Feasibility study comparing synthesized mammography with digital breast tomosynthesis and digital mammography for simulated first round screening in a single BreastScreen NSW centre.

INTRODUCTION: While digital breast tomosynthesis (DBT) has proven to enhance cancer detection and reduce recall rates (RR), its integration into BreastScreen Australia for screening has been limited, in part due to perceived cost implications. This study aims to assess the cost effectiveness of digital mammography (DM) compared with synthesized mammography and DBT (SM + DBT) in a first round screening context for short-term outcomes. METHODS: Clients recalled for nonspecific density (NSD) as a single lesion by both readers at the Northern Sydney Central Coast BreastScreen service in 2019 were included. Prior images were excluded to simulate first-round screening. Eleven radiologists read DM and synthesized mammography with DBT (SM + DBT) images 4 weeks apart. Recall rates (RR), reading time, and diagnostic parameters were measured, and costs for screen reading and assessment were calculated. RESULT: Among 65 clients studied, 13 were diagnosed with cancer, with concordant cancer recalls. SM + DBT reduced recall rates (RR), increased reading time, maintained cancer detection sensitivity, and significantly improved other diagnostic parameters, particularly false positive rates. Benign biopsy recalls remained equivalent. While SM + DBT screen reading cost was significantly higher than DM (DM AU$890 ± 186 vs SM + DBT AU$1279 ± 265; P < 0.001), the assessment cost (DM AU$29,504 ± 9427 vs SM + DBT AU$18,021 ± 5606; P < 0.001), and combined screen reading and assessment costs were significantly lower (DM AU$30,394 ± 9508 vs SM + DBT AU$19,300 ± 5721; P = 0.001). SM + DBT screen reading and assessment of 65 patients resulted in noteworthy cost savings (AU$11,094), equivalent to assessing 12 additional clients. CONCLUSION: In first round screening, DBT yields significant cost savings by effectively reducing unnecessary recalls to assessment while maintaining diagnostic efficacy.

Radio-isotope occult lesion localization (ROLL) techniques to identify the clipped node for targeted axillary dissection (TAD) in breast cancer.

BACKGROUND: Breast cancer patients having neoadjuvant systemic therapy (NAST) who have a positive (clipped) lymph node (CN) at presentation must have that CN removed to assess pathologic response at later surgery. Multiple techniques for localizing the CN have been described. We describe a novel ROLL-based approach. METHODS: Consecutive patients between 2018 and 2021, having NAST with biopsy proven positive lymph node(s), had a clip placed into the most abnormal node(s). At later surgery sentinel node and occult lesion localization (SNOLL) was performed with peritumoral radio-isotope (99m Tc-Nanoscan) injected under ultrasound guidance. Planar and single photon emission computed tomography (SPECT-CT) images were used to identify sentinel nodes (SN) and the CN. If the CN was not a SN, then additional 99m Tc-Nanoscan was injected directly into the CN using ultrasound (ROLL). TAD was performed using a gamma probe and intra-operative specimen radiographs to confirm excision of the CN. RESULTS: Thirty-eight patients underwent TAD. 20/38 CNs were SNs on SPECT-CT. 17/38 CN were localized separately. 1/38 CN was not a SN and could not be identified on ultrasound. The remaining 37/38 (97.4%) of the CNs were removed intra-operatively. Pathological complete response in the axilla was identified in 18/38 cases. The CN was the only positive node in 10/20 cases. In 18/20 cases the CN contained the largest tumour deposit. CONCLUSION: Combining SNOLL and ROLL techniques to identify the SNs and, if separate, the CN for TAD is very reliable and logistically robust, especially for units already performing peritumoral lymphoscintigraphy.

Impact of selective use of breast MRI on surgical decision-making in women with newly diagnosed operable breast cancer.

BACKGROUND: This study evaluated the impact of breast MRI on surgical planning in selected cases of breast malignancy (invasive cancer or DCIS). MRI was used when there was ambiguity on clinical and/or conventional imaging assessment. METHODS: Consecutive women with breast malignancy undergoing breast MRI were included. Clinical, mammogram and ultrasound findings and surgical plan before and after MRI were recorded. MRI findings and histopathology results were documented and the impact of MRI on treatment planning was evaluated. RESULTS: MRI was performed in 181/1416 (12.8%) cases (invasive cancer 155/1219 (12.7%), DCIS 26/197 (13.2%)). Indications for MRI were: clinically dense breast tissue difficult to assess (n = 66; 36.5%), discordant clinical/conventional imaging assessment (n = 61; 33.7%), invasive lobular carcinoma in clinically dense breast tissue (n = 22; 12.2%), palpable/mass-forming DCIS (n = 11; 6.1%); other (n = 19; 10.5%). The recall rate for assessment of additional lesions was 35% (63/181). Additional biopsy-proven malignancy was found in 11/29 (37.9%) ipsilateral breast recalls and 8/34 (23.5%) contralateral breast recalls. MRI detected contralateral malignancy (unsuspected on conventional imaging) in 5/179 (2.8%). The additional information from MRI changed management in 69/181 (38.1%), with more unilateral surgery (wider excision or mastectomy) in 53/181 (29.3%), change to bilateral surgery in 12/181 (6.6%), less surgery in 4/181 (2.2%). Clinical examination estimated histological size within 20 mm in 57%, conventional imaging in 55% and MRI in 71%. CONCLUSION: MRI was most likely to show concordance with histopathology in the 'discordant assessment' and 'invasive lobular' groups and less likely for 'challenging clinically dense breast tissue.' MRI changed management in 69/181 (38.1%).

The influence of knowledge of mammography findings on the accuracy of breast ultrasound in symptomatic women.

Breast ultrasound is generally interpreted with knowledge of the mammographic examination. This study examined the influence of knowledge of mammography findings on the accuracy of ultrasound in women with breast symptoms. Subjects were sampled from all women 25-55 years of age consecutively attending a breast clinic. This included all 240 women shown to have breast cancer and 240 age-matched women shown not to have cancer. Ultrasound films were prospectively reviewed and reported by two radiologists independent of each other and in a blinded manner. A two-phase design was used. In the first phase, the radiologists provided an opinion on the ultrasound films. In the second phase, the ultrasound films were reread with consideration of the corresponding mammographic examination. The accuracy of reading the ultrasound with and without knowledge of the findings on mammography was compared using sensitivity and specificity, and receiver operating characteristics (ROC) curves. Reporting the ultrasound with knowledge of mammography (compared to without mammography) improved sensitivity and reduced specificity for both radiologists. For one reader, sensitivity increased from 77.5% to 86.7% (p = 0.0002) and specificity decreased from 89.7% to 85.4% (p = 0.04). For the other reader, sensitivity increased from 81.3% to 87.5% (p = 0.0023) and specificity decreased from 87.1% to 85.0% (p = 0.27). ROC curves for both radiologists showed that reporting ultrasound with knowledge of mammography resulted in small (about 3%), but significant improvement in the area under the ROC curve. Our study indicates that knowledge of the findings of mammography improves the interpretation of breast ultrasound in symptomatic women.

The influence of clinical information on the accuracy of diagnostic mammography.

OBJECTIVE: This study examined the influence of knowledge of clinical information on the accuracy of mammography in women referred for investigation of breast symptoms. METHODS: Subjects were sampled from all women consecutively attending a symptomatic breast clinic and aged 25-55 years. This included all 240 women shown to have breast cancer and 240 age-matched women shown not to have cancer. Mammography films were prospectively reported by two radiologists independently of each other in a blinded manner and without knowledge of any clinical information. The films were then re-read with information about the type and site of symptoms (and without knowledge of the level of suspicion of cancer on clinical examination). The accuracy of reading with and without information on symptoms was compared using sensitivity and specificity and receiver operating characteristic (ROC) curves. The effect of age on changes in test accuracy was examined. RESULTS: Reporting the mammogram with knowledge of clinical information (compared to without any information) significantly improved sensitivity (75.8 vs. 71.3%, P = 0.003) for one radiologist, with a non-significant reduction in specificity (85.4 vs. 87.1%, P = 0.22). For the other radiologist, it resulted in non-significant improvement in both sensitivity (75.4 vs. 73.8%, P = 0.13) and specificity (89.2 vs. 87.9%, P = 0.25). Age did not have a statistically significant effect on changes in test accuracy in our data. ROC curves for both radiologists showed that reporting mammography with knowledge of clinical information resulted in small (about 2%) but significant improvement in overall test accuracy. CONCLUSION: Our findings support the provision of clinical information relating to patients' presentation to radiologists reporting diagnostic mammography.

Sydney Breast Imaging Accuracy Study: Comparative sensitivity and specificity of mammography and sonography in young women with symptoms.

OBJECTIVE: We examined the age-specific sensitivity and specificity of mammography and sonography in symptomatic women to determine the age below which sonography may be the more accurate imaging test, which may guide the choice of initial breast imaging examination based on the woman's age. MATERIALS AND METHODS: Four hundred eighty subjects were sampled from all women consecutively attending a symptomatic breast clinic between 1994 and 1996 and ranging in age from 25 to 55 years. We included all 240 women shown to have breast cancer (thus avoiding selection bias) and 240 age-matched women shown not to have cancer. Mammograms and sonograms were prospectively interpreted independently and without knowledge of age by two radiologists in a blinded manner, with a third radiologist arbitrating disagreements. Sensitivity and specificity of each imaging test in relation to age were examined using logistic regression modeling, and accuracy was compared using the chi-square test for paired proportions. RESULTS: Sensitivity and specificity of each test were not linearly associated with age; however, the sensitivity of mammography increased substantially in women older than 50 years. Sonographic sensitivity of 81.7% was not significantly greater than mammographic sensitivity of 75.8% (chi(2)(1) = 2.06, p = 0.15). However, in women 45 years old or younger, the sensitivity of sonography was 13.2% (95% confidence interval, 2.1-24.3%) greater than that of mammography. The specificity of both tests was approximately 88.0%. CONCLUSION: These data show that sonography is the more accurate imaging test in women 45 years old or younger who present with breast symptoms and may be an appropriate initial imaging examination.