Chemotherapy Treatment of Cancer
Dr. Martin Shapiro’s article (Editorial Pages, Jan. 9), “Chemotherapy: Use Not Always Backed by Research,” has just come to our notice.
The article left readers with the mistaken impression that “many people with common malignancies are being treated with drugs not known to be effective.”
Dr. Shapiro’s view is understandable. Patients who complete chemotherapy successfully are less likely to attract public attention than patients who suffer side effects without benefit. However, the effectiveness of existing cancer treatments is very real, and much progress has been made based on basic and clinical research.
The fact is that half of the nearly 1 million Americans who will be diagnosed with cancer in 1987 are curable, and for the others there are increasingly hopeful treatment options. The history of this progress in cancer treatment has been steady.
During the 1950s, surgery and radiotherapy cured approximately 30% of cancer patients. Over the past 30 years, improvements in radiotherapy and the important discovery that drugs could actually cure advanced cancer have improved the curability rate to 50%.
Even greater effectiveness of treatment would be seen if the latest treatments were applied to all patients who could benefit. We believe there is also a well-intentioned lowering of dose by some physicians to reduce unpleasant, temporary side effects of chemotherapy. This lowering of dose intensity could also lower the patient’s chances of cure.
Unfortunately, not all cancer patients in the United States receive state-of-the-art cancer treatment, including drugs. It they did, survival rates would improve by 10% today, a saving of 30,000 additional lives each year.
In order to provide patients and doctors with the most current information about the best available treatments, the National Cancer Institute (NCI) has established Physicians Data Query (PDQ), a computer system that lists the most up-to-date treatments and clinical trials throughout the United States for more than 100 different cancers. This allows physicians to keep up with a rapidly advancing field and learn the latest in cancer treatment.
Dr. Shapiro acknowledges the success of the national cancer program in treating patients with lymphomas, leukemias, breast and testicular cancer. These are not rare cancers; the lymphomas occur more than 40,000 each year and more than 130,000 patients are diagnosed with the other diseases on this list. For example, only 10% of the patients with the most aggressive of these lymphomas were expected to survive five years in 1973. Today, 65% of these patients are curable. Similarly, the cure rate for testicular cancer, the most common cancer in men aged 18 to 30, has improved over the same period from 5% to 85%.
However, Dr. Shapiro also goes on to criticize the lack of effective treatments for the “most common” kinds of cancer such as cancer of the lung, colon and rectum. In fact, work in adjuvant chemotherapy (to prevent recurrence) represents one of the most promising areas of clinical cancer care.
“Adjuvant therapy” is the use of drugs, hormones or biological agents in combination with definitive surgery or radiation. The reason for the combined treatment approach is the fact that small deposits of cancer cells can escape from the primary tumor. Even complete removal of the tumor will not cure such a patient, since all sites of disease must be eradicated. Adjuvant therapy, already proven to be effective for many women with breast cancer, has been shown in recent studies to have positive effects in a number of patients with lung, colon and rectal cancers.
More than 65,000 patients each year are curable using existing adjuvant therapy and an additional 14,000 patients would be curable if promising adjuvant studies were generally applied in the community.
Dr. Shapiro finds fault with NCI reports of improved survival rates for Americans with cancer. NCI reports all cancer statistics--the good and the bad--and is just as interested in pointing out where survival improvements are are lagging.
For example, the figures indicate that black and minority Americans have a significantly poorer overall survival than whites with the same cancers. This information has prompted new programs to involve minority groups in both prevention and treatment studies of the NCI. On the other hand, real survival improvements cannot be denied, especially for all patients younger than 55 years, where five-year survival has climbed to 59%.
Research is paying off. However, when physicians develop an attitude that cancer is untreatable, the unfortunate fact is that they will not aggressively treat the cancer patient and the prophecy will be self-fulfilling.
Treatment for cancer patients will continue to improve because basic research is giving us a new understanding of the cancer cell and how to deal with it. Meantime, chemotherapy and other treatments are working--to cure, prolong life, and reduce the symptoms of thousands of patients with cancer.
GREGORY A. CURT MD
Deputy Director
Division of Cancer Treatment
National Cancer Institute
Bethesda, Md.
