Breast Density and Risk of Interval Cancers: The Effect of Annual Versus Biennial Screening Mammography Policies in Canada

Regular screening mammography reduces breast cancer mortality. However, in women with dense breasts, the performance of screening mammography is reduced, which is reflected in higher interval cancer rates (ICR). In Canada, population-based screening mammography programs generally screen women biennially; however, some provinces and territories offer annual mammography for women with dense breast tissue routinely and/or on recommendation of the radiologist. This study compared the ICRs in those breast screening programs with a policy of annual vs. those with biennial screening for women with dense breasts. Among 148,575 women with dense breasts screened between 2008 to 2010, there were 288 invasive interval breast cancers; screening programs with policies offering annual screening for women with dense breasts had fewer interval cancers 63/70,814 (ICR 0.89/1000, 95% CI: 0.67-1.11) compared with those with policies of usual biennial screening 225/77,761 (ICR 1.45 /1000 (annualized), 95% CI: 1.19-1.72) i.e. 63% higher (p = 0.0016). In screening programs where radiologists' screening recommendations were able to be analyzed, a total of 76,103 women were screened, with 87 interval cancers; the ICR was lower for recommended annual (65/69,650, ICR 0.93/1000, 95% CI: 0.71, 1.16) versus recommended biennial screening (22/6,453, ICR 1.70/1000 (annualized), 95%CI: 0.70, 2.71)(p = 0.0605). Screening program policies of annual as compared with biennial screening in women with dense breasts had the greatest impact on reducing interval cancer rates. We review our results in the context of current dense breast notification in Canada.

Screening for breast cancer in 2018-what should we be doing today?

Although screening mammography has delivered many benefits since its introduction in Canada in 1988, questions about perceived harms warrant an up-to-date review. To help oncologists and physicians provide optimal patient recommendations, the literature was reviewed to find the latest guidelines for screening mammography, including benefits and perceived harms of overdiagnosis, false positives, false negatives, and technologic advances. For women 40-74 years of age who actually participate in screening every 1-2 years, breast cancer mortality is reduced by 40%. With appropriate corrections, overdiagnosis accounts for 10% or fewer breast cancers. False positives occur in about 10% of screened women, 80% of which are resolved with additional imaging, and 10%, with breast biopsy. An important limitation of screening is the false negatives (15%-20%). The technologic advances of digital breast tomosynthesis, breast ultrasonography, and magnetic resonance imaging counter the false negatives of screening mammography, particularly in women with dense breast tissue.

Underestimation of malignancy in biopsy-proven cases of stromal fibrosis

OBJECTIVE

To determine the rate of underestimation of malignancy in patients with biopsy-proven stromal fibrosis.

METHODS

Following institutional review board approval, we retrospectively reviewed the charts of patients with biopsy-proven stromal fibrosis who underwent percutaneous breast biopsy in the 5-year period between 1 January 2005 and 31 December 2009. The medical records and the histopathology in patients who underwent repeat biopsy and/or surgical excision at the site of stromal fibrosis within 2 years were reviewed. Interval stability for up to 2 years was documented in patients who did not undergo additional biopsy or surgical excision. An upgrade was defined as any patient with biopsy-proven stromal fibrosis or fibroadenoma with evidence of malignancy at the site of biopsy within 2 years.

RESULTS

365 cases of stromal fibrosis were identified, of which 25 (7%) were upgraded to in situ or invasive malignancy on repeat biopsy or surgical excision. 7 were upgraded to ductal carcinoma in situ and 18 were upgraded to invasive cancer. Of the upgraded cases, 8 out of 24 (32%) were considered concordant with a benign diagnosis. The false-negative rate, that is, cases of stromal fibrosis concordant with benignity, but with subsequent upgrade, comprised 2% of all cases.

CONCLUSION

In biopsy-proven cases of stromal fibrosis, there is a 7% upgrade to malignancy. We recommend that all instances of stromal fibrosis with radiology-pathology discordance undergo repeat biopsy or surgical excision. Cases that demonstrate radiology-pathology concordance can be safely categorized as a Breast Imaging Reporting and Data System 3 (BI-RADS® 3) lesion with a 6-month follow-up, owing to a false-negative rate for missed cancer of 2%.

ADVANCES IN KNOWLEDGE

We now recommend that concordant cases of stromal fibrosis be categorized as BI-RADS 3 with a short-term follow-up, as this results in a missed cancer rate of 2%.

The radiological spectrum of pulmonary lymphoproliferative disease

Pulmonary lymphoproliferative disorders (LPD) are characterised by abnormal proliferation of indigenous cell lines or infiltration of lung parenchyma by lymphoid cells. They encompass a wide spectrum of focal or diffuse abnormalities, which may be classified as reactive or neoplastic on the basis of cellular morphology and clonality. The spectrum of reactive disorders results primarily from antigenic stimulation of bronchial mucosa-associated lymphoid tissue (MALT) and comprises three main entities: follicular bronchiolitis, lymphoid interstitial pneumonia and (more rarely) nodular lymphoid hyperplasia. Primary parenchymal neoplasms are most commonly extranodal marginal zone lymphomas of MALT origin (MALT lymphomas), followed by diffuse large B-cell lymphomas (DLBCLs) and lymphomatoid granulomatosis (LYG). Secondary lymphomatous parenchymal neoplasms (both Hodgkin and non-Hodgkin lymphomas) are far more prevalent than primary neoplasms. Acquired immune deficiency syndrome (AIDS)-related lymphoma (ARL) and post-transplantation lymphoproliferative disorder (PTLD) may also primarily affect the lung parenchyma. Modern advances in treatments for AIDS and transplant medicine are associated with an increase in the incidence of LPD and have heightened the need to understand the range of imaging appearance of these diseases. The multidetector CT (MDCT) findings of LPD are heterogeneous, thereby reflecting the wide spectrum of clinical manifestations of these entities. Understanding the spectrum of LPD and the various imaging manifestations is crucial because the radiologist is often the first one to suggest the diagnosis and has a pivotal role in differentiating these diseases. The current concepts of LPD are discussed together with a demonstration of the breadth of MDCT patterns within this disease spectrum.

Systemic arterial air embolism after percutaneous lung biopsy

Systemic arterial air embolism is a rarely encountered but much feared complication of percutaneous lung biopsy. We present a comprehensive review of iatrogenic air embolism post-lung biopsy, a complication that is often suboptimally managed. This review was inspired by our own institutional experience and we use this to demonstrate that excellent outcomes from this complication can be seen with prompt treatment using hyperbaric oxygen chamber therapy, after initial patient stabilization has been achieved. Pathophysiology, clinical features, and risk factors are reviewed and misconceptions regards venous versus arterial air embolism are examined. An algorithm is provided for radiologists to ensure suspected patients are appropriately managed with more favourable outcomes.

Breast MRI in the evaluation of locally recurrent or new breast cancer in the postoperative patient: correlation of morphology and enhancement features with the BI-RADS category

BACKGROUND

While breast magnetic resonance imaging (MRI) is a highly sensitive test for detecting breast carcinoma, its specificity is lower, and several methods have been described on how to optimize specificity.

PURPOSE

To compare the specificity and sensitivity of the BI-RADS category with the Fischer score in breast MRI for diagnosing cancer in women previously treated for breast cancer.

MATERIAL AND METHODS

Women referred for evaluation of possible local recurrence or new breast cancer underwent breast MRI examination. Morphologic and kinetic enhancement characteristics were evaluated. BI-RADS category and Fischer score were assigned for each enhancing lesion and compared using a chi-square test. Sensitivity, specificity,and positive predictive values for 27 morphologic and enhancement characteristics were calculated. Pathologic diagnosis was obtained in all patients with enhancing lesions who had ultrasound or mammographic correlation. In those without correlate, 6-, 12-, and 24-month follow-up breast MRIs were obtained. Interobserver kappa correlation was determined for each variable studied.

RESULTS

34 benign and 32 malignant lesions were identified in 26 of 30 patients. BIRADS category yielded a specificity of 77.1% and a sensitivity of 81.8%. Fischer score had a lower specificity and sensitivity (62.9% and 72.7%, respectively) (P<0.0001). Of the 27 variables studied, >100% enhancement was more sensitive than BI-RADS for malignant lesions. Specificity was highest for rim enhancement (97.1%), but sensitivity was low (24.2%). Interobserver kappa correlation was good for all 27 characteristics(k=0.84), and highest for BI-RADS assessment (k=0.91).

CONCLUSION

BI-RADS category in breast MRI had the highest combination of specificity and sensitivity, and the highest interobserver correlation. Fischer score and other morphologic and enhancement features lack sensitivity or specificity and do not have high positive predictive values when analyzed as single independent variables.

In situ central pulmonary artery thrombosis in primary pulmonary hypertension

A rare case of extensive in situ central pulmonary artery thrombosis in primary pulmonary hypertension (PPH) is presented. The differentiation from chronic thromboembolic pulmonary arterial hypertension (CTEPH) is of paramount importance because of different therapeutic strategies. In this case, the presence of mural thrombus in the central pulmonary arteries on computed tomography made the distinction difficult. However, the possibility of in situ thrombosis was suggested on the basis of absence of other findings of CTEPH (abrupt narrowing/truncation of segmental arteries, variation in size of segmental vessels, arterial webs, mosaic attenuation, pulmonary infarcts, and dilated bronchial arteries), and this was confirmed on final pathology.

Computed tomography demonstration of systemic arterial supply to lung without sequestration

We present two cases of systemic arterial supply to lung without sequestration diagnosed confidently based on imaging findings on computed tomography scan, thereby obviating the need for invasive diagnostic procedures.

Oropharyngeal airway diameter during sedation in children with and without developmental delay

STUDY OBJECTIVE

To determine whether children with developmental delay would have closer apposition of upper airway tissues during sedation, perhaps because of poor coordination of upper airway musculature.

DESIGN

Case-control and retrospective chart review.

SETTING

Tertiary-care pediatric teaching hospital.

PATIENTS

40 children 3 to 6 years of age, with and without a diagnosis of developmental delay.

MEASUREMENTS

Subjects received only pentobarbital sedation by a protocol. Magnetic resonance imaging (MRI) scans of the head were reviewed, and transverse airway diameters at the soft palate and tongue were determined from midline sagittal images.

MAIN RESULTS

Age, weight, sedative dose, MRI window level, and window width were not different between patients with and without developmental delay. We found the airway diameter at the level of the soft palate was decreased 40% in children with developmental delay compared with those children without delay, 3 mm (1.4, 5.5 interquartile range) versus 5 mm (3, 8); p = 0.035, power 76%.

CONCLUSIONS

The anteroposterior oropharyngeal airway diameter was smaller in children with developmental delay than in those without developmental delay, in static MRI images. It is possible that children with developmental delay are at higher risk for airway obstruction during sedation.

Systemic sclerosis: using high-resolution CT to detect lung disease in children

OBJECTIVE

The purpose of this study was to determine the prevalence of interstitial lung disease and the severity of disease in children with systemic sclerosis using high-resolution CT (HRCT).

SUBJECTS AND METHODS

Eleven children (mean age, 11 years) with scleroderma underwent HRCT, chest radiography, and pulmonary function testing. Eight of these 11 patients also underwent follow-up HRCT. HRCT studies were assessed by two observers for ground-glass attenuation, honeycombing, and other abnormalities. Profusion scores for ground-glass attenuation and honeycombing were determined by multiplying severity of disease by the percentage of lung involvement.

RESULTS

Chest radiographs predicted interstitial lung disease in only two patients, whereas HRCT showed interstitial lung disease in eight patients (p = .05). On HRCT, ground-glass attenuation was found in eight patients (73%), honeycombing in five patients (45%), linear opacities in six patients (55%), and subpleural micronodules in seven patients (64%). By the end of the study, 10 patients (91%) had evidence of interstitial lung disease on HRCT. Overall, profusion scores for these 10 patients showed four patients with mild, one with moderate, and five with severe disease. Also, HRCT revealed worsening disease in three of eight patients. We found no correlation between duration of scleroderma and severity of interstitial lung disease (p > .02). Seven patients with evidence of lung disease on HRCT had abnormal results on pulmonary function tests; patients with the highest scores for ground-glass attenuation had the most abnormal results on pulmonary function tests (p < .01).

CONCLUSION

HRCT shows significant pulmonary disease in children with systemic sclerosis, revealing abnormalities in 91% of our patients. Pulmonary disease should be suspected in children with scleroderma, even if the chest radiograph has normal findings.

High-resolution CT of pediatric lung disease: imaging findings

The HRCT findings of diseases of the pulmonary parenchyma and airways in children are often similar to those seen in adults. However, some conditions, particularly IPF, pulmonary fibrosis associated with scleroderma, and Langerhans histiocytosis, may have different presentations and a more rapid progression in children than in adults. HRCT may be helpful for assessing patients with suspected diseases of the pulmonary parenchyma or airways, particularly when radiographic findings are normal or nonspecific.

T1 lung cancer: prevalence of mediastinal nodal metastases and diagnostic accuracy of CT

To determine the prevalence of mediastinal lymph node metastases in T1 non-small cell lung cancer and assess the sensitivity and specificity of computed tomography (CT) in detection of such metastases, the CT scans and surgical findings in 104 patients with T1 lesions were reviewed. Nodes longer than 10 mm on the short or long axis were considered abnormal. All patients underwent thorough mediastinal lymph node dissection at mediastinoscopy or thoracotomy. A total of 362 lymph nodes were sampled. Nodal metastases were present in 22 patients (21%). The sensitivity of CT for metastases to individual nodal stations was 41% for nodes measured on the short axis and 55% for those measured on the long axis. The specificity was 93% and 86%, respectively. When the adjacent nodal stations were included in the analysis, the sensitivity of CT was 59% for nodes measured on the short axis and 77% for those measured on the long axis; the specificity was 91% and 73%, respectively. T1 lung cancer has a higher prevalence of lymph node metastasis than previously reported, and CT is recommended in the preoperative staging of this disease.