Studies of circulating hemopoietic progenitor cells in human fetal blood

High levels of committed erythroid and granulocytic/monocytic progenitor cells have been demonstrated in fresh blood obtained at fetoscopy. The fetal progenitor cells were more sensitive to appropriate stimuli (erythropoietin and colony-stimulating factor) than adult progenitor cells grown under the same conditions, and this was shown to be due to intrinsic differences in the progenitor cells at the different developmental stages.     

A comparison of the cost of various treatment methods for early cancer of the prostate

The relative costs have been determined for treating prostate cancer by radical prostatectomy, lymph node dissection with I125 implant, and external beam radiation in a large community practice. About 15% of patients were treated with the options involving surgery. The median cost of radical prostatectomy was $14,400, lymph dose dissection and I125 implant $12,000, and external beam radiation $6750 prior to October 1984 and $5600 after October 1984. None of the data indicate superior outcome by any one of these methods for Stage A or B prostate cancer. Therefore, the surgical approaches are usually not recommended except for the patient highly motivated to maintain potency who may select the I125 implant. In an era of diminishing funds for health care, the federal government, industry, and perceptive HMO's may elect to pay only for the less expensive method.     

Correlation of pre-treatment transurethral resection and prognosis in patients with stage C carcinoma of the prostate treated with definitive radiotherapy--RTOG experience

Four hundred and ninety-four patients with clinical Stage C carcinoma of the prostate, who were entered onto a phase III RTOG study, have been analyzed as to the potential effect of the pre-treatment transurethral resection (TUR) of the tumor. Treatment consisted of definitive irradiation to the prostate (6500-7000 cGy) and regional lymphatics (4500-5000 cGy). A total of 202 patients underwent pre-treatment TUR. This population was compared with the remaining 292 patients as to the rate of locoregional failure, incidence of distant metastases, disease-free survival, and survival. The TUR population fared significantly worse for all four end-points. To account for uneven distribution of recognized prognostic factors the results were then adjusted using stratified Mantel-Haenszel tests. The stratification process resulted in a reduced level of significance in the differences between the two populations. However, a trend toward a higher incidence of distant metastases could be observed within most strata. The trend was most pronounced in subpopulations characterized by Gleason score 6-7 and normal serum acid phosphatase (SAP). For the population characterized by Gleason score 6-10 and normal SAP, the differences in the incidence of distant metastases retained statistical significance. Whether these findings are secondary to tumor dissemination during TUR or are due to incompletely identified selection biases remains to be demonstrated in future (prospective) studies.     

Integration of local inputs in visual cortex

In mammalian visual cortex, local connections are ubiquitous, extensively linking adjacent neurons of all types. In this study, optical maps of intrinsic signals and responses from single neurons were obtained from the same region of cat visual cortex while the effectiveness of the local cortical circuitry was altered by focally disinhibiting neurons within a column of known orientation preference. Maps of intrinsic signals indicated that local connections provide strong and functional subthreshold inputs to neighboring columns of other orientation preferences, altering the observed orientation preference to that of the disinhibited column. However, measuring the suprathreshold response using single-cell recordings revealed only mild changes of preferred orientation over the affected region. Because strongly tuned subthreshold inputs from cortex only marginally affect the tuning of a cortical cell's output, it is concluded that local cortical inputs are integrated weakly compared to geniculate inputs. Such circuitry potentially allows for the normalization of responses across a wide range of input activity through local averaging.      

Induction chemotherapy in advanced head and neck cancer. A Radiation Therapy Oncology Group Study

Cisplatin (cis-platinum, 100 mg/m2) and fluorouracil (1000 mg/m2/d), for 120 hours' infusion every three weeks for three courses, produced a 93% overall response rate and a 54% complete clinical response at the single-institution level. The same combination was tested in the Radiation Therapy Oncology Group to evaluate the effectiveness and feasibility of this combination. An overall response rate of 86% was obtained, with a 38% complete clinical response. Only 27 of 42 patients completed planned surgery. Compliance with chemotherapy and radiation therapy was substantially better. No additional morbidity after surgical resection or postoperative radiation therapy was identified as secondary to the induction chemotherapy. We conclude that the combination of cisplatin and fluorouracil infusion is effective, with high complete clinical response rate in patients with advanced, previously untreated head and neck carcinoma.     

Radical prostatectomy or radiotherapy in carcinoma of prostate. The dilemma continues

Evaluation of the efficacy of radical prostatectomy versus radiotherapy in carcinoma of the prostate has been compromised by the scarcity of data in comparable populations. A nationwide search was conducted to compile the available data on the use of radiotherapy in lymphadenectomy-staged patients. The assessed population consists of patients with tumor confined to the gland (Stages A2 and B), negative staging lymphadenectomy, negative bone scan, and normal serum acid phosphatase level who received external beam radiotherapy with curative intent. To provide a broad spectrum of experiences, the search included patients from a large number of institutions including Stanford University, Washington University (St. Louis), those participating in the Radiation Therapy Oncology Group, and a broad range of radiotherapy practices surveyed by the PCS (Patterns of Care Study). A total of 209 patients were identified. No selection criteria other than the aforementioned were applied. The patients were treated consecutively during the survey period. In sharp contradistinction to the reported results of the VA Uro-Oncology Group the analysis indicates a less than 10 per cent probability of progression within the first five years after completion of treatment. Nationwide, the outcome of radiotherapy-treated patients appears to be equivalent to the comparable surgically treated population.