Cellular differentiation of the immune system of mice. II. Frequency of unipotent splenic antigen-sensitive units after immunization with sheep erythrocytes.

Spleen cell suspensions of primed donor mice containing precursors of immunocytes have been transplanted into X-irradiated recipient mice 122-138 days after immunization. Following secondary stimulation with antigen (sheep erythrocytes), these precursors, called antigen-sensitive units (ASU), gave rise to progeny cells secreting specific antibody in the spleens of recipients. Single cells releasing IgM hemolysins (direct plaque-forming cells or PFC), IgG hemolysins (indirect PFC), and hemagglutinins (cluster-forming cells or CFC) were enumerated. By transplanting graded and limiting numbers of primed spleen cells, inocula were found which contained one or a few ASU reaching the recipient spleens. We estimated, thereby, the frequency of ASU detectable by our procedures in donor cell suspensions. The values obtained from direct and in-indirect plaque assays, and from cluster assays were 1 in approximately 8.0 x 10(5), 1 in approximately 4.4 x 10(5), and 1 in approximately 5.9 x 10(5) nucleated spleen cells, respectively. The number of splenic ASU for direct PFC was not greater than that of unimmunized mice; however, immunization greatly increased the number of splenic ASU for indirect PFC and for CFC. By applying to each recipient spleen direct and indirect plaque tests and cluster tests, we found that positivity for each type of immunocyte was independent from that of the other two types. These results confirm the unipotent nature of splenic ASU in general, and document the commitment of ASU primed with SRBC to generate progeny cells secreting antibody of a single molecular (IgM or IgG) or functional (lysin or agglutinin) class. We concluded that splenic ASU are composed of relatively differentiated cells of the immune system of mice. With respect to specificity and class differentiation, ASU appear to be as specialized as antibody-producing cells themselves. Our results did not support the view that ASU-derived clonal populations shift from IgM to IgG antibody production.

Cellular differentiation of the immune system of mice. IV. Lack of class differentiation in thymic antigen-reactive cells.

Thymocytes and marrow cells of unprimed donor mice were mixed in vitro and transplanted into X-irradiated syngeneic mice. 18 hr later, sheep erythrocytes were injected to induce immune responses. Splenic plaque-forming cells (PFC) secreting IgM (direct PFC) or IgG (indirect PFC) hemolytic antibody were enumerated at the time of peak responses. By transplanting graded and limiting numbers of thymocytes with 4 x 10(7) marrow cells, inocula were found which contained one or a few thymic antigen-reactive cells (ARC) reaching the recipient spleens, interacting with marrow cells, and inducing PFC formation. The frequency values of ARC inferred from direct and indirect plaque assays were very similar, 1 in approximately 10(7) thymocytes. Furthermore, statistical analysis indicated that the formation of direct PFC was not independent of the formation of indirect PFC. This was interpreted to mean that ARC were not specialized themselves and did not determine the molecular class of antibody to be secreted after interaction with marrow cells. Spleens of thymus-marrow grafted mice containing one or two ARC and non-limiting numbers of marrow precursors of PFC (P-PFC), had direct and indirect PFC clustered in several focal areas. Assuming that each focal area represented the progeny of one P-PFC that had interacted with ARC, these results confirmed the statistical evidence for lack of class differentiation in thymic ARC, and also indicated that each ARC or its progeny cells interacted with more than one P-PFC of either class.

Cellular differentiation of the immune system of mice. V. Class differentiation in marrow precursors of plaque-forming cells.

Marrow cells and thymocytes of unprimed donor mice were mixed in vitro and transplanted into X-irradiated syngeneic hosts. 18 hr later sheep erythrocytes were injected to induce immune responses. Splenic plaque-forming cells (PFC) secreting IgM (direct PFC) or IgG (indirect PFC) hemolytic antibody were enumerated at the time of peak responses. By transplanting graded and limiting numbers of marrow cells with 5 x 10(7) thymocytes, inocula were found that contained few precursors of PFC (P-PFC) reaching the recipient spleens, interacting with thymocytes, and generating PFC. However, the frequency of responses in relation to the number of grafted marrow cells did not follow Poisson statistics, presumably because the interaction of marrow cells with thymocytes was more complex than a single or a one-to-one cell event. The frequency of direct PFC responses was greater than that of indirect PFC responses in 13 of 15 groups of mice tested. This was interpreted as evidence for the existence of two classes of P-PFC, each of which was restricted to generate either direct or indirect PFC. The precursors of direct PFC were approximately 15 times more frequent than those of indirect PFC. Since thymic antigen-reactive cells were not differentiated for antibody class, it follows that antigen-sensitive units reactive to sheep erythrocytes owe their class restriction to specialized marrow cells. Specialization of P-PFC may have arisen within marrow cell lines by differentiation, or may have been conferred upon P-PFC by interaction with other cells, including those of the irradiated host.

Cellular differentiation of the immune system of mice. I. Separate splenic antigen-sensitive units for different types of anti-sheep antibody-forming cells.

Spleen cell suspensions of unprimed donor mice containing precursors of immunocytes have been transplanted into X-irradiated recipient mice. In the presence of antigen (sheep erythrocytes) these precursors, called antigen-sensitive units, gave rise to progeny cells secreting specific antibody. We studied quantitatively the production of cells releasing IgM hemolysins (direct plaque-forming cells), IgG hemolysins (indirect plaque-forming cells), and hemagglutinins (cluster-forming cells). We found that each of these immunocyte populations was distinct, i.e., that cells releasing agglutinins did not, as a rule, release hemolysins, and vice versa. We also found that cell populations secreting IgM hemolysins did not shift, under certain experimental conditions, to the production of IgG hemolysins during the primary immune response. By transplanting graded numbers of spleen cells, we succeeded in limiting to one or a few the number of antigen-sensitive units that reached the recipient spleen. We estimated thereby the frequency of antigen-sensitive units in donor cell suspensions and tested their potential for production of immunocytes of more than one type. Our results indicated that antigen-sensitive units were unipotent for they displayed in the spleens of unprimed donors the same restrictions of function and heterogeneity (antibody-specificity differentiation, antibody-class differentiation) found among antibody-forming cells. Furthermore, antigen-sensitive precursors for direct plaque-forming cells, indirect plaque-forming cells, and cluster-forming cells were detected in the spleens of unprimed mice in different frequencies, i.e., 1 in approximately 10(6), 1 in approximately 7 x 10(6), and 1 in approximately 19 x 10(6) spleen cells, respectively. We concluded that relatively advanced differentiation of potentially competent cells occurs before sheep erythrocyte administration. The relevance of this finding for the broad spectrum of immunologic reactivities and for the heterogeneity of antibody responses to given antigens was discussed.

U.S. centralized cancer patient data system for uniform communication among cancer centers.

The evolution of the Centralized Cancer Patient Data System, a cooperative venture of the 21 comprehensive cancer centers in the United States, and its structure at the end of 3 years of data collection are described. Functions of the data system are detailed in terms of input and output. It is concluded that the short-run objective of establishing a data system to provide high-quality patient data that ae 21 comprehensive cancer centers in the United States, and its structure at the end of 3 years of data collection are described. Functions of the data system are detailed in terms of input and output. It is concluded that the short-run objective of establishing a data system to provide high-quality patient data that ae 21 comprehensive cancer centers in the United States, and its structure at the end of 3 years of data collection are described. Functions of the data system are detailed in terms of input and output. It is concluded that the short-run objective of establishing a data system to provide high-quality patient data that are comparable among cancer centers has been largely accomplished. Moreover, the very process of setting up the national data system has benefited the participating centers by upgrading their individual cancer registries. For the future, the goal is to realize the research potential of this new cooperative data collection mechanism, as well as the accumulating data themselves. Progress toward the long-term goal is just beginning.

Diet in the epidemiology of carcinoma of the prostate gland.

In vivo, in vitro, prospective, and retrospective epidemiologic inquiries have suggested that retinoids inhibit cancer, and fats have been hypothesized to enhance and ascorbic acid to reduce cancer risk. Comparison of 260 patients from Buffalo with cancer of the prostate gland was made with two different control series of similar size and age distribution. Regardless of the control group, risk of prostate cancer gained with increases in ingestion of retinoids, animal fats, and vitamin C. These anomalous findings may be due to peculiarities in methodology. From the possible specificity of effect of the nutrients studied, as shown in experimental animals and in vitro, a hypothesis could be made that a substance like vitamin A or C, which may inhibit certain cancers, also may enhance risk of other cancer types or have neither effect.

Relative reliability of five serially measured markers for prognosis of progression in prostate cancer.

During an 8-year period, 1,065 serum specimens were collected from 79 patients with prostate cancer of stages B2 to D1 (group I) and 51 patients with newly diagnosed stage D2 prostate cancer (group II) to evaluate statistically the relative reliability of elevated tumor-associated markers for progressive disease in prostate cancer. Forty of the group I patients and 21 of the group II patients presented a clinical progression of disease during follow-up. With the use of Gail's modification of Cox's regression model, serial acid phosphatase (AcP), total alkaline phosphatase (TAP), bone alkaline phosphatase (BAP), prostatic acid phosphatase (PAP), and prostate-specific antigen (PA) were analyzed. Results from group I patients revealed that only PA (P = .0002) and PAP (P = .0684) were prognostically important markers for detection of imminent disease progression. However, all markers were prognostically important in group II patients. Comparative studies indicated that PA (P = .0052) and PAP (P = .0359) were the more reliable markers for group I patients, whereas PA (P less than .0001), BAP (P = .0007), and PAP (P = .0206) were the more reliable markers for group II patients. Multivariate analyses revealed that, after adjustment for the effect of PA, no other marker was significantly related to the risk of progression. Elevated PA levels were predictive of increased risk 6 months before disease progression in group I patients only (P less than .0001). Overall, the apparent order of prognostic reliability for disease progression was found to be PA greater than PAP greater than BAP greater than AcP greater than TAP.

Prognostic factors in patients with advanced stage prostate cancer.

The relationships of 13 potential prognostic factors to objective response to treatment and survival time were investigated, using data gathered on 1,020 patients with advanced stage prostate cancer who have participated in the clinical trials of the National Prostatic Cancer Project. Multivariate statistical analyses revealed that previous hormone response status, analgesics, pain, elevated acid phosphatase, and anemia were the important, independent prognostic factors for objective response to treatment. For survival time, the significant prognostic factors were previous hormone response status, anorexia, elevated acid phosphatase, pain, elevated alkaline phosphatase, obstructive symptoms, tumor grade, performance status, anemia, and age at diagnosis. It is recommended that future treatment protocols for advanced stage prostate cancer take into account heterogeneity of the treatment groups with respect to these factors, either through the design of the protocol, or at the time of analysis.

Antitumor activity of Corynebacterium parvum and retinyl palmitate used in combination on the Lewis lung carcinoma.

The effects of Corynebacterium parvum and retinyl palmitate given at various levels, schedules, and routes of administration on primary Lewis lung carcinoma and its metastases have been evaluated in C57BL/6J mice given s.c. inoculations of 5 X 10(5) tumor cells. Single i.v., but not i.p., s.c., or i.m., administration of C. parvum (0.35 mg/mouse given on Days 0, 1, or 3) reduced growth of tumor and prolonged survival time. Retinyl palmitate (3000 IU/mouse/day) given alone i.p. either before, after, or both before and after tumor inoculation showed no effect on tumor growth, survival of mice, or lung metastases. The combination of retinyl palmitate i.p. (6 daily injections of 1500 IU/mouse after tumor implantation) and C. parvum (0.175 mg/mouse) given i.v. resulted in an increase in life span over control of 146% and appeared to be therapeutically synergistic. This combination produced 90-day cures in about 20% of the treated animals, all of which were found to be tumor free. Two nonparametric statistical procedures, the Kruskal-Wallis and the Dunn test, were used to assess the effects of treatments on survival time and tumor growth and may be generally applicable to animal tumor studies. They provide multiple comparisons of different treatments and allow the inclusion of long-term survivors into the analysis.

Phase I study of high-dose methotrexate with thymidine and low-dose leucovorin.

A total of 15 patients with advanced neoplastic disease, 13 with different solid tumors, one with lymphoma, and one with acute lymphocytic leukemia, underwent treatment consisting of continuous infusion of methotrexate (2 g/sq m/day) with concomitant thymidine (8 g/sq m/day) and leucovorin (1 mg/sq m/day). The dose of methotrexate was increased progressively by lengthening the methotrexate infusion from 2 to 7 days. After cessation of methotrexate infusion, thymidine and leucovorin were continued until the plasma level of methotrexate decreased to 2 X 10(-8) M. Toxicity was mucositis (23 of 27 evaluable courses), leukopenia (15 of 26 evaluable courses), thrombocytopenia (10 of 26 evaluable courses), renal and hepatic toxicity and diarrhea. Plateau levels of plasma methotrexate or methotrexate plasma half-life did not correlate with toxicity.

Intensive remission consolidation therapy in the treatment of acute nonlymphocytic leukemia.

A pilot study was conducted to determine the possible efficacy and the toxicities associated with the administration of four courses of intensive consolidation chemotherapy to patients with acute nonlymphocytic leukemia in remission. All therapy was completed within 6 months. The median duration of remission was 22 months, with 45+% of patients in remission at 3 years and few relapses to date thereafter. Sixty percent of patients experienced significant side effects after each course of therapy. The therapy appeared to be particularly efficacious for patients less than 45 years of age, since 65% are alive at 3 years and there is no projection for a median duration of remission as yet. The cytogenetic characteristics of the leukemic cells, the percentage of S phase cells, and the height of the WBC count were the most important prognostic characteristics at diagnosis.

Impact of interferon beta-1a on neurologic disability in relapsing multiple sclerosis. The Multiple Sclerosis Collaborative Research Group (MSCRG).

BACKGROUND AND OBJECTIVE: A phase III double-blind, placebo-controlled clinical trial demonstrated that interferon beta-1a (IFN beta-1a) (Avonex, Biogen) significantly delayed progression of disability in relapsing MS patients. The primary clinical outcome was time from study entry until disability progression, defined as > or = 1.0 point worsening from baseline Kurtzke Expanded Disability Status Scale (EDSS) score persisting for at least two consecutive scheduled visits separated by 6 months. The objective of this study was to examine the magnitude of benefit on EDSS and its clinical significance. METHODS: Post hoc analyses related to disability outcomes using data collected during the double-blind, placebo-controlled phase III clinical trial. RESULTS: (1) Clinical efficacy related to disability did not depend on the definition of disability progression. A significant benefit in favor of IFN beta-1a was observed when > or = 2.0 point worsening from baseline EDSS was required or when worsening was required to persist for > or = 1.0 year. (2) Placebo recipients who reached the primary clinical outcome worsened by a larger amount from baseline EDSS than did IFN beta-1a recipients who reached the primary study outcome. (3) Significantly fewer IFN beta-1a recipients progressed to EDSS milestones of 4.0 (relatively severe impairment) or 6.0 (unilateral assistance needed to walk). (4) Cox proportional hazards models demonstrated that the only baseline characteristic strongly correlated with longer time to disability progression was IFN beta-1a treatment. CONCLUSIONS: The primary clinical outcome for the IFN beta-1a clinical trial underestimated clinical benefits of treatment. Results in this report demonstrate that IFN beta-1a treatment is associated with robust, clinically important beneficial effects on disability progression in relapsing MS patients.

Cerebrospinal fluid abnormalities in a phase III trial of Avonex (IFNbeta-1a) for relapsing multiple sclerosis. The Multiple Sclerosis Collaborative Research Group.

BACKGROUND AND OBJECTIVE: This report provides results of CSF analyses done in a subset of relapsing remitting MS patients participating in a placebo-controlled, double-blind, phase III clinical trial of IFNbeta-Studies supported by the National Multiple Sclerosis Society (grants RG2019, RG2827),a (Avonex , Biogen). The clinical trial demonstrated that IFNbeta-1a treatment resulted in significantly reduced disability progression, annual relapse rate, and new brain lesions visualized by cranial magnetic resonance imaging. The objectives of the current study were to determine: (a) whether CSF abnormalities in MS patients correlated with disease or MRI characteristics, and (b) effects of IFNbeta-1a therapy on these CSF abnormalities. METHODS: CSF was analyzed from 262 (87%) of the 301 study subjects at entry into the clinical trial, and a second CSF sample was analyzed from 137 of these 262 subjects after 2 years of therapy. CSF cell counts, oligoclonal bands (OCB), IgG index, and free kappa light chains were measured using standard assays. Baseline CSF results were compared with demographic, disease, and MRI parameters. Differences in on-study relapse rate, gadolinium enhancement, and EDSS change according to baseline CSF status was used to determine the predictive value of CSF for subsequent clinical and MRI disease activity. Change in CSF parameters after 104 weeks were used to determine the effects of treatment. RESULTS: (1) At study baseline, 37% of the subjects had abnormal CSF WBC counts, 61% had abnormal levels of CSF free kappa light chains, 84% had abnormal IgG index values, and 90% were positive for OCB. (2) Baseline IgG index, kappa light chains, and OCB showed weakly positive, statistically significant correlations with Gd-enhanced lesion volume and T2 lesion volume. WBC showed a statistically significant correlation with Gd-enhancing lesion volume but was uncorrelated with T2 lesion volume. (3) There was an associated between baseline CSF WBC counts and on-study clinical and MRI disease activity in placebo recipients. (4) IFNbeta-1a treatment resulted in significantly reduced CSF WBC counts, but there was no treatment-related change in CSF IgG index, kappa light chains, or OCB, which remained relatively stable over time in both patient groups. CONCLUSIONS: The current study documents significant reductions in CSF WBC counts in patients treated with IFNbeta-1a for 104 weeks. This finding is considered relevant to the therapeutic response, since CSF WBC counts were found to be positively correlated with subsequent clinical and MRI disease activity in placebo-treated relapsing MS patients.

Recognition of drug resistance during remission induction therapy for acute non-lymphocytic leukemia: utility of day 6 bone marrow biopsy.

While the majority of patients under 70 years of age with acute non-lymphocytic leukemia enter remission when treated with a combination of cytosine arabinoside and an anthracycline antibiotic, 20-45% of patients do not. The reasons for treatment failure in these patients vary from drug resistant disease to death from infection or bleeding shortly after remission induction therapy is initiated. Clearly, more intensive remission induction therapy should be administered only to those patients for whom the therapy being employed is of insufficient intensity. Bone marrow biopsies after six days of therapy have been performed on 53 patients who received 65 courses of remission induction therapy. Eighty-eight per cent of the remissions occurred in patients whose marrow cellularity was less than 62.5% on day 6 while 78% of patients who had drug resistant disease had day 6 marrow cellularities which exceeded 62.5%. Hence, a bone marrow biopsy performed after six days of therapy permits the recognition of the majority of patients who will enter complete remission or alternatively who need more aggressive therapy.

Using admission characteristics to predict return to the community from a post-acute geriatric evaluation and management unit.

OBJECTIVE: To compare the Cumulative Illness Rating Scale (CIRS) and the Nursing Severity Index (NSI) as independent predictors of discharge outcome from a post-acute GEM unit and to define a multivariate model for predicting the same outcome. DESIGN: Retrospective chart review for the entire sample. The sample was split into two cohorts, a derivation cohort (n = 298) and a validation cohort (n = 154). SETTING: A 20-bed, post-acute GEM unit in a nonproprietary skilled nursing facility. PARTICIPANTS: All 452 patients admitted to the GEM from the unit's inception in December 1994 until January 1998. MEASUREMENT: Demographics, CIRS, NSI, functional status, and social support variables were measured using data available on admission to the GEM unit. The discharge outcome was dichotomized as return to the community or not. RESULTS: A total of 99.7% of the individuals in the derivation cohort were living in the community before the index hospitalization; 75.8% of patients in the derivation cohort returned to the community. The NSI, individual "severe" items from the CIRS, age, and social support were in the final logistic regression model fitted to the derivation cohort. A total of 87.7% of the observed discharge outcomes were predicted when the model was applied to the validation cohort and the calculated probability of return to the community. CONCLUSIONS: Variables for severity of illness, function, social support, and age combined into a logistic regression equation that predicted more than 80% of the dichotomized discharge outcome in the derivation cohort. The proportion of discharge outcomes that were predicted with the validation cohort remained high at 87.7%. The NSI and CIRS were each important to a model that is anticipated to refine the selection of geriatric patients for post-acute services.

Antibiotic use, hospital admissions, and mortality before and after implementing guidelines for nursing home-acquired pneumonia.

OBJECTIVES: To compare two strategies for implementing guidelines for nursing home-acquired pneumonia (NHAP) and to measure outcomes associated with treatment in accordance with the guidelines. DESIGN: Randomized controlled trial. SETTING: Ten skilled nursing facilities (SNFs) from a single metropolitan area. PARTICIPANTS: Patients with an episode of pneumonia acquired more than 3 days after admission to SNF (N = 350): 226 preintervention episodes of pneumonia and 116 postintervention episodes. INTERVENTIONS: Multi-faceted education intervention including small-group consensus process limited to physicians and a similar intervention that included physicians and nurses within randomly selected SNFs. MEASUREMENTS: Antibiotic use at diagnosis compared with the guidelines, hospital admission, severity of pneumonia, and 30-day mortality. RESULTS: Data were complete for 344 episodes of NHAP. For the preintervention group (n = 226), 62.2% (79/127) of the episodes were treated with parenteral antibiotics (PA) when PA were recommended by the guidelines and 57.6% (57/99) of episodes were treated with oral antibiotics (OA) when OA were indicated by the guidelines. Postintervention, treatment with PA and OA according to the guidelines was not significantly different between the two groups of randomized SNFs. A multivariate analysis comparing PA use pre- and postintervention for all SNFs, adjusted for variation in the frequency and severity of pneumonia, found significantly more of the postintervention episodes were treated with PA in accordance with the guidelines (P < .02). A preintervention significant difference in 30-day mortality observed between episodes with indications for PA (37.8% (48/127)) and episodes with indications for OA (6.1% (6/99)) (P < .001) was not present postintervention (11.5% (6/52); (23.8% (15/64); P = .06). There was no significant difference in 30-day mortality preintervention and postintervention for episodes with guideline indications for OA (P = .35) or for PA (P = .05) (P = .16 for multivariate analysis). The difference in PA use was not associated with significant differences in hospital admissions for episodes on NHAP. CONCLUSION: The increase in the use of PA provides evidence that care within SNFs can be significantly changed using standard quality improvement techniques. Use of the guidelines did not significantly affect mortality. The addition of a practical severity of NHAP model or a change in reimbursement structure may enhance the guidelines' impact on hospitalization for NHAP. The financial benefits available with use of the guidelines will be limited unless the guidelines contribute to a reduction in rates of hospitalization.

Brain MRI lesions and atrophy are related to depression in multiple sclerosis.

It is unclear whether brain MRI lesions are associated with depression in multiple sclerosis (MS). Neurological dysfunction in depressed (n= 19) and non-depressed (n = 29) MS patients was rated by expanded disability status scale (EDSS). EDSS was weakly predictive of the presence of (p = 0.03) and severity of (p = 0.01) depression. After correcting for EDSS, the presence of depression was predicted by superior frontal and superior parietal hypointense TI lesions (p<0.01); the severity of depression was predicted by superior frontal, superior parietal and temporal TI lesions, lateral and third ventricular enlargement, and frontal atrophy (p<0.01). Depression was not related to bright T2 lesions or enhancement. We conclude that atrophy and cortical-subcortical disconnection due to frontal and parietal white matter destructive lesions may contribute to depression in MS.

Results of another trial of chemotherapy with and without hormones in patients with newly diagnosed metastatic prostate cancer.

From July, 1980, to June, 1983, 319 patients with newly diagnosed metastatic prostatic cancer were randomized to one of three treatment protocols: diethylstilbestrol (DES) or bilateral orchiectomy, cyclophosphamide plus 5-fluorouracil plus DES, and estramustine phosphate (Emcyt). Ninety-three per cent of 296 patients were eligible for evaluation. This report shows no difference in survival, disease-free progression time, or status regarding pain at entry. Other prognostic factors failed to reveal any difference within any of the treatment protocols.

Comparison of Megace, Stilphostrol, Megace plus DES, or streptozotocin in metastatic prostatic cancer in patients with hormonal failure and prior radiotherapy.

The National Prostatic Cancer Project from 1982 to 1985 evaluated several treatments for metastatic prostatic cancer patients who had a history of prior radiotherapy and were refractory to hormone manipulation. The treatments studied were megestrol acetate (Megace), Megace plus diethylstilbestrol (DES), diethylstilbestrol diphosphate (Stilphostrol), and streptozotocin. While the four treatment arms did not differ significantly with respect to survival, there was a small but significant difference in progression-free survival among the treatment groups. These patients are difficult to treat and have many secondary problems, and perhaps future studies of current and new agents should focus more on subjective and other secondary benefits for them.

Pattern of care and follow-up of stages A1, B1 prostatic cancers from multicenter group, the National Prostatic Cancer Treatment Group (NPCTG).

In 1981, the National Prostatic Cancer Treatment Group began an open survey of available A1, B1 prostatic adenocarcinomas to determine outcome and clinical characteristics. Their report as of September, 1985, summarizes the outcome and important features of the survey. The majority of A1 cases had a low tumor grade I and were followed. Stage B1 received surgery or radiation generally. The B1 tumor grade was approximately one-third grade I, II, or III-IV. Presently, symptoms differ, as would be expected. Follow-up data to date have indicated no major changes. In some of the special study cases (12/52), the stage was changed as a result of the central laboratory review.