Contrast-Enhanced Spectral Mammography Assessment of Patients Treated with Neoadjuvant Chemotherapy for Breast Cancer.

BACKGROUND: Evaluating the tumor response to neoadjuvant chemotherapy is key to planning further therapy of breast cancer. Our study aimed to evaluate the effectiveness of low-energy and subtraction contrast-enhanced spectral mammography (CESM) images in the detection of complete response (CR) for neoadjuvant chemotherapy (NAC) in breast cancer. METHODS: A total of 63 female patients were qualified for our retrospective analysis. Low-energy and subtraction CESM images just before the beginning of NAC and as a follow-up examination 2 weeks before the end of chemotherapy were compared with one another and assessed for compliance with the postoperative histopathological examination (HP). The response to preoperative chemotherapy was evaluated based on the RECIST 1.1 criteria (Response Evaluation Criteria in Solid Tumors). RESULTS: Low-energy images tend to overestimate residual lesions (6.28 mm) and subtraction images tend to underestimate them (2.75 mm). The sensitivity of low-energy images in forecasting CR amounted to 33.33%, while the specificity was 92.86%. In the case of subtraction CESM, the sensitivity amounted to 85.71% and the specificity to 71.42%. CONCLUSIONS: CESM is characterized by high sensitivity in the assessment of CR after NAC. The use of only morphological assessment is insufficient. CESM correlates well with the size of residual lesions on histopathological examination but tends to underestimate the dimensions.

Retrospective Comparison of Contrast-Enhanced Spectral Mammography with Digital Mammography in Assessing Tumor Size in 668 Cases of Breast Cancer.

BACKGROUND Contrast-enhanced spectral mammography (CESM) is digital mammography with contrast agent. This promising new breast imaging method can be used for planning surgical treatment. This study compared CESM versus digital mammography (MG) in evaluating tumor size in breast cancer. MATERIAL AND METHODS Comparison of tumor dimensions in CESM, MG, and histopathology was made. The correlation of these data was assessed by histopathological type, biological subtype, grading of the carcinoma, and patient age. RESULTS The average difference in tumor size between CESM and histopathological examination was 5 mm. The differences in size measurement between CESM and MG were significant (p=0.00). The Pearson's linear correlation coefficients of CESM versus HP and MG versus HP were -0.01 (p=0.79) and -0.25 (p=0.00), respectively, indicating no differences between CESM and HP based on the lesion size. A weak negative correlation between those values was observed on MG. No relationship was found between the tumor size in CESM and the biological subtype, carcinoma malignancy degree, or patient age. CONCLUSIONS CESM is a new diagnostic method in breast cancer. The accuracy of measurement of tumor size using CESM is independent of lesion size, but it overestimates the size by 5 mm on average. The difference is not dependent on grading, biological subtype of the carcinoma, or patient age. They concern the histopathological type, and values are significantly greater in pre­invasive carcinomas.