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Dive into the research topics where Douglas S. Tyler is active.

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Featured researches published by Douglas S. Tyler.


Gastrointestinal Endoscopy | 2003

Lower frequency of peritoneal carcinomatosis in patients with pancreatic cancer diagnosed by EUS-guided FNA vs. percutaneous FNA.

Carlos G. Micames; Paul S. Jowell; Rebekah R. White; Erik K. Paulson; Rendon C. Nelson; Michael A. Morse; Herbert Hurwitz; Theodore N. Pappas; Douglas S. Tyler; Kevin McGrath

BACKGROUND Studies have suggested an increased risk of peritoneal seeding in patients with pancreatic cancer diagnosed by percutaneous FNA. EUS-FNA is an alternate method of diagnosis. The aim of this study was to compare the frequency of peritoneal carcinomatosis as a treatment failure pattern in patients with pancreatic cancer diagnosed by EUS-FNA vs. percutaneous FNA. METHODS Retrospective review of patients with non-metastatic pancreatic cancer identified 46 patients in whom the diagnosis was made by EUS-FNA and 43 with the diagnosis established by percutaneous FNA. All had neoadjuvant chemoradiation. Patients underwent restaging CT after completion of therapy, followed by attempted surgical resection if there was no evidence of disease progression. RESULTS There were no significant differences in tumor characteristics between the two study groups. In the EUS-FNA group, one patient had developed peritoneal carcinomatosis compared with 7 in the percutaneous FNA group (2.2% vs. 16.3%; p<0.025). No patient with a potentially resectable tumor in the EUS-FNA group had developed peritoneal carcinomatosis. CONCLUSIONS Peritoneal carcinomatosis may occur more frequently in patients who undergo percutaneous FNA compared with those who have EUS-FNA for the diagnosis of pancreatic cancer. A concern for peritoneal seeding of pancreatic cancer via percutaneous FNA is warranted. EUS-guided FNA is recommended as the method of choice for diagnosis in patients with potentially resectable pancreatic cancer.


Annals of Surgery | 1995

Preoperative radiation and chemotherapy in the treatment of adenocarcinoma of the rectum

Ravi S. Chari; Douglas S. Tyler; Mitchell S. Anscher; Linda Russell; Bryan M. Clary; James W. Hathorn; Hilliard F. Seigler

ObjectiveIn this study, the impact of preoperative chemotherapy and radiation on the histopathology of a subgroup of patients with rectal adenocarcinoma was examined. As well, survival, disease-free survival and pelvic recurrence rates were examined, and compared with a concurrent control group. Summary Background DataThe optimal treatment of large rectal carcinomas remains controversial; current therapy usually involves abdominoperineal resection plus postoperative chemoradiation; the combination can be associated with significant postoperative morbidity. In spite of these measures, local recurrences and distant metastases continue as serious problems. MethodsFluorouracil, cisplatin, and 4500 cGy were administered preoperatively over a 5-week period, before definitive surgical resection in 43 patients. In this group of patients, all 43 had biopsyproven lesions >3 cm (median diameter), involving the entire rectal wall (as determined by sigmoidoscopy and computed tomography scan), with no evidence of extrapelvic disease. The patients ranged from 31 to 81 years of age (median 61 years), with a male:female ratio of 3:1. A concurrent control group consisting of 56 patients (median: 62 years, male:female ration of 3:2) with T2 and T3 lesions was used to compare survival, disease-free survival, and pelvic recurrence rates. ResultsThe preoperative chemoradiation therapy was well tolerated, with no major complications. All patients underwent repeat sigmoidoscopy before surgery; none of the lesions progressed while patients underwent therapy, and 22 (51%) were determined to have complete clinical response. At the time of resection, 21 patients (49%) had gross disease, 9 (22%) patients had only residual microscopic disease, and 11 (27%) had sterile specimens. Of the 30 patients with evidence of residual disease, 4 had positive lymph nodes. In follow-up, 39 of the 43 remain alive (median follow-up = 25 months), and only 1 of the 11 patients with complete histologic response developed recurrent disease. Six of the 32 patients with residual disease (2 with positive nodes) have developed metastatic disease in follow-up (median time to diagnosis 10 months, range 3–15 months). Three of these patients with metastases have died (median survival after diagnosis of


Annals of Surgical Oncology | 2001

Neoadjuvant chemoradiation for localized adenocarcinoma of the pancreas.

Rebekah R. White; Herbert Hurwitz; Michael A. Morse; Catherine Lee; Mitchell S. Anscher; Erik K. Paulson; Marcia R. Gottfried; John Baillie; Malcolm S. Branch; Paul S. Jowell; Kevin McGrath; Bryan M. Clary; Theodore N. Pappas; Douglas S. Tyler

AbstractBackground: The use of neoadjuvant preoperative chemoradiotherapy CRT for pancreatic cancer has been advocated for its potential ability to optimize patient selection for surgical resection and to downstage locally advanced tumors. This article reports our experience with neoadjuvant CRT for localized pancreatic cancer. Methods: Since 1995, 111 patients with radiographically localized, pathologically confirmed pancreatic adenocarcinoma have received neoadjuvant external beam radiation therapy EBRT; median, 4500 cGy with 5-flourouracil–based chemotherapy. Tumors were defined as potentially resectable PR, n = 53 in the absence of arterial involvement and venous occlusion and locally advanced LA, n = 58 with arterial involvement or venous occlusion by CT. Results: Five patients 4.5% were not restaged due to death n = 3 or intolerance of therapy n = 2. Twenty-one patients 19% manifested distant metastatic disease on restaging CT. Twenty-eight patients with initially PR tumors 53% and 11 patients with initially LA tumors 19% were resected after CRT. Histologic examination revealed significant fibrosis in all resected specimens and two complete responses. Surgical margins were negative in 72%, and lymph nodes were negative in 70% of resected patients. Median survival in resected patients has not been reached at a median follow-up of 16 months. Conclusions: Neoadjuvant CRT provided an opportunity for patients with occult metastatic disease to avoid the morbidity of resection and resulted in tumor downstaging in a minority of patients with LA tumors. Survival after neoadjuvant CRT and resection appears to be at least comparable to survival after resection and adjuvant postoperative CRT.


Journal of Clinical Oncology | 2007

Intraoperative radiation therapy

Christopher G. Willett; Brian G. Czito; Douglas S. Tyler

The modern use of intraoperative radiation therapy (IORT) was initiated by the studies of Abe and colleagues at the University of Kyoto. This work stimulated significant laboratory and clinical investigation into the use of IORT throughout Japan, Europe, and the United States. Because of this experience, single high doses of irradiation can be safely delivered to a tumor volume in appropriate clinical situations. Most importantly, this high dose of additional radiation treatment yields improved local control of selected tumors. Treatment programs of external beam radiation therapy, surgical resection, and IORT for patients with locally advanced primary and recurrent rectal carcinoma and retroperitoneal sarcoma have yielded excellent local control and higher survival rates. The future of IORT will be in the successful integration of this therapy into multimodality treatment programs of chemotherapy, external beam irradiation, and surgery for locally advanced malignancies.


Journal of Clinical Oncology | 2006

Randomized Multicenter Trial of Hyperthermic Isolated Limb Perfusion With Melphalan Alone Compared With Melphalan Plus Tumor Necrosis Factor: American College of Surgeons Oncology Group Trial Z0020

Wendy R. Cornett; Linda M. McCall; Rebecca P. Petersen; Merrick I. Ross; Henry A. Briele; R. Dirk Noyes; Jeffrey J. Sussman; William G. Kraybill; John M. Kane; H. Richard Alexander; Jeffrey E. Lee; Paul F. Mansfield; James F. Pingpank; David J. Winchester; Richard L. White; Vijaya Chadaram; James E. Herndon; Douglas L. Fraker; Douglas S. Tyler

PURPOSE To determine in a randomized prospective multi-institutional trial whether the addition of tumor necrosis factor alpha (TNF-alpha) to a melphalan-based hyperthermic isolated limb perfusion (HILP) treatment would improve the complete response rate for locally advanced extremity melanoma. PATIENTS AND METHODS Patients with locally advanced extremity melanoma were randomly assigned to receive melphalan or melphalan plus TNF-alpha during standard HILP. Patient randomization was stratified according to disease/treatment status and regional nodal disease status. RESULTS The intervention was completed in 124 patients of the 133 enrolled. Grade 4 adverse events were observed in 14 (12%) of 129 patients, with three (4%) of 64 in the melphalan-alone arm and 11 (16%) of 65 in the melphalan-plus-TNF-alpha arm (P = .0436). There were two toxicity-related lower extremity amputations in the melphalan-plus-TNF-alpha arm, and one disease progression-related upper extremity amputation in the melphalan-alone arm. There was no treatment-related mortality in either arm of the study. One hundred sixteen patients were assessable at 3 months postoperatively. Sixty-four percent of patients (36 of 58) in the melphalan-alone arm and 69% of patients (40 of 58) in the melphalan-plus-TNF-alpha arm showed a response to treatment at 3 months, with a complete response rate of 25% (14 of 58 patients) in the melphalan-alone arm and 26% (15 of 58 patients) in the melphalan-plus-TNF-alpha arm (P = .435 and P = .890, respectively). CONCLUSION In locally advanced extremity melanoma treated with HILP, the addition of TNF-alpha to melphalan did not demonstrate a significant enhancement of short-term response rates over melphalan alone by the 3-month follow-up, and TNF-alpha plus melphalan was associated with a higher complication rate.


Annals of Surgery | 2001

Neoadjuvant chemoradiation for rectal cancer: analysis of clinical outcomes from a 13-year institutional experience.

Mark W. Onaitis; Robert B. Noone; Matthew G. Hartwig; Herbert Hurwitz; Michael A. Morse; Paul S. Jowell; Kevin McGrath; Catherine Lee; Mitchell S. Anscher; Bryan M. Clary; Christopher R. Mantyh; Theodore N. Pappas; Kirk A. Ludwig; Hilliard F. Seigler; Douglas S. Tyler

ObjectiveTo examine clinical outcomes in patients receiving neoadjuvant chemoradiation for locally advanced rectal adenocarcinoma. Summary Background DataPreoperative radiation therapy, either alone or in combination with 5-fluorouracil-based chemotherapy, has proven both safe and effective in the treatment of rectal cancer. However, data are lacking regarding which subgroups of patients benefit from the therapy in terms of decreased local recurrence and increased survival rates. MethodsA retrospective chart review was performed on 141 consecutive patients who received neoadjuvant chemoradiation (5-fluorouracil ± cisplatin and 4,500–5,040 cGy) for biopsy-proven locally advanced adenocarcinoma of the rectum. Surgery was performed 4 to 8 weeks after completion of chemoradiation. Standard statistical methods were used to analyze recurrence and survival. ResultsMedian follow-up was 27 months, and mean age was 59 years (range 28–81). Mean tumor distance from the anal verge was 6 cm (range 1–15). Of those staged before surgery with endorectal ultrasound or magnetic resonance imaging, 57% of stage II patients and 82% of stage III patients were downstaged. The chemotherapeutic regimens were well tolerated, and resections were performed on 140 patients. The percentage of sphincter-sparing procedures increased from 20% before 1996 to 76% after 1996. On pathologic analysis, 24% of specimens were T0. However, postoperative pathologic T stage had no effect on either recurrence or survival. Positive lymph node status predicted increased local recurrence and decreased survival. ConclusionsNeoadjuvant chemoradiation is safe, effective, and well tolerated. Postoperative lymph node status is the only independent predictor of recurrence and survival.


Journal of Clinical Oncology | 2006

Increased Toxicity With Gefitinib, Capecitabine, and Radiation Therapy in Pancreatic and Rectal Cancer: Phase I Trial Results

Brian G. Czito; Christopher G. Willett; Johanna C. Bendell; Michael A. Morse; Douglas S. Tyler; Nishan H. Fernando; Christopher R. Mantyh; Gerard C. Blobe; Wanda Honeycutt; Daohai Yu; Bryan M. Clary; Theodore N. Pappas; Kirk A. Ludwig; Herbert Hurwitz

PURPOSE Overexpression of epidermal growth factor receptor (EGFR) has been associated with aggressive tumor phenotypes, chemotherapy, and radiation resistance, as well as poor survival in preclinical and clinical models. The EGFR inhibitor gefitinib potentiates chemotherapy and radiation tumor cytotoxicity in preclinical models, including pancreatic and colorectal cancer. We initiated two phase I trials assessing the combination of gefitinib, capecitabine, and radiation in patients with localized pancreatic and rectal cancer. PATIENTS AND METHODS Patients with pathologically confirmed adenocarcinoma of the pancreas and rectum were eligible. Pretreatment staging included computed tomography, endoscopic ultrasound, and surgical evaluation. Patients received 50.4 Gy of external-beam radiation therapy to the tumor in 28 fractions. Capecitabine and gefitinib were administered throughout the radiation course. Following completion, patients were restaged and considered for resection. Primary end points included determination of dose-limiting toxicity (DLT) and a phase II dose; secondary end points included determination of non-DLTs and preliminary radiographic and pathologic response rates. RESULTS Ten patients were entered in the pancreatic study and six in the rectal study. DLT was seen in six of 10 patients in the pancreatic study and two of six patients in the rectal study. The primary DLT in both studies was diarrhea. Two patients developed arterial thrombi. CONCLUSION The combination of gefitinib, capecitabine, and radiation in pancreatic and rectal cancer patients resulted in significant toxicity. A recommended phase II dose was not determined in either of our studies. Further investigation with this combination should be approached with caution.


Annals of Surgical Oncology | 2006

Melanoma Patients with Positive Sentinel Nodes Who Did Not Undergo Completion Lymphadenectomy: A Multi-Institutional Study

Sandra L. Wong; Donald L. Morton; John F. Thompson; Jeffrey E. Gershenwald; Stanley P. L. Leong; Douglas S. Reintgen; Haim Gutman; Michael S. Sabel; Grant W. Carlson; Kelly M. McMasters; Douglas S. Tyler; James S. Goydos; Alexander M.M. Eggermont; Omgo E. Nieweg; A. Benedict Cosimi; Adam I. Riker; Daniel G. Coit

BackgroundCompletion lymph node dissection (CLND) is considered the standard of care in melanoma patients found to have sentinel lymph node (SLN) metastasis. However, the therapeutic utility of CLND is not known. The natural history of patients with positive SLNs who do not undergo CLND is undefined. This multi-institutional study was undertaken to characterize patterns of failure and survival rates in these patients and to compare results with those of positive-SLN patients who underwent CLND.MethodsSurgeons from 16 centers contributed data on 134 positive-SLN patients who did not undergo CLND. SLN biopsy was performed by using each institution’s established protocols. Patients were followed up for recurrence and survival.ResultsIn this study population, the median age was 59 years, and 62% were male. The median tumor thickness was 2.6 mm, 77% of tumors had invasion to Clark level IV/V, and 33% of lesions were ulcerated. The primary melanoma was located on the extremities, trunk, and head/neck in 45%, 43%, and 12%, respectively. The median follow-up was 20 months. The median time to recurrence was 11 months. Nodal recurrence was a component of the first site of recurrence in 20 patients (15%). Nodal recurrence–free survival was statistically insignificantly worse than that seen in a contemporary cohort of patients who underwent CLND. Disease-specific survival for positive-SLN patients who did not undergo CLND was 80% at 36 months, which was not significantly different from that of patients who underwent CLND.ConclusionsThis study underscores the importance of ongoing prospective randomized trials in determining the therapeutic value of CLND after positive SLN biopsy in melanoma patients.


Surgery | 2003

Iodine -131 metaiodobenzylguanidine is an effective treatment for malignant pheochromocytoma and paraganglioma☆

Shawn D. Safford; R. Edward Coleman; Jon P. Gockerman; Joseph O. Moore; Jerome M. Feldman; George S. Leight; Douglas S. Tyler; John A. Olson

INTRODUCTION Iodine 131-meta-iodobenzylguanidine ((131)I-MIBG) has been applied to the palliative treatment of metastatic pheochromocytoma in small studies. We report our institutional experience for the treatment of metastatic pheochromocytoma and paraganglioma. METHODS We performed a retrospective review of 33 patients with metastatic pheochromocytoma (n=22) and paraganglioma (n=11) treated at our institution with (131)I-MIBG over a 10-year period. RESULTS Patients received a mean dose of 388+/-131 mCi (131)I-MIBG. Median survival after treatment was 4.7 years. Most patients experienced a symptomatic response leading to an improved survival (4.7 years vs 1.8 years, P<.01). Patients with a measurable hormone response demonstrated an increased survival in comparison to those with no response (4.7 years vs 2.6 years, P=.01). Patients who received a high dose (>500 mCi) as their initial therapy also had improved survival (3.8 years vs 2.8 years, P=.02). CONCLUSION These data support (131)I-MIBG treatment for select patients with metastatic pheochromocytoma. In our experience, prolonged survival was best predicted by symptomatic and hormone response to (131)I-MIBG treatment. An initial dose of 500 mCi may be optimal. The benefit of (131)I-MIBG treatment for metastatic pheochromocytoma must also be weighed against its side effects.


Annals of Surgical Oncology | 2001

Complete response to neoadjuvant chemoradiation for rectal cancer does not influence survival

Mark W. Onaitis; Robert B. Noone; Ryan C. Fields; Herbert Hurwitz; Michael A. Morse; Paul S. Jowell; Kevin McGrath; Catherine Lee; Mitchell S. Anscher; Bryan M. Clary; Christopher R. Mantyh; Theodore N. Pappas; Kirk A. Ludwig; Hilliard F. Seigler; Douglas S. Tyler

Background: Up to 30% of patients with locally advanced rectal cancer have a complete clinical or pathologic response to neoadjuvant chemoradiation. This study analyzes complete clinical and pathologic responders among a large group of rectal cancer patients treated with neoadjuvant chemoradiation.Methods: From 1987 to 2000, 141 consecutive patients with biopsy-proven, locally advanced rectal cancer were treated with preoperative 5-fluorouracil-based chemotherapy and radiation. Clinical restaging after treatment consisted of proctoscopic examination and often computed tomography scan. One hundred forty patients then underwent operative resection, with results tracked in a database. Standard statistical methods were used to examine the outcomes of those patients with complete clinical or pathologic responses.Results: No demographic differences were detected between either clinical complete and clinical partial responders or pathologic complete and pathologic partial responders. The positive predictive value of clinical restaging was 60%, and accuracy was 82%. By use of the Kaplan-Meier life table analysis, clinical complete responders had no advantage in local recurrence, disease-free survival, or overall survival rates when compared with clinical partial responders. Pathologic complete responders also had no recurrence or survival advantage when compared with pathologic partial responders. Of the 34 pathologic T0 tumors, 4 (13%) had lymph node metastases.Conclusions: Clinical assessment of complete response to neoadjuvant chemoradiation is unreliable. Micrometastatic disease persists in a proportion of patients despite pathologic complete response. Observation or local excision for patients thought to be complete responders should be undertaken with caution.

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