Newer Technologies in Breast Cancer Imaging: Dedicated Cone-Beam Breast Computed Tomography

Abstract

Dedicated breast computed tomography (CT) is the latest in a long history of breast imaging techniques dating back to the 1960s. Breast imaging is performed both for cancer screening as well as for diagnostic evaluation of symptomatic patients. Dedicated breast CT received US Food and Drug Administration approval for diagnostic use in 2015 and is slowly gaining recognition for its value in diagnostic 3-dimensional imaging of the breast, and also for injected contrast-enhanced imaging applications. Conventional mammography has known limitations in sensitivity and specificity, especially in dense breasts. Breast tomosynthesis was US Food and Drug Administration approved in 2011 and is now widely used. Dedicated breast CT is the next technological advance, combining real 3-dimensional imaging with the ease of contrast administration. The lack of painful compression and manipulation of the breasts also makes dedicated breast CT much more acceptable for the patients.

Fig. 1. Ductal Carcinoma In-situ

64 year-old woman presents for screening mammogram. Mammographic CC (A) and MLO (B) views demonstrate grouping of pleomorphic calcifications in the left breast at the 12 o’clock position (arrows). Reformatted non-enhanced CBCT images at 0.273 mm standard resolution (C) and 0.122 mm high-resolution (D) clearly depict grouping of calcifications; morphology of calcifications are more clearly depicted in the higher resolution images. Lesion diagnosed as DCIS at time of biopsy.

Fig. 1. Ductal Carcinoma In-situ

64 year-old woman presents for screening mammogram. Mammographic CC (A) and MLO (B) views demonstrate grouping of pleomorphic calcifications in the left breast at the 12 o’clock position (arrows). Reformatted non-enhanced CBCT images at 0.273 mm standard resolution (C) and 0.122 mm high-resolution (D) clearly depict grouping of calcifications; morphology of calcifications are more clearly depicted in the higher resolution images. Lesion diagnosed as DCIS at time of biopsy.

Fig. 1. Ductal Carcinoma In-situ

64 year-old woman presents for screening mammogram. Mammographic CC (A) and MLO (B) views demonstrate grouping of pleomorphic calcifications in the left breast at the 12 o’clock position (arrows). Reformatted non-enhanced CBCT images at 0.273 mm standard resolution (C) and 0.122 mm high-resolution (D) clearly depict grouping of calcifications; morphology of calcifications are more clearly depicted in the higher resolution images. Lesion diagnosed as DCIS at time of biopsy.

Fig. 1. Ductal Carcinoma In-situ

64 year-old woman presents for screening mammogram. Mammographic CC (A) and MLO (B) views demonstrate grouping of pleomorphic calcifications in the left breast at the 12 o’clock position (arrows). Reformatted non-enhanced CBCT images at 0.273 mm standard resolution (C) and 0.122 mm high-resolution (D) clearly depict grouping of calcifications; morphology of calcifications are more clearly depicted in the higher resolution images. Lesion diagnosed as DCIS at time of biopsy.

Fig. 2. Small Invasive Ductal Carcinoma

55 year-old woman presents for screening mammogram. Mammographic CC (A) and MLO (B) views demonstrate heterogeneously dense breast tissue with ill-defined focal asymmetry in the deep right breast at the 12 o’clock position (white circles). Contrast enhanced CBCT demonstrates more clearly a subcentimeter irregular mass (crosshairs) at the 12 o’clock location (C). Lesion diagnosed as invasive ductal carcinoma at time of biopsy.

Fig. 2. Small Invasive Ductal Carcinoma

55 year-old woman presents for screening mammogram. Mammographic CC (A) and MLO (B) views demonstrate heterogeneously dense breast tissue with ill-defined focal asymmetry in the deep right breast at the 12 o’clock position (white circles). Contrast enhanced CBCT demonstrates more clearly a subcentimeter irregular mass (crosshairs) at the 12 o’clock location (C). Lesion diagnosed as invasive ductal carcinoma at time of biopsy.

Fig. 2. Small Invasive Ductal Carcinoma

55 year-old woman presents for screening mammogram. Mammographic CC (A) and MLO (B) views demonstrate heterogeneously dense breast tissue with ill-defined focal asymmetry in the deep right breast at the 12 o’clock position (white circles). Contrast enhanced CBCT demonstrates more clearly a subcentimeter irregular mass (crosshairs) at the 12 o’clock location (C). Lesion diagnosed as invasive ductal carcinoma at time of biopsy.

Fig. 3. Assessment of index lesion and extent of disease

Patient presents with palpable mass in the right breast. Mammographic CC (A) and MLO (B) views demonstrate large irregular mass at the 12 o’clock position consistent with BIRADS-5:highly suspicious (white arrows). (c) Contrast enhanced CBCT was performed to evaluate extent of disease, which demonstrates the index lesion in exquisite detail (crosshairs). No satellite lesions or axillary adenopathy is identified.

Fig. 3. Assessment of index lesion and extent of disease

Patient presents with palpable mass in the right breast. Mammographic CC (A) and MLO (B) views demonstrate large irregular mass at the 12 o’clock position consistent with BIRADS-5:highly suspicious (white arrows). (c) Contrast enhanced CBCT was performed to evaluate extent of disease, which demonstrates the index lesion in exquisite detail (crosshairs). No satellite lesions or axillary adenopathy is identified.

Fig. 3. Assessment of index lesion and extent of disease

Patient presents with palpable mass in the right breast. Mammographic CC (A) and MLO (B) views demonstrate large irregular mass at the 12 o’clock position consistent with BIRADS-5:highly suspicious (white arrows). (c) Contrast enhanced CBCT was performed to evaluate extent of disease, which demonstrates the index lesion in exquisite detail (crosshairs). No satellite lesions or axillary adenopathy is identified.

Fig. 4. Benign lesion and potential for BI-RADS downgrade

51 year-old woman presents with palpable lump in the left breast and refused conventional work-up using compression mammography because of discomfort. Following initial evaluation with ultrasound and ultrasound-guided biopsy results consistent with benign fibroadenoma, the patient presented for post-clip imaging using CBCT as a more comfortable alternative to compression mammography. Nonenhanced CBCT clearly demonstrates benign features and biopsy clip in place (crosshairs). Notably, this lesion would been initially categorized as BIRADS-3:probably benign by CBCT appearance, with a recommendation for short interval follow-up imaging – clearly a preferable alternative to ultrasound-guided biopsy in a patient concerned about breast discomfort.

Fig. 5. Evaluation of response to therapy

66 year-old woman presents with palpable lump in the left breast. Mammographic CC (A)and MLO (B) views demonstrate large irregular mass in the upper outer breast (white arrows). Nonenhanced CBCT (C) demonstrates known mass (crosshairs). In addition, an abnormal-appearing lymph node (D, crosshairs) is clearly seen in the axilla, not evident in the standard mammographic views. Repeat nonenhanced CBCT 6 months later following neoadjuvant chemotherapy (E) demonstrates interval enlargement of index lesion (with biopsy clip in place), consistent with lack of therapeutic response.

Fig. 5. Evaluation of response to therapy

66 year-old woman presents with palpable lump in the left breast. Mammographic CC (A)and MLO (B) views demonstrate large irregular mass in the upper outer breast (white arrows). Nonenhanced CBCT (C) demonstrates known mass (crosshairs). In addition, an abnormal-appearing lymph node (D, crosshairs) is clearly seen in the axilla, not evident in the standard mammographic views. Repeat nonenhanced CBCT 6 months later following neoadjuvant chemotherapy (E) demonstrates interval enlargement of index lesion (with biopsy clip in place), consistent with lack of therapeutic response.

Fig. 5. Evaluation of response to therapy

66 year-old woman presents with palpable lump in the left breast. Mammographic CC (A)and MLO (B) views demonstrate large irregular mass in the upper outer breast (white arrows). Nonenhanced CBCT (C) demonstrates known mass (crosshairs). In addition, an abnormal-appearing lymph node (D, crosshairs) is clearly seen in the axilla, not evident in the standard mammographic views. Repeat nonenhanced CBCT 6 months later following neoadjuvant chemotherapy (E) demonstrates interval enlargement of index lesion (with biopsy clip in place), consistent with lack of therapeutic response.

Fig. 5. Evaluation of response to therapy

66 year-old woman presents with palpable lump in the left breast. Mammographic CC (A)and MLO (B) views demonstrate large irregular mass in the upper outer breast (white arrows). Nonenhanced CBCT (C) demonstrates known mass (crosshairs). In addition, an abnormal-appearing lymph node (D, crosshairs) is clearly seen in the axilla, not evident in the standard mammographic views. Repeat nonenhanced CBCT 6 months later following neoadjuvant chemotherapy (E) demonstrates interval enlargement of index lesion (with biopsy clip in place), consistent with lack of therapeutic response.

Fig. 5. Evaluation of response to therapy

66 year-old woman presents with palpable lump in the left breast. Mammographic CC (A)and MLO (B) views demonstrate large irregular mass in the upper outer breast (white arrows). Nonenhanced CBCT (C) demonstrates known mass (crosshairs). In addition, an abnormal-appearing lymph node (D, crosshairs) is clearly seen in the axilla, not evident in the standard mammographic views. Repeat nonenhanced CBCT 6 months later following neoadjuvant chemotherapy (E) demonstrates interval enlargement of index lesion (with biopsy clip in place), consistent with lack of therapeutic response.