This week we report research on the dangers of drinking green tea during treatment with the cancer drug Velcade, improvements choosing patients for successful surgery to remove liver mets, and the failure of lidocaine patches to reduce persistent surgical incision pain.
We also include news stories about potential FDA restrictions on Darvon, plums as a new “superfruit”, and a new microwave ablation treatment for liver tumors.
Brief Research Reports
- An ingredient in green tea blocks the cancer-fighting action of Velcade, a drug used to treat multiple myeloma. Expecting to find that polyphenols in the tea enhanced chemotherapy, scientists at the University of California at Los Angeles were surprised when molecules extracted from green tea formed a chemical bond with Velcade and destroyed its anticancer action in mice. Lead author Axel H. Schönthal said, “The most immediate conclusion from our study is the strong advice that patients undergoing cancer therapy with Velcade must avoid green tea, and in particular all of its concentrated products that are freely available from health food stores.” Story in Science Daily, February 5, 2009.
- The percentage of futile (nontherapeutic) surgeries for liver tumors from colorectal cancer is decreasing, possibly due to the use of PET scanning before surgery. About half the time when surgeons were unable to complete surgery for liver metastases, tumors were discovered outside the liver during the operation. Analyzing over 500 surgeries to remove liver tumors, researchers found nontherapeutic resections 15 percent of the time between 1994 and 1997 and during 10 percent of surgeries between 1998 and 2001. By 2002 through 2005, the percentage of futile surgeries had fallen to less than 5 percent. Timothy M. Pawlik and colleagues, Annals of Surgical Oncology, February 2009.
- Lidocaine patches failed to reduce pain from surgical incisions that persisted after cancer-related surgery. Patients in the study were randomly assigned to apply patches with lidocaine or placebo during the day. After four weeks, groups were switched from lidocaine or placebo or vice versa. There was no difference in pain scores, although patients on the lidocaine treatment did report more general activity and ability to work. Andrea L. Cheville, Supportive Care in Cancer, online first January 14, 2009.
- A Food and Drug Administration combined panel of medical experts has recommended the withdrawal of pain medicines containing propoxyphene by a close vote of 14 to 12. Developed thirty years ago and better known by the brand names Darvon® and Darvocet®, the medicines are now manufactured and marketed as generic drugs. In 2007 more than 20 million prescriptions were written for them. The review was prompted by a petition from Public Citizen who presented testimony that the drugs had led to unnecessary deaths and provided only weak pain relief. They were withdrawn in the United Kingdom in 2005 when it was decided that risks outweighed benefits. Dow-Jones story from CNNMoney.Com, January 30, 2009.
- Plums may be the new superfruit. Cheaper than blueberries, they contain as many or more of the phytonutrients and antioxidants that prevent disease. Scientists at Texas A&M found that phytonutrients in plums inhibited the growth of breast cancer cells while not harming normal cells. And, while people may eat a few blueberries at a time, they will eat a whole plum and get the full benefit of its nutrition. Texas AgriLife Research reported in Science Daily, February 4, 2009.
- The FDA has cleared a new microwave ablation system developed by Covidien to treat liver tumors that cannot be surgically removed. The device uses microwaves to create intense heat within the tumor to destroy it. Now being used at the University of California at San Diego Medical Center, a thin antenna that emits microwaves can be inserted through the skin, laproscopically, or during an open surgery. UCSD News Release, February 3, 2009.