Click here to view as PDF.American Association for Cancer Research
Translating the Latest Discoveries Into Cancer Prevention and Cures
The American Association for Cancer Research (AACR), Philadelphia, is considered the world’s oldest and largest oncology-related scientific organization. Currently celebrating its centennial, the AACR recently held its 100th annual meeting at the San Diego Convention Center from April 12–16, 2008. According to its organizers, the meeting focused on five key areas: (1) basic science, (2) translational medicine, (3) clinical research, (4) survivorship, and (5) prevention.
In a welcome letter to participants, William N. Hait, MD, PhD, President, AACR, and Eileen P. White, PhD, Chairperson, 2008 Program Committee, AACR, described the meeting as a “comprehensive scientific program that features the foremost breakthroughs in laboratory, translational, and clinical cancer research.” A full schedule of more than 250 educational sessions, plenary sessions, and scientific symposia were led by a roster of speakers that Drs. Hait and White characterized as “top scientists discussing innovative research approaches, novel technologies, life-saving therapies in the pipeline, clinical trials, and new approaches to cancer prevention.”
Various poster sessions featuring more than 6,000 abstracts of breaking clinical research, opinion-leader roundtable discussions, networking events, and a major exhibition of vendor exhibits (including pharmaceutical manufacturers, medical device concerns, biotechnology companies, health care publishers, patient advocacy organizations, and managed care companies) rounded out the slate of activities that AACR participants engaged in.
More than 15,000 participants representing more than 60 countries from around the globe attended the meeting. These included practicing oncologists, oncology fellows, scientists, researchers, academicians, key opinion leaders and other cancer care professionals (i.e., nurses, physician assistants, pharmacists, administrators) as well as patient group, physician group, employer group, and government agency representatives. The following sections provide a general overview of breaking news and session highlights from the conference.
Meeting Highlights and Breaking News
According to an AACR spokesperson, significant research news in the realms of both liver and ovarian cancer was unveiled during the meeting.â–ºLiver Cancer
Sunitinib Monotherapy in Advanced Hepatocellular Carcinoma Yields Evidence of Antitumor Activity
According to the results of a multidisciplinary phase II trial, sunitinib (Sutent) may slow the growth and the spread of liver cancer. A team of researchers from the Boston-based Massachusetts General Hospital Cancer Center asserted that treatment with sunitinib slows tumor growth and reduces the risk of metastasis in patients with hepatocellular carcinoma, a particularly aggressive form of liver cancer.
In the study, researchers enrolled 34 patients with advanced liver cancer who were dosed with 37.5 mg sunitinib daily over the course of a standard six-week regimen (4 wk on therapy, followed by 2 wk off therapy). After 12 weeks, one patient had a partial response (PR) and 17 patients had stable disease (SD). The median progression-free survival (PFS) was four months and the median overall survival (OS) was 10 months.
“Results are still preliminary, but there is clear evidence of an antitumor activity in these patients,” stated lead investigator Andrew X. Zhu, MD, PhD, Massachusetts General Hospital Cancer Center. Dr. Zhu and colleagues also measured changes in tumor vascular permeability using MRI, because the abnormally increased leakage of plasma from blood vessels in tumors is causally related to pathways blocked by sunitinib. They found that mean tumor permeability decreased after treatment with sunitinib by 40%, compared with measures taken at the start of the study.
Circulating progenitor cells (CPCs), a potential measure of the risk of whether or not cancer will spread, were also reduced with sunitinib treatment. The number of CPCs was significantly decreased by sunitinib at days 15, 29, and 57, compared with baseline (P
< 0.01). Dr. Zhu noted that an increase in CPCs during treatment appears to be associated with significantly increased mortality.
Researchers reported that the treatment was associated with a high degree of tolerability. Blood disorders such as neutropenia (12% of patients), lymphopenia (15%), thrombocytopenia (12%), and hyperbilirubinemia (6%) occurred at low rates. Fatigue was observed in 9% of patients and hand–foot syndrome in 6% of patients.
“Patients with this type of liver cancer have a very poor prognosis and the only currently available therapy is sorafenib (Nexavar). This study shows that we may be able to effectively use sunitinib with manageable side effects. Giving these patients more options would have a significant impact,” explained Dr. Zhu.
Hepatocellular carcinoma is a cancer that relies heavily on blood vessels for growth. According to Dr. Zhu, sunitinib controls the growth of blood vessels and could therefore potentially play an important role in treatment.