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Showing papers on "Cancer published in 1982"


Book
01 Jan 1982
TL;DR: Part I: Molecular Biology of Cancer Molecular Methods in Oncology Section 1. Amplification Techniques Section 2. RNA Interference Section 3. cDNA arrays Section 4. Tissue arrays Section 5. Cytogenetics Section 6. Bioinformatics Genomics and Proteomics Molecular Targets in oncology.
Abstract: Part I: Molecular Biology of Cancer Molecular Methods in Oncology Section 1. Amplification Techniques Section 2. RNA Interference Section 3. cDNA arrays Section 4. Tissue arrays Section 5. Cytogenetics Section 6. Bioinformatics Genomics and Proteomics Molecular Targets in Oncology Section 1. Signal transduction systems Section 2. Cell cycle Section 3. Apoptosis Section 4. Telomerase Invasion and Metastases Angiogenesis Cancer Immunology Part II: Principles of Oncology Etiology of Cancer: Viruses Section 1. RNA Viruses Section 2. DNA Viruses Etiology of Cancer: Chemical Factors Etiology of Cancer: Tobacco Etiology of Cancer: Physical Factors Epidemiology of Cancer Section 1. Epidemiologic Methods Section 2. Cancer Statistics Principles of Surgical Oncology Section 1. General Issues Section 2. Laparascopic Surgery Principles of Radiation Oncology Principles of Medical Oncology Pharmacology of Cancer Chemotherapy Section 2. Pharmocokinetics Section 3. Pharmacogenomics Section 4. Alkylating Agents Section 5. Cisplatin and its Analogues Section 6. Antimetabolites Section 7. Topoisomerase Interactive Agents Section 8. Antimicrotubule Agents Section 9. Miscellaneous Chemotherapeutic Agents Pharmacology of Cancer Biotherapeutics Section 1. Interferon Section 2. Interleukin 2 Section 3. Histone deacetylase inhibitors as differentiation agents Section 4. Monoclonal Antibodies Pharmacology of Endocrine Manipulation Design and Analysis of Clinical Trials Part III: Practice of Oncology Cancer Prevention: Preventing Tobacco-Related Cancers Cancer Prevention: Diet and Chemopreventive Agents Section 1. Dietary fat Section 2. Dietary Fiber Section 3. Dietary fruits and vegetables: naturally occurring anticarcinogens Section 4. Retinoids, carotenoids and micronutrients Section 5. Dietary Carcinogens Section 6. Cyclo-oxygenase inhibitors Section 7. Physical Activity and Body Weight Cancer Prevention: Role of Surgery in Cancer Prevention Cancer Screening Advanced Molecular Diagnostics Advanced Imaging Methods Section 1. Functional and Metabolic Imaging Section 2. Interventional Radiology Cancer Diagnosis: Endoscopy Section 1. Gastrointestinal endoscopy Section 2. Respiratory Tract Cancer of the Head and Neck Section 1. Molecular Biology of Head and Neck Tumors Section 2. Treatment of Head and Neck Cancers Section 3. Rehabilitation after Treatment for Head Cancer of the Lung Section 1. Molecular Biology of Lung Cancer Section 2. Non-small Cell Lung Cancer Section 3. Small Cell Lung Cancer Neoplasms of the Mediastinum Cancers of the Gastrointestinal Tract

9,166 citations


Book
01 Feb 1982
TL;DR: This is an account of cancer epidemiology has been expanded and contains new material on cancer biology, molecular epidemiology, preventive strategies and specific types and sites of cancer.
Abstract: This is an account of cancer epidemiology. The second edition has been expanded and contains new material on cancer biology, molecular epidemiology, preventive strategies and specific types and sites of cancer.

2,881 citations


Journal ArticleDOI
TL;DR: Induction of mammary cancer in rats by administration of the chemical carcinogen 7, 12-dimethylbenz(a)anthracene reveals that the same factors influencing human breast cancer risk also affect the susceptibility of the rat mammary gland to the chemicalcar carcinogen.
Abstract: It has been demonstrated that in humans certain factors such as early menarche, late pregnancy, and nulliparity are associated with a higher risk of developing breast cancer, while early pregnancy acts as a protective factor. Induction of mammary cancer in rats by administration of the chemical carcinogen 7, 12-dimethylbenz(a)anthracene reveals that the same factors influencing human breast cancer risk also affect the susceptibility of the rat mammary gland to the chemical carcinogen. Nulliparous rats and rats undergoing pregnancy interruption are more susceptible to developing carcinomas. This fact has been attributed to the incomplete differentiation of the gland at the time of carcinogen administration. Parous rats are resistant to the carcinogenic effect of DMBA, which is explained by the complete development of the gland attained during pregnancy and lactation. This development is manifested by the differentiation of terminal end buds into secretory units, which have a smaller proliferative compartment; the epithelial cells of these secretory units have a longer cell cycle, less avidity for binding DMBA, and possess a more efficient DNA excision repair capacity.

618 citations


Journal Article
TL;DR: It is believed that the primary prevention of all these cancers will probably depend on modification of the factors which affect the secretion and metabolism of the responsible hormones rather than on control of exposure to classical exogenous initiators.
Abstract: Hormone-related cancers account for almost 30% of all cancer cases in the United States. Data from animal experiments and from epidemiological and endocrinological studies in humans support the hypothesis that the individual hormones which control normal growth of target organs can also create the proper conditions for neoplastic transformation. The concept that hormones can cause, i.e., increase the incidence of, human cancer is most developed for the four hormone-related cancers which are numerically the most important, namely, breast, prostate, endometrium, and ovary. Even for these sites, large gaps remain in our knowledge of the responsible hormones and the conditions which create the optimal opportunity for carcinogenesis. Although scanty, the available epidemiological evidence also suggests a hormonal role in the pathogenesis of testis cancer, thyroid cancer, and osteosarcoma. We believe that the primary prevention of all these cancers will probably depend on modification of the factors which affect the secretion and metabolism of the responsible hormones rather than on control of exposure to classical exogenous initiators.

600 citations


Journal ArticleDOI
01 Nov 1982-Cancer
TL;DR: Pain, when present, was often of at least moderate severity and was felt to interfere with patients' activity and enjoyment of life to a moderate to severe extent and was greater when the pain was caused by cancer than when it had another cause.
Abstract: The frequency, severity, and disruptiveness of pain related by 667 cancer patients are reported. The patients, all seen at a comprehensive cancer center, had cancers of the breast, colon and rectum, prostate, or various gynecologic sites. As expected, the proportion of patients with pain varied according to primary site and according to degree of progression of the disease. Pain, when present, was often of at least moderate severity and was felt to interfere with patients' activity and enjoyment of life to a moderate to severe extent. Degree of interference with activity and enjoyment of life was greater when the pain was caused by cancer than when it had another cause. Implications of these findings for professional and lay education and for treatment are discussed.

542 citations


Book
31 Oct 1982

522 citations


Journal Article

472 citations


Journal ArticleDOI
TL;DR: Seven of 16 patients showed objective evidence of tumor regression during the study, and clinical effects produced by IFLrA and IFN-C were similar, including fever, chills, myalgias, headache fatigue, and reversible leukopenia and granulocytopenia.
Abstract: Sixteen patients with advanced cancer were treated with recombinant-DNA-produced pure leukocyte A interferon (IFLrA) intramuscularly in doses ranging from 3 to 198 X 106units, with interva...

376 citations





Journal ArticleDOI
09 Apr 1982-JAMA
TL;DR: The data suggest that anal intercourse may be a risk factor for anal cancer in men, but not in women, having had syphilis and being single are associated with the practice of anal intercourse.
Abstract: To determine whether characteristics that are correlated with male homosexual behavior are associated with the incidence of cancer, the names of persons with a diagnosis of cancer in western Washington during 1974 to 1979 were linked to those in the state syphilis registry. Eight of 47 men with anal cancer were found to have had a reactive FTA test result; the expected number, based on the proportion of reactive cases among men with other sites of cancer, was only 0.40. Among men with anal cancer identified through ten population-based cancer-reporting systems in the United States, 24.4% had never been married, compared with 7.8% of men with colon and rectal cancer. Neither of these relationships was observed for women with anal cancer. Because in men, but not in women, having had syphilis and being single are associated with the practice of anal intercourse, our data suggest that anal intercourse may be a risk factor for anal cancer. ( JAMA 1982;247:1988-1990)

Journal ArticleDOI
TL;DR: In this article, the authors extend an earlier study by 4 years, 1975-1978, and find leukemia as a cause of death among survivors has continued to decrease and now differs from the control group only in Hiroshima.
Abstract: The present study extends an earlier one by 4 years, 1975-1978. We find leukemia as a cause of death among survivors has continued to decrease and now differs from the control group only in Hiroshima. For cancer other than leukemia the increase in absolute risk has become more marked as the cohort has aged and especially so in Nagasaki where it is now statistically significant for the first time. In addition to previously demonstrated sites, i.e., lung, breast, stomach, esophagus, and urinary tract, colon cancers and multiple myeloma can now be shown to be related to exposure. No significant relationship to radiation can as yet be established for malignant lymphoma, rectum, pancreas, and uterine cancer. The time from exposure to death is shortened for leukemia depending on dose but not for other cancers, and radiation-induced cancers other than leukemia seem to develop proportionally to the natural cancer rate for the attained age. For specific age-at-death intervals, both relative and absolute risks tend...

Journal ArticleDOI
TL;DR: Data suggest that total thyroidectomy is the treatment of choice for patients with thyroid cancer because residual cancer would persist in the remaining thyroid tissue in at least 61% of patients if only lobectomy had been performed.
Abstract: There is considerable controversy about the most appropriate treatment of patients with thyroid cancer. This report concerns the author's experience with 82 consecutive patients having total thyroidectomy from January 1977 through December 1981. The age of the patients ranged from 21 to 86 years (mean age 44 years). There were 44 women and 38 men. Twenty-four patients (29%) had had previous thyroid operations; ten patients (11%) had coexistent parathyroid adenomas removed; and seven patients (8.5%) had modified radical neck dissections. Thirty-four patients (41%) had a history of radiation to the head and neck, and 12 (35%) of the 34 irradiated patients and 51 (63%) of the entire group of 82 patients had thyroid cancer (45 papillary, five follicular, one medullary). Coexistent lesions in the patients with papillary cancer included Hashimoto's thyroiditis, five patients; parathyroid adenomas, four patients; Graves' disease, one patient; Hurthle cell neoplasm, one patient; and amyloid struma, one patient. If less than total thyroidectomy had been performed, 26 (51%) of the 51 patients with thyroid cancer would have had cancer left in the residual thyroid lobe, and focal cancers in the lobe opposite to the one containing the nodule for which the operation was performed would have been missed in five patients (10%). Five of the 20 patients with unilateral cancer had follicular cancer. Complications included one case of permanent hypoparathyroidism and two cases of transient bilateral recurrent laryngeal nerve palsy. Ninety-six per cent of the patients were discharged within four days of thyroidectomy, 94% by three days, and 79% by two days. Uptake of radioactive iodine was not above background levels in nine (26%) of the 35 patients studied after operation and was less than 1% in the remainder. These data suggest that total thyroidectomy is the treatment of choice for patients with thyroid cancer because residual cancer would persist in the remaining thyroid tissue in at least 61% of patients if only lobectomy had been performed. Total thyroidectomy can be done with minimal permanent disability in patients with benign and malignant thyroid tumors, in patients who have had previous thyroid operations, and in patients with coexistent hyperparathyroidism.

Journal ArticleDOI
21 Jan 1982-Nature


Journal Article
TL;DR: No relationship was observed between AHH/cytochrome c activity and age of patient, numbers of cigarettes smoked, family history of cancer, location or histological type of tumor, or level of phytohemagglutinin blastogenesis; whether the higher AHH levels are the cause or the result of the primary lung cancer remains to be determined.
Abstract: Blood samples from closely monitored patients at the Veterans Administration Hospital in Houston, Texas, were collected, coded, and sent to Microbiological Associates over an 8-month period. Lymphocytes were isolated and cryopreserved at -190 degrees. Lymphocyte samples were simultaneously thawed, phytohemagglutinin activated, and analyzed for benz(a)anthracene-induced aryl hydrocarbon hydroxylase (AHH) levels, [3H]thymidine incorporation, and reduced nicotinamide adenine dinucleotide-dependent cytochrome b5 (cytochrome c) reductase activity. Determinations were made at both 96 and 120 hr in culture, and peak activities were compared among a total of 51 individuals who expressed such lesions as squamous cell carcinomas (22%), adenocarcinomas (14%), oat cell carcinomas (6%), chronic obstructive pulmonary disease (22%), and other nonmalignant diseases. Of the 14 highest AHH/cytochrome c activities observed, all were found in patients with primary lung cancer. Mean AHH/cytochrome c activities were 0.89 for lung cancer patients (a total of 21) and 0.47 for noncancer patients (a total of 30) (p less than 0.001). No relationship was observed between AHH/cytochrome c activity and age of patient, numbers of cigarettes smoked, family history of cancer, location or histological type of tumor, or level of phytohemagglutinin blastogenesis ([3H]thymidine cpm/cytochrome c). Whether the higher AHH levels are the cause or the result of the primary lung cancer remains to be determined.


Journal Article
TL;DR: It is clear from the past two decades of research in cancer immunology that a far more detailed knowledge of surface antigens of tumor cells will be necessary before the possibility of immunological control of cancer is assessed.
Abstract: The major focus of cancer immunology has shifted away from arguments about the validity of the immunosurveillance theory of cancer to the more basic question of tumor-specific antigens Despite vast effort aimed at demonstrations of such antigens, their existence in the generality of cancer remains unproved Serological analysis of 3 tumor types, mouse leukemia and sarcoma and human malignant melanoma, has received the most attention, and a rudimentary classification of the surface antigens expressed by these tumors has begun to emerge The prime candidates for antigens that can be considered tumor specific are the few instances of Class 1 antigens that have now been serologically defined on mouse and human tumors These antigens show an absolute restriction to individual tumors and are not demonstrable on any other normal or malignant cell type Biochemical and genetic characterizations of Class 1 antigens represent an essential next step in an evaluation of the significance of these antigens The surprising features of the thymus leukemia (TL) antigens of the mouse provide insight into the genetic origin of another key class of tumor antigens, ie, those with characteristic properties of both differentiation and tumor-specific antigens In normal mice, TL antigens are restricted to cells in the thymus, and strains differ with regard to expression versus nonexpression of TL antigens Genetic information for TL is universal in mice, however, as leukemias that develop in mice normally lacking TL are found to express TL What is clear from the past two decades of research in cancer immunology is that a far more detailed knowledge of surface antigens of tumor cells will be necessary before we can begin to assess the possibility of immunological control of cancer

Journal ArticleDOI
TL;DR: Subsequent cancer incidence was determined in the population-based incidence cohort of Rochester, Minnesota, residents diagnosed with diabetes mellitus between 1945 and 1969 and the potential biases of increased medical surveillance among diabetics and exacerbation of subclinical diabetes by occult malignancy did not appear to be important.

Journal ArticleDOI
21 May 1982-JAMA
TL;DR: Risk of cancer was studied prospectively in four families described in 1969 as having diverse neoplasms, especially breast cancer and soft-tissue sarcoma, and in ten of 31 surviving family members, there developed 16 additional cancers between 1969 and 1981.
Abstract: Risk of cancer was studied prospectively in four families described in 1969 as having diverse neoplasms, especially breast cancer and soft-tissue sarcoma. Between 1969 and 1981, in ten of 31 surviving family members, there developed 16 additional cancers (expected, 0.5). There were five breast carcinomas, four soft-tissue sarcomas, and seven other cancers. In eight patients, multiple primary cancers developed, including three softtissue sarcomas and one mesothelioma at sites of prior radiotherapy. (JAMA1982;247:2692-2694)

Journal ArticleDOI
TL;DR: Data from the 1980 long- and short-term surveys of the American College of Surgeons Commission on Cancer were examined to identify recent trends in the management of prostate cancer and suggest changing patterns of care for prostatic cancer in the patients observed from 1974 to 1979.


Journal ArticleDOI
01 Jul 1982-Cancer
TL;DR: The excellent survival of patients with simultaneous ovarian and uterine endometrioid carcinomas is better than would be expected for either Stage III adenocarcinoma of the endometrium or Stage II ovarian carcinoma.
Abstract: Twenty-nine patients had simultaneous malignant epithelial neoplasms of the uterine corpus and ovary. Three groups were defined on the basis of tumor histology: Group A: those with endometrioid carcinoma in both the uterus and ovary; Group B: those with special variants of corpus carcinoma (papillary, clear cell, mucinous) and identical neoplasms in the ovary; and Group C: those whose uterine and ovarian carcinomas were of dissimilar histologic types. Sixteen women had endometrioid carcinoma in both sites. The median age at diagnosis, 41 years, was younger than is usual for corpus or ovarian cancer. For all 16 patients, the grade of the ovarian endometrioid carcinoma was similar to that of the endometrioid carcinoma of the uterine corpus. Seven patients had bilateral ovarian neoplasms. Only one patient had myometrial invasion by the corpus carcinoma. No patient with simultaneous ovarian and uterine endometrioid carcinoma, regardless of grade, has died of cancer although one vaginal relapse was treated successfully. This excellent survival of patients with simultaneous endometrioid carcinomas is better than would be expected for either Stage III adenocarcinoma of the endometrium or Stage II ovarian carcinoma. These simultaneously occurring endometrioid neoplasms of ovary and endometrium are considered to be separate primary tumors. The morphologic reasons for this view and therapeutic implications are discussed. In contrast to the patients with endometrioid carcinoma, the eleven patients with other histologic types of carcinoma in the ovary and corpus were older (median age, 61 years) and more often post-menopausal (90%). These neoplasms were more aggressive, with frequent deep myometrial involvement (63%), tubal involvement (27%), and extension to other pelvic tissues (36%) at the time of initial diagnosis. Six of these 11 patients succumbed to their cancer despite surgical therapy and radiation. The distribution of tumor in some of these patients with nonendometrioid types of carcinoma is suggestive of a single primary with metastases. The therapeutic implications of these findings are discussed. Cancer 50:163–170, 1982.

Journal ArticleDOI
TL;DR: The National Cancer Institute estimates that 51,000 new cases of head and neck cancer will occur in 1982 and will result in 16,000 deaths, which will include 26,600 cancers of the buccal cavi...
Abstract: THE National Cancer Institute estimates that 51,000 new cases of head and neck cancer will occur in 1982 and will result in 16,000 deaths. These cases will include 26,600 cancers of the buccal cavi...

Journal Article
TL;DR: UCA is a basic cancer and DCA is a variable cancer of the stomach, which are different in biological behaviors, such as growth pattern, invasiveness, metastasis, and prognosis.
Abstract: Historical review of the pathological investigation on stomach cancer in Japan shows that the central problem had been whether or not gastric cancer developed from chronic peptic ulcer. This theory of ulcer cancer sequence was developed from chronic peptic ulcer. This theory of ulcer cancer sequence was supported by many researchers after the war in the period of 1946-64. Subsequently, systematic studies made at the Cancer Institute revealed that carcinoma arises from the gastric mucosa independently of chronic ulcer. The pathological interest then shifted toward investigation of the histogenesis and biological characteristics of gastric carcinoma. It is concluded that gastric carcinoma can be classified into two types; undifferentiated carcinoma (UCA or gastric type) and differentiated one (DCA or intestinal type). The former arises from the ordinary mucosa and cancer phenotype of this carcinoma resembles to that of the ordinary mucosa, and the latter arises from the metaplastic epithelium of intestinal type showing a cancer phenotype resembling to that of the intestinal metaplastic epithelium. These two carcinomas are also different in biological behaviors, such as growth pattern, invasiveness, metastasis, and prognosis. The frequency of UCA is almost the same in both sexes. DCA, however, occurs more often in male than in female. The time trend data indicates that in both sexes the number of DCA decreased, but that of UCA is steady, so that the ratio of DCA to UCA decreased since 1965. These results combined with the concept of the basic and variable cancer leads to a conclusion that UCA is a basic cancer and DCA is a variable cancer of the stomach.

Journal ArticleDOI
01 Jan 1982-Cancer
TL;DR: This conservative approach offers most women with operable breast cancer an excellent chance at breast preservation with the same chance for ten‐year survival as with radical mastectomy.
Abstract: Since 1960 more than 3000 consecutive patients with operable infiltrating breast carcinoma were treated by radiation therapy with or without primary limited surgery, which usually consisted of local excision. For tumors smaller than or equal to 5 cm the ten-year crude survival rate is 77% for patients without palpable axillary nodes (T/sub 1-2/N/sub 0/) and 63% for patients having axillary adenopathy (T/sub 1-2/N/sub 1/). For operable tumors exceeding 5 cm in diameter (T/sub 3/N/sub 0-1/) the ten-year crude survival is 34%. Thirty-five percent of the patients alive free of disease at ten years required a secondary operation for presumed local or regional tumor persistence or recurrence, although no residual disease was found in 24% of the operative specimens. Local-regional recurrence had no adverse effect on ten-year survival. This conservative approach offers most women with operable breast cancer an excellent chance at breast preservation with the same chance for ten-year survival as with radical mastectomy.

Journal Article
TL;DR: A rapid method for the measurement of serum and/or plasma, lipid-associated sialic acid levels has been developed and compares favorably with the most widely used tumor marker test, that for carcinoembryonic antigen.
Abstract: A rapid method for the measurement of serum and/or plasma, lipid-associated sialic acid levels has been developed. This test has been applied to 850 human sera of which 670 came from patients with nine categories of malignant disease, 80 from persons with benign disorders, and 100 from normal individuals. Lipid-associated sialic acid concentrations were found to be significantly increased (p less than 0.001) in all groups of cancer patients as compared to both those with benign diseases and normal controls. Test sensitivity in the detection of cancer ranged from 77 to 97%. Specificity was, respectively, 81 and 93% for the benign and normal groups. In small samples of patients, no association between test values and tumor burden was found. This test compares favorably with the most widely used tumor marker test, that for carcinoembryonic antigen.

Journal ArticleDOI
15 Mar 1982-Cancer
TL;DR: Differences in survival after five years with respect to both site of cancer in the colon and stage of initial disease are shown, indicating that many left‐sided large bowel cancers have a slowly progressive natural history.
Abstract: For 1704 patients with large bowel cancer compiled by the Armed Forces Central Medical Registry, selected prognostic factors were related to five-year or longer survival. The majority of late deaths (those occurring after five years) resulted from cancer in the descending colon, sigmoid colon or rectum rather than from cancer in the right or transverse colon. For example, among all patients with cancer of the rectum, 15.4% of those with Dukes' B tumors and 10.9% of those with Dukes' C tumors died of rectal cancer between five and ten years after diagnosis. When late survival rates were compared, patients with right and transverse colon cancer (8 deaths/93 at risk) fared significantly better than those with left colon and rectal cancer (33 deaths/171 at risk; P = 0.01). Among patients with left-sided colon and rectal carcinoma, a further significant difference in late survival was found when stage of disease was considered: patients with Dukes' A cancers (3 deaths/47 at risk after five years) fared better than those with Dukes' C cancers (21 deaths/74 at risk) (P = 0.002). For Dukes' B and C stages of disease, patients with left colon and rectal cancer fared worse than those with right and transverse colon lesions after 60 months. Of all patients who died of large bowel cancer after five years, 69% had a recurrence of cancer by 60 months, and most late recurrences were located in the descending and sigmoid colon and in the rectum. These results show differences in survival after five years with respect to both site of cancer in the colon and stage of initial disease. Our findings indicate that many left-sided large bowel cancers have a slowly progressive natural history.

Journal ArticleDOI
TL;DR: It is suggested that future therapeutic trials, using survival as a measure of response of patients with liver metastases from colorectal cancer, must be prospectively controlled before selection factors can be differentiated from significant therapy effect.
Abstract: The median survival of all patients with hepatic metastases from colorectal cancer referred to the Sidney Farber Cancer Institute during a five-year period was 12.5 months. Two major factors influenced survival. The first was extent of disease at presentation. The second was the histologic grade of the cancer. The median survival of patients presenting with the least disease, characterized by less than four liver nodules visible on liver scan (n=38), normal liver size on physical examination (n=60), normal liver function test results (n=30), and normal performance status (n=91), was between 18 and 24 months, regardless of treatment. The median survival of those few patients (n=13) who had objective responses to a variety of treatments, most of whom also had minimal disease at presentation, was also 24 months. Patients whose tumors were poorly differentiated or who had abnormal performance status or weight loss of greater than 10 per cent at presentation survived only six months (median). Those with four or more liver nodules, hepatomegaly (greater than 16-cm vertical span on physical examination), or abnormal liver function test results, survived ten, eight, and 12 months (median), respectively. It is concluded that a significant group of patients survived longer than would have been predicted by earlier literature surveys after the diagnosis of colorectal cancer metastatic to the liver. It is suggested that future therapeutic trials, using survival as a measure of response of patients with liver metastases from colorectal cancer, must be prospectively controlled before selection factors can be differentiated from significant therapy effect.