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Microwave imaging for neoadjuvant chemotherapy monitoring: initial clinical experience.

Meaney PM, Kaufman PA, Muffly LS, Click M, Poplack SP, Wells WA, Schwartz GN, di Florio-Alexander RM, Tosteson TD, Li Z, Geimer SD, Fanning MW, Zhou T, Epstein NR, Paulsen KD - Breast Cancer Res. (2013)

Bottom Line: Two patient cases (one complete and one partial response) are presented in detail and demonstrate changes in microwave properties commensurate with the degree of treatment response observed pathologically.Normalized mean conductivity in ROIs from patients with complete pathological responses was significantly different from that of partial responders (P value = 0.004).In addition, the normalized conductivity measure also correlated well with complete pathological response at 30 days (P value = 0.002).

View Article: PubMed Central - HTML - PubMed

ABSTRACT

Introduction: Microwave tomography recovers images of tissue dielectric properties, which appear to be specific for breast cancer, with low-cost technology that does not present an exposure risk, suggesting the modality may be a good candidate for monitoring neoadjuvant chemotherapy.

Methods: Eight patients undergoing neoadjuvant chemotherapy for locally advanced breast cancer were imaged longitudinally five to eight times during the course of treatment. At the start of therapy, regions of interest (ROIs) were identified from contrast-enhanced magnetic resonance imaging studies. During subsequent microwave examinations, subjects were positioned with their breasts pendant in a coupling fluid and surrounded by an immersed antenna array. Microwave property values were extracted from the ROIs through an automated procedure and statistical analyses were performed to assess short term (30 days) and longer term (four to six months) dielectric property changes.

Results: Two patient cases (one complete and one partial response) are presented in detail and demonstrate changes in microwave properties commensurate with the degree of treatment response observed pathologically. Normalized mean conductivity in ROIs from patients with complete pathological responses was significantly different from that of partial responders (P value = 0.004). In addition, the normalized conductivity measure also correlated well with complete pathological response at 30 days (P value = 0.002).

Conclusions: These preliminary findings suggest that both early and late conductivity property changes correlate well with overall treatment response to neoadjuvant therapy in locally advanced breast cancer. This result is consistent with earlier clinical outcomes that lesion conductivity is specific to differentiating breast cancer from benign lesions and normal tissue.

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Related in: MedlinePlus

1300 MHz microwave tomographic images of the contralateral breast for Patient 8. Imaging planes one to four are shown corresponding to the four closest planes to the chest wall with the permittivity on the top and conductivity on the bottom row, respectively. (a) Prior to treatment, (b) day 33, and (c) day 62.
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Figure 8: 1300 MHz microwave tomographic images of the contralateral breast for Patient 8. Imaging planes one to four are shown corresponding to the four closest planes to the chest wall with the permittivity on the top and conductivity on the bottom row, respectively. (a) Prior to treatment, (b) day 33, and (c) day 62.

Mentions: For comparison, we also collected data from the contralateral breast when possible (that is, examination time-permitting, patient not feeling ill, and so on) and show example images from planes one to four for Patient #8 at the first date, day 33 and day 62 after the start of treatment (Figure 8). In these images, the permittivity and conductivity outlines of the breast are evident in terms of a property gradient with the background coupling fluid. As the images progress from plane one to four, the overall breast diameter decreases - a feature that is more obvious in the conductivity results. In the permittivity images, an annulus of lower property tissue surrounds a more elevated zone in each of the four planes. This central region contains more fibroglandular tissue for which higher permittivity properties are expected relative to the surrounding adipose tissue. In the conductivity images, the first two planes also show elevated property zones towards the lower right quadrant; however, they begin to disappear in planes three and four as the overall size of the breast cross-section shrinks, and the increased fibroglandular tissue properties begin to blur with the higher properties of the surrounding coupling liquid. The images for all three examination dates are similar and do not suggest significant changes other than from minor shifting of the position of the breast within the field of view.


Microwave imaging for neoadjuvant chemotherapy monitoring: initial clinical experience.

Meaney PM, Kaufman PA, Muffly LS, Click M, Poplack SP, Wells WA, Schwartz GN, di Florio-Alexander RM, Tosteson TD, Li Z, Geimer SD, Fanning MW, Zhou T, Epstein NR, Paulsen KD - Breast Cancer Res. (2013)

1300 MHz microwave tomographic images of the contralateral breast for Patient 8. Imaging planes one to four are shown corresponding to the four closest planes to the chest wall with the permittivity on the top and conductivity on the bottom row, respectively. (a) Prior to treatment, (b) day 33, and (c) day 62.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3672734&req=5

Figure 8: 1300 MHz microwave tomographic images of the contralateral breast for Patient 8. Imaging planes one to four are shown corresponding to the four closest planes to the chest wall with the permittivity on the top and conductivity on the bottom row, respectively. (a) Prior to treatment, (b) day 33, and (c) day 62.
Mentions: For comparison, we also collected data from the contralateral breast when possible (that is, examination time-permitting, patient not feeling ill, and so on) and show example images from planes one to four for Patient #8 at the first date, day 33 and day 62 after the start of treatment (Figure 8). In these images, the permittivity and conductivity outlines of the breast are evident in terms of a property gradient with the background coupling fluid. As the images progress from plane one to four, the overall breast diameter decreases - a feature that is more obvious in the conductivity results. In the permittivity images, an annulus of lower property tissue surrounds a more elevated zone in each of the four planes. This central region contains more fibroglandular tissue for which higher permittivity properties are expected relative to the surrounding adipose tissue. In the conductivity images, the first two planes also show elevated property zones towards the lower right quadrant; however, they begin to disappear in planes three and four as the overall size of the breast cross-section shrinks, and the increased fibroglandular tissue properties begin to blur with the higher properties of the surrounding coupling liquid. The images for all three examination dates are similar and do not suggest significant changes other than from minor shifting of the position of the breast within the field of view.

Bottom Line: Two patient cases (one complete and one partial response) are presented in detail and demonstrate changes in microwave properties commensurate with the degree of treatment response observed pathologically.Normalized mean conductivity in ROIs from patients with complete pathological responses was significantly different from that of partial responders (P value = 0.004).In addition, the normalized conductivity measure also correlated well with complete pathological response at 30 days (P value = 0.002).

View Article: PubMed Central - HTML - PubMed

ABSTRACT

Introduction: Microwave tomography recovers images of tissue dielectric properties, which appear to be specific for breast cancer, with low-cost technology that does not present an exposure risk, suggesting the modality may be a good candidate for monitoring neoadjuvant chemotherapy.

Methods: Eight patients undergoing neoadjuvant chemotherapy for locally advanced breast cancer were imaged longitudinally five to eight times during the course of treatment. At the start of therapy, regions of interest (ROIs) were identified from contrast-enhanced magnetic resonance imaging studies. During subsequent microwave examinations, subjects were positioned with their breasts pendant in a coupling fluid and surrounded by an immersed antenna array. Microwave property values were extracted from the ROIs through an automated procedure and statistical analyses were performed to assess short term (30 days) and longer term (four to six months) dielectric property changes.

Results: Two patient cases (one complete and one partial response) are presented in detail and demonstrate changes in microwave properties commensurate with the degree of treatment response observed pathologically. Normalized mean conductivity in ROIs from patients with complete pathological responses was significantly different from that of partial responders (P value = 0.004). In addition, the normalized conductivity measure also correlated well with complete pathological response at 30 days (P value = 0.002).

Conclusions: These preliminary findings suggest that both early and late conductivity property changes correlate well with overall treatment response to neoadjuvant therapy in locally advanced breast cancer. This result is consistent with earlier clinical outcomes that lesion conductivity is specific to differentiating breast cancer from benign lesions and normal tissue.

Show MeSH
Related in: MedlinePlus