Advances in cancer screening, treatments aid patients
Cancer claimed an estimated 565,000 lives in the United States in 2008, making it the second most common cause of death in the nation. The American Cancer Society estimated that 1.4 million new cases of cancer would be diagnosed in 2008, led by prostate cancer in men and breast cancer in women, followed by lung and colorectal cancer in both genders.
The good news is that the five-year survival rate for patients with all cancers diagnosed from 1996-2003 was 66 percent, up from 50 percent from 1975-1997. The ACS, which has declared April as Cancer Control Month, attributes this to better screenings, as well as treatment advances that contribute to improved survival rates, and enhanced quality of life for cancer patients.
Improvements in screening, diagnosis, and treatment can also be seen in cancer-related claims paid by the AVMA Group Health and Life Insurance Trust, which declined from $10.9 million in 2007 to $7.8 million in 2008 for treatment of malignant cancers.
Advances in screening and treatment
Most recently, researchers announced development of a new genetic test that could result in faster, more immediate treatment for patients. It identifies four types of breast cancer.
In the study, published online Feb. 9, 2009, in the Journal of Oncology, researchers at Washington University in St. Louis analyzed the gene activity of more than 1,000 breast tumors and pinpointed 50 genes that could be used to identify the four types of breast tumors: luminal A, luminal B, HER2-enriched, and basal-like.
The test is also the first to incorporate a molecular profile for basal-like cancer, the most aggressive form of breast cancer and the most sensitive to chemotherapy.
Findings of several recent studies on the treatment of genitourinary cancers were also released in February. One study found that a novel molecular urine test that detects the fusion of two genes, TMPRSS2 and ERG, was highly accurate for detecting prostate cancer and may help identify cancers that are likely to grow and spread quickly.
A second study found that positron emission tomography scanning is more accurate than computed tomography or magnetic resonance imaging for determining the extent of disease in patients with suspected metastatic bladder cancer.
Interim results from a phase III study indicate that a five-week course of radiation therapy with higher doses was just as effective, and as well-tolerated, as standard, seven-and-a-half-week radiation therapy for reducing the risk of prostate cancer recurrence.
Other significant research findings in the past year include these:
- Abnormal white blood cells can be present in patients' blood more than six years prior to the diagnosis of a chronic form of lymphocytic leukemia. This study, published in the Feb. 12, 2009, issue of the New England Journal of Medicine, may lead to a better understanding of the cellular changes that characterize the earliest stages of the disease and how it progresses.
- A molecule produced by the body's metabolism could be used to differentiate benign prostate tissue from localized and metastatic prostate cancer. The molecule, sarcosine, may also be associated with prostate cancer invasiveness and aggressiveness, and may be an excellent indicator of cancer progression. The findings were published in the Feb. 12, 2009, issue of Nature.
- Identification of mutations in a gene that predict a high likelihood of relapse in children with acute lymphoblastic leukemia could provide the basis for future diagnostic tests to assess the risk of treatment failure. The findings were published in the Jan. 29, 2009, issue of the New England Journal of Medicine.
- Development of an experimental biomarker test could detect prostate cancer more accurately than any other screening method currently in use. The simple urine test accurately identified 80 percent of patients who were later found to have prostate cancer. The study appeared in the February 2008 issue of Cancer Research.
Prevention is the best medicine
Individuals, too, have a role in the fight against cancer. In addition to maintaining a healthy weight, following a healthy diet, and leading a physically active lifestyle, the ACS recommends regular screenings for those with an average risk for cancer. The AVMA GHLIT has a Wellness Benefit on a number of medical plans to encourage veterinarians to be more proactive about their health.
Beginning at age 20, men and women should have regular checkups that include health counseling and, depending on age and gender, examinations for cancers of the thyroid gland, oral cavity, skin, lymph nodes, testes, and ovaries, as well as for some nonmalignant cancers. Regular screenings for colorectal cancer should begin at age 50. This includes noninvasive blood and stool testing, which should be done annually, and procedures, such as colonoscopy, to detect colorectal cancer and polyps, which is recommended every five years.
Beginning in their 20s, women should have annual cervical cancer screenings with a regular Pap test (or every two years with new, liquid-based Pap tests) and annual clinical breast examinations. Mammograms and clinical breast examinations are recommended annually beginning at age 40.
For men, prostate-specific antigen blood tests and digital rectal examinations of the prostate gland are recommended annually, beginning at age 50.
Individuals at high risk for cancer should consult with their physician for recommendations regarding types and frequency of screenings.