The war against cancer gathered steam in 2008, as new drugs tackled the toughest cancers with some success, and advances were made in both disease prevention and risk factor identification.
A new report from the American Society of Clinical Oncology (ASCO) details 12 "major" advances and 19 "notable advances" across the gamut of cancer prevention, screening, treatment and survival in the past year.
"These specific advances . . . reflect a maturation, if you will, of the whole approach of personalised medicine to oncology care," said ASCO President Dr Richard L. Schilsky, a professor of medicine at the University of Chicago Medical Centre. "And some of the reports deal with targeted therapies being used in a broader array of diseases. We're beginning to see the utility of targeted therapies expand across many, many diseases, and we're increasingly able to identify those patients who are most likely to benefit from those targeted therapies."
One of the most impressive reports of the year serves as a backdrop to these advances, pointed out Dr Jay Brooks, chairman of haematology/oncology at Ochsner Health System in Baton Rouge, US. That was a study showing the first reported decline in the number of US men and women developing and dying from cancer.
Nevertheless, some 1.4 million people received the devastating diagnosis of cancer in 2008, and half a million people died from the disease.
Following are the 12 major advances of 2008 identified by ASCO, divided into six general areas and not ranked in order of importance.
In the area of hard-to-treat cancers:
- Cetuximab (Erbitux), a monoclonal antibody, when added to chemotherapy, increased overall survival by as much as 21% in patients with non-small cell lung cancer which expressed the epidermal growth factor receptor (EGFR). Patients receiving Erbitux in a recent trial lived an average of 11.3 months vs. 10.1 months in those receiving a placebo. Lung cancer is the number-one cancer killer among men and women; only 5% of those diagnosed with this type of lung cancer survive five years.
- The new chemotherapy drug Gemcitabine (Gemzar) doubled disease-free survival from 6.9 months to 13.4 months in pancreatic cancer patients, and increased overall survival from 20.2 months to 22.8 months in patients with early-stage pancreatic cancer who had undergone surgery. Again, only 5% of people receiving this diagnosis live five years.
In the area of new drug approvals:
- Bendamustine (Treanda) "eliminated" chronic lymphocytic leukaemia (CLL) in one-third of patients compared with 2% who went with current standard therapy, and extended survival without a recurrence to 21.7 months from 9.3 months. The drug was approved in March of 2008 and is now indicated as first-line treatment for the disease.
- Bevacizumab (Avastin), another monoclonal antibody, was approved (in conjunction with the chemotherapy drug paclitaxel (Taxol) for women with previously untreated HER2-negative, metastatic breast cancer. A trial the year before had found the combination doubled disease-free survival compared with women receiving chemo alone. A second trial, this one from 2008, confirmed the findings.
In the area of reducing cancer recurrence:
- Women with breast cancer who have already taken tamoxifen for five years, and who take additional hormone therapy in the form of an aromatase inhibitor or more tamoxifen may reduce even further the chances of the cancer coming back.
- Adding the osteoporosis drug zoledronic acid (Zometa) in premenopausal women with early-stage breast cancer also undergoing suppression of ovarian function and hormonal therapy with tamoxifen or an aromatase inhibitor, reduced the risk of recurrence.
- Giving one year of pegylated interferon treatment to people with stage III melanoma who had already undergone surgery reduced the risk of recurrence by 18%; the four-year recurrence-free survival rate for those on interferon was 45.6% vs. 38.9% for those not taking the treatment. Overall survival was the same.
In the area of personalised medicine:
- Patients with newly diagnosed advanced colorectal cancer who have the normal version of the KRAS gene benefited from Erbitux, according to a study released last year. Those with a mutation in the gene did not benefit, a finding which will help guide treatment.
In the area of risk factors:
- Women who take birth control pills reduce their risk for ovarian cancer by 20% for every five years they are on the pill.
- Between 1973 and 2004, the incidence of head-and-neck cancers related to the HPV virus increased by 0.8%. The incidence of these cancers not associated with HPV stayed the same, then declined during the same period. The increase could be due to changes in sexual behaviour, for example, an increase in oral sex.
In the area of access to care:
- A significant shortage of oncologists in the United States (up to 4 000) is predicted by 2020, even as the number of cancer patients will continue to rise.
- Childhood cancer survivors are up to 10 times more likely than their healthy siblings to develop heart disease 30 years after their initial cancer, although researchers emphasised that the absolute rates were still low.
The report also included two recommendations: Increase funding for clinical cancer research and boost the number of participants in clinical trials, which hovers at around 5% of all adult cancer patients who could be participating in such trials.
"The good news is that we continue to make great progress in cancer," Schilsky said. "All of that is based upon the strength of our research programs in this country, which are now really beginning to suffer. We've had five years of essentially flat funding to the National Cancer Institute, which really translates into an approximate 15% decrease in the budget. At a time when we have more opportunity and are making more progress than ever, the government is essentially pulling the rug out from under us."
"There have been significant advances, [but] if you're a patient out there or have a loved one who has cancer, the results are still not satisfying," said Dr Otis Webb Brawley, chief medical officer for the American Cancer Society. "We have made definite positive steps, but they are steps. We haven't arrived." - (Amanda Gardner/HealthDay News)
Source: Journal of Clinical Oncology.