermal sarcoma, or heterologous mixed mesodermal sarcoma) were not significantly different although the pattern of recurrence differed, with pulmonary metastases being more common in leiomyosarcoma and extrapulmonary recurrence being more common in mixed mesodermal sarcoma. The outcome with respect to chemotherapy was not altered even after adjusting for maldistribution of cases. Thus, we could not show a benefit for this dose schedule of Adriamycin as adjuvant treatment for uterine sarcomas.


Journal of Clinical Oncology | 1989

Randomized trial of cyclophosphamide plus cisplatin with or without doxorubicin in ovarian carcinoma: a Gynecologic Oncology Group Study.

George A. Omura; Brian N. Bundy; Jonathan S. Berek; Stephen L. Curry; Gregorio Delgado; Rodrigue Mortel

A randomized clinical trial was conducted in women with stage III ovarian carcinoma (less than or equal to 1 cm residual lesions), using cyclophosphamide plus cisplatin (CP) with or without doxorubicin. There were 349 evaluable patients, of whom 176 received CP while 173 patients received CP plus doxorubicin (CAP). Hematologic toxicity was almost identical. There was no significant difference in progression-free interval (PFI) (median, 22.7 months and 24.6 months), frequency of negative second-look laparotomy (30.2% and 32.8%), or survival (median, 31.2 months and 38.9 months) between CP and CAP, respectively. Thus, doxorubicin in the dose schedule employed does not improve combination chemotherapy of optimal stage III ovarian carcinoma. Several other findings, independent of treatment arm, were of interest. There was a significant difference in PFI and survival by residual disease category (yes v no) and by grade of differentiation (1 v 2 + 3). In multivariate analysis, age, residual disease at entry, cell type (clear cell carcinoma), and time from surgery to initiation of chemotherapy were significant predictors of survival. There was no difference in outcome comparing those who refused second-look with those who had a second-look.


Journal of Clinical Oncology | 1988

Cisplatin plus etoposide consolidation following cyclophosphamide, doxorubicin, and vincristine in limited small-cell lung cancer.

Lawrence H. Einhorn; Jeffrey Crawford; R Birch; George A. Omura; D. H. Johnson; F A Greco

From June 1982 through October 1985, the Southeastern Cancer Study Group randomized patients with limited small-cell lung cancer (SCLC) to cyclophosphamide plus doxorubicin (Adriamycin, Adria Laboratories, Columbus, OH) plus vincristine (CAV) for six cycles v CAV plus concomitant thoracic irradiation as induction therapy. Patients achieving either a complete or partial response and remaining in remission after completion of induction therapy were subsequently randomized to consolidation chemotherapy consisting of cisplatin 20 mg/m2 X 4 plus etoposide (VP-16) 100 mg/m2 X 4 every 4 weeks for two courses v no further therapy. There were 160 patients entered on the consolidation phase and 148 were fully evaluable. The median survival for patients randomized to cisplatin plus VP-16 (PVP16) from start of CAV chemotherapy was 97.7 weeks, compared with 68 weeks for the no-consolidation arm (P = .0094). PVP16 consolidation also significantly increased the duration of remission, with median durations of 49 weeks v 28 weeks (P = .0008). The median durations for partial remission were 41 weeks v 23 weeks (P = .013), and for complete remission, 52 weeks v 30.5 weeks (P = .0091). Furthermore, 18 patients on PVP16 consolidation remain in a continuous complete remission for 12+ months and 13 of these are continuously disease free 2+ years. Eight patients randomized to no consolidation remain in a continuous complete remission, with only four patients disease free 2+ years. PVP16 consolidation has significantly improved the duration of remission and overall survival and appears capable of improving the cure rate in limited SCLC.


Journal of Clinical Oncology | 2003

Phase III Trial of Paclitaxel at Two Dose Levels, the Higher Dose Accompanied by Filgrastim at Two Dose Levels in Platinum-Pretreated Epithelial Ovarian Cancer: An Intergroup Study

George A. Omura; Mark F. Brady; Katherine Y. Look; Hervy E. Averette; James E. Delmore; Harry J. Long; Scott Wadler; Gregory Spiegel; Susan G. Arbuck

PURPOSEnTo determine if increasing the dose of paclitaxel increases the probability of clinical response, progression-free survival, or overall survival in women who have persistent or recurrent ovarian cancer, and whether doubling the dose of prophylactic filgrastim accompanying the higher paclitaxel dose decreases the frequency of neutropenic fever.nnnPATIENTS AND METHODSnConsenting patients with persistent, recurrent, or progressing ovarian cancer, despite first-line platinum therapy (but no prior taxane), were randomly assigned to paclitaxel 135 mg/m2, 175 mg/m2, or 250 mg/m2 over 24 hours every 3 weeks. Patients receiving paclitaxel 250 mg/m2 were also randomly assigned to 5 or 10 microg/kg of filgrastim per day subcutaneously.nnnRESULTSnAccession to the paclitaxel 135-mg/m2 arm was closed early. Among the 271 patients on the other regimens with measurable disease, partial and complete response on paclitaxel 250 mg/m2 (36%) was significantly higher than on 175 mg/m2 (27%, P =.027). This difference was more evident among patients who never responded to prior platinum. However, progression-free and overall survival results were similar. The median durations of overall survival were 13.1 and 12.3 months for paclitaxel 175 mg/m2 and 250 mg/m2, respectively. Thrombocytopenia, neuropathy, and myalgia were greater with paclitaxel 250 mg/m2 (P <.05). The incidence of neutropenic fever after the first cycle of paclitaxel 250 mg/m2 was 19% and 18% on the 5-microg/kg and 10-microg/kg filgrastim dose, respectively (22% for paclitaxel 175 mg/m2 without filgrastim).nnnCONCLUSIONnPaclitaxel exhibits a dose effect with regard to response rate, but there is more toxicity and no survival benefit to justify paclitaxel 250 mg/m2 plus filgrastim. Doubling the filgrastim dose from 5 to 10 microg/kg did not reduce the probability of neutropenic fever after high-dose paclitaxel.


Journal of Clinical Oncology | 1989

Ifosfamide Plus Doxorubicin in Metastatic Adult Sarcomas: A Multi-Institutional Phase II Trial

Patrick J. Loehrer; George W. Sledge; Claude Nicaise; Jeffrey Usakewicz; John D. Hainsworth; Orlando J. Martelo; George A. Omura; Thomas J. Braun

Between April 1986 and March 1987, 42 patients with advanced sarcoma were entered in this multi-institutional trial evaluating ifosfamide plus doxorubicin. The majority of patients had leiomyosarcoma and malignant fibrous histiocytoma although two patients with sarcomas of osseous origin were included. Doxorubicin was administered at a dosage of 60 mg/m2 by continuous push and ifosfamide 5.0 g/m2 by continuous infusion over 24 hours with mesna (7.5 g2 over 36 hours) with courses repeated every 3 weeks until progression, toxicity cumulative doxorubicin dosage of 450 mg/m2. Overall, 15 (36%) patients demonstrated objective remissions including three complete and 12 partial remissions (95% confidence limits, 21.5% to 52.0%). The median duration of remission was 7.0 months and the median survival time for all eligible patients was 8.0 months. Toxicity was predominantly hematologic with the median leukocyte nadir being 1,300 per microliter of blood and documented sepsis in six patients. These data support activity for ifosfamide plus doxorubicin in patients with advanced sarcoma, but the actual contribution of ifosfamide needs to be evaluated through prospective randomized trials which are currently underway.


Journal of Clinical Oncology | 1985

Phase III study of BCOP v CHOP in unfavorable categories of malignant lymphoma: a Southeastern Cancer Study Group trial.

Richard A. Gams; Marilyn Rainey; Maurice Dandy; Alfred A. Bartolucci; Harold R. Silberman; George A. Omura

A total of 296 evaluable patients with unfavorable categories of malignant lymphoma were randomly assigned treatment with cyclophosphamide, vincristine, and prednisone plus BCNU (BCOP) or doxorubicin (CHOP). In diffuse histiocytic (DH) lymphoma, CHOP produced superior complete (54% v 34%) and total (70% v 46%) response rates. Among the responders to either therapy, no differences were seen in duration of response or survival times. Median duration of response has not been reached with follow-up in excess of 50 months. In categories of lymphoma other than DH (including small-cell, mixed, and nodular histiocytic lymphomas), complete (27% v 29%) and total (48% v 54%) responses were similar for BCOP and CHOP, as were durations of response and survival. These data suggest that BCOP and CHOP are equivalent regimens for other categories of malignant lymphomas. CHOP appears preferable for diffuse large-cell categories, since it resulted in greater overall survival in patients with DH lymphoma; this was due to a significantly greater response rate, since patients with DH lymphoma who did respond to BCOP maintained their response and survived as long as did the CHOP responders.


Cancer | 1986

Treatment of chronic lymphocytic leukemia using chlorambucil and prednisone with or without cycle-active consolidation chemotherapy .A southeastern cancer study group trial

James W. Keller; William H. Knospe; Marilyn Raney; Charles M. Huguley; Lorraine Johnson; Alfred A. Bartolucci; George A. Omura

Patients with untreated chronic lymphocytic leukemia (CLL) received protocol treatment with 6 months of chlorambucil (CB) (30 mg/M2) and prednisone (P) (80 mg/d × 5) every 2 weeks. Complete and partial responders (CR, PR) were then randomized to consolidation with six more courses of CB and P or to four courses of cytosine arabinoside (25 mg/M2 every 12 hours × 8, subcutaneously) and cyclophosphamide (25 mg/M2 every 12 hours × 8, orally) every three weeks. Of the 178 eligible patients entered, 138 (78%) were evaluable for induction therapy which produced a 22% hematologic CR and an overall response rate (CR + PR) of 74%. Eighty‐two patients received adequate consolidation, at the end of which 43 were in CR. No difference was seen in response or survival between the two consolidation treatments. Responders had longer survival than nonresponders (P = 0.0001) even when a 6‐month ‘guarantee time’ was excluded, but there was no survival difference between CR and PR. Thus, intermittent CB and P is a well‐tolerated, useful therapy for CLL but the addition of cyclophosphamide and cytosine arabinoside does not improve results.


Journal of Clinical Oncology | 1984

Randomized phase III comparison of three doxorubicin-based chemotherapy regimens in advanced non-small cell lung cancer: a Southeastern Cancer Study Group trial.

Francisco Robert; George A. Omura; Robert Birch; Stephen Krauss; Robert Oldham

From 1978 to 1981, 537 patients with advanced non-small cell lung cancer were randomly assigned to three regimens containing cyclophosphamide and doxorubicin alone or in combination with methotrexate or cisplatin. Eligible patients had measurable disease and had no prior exposure to chemotherapy. Of the patients entered on the study, 505 were evaluable for toxicity and 488 were evaluable for response. The overall response rate (complete and partial responses) was only 9%. Response rates did not vary significantly with respect to treatment regimen, histologic subtypes, extent of disease, or performance status. There was no survival advantage for any regimen. The major toxicities were myelosuppression and nausea-vomiting. These doxorubicin-based chemotherapy regimens produced disappointing results in patients with advanced non-small cell lung cancer. A search for more active antitumor agents in lung cancer is necessary.

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Alfred A. Bartolucci

University of Alabama at Birmingham

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Marilyn Raney

University of Alabama at Birmingham

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Mark F. Brady

Roswell Park Cancer Institute

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Robert C. Park

Walter Reed Army Medical Center

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