[Quality control in breast sonography]

Best Practice Guideline - DEGUM Recommendations on Breast Ultrasound

Alongside mammography, breast ultrasound is an important and well-established method in assessment of breast lesions. With the "Best Practice Guideline", the DEGUM Breast Ultrasound (in German, "Mammasonografie") working group, intends to describe the additional and optional application modalities for the diagnostic confirmation of breast findings and to express DEGUM recommendations in this Part II, in addition to the current dignity criteria and assessment categories published in Part I, in order to facilitate the differential diagnosis of ambiguous lesions.The present "Best Practice Guideline" has set itself the goal of meeting the requirements for quality assurance and ensuring quality-controlled performance of breast ultrasound. The most important aspects of quality assurance are explained in this Part II of the Best Practice Guideline.

[Modern gray-scale sonography of the breast]

Recently, the diagnosis of breast diseases by ultrasound has changed radically. It is no longer a complementary modality to mammography but a separate method to investigate breast disease. Innovative high-resolution ultrasound allows more specific diagnosis of breast tumors. Tissue-harmonic imaging not only uses the transmitted, fundamental frequency to obtain an image but also the harmonic frequency. The harmonic signal is processed by the ultrasound system with the result of better delineation of tissue structures and spatial compounding assembles an image from multiple images taken from different angles of echo waves. The effect is the reduction of artifacts with optimized contrast. Finally the advanced speckle reduction technique is used to smooth and homogenize the image. Additionally continuous advancement of new high-resolution linear transducers is responsible for the essential improvement of image quality. In conclusion, it is recommended to integrate all of the described modalities in order to obtain diagnostically conclusive image quality. This article demonstrates the new techniques and applications exemplified using images.

Early detection of breast cancer: benefits and risks of supplemental breast ultrasound in asymptomatic women with mammographically dense breast tissue. A systematic review

BACKGROUND

Mammographic screening alone will miss a certain fraction of malignancies, as evidenced by retrospective reviews of mammograms following a subsequent screening. Mammographic breast density is a marker for increased breast cancer risk and is associated with a higher risk of interval breast cancer, i.e. cancer detected between screening tests. The purpose of this review is to estimate risks and benefits of supplemental breast ultrasound in women with negative mammographic screening with dense breast tissue.

METHODS

A systematic search and review of studies involving mammography and breast ultrasound for screening of breast cancer was conducted. The search was performed for the period 1/2000-8/2008 within the data source of PubMed, DARE, and Cochrane databases. Inclusion and exclusion criteria were determined prospectively, and the Oxford evidence classification system for diagnostic studies was used for evidence level. The parameters biopsy rate, positive predictive value (PPV) for biopsy, cancer yield for breast ultrasound alone, and carcinoma detection rate by breast density were extracted or constructed.

RESULTS

The systematic search identified no randomized controlled trials or systematic reviews, six cohort studies of intermediate level of evidence (3b) were found. Only two of the studies included adequate follow-up of subjects with negative or benign findings. Supplemental breast ultrasound after negative mammographic screening permitted diagnosis of primarily invasive carcinomas in 0.32% of women in breast density type categories 2-4 of the American College of Radiology (ACR); mean tumor size for those identified was 9.9 mm, 90% with negative lymph node status. Most detected cancers occurred in mammographically dense breast ACR types 3 and 4. Biopsy rates were in the range 2.3%-4.7%, with PPV of 8.4-13.7% for those biopsied due to positive ultrasound, or about one third of the PPV of biopsies due to mammography.

LIMITATIONS

The study populations included wide age ranges, and the application to women age 50-69 years as proposed for mammographic screening could result in less striking benefit. Further validation studies should employ a uniform assessment system such as BI-RADS and report not only PPV, but also negative predictive value, sensitivity and specificity.

CONCLUSION

Supplemental breast ultrasound in the population of women with mammographically dense breast tissue (ACR 3 and 4) permits detection of small, otherwise occult, breast cancers. Potential adverse impacts for women in this intermediate risk group are associated with an increased biopsy rate.

Intra-operative sonography: a valuable aid during breast-conserving surgery for occult breast cancer

BACKGROUND

Breast cancer is increasingly detected during an early non-palpable stage. Together with pre-operative marking of the mass, intra-operative imaging provides invaluable clues. This study was designed to evaluate the usefulness of intra-operative sonography in the hands of the surgeon.

METHODS

Between July 2001 and October 2006, 567 patients underwent treatment for operable breast cancer at the landeskrankenhaus (LHK) Feldkirch. Three hundred and sixty lesions were not palpable. Two hundred and ninety-nine patients with poorly definable or non-definable lesions well seen by ultrasound imaging underwent intra-operative sonography (group 1), while 61 patients with non-palpable lesions only seen on mammography (group 2) were subjected to pre-operative needle localization. The study was non-randomized with prospective data acquisition

RESULTS

All lesions were identified by both sonography and pre-operative needle localization. In the ultrasound group (group 1) 81% of the lesions were successfully removed by primary intention without metachronous secondary surgery versus 62% in group 2 (p < 0.00228). Eighty-eight percent of the lesions in group 1 were eligible for breast-conserving surgery versus 75% in group 2. The mean clear margin in group 1 was substantially smaller (4.8 mm) than in group 2 (7.2 mm) (p < 0.0001).

CONCLUSION

Intra-operative sonography proved to be a reliable and helpful tool in the hands of the surgeon, not only for tumor localization, but also for orientation during tumor excision. It simplifies organizational work and spares the patient the discomfort of pre-operative needle localization.

Rationale for a diagnostic chain in gestational breast tumor diagnosis

Due to the physiological tissue alterations of the breast during pregnancy and lactation the diagnosis of a breast tumor by palpation, imaging and fine-needle biopsy is difficult and often unreliable. The purpose of our study was to review the value of imaging (mammography and ultrasonography) and biopsy techniques in order to work out a reliable protocol for evaluating gestational tumors. We performed a retrospective analysis of 25 patients with clinical diagnosis of gestational breast tumors during a 4-year period from 1995 to 1999. Specimens were obtained by core biopsy for histological examination. Invasive breast cancer was diagnosed in five patients, malignant lymphoma of the skin in one patient. The tumors in the remaining 19 patients proved benign. The overall accuracy was 0.91 for conventional mammography, 0.76 for conventional and panoramic ultrasound and 0.48 for color-coded sonography. Mammography as the most reliable imaging method should be used to evaluate all patients in whom ultrasonographic findings are suspicious for tumor. Radiation phobia should not prevent the performance of mammography under these circumstances. Nevertheless, all pre-operative methods of diagnosing gestational breast tumors other than core biopsy are unreliable.

Pathologic breast conditions in childhood and adolescence: evaluation by sonographic diagnosis

OBJECTIVE

The growing awareness of female breast cancer has led to increased sensitivity toward pathologic breast conditions in children and adolescents. Thus, approximately 15% of patients in child and adolescent gynecology are referred for the first time because of conspicuous features of the breast such as pain, palpable masses, and other findings on visual inspection. The aim of this study was to analyze the underlying diagnoses and diseases and determine the status of breast sonography in the diagnostic process.

METHODS

The study population consisted of 62 female patients between 8 weeks and 20 years of age (1997-2002) who were examined clinically, followed by standardized sonography (7.5-13 MHz, conventional B-mode panoramic sonography). Presumed diagnoses were confirmed by biopsy in some patients (n = 16) and by follow-up with clinical examination and sonography in most cases (n = 46).

RESULTS

The clinical and sonographic evaluation confirmed 4 main groups of diagnoses: benign tumors (15), developmental disturbances (14), cystic changes (11), and inherent defects (7). In the remaining cases, the findings were no abnormality (9), nipple discharge without evidence of pathologic or morphologic correlates (3), abscesses (2), and epidermoid cyst (1).

CONCLUSIONS

Knowledge of regular breast development and its variants is essential for the physician. Given knowledge of the sonographic appearance of physiologic breast development and specific lesions, breast sonography is most helpful in identifying and characterizing abnormalities and guiding further investigation.