Cancer Therapy Center

A recent study has shown that fierfighters are more likely to develop many types of cancer, specifically testicular, non-Hodgkin’s lymphoma, prostate, and myeloma, when compared to cancer rates among the general population. Experts recommended that firefighters should take precautions when fighting fires, particularly if they’ve removed their protective gear or breathing apparatus, as exposure to carcinogenic toxins occur around (but not necessarily in) the fire area.

The study, which will appear in the November issue of Journal of Occupational and Environmental Medicine, used existing data from over 110,000 firefighters and 32 previous studies to analyze rates of 20 different cancers. Experts concluded that long term exposure to carcinogens such as benzene, diesel exhaust, chloroform, soot, styrene, and formaldehyde - chemicals that can be inhaled or absorbed through the skin - caused a significant increase in risk.

Notably, the risk of testicular cancer increased 100% for firefighters, with multiple myeloma and non-Hodgkin’s lymphoma both having a 50% increase in risk, and a 28% increase in risk for prostate cancer.

WASHINGTON (Reuters) - Hormone therapy used to treat prostate cancer that has already spread may save patients from cancer but raise the risk of diabetes and heart disease, U.S. researchers reported on Tuesday.

They said doctors need to monitor such men closely to make sure they do not trade one cause of death for another.

“Men with prostate cancer have high five-year survival rates, but they also have higher rates of noncancer mortality than healthy men,” Dr. Nancy Keating, an assistant professor of health care policy and medicine at Harvard Medical School, who led the study, said in a statement.

“This study shows that a common hormonal treatment for prostate cancer may put men at significant risk for other serious diseases. Patients and physicians need to be aware of the elevated risk as they make treatment decisions.”

Writing in the Journal of Clinical Oncology, Keating and colleagues said they examined the records of 73,000 men age 66 or older who were diagnosed with local or regional prostate cancer.

Men with early prostate cancer can be treated surgically, with radiation or with radioactive seeds implanted carefully around the prostate.

If the cancer has spread, they are often treated to block production of the hormone testosterone, which can fuel prostate cancer.

This is done either by removal of the testes, or more commonly, by regular injections of a gonadotropin-releasing hormone or GnRH agonist drug.

“Our study found that men with local or regional prostate cancer receiving a GnRH agonist had a 44 percent higher risk of developing diabetes and a 16 percent higher risk of developing coronary heart disease than men who were not receiving hormone therapy,” Keating said.

“For men who do require this treatment, physicians may want to talk with their patients about strategies, such as exercise and weight loss, which may help to lower risk of diabetes and heart disease,” Dr. Matthew Smith of Massachusetts General Hospital said in a statement.

Prostate cancer is the most common cancer among men, with more than 234,000 new cases diagnosed in the United States every year. It will kill 27,350 this year, according to the American Cancer Society.

On Tuesday, the Prostate Cancer Coalition released a report showing that deaths from prostate cancer have fallen by 32.5 percent in 10 years in the United States.

It said the mortality rate for black men is the lowest since 1977, but it is still 2.36 times the rate for white men.

The mortality rate was 39.34 per 100,000 in 1993 and dropped to 26.55 per 100,000 in 2003, mostly due to better screening but also because of better treatments, according to the coalition and the American Cancer Society.

Lung cancer patients treated with an experimental new drug in addition to standard chemotherapy lived more than one third longer than patients treated with chemotherapy alone, according to new data posted at 2Breathe.net, as they review a small phase II study carried out by a British biotech company, Antisoma plc, enrolled 70 patients with non-small cell lung cancer, the most common type of lung cancer. 

Researchers reported that patients treated with AS1404 on top of standard chemotherapy lived 14 months compared to 8.8 month for patients who solely received chemotherapy alone.

AS1404 is one of a new class of drugs called Vascular Disrupting Agents (VDAs) that work by selectively destroying established tumor blood vessels, the blood supply that enables a tumor to survive and grow.

Researchers said AS1404 is able to distinguish between the tumor’s blood supply and the more permeable and less-well organized capillary network of healthy organs.

If the early results with AS1404 are confirmed in larger phase III trials, this would be a significant increase in life expectancy for patients suffering from lung cancer, which has one of the lowest survival outcomes of any cancer.

The referenced study is one of three currently underway testing various aspects of AS1404. Positive data has been announced in a trial testing its use in prostate cancer, as well as promising early data from an ongoing ovarian cancer trial. If approved for use, Antisoma is expected to license AS1404 to a number of different companies.

Forbes is one of many news outlets explaining a new Australian study that claims to have identified a genetic marker capable of identifying agressive prostate cancer.

“Men who have low levels of a marker called AZGP1 in the prostate at the time of [prostate removal] surgery have a greatly increased risk of developing metastatic cancer,” Sue Henshall, leader of the prostate cancer research group at the Garvan Institute in Sydney, said in a prepared statement.

“This means two things: that these men could benefit from more aggressive treatment such as radiotherapy or chemotherapy around the time of surgery when they still have potentially curable cancer; and that patients with a low risk of developing metastatic disease will have the option of deferring treatments that have a negative impact on quality of life,” Henshall added.

The study authors suggest that a follow-up study to determine the association between AZGP1 levels and metastatic cancer in prostate cancer patients who have not had surgery is the next step.

Results from the largest study of men with prostate cancer treated with high-dose, intensity modulated radiation therapy (IMRT) show that the majority of patients remain alive with no evidence of disease after an average follow-up period of eight years. The 561 prostate cancer patients treated with IMRT at Memorial Sloan-Kettering Cancer Center were classified into prognostic risk groups. After an average of eight years, 89 percent of the men in the favorable risk group were disease-free and none of the men in any group developed secondary cancers as a result of the radiation therapy. This report, published in the October 2006 issue of The Journal of Urology, is the first description of long-term outcomes for prostate cancer patients using IMRT.

“Our results suggest that IMRT should be the treatment of choice for delivering high-dose, external beam radiotherapy for patients with localized prostate cancer,” said Dr. Michael J. Zelefsky, Chief of the Brachytherapy Service at Memorial Sloan-Kettering. “We were able to show long-term safety and long-term efficacy in a very diverse group of prostate cancer patients that we followed - many for as long as ten years. Despite the fact that some patients had an aggressive form of their disease with high Gleason scores and PSA (prostate specific antigen) levels, the overwhelming majority of patients had good tumor control with neither recurrence of their original cancer nor development of second cancers, which one might have expected from the high doses of radiation,” he added. Pre-treatment diagnostic evaluations were performed for all of the patients to better define their clinically localized prostate cancer. They were classified into prognostic risk groups as defined by the National Comprehensive Cancer Network guidelines (www.nccn.org). These are based on clinical characteristics including age, T stage, Gleason score, PSA level, and pre-treatment with neoadjuvant androgen deprivation.

Between April 1996 and January 2000, 561 patients with a median age of 68 (ranging from 46 to 86 years old) were treated with IMRT, an improved form of three-dimensional conformal radiation therapy (3D-CRT), also used in radiotherapy. IMRT uses enhanced planning treatment software that more precisely targets the prostate, allowing the beam of radiation to deliver a high dose (81 Gy) to the tumor target while sparing the adjacent bladder and rectum from exposure to the higher amounts of radiation. Perhaps because of this, the eight-year results show urinary continence was maintained for all patients, and only 1.6 percent of the five hundred sixty-one patients experienced rectal bleeding. The high-dose radiotherapy was curative for the majority of the patients in all three prognostic risk groups, with 89 percent of the favorable, 78 percent of the intermediate, and 67 percent of the unfavorable group alive after an average period of eight years. Of those men who were potent prior to IMRT, erectile dysfunction developed in 49 percent.

“This study confirms that we can improve patients’ quality of life by reducing the side effects of radiotherapy while maintaining disease-free survival,” said Dr. Zelefsky. “However, there is still room for improvement. We are incorporating image-guided approaches that may continue the excellent tumor control but further limit the area we are irradiating and reduce side-effects.”

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The study’s co-authors are Heather Chan, Margie Hunt, Yoshiya Yamada, MD, Alison M. Shippy, and Howard Amols, PhD, of Memorial Sloan-Kettering.

Memorial Sloan-Kettering Cancer Center is the world’s oldest and largest institution devoted to prevention, patient care, research, and education in cancer. Our scientists and clinicians generate innovative approaches to better understand, diagnose, and treat cancer. Our specialists are leaders in biomedical research, and in translating the latest research to advance the standard of cancer care worldwide.

Contact: Joanne Nicholas
Memorial Sloan-Kettering Cancer Center