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Dive into the research topics where Leonard L. Gunderson is active.

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Featured researches published by Leonard L. Gunderson.


The New England Journal of Medicine | 1991

Effective Surgical Adjuvant Therapy for High-Risk Rectal Carcinoma

James E. Krook; Charles G. Moertel; Leonard L. Gunderson; Harry S. Wieand; Roger T. Collins; Robert W. Beart; Theodore P. Kubista; Michael A. Poon; William C. Meyers; James A. Mailliard; Donald I. Twito; Roscoe F. Morton; Michael H. Veeder; Thomas E. Witzig; Stephen S. Cha; Subhash C. Vidyarthi

BACKGROUND Radiation therapy as an adjunct to surgery for rectal cancer has been shown to reduce local recurrence but has not improved survival. In a previous study, combined radiation and chemotherapy improved survival significantly as compared with surgery alone, but not as compared with adjuvant radiation, which many regard as standard therapy. We designed a combination regimen to optimize the contribution of chemotherapy, decrease recurrence, and improve survival as compared with adjuvant radiation alone. METHODS Two hundred four patients with rectal carcinoma that was either deeply invasive or metastatic to regional lymph nodes were randomly assigned to postoperative radiation alone (4500 to 5040 cGy) or to radiation plus fluorouracil, which was both preceded and followed by a cycle of systemic therapy with fluorouracil plus semustine (methyl-CCNU). RESULTS After a median follow-up of more than seven years, the combined therapy had reduced the recurrence of rectal cancer by 34 percent (P = 0.0016; 95 percent confidence interval, 12 to 50 percent). Initial local recurrence was reduced by 46 percent (P = 0.036; 95 percent confidence interval, 2 to 70 percent), and distant metastasis by 37 percent (P = 0.011; 95 percent confidence interval, 9 to 57 percent). In addition, combined therapy reduced the rate of cancer-related deaths by 36 percent (P = 0.0071; 95 percent confidence interval, 14 to 53 percent) and the overall death rate by 29 percent (P = 0.025; 95 percent confidence interval, 7 to 45 percent). Its acute toxic effects included nausea, vomiting, diarrhea, leukopenia, and thrombocytopenia. These effects were seldom severe. Severe, delayed treatment-related reactions, usually small-bowel obstruction requiring surgery, occurred in 6.7 percent of all patients receiving radiation, and the frequencies of these complications were comparable in both treatment groups. CONCLUSIONS The combination of postoperative local therapy with radiation plus fluorouracil and systemic therapy with a fluorouracil-based regimen significantly and substantively improves the results of therapy for rectal carcinoma with a poor prognosis, as compared with postoperative radiation alone.


The New England Journal of Medicine | 1998

Chemotherapy followed by surgery compared with surgery alone for localized esophageal cancer.

David P. Kelsen; Robert J. Ginsberg; Thomas F. Pajak; Daniel G. Sheahan; Leonard L. Gunderson; Joanne E. Mortimer; Norman C. Estes; Daniel G. Haller; Jaffer A. Ajani; Walter Kocha; Bruce D. Minsky; Jack A. Roth

BACKGROUND We performed a multi-institutional randomized trial comparing preoperative chemotherapy followed by surgery with surgery alone for patients with local and operable esophageal cancer. METHODS Preoperative chemotherapy for patients randomly assigned to the chemotherapy group included three cycles of cisplatin and fluorouracil. Surgery was performed two to four weeks after the completion of the third cycle; patients also received two additional cycles of chemotherapy after the operation. Patients randomly assigned to the immediate-surgery group underwent the same surgical procedure. The main end point was overall survival. RESULTS Of the 440 eligible patients with adequate data , 213 were assigned to receive preoperative chemotherapy and 227 to undergo immediate surgery. After a median possible study time of 55.4 months, there were no significant differences between the two groups in median survival: 14.9 months for the patients who received preoperative chemotherapy and 16.1 months for those who underwent immediate surgery (P=0.53). At one year, the survival rate was 59 percent for those who received chemotherapy and 60 percent for those who had surgery alone; at two years, survival was 35 percent and 37 percent, respectively. The toxic effects of chemotherapy were tolerable, and the addition of chemotherapy did not appear to increase the morbidity or mortality associated with surgery. There were no differences in survival between patients with squamous-cell carcinoma and those with adenocarcinoma. Weight loss was a significant predictor of poor outcome (P=0.03). With the addition of chemotherapy, there was no change in the rate of recurrence at locoregional or distant sites. CONCLUSIONS Preoperative chemotherapy with a combination of cisplatin and fluorouracil did not improve overall survival among patients with epidermoid cancer or adenocarcinoma of the esophagus.


The New England Journal of Medicine | 1994

Improving Adjuvant Therapy for Rectal Cancer by Combining Protracted-Infusion Fluorouracil with Radiation Therapy after Curative Surgery

Michael J. O'Connell; James A. Martenson; Harry S. Wieand; James E. Krook; John S. Macdonald; Daniel G. Haller; Robert J. Mayer; Leonard L. Gunderson; Tyvin A. Rich

BACKGROUND The combination of radiation therapy and chemotherapy with fluorouracil plus semustine after surgery has been established as an effective approach to decreasing the risk of tumor relapse and improving survival in patients with rectal cancer who are at high risk for relapse or death. We sought to determine whether the efficacy of chemotherapy could be improved by administering fluorouracil by protracted infusion throughout the duration of radiation therapy and whether the omission of semustine would reduce the toxicity and delayed complications of chemotherapy without decreasing its antitumor efficacy. METHODS Six hundred sixty patients with TNM stage II or III rectal cancer received intermittent bolus injections or protracted venous infusions of fluorouracil during postoperative radiation to the pelvis. They also received systemic chemotherapy with semustine plus fluorouracil or with fluorouracil alone in a higher dose, administered before and after the pelvic irradiation. RESULTS With a median follow-up of 46 months among surviving patients, patients who received a protracted infusion of fluorouracil had a significantly increased time to relapse (P = 0.01) and improved survival (P = 0.005). There was no evidence of a beneficial effect in the patients who received semustine plus fluorouracil. CONCLUSIONS A protracted infusion of fluorouracil during pelvic irradiation improved the effect of combined-treatment postoperative adjuvant therapy in patients with high-risk rectal cancer. Semustine plus fluorouracil was not more effective than a higher dose of systemic fluorouracil given alone.


International Journal of Radiation Oncology Biology Physics | 2000

Common toxicity criteria: version 2.0. an improved reference for grading the acute effects of cancer treatment: impact on radiotherapy

Andy Trotti; Roger W. Byhardt; Joanne Stetz; Clement K. Gwede; Benjamin W. Corn; Karen Fu; Leonard L. Gunderson; Beryl McCormick; Mitchell Morris; Tyvin A. Rich; William U. Shipley; W.J. Curran

In 1997, the National Cancer Institute (NCI) led an effort to revise and expand the Common Toxicity Criteria (CTC) with the goal of integrating systemic agent, radiation, and surgical criteria into a comprehensive and standardized system. Representatives from the Radiation Therapy Oncology Group (RTOG) participated in this process in an effort to improve acute radiation related criteria and to achieve better clarity and consistency among modalities. CTC v. 2.0 replaces the previous NCI CTC and the RTOG Acute Radiation Morbidity Scoring Criteria and includes more than 260 individual adverse events with more than 100 of these applicable to acute radiation effects. One of the advantages of the revised criteria for radiation oncology is the opportunity to grade acute radiation effects not adequately captured under the previous RTOG system. A pilot study conducted by the RTOG indicated the new criteria are indeed more comprehensive and were preferred by research associates. CTC v. 2.0 represents an improvement in the evaluation and grading of acute toxicity for all modalities.


Cancer | 1974

Areas of failure found at reoperation (second or symptomatic look) following “curative surgery” for adenocarcinoma of the rectum: Clinicopathologic correlation and implications for adjuvant therapy

Leonard L. Gunderson; Henry Sosin

Seventy‐five patients with complete bowel wall penetration and/or positive lymph nodes at the time of initial “curative surgery” had planned single or multiple reoperations at the University of Minnesota. Tumor due to rectal carcinoma was found in 52. Four were converted to disease‐free status. Areas of failure were analyzed in detail. Distant metastasis (DM) alone was uncommon. Peritoneal seeding (PS) was rare. Local failure and/or regional lymph node metastases (LF‐RF) occurred as the only failure in nearly 50% of the failure group and as some component in 92%. Patterns of failure are fairly predictable if anatomical factors and initial pathologic extent of tumor are considered. Postoperative irradiation may be a logical adjuvant in view of the high percentage of local‐regional failures and the ability to identify subgroups of patients at highest risk for such failure.


JAMA | 2008

Fluorouracil, Mitomycin, and Radiotherapy vs Fluorouracil, Cisplatin, and Radiotherapy for Carcinoma of the Anal Canal: A Randomized Controlled Trial

Jaffer A. Ajani; Kathryn Winter; Leonard L. Gunderson; J. Pedersen; Al B. Benson; Charles R. Thomas; Robert J. Mayer; Michael G. Haddock; Tyvin A. Rich; Christopher G. Willett

CONTEXT Chemoradiation as definitive therapy is the preferred primary therapy for patients with anal canal carcinoma; however, the 5-year disease-free survival rate from concurrent fluorouracil/mitomycin and radiation is only approximately 65%. OBJECTIVE To compare the efficacy of cisplatin-based (experimental) therapy vs mitomycin-based (standard) therapy in treatment of anal canal carcinoma. DESIGN, SETTING, AND PARTICIPANTS US Gastrointestinal Intergroup trial RTOG 98-11, a multicenter, phase 3, randomized controlled trial comparing treatment with fluorouracil plus mitomycin and radiotherapy vs treatment with fluorouracil plus cisplatin and radiotherapy in 682 patients with anal canal carcinoma enrolled between October 31, 1998, and June 27, 2005. Stratifications included sex, clinical nodal status, and tumor diameter. INTERVENTION Participants were randomly assigned to 1 of 2 intervention groups: (1) the mitomycin-based group (n = 341), who received fluorouracil (1000 mg/m2 on days 1-4 and 29-32) plus mitomycin (10 mg/m2 on days 1 and 29) and radiotherapy (45-59 Gy) or (2) the cisplatin-based group (n = 341), who received fluorouracil (1000 mg/m2 on days 1-4, 29-32, 57-60, and 85-88) plus cisplatin (75 mg/m2 on days 1, 29, 57, and 85) and radiotherapy (45-59 Gy; start day = day 57). MAIN OUTCOME MEASURES The primary end point was 5-year disease-free survival; secondary end points were overall survival and time to relapse. RESULTS A total of 644 patients were assessable. The median follow-up for all patients was 2.51 years. Median age was 55 years, 69% were women, 27% had a tumor diameter greater than 5 cm, and 26% had clinically positive nodes. The 5-year disease-free survival rate was 60% (95% confidence interval [CI], 53%-67%) in the mitomycin-based group and 54% (95% CI, 46%-60%) in the cisplatin-based group (P = .17). The 5-year overall survival rate was 75% (95% CI, 67%-81%) in the mitomycin-based group and 70% (95% CI, 63%-76%) in the cisplatin-based group (P = .10). The 5-year local-regional recurrence and distant metastasis rates were 25% (95% CI, 20%-30%) and 15% (95% CI, 10%-20%), respectively, for mitomycin-based treatment and 33% (95% CI, 27%-40%) and 19% (95% CI, 14%-24%), respectively, for cisplatin-based treatment. The cumulative rate of colostomy was significantly better for mitomycin-based than cisplatin-based treatment (10% vs 19%; P = .02). Severe hematologic toxicity was worse with mitomycin-based treatment (P < .001). CONCLUSIONS In this population of patients with anal canal carcinoma, cisplatin-based therapy failed to improve disease-free-survival compared with mitomycin-based therapy, but cisplatin-based therapy resulted in a significantly worse colostomy rate. These findings do not support the use of cisplatin in place of mitomycin in combination with fluorouracil and radiotherapy in the treatment of anal canal carcinoma. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT00003596.


Journal of Clinical Oncology | 2001

Impact of Number of Nodes Retrieved on Outcome in Patients With Rectal Cancer

Joel E. Tepper; Michael J. O'Connell; Donna Niedzwiecki; Donna Hollis; Carolyn Compton; Al B. Benson; B. Cummings; Leonard L. Gunderson; John S. Macdonald; Robert J. Mayer

PURPOSE We postulated that the pathologic evaluation of the lymph nodes of surgical specimens from patients with rectal cancer can have a substantial impact on time to relapse and survival. PATIENTS AND METHODS We analyzed data from 1,664 patients with T3, T4, or node-positive rectal cancer treated in a national intergroup trial of adjuvant therapy with chemotherapy and radiation therapy. Associations between the number of lymph nodes found by the pathologist in the surgical specimen and the time to relapse and survival outcomes were investigated. RESULTS Patients were divided into groups by nodal status and the corresponding quartiles of numbers of nodes examined. The number of nodes examined was significantly associated with time to relapse and survival among patients who were node-negative. For the first through fourth quartiles, the 5-year relapse rates were 0.37, 0.34, 0.26, and 0.19 (P: = .003), and the 5-year survival rates were 0.68, 0.73, 0.72, and 0.82 (P: = .02). No significant differences were found by quartiles among patients determined to be node-positive. We propose that observed differences are primarily related to the incorrect determination of nodal status in node-negative patients. Approximately 14 nodes need to be studied to define nodal status accurately. CONCLUSION These results suggest that the pathologic assessment of lymph nodes in surgical specimens is often inaccurate and that examining greater number of nodes increases the likelihood of proper staging. Some patients who might benefit from adjuvant therapy are misclassified as node-negative due to incomplete sampling of lymph nodes.


Journal of Clinical Oncology | 2012

Updated Analysis of SWOG-Directed Intergroup Study 0116: A Phase III Trial of Adjuvant Radiochemotherapy Versus Observation After Curative Gastric Cancer Resection

Stephen R. Smalley; Jacqueline Benedetti; Daniel G. Haller; Scott A. Hundahl; Norman Estes; Jaffer A. Ajani; Leonard L. Gunderson; Bryan H. Goldman; James A. Martenson; J. Milburn Jessup; Grant N. Stemmermann; Charles D. Blanke; John S. Macdonald

PURPOSE Surgical resection of gastric cancer has produced suboptimal survival despite multiple randomized trials that used postoperative chemotherapy or more aggressive surgical procedures. We performed a randomized phase III trial of postoperative radiochemotherapy in those at moderate risk of locoregional failure (LRF) following surgery. We originally reported results with 4-year median follow-up. This update, with a more than 10-year median follow-up, presents data on failure patterns and second malignancies and explores selected subset analyses. PATIENTS AND METHODS In all, 559 patients with primaries ≥ T3 and/or node-positive gastric cancer were randomly assigned to observation versus radiochemotherapy after R0 resection. Fluorouracil and leucovorin were administered before, during, and after radiotherapy. Radiotherapy was given to all LRF sites to a dose of 45 Gy. RESULTS Overall survival (OS) and relapse-free survival (RFS) data demonstrate continued strong benefit from postoperative radiochemotherapy. The hazard ratio (HR) for OS is 1.32 (95% CI, 1.10 to 1.60; P = .0046). The HR for RFS is 1.51 (95% CI, 1.25 to 1.83; P < .001). Adjuvant radiochemotherapy produced substantial reduction in both overall relapse and locoregional relapse. Second malignancies were observed in 21 patients with radiotherapy versus eight with observation (P = .21). Subset analyses show robust treatment benefit in most subsets, with the exception of patients with diffuse histology who exhibited minimal nonsignificant treatment effect. CONCLUSION Intergroup 0116 (INT-0116) demonstrates strong persistent benefit from adjuvant radiochemotherapy. Toxicities, including second malignancies, appear acceptable, given the magnitude of RFS and OS improvement. LRF reduction may account for the majority of overall relapse reduction. Adjuvant radiochemotherapy remains a rational standard therapy for curatively resected gastric cancer with primaries T3 or greater and/or positive nodes.


Cancer | 1984

Carcinoma of the anal canal. A clinical and pathologic study of 188 cases.

Bruce M. Boman; Charles G. Moertel; Michael J. O'Connell; Mark Scott; Louis H. Weiland; Robert W. Beart; Leonard L. Gunderson; Robert J. Spencer

Among 188 patients presenting with carcinoma of the anal canal the predominant cell types were squamous cell (56%) and nonkeratinizing basaloid (35%). Thirteen patients who had predominantly small (≤2 cm) and only superficially invasive squamous cell lesions were treated with local excision, and although one required later abdominal perineal (AP) resection for local recurrence, all were apparently cured. Local excision should be preferred as initial treatment for such lesions. One hundred eighteen patients with squamous cell and nonkeratinizing basaloid carcinomas were primarily treated with AP resection. The operative mortality rate was 2.5%. Among 114 patients who survived surgery and had adequate follow‐up, 40% developed recurrent disease, and 71% have survived 5 or more years. Pathologic staging based on depth of tumor invasion and regional nodal involvement was strongly predictive of survival as was tumor histology with progressively poorer survival rates from low‐grade squamous cell to high‐grade squamous cell to nonkeratinizing basaloid types. Tumor size was inversely related to prognosis and was strongly associated with stage. Squamous cell anal carcinoma was dominantly a local disease with approximately 70% of patients presenting with tumor apparently limited to the bowel wall, only 20% with regional node involvement and only 2% with distant metastasis. Even among those patients who recurred after AP resection approximately 80% had all known disease still limited to the pelvic area. Corresponding figures for nonkeratinizing basaloid tumors were 50 percent presenting limited to the bowel wall, 30% with regional nodes, 20% with distant metastasis, and 60% with initial recurrence limited to the pelvis. Among the 13 patients studied with small cell anal carcinoma, the authors found the disease to be very virulent either initially presenting with or rapidly evolving into diffuse dissemination. Only one of the seven patients who could be treated surgically survived 5 years. As is true for small cell carcinomas primary to other sites, this neoplasm should be regarded as a systemic disease. With these findings as a foundation, possible future strategies for management of anal carcinoma are discussed.


Journal of Clinical Oncology | 2016

Impact of T and N stage and treatment on survival and relapse in adjuvant rectal cancer: a pooled analysis.

Leonard L. Gunderson; Daniel J. Sargent; Joel E. Tepper; Norman Wolmark; Michael J. O'Connell; Mirsada Begovic; Cristine Allmer; Linda H. Colangelo; Steven R. Smalley; Daniel G. Haller; James A. Martenson; Robert J. Mayer; Tyvin A. Rich; Jaffer A. Ajani; John S. Macdonald; Christopher G. Willett; Richard M. Goldberg

PURPOSE To determine survival and relapse rates by T and N stage and treatment method in five randomized phase III North American rectal adjuvant studies. PATIENTS AND METHODS Data were pooled from 3,791 eligible patients enrolled onto North Central Cancer Treatment Group (NCCTG) 79-47-51, NCCTG 86-47-51, US Gastrointestinal Intergroup 0114, National Surgical Adjuvant Breast and Bowel Project (NSABP) R01, and NSABP R02. Surgery alone (S) was the treatment arm in 179 patients. The remaining patients received adjuvant treatment as follows: irradiation (RT) alone (n = 281), RT + fluorouracil (FU) +/- semustine bolus chemotherapy (CT; n = 779), RT + protracted venous infusion CT (n = 325), RT + FU +/- leucovorin or levamisole bolus CT (n = 1,695), or CT alone (n = 532). Five-year follow-up was available in 94% of surviving patients, and 8-year follow-up, in 62%. RESULTS Overall (OS) and disease-free survival were dependent on TN stage, NT stage, and treatment method. Even among N2 patients, T substage influenced 5-year OS (T1-2, 67%; T3, 44%; T4, 37%; P <.001). Three risk groups of patients were defined: (1) intermediate (T1-2/N1, T3/N0), (2) moderately high (T1-2/N2, T3/N1, T4/N0), and (3) high (T3/N2, T4/N1, T4/N2). For intermediate-risk patients, those receiving S plus CT had 5-year OS rates of 85% (T1-2/N1) and 84% (T3/N0), which was similar to results with S plus RT plus CT (T1-2/N1, 78% to 83%; T3/N0, 74% to 80%). For moderately high-risk lesions, 5-year OS ranged from 43% to 70% with S plus CT, and 44% to 80% with S plus RT plus CT. For high-risk lesions, 5-year OS ranged from 25% to 45% with S plus CT, and 29% to 57% with S plus RT plus CT. CONCLUSION Different treatment strategies may be indicated for intermediate-risk versus moderately high- or high-risk patients based on differential survival rates and rates of relapse. Use of trimodality treatment for all patients with intermediate-risk lesions may be excessive, since S plus CT resulted in 5-year OS of approximately 85%; however, 5-year disease-free survival rates with S plus CT were 78% (T1-2/N1) and 69%(T3/N0), indicating room for improvement.

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Joel E. Tepper

University of North Carolina at Chapel Hill

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Jaffer A. Ajani

University of Texas MD Anderson Cancer Center

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