Precision Medicine and Pancreatic Cancer: A Gemcitabine Pathway Approach.

OBJECTIVES: There is a need for validated predictive markers of gemcitabine response to guide precision medicine treatment in pancreatic cancer. We previously validated human equilibrative nucleoside transporter 1 as a predictive marker of gemcitabine treatment response using Radiation Therapy Oncology Group 9704. Controversy exists about the predictive value of gemcitabine metabolism pathway biomarkers: deoxycytidine kinase (DCK), ribonucleotide reductase 1 (RRM1), RRM2, and p53R2. METHODS: Radiation Therapy Oncology Group 9704 prospectively randomized 538 patients after pancreatic resection to receive either 5-fluorouracil or gemcitabine. Tumor DCK, RRM1, RRM2, and p53R protein expressions were analyzed using a tissue microarray and immunohistochemistry and correlated with treatment outcome (overall survival and disease-free survival) by unconditional logistic regression analysis. RESULTS: There were 229 patients eligible for analysis from both the 5-fluorouracil and gemcitabine arms. Only RRM2 protein expression, and not DCK, RRM1, or p53R2 protein expression, was associated with survival in the gemcitabine treatment arm. CONCLUSIONS: Despite limited data from other nonrandomized treatment data, our data do not support the predictive value of DCK, RRM1, or p53R2. Efforts should focus on human equilibrative nucleoside transporter 1 and possibly RRM2 as valid predictive markers of the treatment response of gemcitabine in pancreatic cancer.

Updated analysis of SWOG-directed intergroup study 0116: a phase III trial of adjuvant radiochemotherapy versus observation after curative gastric cancer resection.

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.

Failure to adhere to protocol specified radiation therapy guidelines was associated with decreased survival in RTOG 9704--a phase III trial of adjuvant chemotherapy and chemoradiotherapy for patients with resected adenocarcinoma of the pancreas.

PURPOSE: In Radiation Therapy Oncology Group 9704, as previously published, patients with resected pancreatic adenocarcinoma received continuous infusion 5-FU and concurrent radiotherapy (5FU-RT). 5FU-RT treatment was preceded and followed by randomly assigned chemotherapy, either 5-FU or gemcitabine. This analysis explored whether failure to adhere to specified RT guidelines influenced survival and/or toxicity. METHODS AND MATERIALS: RT requirements were protocol specified. Adherence was scored as per protocol (PP) or less than per protocol (

Fluorouracil-based chemoradiation with either gemcitabine or fluorouracil chemotherapy after resection of pancreatic adenocarcinoma: 5-year analysis of the U.S. Intergroup/RTOG 9704 phase III trial.

BACKGROUND: The impact of the addition of gemcitabine to 5-fluorouracil (5-FU) chemoradiation (CRT) on 5-year overall survival (OS) in resected pancreatic adenocarcinoma are presented with updated results of a phase III trial. METHODS: After resection of pancreatic adenocarcinoma, patients were randomized to pre- and post-CRT 5-FU versus pre- and post-CRT gemcitabine. 5-FU was provided continuously at 250 mg/m(2)/day, and gemcitabine was provided at 1000 mg/m(2) weekly. Both were provided over 3 weeks before and 12 weeks after CRT. CRT was provided at 50.4 Gy with continuously provided 5-FU. The primary end point was survival for all patients and for patients with tumor of the pancreatic head. RESULTS: Four hundred fifty-one patients were eligible. Univariate analysis showed no difference in OS. Pancreatic head tumor patients (n = 388) had a median survival and 5-year OS of 20.5 months and 22% with gemcitabine versus 17.1 months and 18% with 5-FU. On multivariate analysis, patients on the gemcitabine arm with pancreatic head tumors experienced a trend toward improved OS (P = 0.08). First site of relapse local recurrence in 28% of patients versus distant relapse in 73%. CONCLUSIONS: The sequencing of 5-FU CRT with gemcitabine as done in this trial is not associated with a statistically significant improvement in OS. Despite local recurrence being approximately half of that reported in previous adjuvant trials, distant disease relapse still occurs in ≥ 70% of patients. These findings serve as the basis for the recently activated EORTC/U.S. Intergroup RTOG 0848 phase III adjuvant trial evaluating the impact of CRT after completion of a full course of gemcitabine.

The influence of total nodes examined, number of positive nodes, and lymph node ratio on survival after surgical resection and adjuvant chemoradiation for pancreatic cancer: a secondary analysis of RTOG 9704.

PURPOSE: Lymph node status is an important predictor of survival in pancreatic cancer. We performed a secondary analysis of Radiation Therapy Oncology Group (RTOG) 9704, an adjuvant chemotherapy and chemoradiation trial, to determine the influence of lymph node factors--number of positive nodes (NPN), total nodes examined (TNE), and lymph node ratio (LNR ratio of NPN to TNE)--on OS and disease-free survival (DFS). PATIENT AND METHODS: Eligible patients from RTOG 9704 form the basis of this secondary analysis of lymph node parameters. Actuarial estimates for OS and DFS were calculated using Kaplan-Meier methods. Cox proportional hazards models were performed to evaluate associations of NPN, TNE, and LNR with OS and DFS. Multivariate Cox proportional hazards models were also performed. RESULTS: There were 538 patients enrolled in the RTOG 9704 trial. Of these, 445 patients were eligible with lymph nodes removed. Overall median NPN was 1 (min-max, 0-18). Increased NPN was associated with worse OS (HR=1.06, p=0.001) and DFS (HR=1.05, p=0.01). In multivariate analyses, both NPN and TNE were associated with OS and DFS. TNE>12, and >15 were associated with increased OS for all patients, but not for node-negative patients (n=142). Increased LNR was associated with worse OS (HR=1.01, p<0.0001) and DFS (HR=1.006, p=0.002). CONCLUSION: In patients who undergo surgical resection followed by adjuvant chemoradiation, TNE, NPN, and LNR are associated with OS and DFS. This secondary analysis of a prospective, cooperative group trial supports the influence of these lymph node parameters on outcomes after surgery and adjuvant therapy using contemporary techniques.

S9511: a Southwest Oncology Group phase II study of trimetrexate, 5-fluorouracil, and leucovorin in unresectable or metastatic adenocarcinoma of the stomach.

OBJECTIVE: The primary objective of this trial was to evaluate the response rate for trimetrexate in conjunction with 5-FU and leucovorin (LV) (= TFL) in the treatment of advanced gastric cancer in a phase II, cooperative group setting. METHODS: Patients with locally advanced, unresectable, or metastatic adenocarcinoma of the stomach received trimetrexate 110 mg/m IV over 60 minutes day 1, followed by 5-FU 500 mg/m IV bolus and LV 200 mg/m IV over 60 minutes day 2, followed by oral LV 15 mg every 6 hours x 7 doses, all weekly for 6 weeks followed by 2 weeks of rest, continued until progression. RESULTS: Characteristics for 37 eligible patients: median age 63 (range: 23-83); male/female: 69% of 31%; performance status 0/1/2 15/20/1. The confirmed response rate was 19%, and median overall survival was 6 months. Two patients died as a result of therapy, 1 because of infection without significant neutropenia, and 1 due to perforation of a responding gastric lesion. Seventy-two percent experienced grades 3 and 4 toxicity, most commonly diarrhea, fatigue, and lymphopenia. CONCLUSIONS: This regimen achieves response rates comparable to other 5-FU-based regimens, when used in treatment of incurable gastric cancer. Toxicity appears manageable.

Fluorouracil vs gemcitabine chemotherapy before and after fluorouracil-based chemoradiation following resection of pancreatic adenocarcinoma: a randomized controlled trial.

CONTEXT: Among patients with locally advanced metastatic pancreatic adenocarcinoma, gemcitabine has been shown to improve outcomes compared with fluorouracil. OBJECTIVE: To determine if the addition of gemcitabine to adjuvant fluorouracil chemoradiation (chemotherapy plus radiation) improves survival for patients with resected pancreatic adenocarcinoma. DESIGN, SETTING, AND PARTICIPANTS: Randomized controlled phase 3 trial of patients with complete gross total resection of pancreatic adenocarcinoma and no prior radiation or chemotherapy enrolled between July 1998 and July 2002 with follow-up through August 18, 2006, at 164 US and Canadian institutions. INTERVENTION: Chemotherapy with either fluorouracil (continuous infusion of 250 mg/m2 per day; n = 230) or gemcitabine (30-minute infusion of 1000 mg/m2 once per week; n = 221) for 3 weeks prior to chemoradiation therapy and for 12 weeks after chemoradiation therapy. Chemoradiation with a continuous infusion of fluorouracil (250 mg/m2 per day) was the same for all patients (50.4 Gy). MAIN OUTCOME MEASURES: Survival for all patients and survival for patients with pancreatic head tumors were the primary end points. Secondary end points included toxicity. RESULTS: A total of 451 patients were randomized, eligible, and analyzable. Patients with pancreatic head tumors (n = 388) had a median survival of 20.5 months and a 3-year survival of 31% in the gemcitabine group vs a median survival of 16.9 months and a 3-year survival of 22% in the fluorouracil group (hazard ratio, 0.82 [95% confidence interval, 0.65-1.03]; P = .09). The treatment effect was strengthened on multivariate analysis (hazard ratio, 0.80 [95% confidence interval, 0.63-1.00]; P = .05). Grade 4 hematologic toxicity was 1% in the fluorouracil group and 14% in the gemcitabine group (P < .001) without a difference in febrile neutropenia or infection. There were no differences in the ability to complete chemotherapy or radiation therapy (>85%). CONCLUSIONS: The addition of gemcitabine to adjuvant fluorouracil-based chemoradiation was associated with a survival benefit for patients with resected pancreatic cancer, although this improvement was not statistically significant. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00003216.

Synergy between cetuximab and chemotherapy in tumors of the gastrointestinal tract.

Cetuximab is a recently approved monoclonal antibody that targets the epidermal growth factor receptor, a receptor tyrosine kinase involved in the development and progression of colorectal cancer (CRC) and other solid tumors. Cetuximab, as a single agent or in combination with chemotherapy, has demonstrated significant clinical efficacy against CRC. Combinations of cetuximab with chemotherapy have proven to be well tolerated, with minimal overlap of toxicities between agents; and the anticancer synergy between cetuximab and traditional chemotherapy agents has made cetuximab a vital treatment for patients who are no longer responsive to chemotherapy alone. The U.S. Food and Drug Administration approved cetuximab in combination with irinotecan for the treatment of irinotecan-refractory metastatic CRC or as monotherapy for treating patients intolerant to irinotecan. Combination chemotherapies involving cetuximab as well as combinations involving cetuximab and other targeted agents, such as bevacizumab, an anti-vascular endothelial growth factor monoclonal antibody, constitute powerful new treatment options for the management of CRC. This review discusses recent clinical studies that have further defined this synergy, focusing primarily on tumors of the gastrointestinal tract.

Phase II trial of infusional fluorouracil, leucovorin, mitomycin, and dipyridamole in locally advanced unresectable pancreatic adenocarcinoma: SWOG S9700.

PURPOSE: To test the hypothesis that dual biochemical modulation of fluorouracil (FU) in combination with mitomycin improves the survival of patients with pancreas cancer. PATIENTS AND METHODS: Eligibility included stage II or III unresectable adenocarcinoma of the pancreas, performance status of 0 to 2, and adequate organ function. Treatment included FU 200 mg/m2/d via continuous intravenous infusion for 4 weeks followed by 1 week of rest; leucovorin 30 mg/m2 administered via intravenous bolus infusion on days 1, 8, 15, and 22, followed by 1 week rest; mitomycin 10 mg/m2 intravenous bolus infusion every 6 weeks for a total of four doses. Dipyridamole 75 mg was administered orally three times daily during the FU administration. RESULTS: Fifty patients (median age, 61 years; 23 males, 27 females) with localized unresectable pancreatic cancer were eligible for this trial. Twenty-seven patients survived past 1 year for a 1-year survival probability of 54% (95% CI, 40% to 68%). Overall, the objective response rate was 26% (confirmed and unconfirmed) in the 47 patients with measurable disease, with two complete responders. Six of the responding patients underwent curative successful resection of the tumor. The most common toxicity to treatment was stomatitis. Three patients had reversible hemolytic uremic syndrome. Five patients experienced grade 4 toxicity. There were no treatment-related deaths. CONCLUSION: Potential improvement in survival and resectability of localized unresectable pancreatic cancer may be attained without radiation. The strategy of dual biochemical modulation of FU warrants additional investigation in a randomized fashion.

Impact of hospital volume on recurrence and survival after surgery for gastric cancer.

BACKGROUND: Some, but not all, studies using registry data have suggested a small but significant long-term survival advantage following a curative surgical resection of gastric cancer at hospitals where the volume of such surgeries is high. However, because such data may be significantly influenced by the impact of postoperative mortality, and may be imbalanced for factors important to survival, the true nature of this relationship remains uncertain. METHODS: We conducted a nested volume-outcome study in a sample of 448 surgical survivors with stage IB through IV (M0) gastric and gastroesophageal junction adenocarcinoma, previously randomized to adjuvant chemoradiation after surgery or surgery alone, to measure the effect of hospital surgical volume, as assessed by Medicare claims data, on overall survival and gastric cancer recurrence. RESULTS: In this selected sample of postoperative survivors, hospital surgical volume was not predictive of overall survival (P = 0.46) or disease-free survival (P = 0.43) at a median follow-up of 8.9 years. However, patients who underwent either a D1 or D2 dissection at a high- or moderate-volume center experienced an adjusted hazard ratio of 0.80 (95% CI, 0.53-1.20) for overall survival and 0.78 (95% CI, 0.53-1.14) for disease-free survival compared with those patients resected at a low-volume hospital; these results were not statistically significant. When a D0 resection was performed, hospital procedure volume showed no impact on survival. CONCLUSIONS: Excluding the impact of perioperative mortality by utilizing prospectively recorded data from a large postoperative adjuvant trial, hospital procedure volume had no overall effect on long-term gastric cancer survival. The potential benefit of moderate- to high-volume centers for patients who underwent a D1 or D2 dissection requires confirmation in larger studies.

Gastric cancer: D2 dissection or low Maruyama Index-based surgery--a debate.

This article provides perspectives on the surgical approaches required optimally to manage patients with respectable gastric adenocarcinoma. The status of techniques of surgical resection in the management of gastric cancer is reviewed. The premise of this approach is that extended gastrectomy with D2 lymph node dissection is good. Also addressed are prognostic and predictive factors in the surgical treatment of stomach cancer.

ASCO 2006 update of recommendations for the use of tumor markers in gastrointestinal cancer.

PURPOSE: To update the recommendations for the use of tumor marker tests in the prevention, screening, treatment, and surveillance of gastrointestinal cancers. METHODS: For the 2006 update, an update committee composed of members from the full Panel was formed to complete the review and analysis of data published since 1999. Computerized literature searches of Medline and the Cochrane Collaboration Library were performed. The Update Committee's literature review focused attention on available systematic reviews and meta-analyses of published tumor marker studies. RECOMMENDATIONS AND CONCLUSION: For colorectal cancer, it is recommended that carcinoembryonic antigen (CEA) be ordered preoperatively, if it would assist in staging and surgical planning. Postoperative CEA levels should be performed every 3 months for stage II and III disease for at least 3 years if the patient is a potential candidate for surgery or chemotherapy of metastatic disease. CEA is the marker of choice for monitoring the response of metastatic disease to systemic therapy. Data are insufficient to recommend the routine use of p53, ras, thymidine synthase, dihydropyrimidine dehydrogenase, thymidine phosphorylase, microsatellite instability, 18q loss of heterozygosity, or deleted in colon cancer (DCC) protein in the management of patients with colorectal cancer. For pancreatic cancer, CA 19-9 can be measured every 1 to 3 months for patients with locally advanced or metastatic disease receiving active therapy. Elevations in serial CA 19-9 determinations suggest progressive disease but confirmation with other studies should be sought. New markers and new evidence to support the use of the currently reviewed markers will be evaluated in future updates of these guidelines.

Phase III trial of fluorouracil-based chemotherapy regimens plus radiotherapy in postoperative adjuvant rectal cancer: GI INT 0144.

PURPOSE: Adjuvant chemoradiotherapy after or before resection of high-risk rectal cancer improves overall survival (OS) and pelvic control. We studied three postoperative fluorouracil (FU) radiochemotherapy regimens. PATIENTS AND METHODS: After resection of T3-4, N0, M0 or T1-4, N1, 2M0 rectal adenocarcinoma, 1,917 patients were randomly assigned to arm 1, with bolus FU in two 5-day cycles every 28 days before and after radiotherapy (XRT) plus FU via protracted venous infusion (PVI) 225 mg/m2/d during XRT; arm 2 (PVI-only arm), with PVI 42 days before and 56 days after XRT + PVI; or arm 3 (bolus-only arm), with bolus FU + leucovorin (LV) in two 5-day cycles before and after XRT, plus bolus FU + LV (levamisole was administered each cycle before and after XRT). Patients were stratified by operation type, T and N stage, and time from surgery. RESULTS: Median follow-up was 5.7 years. Lethal toxicity was less than 1%, with grade 3 to 4 hematologic toxicity in 49% to 55% of the bolus arms versus 4% in the PVI arm. No disease-free survival (DFS) or OS difference was detected (3-year DFS, 67% to 69% and 3-year OS, 81% to 83% in all arms). Locoregional failure (LRF) at first relapse was 8% in arm 1, 4.6% in arm 2, and 7% in arm 3. LRF in T1-2, N1-2, and T3, N0-2 primaries who received low anterior resection (those most suitable for primary resection) was 5% in arm 1, 3% in arm 2, and 5% in arm 3. CONCLUSION: All arms provide similar relapse-free survival and OS, with different toxicity profiles and central catheter requirements. LRF with postoperative therapy is low, justifying initial resection for T1-2, N0-2 and T3, and N0-2 anterior resection candidates.

Phase II trial of PN401, 5-FU, and leucovorin in unresectable or metastatic adenocarcinoma of the stomach: a Southwest Oncology Group study.

From February, 2001 to September, 2002, the Southwest Oncology Group (SWOG) accrued 65 patients with advanced gastric adenocarcinoma to a phase II trial of weekly 5-FU, leucovorin, and the orally-administered uridine analog PN401. Of these 65 patients, 57 were assessable for survival and toxicity, which were the endpoints for the study. Treatment consisted of the administration of 1200 mg/m(2) of 5-FU, 500 mg/m(2) of leucovorin, and 6 grams of PN401 every 8 h, beginning 8 h after the completion of the 5-FU infusion, and continuing for a total of 8 doses (48 grams) during each weekly chemotherapy session. Therapy was delivered for six weeks out of every 8-week treatment cycle. The gastrointestinal toxicity of this regimen was mild with 2 patients experiencing grade 3 stomatitis, and 6 patients having grade 3 diarrhea; and the hematologic toxicity was acceptable with 6 of 57 patients found to have had grade 3 or 4 leukopenia, and 14 of 57 patients experiencing grade 3 or 4 neutropenia. There were two deaths judged possibly related to treatment; one in a patient who experienced a variety of Grade 2 gastrointestinal toxicities and died at home with an unknown cause of death; and a second patient who also died at home, and for whom treatment-related sepsis could not be ruled out. The overall median survival was 7.2 months. The ability to safely deliver twice the usual dose of 5-FU with leucovorin on a weekly schedule suggests that oral uridine analog supplementation with PN401 may enhance the therapeutic index of the fluoropyrimidines.

Phase II trial of R115777 (NSC #70818) in patients with advanced colorectal cancer: a Southwest Oncology Group study.

PURPOSE: The purpose of this Phase II multi-institutional trial was to determine the efficacy and toxicity of R115777 in previously untreated patients with metastatic colorectal carcinoma. PATIENTS AND METHODS: Patients were required to have histologically confirmed colorectal cancer with distant metastatic disease that was not surgically curable. They could not have received prior chemotherapy for metastatic disease. R115777 was given at a dose of 300 mg p.o. twice a day for 21 days every 28 days until tumor progression or toxicity or other reason for discontinuation occurred. The primary endpoint was to determine the confirmed response probability with this treatment. RESULTS: There were 55 eligible patients accrued to the study. There were no complete responses, but one confirmed partial response for a confirmed response probability of 2% (95%CI 0-10%). Three additional patients had an unconfirmed partial response for an overall response probability of 7%. The time to treatment failure was 1.7 months and the estimated median survival was 8.1 months. One patient died of treatment related infection and there were 7 other patients with grade 4 toxicities consisting of neutropenia, leukopenia, febrile neutropenia and thrombocytopenia, depression, increased bilirubin, anemia, and pneumonitis/infiltrates. CONCLUSION: R115777 given as a single agent by this dose and schedule is ineffective in patients with metastatic colorectal cancer.

Impact of the year 2000 Medicare policy change on older patient enrollment to cancer clinical trials.

PURPOSE: A prior analysis by the Southwest Oncology Group (SWOG) showed that women and African American patients were adequately represented on cancer clinical treatment trials but that older patients were substantially underrepresented. Twenty-five percent of patients > or = 65 years old were enrolled onto SWOG trials from 1993 to 1996, whereas 63% of all patients with cancer were > or = 65 years old. Recognition of this under-representation led to a change in Medicare policy in 2000 to include coverage of routine patient care costs of clinical trials. We conducted an updated analysis of accrual trends. METHODS: The proportions of enrollment onto SWOG treatment trials by sex, race/ethnicity, and age (> or = 65 years) were computed for the years 1997 to 2000; corresponding rates in the United States were derived from US Census and National Cancer Institute Surveillance, Epidemiology, and End results data. Additionally, method of payment data were analyzed over time (1993 to 2003) to assess whether patterns in method of payment changed with the new Year 2000 Medicare policy on clinical trials coverage. RESULTS: The results showed continued adequate representation by sex and race/ethnicity. Older patient accrual on SWOG trials increased significantly since 2000, with 31% of patients > or = 65 years old enrolled from 1997 to 2000 and 38% enrolled from 2001 to 2003 (v 25% from 1993 to 1996). The percentage of patients using Medicare plus supplemental insurance also increased beginning in 2000, whereas the percentage of patients using Medicare alone remained the same. CONCLUSION: Method of payment analyses provided evidence that the Year 2000 Medicare policy change had a positive impact, but only for those patients with supplemental private coverage of coinsurance costs. Improvements in the Medicare payment structure could further increase older patient participation in clinical trials.