Using breast radiographers' reports as a second opinion for radiologists' readings of microcalcifications in digital mammography

Objective:

The aim of this study was to investigate a practical method for incorporating radiographers'' reports with radiologists'' readings of digital mammograms.

Methods:

This simulation study was conducted using data from a free-response receiver operating characteristic observer study obtained with 75 cases (25 malignant, 25 benign and 25 normal cases) of digital mammograms. Each of the rating scores obtained by six breast radiographers was utilized as a second opinion for four radiologists'' readings with the radiographers'' reports. A logical “OR” operation with various criteria settings was simulated for deciding an appropriate method to select a radiographer''s report in all combinations of radiologists and radiographers. The average figure of merit (FOM) of the radiologists'' performances was statistically analysed using a jackknife procedure (JAFROC) to verify the clinical utility of using radiographers'' reports.

Results:

Potential improvement of the average FOM of the radiologists'' performances for identifying malignant microcalcifications could be expected when using radiographers'' reports as a second opinion. When the threshold value of 2.6 in Breast Imaging-Reporting and Data System (BI-RADS®) assessment was applied to adopt/reject a radiographer''s report, FOMs of radiologists'' performances were further improved.

Conclusion:

When using breast radiographers'' reports as a second opinion, radiologists'' performances potentially improved when reading digital mammograms. It could be anticipated that radiologists'' performances were improved further by setting a threshold value on the BI-RADS assessment provided by the radiographers.

Advances in knowledge:

For the effective use of a radiographer''s report as a second opinion, radiographers'' rating scores and its criteria setting for adoption/rejection would be necessary.The number of mammography examinations has been increasing. In general, double reading by two radiologists is recommended in many countries, resulting in a shortage of radiologists. In order to solve this problem, the use of computer-aided detection (CADe) systems and/or reporting by radiographers as a second opinion for radiologists'' readings have been investigated. Since many research groups have demonstrated the clinical usefulness of various CADe systems,^1–6 CADe is accepted as the standard of care in the USA and is used in approximately 75% of screening examinations.^6,7 On the other hand, reporting by radiographers has been recommended as another approach to aid radiologists'' readings in several countries.^8–10 Although the use of CADe requires initial costs for introducing CADe systems, reporting by radiographers can be applied in almost all medical institutions without any additional facility costs. However, the practical utilization of radiographers'' reports has not been established because radiographers'' reading skills vary and owing to the insufficient evaluation of diagnostic accuracy provided by utilizing radiographers'' reports.The basic concept of “reporting by radiographers” was first developed by The College of Radiographers in 1997.⁸ Since the first practical guidance on reporting by radiographers was published, there have been a number of publications related to reporting by radiographers in the past decade, mainly in the UK.^10–14 To utilize radiographers'' reports more practically, a new reading protocol, double reading by two radiographers, was suggested. This reading protocol is a double reading using “non-discordant radiographer only (double) readings”, in which concordant cases are automatically recalled for assessment and discordant cases (where two readers disagree over an interpretation) are arbitrated by an experienced radiologist or breast clinician.¹⁵ Several studies confirmed the benefits of reporting by radiographers in screening mammograms, including cost effectiveness benefits.^16–20 Although a radiographer''s report is expected to be a substitute for one of the radiologists in a double-reading situation, questions remain, such as how to utilize a radiographer''s report in the most effective manner, as well as how to provide the best services to the patient without loss of quality.For reporting by radiographers to be effective, i.e., the highest cancer detection rate and the lowest recall rate, it is necessary to investigate the acceptance criteria to adopt or reject a radiographer''s report, as well as the acceptable performance level of a radiographer''s report. The aim of this study was to investigate a practical method on how a radiologist would adopt or reject a report provided by a single radiographer and to demonstrate the potential usefulness of radiologists reading digital mammograms utilizing radiographers'' reports. We used an existing free-response receiver operating characteristic (FROC) observer study^21,22 data set to simulate all possible combinations for evaluating radiologists'' performances with and without radiographers'' reports.     

Clinical outcomes of a novel therapeutic vaccine with Tax peptide‐pulsed dendritic cells for adult T cell leukaemia/lymphoma in a pilot study

Adult T cell leukaemia/lymphoma (ATL) is a human T cell leukaemia virus type‐I (HTLV‐I)‐infected T cell malignancy with poor prognosis. We herein developed a novel therapeutic vaccine designed to augment an HTLV‐I Tax‐specific cytotoxic T lymphocyte (CTL) response that has been implicated in anti‐ATL effects, and conducted a pilot study to investigate its safety and efficacy. Three previously treated ATL patients, classified as intermediate‐ to high‐risk, were subcutaneously administered with the vaccine, consisting of autologous dendritic cells (DCs) pulsed with Tax peptides corresponding to the CTL epitopes. In all patients, the performance status improved after vaccination without severe adverse events, and Tax‐specific CTL responses were observed with peaks at 16–20 weeks. Two patients achieved partial remission in the first 8 weeks, one of whom later achieved complete remission, maintaining their remission status without any additional chemotherapy 24 and 19 months after vaccination, respectively. The third patient, whose tumour cells lacked the ability to express Tax at biopsy, obtained stable disease in the first 8 weeks and later developed slowly progressive disease although additional therapy was not required for 14 months. The clinical outcomes of this pilot study indicate that the Tax peptide‐pulsed DC vaccine is a safe and promising immunotherapy for ATL.     

Organization and cellular arrangement of two neurogenic regions in the adult ferret (Mustela putorius furo) brain

In the adult mammalian brain, two neurogenic regions have been characterized, the subventricular zone (SVZ) of the lateral ventricle (LV) and the subgranular zone (SGZ) of the dentate gyrus (DG). Despite remarkable knowledge of rodents, the detailed arrangement of neurogenic regions in most mammals is poorly understood. In this study, we used immunohistochemistry and cell type‐specific antibodies to investigate the organization of two germinal regions in the adult ferret, which belongs to the order Carnivora and is widely used as a model animal with a gyrencephalic brain. From the SVZ to the olfactory bulb, doublecortin‐positive cells tended to organize in chain‐like clusters, which are surrounded by a meshwork of astrocytes. This structure is homologous to the rostral migratory stream (RMS) described in other species. Different from rodents, the horizontal limb of the RMS emerges directly from the LV, and the anterior region of the LV extends rostrally and reached the olfactory bulb. In the DG, glial fibrillary acidic protein‐positive cells with long radial processes as well as doublecortin‐positive cells are oriented in the SGZ. In both regions, doublecortin‐positive cells showed characteristic morphology and were positive for polysialylated‐neural cell adhesion molecule, beta‐III tubulin, and lamin B1 (intense staining). Proliferating cells were detected in both regions using antibodies against proliferating cell nuclear antigen and phospho‐histone H3. These observations demonstrate that the two neurogenic regions in ferrets have a similar cellular composition as those of other mammalian species despite anatomical differences in the brain. J. Comp. Neurol. 522:1818–1838, 2014. © 2013 Wiley Periodicals, Inc.     

Intracellular translocation of glutathione S-transferase pi during oligodendrocyte differentiation in adult rat cerebral cortex in vivo

Glutathione S-transferase (GST)-pi is a cytosolic isoenzyme used as a marker for mature oligodendrocytes in the mammalian brain. However, the cellular properties of GST-pi-immunoreactive [GST-pi (+)] cells in adult brain are not completely understood. We immunohistochemically demonstrated the existence of two subtypes of GST-pi (+) cells in the cerebral cortex of adult rats: one subtype exhibited GST-pi in the cytoplasm (C-type cells), while the other did mainly in the nucleus (N-type cells). The GST-pi (+) C-type cells were also immunopositive for 2',3'-cyclic nucleotide 3'-phosphodiesterase and RIP, indicating that they were mature oligodendrocytes, while the GST-pi (+) N-type cells expressed NG2, indicating that they were oligodendrocyte progenitor cells. Furthermore, observation of the fate of newly-generated cells by 5-bromodeoxyuridine-labeling revealed that the GST-pi (+) N-type cells differentiated into C-type cells. These findings indicate translocation of GST-pi from the nucleus to the cytoplasm during oligodendrocyte maturation.     

Development of gelatin flakes, a new type of anti-adhesive material: a preliminary study of in vivo rat adhesion models

To overcome the problems associated with sheet- or film-type anti-adhesive materials, we developed a new type of anti-adhesive material, gelatin flakes. We made two types of gelatin flakes with or without thermal cross-linking, and preliminarily examined their basic properties and the anti-adhesive efficacy using a rodent adhesion model. Both types of the gelatin flakes rapidly turned into gel and tightly attached the injured surfaces, absorbing the moisture and blood, when applied onto the abraded sites of rats. In addition, these flakes could be sprayed into the desired area by compressed air through a device with a long, thin tube, which could be used in laparoscopic surgery. The anti-adhesive effects of both types of gelatin flakes were similar, and both types were significantly superior compared to the non-treated group. Although further investigations are necessary, the gelatin flakes have unique and useful properties and satisfactory anti-adhesive effects, which indicate that they may be applicable in laparoscopic surgery.     

In vitro study on the removal of pemphigus antibody with immunoadsorption

The adsorbability of pemphigus vulgaris (PV) antibodies to immunoadsorbent with phenylalanine, tryptophan, and dextran sulfate as ligands was examined, PV antibodies were adsorbed to immunoadsorbents with both phenylalanine and tryptophan as ligands, in batchwise adsorption and column adsorption. PV antibodies were not adsorbed to immunoadsorbent with dextran sulfate as ligand, in column adsorption. It was also shown that the rates of decrease of normal protein fractions in column adsorption with phenylalanine as a ligand were small. Our results suggest that immunoadsorption therapy using sorbent with phenylalanine as a ligand may be useful for the treatment of PV. © 1996 Wiley-Liss, Inc.