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Dive into the research topics where David M. Ota is active.

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Featured researches published by David M. Ota.


Nature | 2012

Whole Genome Analysis Informs Breast Cancer Response to Aromatase Inhibition

Matthew J. Ellis; Li Ding; Dong Shen; Jingqin Luo; Vera J. Suman; John W. Wallis; Brian A. Van Tine; Jeremy Hoog; Reece J. Goiffon; Theodore C. Goldstein; Sam Ng; Li Lin; Robert Crowder; Jacqueline Snider; Karla V. Ballman; Jason D. Weber; Ken Chen; Daniel C. Koboldt; Cyriac Kandoth; William Schierding; Joshua F. McMichael; Christopher A. Miller; Charles Lu; Christopher C. Harris; Michael D. McLellan; Michael C. Wendl; Katherine DeSchryver; D. Craig Allred; Laura Esserman; Gary Unzeitig

To correlate the variable clinical features of oestrogen-receptor-positive breast cancer with somatic alterations, we studied pretreatment tumour biopsies accrued from patients in two studies of neoadjuvant aromatase inhibitor therapy by massively parallel sequencing and analysis. Eighteen significantly mutated genes were identified, including five genes (RUNX1, CBFB, MYH9, MLL3 and SF3B1) previously linked to haematopoietic disorders. Mutant MAP3K1 was associated with luminal A status, low-grade histology and low proliferation rates, whereas mutant TP53 was associated with the opposite pattern. Moreover, mutant GATA3 correlated with suppression of proliferation upon aromatase inhibitor treatment. Pathway analysis demonstrated that mutations in MAP2K4, a MAP3K1 substrate, produced similar perturbations as MAP3K1 loss. Distinct phenotypes in oestrogen-receptor-positive breast cancer are associated with specific patterns of somatic mutations that map into cellular pathways linked to tumour biology, but most recurrent mutations are relatively infrequent. Prospective clinical trials based on these findings will require comprehensive genome sequencing.


International Journal of Radiation Oncology Biology Physics | 1995

Preoperative infusional chemoradiation therapy for Stage T3 rectal cancer

Tyvin A. Rich; John M. Skibber; Jaffer A. Ajani; Daniel J. Buchholz; Karen R. Cleary; Ronelle A. DuBrow; Bernard Levin; Patrick M. Lynch; Sarkis Meterissian; Leor D. Roubein; David M. Ota

PURPOSE To evaluate preoperative infusional chemoradiation for patients with operable rectal cancer. METHODS AND MATERIALS Preoperative chemoradiation therapy using infusional 5-fluorouracil (5-FU), (300 mg/m2/day) together with daily irradiation (45 Gy/25 fractions/5 weeks) was administered to 77 patients with clinically Stage T3 rectal cancer. Endoscopic ultrasound confirmed the digital rectal exam in 63 patients. Surgery was performed approximately 6 weeks after the completion of chemoradiation therapy and included 25 abdominoperineal resections and 52 anal-sphincter-preserving procedures. RESULTS Posttreatment tumor stages were T1-2, N0 in 35%, T3 N0 in 25%, and T1-3, N1 in 11%; 29% had no evidence of tumor. Local tumor control after chemoradiation was seen in 96% (74 out of 77); 2 patients had recurrent disease at the anastomosis site and were treated successfully with abdominoperineal resection. Overall, pelvic control was obtained in 99% (76 out of 77). The survival after chemoradiation was higher in patients without node involvement than in those having node involvement (p = n.s.). More patients with pathologic complete responses or only microscopic foci survived than did patients who had gross residual tumor (p = 0.07). The actuarial survival rate was 83% at 3 years; the median follow-up was 27 months, with a range of 3 to 68 months. Acute, perioperative, and late complications were not more numerous or more severe with chemoradiation therapy than with traditional radiation therapy (XRT) alone. CONCLUSIONS Excellent treatment response allowed two-thirds of the patients to have an anal-sphincter-sparing procedure. Gross residual disease in the resected specimen indicates a poor prognosis, and therapies specifically targeting these patients may improve survival further.


Gastroenterology | 1994

MUC1 mucin expression as a marker of progression and metastasis of human colorectal carcinoma.

Shoji Nakamori; David M. Ota; Karen R. Cleary; Keiro Shirotani; Tatsuro Irimura

BACKGROUND/AIMS The MUC1 mucin distributes among a variety of epithelial tissues (except the intestinal epithelia) and is often detectable in colorectal carcinoma tissues and cell lines. This study aimed to elucidate whether MUC1 mucin expression correlated to the progression of colorectal carcinomas. METHODS We collected 113 tissue specimens, including primary colorectal carcinoma, normal mucosa, liver metastases, lymph node metastases, and normal livers from 58 patients with colorectal carcinoma. Immunohistochemical staining and Western blotting analysis with mature MUC1 mucin-specific monoclonal antibodies were performed. RESULTS The levels of mature MUC1 mucins were significantly higher in carcinoma tissues than those in normal colonic mucosa (P < 0.001). Furthermore, the levels of mature MUC1 mucins were significantly higher in primary tumors from patients having metastasis or metastatic tumors than in primary tumors from patients without metastasis (P < 0.001). In the primary sites, mature MUC1 mucin levels apparently increased according to progression of the stages (P < 0.001). CONCLUSIONS These results strongly suggest that mature MUC1 mucins become ectopically expressed in colorectal carcinoma progressed to the metastatic stages and that mature MUC1 mucins may be a useful marker for advanced colorectal carcinoma.


Cancer | 1991

Resectable gastric carcinoma. An evaluation of preoperative and postoperative chemotherapy

Jaffer A. Ajani; David M. Ota; J. Milburn Jessup; F. C. Ames; Charles M. McBride; Arthur W. Boddie; Bernard Levin; Diane E. Jackson; Mark S. Roh; David C. Hohn

Patients with locoregional gastric carcinoma often die because of the low rates of curative resection and frequent appearance of distant metastases (mainly peritoneal and hepatic). To evaluate the feasibility of preoperative and postoperative chemotherapy, 25 consecutive previously untreated patients with potentially resectable locoregional gastric carcinoma received two preoperative and three postoperative courses of etoposide, 5‐fluorouracil, and cisplatin (EFP). Ninety‐eight courses (median, five courses; range, two to five courses) were administered. Six patients had major responses to EFP. Eighteen patients (72%) had curative resections, and three specimens (12%) contained only microscopic carcinoma. At a median follow‐up of 25 months, the median survival of 25 patients was 15 months (range, 4 to 32+ months). Peritoneal carcinomatosis was the most common indication of failure. One patient died of postoperative complications, but there were no deaths due to chemotherapy. EFP‐induced toxic reactions were moderate. Preoperative and postoperative chemotherapy for locoregional gastric carcinoma is feasible, and additional studies to develop regimens that could result in 5% to 10% complete pathologic responses may be warranted.


Radiotherapy and Oncology | 1993

Chemoradiation therapy for anal cancer: radiation plus continuous infusion of 5-fluorouracil with or without cisplatin

Tyvin A. Rich; Jaffer A. Ajani; William H. Morrison; David M. Ota; Bernard Levin

Chemoradiation therapy for anal cancer was carried out in 58 patients using low-dose, continuous infusion of 5-fluorouracil (5-FU) with or without continuous infusion of cisplatin (cDDP) and external beam irradiation (chemoXRT). Thirty-nine patients received 5-FU chemoXRT resulting in a local control rate of 50% in those receiving a total dose of < 45 Gy, 73% for those receiving 50-54 Gy, and 83% for those receiving > 60 Gy. The actuarial local control rate at 2 years was 77% after chemoXRT alone; overall local control was 67% at 5 years. In 18 patients receiving 5-FU plus cisplatin with radiation doses of 54-55 Gy, actuarial local control was 85% at 2 years. Fifteen patients failed chemoXRT, 13 of whom had abdominoperineal resection for salvage; the overall local control rate was 93% (54/58). The actuarial survival at 5 years was 81% for the 5-FU chemoXRT group and 94% at 2 years for the 5-FU plus cisplatin chemoXRT group; median follow-up was 54 and 20 months, respectively. Diarrhea and nausea were the most frequent early reactions and were ameliorated by limiting the duration of chemotherapy to 5 days/week and by using XRT techniques to exclude the small bowel from the radiation portal. Serious late radiation complications have not been observed and may be related to XRT fractionation and the use of protracted chemotherapy infusion. The absence of late morbidity coupled with the high local control rate by the use of this chemoXRT program is an area to investigate for improving the therapeutic ratio for the treatment of anal cancers.


International Journal of Radiation Oncology Biology Physics | 1992

Extramammary Paget's disease of the perineal skin : role of radiotherapy

Pelayo C. Besa; Tyvin A. Rich; Luis Delclos; Creighton L. Edwards; David M. Ota; J. Taylor Wharton

We have reviewed our treatment results in 65 patients with extramammary Pagets disease arising in the vulva, perianal area, or scrotum. In 30 patients with primary disease, positive surgical margins were found in 53%, and there was an actuarial local recurrence rate of 40% within 5 years. The median follow-up period for primary extramammary Pagets disease patients treated with surgery alone was 198 months, and none died of this disease. Three patients treated with definitive radiotherapy were without recurrence at 12, 21, and 60 months after 56 Gy of supervoltage x-rays. In 22 patients with extramammary Pagets disease and associated adnexal or rectal adenocarcinoma, nine treated with surgery alone had a 75% local control rate. Three patients treated with surgery and adjuvant radiotherapy all had local control; of two patients treated with radiotherapy alone, one had persistent adenocarcinoma. The median survival for all patients with extramammary Pagets disease and adenocarcinoma was 22 months. We conclude that patients with extramammary Pagets disease have excellent survival but that local recurrence and morbidity from surgery, especially in the elderly, can be high. Radiotherapy greater than 50 Gy as primary treatment for extramammary Pagets disease in those medically unfit for surgery, or as an alternative to further surgery for recurrence after surgery and for anyone wishing to avoid mutilating surgery, is indicated. For those with adenocarcinoma and extramammary Pagets disease, the use of adjuvant postoperative radiotherapy in doses greater than 55 Gy is indicated because of the high risk of local recurrence after surgery alone.


Annals of Surgical Oncology | 2001

Distal Margin Requirements After Preoperative Chemoradiotherapy for Distal Rectal Carcinomas: Are ≤ 1 cm Distal Margins Sufficient?

Boris W. Kuvshinoff; Irfan Maghfoor; Brent W. Miedema; Mark P. Bryer; Steven Westgate; John D. Wilkes; David M. Ota

Background:Sphincter-sparing alternatives to abdominoperineal resection (APR) in the treatment of rectal cancer often are underused out of concern for inadequate distal margins and local failure. The present study addresses whether sphincter-sparing techniques with distal margins ≤ 1 cm adversely influence oncological outcome in patients given preoperative chemoradiotherapy.Methods:Thirty-seven patients with rectal cancer ≤ 8 cm from the anal verge were enrolled in the study. Preoperative external beam radiotherapy (5400 Gy) was administered together with continuous infusion of 5-fluorouracil (300 mg/m2/day). Surgical resection was performed in 36 patients with pathological assessment of tumor response and margins. Patients with sphincter-sparing resection and distal margins > 1 cm or ≤ 1 cm and those who underwent APR were compared.Results:Thirty-six patients completed preoperative chemoradiotherapy, with successful sphincter-preservation in 28 patients. At a median follow-up of 33 months, there were 12 recurrences overall, which included 11 distant failures and four pelvic failures. Disease-free survival (DFS) was not different between those who had an APR compared with sphincter-sparing resection with distal margins ≤ 1 cm. DFS was worse (P < .02) when radial margins were ≤ 3 mm compared with > 3 mm.Conclusions:Sphincter preservation is feasible in more than 75% of patients with tumors ≤ 8 cm from the anal verge after preoperative chemoradiotherapy. Sphincter-sparing surgery with distal margins ≤ 1 cm can be used without adversely influencing local recurrence or DFS. Limited radial margins (≤ 3 mm), however, are associated with increased disease recurrence.


Journal of Clinical Oncology | 1999

Enhanced Staging and All Chemotherapy Preoperatively in Patients with Potentially Resectable Gastric Carcinoma

Jaffer A. Ajani; Paul F. Mansfield; Patrick M. Lynch; Peter W.T. Pisters; Barry W. Feig; Pamela Dumas; Douglas B. Evans; I Raijman; Kristin Hargraves; Stephen Curley; David M. Ota

PURPOSE Patients with local-regional gastric carcinoma have a low rate of curative resection (R0) because of the advanced stage at diagnosis and suboptimal clinical staging. This study was designed to improve clinical staging with the use of laparoscopy and endoscopic ultrasonography (EUS) and to improve R0 resection rates and tolerance by delivering all chemotherapy preoperatively in patients with potentially resectable gastric carcinoma. PATIENTS AND METHODS All patients with histologic proof of localized adenocarcinoma of the stomach underwent a staging laparoscopy before registration. EUS was performed when feasible. The intention was to administer up to five courses of preoperative chemotherapy consisting of fluorouracil (500 mg/m(2)/d as a continuous infusion on days 1 through 5 and as a bolus on days 12 and 19), interferon alfa-2b (3 million units subcutaneously three times a week for 3 weeks), and cisplatin (15 mg/m(2)/d as a bolus on days 1 through 5). After chemotherapy, surgery was attempted to remove the primary and regional lymph nodes. Clinical response and EUS staging were correlated with surgical pathology. The feasibility of this approach, resection rates, patient survival, and patterns of failure also were assessed. RESULTS All 30 patients enrolled were assessed for toxicity, response, and survival. Nineteen men and 11 women were enrolled. The median number of courses delivered per patient was three (range, one to five courses). Fourteen patients (47%) received all five preoperative courses of chemotherapy. The overall clinical response rate was 34%. Twenty-nine patients (97%) underwent attempted resection. Twenty-five (83%) had an R0 resection. Two patients (7%) had no evidence of carcinoma in the surgical specimen, and three had only microscopic carcinoma (>/= 90% necrosis). Posttreatment EUS findings did not correlate well with surgical pathology. The median duration of follow-up was 30 months (range, 5 months to 65+ months). The median survival time for 30 patients, calculated by the Kaplan-Meier method, was 30 months (range, 5 months to 65+ months). There were no cases of grade 4 toxicity. CONCLUSION It is feasible to administer prolonged preoperative therapy in patients with potentially resectable gastric carcinoma. Enhanced staging with laparoscopy and EUS helped in proper selection of patients and better characterization of the stage.


Annals of Surgical Oncology | 1994

Patterns of residual disease after preoperative chemoradiation in ultrasound T3 rectal carcinoma

Sarkis Meterissian; John M. Skibber; Tyvin A. Rich; Leor D. Roubein; Jaffer A. Ajani; Karen R. Cleary; David M. Ota

AbstractBackground: Rectal carcinoma tends to recur locally, with invasion of adjacent organs and significant pelvic pain. Both radiation therapy alone and combined chemoradiation have been used in an attempt to decrease the local recurrence rate and thereby improve survival. Although preoperative chemoradiation can clinically downstage rectal tumors, the pathologic extent of the residual disease has not been studied. Methods: Thirty-seven patients with T3 rectal cancer diagnosed by transrectal ultrasonography (uT3) received 45 Gy with continuous infusion 5-fluorouracil (300 mg/m2/day). Proctoscopy with mucosal/submucosal biopsy was performed in patients (16 of 37) posttreatment and before definitive surgery. Results: Microscopic evaluation of the 37 resected specimens showed a 30% (11 patients) pathologic complete remission rate. The pattern of residual disease in the remaining 26 patients showed that nine (25%) had microscopic residual tumor without evidence of mucosal involvement. Of the 14 patients with a negative proctoscopic evaluation and biopsy only, five (36%) had no residual tumor on final pathology. Conclusions: After chemoradiation, the pathologic presentation of rectal cancer may be altered, making endoscopic procedures and mucosal/submucosal biopsies unreliable in detection of residual disease. Despite the relatively good pathologic complete remission rate noted in this study, all patients undergoing chemoradiation for uT3 rectal carcinomas need definitive surgical resection to confirm a complete clinical remission.


American Journal of Surgery | 1998

Clinical, pathologic, and economic parameters of laparoscopic colon resection for cancer

Michael Bouvet; Paul F. Mansfield; John M. Skibber; Steven A. Curley; Lee M. Ellis; Geoffrey G. Giacco; Alice Madary; David M. Ota; Barry W. Feig

BACKGROUND The appropriateness of laparoscopic colon resection (LCR) as treatment for malignancy has been questioned. METHODS From 1992 to 1997, 91 patients were entered into a prospective study of LCR for cancer. Clinical, pathologic, and economic parameters of LCR were compared in a cohort of patients matched for age, tumor stage, and type of colectomy who underwent open colon resection (OCR) during the same time period. RESULTS With a median follow-up of 26 months, there were no significant differences in survival rate for patients in the LCR, converted colon resection, and OCR groups. There were no port-site recurrences and the number of lymph nodes harvested was similar among the procedures. Hospital stay was significantly shorter if laparoscopic resection was successful. Total hospital costs were similar for LCR and OCR; however, the costs were significantly higher for converted colon resection. CONCLUSIONS LCR is a sound oncologic procedure that can be performed with costs similar to OCR.

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Jaffer A. Ajani

University of Texas MD Anderson Cancer Center

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Karen R. Cleary

University of Texas MD Anderson Cancer Center

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Kenji Nishioka

University of Texas MD Anderson Cancer Center

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Heidi Nelson

University of Rochester

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V. Bruce Grossie

University of Texas MD Anderson Cancer Center

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Tatsuro Irimura

University of Texas at Austin

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Tatsuro Irimura

University of Texas at Austin

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John M. Skibber

University of Texas MD Anderson Cancer Center

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