Mammography screening for breast cancer: first year results from Helsinki and surroundings

PP2A-B55: substrates and regulators in the control of cellular functions

PP2A is a major serine/threonine phosphatase class involved in the regulation of cell signaling through the removal of protein phosphorylation. This class of phosphatases is comprised of different heterotrimeric complexes displaying distinct substrate specificities. The present review will focus on one specific heterocomplex, the phosphatase PP2A-B55. Herein, we will report the direct substrates of this phosphatase identified to date, and its impact on different cell signaling cascades. We will additionally describe its negative regulation by its inhibitors Arpp19 and ENSA and their upstream kinase Greatwall. Finally, we will describe the essential molecular features defining PP2A-B55 substrate specificity that confer the correct temporal pattern of substrate dephosphorylation. The main objective of this review is to provide the reader with a unique source compiling all the knowledge of this particular holoenzyme that has evolved as a key enzyme for cell homeostasis and cancer development.

Ultrasonography of Breast Lesions Detected in Mammography Screening

Mammography screening was carried out in 18012 women (aged 50–59) of whom 579 (3.21%) had to be recalled for clinical mammography. After completion of the clinical mammography each woman also had ultrasonography (US) with a hand-held real-time apparatus using a 7.5 MHz probe. There were 79 verified breast cancers; 32 of these were palpable and were also depicted at US, but only 29 (61.7%) of non-palpable breast cancers (n = 47) were found at US. Twenty-two of the non-palpable breast cancers were seen at US as a tumor-like lesion, 2 because of local echo-architecture distortion, and 5 only because of acoustic shadowing. The US image did not help to differentiate between malignant and benign lesions.

Effect of human variability on independent double reading in screening mammography

RATIONALE AND OBJECTIVES

To demonstrate the range of gains and losses that radiologists might experience from independent double reading in screening mammography.

METHODS

From a national random sample of radiologists, the authors formed 131 pairs. For each radiologist, the authors analyzed the increase relative to his or her individual true-positive rate (TPR) or false-positive rate (FPR), number of additional cancers detected, and change to negative biopsy rate that would result from independent double reading after pairing.

RESULTS

The average radiologist can expect an 8%-14% gain in TPR and a 4%-10% increase in FPR with pairing. For some radiologists, double reading increased the TPR with a small concomitant increase in FPR. Other radiologists, however, realized small gains in TPR with large increases in FPR. Adding the reading from a more experienced radiologist did not necessarily improve the TPR of a radiologist with less experience.

CONCLUSION

Radiologists can form complementary and noncomplementary pairs for double reading. Use of this procedure must be decided on an individual basis.

[The effectiveness of breast cancer screening in our country]

The aim of this paper is to review the current state of breast cancer screening in our country, as well as to discuss the most appropriate approaches for its development. Firstly, the impact of breast cancer in Spain is presented, as well as the current evidence about the efficacy of the screening. The major programs and initiatives addressed to promote screening are described. Finally, a few recommendations are given in order to achieve that breast cancer screening be, not only efficacious, but also effective. It is concluded that it is necessary that health and professional authorities coordinate and monitor breast cancer screening programs.