scout

Gastrointestinal Cancer

Latest News


CME Content


Gastrointestinal stromal tumors (GISTs) originate from the interstitial cells of Cajal or a precursor and are the most common mesenchymal neoplasms of the gastrointestinal (GI) tract.[1] Although GISTs often present as localized masses, they are typified by a high risk of metastatic relapse, most commonly in the liver and peritoneum.

Prior to the publication of the German CAO/ARO/AIO 94 trial, the conventional adjuvant approach for patients with clinically resectable, ultrasonographically diagnosed T3 (uT3) and/or node-positive rectal cancer was initial surgery and, if pathologically confirmed T3 (pT3) and/or node-positive, postoperative combined chemotherapy plus radiation. The German trial confirmed that compared to postoperative therapy, the preoperative approach was associated with significantly lower local recurrence rates, less acute and chronic toxicity, and an increased incidence of sphincter preservation.

In a change from its previous recommendation, the US Preventive Services Task Force now recommends that adults aged 50 to 75 be screened for colorectal cancer using annual high-sensitivity fecal occult blood testing, sigmoidoscopy every 5 years with fecal occult testing between sigmoidoscopic exams, or colonoscopy every 10 years. According to the Task Force, good evidence exists that using these methods save lives.

Surgical resection offers the only potential cure for pancreatic adenocarcinoma. Unfortunately, while perioperative outcomes have improved dramatically in recent years, few patients present with tumors that are amenable to resection, and even after resection of apparently localized disease, long-term survival is poor.

Sorafenib is indicated for the treatment of patients with advanced renal cell cancer, and patients with unresectable hepatocellular cancer. Sunitinib is indicated for the treatment of patients with advanced renal cell cancer, and patients with gastrointestinal stromal tumor (GIST) after disease progression on imatinib mesylate (Gleevec).

Researchers from the Leeds Institute of Molecular Medicine at the University of Leeds assessed the quality of colon cancer surgery and noted that there was marked variability in the plane of surgery achieved in colon cancer.

Gemcitabine (Gemzar)-based regimens have been the mainstay of front-line treatment for patients who present with advanced pancreatic cancer over the past decade, but most medical oncologists throw their hands up in frustration when considering what therapeutic options a patient is left with once he or she has progressed beyond first-line therapy. This is not without reason-as nicely summarized in the review article by Almhanna and Kim, studies in the published medical literature focusing on treatment of pancreatic cancer in the salvage setting have generally been small and have shown very modest clinical efficacy, characterized by low response rates and progression-free survival of a few months at best.

Pancreatic cancer is the fourth leading cause of cancer mortality in the United States. According the American Cancer Society, about 37,680 new cases are anticipated in the year 2008, and 34,290 patients will die from the disease.[1] This malignancy is a very aggressive tumor, and patients often present with advanced-stage disease. Surgical resection, when possible, provides the only opportunity for cure. Even with R0 resection, pancreatic cancer still carries an overall dismal prognosis, and therefore adjuvant treatment is offered.

The paper by Almhanna and Kim addresses a clinical dilemma in the treatment of pancreatic cancer, for which no standard currently exists. The review article concisely summarizes studies in the second-line setting that have been conducted to date, many of which have been published only in abstract form. The authors organize the studies into tables according to the number of agents in the trials and highlight the response rates and toxicities. The inclusion of study endpoints (both primary and secondary) would have made the tables more informative. In the article, the studies are organized according to the specific agent studied. Several of the studies continue to use gemcitabine (Gemzar) in combination with other agents in the second-line setting, but we have insufficient data to determine that continuing gemcitabine in this setting is worthwhile.

CHICAGO-Two new agents-an inhibitor of heat shock protein 90 and an inhibitor of insulin-like growth factor 1 receptor-appear promising for treating gastrointestinal stromal tumors that are resistant to available tyrosine kinase inhibitors, researchers said at ASCO 2008.

Caris Diagnostics (Caris Dx), a provider of diagnostic, translational development and pharmaceutical services encompassing anatomic pathology and molecular testing, announced that it is now offering KRAS mutation analysis, designed to provide information on which colon cancer patients are most likely to respond to cetuximab (Erbitux), comarketed by ImClone and Bristol-Myers Squibb, or panitumumab (Vectibix) developed by Amgen.

CHICAGO-Sorafenib (Nexavar) is safe and prolongs overall survival and time to progression in Asian patients with advanced hepatocellular carcinoma (HCC), finds the randomized phase III Asia-Pacific liver cancer study. Moreover, efficacy was similar to that in the Western population even though the Asian patients had more adverse prognostic factors.

In this issue of ONCOLOGY, Drs. Patel, Puthillath, Yang, and Fakih discuss the evolution of adjuvant therapy for locally advanced rectal cancer from postoperative to preoperative radiation and provide a fairly comprehensive review of the data on adjuvant/neoadjuvant chemoradiation for rectal cancer. The authors then attempt to critically evaluate the use of combination chemotherapy regimens in the neoadjuvant setting, asking the question, “Is more better?”

Neoadjuvant chemoradiation has become the favored adjuvant treatment for stages II and III rectal cancer. Compared to postoperative chemoradiation, this modality of treatment has been shown to be superior in terms of toxicity, local relapse, and sphincter-saving.[1] This article will focus on the evolution of neoadjuvant chemotherapy over the past 2 decades, current acceptable neoadjuvant standards, and current investigational regimens.

A large, multicenter study has shown that the chemotherapy drug gemcitabine (Gemzar) more than doubles overall survival in patients who have undergone surgery for pancreatic cancer. The CONKO-001 trial is the first large-scaled phase III study to show a benefit for any chemotherapy agent given to early-stage pancreatic cancer patients after surgery to remove their tumors. The trial data were presented by Hanno Riess, md, phd, a professor at Charité University Medical School in Berlin and the leader of the CONKO study group (abstract LBA4504).