Several new studies reported at the conference show that tamoxifen's benefits can be maximized and its risks minimized by taking it for five years - the duration already favored by many cancer specialists.
The Swedish Breast Cancer Cooperative Group compared two years versus five years of tamoxifen treatment in 3,887 postmenopausal patients with early-stage breast cancers. After five years, the group that had been taking the drug for five years had fewer cancer recurrences than the two-year group. After 10 years, survival was 80 percent among the five-year group, compared with 74 percent among the two-year group.
A U.S. research effort, the National Surgical Breast and Bowel Project, compared five years versus 10 years of tamoxifen therapy for breast cancer patients with noncancerous lymph nodes. The study found no added benefit to taking the drug for more than five years, although it is too early to say whether the longer therapy is detrimental.
``It's our conclusion that five years should be the standard of care for . . . treatment after surgery,'' said Lars E. Rutqvist of the Swedish study group.
TREATING BREAST-DUCT LESIONS Debate continues to rage over the best way to treat precancerous lesions in breast ducts - or ductal carcinoma in situ (DCIS). Mammography has vastly increased detection of DCIS, which typically appears as tiny calcifications in the ducts.
Although highly curable, DCIS can recur and, in some cases, turn into invasive (spreading) cancer. Patterns of treatment vary widely, ranging from modified radical mastectomy - the disfiguring removal of the breast and some adjacent tissue - to excising just the lesion.
Many studies indicate that breast-conserving surgery is as safe as mastectomy, but there is disagreement over whether it should be followed by radiation, chemotherapy, or both.
Breast surgeon Gordon F. Schwartz of Thomas Jefferson University Hospital said he found that simply taking out the growth (excision), when followed by careful surveillance, is an effective alternative to more aggressive therapies. Of 194 breasts he treated that way, only 28 had recurrences during an average follow-up of 55 months. And only five of these, showed evidence of invasive cancer.
The findings contradict other studies which suggest that excision alone is not as safe as excision and radiation. Recently, the National Surgical Breast and Bowel Project found that radiation after excision reduced the rate of both noninvasive and invasive recurrences.
The debate may be resolved when researchers are better able to distinguish between different types of DCIS and treat them accordingly.
A MELANOMA VACCINE A vaccine against melanoma, a deadly form of skin cancer, is showing promise in testing at Thomas Jefferson University Hospital.
When the vaccine was given to 62 patients with melanoma that spread to the lymph nodes, 47 percent were free of cancer recurrence after four years and 58 percent were alive at four years. The survival rate for similar patients who are treated with surgery alone is 20 to 25 percent.
Patients older than 50 fared particularly well with the vaccine, according to David Berd, a Jefferson doctor who is heading the research. The vaccine is made from a patient's own tumor cells.
Similar vaccines are being developed for cancers of the lung, breast, colon, ovary, among others. Unlike traditional vaccines, they are not meant to prevent the disease, but rather to harness the body's immune system to fight off the cancer once it has occurred.
A HOT PAIN CREAM A cream made with the pungent ingredient in hot chili peppers can help ease the pain associated with surgical scarring.
When cream containing capsaicin was used for eight weeks by 99 patients experiencing persistent post-surgical pain, they reported more pain relief than when they used a cream without the same active ingredient.
The patients, who were recovering from a mastectomy or lung surgery, applied the cream around the incision site four times a day.
Charles Loprinzi, a cancer specialist at the Mayo Clinic who coordinated the study, said the capsaicin cream caused some skin irritation and bouts of coughing, presumably from the fumes given off, but that didn't stop the patients from using it.
For some patients, nagging scar pain can last for months and even years after surgery. Researchers surmised that an ingredient in hot chili peppers might be able to control the pain because people who eat a lot of peppers build up a tolerence to them and no longer feel the heat or pain.
Creams containing capsaicin are sold over-the-counter in drug stores for arthritis and muscle pain.