In the June 16 issue of The Times, Dr. Lawrence Power discussed several important issues with respect to the current status of cancer treatment (Food and Fitness/Diet Therapy and Cancer Treatment). While I am in agreement with Dr. Power on the potential role of diet in cancer prevention, I wish to offer a different perspective with respect to the current status of cancer chemotherapy.
Unlike many illnesses, cancer is the only major disease where drugs can be given with curative intent. Heart disease, diabetes, hypertension and even arthritis are examples of major illnesses where drugs offer no curative potential. Thirty years ago, advanced cancer was uniformly fatal. Today, impressive cure rates are seen in an increasing number of cancers for which surgery alone is not curative (testicular cancer 90%, childhood rhabdomyosarcoma 95%, choriocarcinoma 90%, Hodgkin's disease 60%). These improvements are due to advances in cancer chemotherapy and radiotherapy. The diseases listed above are most commonly seen in the young, and because of this, the number of productive years saved is underestimated by a simple look at the decrease in mortality rates.
Substantial progress is being made in diseases that affect older Americans as well. Large cell lymphoma is now curable in 65% of cases, ovarian cancer can be cured in 20% of patients, and cures have been demonstrated in acute myelocytic leukemia and small cell lung cancer--all of these due to chemotherapy.
Recent data analyses have shown that literally thousands of women (young and old) have clearly benefited from so-called adjuvant chemotherapy for breast cancer, and there are many other diseases where the same type of chemotherapy has shown clear impact on patient survival, including cancers of the head and neck, and soft tissue sarcomas.
The role of adjuvant treatment in breast cancer is the topic for discussion at the September meeting in Bethesda, Md., referred to in Power's column. This meeting will not attempt "to evaluate and separate all treatment procedures" for cancer as suggested by Power; to do so would be impossible in a single meeting. Contrary to Power's statement, there is general agreement in the medical community on the appropriate therapy for the curable malignancies, and at least 50% of patients diagnosed as having cancer in 1985 will be cured with surgery, radiotherapy, and chemotherapy. This cure rate has been advancing steadily over the past two decades.
In an effort to increase the pace of progress in cancer treatment, studies are currently under way to determine the manner in which tumor cells become resistant to drugs and how that resistance may be overcome. Also, new agents of great promise are being tested for use in those cancers resistant to currently used agents.
I agree with Dr. Power that there is a major role to be played by diet in cancer prevention, and the NCI strongly supports research in that area. However, the current and future prospects of chemotherapy and new biologic agents in cancer treatment are substantially brighter than the picture Dr. Power painted.
EDDIE REED, MD
Special assistant to the director
Division of Cancer Treatment
National Cancer Institute