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Biomedical subjects

R Gelman

Publications and source records attributed to R Gelman.

At least 55 records · Page 3Linked to original sources
PubMed1994

The relationship between microscopic margins of resection and the risk of local recurrence in patients with breast cancer treated with breast-conserving surgery and radiation therapy.

BACKGROUND: The relationships among the involvement of tumor at the final margins of resection, the presence of an extensive intraductal component (EIC), and the risk of local recurrence are important considerations in patients treated with conservative surgery and radiation therapy for early stage breast cancer but have not been defined adequately. METHODS: Between 1982 and 1985, 885 patients were treated for clinical Stage I or II invasive breast cancer. The study population was limited to 181 patients with an infiltrating ductal carcinoma who received a radiation dose to the surgical site of 60 Gy or greater, whose final microscopic margins of resection were evaluable, and who had at least 5 years of follow-up. A positive margin was defined as tumor present at the inked margin of resection, a close margin as tumor within 1 mm of the inked margin, and a negative margin as no tumor within 1 mm of the inked margin. A focally positive margin was defined as tumor at the margin in three or fewer low-power fields. In 157 patients (87%), the tumor was evaluable for the presence or absence of an EIC. The median follow-up was 86 months. RESULTS: In 12 of 181 patients (7%), a recurrence developed at or near the primary site (true recurrence/marginal miss [TR/MM]) within 5 years. The 5-year rate of TR/MM (with 95% confidence intervals) among patients with negative, close, focally positive, and more than focally positive margins was 0% (0-4%), 4% (0-20%), 6% (1-17%) and 21% (10-37%), respectively. Patients with positive margins also were more likely to have a distant failure within 5 years (14%, 8%, 25%, and 32% in the four groups, respectively). However, patients with positive margins more often had positive axillary lymph nodes than patients with negative or close margins (59% vs. 38%, P < 0.02). The 5-year rate of TR/MM was 20% for patients with an EIC-positive tumor and 7% for patients with an EIC-negative tumor. However, among the 127 patients with an EIC-negative tumor, the 5-year rate of TR/MM was less than 10% in all margin groups. Among the 30 patients with an EIC-positive tumor, the 5-year rate of TR/MM was 0% when margins were negative or close but 50% when margins were more than focally positive. CONCLUSIONS: These results provide support for the use of breast-conserving surgery and breast irradiation in all patients with uninvolved margins, whether the tumor is EIC-positive or EIC-negative. This study suggests that breast-conserving therapy (including a radiation boost to the primary site) also may be a reasonable option for some patients with an EIC-negative tumor and margin involvement.

Breast↗
PubMed1994

Rate of relapse following treatment for localized prostate cancer: a critical analysis of retrospective reports.

PURPOSE: Controversy exists over the optimal treatment for patients with clinically localized prostate cancer. Almost all of the treatment results are from non-randomized trials and interseries comparison is difficult since the apparent success of a treatment, as judged by the actuarial freedom from relapse and survival data, depends on patient selection criteria and post-treatment evaluation, in addition to the efficacy of the therapeutic intervention. In this report the calculation of a hazard function is used to estimate and compare the rate of relapse for the different treatments. METHODS AND MATERIALS: Clinical reports from major surgery and radiation oncology treatment institutions were analyzed. The actuarial recurrence data were used to calculate the annual rate of recurrence within each series. RESULTS: For all but the lowest volume tumors, patients continue to be at risk of relapse for as long as these series have been followed. Despite the heterogeneity of patient populations, the recurrence rates by stage are similar for patients treated with surgery or irradiation. This result is consistent with pathologic data from prostatectomy specimens which indicate that for lesions > 12 cm3 (approx. 3 cm in diameter) there is high likelihood of extraprostatic disease. CONCLUSION: Treatment outcome for patients with localized prostate cancer may be more dependent on the inherent tumor biology than the particular type of treatment. Accordingly, the expectation and recommendation of a treatment must take into consideration the continued risk of relapse with either radiation therapy or surgery. There are, as yet, insufficient data regarding the impact of screening and earlier diagnosis on the curability of patients with localized prostate cancer.

Humans↗
PubMed1994

Reinduction with the same cytostatic treatment in patients with metastatic breast cancer: an Eastern Cooperative Oncology Group study.

PURPOSE: To investigate the therapeutic value of reinduction with the same cytostatic treatment that had been used in induction treatment for women with metastatic breast cancer. MATERIALS AND METHODS: One hundred six women with metastatic breast cancer were given dibromodulcitol (mitolactol), doxorubicin, vincristine, tamoxifen, and fluoxymesterone (DAVTH) for 6 months of induction treatment, then randomized to receive one of two chemotherapy regimens if they had obtained an induction partial response (PR) or no change (NC), or to receive observation versus chemotherapy if they had obtained an induction complete response (CR). Patients were then retreated with DAVTH reinduction after relapse. RESULTS: Seventy-four patients were eligible or had minor reasons for ineligibility. Severe or life-threatening toxicity was documented in 46%, and lethal toxicity in 4%. Eighteen percent had a response on reinduction (zero of 16 induction nonresponders, 15% induction PR, 44% induction CR). The median time to treatment failure (TTF) from reinduction was 3 months, and the median survival duration from reinduction was 14 months. In a logistic model, factors associated with more reinduction responses were observation after induction CR (P = .002) and age greater than 55 years (P = .04). Time since induction was not significant. CONCLUSION: Reinduction of response after treatment failure remains a therapeutic problem. The need for better salvage treatment underlines the importance of developing new regimens.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1994

Relationship of patient age to pathologic features of the tumor and prognosis for patients with stage I or II breast cancer.

PURPOSE: This analysis was performed to clarify the relationship of young age at diagnosis to the pathologic features of the tumor and prognosis in patients with early-stage breast cancer. PATIENTS AND METHODS: We retrospectively analyzed data from 1,398 patients with American Joint Committee on Cancer Staging stage I or II breast cancer treated by breast-conserving therapy between 1968 and 1985. One hundred seven patients were younger than 35 years at the time of diagnosis. The median follow-up duration for the 1,032 survivors was 99 months. RESULTS: Patients younger than 35 years had a significantly higher overall recurrence rate (P = .002), as well as a greater risk for developing distant metastases (P = .03), when compared with older patients. The cancers in younger patients more commonly showed factors associated with a worse prognosis (including grade 3 histology, lymphatic vessel invasion [LVI], necrosis, and estrogen receptor [ER] negativity) as compared with older patients. In a proportional hazards model that included clinical and treatment-related variables, as well as these pathologic features, age younger than 35 years remained a significant predictor for time to recurrence (relative risk [RR], 1.70), time to distant failure (RR, 1.60), and overall mortality (RR, 1.50). CONCLUSION: Breast cancer patients younger than 35 years have a worse prognosis than older patients. This difference is only partially explained by a higher frequency of adverse pathologic factors seen in younger patients.

Actuarial Analysis↗
PubMed1993

Assessment of the effects of instrumentation, monoclonal antibody, and fluorochrome on flow cytometric immunophenotyping: a report based on 2 years of the NIAID DAIDS flow cytometry quality assessment program.

This study of the effect on CD4%, CD8%, CD3+8+%, and CD3% of flow cytometer, monoclonal antibody, and fluorochrome was based on 71 whole-blood samples, each evaluated by 42 to 59 laboratories during 2 years of a flow cytometry quality assessment program. For the 24 HIV-positive specimens, FACScans produced significantly lower CD4% values than EPICS-Cs or EPICS Profiles, and for the 47 HIV-negative specimens, FITC was associated with significantly lower CD4% values than PE or RD1, but differences were never larger than 2% and regressions accounted for only 3-12% of the variability. The labs using the most common CD4 technique had significantly higher between-laboratory variability than all other labs grouped together. For both CD8 and CD3+8+, measurements on FACScans were significantly higher than measurements on EPICS, and measurements using Leu2 were significantly higher than measurements using T8, with regressions accounting for 12-31% of the variability. The machine differences in medians were 3-7% for labs using Leu2-FITC. It might be worthwhile to discourage the use of Leu2-FITC for measuring CD8% but no change in instrument, monoclonal antibody, or fluorochrome would greatly improve interlaboratory agreement on CD4%.

Antibodies, Monoclonal↗
PubMed1993

Prediction of CD4 count from CD4 percentage: experience from three laboratories.

OBJECTIVE: CD4 counts have been used to monitor progression of disease in HIV infection as criteria for initiation of therapy, and to stratify and follow patients in clinical trials. Recently, the Centers for Disease Control and Prevention (CDC) has made CD4 counts part of the classification of HIV disease. Because a CD4 percentage may be the only laboratory information available, this study was initiated to determine whether the correlation between CD4 percentages and CD4 counts is sufficiently high to enable these measures to be substituted for each other. DESIGN, SETTING AND PATIENTS: One thousand consecutive CD4 measurements from the University of Washington (UW) were used to create a model that was tested using datasets of 1000 CD4 measurements each from Maryland Medical Laboratories (MML) and Rush-Presbyterian-St Luke's Medical Center (Rush). The patients were not selected for age, sex, risk group or treatment. All patients from MML and Rush were known to be HIV-positive, while the HIV status of all UW patients was unknown. RESULTS: The model predicted that a patient with a CD4 percentage > or = 14% would have a CD4 count > or = 200 x 10(6)/l(if CD4 percentage of 14% was used, 9% of patients would have a CD4 count > or = 200 x 10(6)/l), and a patient with a CD4 percentage > or = 27% would have a CD4 count > or = 500 x 10(6)/l(if CD4 percentage of 27% was used, 17% of patients would have a CD4 count > or = 500 x 10(6)/l). CONCLUSIONS: These CD4 percentage correlations may be useful when a white blood cell and lymphocyte count are not available to calculate the CD4 count.

CD4-Positive T-Lymphocytes↗
PubMed1992

Lymphocyte subsets in healthy children during the first 5 years of life.

OBJECTIVE: To assess whether relative and absolute values of CD4 and CD8 lymphocytes and CD4/CD8 ratio change in relation to age, and to estimate the fifth and 95th percentiles for these values in children of various ages. PATIENTS AND METHODS: Phenotypic analysis of lymphocyte subsets was performed on blood samples from 208 healthy children, aged 1 through 59 months, using standard flow cytometric techniques. RESULTS: Regression analysis demonstrated that CD4 and CD8 lymphocyte counts declined significantly with advancing age (P less than .000001 and P = .03, respectively). Since CD4 and CD8 counts depend on total lymphocyte count, the percentage of total lymphocytes of each phenotype was also analyzed and demonstrated that the CD4 percentage was highly age dependent (P less than .000001). The CD8 percentage increased with age (P = .0001) but not as much as the CD4 percentage decreased. Median CD4 counts (fifth and 95th percentiles) for children 2 through 3, 4 through 8, 12 through 23, and 24 through 59 months of age were 2.83 (1.46 to 5.11), 2.95 (1.69 to 4.61), 2.07 (1.02 to 3.60), and 1.80 (0.90 to 2.86) x 10(9)/L, respectively. CONCLUSION: Healthy children's CD4 lymphocyte counts are considerably higher than previously established adult values. These data demonstrate that age is an important consideration in interpretation of lymphocyte subsets in children. This may be especially relevant in children who are infected with the human immunodeficiency virus, where CD4 lymphocyte values play a central role in monitoring disease progression and determining thresholds for medical interventions.

CD4-CD8 Ratio↗
PubMed1992

Preverbal and verbal counting and computation.

We describe the preverbal system of counting and arithmetic reasoning revealed by experiments on numerical representations in animals. In this system, numerosities are represented by magnitudes, which are rapidly but inaccurately generated by the Meck and Church (1983) preverbal counting mechanism. We suggest the following. (1) The preverbal counting mechanism is the source of the implicit principles that guide the acquisition of verbal counting. (2) The preverbal system of arithmetic computation provides the framework for the assimilation of the verbal system. (3) Learning to count involves, in part, learning a mapping from the preverbal numerical magnitudes to the verbal and written number symbols and the inverse mappings from these symbols to the preverbal magnitudes. (4) Subitizing is the use of the preverbal counting process and the mapping from the resulting magnitudes to number words in order to generate rapidly the number words for small numerosities. (5) The retrieval of the number facts, which plays a central role in verbal computation, is mediated via the inverse mappings from verbal and written numbers to the preverbal magnitudes and the use of these magnitudes to find the appropriate cells in tabular arrangements of the answers. (6) This model of the fact retrieval process accounts for the salient features of the reaction time differences and error patterns revealed by experiments on mental arithmetic. (7) The application of verbal and written computational algorithms goes on in parallel with, and is to some extent guided by, preverbal computations, both in the child and in the adult.

Animals↗
PubMed1992

Interobserver reproducibility in the diagnosis of ductal proliferative breast lesions using standardized criteria.

Although the categorization of proliferative breast lesions provides valuable information regarding subsequent risk of breast cancer, the ability of pathologists to classify such lesions in a reproducible fashion has not been adequately evaluated. To assess further interobserver reproducibility in the categorization of proliferative breast lesions, six pathologists each reviewed 24 proliferative ductal lesions and classified them as either usual hyperplasia (H), atypical hyperplasia (AH), or carcinoma in situ (CIS). Before evaluation of the study slides, all the participants were instructed to use the diagnostic criteria of Page and co-workers and were provided with both a written summary of these criteria and a set of teaching slides with representative examples of each type of lesion. Complete agreement among all six pathologists was seen in 14 cases (58%); five or more agreed in 17 cases (71%); and four or more arrived at the same diagnosis in 22 cases (92%). No pathologist consistently rendered more "benign" or "malignant" diagnoses than any other. After assigning numerical values for each diagnostic category (H = 1, AH = 2, CIS = 3), the scores for the group of 24 cases did not differ significantly by pathologist (p = 0.68; average score range, 1.7-2.0). Our results indicate that with the use of standardized criteria, interobserver concordance in the diagnosis of proliferative ductal breast lesions can be obtained in the majority of cases.

Breast↗
PubMed1992

Normal uptake in a gravid uterus on Tc-99m DTPA imaging.

A 17-year-old female kidney transplant patient was admitted to the hospital with a fever and right lower quadrant pain. Although she was 14 weeks' pregnant, renal DTPA imaging was performed because graft rejection was suspected. The study revealed fetal uptake of DTPA medial to the transplanted kidney. This has not been previously reported. Uptake in a normal uterus has been described using Tc-99m pertechnetate, Tc-99m glucoheptonate, and Tc-99m MDP. It is essential to recognize uptake in the gravid uterus and to differentiate it from uptake secondary to a pathologic entity.

Adolescent↗
PubMed1992

Recurrence in the breast following conservative surgery and radiation therapy for early-stage breast cancer.

This report summarizes the experience of the Joint Center for Radiation Therapy (JCRT) in treating patients with clinical stage I and II breast cancer with conservative surgery and radiation therapy. The study population consisted of 1396 patients treated between 1968 and 1985. All patients underwent a gross excision of the tumor and received breast irradiation (with or without nodal irradiation) including a "boost" to bring the primary tumor site to a total dose of at least 60 Gy. The method of treatment evolved over the study-time period. During the interval from 1968 to 1982, patients typically underwent a limited gross excision of the tumor without regard to the microscopic margins of resection. During the period 1983 to 1985, film-screen mammography, inking of specimen margins, and reexcisions for inevaluable or involved margins were more commonly performed. With a median follow-up of 80 months, the 5-year crude rate of failure in the breast (as the first site of failure) was 8% (106/1396) and the crude rate of regional nodal/distant failure (as the first site of failure) was 16% (228/1396). The time-course of failures in the breast was protracted, occurring at a fairly constant rate over the first 7 years after treatment, but still seen beyond that point. Most recurrences in the breast (75%) developed at or near the original tumor site. The most important risk factor for developing a breast recurrence was the presence of an extensive intraductal component in the tumor. The cosmetic results following treatment were excellent or good in the majority of patients (87%) and were most adversely affected by extensive surgery.(ABSTRACT TRUNCATED AT 250 WORDS)

Breast Neoplasms↗