Test-set training improves the detection rates of invasive cancer in screening mammography

AIM

To investigate if mammographic test-set participation affects routine breast cancer screening performance.

MATERIALS AND METHODS

Clinical audit data between 2008 and 2018 were collected for 35 breast screen readers who participated in the BreastScreen Reader Assessment Strategy (BREAST) and 22 readers with no history of test-set participation. For BREAST readers, the annual audit data were divided according to the year they completed their first test set, and the same years were used randomly to align and divide the data of non-BREAST readers into pre- and post-test set periods. Multiple audit parameters were inspected retrospectively for the two cohorts to identify how their reading performance has evolved in screening mammography.

RESULTS

Investigating 2 calendar years before and after test-set participation, BREAST and non-BREAST readers recalled lower rates of women in the latter period (p=0.03 and p=0.02, respectively). They also improved their positive predictive value (PPV; p=0.01 and p=0.02, respectively). BREAST readers additionally improved their detection rates of invasive cancer (p=0.02) and all cancers (p=0.01). In an extended 3-year comparison, similar improvements occurred in the recall rate for BREAST (p=0.02) and non-BREAST readers (p=0.02) and in PPV (p=0.001, 0.01, respectively); however, improvements in detection rates also occurred exclusively in BREAST readers' performance for invasive cancer (p=0.04), DCIS (p=0.05), and all cancers (p=0.02); however, significant improvements in detection did not involve <15 mm invasive cancers in both periods. Meanwhile, non-BREAST readers demonstrated a decrease in sensitivity (p=0.02).

CONCLUSION

Participation in test sets is linked to over-time improvements in most audit-measured cancer detection rates.

Clinical performance progress of BREAST participants: the impact of test-set participation

AIM

To investigate if positive changes in the clinical performance of radiologists are associated with reading mammographic test sets.

MATERIALS AND METHODS

This study investigated the clinical audit history for a cohort of 39 participants in the BreastScreen Reader Assessment Strategy who have read for BreastScreen New South Wales in the period between 2010 and 2018, inclusively. Based on the year in which each radiologist completed his or her first test set, data of multiple clinical audit metrics from two calendar years before test-set reading were compared against similar data from three different periods after test-set completion. The same process was repeated after dividing radiologists into two subgroups based on their median screen-reading volume (3,688), to test if experience is a determinant of post-test set performance.

RESULTS

On average, radiologists showed significant improvements (p<0.05) in the recall rate for subsequent screening rounds, in positive predictive value 1 (PPV1), and in specificity. When dividing radiologists based on their average annual reading volume, radiologists with higher reading numbers demonstrated similar significant improvements in the recall rate and in PPV1. In addition, they showed significant improvements in the detection rates of invasive breast cancer and ductal carcinoma in situ (DCIS). In contrast, the radiologists with lower reading volume indicated significant changes in the recall rate and in PPV1, both accruing in one of the three compared periods.

CONCLUSION

Mammographic test-set participants improve over time in identifying normal breast screens and detecting breast cancer in association with reading higher volumes of breast screening cases.

Increased COX-2 expression in epithelial and stromal cells of high mammographic density tissues and in a xenograft model of mammographic density

Mammographic density (MD) adjusted for age and body mass index is one of the strongest known risk factors for breast cancer. Given the high attributable risk of MD for breast cancer, chemoprevention with a safe and available agent that reduces MD and breast cancer risk would be beneficial. Cox-2 has been implicated in MD-related breast cancer risk, and was increased in stromal cells in high MD tissues in one study. Our study assessed differential Cox-2 expression in epithelial and stromal cells in paired samples of high and low MD human breast tissue, and in a validated xenograft biochamber model of MD. We also examined the effects of endocrine treatment upon Cox-2 expression in high and low MD tissues in the MD xenograft model. Paired high and low MD human breast tissue samples were immunostained for Cox-2, then assessed for differential expression and staining intensity in epithelial and stromal cells. High and low MD human breast tissues were separately maintained in biochambers in mice treated with Tamoxifen, oestrogen or placebo implants, then assessed for percentage Cox-2 staining in epithelial and stromal cells. Percentage Cox-2 staining was greater for both epithelial (p = 0.01) and stromal cells (p < 0.0001) of high compared with low MD breast tissues. In high MD biochamber tissues, percentage Cox-2 staining was greater in stromal cells of oestrogen-treated versus placebo-treated tissues (p = 0.05).

Topographic position of forelimb motoneuron pools is conserved in vertebrate evolution

The neuromotor conservatism hypothesis predicts that neuromotor patterns in homologous tetrapod muscles are conserved evolutionarily despite the musculoskeletal modifications of vertebrate limbs. A complete description of the anatomical organization of the neurons innervating homologous limb muscles is a prerequisite to any test of the neuromotor conservatism hypothesis. This study uses the retrograde neuronal tracer WGA-HRP to selectively label the motor neuron pools of seven homologous forelimb muscles in mice (Mus musculus) and iguanas (Iguana iguana): Mm. pectoralis, spinodeltoideus, biceps brachii, lateral and long heads of triceps brachii, and the supraspinatus and infraspinatus (in mice) or their reptilian homolog, the supracoracoideus (in iguanas). In vertebrates, motoneurons are arranged in longitudinal columns of cells in the ventral horn of the spinal cord. Mouse motor pools average 1,952 microns in length, except the pectoralis pool which averaged 2,949 microns in length. Iguana pools average 3,196 microns in length. The number of neurons per pool ranged from 70-199 in mice and from 58-114 neurons in iguanas. In both iguanas and mice the motor pools for the spinodeltoids, biceps, and the supracoracoideus (or its mammalian homologs) lie anterior to the pectoralis and triceps motor pools. In the transverse plane, the pectoralis pool lies medial to those of the triceps. The pools of the biceps and spinodeltoids are located dorsal and lateral to those of the pectoralis and supracoracoideus (or its homologs in mammals). The resulting motor pool maps support the hypothesis that the anatomical organization of motoneurons in ancestral reptiles has been retained in these two tetrapod descendents.

Once daily intranasal fluticasone propionate is effective for perennial allergic rhinitis

The efficacy of intranasal fluticasone propionate 200 micrograms once daily or 100 micrograms twice daily in treating perennial allergic rhinitis was evaluated in a randomized, double-blind, placebo-controlled study of 24 weeks' duration in 365 patients. Clinician-rated and patient-rated total nasal symptom severity scores were improved within 1 week of treatment with either regimen of fluticasone propionate and improvement was maintained over the 24-week treatment period. Clinician-rated overall evaluation indicated a significantly better response in the two fluticasone propionate groups compared with the placebo group. All efficacy evaluations indicated no difference in response between the fluticasone propionate 200 micrograms once-daily and 100 micrograms twice-daily groups. Patients in both fluticasone propionate groups had significantly less nasal obstruction upon awakening than the placebo group at all assessment periods. Fewer patients in either fluticasone propionate group used antihistamine rescue medication compared with the placebo group. The percentage of patients with nasal eosinophils and basophils at the end of the 24-week treatment period was significantly lower in both fluticasone propionate groups compared with the placebo group. Safety evaluations indicated that intranasal fluticasone propionate was as safe as placebo when given as 200 micrograms once daily or 100 micrograms twice daily. The incidence of drug-related adverse events was similar among the fluticasone propionate and placebo groups except for the incidence of epistaxis and blood in nasal mucus which was somewhat higher in the fluticasone propionate twice-daily group. There was no changes in the opthalmic examinations to suggest corticosteriod-induced posterior subcapsular cataract formation.(ABSTRACT TRUNCATED AT 250 WORDS)

Current status of imaging indeterminate renal masses

In 1986 Bosniak proposed a classification of cysts and cystic renal masses in an attempt to define precisely the radiologic findings for lesions not requiring further evaluation and for those that should be explored surgically in an attempt to salvage normal renal parenchyma. This classification has been extremely useful in expanding the number of patients treated conservatively. The following entities can be considered benign and require no further evaluation: the classic simple cyst (Bosniak category 1), a cyst with benign calcification (see Fig. 1A and B), a hyperdense cyst (see Fig. 2), and a cyst with thin (less than or equal to 1mm) septations (see Fig. 5A; Bosniak category 2). When any of the following features are present, further evaluation is warranted: aggressive calcifications (see Fig. 1C-E), abnormal density not fulfilling the criteria of a hyperdense cyst (see Figs. 3 and 4), or nodular septations (see Fig. 5B and C), or wall thickening (see Fig. 7; Bosniak) category 3). Small masses that cannot be characterized accurately also require further evaluation. Multiloculated masses(see Fig. 9) require surgery (Bosniak category 3). Most cases of multiple localized renal cysts can be distinguished from multiloculated masses and do not require surgery (see Fig. 10). Evaluation of cyst fluid by MR imaging has not been proved reliable in differentiating benign and malignant masses. MR imaging will become more useful when its spatial resolution equals that of CT. Masses that remain indeterminate after careful evaluation by ultrasonography and CT scanning can be evaluated additionally by angiography or cyst puncture. Management options for persistent enigmatic masses include follow-up radiologic studies, exploration, local excision, and nephrectomy.

Plasma level studies of penbutolol after oral dose in man

Plasma levels of penbutolol (HOE 893d) were determined in eight healthy adult male subjects after oral administration of 50-mg capsules. Fast absorpiton of the drug from the gastrointestinal tract was indicated by the rapid increase in plasma levels during the absorption phase, with a peak time at about 1 hour after dosing in all subjects. After the peak level, plasma concentrations declined biexponentially, with an average half-life of 2.5 and 27 hours for the fast and slow disposition phases, respectively. These values were in good agreement with data previously found for this drug. Cumulative excretion of intact drug in the urine of the eight subjects during 72 hours after dosing was less than 4 per cent, except for one subject who excreted 9.82 per cent of the dose. Large individual variations were found for area under the plasma level curves, disposition rates, and amounts of intact drug excreted in the urine. Significant pharmacologic effects were noted in all eight subjects at the 50-mg dose level, and mild side effects were evident in one half of these subjects. The average drop in blood pressure and pulse rate for all subjects was 26/18 mm Hg and 19 beats per minute, respectively.