Digital Mammography Has Persistently Increased High-Grade and Overall DCIS Detection Without Altering Upgrade Rate.

OBJECTIVE. The purpose of this article is to evaluate whether digital mammography (DM) is associated with persistent increased detection of ductal carcinoma in situ (DCIS) or has altered the upgrade rate of DCIS to invasive cancer. MATERIALS AND METHODS. An institutional review board-approved retrospective search identified DCIS diagnosed in women with mammographic calcifications between 2001 and 2014. Ipsilateral cancer within 2 years, masses, papillary DCIS, and patients with outside imaging were excluded, yielding 484 cases. Medical records were reviewed for mammographic calcifications, technique, and pathologic diagnosis. Mammograms were interpreted by radiologists certified by the Mammography Quality Standards Act. The institution transitioned from film-screen mammography (FSM) to exclusive DM by 2010. Statistical analyses were performed using chi-square test. RESULTS. Of 484 DCIS cases, 158 (33%) were detected by FSM and 326 (67%) were detected by DM. The detection rate was higher with DM than FSM (1.4 and 0.7 per 1000, respectively; p < .001). The detection rate of high-grade DCIS doubled with DM compared with FSM (0.8 and 0.4 per 1000, respectively; p < .001). The prevalent peak of DM-detected DCIS was 2.7 per 1000 in 2008. Incident DM detection remained double FSM (1.4 vs 0.7 per 1000). Similar proportions of high-grade versus low- to intermediate-grade DCIS were detected with both modalities. There was no significant difference in the upgrade rate of DCIS to invasive cancer between DM (10%; 34/326) and FSM (10%; 15/158) (p = .74). High-grade DCIS led to 71% (35/49) of the upgrades to invasive cancer. CONCLUSION. DM was associated with a significant doubling in DCIS and high-grade DCIS detection, which persisted after prevalent peak. The majority of upgrades to invasive cancer arose from high-grade DCIS. DM was not associated with decreased upgrade to invasive cancer.

Digital Breast Tomosynthesis Slab Thickness: Impact on Reader Performance and Interpretation Time.

Background Digital breast tomosynthesis (DBT) helps reduce recall rates and improve cancer detection compared with two-dimensional (2D) mammography but has a longer interpretation time. Purpose To evaluate the effect of DBT slab thickness and overlap on reader performance and interpretation time in the absence of 1-mm slices. Materials and Methods In this retrospective HIPAA-compliant multireader study of DBT examinations performed between August 2013 and July 2017, four fellowship-trained breast imaging radiologists blinded to final histologic findings interpreted DBT examinations by using a standard protocol (10-mm slabs with 5-mm overlap, 1-mm slices, synthetic 2D mammogram) and an experimental protocol (6-mm slabs with 3-mm overlap, synthetic 2D mammogram) with a crossover design. Among the 122 DBT examinations, 74 mammographic findings had final histologic findings, including 31 masses (26 malignant), 20 groups of calcifications (12 malignant), 18 architectural distortions (15 malignant), and five asymmetries (two malignant). Durations of reader interpretations were recorded. Comparisons were made by using receiver operating characteristic curves for diagnostic performance and paired t tests for continuous variables. Results Among 122 women, mean age was 58.6 years ± 10.1 (standard deviation). For detection of malignancy, areas under the receiver operating characteristic curves were similar between protocols (range, 0.83-0.94 vs 0.84-0.92; P ≥ .63). Mean DBT interpretation time was shorter with the experimental protocol for three of four readers (reader 1, 5.6 minutes ± 1.7 vs 4.7 minutes ± 1.4 [P < .001]; reader 2, 2.8 minutes ± 1.1 vs 2.3 minutes ± 1.0 [P = .001]; reader 3, 3.6 minutes ± 1.4 vs 3.3 minutes ± 1.3 [P = .17]; reader 4, 4.3 minutes ± 1.0 vs 3.8 minutes ± 1.1 [P ≤ .001]), with 72% reduction in both mean number of images and mean file size (P < .001 for both). Conclusion A digital breast tomosynthesis reconstruction protocol that uses 6-mm slabs with 3-mm overlap, without 1-mm slices, had similar diagnostic performance compared with the standard protocol and led to a reduced interpretation time for three of four readers. © RSNA, 2020 See also the editorial by Chang in this issue.

Availability of prior mammograms affects incomplete report rates in mobile screening mammography.

PURPOSE: Mobile mammography can improve access to screening mammography in rural areas and underserved populations. We evaluated the frequency of incomplete reports in mobile mammography screening and the relationships between prior mammograms and recall rates. METHODS: The frequency of incomplete mammogram reports, the subgroups of those needing prior comparison mammograms, recalls for additional imaging, and availability of prior mammograms of a mobile screening mammography unit were compared with fixed site mammography from January 1, 2007 through December 31, 2009. All mobile unit mammograms were full field digital mammography (FFDM). Differences between rates of recall, incomplete reports, and availability of prior mammograms were calculated using the Chi-Square statistic. RESULTS: Of 2640 mobile mammography cases, 21.9% (578) reports were incomplete, versus 15.2% (7653) (p ≤ 0.001) of 50325 fixed site reports. Of incomplete cases, recall for additional imaging occurred among 8.3% (218) of mobile mammography reports versus 11.3% (5708) (p ≤ 0.001) of fixed site reports. Prior mammograms were needed among 13.6% (360) of mobile mammography versus 3.9% (1945) (p ≤ 0.001) of fixed site reports. Mobile mammography recall rate varied with availability of prior mammograms: 16.0% (54) when no prior mammograms, 7.6% (127) when prior mammograms were elsewhere but unavailable and 5.9% (37) when prior FFDM were immediately available (p ≤ 0.001). CONCLUSIONS: Incomplete reports were more frequent in mobile mammography than the fixed site. The availability of prior comparison mammograms at time of interpretation decreased the rate of incomplete mammogram reports. Recall rates were higher without prior comparison mammograms and lowest when comparison FFDM mammograms were available.

Use of Screening Mammography to Detect Occult Malignancy in Autologous Breast Reconstructions: A 15-year Experience.

Purpose To examine how often screening mammography depicts clinically occult malignancy in breast reconstruction with autologous myocutaneous flaps (AMFs). Materials and Methods Between January 1, 2000, and July 15, 2015, the authors retrospectively identified 515 women who had undergone mammography of 618 AMFs and who had at least 1 year of clinical follow-up. Of the 618 AMFs, 485 (78.5%) were performed after mastectomy for cancer and 133 (21.5%) were performed after prophylactic mastectomy. Medical records were used to determine the frequency, histopathologic characteristics, presentation, time to recurrence, and detection modality of malignancy. Cancer detection rate (CDR), sensitivity, specificity, positive predictive value, and false-positive biopsy rate were calculated. Results An average of 6.7 screening mammograms (range, 1-16) were obtained over 15.5 years. The frequency of local-regional recurrence (LRR) was 3.9% (20 of 515 women; 95% confidence interval [CI]: 2.2%, 5.6%); all LRRs were invasive, and none were detected in the breast mound after prophylactic mastectomy. Of the 20 women with LRR, 13 (65%) were screened annually before the diagnosis. Seven of those 13 women (54%) had clinically occult LRR, and mammography depicted five. Five of the six clinically evident recurrences (83%) were interval cancers. The median time between reconstruction and first recurrence was 4.4 years (range, 0.8-16.2 years). The CDR per AMF was 1.5 per 1000 screening mammograms (five of 3358; 95% CI: 0.18, 2.8) after mastectomy for cancer and 0 of 1000 examinations (0 of 805 mammograms; 95% CI: 0, 5) after prophylactic mastectomy. Sensitivity, specificity, positive predictive value, and false-positive biopsy rate were 42% (five of 12), 99.4% (4125 of 4151), 16% (five of 31), and 0.6% (26 of 4151), respectively. Conclusion The CDR of screening mammography (1.5 per 1000 screening mammograms) of the AMF after mastectomy for cancer is comparable to that for one native breast of an age-matched woman. Screening mammography adds little value after prophylactic mastectomy. © RSNA, 2018.

Harms of Restrictive Risk-Based Mammographic Breast Cancer Screening.

OBJECTIVE: The objective of this study was to determine if restrictive risk-based mammographic screening could miss breast cancers that population-based screening could detect. MATERIALS AND METHODS: Through a retrospective search of records at a single institution, we identified 552 screen-detected breast cancers in 533 patients. All in situ and invasive breast cancers detected at screening between January 1, 2011, and December 31, 2014, were included. Medical records were reviewed for history, pathology, cancer size, nodal status, breast density, and mammographic findings. Mammograms were interpreted by one of 14 breast imaging radiologists with 3-30 years of experience, all of whom were certified according to the Mammography Quality Standards Act. Patient ages ranged from 36 to 88 years (mean, 61 years). The breast cancer risks evaluated were family history of breast cancer and dense breast tissue. Positive family history was defined as a first-degree relative with breast cancer. Dense breast parenchyma was either heterogeneously or extremely dense. RESULTS: Group 1 consisted of the 76.7% (409/533) of patients who had no personal history of breast cancer. Of these patients, 75.6% (309/409) had no family history of breast cancer, and 56% (229/409) had nondense breasts. Group 2 consisted of the 16.7% (89/533) of patients who were 40-49 years old. Of these patients, 79.8% (71/89) had no family history of breast cancer, and 30.3% (27/89) had nondense breasts. Ductal carcinoma in situ made up 34.6% (191/552) of the cancers; 65.4% (361/552) were invasive. The median size of the invasive cancers was 11 mm. Of the screen-detected breast cancers, 63.8% (352/552) were minimal cancers. CONCLUSION: Many screen-detected breast cancers occurred in women without dense tissue or a family history of breast cancer. Exclusive use of restrictive risk-based screening could result in delayed cancer detection for many women.

Surgical biopsy is still necessary for BI-RADS 4 calcifications found on digital mammography that are technically too faint for stereotactic core biopsy.

The purpose of this study was to evaluate the outcome of faint BI-RADS 4 calcifications detected with digital mammography that were not amenable to stereotactic core biopsy due to suboptimal visualization. Following Institutional Review Board approval, a HIPAA compliant retrospective search identified 665 wire-localized surgical excisions of calcifications in 606 patients between 2007 and 2010. We included all patients that had surgical excision for initial diagnostic biopsy due to poor calcification visualization, whose current imaging was entirely digital and performed at our institution and who did not have a diagnosis of breast cancer within the prior 2 years. The final study population consisted of 20 wire-localized surgical biopsies in 19 patients performed instead of stereotactic core biopsy due to poor visibility of faint calcifications. Of the 20 biopsies, 4 (20% confidence intervals 2, 38%) were malignant, 5 (25%) showed atypia and 11 (55%) were benign. Of the malignant cases, two were invasive ductal carcinoma (2 and 1.5 mm), one was intermediate grade DCIS and one was low-grade DCIS. Malignant calcifications ranged from 3 to 12 mm. The breast density was scattered in 6/19 (32%), heterogeneously dense in 11/19 (58%) and extremely dense in 2/19 (10%). Digital mammography-detected faint calcifications that were not amenable to stereotactic biopsy due to suboptimal visualization had a risk of malignancy of 20%. While infrequent, these calcifications should continue to be considered suspicious and surgical biopsy recommended.

Adherence to screening mammography among American Indian women of the Northern Plains.

Breast cancer is a burden for American Indian (AI) women who have younger age at diagnosis and higher stage of disease. Rural areas also have had less access to screening mammography. An Indian Health Service Mobile Women's Health Unit (MWHU) was implemented to improve mammogram screening of AI women in the Northern Plains. Our purpose was to determine the past adherence to screening mammography at a woman's first presentation to the MWHU for mammogram screening. Date of the most recent prior non-MWHU mammogram was obtained from mammography records. Adherence to screening guidelines was defined as the prior mammogram occurring 1-2 years before the first MWHU visit among women >41 years, and was the main outcome, whereas, age and clinic site were predictors. Adherence was compared with national data of the Breast Cancer Surveillance Consortium (BCSC). Among 1,771 women >41 years, adherence to screening mammography guidelines was 48.01 % among >65 years, 42.05 % among 50-64 years, 33.43 % among 41-49 years, and varied with clinic site (25.23-65.93 %). Age (p < 0.0001) and clinic site (p < 0.0001) were associated with adherence. Overall, adherence to screening mammography guidelines was found in 39.86 % (706/1771) of MWHU women versus 74.34 % (747,095/1,004,943) of BCSC women. The majority (60.14 %) of women at first presentation to the MWHU had not had mammograms in the previous 2 years, lower screening adherence than nationally (25.66 %). Adherence was lowest among women ages 41-49, and varied with clinic site. Findings suggest disparities in mammography screening among these women.

The Breast Radiologist as a Public Educator: Designing an Effective Presentation for a Lay Audience.

Educating the public about breast cancer screening and diagnosis is important. Medical and regulatory agencies encourage shared decision making about undergoing breast cancer screening, and there are many places women can get information and misinformation. The Internet and other media sources present information that may not be correct or understandable. Breast radiologists are uniquely qualified to provide women with the accurate information necessary to enable informed choices. As a specialty, we have an obligation to our community to provide relevant and understandable information. We can accomplish that through community outreach forums. Presentations should be understandable with plain language, focusing on our key message and using pertinent images or icons. Slides should be simple and avoid medical jargon or complex statistics. As we engage with the community, we provide a vital service to the health of our community and foster respect of our specialty.

Costs of achieving high patient compliance after recall from screening mammography.

OBJECTIVE: The purpose of our study was to document the hidden costs in achieving high recall patient compliance from an off-site screening mammography program. MATERIALS AND METHODS: This study was approved by our institutional review board. At our institution, no patient was placed in final BI-RADS assessment category 3, 4, or 5 without a diagnostic study. Each incomplete study, in addition to the formal report, was flagged on the day sheet, letters were sent to the referring physician and patient, and an incomplete computer code was added. Working from the day sheets, a clerk contacted the patient by telephone within 2 working days to schedule the diagnostic study. Diagnostic slots were purposely left open to accommodate these cases. An ongoing computer tickler file of incomplete codes provided a further check. A time study of clerical performance with recalled patients was measured prospectively for 100 consecutive cases. RESULTS: For the years 2002-2004, 4,025 (13%) of 30,286 screening patients were recalled for diagnostic mammography. After an average of 2.2 telephone calls per patient, (3.64 minutes of clerical time), 3,977 of 4,005 patients returned for a diagnostic study. Forty-eight of 4,025 initially noncompliant patients received an average of six telephone calls (4.7 minutes) and a registered letter. One of the 28 initially noncompliant patients went on to biopsy that revealed a breast cancer. Patient compliance was 4,005 (99.5%) of 4,025. The additional cost for this program was $4,724 divided by 30,286 screening patients, or 16 cents per screening patient. CONCLUSION: The radiology department assumed responsibility for contacting patients who needed recall for additional diagnostic imaging. Using strict documentation of the incomplete breast imaging evaluations, computer checks, clerical support, and prompt scheduling, we achieved 99.5% compliance. The additional cost was small, 16 cents per screening patient.

Ensuring excision of intraductal lesions: marker placement at time of ductography.

RATIONALE AND OBJECTIVES: To propose grid coordinate marker placement for patients with suspicious ductogram findings occult on routine workup. To compare the success of marker placement and wire localization (WL) with ductogram-guided WL. MATERIALS AND METHODS: A retrospective search of radiology records identified all patients referred for ductography between January 2001 and May 2008. Results for 16 patients referred for ductogram-guided WL and 5 patients with grid coordinate marker placement at the time of ductography and subsequent WL were reviewed. Surgical pathology results and clinical follow-up were reviewed for concordance. RESULTS: Nine of 16 patients (56.3%) underwent successful ductogram-guided WL. Eight of nine patients had papillomas, one of which also had atypical ductal hyperplasia (ADH). One of nine patients had ectatic ducts with inspisated debris. Seven patients who failed ductogram-guided WL eventually underwent open surgical biopsy. Four of seven patients had papillomas, one of which also had lobular carcinoma in situ. Remaining patients had ADH (1/7) and fibrocystic changes with chronic inflammation (3/7). All five (100%) patients with grid coordinate marker placement underwent successful WL and marker excision. Pathology results included three papillomas, papillary intraductal hyperplasia, and fibrocystic change. CONCLUSION: Grid coordinate marker placement at the time of abnormal ductogram provided an accurate method of localizing ductal abnormalities that are occult on routine workup, thus facilitating future WL. Marker placement obviated the need for repeat ductogram on the day of surgery and ensured surgical removal of the ductogram abnormality.