Gastrointestinal Cancer

In clinical trials of panitumumab (Vectibix), 8% to 13% of patients with refractory colorectal cancer achieved a partial tumor response with the drug, according to data from five studies reviewed at the 2006 Gastrointestinal Oncology Conference. The meeting was sponsored by the International Society of Gastrointestinal Oncology.

Industry and government need to form a new alliance to more efficiently conduct clinical trials, Howard Hochster, MD, professor of medicine, New York University Medical Center, said at the 2006 Gastrointestinal Oncology Conference, sponsored by the International Society of Gastrointestinal Oncology.

Two of the hottest targets in colorectal cancer are spurring "lots of enthusiasm," Lee M. Ellis, MD, professor of surgical oncology and cancer biology, The University of Texas M.D. Anderson Cancer Center, said at the 2006 Gastrointestinal Oncology Conference, sponsored by the International Society of Gastrointestinal Oncology. The two targets, c-Src and urokinase plasminogen activator receptor (uPAR), both play key roles in tumor metastases and migration.

In a phase I study, the chimeric monoclonal antibody, RAV12 (Raven biotechnologies inc) has shown preliminary evidence of efficacy in gastrointestinal (GI) tumors. Howard A Burris III, MD, director of drug development at the Sarah Cannon Cancer Center, Nashville, one of three centers where the trial is underway, spoke about the research at the Chemotherapy Foundation Symposium XXIV

Roche announced that a large, international phase III study (NO16966) enrolling 2,035 previously untreated metastatic colorectal cancer patients met both of its primary endpoints.

Colorectal cancer is the second most common cause of cancer death in the United States. It is estimated that about 55,000 patients will die this year due to advanced colorectal cancer. These grim statistics persist despite a marked increase in the rate of screening colonoscopies and improvements in adjuvant chemotherapy. Successful chemoprevention strategies may reduce the risk of new colorectal cancers, thus decreasing related overall morbidity and mortality.

Sunitinib malate (Sutent)is an effective treatment option forpatients with gastrointestinal stromal tumor(GIST) after imatinib mesylate(Gleevec) therapy has failed, accordingto a multicenter, randomized, placebocontrolledphase III clinical trial.

Gleevec (imatinib mesylate) tablets has receivedFDA approval to treat patients with fiverare, potentially life-threatening disorders,representing the first time that aregulatory authority has ever simultaneouslyapproved one targeted medicinefor so many disorders, according toNovartis, maker of Gleevec.

A phase III trial has shown that XELOX is as effective as FOLFOX4 in patients with metastatic colorectal cancer, and that adding the targeted agent bevacizumab (Avastin) to either regimen improves progressionfree survival (PFS).

The science supporting molecularly targeted therapies for the treatment of patients with solid tumors continues to evolve. Nurses are challenged to understand cell signaling, molecular targeting, and the mechanism of action of targeted agents. Two cell signal transduction pathways regulate the development, proliferation, and metastasis of solid tumors: the human epidermal growth factor (HER) receptor pathway and the vascular endothelial growth factor (VEGF) receptor pathway. Several novel pharmacologic agents with distinct indications and methods of administration target the HER and VEGF molecular pathways.

Following priority review, the US Food and Drug Administration (FDA) has approved Amgen Inc's panitumumab (Vectibix) for the treatment of advanced colon cancer.

Colorectal cancer is the second leading cause of cancer-related death (after lung/bronchus cancer) in the United States.[1] In 2002, a total of 139,534 adults in the United States had colorectal cancer diagnosed, and 56,603 died. The US Preventive Services Task Force and other national organizations recommend that adults aged ≥ 50 years be screened for colorectal cancer with one or more of the following tests: fecal occult blood testing (FOBT) every year, sigmoidoscopy or double-contrast barium enema every 5 years, or colonoscopy every 10 years.

For metastatic colorectal cancer, the benefits of maintenance therapy with 5-FU/leucovorin appear questionable, according to results of the OPTIMOX2 study

In patients with resectable rectal cancer, routine short-course preoperative radiotherapy results in a significant reduction in local recurrence and improved disease-free survival, compared with a selective postoperative approach.

Improved compliance with imatinib (Gleevec) therapy for patients with chronic myeloid leukemia (CML) and gastrointestinal stromal tumors (GIST) is associated with decreased total and disease-related health care costs

Nearly 150,000 people will be diagnosed with colorectal cancer in the United States in 2006. The impact of this diagnosis will be felt by countless family members, coworkers, and friends. Although screening tests for colorectal cancer have been available and encouraged by medical associations such as the American Cancer Society (ACS) and others, public awareness and compliance has been dismal.

The liver is a frequent site of metastatic colorectal disease. Over the past 20 years, improvements in systemic chemotherapy and surgical techniques have improved the survival of patients with hepatic metastases. For 4 decades, fluorouracil and leucovorin were the only drugs available to treat metastatic colorectal cancer, but several new drugs and a variety of novel regimens are now available. Further improvements in results have been seen with the delivery of chemotherapy via the hepatic artery. Surgical resection of liver metastases has been encouraged when possible, and recent advances in surgery such as portal vein embolization, have made liver resection a possibility for more patients. This review considers the timing and sequence of chemotherapy and surgery in this setting, as well as the roles of cryoablation, radiofrequency ablation, and radiation therapy.

The liver is a frequent site of metastatic colorectal disease. Over the past 20 years, improvements in systemic chemotherapy and surgical techniques have improved the survival of patients with hepatic metastases. For 4 decades, fluorouracil and leucovorin were the only drugs available to treat metastatic colorectal cancer, but several new drugs and a variety of novel regimens are now available. Further improvements in results have been seen with the delivery of chemotherapy via the hepatic artery. Surgical resection of liver metastases has been encouraged when possible, and recent advances in surgery such as portal vein embolization, have made liver resection a possibility for more patients. This review considers the timing and sequence of chemotherapy and surgery in this setting, as well as the roles of cryoablation, radiofrequency ablation, and radiation therapy.

Amgen announced interim results from two phase II studies of panitumumab, an investigational fully human monoclonal antibody that targets the epidermal growth factor receptor (EGFR). Results from both studies suggest that the antitumor activity of panitumumab was independent of tumor EGFR expression levels in patients with metastatic colorectal cancer who have failed standard chemotherapy.

The liver is a frequent site of metastatic colorectal disease. Over the past 20 years, improvements in systemic chemotherapy and surgical techniques have improved the survival of patients with hepatic metastases. For 4 decades, fluorouracil and leucovorin were the only drugs available to treat metastatic colorectal cancer, but several new drugs and a variety of novel regimens are now available. Further improvements in results have been seen with the delivery of chemotherapy via the hepatic artery. Surgical resection of liver metastases has been encouraged when possible, and recent advances in surgery such as portal vein embolization, have made liver resection a possibility for more patients. This review considers the timing and sequence of chemotherapy and surgery in this setting, as well as the roles of cryoablation, radiofrequency ablation, and radiation therapy.

FOLFIRI can be given intermittently in advanced previously untreated colorectal cancer, with survival rates and toxicity similar to continuous FOLFIRI

Patients with metastatic gastrointestinal stromal tumors (GIST) who are in complete remission after surgical resection remain at high risk for relapse and should continue long-term treatment with imatinib (Gleevec), according to Binh Nguyen Bui, MD, of Institut Bergonie, Bordeaux, France. Dr. Bui reported results of the French Sarcoma Group BFR14 randomized phase III trial at the American Society of Clinical Oncology 42nd Annual Meeting (abstract 9501).

In the first-ever phase III trial of oral capecitabine (Xeloda) as first-line treatment for gastric cancer, capecitabine plus cisplatin was found to be at least as effective and safe in achieving progression-free survival as the current standard of care for gastric cancer-intravenous fluorouracil (IV 5-FU) plus cisplatin—with higher overall response rates, according to final data presented at the 42nd Annual American Society of Clinical Oncology (ASCO) Annual Meeting in Atlanta.

Genentech Inc, recently announced that the US Food and Drug Administration (FDA) approved bevacizumab (Avastin) in combination with intravenous fluorouracil (5-FU)-based chemotherapy for second-line metastatic colorectal cancer.

Surgery for cancer carries concerns of tumor dissemination related to tumor manipulation, tumor violation, and wound seeding. Minimally invasive surgery is now standard for several benign conditions, such as symptomatic cholelithiasis and surgical therapy of gastroesophageal reflux. With the minimally invasive surgery explosion of the 1990s, virtually every procedure traditionally performed via laparotomy has been performed successfully with laparoscopic methods, including pancreaticoduodenectomy for cancer. Shortly after the first descriptions of laparoscopic-assisted colectomy, reports of port-site tumor recurrences surfaced, raising concerns of using pneumoperitoneum-based surgery for malignancy. This review covers the development of laparoscopic surgery for cancer. Historical perspectives elucidate factors that helped shape the current state of the art. Theoretical concerns are discussed regarding surgery-induced immune suppression and its potential effects on tumor recurrence with both open and laparoscopic approaches. The concerns of laparoscopic port-site wound metastases are addressed, with a critical evaluation of the literature. Finally, a technical discussion of laparoscopic-assisted resections of hepatic and pancreatic tumors details patient selection, operative approach, and existing data for these operations.

Confocal laser endomicroscopy, a new technology that permits high-resolution subsurface microscopic imaging of living tissue during routine endoscopy, can facilitate the diagnosis of esophageal and gastric cancers, according to a recent report. "Endomicroscopy allows you to make an in vivo histology during ongoing endoscopy," Ralf Kiesslich, MD, PhD, said at the 2006 Gastrointestinal Cancers Symposium (General Session I).

A higher, investigational starting dose of imatinib (Gleevec) significantly improved progression-free survival (PFS) in high-risk patients with advanced KIT-positive gastrointestinal stromal tumor (GIST) expressing the exon 9 mutation, according to a new analysis of an EORTC phase III trial. The trial compared imatinib at the standard dose of 400 mg/d vs 800 mg/d in patients with unresectable and/or metastatic GIST. Researchers analyzed pretreatment GIST samples for mutations from 377 patients in the trial.

An increasing body of evidence suggests that geriatric patients can benefit from and tolerate standard chemotherapy similarly to younger patients in the settings of both early- and advanced-stage colorectal cancer. Assessment of this unique population requires more comprehensive evaluation in addition to routine history, physical examination, and laboratory tests. Specific considerations of their physiologic functional changes will help physicians better manage these patients. Ongoing studies are now designed to better understand the decision-making process, safety profile, and efficacy of various treatment regimens in geriatric patients.

An increasing body of evidence suggests that geriatric patients can benefit from and tolerate standard chemotherapy similarly to younger patients in the settings of both early- and advanced-stage colorectal cancer. Assessment of this unique population requires more comprehensive evaluation in addition to routine history, physical examination, and laboratory tests. Specific considerations of their physiologic functional changes will help physicians better manage these patients. Ongoing studies are now designed to better understand the decision-making process, safety profile, and efficacy of various treatment regimens in geriatric patients.

An increasing body of evidence suggests that geriatric patients can benefit from and tolerate standard chemotherapy similarly to younger patients in the settings of both early- and advanced-stage colorectal cancer. Assessment of this unique population requires more comprehensive evaluation in addition to routine history, physical examination, and laboratory tests. Specific considerations of their physiologic functional changes will help physicians better manage these patients. Ongoing studies are now designed to better understand the decision-making process, safety profile, and efficacy of various treatment regimens in geriatric patients.