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The National Recombinant DNA Advisory Committee (RAC) and its
Gene Therapy Subcommittee
Each of these review groups contains scientists, clinicians, ethicists and lay people.
Finally, before any attempts at gene therapy can begin, final approval must be received from the Director of the National Institutes of Health.
This review process is very detailed in order to provide careful consideration not only to the importance of the science but also to issues of patient safety.
NON-CONVENTIONAL CANCER TREATMENTS
Question. Dr. Broder, I want to thank you for visiting with Congressman Berkly Bedel and discussing with him non-conventional treatments. How can the Congress be sure that we are giving adequate attention to non-conventional treatments, some of which turn out to become mainstream? For example, I understand radiation therapy was regarded as radical and not recommended for many years, but now it is common practice.
Answer. As noted in the Office of Technology Assessment's (OTA) report on Unconventional Cancer Treatments, one of the greatest impediments to the evaluation of these approaches is the lack of interpretable scientific data. To address this, the NCI has placed responsibility for the evaluation of Unconventional Cancer Treatments (UCTS) in the Investigational Drug Branch of the Cancer Therapy Evaluation Program which is also responsible for the early clinical development of "conventional" approaches (e.g., chemotherapy and biological response modifiers) for the treatment of cancer. The Chief of this Branch, Dr. Michael J. Hawkins, recently attended the Fourth Annual Lloyd Symington Foundation Conference on New Directions in Cancer Care at the request of Dr. Michael Lerner, à Special Consultant to the OTA for their report on UCTS. At this meeting, Dr. Hawkins discussed the type of clinical data that would be viewed as scientifically meaningful and proposed some approaches which could be used to generate such data. These data, if positive, would warrant the conduct of confirmatory trials by the NCI and/or could be cited in investigator-initiated grant applications. As a result of this meeting and Dr. Hawkins' presentations, discussions on how to best generate such pilot data have begun with proponents of psychospiritual and dietary approaches to the treatment of cancer. ; While remaining open to novel or unconventional ideas, it is important to stress that the NCI must adhere to sound scientific methods. Moreover, NCI must provide a level playing field to ensure that all individuals who make claims for new cancer cures are held to the same standards of proof.
In response to one of the Options proposed in the OTA report, the NCI is in the process of developing guidelines for the preparation of "best case series." We anticipate that this document will be available not later than May, 1991. However,
there are significant practical problems and scientific limitations associated with the preparation and interpretation of these retrospective analyses. The NCI feels it is far preferable to generate new data in small pilot studies and will provide guidelines for the conduct of such studies in this document as well. These studies typically require fewer than 100 patients. For most of the UCTS, uninterpretable data have already been collected on many more patients who have, unfortunately, received the UCTs in an uncontrolled fashion. This pilot study approach has been used in the past with success to identify both promising and ineffective UCTS. Based on a small (65 patient) randomized pilot study which demonstrated increased survival in patients receiving hydrazine sulfate, the NCI initiated three large scale e confirmatory, clinical trials in the Cooperative Groups. In contrast, similar studies of Laetrile and Vitamin C were negative. It is worth stressing that the NCI is actively studying Vitamin C as a possible chemoprevention agents in various settings.
CANCER INCIDENCE RATES
Question. Dr. Broder, I have a chart that was included in the Cancer By-Pass budget that shows the incidence rates for the 24 major types of cancer. Fifteen of these cancers are showing increasing incidence rates between the period 1973 to 1987. Are we making progress in the war on cancer?
Answer. Yes, there are indications that improvements in cancer rates have occurred, we have good news and bad news in our statistics.
Let me begin first with the good news. In persons under 65 we show a continuing decline in cancer mortality, a total of 4.3 percent from 1973 to 1988. We believe the decline is due to two broad factors. First, we cite the effects of cancer prevention and early detection regimens, specifically, reduction in smoking, an increase in early detection of breast cancer among younger women, an increase in the percentage of women undergoing cervical cancer screening, and, perhaps, the impact of a changing diet. Secondly, we believe there has been a general improvement in treatment and early detection and that these advances have been applied to a fuller extent in the younger population group.
Many cancers show startling reductions in mortality for persons under age 65. For example, as shown in Table 1, childhood cancers have declined 36 percent, Hodgkin's disease declined 54 percent, bladder cancer 32 percent, colorectal cancer 16 percent, stomach cancer down 30 percent, breast cancer in women under 50 declined 11 percent, and oral cancer fell by 21 percent. We even see a change in pancreatic cancer, one of the deadliest of all cancers which for all persons under 65, has fallen 13 percent. As a direct result of changes in smoking habits, the net change in lung cancer mortality among men since 1973 has been an increase of only one-half of one percent over the entire period. The figure for females is a startling 67 percent (with a corresponding figure for those over age 65 of 166 percent.)
Other increases for persons under age 65 include melanoma up 16 percent, breast cancer in women over 50 increased 4.8 percent,
esophageal cancer increased by 5 percent, multiple myeloma up 11. percent.
In persons over 65 the net change in mortality for all cancers combined is an increase of 12.9 percent over the period 1973 to 1988. Reviewing the figures in Table 2, we can see that fewer cancers show decreases for persons over 65. Some of the cancer showing decreases for persons 65 and over include: oral cancer down 15 percent, stomach down 33 percent, colorectal cancers down nine percent, cervical cancer down 42 percent, and Hodgkin's disease down 51 percent.
Cancers showing increases for persons 65 and above include: non-Hodgkin's lymphoma up 41 percent, brain cancer up 59 percent, melanoma also up 59 percent, and lung cancer for males and females combined up 55 percent. As I noted lung cancer among females 65 and over is up 166 percent while the figure for males is 32 percent, reflecting the decrease in smoking among males, the smaller decrease among females and the fact that females began to smoke somewhat later than their male counterparts.
The challenge posed by these age-specific statistics is obvious: the clear and unequivocal progress seen among persons under 65 must be extended to a greater extent to those over 65. Some of the increases among older Americans are well understood, while others are baffling. For example, the increase in melanoma is strongly believed to be due to increased ultraviolet radiation, in particular, sun exposure. The increase in breast cancer mortality, particularly in the face of improved treatment, may be due to changes in diet. Changes in other risk factors have been suggested but at this point in time do not correlate with the mortality increase. The increase in brain cancer is most likely due to improved methods of identifying causes of death. In other . words the true rate of death from brain cancer has not changed, but the frequency at which we diagnose the cause of death correctly has improved because of new technology such as the CAT scan, and improved access to health care through Medicare. Another baffling change is in non-Hodgkin's lymphoma with an increase of 41 percent among persons over age 65. An increase of two percent is due primarily to AIDS which makes its victims more susceptible to non-Hodgkin's lymphoma and to Kaposi's sarcoma.
Blacks bear a disproportionate burden of cancer, a burden marked by increasing mortality rates for many cancer sites in sharp contrast to more favorable trends among whites. The mortality rate among blacks is 213.0 deaths per 100,000 persons in contrast to 168.5 among whites. The sex-specific rates show that black males have a mortality rate of 293.4, 38 percent higher than the rate of 213.1 for white males. The figures for females are 158.5 deaths per 100,000 persons for black females, a figure that is 14 percent higher than the rate of 139.0 deaths per 100,000 for white females. The trend figures show an increase in mortality for whites of 5.3 percent from 1973 to 1988 while the corresponding figure for blacks is 9.6 percent.. In other words, not only are the mortality rates higher among blacks, the rate of change is greater among blacks. In a sense the cancer mortality, gap between blacks and whites has widened.
NCI has recognized this disparity and has instituted an extensive program of initiatives, touching on all aspects of cancer to address this problem from epidemiology and surveillance studies to identify the differences, to basic research on understanding the differences, to treatment studies, to cancer prevention and control and outreach activities. NCI is committed to reducing the differential in experience as it works to reduce the overall levels of morbidity and mortality from cancer.
Turning to women's health, breast cancer is the most frequent cancer among women, responsible for 175,000 new cancers each year and 44,500 deaths. The next four cancers among females (ranked according to incidence) are colorectal cancer (78,500 cases, 30,500 deaths), lung cancer (60,000 cases, and the leading cause of cancer deaths with 51,000 deaths per year), uterine cancer (33,000 cases, 5,500 deaths), and ovarian cancer (at 20,700 cases and 12,500 deaths annually). Cervical cancer accounts for 13,000 cases and 4,500 deaths annually and ranks tenth among all cancers detected in women. Together, breast, uterine, cervical and . ovarian cancers account for 44 percent of the 555,000 cases recorded annually among women. Progress among these cancers has been impressive, particularly among younger women as shown in the following table:
Women under 50 show decreases in each of these major cancers specific to females. Although breast cancer does occur among males less than one-half of one percent of all breast cancer occurs among males.)
all these figures show that, yes, we are making progress against cancer, but we also face great challenges. As the population ages and increases the burden of cancer may well increase because the highest rates of cancer are among the elderly. These figures show that we have made progress and we expect this progress portends the advances we will see as today's younger population ages and as more prevention, diagnostic, and treatment advances reach the point where technology transfer is feasible.
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