Correct determination of the enhancement curve is critical to ensure accurate diagnosis using the Kaiser score as a clinical decision rule for breast MRI

OBJECTIVES

the Kaiser score is increasingly recognized as a valuable tool to improve breast MRI interpretation. Contrast enhancement kinetics are the second most important diagnostic criterion, thus defining the curve type plays a crucial role in Kaiser score assessment. We investigate whether the timepoint used to determine the initial enhancement (earlyor peak) for the signal-intensity time curve analysis affects the diagnostic performance of the Kaiser score.

METHODS

This IRB-approved, retrospective, single-center study included 70 consecutives histologically verified breast MRI cases. Two off-site breast radiologists independently read all examinations using the Kaiser score, assessing the initial enhancement using three approaches: -first (1 st), second (2nd) and peak (maximum) of either 1 st or 2nd post-contrast timepoints. The initial enhancement was then compared to the last timepoint (delayed enhancement) to determine the curve type. Visual assessment of curve types was used for this study. Diagnostic performance was evaluated by receiver operating characteristics (ROC) analysis.

RESULTS

Kaiser score reading results using the peak enhancement of either the first or second timepoint performed significantly better than the other approaches (P < 0.05, respectively) and specifically achieved higher sensitivity. Diagnostic accuracy (AUC area under the curve) ranged between 85.4 % and 91.6 %, without significant differences between the two readers (P < 0.5).

CONCLUSIONS

Diagnostic performance of the Kaiser score is significantly influenced by how the initial enhancement timepoint is determined. Peak enhancement should be used as initial timepoint to avoid pitfalls due to timing or physiological differences.

Image-Guided Localization Techniques for Surgical Excision of Non-Palpable Breast Lesions: An Overview of Current Literature and Our Experience with Preoperative Skin Tattoo

Breast conserving surgery has become the standard of care and is more commonly performed than mastectomy for early stage breast cancer, with recent studies showing equivalent survival and lower morbidity. Accurate preoperative lesion localization is mandatory to obtain adequate oncological and cosmetic results. Image guidance assures the precision requested for this purpose. This review provides a summary of all techniques currently available, ranging from the classic wire positioning to the newer magnetic seed localization. We describe the procedures and equipment necessary for each method, outlining the advantages and disadvantages, with a focus on the cost-effective preoperative skin tattoo technique performed at our centre. Breast surgeons and radiologists have to consider ongoing technological developments in order to assess the best localization method for each individual patient and clinical setting.

Magnetic Resonance Imaging prediction of large volume displacement oncoplastic surgery versus mastectomy in the treatment of breast cancer

PURPOSE

To analyse the influence of tumor volume/breast volume ratio (TV/BV ratio) measured on magnetic resonance imaging (MRI) and other factors on surgeons' choice between large volume displacement oncoplastic surgery (LVOS) versus mastectomy (M) in patients with large sized tumors. Secondly, we investigate the predictive value of TV/BV ratio and other possible predictors for cosmetic results.

MATERIALS AND METHODS

We retrospectively reviewed 80 MRI examinations performed on 77 breast cancer patients who underwent M (58 breasts, 72.5%) or LVOS (22 breasts, 27.5%) at our institution between January 2016 and December 2017. The TV and BV measurements were performed by a semiautomated analysis and the TV/BV ratio was calculated by dividing TV by BV in cm3 and multiplying it by 1,000. Cosmetic result was determined by an expert panel assessment of postoperative photographs.

RESULTS

Median TV/BV was significantly higher in the M group (44,8 IQR 17,3-93,6) than in the LVOS group (17,5 IQR 11,7-57,5) (P=0.002). Multifocal/multicentric disease (P=0.005), lower degree of breast ptosis (P<0.0001) and unfavourable tumor location (P=0.024) are significantly more frequent in the M group. After multivariable linear regression, the independent predictors for cosmetic result were: unfavourable tumor location (OR 6.637 95% CI 1.564- 28.172 P=0.010) and a higher TV/BV ratio (OR 4.907 95% CI 1.461-16.478 P=0.010) CONCLUSION: Preoperative evaluation of TV/BV ratio, tumor location and tumor multifocality/multicentricity could improve treatment decision making (LVOS versus M) in breast cancer patient eligible for both options. Increasing TV/BV ratio and unfavourable tumor location are adversely affecting cosmetic result.

KEY WORDS

Breast cancer, Magnetic Resonance Imaging, Mastectomy, Large volume displacement oncoplastic surgery, Tumor volume/breast volume.

Morphological and Semiquantitative Kinetic Analysis on Dynamic Contrast Enhanced MRI in Triple Negative Breast Cancer Patients

RATIONALE AND OBJECTIVES

The aim of this study was to retrospectly investigate the association between different breast cancer (BC) immunohistochemical subtypes and morphological and semiquantitative kinetic analysis on breast magnetic resonance imaging (MRI) performed before surgery treatment. Specifically we aimed to assess MRI features of triple-negative breast cancer (TNBC) compared to the other BC subtypes (nTNBC).

MATERIALS AND METHODS

Patients undergone to breast MRI and then diagnosed with BC by core-needle biopsy were included. The MRI morphological and kinetic features were studied. Parametric and non-parametric tests were used, as appropriate.

RESULTS

Seventy-five BC patients were considered, 30 patients included in TNBC Group and 45 patients included in nTNBC Group. We found in TNBC Group a greater mean lesion size (P <0.001), a rim enhancement imaging (P=0.003), and a higher intratumoral signal intensity on T2-weighted images (P=0.03) with respect to nTNBC Group. We noticed that TNBC patients presented a lower grade of BPE when compared to the nTBC Group (P< 0.02). TNBC Group showed lower EPeak values (P=0.003) and higher SER values (P=0.02) with respect to the nTNBC Group. In addition, stratifying kinetics parameters according to the tumor grade, the TNBC Group presented higher tumor grade (G3) (P< 0.005) and this subgroup had higher SER values when compared to TNBCs showing a lower tumor grade (G1 and G2) (P=0.03).

CONCLUSION

After validation by large-scale studies, the morphological and semiquantitative kinetic analysis on dynamic contrast enhanced MRI may help in the pretreatment risk stratification of patients with TNBC and in evidence-based clinical decision support.

Usefulness of automated breast volume scanner (ABVS) for monitoring tumor response to neoadjuvant treatment in breast cancer patients: preliminary results

OBJECTIVE

We investigated the accuracy of Automated Breast Volume Scanner (ABVS) compared to handheld ultrasound (HHUS) for monitoring tumor response to neoadjuvant treatment (NAT) in breast cancer (BC).

PATIENTS AND METHODS

All the patients submitted to biopsy in our Institution, from January 2017 to May 2017, proven invasive BC and eligible for NAT, were enrolled in this prospective study. The participants underwent ABVS, HHUS, dynamic contrast-enhanced Magnetic Resonance Imaging (DCE-MRI) and mammography at the beginning of NAT and ABVS, HHUS and DCE-MRI at the halfway point of therapy and before the surgery. DCE-MRI was considered the standard of reference. Two breast radiologists (R1, R2), with fifteen and five years of experience in breast imaging, independently assigned a visibility score (ordinal 5-point scale) to ABVS, HHUS, and DCE-MRI. Diagnostic performance of ABVS and HHUS as measured by sensitivity, specificity, positive and negative predictive values (PPV and NPV) was calculated. Correlations between ABVS and MRI, and between HHUS and MRI were analyzed using Pearson's correlation test.

RESULTS

A total of 21 patients were enrolled. 189 examinations were performed. The comparison between ABVS and DCE-MRI was similar for the both readers: ABVS had a sensitivity of 63,16%, specificity of 83,58%, PPV of 76,60%, NPV of 72,73%, accuracy of 74,19% (R1) and a sensitivity of 54.54%, specificity of 85.51%, PPV of 75%, NPV of 70,24%, accuracy of 71.77% (R2). The comparison between HHUS and DCE-MRI showed that HHUS had a sensitivity of 63,16 %, specificity of 83,58%, PPV of 76,60%, NPV of 72,73%, accuracy of 74,19% (R1) and a sensitivity of 36.84%, specificity of 85.07%, PPV of 67.74%, NPV of 61.29%, accuracy of 62.90% (R2). The calculated Pearson's correlation coefficient r values were 7.8 for HHUS vs. DCE-MRI and 28.5 for ABVS vs. DCE-MRI (R1) and 7.8 for HHUS vs. DCE-MRI and 22.4 for ABVS vs. DCE-MRI (R2). Statistical significance of ABVS and HHUS was p < 0.0001 and 0.005 < p < 0.01, respectively (R1, R2).

CONCLUSIONS

DCE-MRI is recommended for the tumor response assessment. ABVS, a product of the biotechnology development, providing reproducible images, in addition to DCE-MRI, can be a potentially useful tool for the monitoring of response to NAT.

Effects of selected pectinolytic bacterial strains on water-retting of hemp and fibre properties

AIMS

To study the effect of selected bacterial strains on hemp water-retting and properties of retted fibre.

METHODS AND RESULTS

The trials were performed in laboratory tanks. The traditional water-retting process, without inoculum addition, was compared to a process modified by inoculating water tanks with two selected pectinolytic bacteria: the anaerobic strain Clostridium sp. L1/6 and the aerobic strain Bacillus sp. ROO40B. Six different incubation times were compared. Half the fibre obtained from each tank was combed. Micromorphological analyses were performed by scanning electron microscopy on uncombed and combed fibres. Moreover, organoleptic and chemical analyses of uncombed fibres were performed.

CONCLUSIONS

The inoculum, besides speeding up the process, significantly improved the fibre quality. The fibre was not damaged by mechanical hackling, thanks to the good retting level obtained by the addition of selected strains, differently to what happened with the traditionally retted fibre. The best fibre quality was obtained after 3-4 days of retting with the addition of the bacterial inoculum.

SIGNIFICANCE AND IMPACT OF THE STUDY

Retting is the major limitation to an efficient production of high-quality hemp fibres. The water-retting process and fibre quality were substantially improved by simultaneously inoculating water tanks with two selected pectinolytic strains.