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Biological dosimetry is an essential tool for estimating radiation dose. The dicentric chromosome assay (DCA) is currently the tool of choice. Because the assay is labor-intensive and time-consuming, strategies are needed to increase throughput for use in radiation mass casualty incidents. One such strategy is to truncate metaphase spread analysis for triage dose estimates by scoring 50 or fewer metaphases, compared to a routine analysis of 500 to 1000 metaphases, and to increase throughput using a large group of scorers in a biodosimetry network. Previously, the National Institutes for Allergies and Infectious Diseases (NIAID) and the Armed Forces Radiobiology Research Institute (AFRRI) sponsored a double-blinded interlaboratory comparison among five established international cytogenetic biodosimetry laboratories to determine the variability in calibration curves and in dose measurements in unknown, irradiated samples. In the present study, we further analyzed the published data from this previous study to investigate how the number of metaphase spreads influences dose prediction accuracy and how this information could be of value in the triage and management of people at risk for the acute radiation syndrome (ARS). Although, as expected, accuracy decreased with lower numbers of metaphase spreads analyzed, predicted doses by the laboratories were in good agreement and were judged to be adequate to guide diagnosis and treatment of ARS. These results demonstrate that for rapid triage, a network of cytogenetic biodosimetry laboratories can accurately assess doses even with a lower number of scored metaphases.

Purpose: Medical management of suspected radiation casualties requires use of multiparameter biodosimetry because no single biodosimetric measurement is sufficiently robust. This report describes the design and algorithms used in a radiation exposure assessment software application that serves as a diagnostic utility for triage and medical treatment formulation, as well as to convey psychological reassurance, for early-phase assessment of radiation exposures, and for surge response assessment for mass radiological casualties., Methods: The Armed Forces Radiobiology Research Institute's Biological Dosimetry Research Program developed the integrated multiparameter Biodosimetry Assessment Tool computer program using Microsoft Visual Basic 6 with various second party plug-ins and add-ons. Dose-predicting algorithms were adopted by analyzing data from merged databases of human radiation exposure incidents and normal controls (non-irradiated) volunteers. The results are summarized in user-friendly screens., Summary: BAT algorithms are presented and compared to other previously published dose assessment algorithms based on biological indicators (i.e., onset of vomiting, lymphocyte depletion kinetics). These new algorithms are incorporated into a computer-based program that assists responders and medical providers in recording relevant diagnostic information and assessing significant radiation exposures. It promotes early-phase (<10 d) data collection after a radiation exposure incident and provides data templates for entry of diagnostic information using multiparameter indices. It allows for recording of relevant clinical information and summarizes diagnostic information such as estimated multiparameter doses. Data can be printed and archived in accordance with civilian and military guidelines.

This is the first report of a series of adults (> 16 years of age) with pineoblastomas who had their entire neuraxis staged at the time of diagnosis. Between 1975 and 1992, seven men and four women with histologically proven pineoblastomas were evaluated at the University of California, San Francisco. The median age at diagnosis was 36 years (range, 17-59 yr). All patients presented with symptomatic hydrocephalus. One patient had a complete surgical resection, eight had subtotal resections, and two had biopsies only. One patient refused any treatment or follow-up review and died 6 months after diagnosis. The five patients with positively staged disease had progression either focally or in the spine 8 to 49 months (median, 10 mo) after initial diagnosis and died 1 to 20 months after recurrence; the median overall survival time from the date of surgery was 30 months. In contrast, all five patients with negatively staged disease were alive without disease progression after a median of 26 months of follow-up. Our retrospective review shows that the extent of disease at diagnosis seems to be an important prognostic factor for pineoblastomas, as is true for medulloblastomas and other primitive neuroectodermal tumors. Initial staging should include examination of the cerebrospinal fluid and magnetic resonance imaging of the spine. Although patients with pineoblastomas are often treated with adjuvant systemic chemotherapy after craniospinal irradiation, the benefits of this approach are unclear.

The case of a 57-year-old man with chondrosarcoma of the laryngeal cartilage is presented, occurring 16 years after radiation treatment for squamous cell carcinoma of the right true vocal cord. Chondrosarcoma of the larynx is an uncommon tumor. The location, grade, and time elapsed from initial treatment make it probably that this patient's chondrosarcoma is associated with his prior radiation treatment. However, it is a rare occurrence, this being the second case reported in the literature.