Is there a role for positron emission tomography in breast cancer staging?

Association between age and the presence and mortality of breast cancer synchronous brain metastases in the United States: A neglected SEER analysis

BACKGROUND

The extent of the relationship between age and the presence of breast cancer synchronous brain metastases (BCSBMs) and mortality has not yet been well-identified or sufficiently quantified. We aimed to examine the association of age with the presence of BCSBMs and all-cause and cancer-specific mortality outcomes using the SEER database.

METHODS

Age-associated risk of the presence and survival of BCSBMs were evaluated on a continuous scale (restricted cubic spline, RCS) with logistic or Cox regression models. The main endpoints were the presence of BCSBMs and all-cause mortality or cancer-specific mortality. Cox proportional hazards regression and competing risk models were used in survival analysis.

RESULTS

Among 374,132 adult breast cancer patients, 1,441 (0.38%) had BMs. The presence of BCSBMs displayed a U-shaped relationship with age, with the highest point of the curve occurring at the age of 62. In both the younger (age ≤ 61) and older (age ≥ 62) groups, the observed curve showed a nearly linear relationship between age and the presence of BCSBMs. The relationship between age and all-cause mortality (ASM) and cancer-specific mortality (CSM) was linear. Older age at diagnosis was associated with a higher risk of ASM (HR 1.019, 95% CI: 1.013-1.024, p < 0.001) and CSM (HR 1.016, 95% CI: 1.010-1.023, p < 0.001) in multivariable Cox models. Age (sHR 1.007, 95% CI 1-1.013, p = 0.049) was substantially related to a significantly increased risk of CSM in competing risk models.

CONCLUSION

Age had a non-linear U-shaped relationship with the presence of BCSBMs and a linear relationship with BCSBMs mortality.

The Effect of PACS in Breast Tumor Diagnosis Based on Numerical Analysis

The incidence and mortality rates are increasing year by year, and the incidence of the disease is gradually becoming younger. The purpose of this study was to investigate the clinical diagnostic value of PACS in breast tumor patients. Methods. 20 patients with breast tumor diagnosed by PACS were selected for the study, and the diagnosis was confirmed by pathological puncture or surgery. Results. The detection rates of breast tumor by MRI and CT were 94.44% and 96.67%, the sensitivities were 18.82% breast tumor and 96.67%, and the specificities were 53.84% and 54.54%, with no statistically significant difference ( $P>0.05$ ). There was no statistically significant difference in the detection rate of invasive lobular carcinoma (LDC) and PACS ( $P>0.05$ ). Conclusion. PACS has a greater detection rate for breast tumor and offers some diagnostic usefulness in diagnosing malignant breast tumor. The detection rate of breast tumors can be increased by selecting the most appropriate diagnostic tool for the patient’s current circumstances.

Development of a mechatronic guidance system for targeted ultrasound-guided biopsy under high-resolution positron emission mammography localization

PURPOSE

Image-guided needle biopsy of small, detectable lesions is crucial for early-stage diagnosis, treatment planning, and management of breast cancer. High-resolution positron emission mammography (PEM) is a dedicated functional imaging modality that can detect breast cancer independent of breast tissue density, but anatomical context and real-time needle visualization are not yet available to guide biopsy. We propose a mechatronic guidance system integrating an ultrasound (US)-guided core-needle biopsy (CNB) with high-resolution PEM localization to improve the spatial sampling of breast lesions. This paper presents the benchtop testing and phantom studies to evaluate the accuracy of the system and its constituent components for targeted PEM-US-guided biopsy under simulated high-resolution PEM localization.

METHODS

A mechatronic guidance system was developed to operate with the Radialis PEM system and a conventional US system. The system includes a user-operated guidance arm and end-effector biopsy device, integrating a US transducer and CNB gun, with its needle focused on a remote center of motion (RCM). Custom software modules were developed to track, display, and guide the end-effector biopsy device. Registration of the mechatronic guidance system to a simulated PEM detector plate was performed using a landmark-based method. Testing was performed with fiducials positioned in the peripheral and central regions of the simulated detector plate and registration error was quantified. Breast phantom experiments were performed under ideal detection and localization to evaluate for bias in the end-effector biopsy device. The accuracy of the complete mechatronic guidance system to perform targeted breast biopsy was assessed using breast phantoms with simulated lesions. Three-dimensional positioning error was quantified, and principal component analysis assessed for directional trends in 3D space within 95% prediction intervals. Targeted breast biopsies with test phantoms were performed and an overall in-plane needle targeting error was quantified.

RESULTS

The mean registration errors were 0.63 mm (N = 44) and 0.73 mm (N = 72) in the peripheral and central regions of the simulated PEM detector plate, respectively. A 3D 95% prediction ellipsoid shows an error volume <2.0 mm in diameter, centered on the mean registration error. Under ideal detection and localization, targets <1.0 mm in diameter can be sampled with 95% confidence. The complete mechatronic guidance system was able to successfully spatially sample simulated breast lesions, 4 mm and 6 mm in diameter and height (N = 20) in known 3D positions in the PEM image coordinate space. The 3D positioning error was 0.85 mm (N = 20) with 0.64 mm in-plane and 0.44 mm cross-plane component errors. Targeted breast biopsies resulted in a mean in-plane needle targeting error of 1.08 mm (N = 15) allowing for targets 1.32 mm in radius to be sampled with 95% confidence.

CONCLUSIONS

We demonstrated the utility of our mechatronic guidance system for targeted breast biopsy under high-resolution PEM localization. Breast phantom studies showed the ability to accurately guide, position, and target breast lesions with the accuracy to spatially sample targets <3.0 mm in diameter with 95% confidence. Future work will integrate the developed system with the Radialis PEM system toward combined PEM-US-guided breast biopsy.

Relationship Between FDG Uptake and the Platelet/lymphocyte Ratio in Patients With Breast Invasive Ductal Cancer

BACKGROUND/AIM

We investigated the relationship between F18-fluorodeoxyglucose (FDG) uptake and the platelet/lymphocyte ratio (PLR), as both represent inflammation.

PATIENTS AND METHODS

We retrospectively analyzed the cases of 143 consecutive invasive ductal carcinoma patients who had undergone preoperative FDG-PET and surgery. We divided the patients into groups based on their maximum standardized uptake value (SUVmax) values: low (<2.5) and high (≥2.5) and based on their PLRs: low (<130) and high (≥130). We determined the relationships between the SUVmax or PLR and clinicopathological features.

RESULTS

Seventy-three patients (51.0%) had a high SUVmax in their primary tumor. There were significant associations between SUVmax and the PLR. A multivariate analysis revealed that high PLR, but not NLR, was independent factor associated with a high SUVmax. Seventy-four patients (51.7%) had a high PLR; The factors significantly associated with high PLR were large tumor size, presence of node metastasis, presence of vascular invasion, high NLR, and high SUVmax.

CONCLUSION

In breast cancer patients, the PLR is independently associated with the SUVmax, but not with recurrent disease. In breast cancer patients with a high SUVmax and/or PLR, these values may reflect the tumor microenvironment.

A machine learning-based radiomics model for the prediction of axillary lymph-node metastasis in breast cancer

OBJECTIVE

The aim of this study was to develop and validate machine learning-based radiomics model for predicting axillary lymph-node (ALN) metastasis in invasive ductal breast cancer (IDC) using F-18 fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT).

METHODS

A total of 100 consecutive IDC patients who underwent surgical resection of primary tumor with sentinel lymph-node biopsy and/or ALN dissection without any neoadjuvant treatment were analyzed. Volume of interests (VOIs) were drawn more than 2.5 of standardized uptake value in the primary tumor on the PET scan using 3D slicer. Pyradiomics package was used for the extraction of texture features in python. The radiomics prediction model for ALN metastasis was developed in 75 patients of the training cohort and validated in 25 patients of the test cohort. XGBoost algorithm was utilized to select features and build radiomics model. The sensitivity, specificity, and accuracy of the predictive model were calculated.

RESULTS

ALN metastasis was found in 43 patients (43%). The sensitivity, specificity, and accuracy of F-18 FDG PET/CT for the diagnosis of ALN metastasis in the entire patients were 55.8%, 93%, and 77%, respectively. The radiomics model for the prediction of ALN metastasis was successfully developed. The sensitivity, specificity, and accuracy of the radiomics model for the prediction of ALN metastasis in the test cohorts were 90.9%, 71.4%, and 80%, respectively.

CONCLUSION

The machine learning-based radiomics model showed good sensitivity for the prediction of ALN metastasis and could assist the preoperative individualized prediction of ALN status in patients with IDC.

Chest Wall Reconstruction with a Bilayered Wound Matrix Mesh Following Toilet Mastectomy

Patient: Female, 43

Final Diagnosis: Metastatic breast cancer

Symptoms: Breast lesion, breast tumor

Medication: —

Clinical Procedure: Chest wall reconstruction with a bilayered wound matrix mesh following toilet mastectomy

Specialty: Surgery

Predictive Value of 18F-FDG PET/CT for Axillary Lymph Node Metastasis in Invasive Ductal Breast Cancer

BACKGROUND

This study assessed whether primary tumor maximum standardized uptake value (pSUV_max) measured by ¹⁸F-fluoro-2-deoxy-D-glucose (¹⁸F-FDG) positron emission tomography/computed tomography (PET/CT) could improve the prediction of axillary lymph node (ALN) metastasis in invasive ductal breast cancer (IDC).

METHODS

In this study, 128 IDC patients who underwent pretreatment ¹⁸F-FDG PET/CT and surgical resection of primary tumor with sentinel lymph node biopsy, ALN dissection, or both were analyzed. All the patients were classified as five molecular subtypes. The optimal cutoff values of pSUVmax for all the patients and each molecular subtype for the prediction of ALN metastasis were determined using receiver operating characteristic (ROC) analysis. Furthermore, the prognostic accuracy of ALN metastasis was assessed using c-statistics.

RESULTS

The findings showed ALN metastasis in 52 patients (40.6%). The ¹⁸F-FDG PET/CT procedure had a sensitivity of 48.1% and a specificity of 94.7% for ALN metastasis. In the ROC analysis of pSUVmax for ALN metastasis, the optimal cutoff value was 3.9 for all the patients, 2.8 for the luminal A subtype, 3.3 for the luminal B (human epidermal growth factor receptor 2 [HER2]-negative) subtype, 5.3 for the luminal B (HER2-positive) subtype, 12.7 for the HER2-positive subtype, and 11.5 for the triple-negative subtype. A predictive ALN metastasis model using nodal ¹⁸F-FDG uptake finding gave a c-statistic of 0.714, and a model combination of nodal ¹⁸F-FDG uptake finding with pSUV_max of all the patients gave a c-statistic of 0.736 (P = 0.3926). However, the combination of nodal the ¹⁸F-FDG uptake finding with the pSUV_max of each molecular subtype gave a c-statistic of 0.791 (P = 0.0047).

CONCLUSIONS

Combining the pSUV_max of each molecular subtype with the nodal ¹⁸F-FDG uptake finding can improve the prediction of ALN metastasis in IDC.

Potential Clinical Applications of 18F-Fluorodeoxyglucose Positron Emission Tomography/Magnetic Resonance Mammography in Breast Cancer

The whole-body positron emission tomography (PET)/magnetic resonance (MR) scan is a cutting edge technology providing comprehensive structural information from MR imaging and functional features from PET in a single session. Recent research findings and clinical experience have shown that ¹⁸F-fluorodeoxyglucose (FDG) whole-body PET/MR imaging has a diagnostic performance comparable with or superior to that of PET/CT in the field of oncology, including for breast cancer. In particular, FDG PET/MR mammography in the prone position with the breast hanging in a pendant manner can provide more comprehensive information about the metabolism, anatomy, and functional features of a breast lesion than a whole-body PET/MR scan. This article reports on current state-of-the-art PET/MR mammography in patients with breast cancer and the prospects for potential application in the future.

Is sentinel lymph node biopsy a viable alternative to complete axillary dissection following neoadjuvant chemotherapy in women with node-positive breast cancer at diagnosis? An updated meta-analysis involving 3,398 patients

BACKGROUND

The use of sentinel lymph node biopsy (SLNB) following neoadjuvant chemotherapy (NAC) in patients presenting with clinically positive lymph nodes remains controversial.

METHODS

A computer-aided search of the literature regarding SLNB in clinically node-positive breast cancer treated with NAC was carried out to identify the false negative rate (FNR), sentinel lymph node identification rate (IR), and axillary pathological complete response (pCR).

RESULTS

Nineteen articles were used in the analysis yielding 3,398 patients. The pooled estimate of the FNR was 13% and that of the IR was 91%. The adjusted pCR rate was 47%. A trend toward significance was observed with only clinical stage N1 (cN1) disease whereby clinical stage N1 was associated with an increased pCR rate when compared to N2 or N3 disease (P = .06).

CONCLUSIONS

SLNB after NAC in biopsy-proven node-positive patients results in reasonably acceptable FNR and IR, making it a valid alternative management strategy to axillary dissection. More refined patient selection and optimal techniques can improve the FNR and IR in this patient population.

Positron Emission Tomography in Breast Cancer

Gradually, FDG-PET/CT has been strengthening within the diagnostic algorithms of oncological diseases. In many of these, PET/CT has shown to be useful at different stages of the disease: diagnosis, staging or re-staging, treatment response assessment, and recurrence. Some of the advantages of this imaging modality versus CT, MRI, bone scan, mammography, or ultrasound, are based on its great diagnostic capacity since, according to the radiopharmaceutical used, it reflects metabolic changes that often occur before morphological changes and therefore allows us to stage at diagnosis. Moreover, another advantage of this technique is that it allows us to evaluate the whole body so it can be very useful for the detection of distant disease. With regard to breast cancer, FDG-PET/CT has proven to be important when recurrence is suspected or in the evaluation of treatment response. The technological advancement of PET equipment through the development of new detectors and equipment designed specifically for breast imaging, and the development of more specific radiopharmaceuticals for the study of the different biological processes of breast cancer, will allow progress not only in making the diagnosis of the disease at an early stage but also in enabling personalized therapy for patients with breast cancer.

A New Isolated Mediastinal Lymph Node or Small Pulmonary Nodule Arising during Breast Cancer Surveillance Following Curative Surgery: Clinical Factors That Differentiate Malignant from Benign Lesions

PURPOSE

A newly isolated mediastinal lymph node (LN) or a small pulmonary nodule, which appears during breast cancer surveillance, may pose a diagnostic dilemma with regard to malignancy. We conducted this study to determine which clinical factors were useful for the differentiation of malignant lesions from benign lesions under these circumstances.

MATERIALS AND METHODS

We enrolled breast cancer patients who were presented with a new isolated mediastinal LN or small pulmonary nodule that arose during surveillance, and whose lesions were pathologically confirmed. Tissue diagnosis was made by mediastinoscopy, video-assisted thoracic surgery or thoracotomy.

RESULTS

A total of 43 patients were enrolled (mediastinal LN, 13 patients; pulmonary nodule, 30 patients). Eighteen patients (41.9%) were pathologically confirmed to have a benign lesion (benign group), and 25 patients (58.1%) were confirmed to have malignant lesion (malignant group). Between the two groups, the initial tumor size (p=0.096) and N stage (p=0.749) were similar. Hormone receptor negativity was more prevalent in the malignant group (59.1% vs. 40.9%, p=0.048). The mean lesion size was larger in the malignant group than in the benign group (20.8 mm vs. 14.4 mm, p=0.024). Metastatic lesions had a significantly higher value of maximal standardized uptake (mSUV) than that of benign lesions (6.4 vs. 3.4, p=0.021).

CONCLUSION

Hormone receptor status, lesion size, and mSUV on positron emission tomography are helpful in the differentiation of malignant lesions from benign lesions in breast cancer patients who were presented with a new isolated mediastinal LN or small pulmonary nodule during surveillance.

Additional value of F-18 FDG PET/CT for initial staging in breast cancer with clinically negative axillary nodes

The aim of this study was to evaluate the clinical impact of the preoperative ¹⁸F-FDG PET/CT in the initial workup of breast cancer with clinically negative axillary nodes. Whether the status of the clinical axillary nodal involvement can be considered a parameter for making a decision to omit the preoperative ¹⁸F-FDG PET/CT in the situation reported herein was also determined. A total of 178 patients who had newly diagnosed breast cancer and for whom the conventional diagnostic modalities showed no sign of axillary node metastasis were retrospectively enrolled in this study. All the patients underwent preoperative ¹⁸F-FDG PET/CT. The images and histologic results that were obtained were analyzed. ¹⁸F-FDG PET/CT detected primary lesions in 156 of the 178 patients, with an overall sensitivity of 87.6 %, and false negative results were obtained for 22 patients (12.4 %). The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of ¹⁸F-FDG PET/CT in the detection of axillary nodes were 20.8, 86.9, 37.0, 74.8, and 69.1 %, respectively. Extra-axillary node metastasis was identified in two patients (1.1 %) who had internal mammary nodes. There was no distant metastasis, but coexisting primary tumor was detected in five patients (2.8 %). In total, the therapeutic plan was changed based on ¹⁸F-FDG PET/CT in seven (3.9 %) of the 178 patients, but considering only the cases confined to breast cancer, the change occurred in only two patients (1.1 %). ¹⁸F-FDG PET/CT almost did not affect the initial staging and treatment plan in breast cancer with clinically negative axillary node. If the axillary node is clinically negative in the preoperative workup of breast cancer, then ¹⁸F-FDG PET/CT can be omitted.

Different biological and prognostic breast cancer populations identified by FDG-PET in sentinel node-positive patients: results and clinical implications after eight-years follow-up

BACKGROUND

Sentinel node (SN) biopsy is the standard method to evaluate axillary node involvement in breast cancer (BC). Positron emission tomography with 2-(fluorine-18)-fluoro-2-deoxy-D-glucose (FDG-PET) provides a non-invasive tool to evaluate regional nodes in BC in a metabolic-dependent, biomolecular-related way. In 1999, we initiated a prospective non-randomized study to compare these two methods and to test the hypothesis that FDG-PET results reflect biomolecular characteristics of the primary tumor, thereby yielding valuable prognostic information.

PATIENTS AND METHODS

A total of 145 cT1N0 BC patients, aged 24-70 years, underwent FDG-PET and lymphoscintigraphy before surgery. SN biopsy was followed in all cases by complete axillary dissection. Pathologic evaluation in tissue sections for involvement of the SN and other non-SN nodes served as the basis of the comparison between FDG-PET imaging and SN biopsy.

RESULTS

FDG-PET and SN biopsy sensitivity was 72.6% and 88.7%, respectively, and negative predictive values were 80.5% and 92.2%, respectively. A subgroup of more aggressive tumors (ER-GIII, Her2+) was found mainly in the FDG-PET true-positive (FDG-PET+) patients, whereas LuminalA, Mib1 low-rate BCs were significantly undetected (p = 0.009) in FDG-PET false-negative (FDG-PET-) patients. Kaplan-Meier survival estimates after a median follow-up of more than 8 years showed significantly worse overall survival for FDG-PET+ patients in node-positive (N+) patients (p = 0.035) as compared to N+/FDG-PET- patients, which overlapped with survival curves of N- and FDG-PET+ or - patients.

CONCLUSIONS

Our findings suggest that FDG-PET results reflect intrinsic biologic features of primary BC tumors and have prognostic value with respect to nodal metastases. FDG-PET false negative cases appear to identify less aggressive indolent metastases. The possibility to identify a subgroup of N+ BC patients with an outcome comparable with N- BC patients could reduce the surgical and adjuvant therapeutic intervention.

Radionuclide methods for breast cancer staging

Staging at initial presentation is one of the important prognostic factors for patients with breast cancer. Depending on the extent of disease spread, staging is divided into locoregional and distant or systemic. Locoregional staging includes axillary and internal mammary lymph node evaluation and distant or systemic staging includes evaluation of sites beyond the lymph node. Fluorodeoxyglucose-positron emission tomography (FDG-PET) is not sensitive to detect small metastasis in axillary lymph node. The current standard of axillary lymph node staging in early-stage breast cancer is therefore sentinel lymph node biopsy. Internal mammary lymph nodes are not commonly included in routine staging. In advanced-stage breast cancer, FDG-PET and PET/computed tomography (CT) are the modalities of choice to evaluate locoregional and distant metastasis. FDG-PET and PET/CT often detect occult metastasis, which is not visible on any other modalities including diagnostic CT scan. Detection of occult metastasis may potentially change in treatment options. This is particularly important in locally advanced breast cancer, which tends to develop early distant metastasis.

Accuracy of 18F-FDG PET/CT for primary tumor visualization and staging in T1 breast cancer

BACKGROUND

The aim of this study was to assess the accuracy of 18F-FDG PET/CT in T1 breast cancer regarding visualization of the primary tumor and the detection of locoregional and distant metastases.

METHODS

Sixty-two women with invasive T1 breast cancer underwent a PET/CT. Image acquisition of the thorax was done in prone position with hanging breasts, followed by whole-body scanning in supine position. Primary tumor FDG uptake was evaluated and compared with clinical and histopathological characteristics. Presence of locoregional and distant metastases was assessed and compared with conventional imaging procedures.

RESULTS

The primary tumor was visible with PET/CT in 54 (87%) of 62 patients, increasing from 59% (10/17) in tumors ≤ 10 mm to 98% (44/45) in tumors over 10 mm. All triple negative and HER2-positive tumors and 40/48 (83%) ER-positive/HER2-negative tumors were visualized. Sensitivity and specificity of PET/CT in the detection of axillary metastases were 73% and 100%, respectively. PET/CT depicted periclavicular nodes in two patients. Of 12 distant lesions, one was confirmed to be a lung metastasis, three were false positive, and eight were new primary proliferative lesions.

CONCLUSION

Using optimal imaging acquisition, the majority of T1 breast carcinomas can be visualized with PET/CT. Specificity in the detection of axillary metastases is excellent, but sensitivity appears to be limited. Additional whole body imaging has a low yield in this specific patient group.

The Prognostic Value of (18)F-FDG PET/CT for Early Recurrence in Operable Breast Cancer: Comparison with TNM Stage

PURPOSE

We evaluated whether the maximum standardized uptake values (SUVmax) of primary tumor from the initial staging by (18)F-fluorodeoxyglucose positron emission tomography/computed tomography ((18)F-FDG PET/CT) of patients with breast cancer could identify patients at risk for early recurrence within 2 years, particularly in comparison to the American Joint Committee on Cancer (AJCC) stage.

METHODS

We reviewed the staging (18)F-FDG PET/CT images of patients with primary breast cancer and their medical records. The SUVmax of the primary tumor was measured. The presence or absence of FDG uptake in the axillary lymph node (ALN) was also assessed. The patient's pathologic primary tumor stage (pT), pathologic regional lymph node stage (pN), stage grouping, age, estrogen receptor (ER) and progesterone receptor (PR) status, and neoadjuvant chemotherapy history were evaluated with the FDG uptake parameters for recurrence within 2 years following the end of first-line therapy.

RESULTS

Recurrence within 2 years was present in 9.1 % (n = 40) out of the 441 patients assessed. The FDG uptake in ALN, pT, pN, stage grouping and neoadjuvant chemotherapy history were prognostic for early recurrence, while primary tumor SUVmax, age, and ER or PR status were not significant on logistic regression. On multivariate analysis, only the stage grouping (odds ratio 2.79; 95 % CI 1.73, 4.48; p < 0.0001) and neoadjuvant chemotherapy history (odds ratio 2.70; 95 % CI 1.22, 5.98; p = 0.0141) could identify patients at increased risk for recurrence within 2 years.

CONCLUSIONS

Primary tumor FDG uptake measured by SUVmax, and visual assessment of FDG uptake in the ALN in the initial staging PET/CT of patients with breast cancer may not have additional prognostic value compared with the AJCC stage grouping for early recurrence.

Predictive value of PET-CT for pathological response in stages II and III breast cancer patients following neoadjuvant chemotherapy with docetaxel

PURPOSE

To prospectively study the value of PET-CT with fluorine-18 fluorodeoxyglucose (FDG) to predict neoadjuvant chemotherapy (NAC) response of locoregional disease of stages II and III breast cancer patients.

MATERIAL AND METHODS

A written informed consent and approval were obtained from the Ethics Committee. PET-CT accuracy in the prediction of pathologic complete response (pCR) after NAC was studied in primary tumors and lymph node metastasis in 43 women (mean age: 50 years: range: 27-71 years) with histologically proven breast cancer between December 2009 and January 2011. PET-CT was performed at baseline and after NAC. SUV(max) percentage changes (ΔSUV(max)) were compared with pathology findings at surgery. Receiver-operator characteristic (ROC) analysis was used to discriminate between locoregional pCR and non-pCR. In patients not achieving pCR, it was investigated if ΔSUV(max) could accurately identify the residual cancer burden (RCB) classes: RCB-I (minimal residual disease (MRD)), RCB-II (moderate RD), and RCB-III (extensive RD).

RESULTS

pCR was obtained in 11 patients (25.6%). Residual disease was found in 32 patients (74.4%): 16 (37.2%) RCB-I, 15 (35.6%) RCB-II and 2 (4.7%) RCB-III. Sensitivity, specificity, and accuracy to predict pCR were 90.9%, 90.6%, and 90.7%, respectively. Specificity was 94.1% in the identification of a subset of patients who had either pCR or MRD.

CONCLUSION

Accuracy of ΔSUV(max) in the locoregional disease of stages II and III breast cancer patients after NAC is high for the identification of pCR cases. Its specificity is potentially sufficient to identify a subgroup of patients who could be managed with conservative surgery.

Dual time point 2-deoxy-2-[18F]fluoro-D-glucose PET/CT: nodal staging in locally advanced breast cancer

AIM

To assess dual time point 2-deoxy-2-[(18)F]fluoro-D-glucose (18)(F)FDG PET-CT accuracy in nodal staging and in detection of extra-axillary involvement.

MATERIAL AND METHODS

Dual time point [(18)F] FDG PET/CT scan was performed in 75 patients. Visual and semiquantitative assessment of lymph nodes was performed. Semiquantitative measurement of SUV and ROC-analysis were carried out to calculate SUV(max) cut-off value with the best diagnostic performance. Axillary and extra-axillary lymph node chains were evaluated.

RESULTS

Sensitivity and specificity of visual assessment was 87.3% and 75%, respectively. SUV(max) values with the best sensitivity were 0.90 and 0.95 for early and delayed PET, respectively. SUV(max) values with the best specificity were 1.95 and 2.75, respectively. Extra-axillary lymph node involvement was detected in 26.7%.

CONCLUSION

FDG PET/CT detected extra-axillary lymph node involvement in one-fourth of the patients. Semiquantitative lymph node analysis did not show any advantage over the visual evaluation.

Predictive value of FDG PET/CT for pathologic axillary node involvement after neoadjuvant chemotherapy

BACKGROUND

The purpose of this study was to determine the usefulness of sequential FDG PET/CTs for prediction of axillary lymph node (ALN) status after neoadjuvant chemotherapy (NAC).

METHODS

Seventy-seven stage II or III breast cancer patients who received 3 cycles of neoadjuvant docetaxel/doxorubicin chemotherapy were enrolled in this prospective study. FDG PET/CTs were acquired before chemotherapy and after the first cycle of chemotherapy for early metabolic response prediction.

RESULTS

Patients with pN0 had significantly lower post-NAC ALN standard uptake value (SUV) than those who were pN+ (1.22 ± 1.46 in pN0 vs. 2.13 ± 1.99 in pN+, P = 0.017). Post-NAC ALN size on CT also differed according to pathologic ALN status (6.3 mm in pN0 vs. 11.1 mm in pN+, P = 0.014). When serial FDG PET/CT and chest CT were used, patients with an SUV > 1.5 and post-NAC ALN size ≥10 mm on CT did not achieve pN0 (specificity 100% and positive predictive value 100%).

CONCLUSIONS

The serial FDG PET/CT after NAC could predict the pathologic status of ALN before surgery in stage II/III breast cancer. Our findings suggest that the combined use of serial FDG PET/CTs and chest CT might provide better information regarding ALN before surgery.

Diagnostic and prognostic application of positron emission tomography in breast imaging: emerging uses and the role of PET in monitoring treatment response

Positron emission tomography (PET) is an imaging modality that using radiotracers, permits real-time dynamic monitoring of biologic processes such as cell metabolic behavior and proliferation, and has proven useful as a research tool for understanding tumor biology. While it does not have a well-defined role in breast cancer for the purposes of screening, diagnosis, or prognosis, emerging PET technologies and uses could expand the applications of PET in breast cancer. Positron emission mammography may provide an alternative adjunct imaging modality for the screening and diagnosis of high-risk patients unable to tolerate MRI. The development of radiotracers with the ability to measure hormonal activity could provide a non-invasive way to assess hormone receptor status and functionality. Finally, the role of PET technologies in monitoring early treatment response may prove particularly useful to research involving new therapeutic interventions.

Association of primary tumour FDG uptake with clinical, histopathological and molecular characteristics in breast cancer patients scheduled for neoadjuvant chemotherapy

PURPOSE

The aim of this study was to evaluate the association of primary tumour (18)F-fluorodeoxyglucose (FDG) uptake with clinical, histopathological and molecular characteristics of breast cancer patients scheduled for neoadjuvant chemotherapy. Second, we wished to establish for which patients pretreatment positron emission tomography (PET)/CT could safely be omitted because of low FDG uptake.

METHODS

PET/CT was performed in 214 primary stage II or III breast cancer patients in the prone position with hanging breasts. Tumour FDG uptake was qualitatively evaluated to determine the possibility of response monitoring with PET/CT and was quantitatively assessed using maximum standardized uptake values (SUV(max)). FDG uptake was compared with age, TNM stage, histology, hormone and human epidermal growth factor receptor 2 status, grade, Ki-67 and molecular subtype in univariable and multivariable analyses.

RESULTS

In 203 tumours (95 %) FDG uptake was considered sufficient for response monitoring. No subgroup of patients with consistently low tumour FDG uptake could be identified. In a univariable analysis, SUV(max) was significantly higher in patients with distant metastases at staging examination, non-lobular carcinomas, tumours with negative hormone receptors, triple negative tumours, grade 3 tumours, and in tumours with a high proliferation index (Ki-67 expression). After multiple linear regression analysis, triple negative and grade 3 tumours were significantly associated with a higher SUV(max).

CONCLUSION

Primary tumour FDG uptake in breast cancer patients scheduled for neoadjuvant chemotherapy is significantly higher in tumours with prognostically unfavourable characteristics. Based on tumour characteristics associated with low tumour FDG uptake, this study was unable to identify a subgroup of patients unlikely to benefit from pretreatment PET/CT.

Locoregional lymph node involvement on 18F-FDG PET/CT in breast cancer patients scheduled for neoadjuvant chemotherapy

The optimal method for locoregional staging in patients treated with neoadjuvant chemotherapy (NAC), usually ultrasound (US) and pre- or post-chemotherapy sentinel lymph node biopsy (SLNB), remains subject of debate. The aim of this study was to assess the value of 18F-FDG PET/CT for detecting locoregional lymph node metastases in primary breast cancer patients scheduled for NAC. 311 breast cancer patients, scheduled for NAC, underwent PET/CT of the thorax in prone position with hanging breasts. A panel of four experienced reviewers examined PET/CT images, blinded for other diagnostic procedures. FDG uptake in locoregional nodes was determined qualitatively using a 4-point scale (0 = negative, 1 = questionable, 2 = moderately intense, and 3 = very intense). Results were compared with pathology obtained by US-guided fine needle aspiration or SLNB prior to NAC. All FDG-avid extra-axillary nodes were considered metastatic, based on the previously reported high positive predictive value of the technique. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of FDG-avid nodes for the detection of axillary metastases (score 2 or 3) were 82, 92, 98, 53, and 84 %, respectively. Of 28 patients with questionable axillary FDG uptake (score 1), 23 (82 %) were node-positive. Occult lymph node metastases in the internal mammary chain and periclavicular area were detected in 26 (8 %) and 32 (10 %) patients, respectively, resulting in changed regional radiotherapy planning in 50 (16 %) patients. In breast cancer patients scheduled for NAC, PET/CT renders pre-chemotherapy SLNB unnecessary in case of an FDG-avid axillary node, enables axillary response monitoring during or after NAC, and leads to changes in radiotherapy for a substantial number of patients because of detection of occult N3-disease. Based on these results, we recommend a PET/CT as a standard staging procedure in breast cancer patients scheduled for NAC.

Molecular Imaging in Breast Cancer: From Whole-Body PET/CT to Dedicated Breast PET

Positron emission tomography (PET), with or without integrated computed tomography (CT), using 18F-fluorodeoxyglucose (FDG) is based on the principle of elevated glucose metabolism in malignant tumors, and its use in breast cancer patients is frequently being investigated. It has been shown useful for classification, staging, and response monitoring, both in primary and recurrent disease. However, because of the partial volume effect and limited resolution of most whole-body PET scanners, sensitivity for the visualization of small tumors is generally low. To improve the detection and quantification of primary breast tumors with FDG PET, several dedicated breast PET devices have been developed. In this nonsystematic review, we shortly summarize the value of whole-body PET/CT in breast cancer and provide an overview of currently available dedicated breast PETs.

Monitoring the progression of metastatic breast cancer on nanoporous silica chips

Breast cancer accounted for 15 per cent of total cancer deaths in female patients in 2010. Although significant progress has been made in treating early-stage breast cancer patients, there is still no effective therapy targeting late-stage metastatic breast cancers except for the conventional chemotherapy interventions. Until effective therapy for later-stage cancers emerges, the identification of biomarkers for the early detection of tumour metastasis continues to hold the key to successful management of breast cancer therapy. Our study concentrated on the low molecular weight (LMW) region of the serum protein and the information it contains for identifying biomarkers that could reflect the ongoing physiological state of all tissues. Owing to technical difficulties in harvesting LMW species, studying these proteins/peptides has been challenging until now. In our study, we have recently developed nanoporous chip-based technologies to separate small proteins/peptides from the large proteins in serum. We used nanoporous silica chips, with a highly periodic nanostructure and uniform pore size distribution, to isolate LMW proteins and peptides from the serum of nude mice with MDA-MB-231 human breast cancer lung metastasis. By matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and biostatistical analysis, we were able to identify protein signatures unique to different stages of cancer development. The approach and results reported in this study possess a significant potential for the discovery of proteomic biomarkers that may significantly enhance personalized medicine targeted at metastatic breast cancer.

Advances in molecular imaging for breast cancer detection and characterization

Advances in our ability to assay molecular processes, including gene expression, protein expression, and molecular and cellular biochemistry, have fueled advances in our understanding of breast cancer biology and have led to the identification of new treatments for patients with breast cancer. The ability to measure biologic processes without perturbing them in vivo allows the opportunity to better characterize tumor biology and to assess how biologic and cytotoxic therapies alter critical pathways of tumor response and resistance. By accurately characterizing tumor properties and biologic processes, molecular imaging plays an increasing role in breast cancer science, clinical care in diagnosis and staging, assessment of therapeutic targets, and evaluation of responses to therapies. This review describes the current role and potential of molecular imaging modalities for detection and characterization of breast cancer and focuses primarily on radionuclide-based methods.

[Modern diagnostics in breast cancer: nuclear medicine techniques]

The authors discuss the role of nuclear medicine techniques in the modern diagnostics of breast cancer, including the methods currently used in Hungary and the future possibilities.

Early metabolic response using FDG PET/CT and molecular phenotypes of breast cancer treated with neoadjuvant chemotherapy

BACKGROUND

This study was aimed 1) to investigate the predictive value of FDG PET/CT (fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography) for histopathologic response and 2) to explore the results of FDG PET/CT by molecular phenotypes of breast cancer patients who received neoadjuvant chemotherapy.

METHODS

Seventy-eight stage II or III breast cancer patients who received neoadjuvant docetaxel/doxorubicin chemotherapy were enrolled in this study. FDG PET/CTs were acquired before chemotherapy and after the first cycle of chemotherapy for evaluating early metabolic response.

RESULTS

The mean pre- and post-chemotherapy standard uptake value (SUV) were 7.5 and 3.9, respectively. The early metabolic response provided by FDG PET/CT after one cycle of neoadjuvant chemotherapy was correlated with the histopathologic response after completion of neoadjuvant chemotherapy (P = 0.002). Sensitivity and negative predictive value were 85.7% and 95.1%, respectively. The estrogen receptor negative phenotype had a higher pre-chemotherapy SUV (8.6 vs. 6.4, P = 0.047) and percent change in SUV (48% vs. 30%, P = 0.038). In triple negative breast cancer (TNBC), the pre-chemotherapy SUV was higher than in non-TNBC (9.8 vs. 6.4, P = 0.008).

CONCLUSIONS

The early metabolic response using FDG PET/CT could have a predictive value for the assessment of histopathologic non-response of stage II/III breast cancer treated with neoadjuvant chemotherapy. Our findings suggest that the initial SUV and the decline in SUV differed based on the molecular phenotype.

18F-FDG PET/CT as a staging procedure in primary stage II and III breast cancer: comparison with conventional imaging techniques

The aim of the present study was to investigate if 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) outperforms conventional imaging techniques for excluding distant metastases prior to neoadjuvant chemotherapy (NAC) treatment in patients with stage II and III breast cancer. Second, we assessed the clinical importance of false positive findings. One hundred and fifty four patients with stage II or III breast cancer, scheduled to receive NAC, underwent an 18F-FDG PET/CT scan and conventional imaging, consisting of bone scintigraphy, ultrasound of the liver, and chest radiography. Suspect additional lesions at staging examination were confirmed by biopsy and histopathology and/or additional imaging. Metastases that were detected within 6 months after the PET/CT scan were considered evidence of occult metastasis, missed by staging examination. Forty-two additional distant lesions were seen in 25 patients with PET/CT and could be confirmed in 20 (13%) of 154 patients. PET/CT was false positive for 8 additional lesions (19%) and misclassified the presence of metastatic disease in 5 (3%) of 154 patients. In 16 (80%) of 20 patients, additional lesions were exclusively seen with PET/CT, leading to a change in treatment in 13 (8%) of 154 patients. In 129 patients with a negative staging PET/CT, no metastases developed during the follow-up of 9.0 months. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of PET/CT in the detection of additional distant lesions in patients with stage II or III breast cancer are 100, 96, 80, 100, and 97%, respectively. FDG PET/CT is superior to conventional imaging techniques in the detection of distant metastases in patients with untreated stage II or III breast cancer and is associated with a low false positive rate. PET/CT may be of additional value in the staging of breast cancer prior to NAC.

FDG-PET/CT in the staging of local/regional metastases in breast cancer

Breast cancer is the commonest female malignancy in the Western world and the most reliable predictor for survival is axillary lymph node metastases. Conventional staging techniques employed in breast cancer include mammography, ultrasonography, isotope bone scanning, sentinel lymph node biopsy, axillary lymph node dissection and magnetic resonance imaging. More recently FDG-PET and FDG-PET/CT have been used to complement the above methods. This review assesses the role of FDG-PET/CT in axillary staging in patients with primary breast cancer. A PubMed search was conducted and all articles containing relevant or new information were included. Relevant studies examined identified that FDG-PET/CT has a sensitivity of 60% and a specificity of 97% in detecting lymphatic metastasis. Although positive axillary FDG-PET/CT is a good predictor of axillary disease and correlates well with SLNB, the relatively poor sensitivity (60%) must be considered for treatment planning.

FDG-PET/CT compared with conventional imaging in the detection of distant metastases of primary breast cancer

PURPOSE

Evidence from studies with small numbers of patients indicates that (18)F-fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT) accurately detects distant metastases in the staging of primary breast cancer. We compared the sensitivity and specificity of PET/CT and conventional imaging (CT, ultrasonography, radiography, and skeletal scintigraphy) for the detection of distant metastases in patients with primary breast cancer.

PATIENTS AND METHODS

We performed a retrospective review that identified 225 patients with primary breast cancer seen from January 2000 to September 2009 for whom PET/CT data were available for review. Imaging findings were compared with findings on biopsy, subsequent imaging, or clinical follow-up. Sensitivity and specificity in the detection of distant metastases were calculated for PET/CT and conventional imaging. Fisher's exact tests were used to test the differences in sensitivity and specificity between PET/CT and conventional imaging.

RESULTS

The mean patient age at diagnosis was 53.4 years (range, 23-84 years). The sensitivity and specificity in the detection of distant metastases were 97.4% and 91.2%, respectively, for PET/CT and 85.9% and 67.3%, respectively, for conventional imaging. The sensitivity and specificity of PET/CT were significantly higher than those of conventional imaging (p = .009 and p < .001, respectively). Eleven cases of distant metastases detected by PET/CT were clinically occult and not evident on conventional imaging.

CONCLUSION

PET/CT has higher sensitivity and specificity than conventional imaging in the detection of distant metastases of breast cancer. A prospective study is needed to determine whether PET/CT could replace conventional imaging to detect distant metastases in patients with primary breast cancer.

18F-fluorodeoxy-glucose positron emission tomography marks MYC-overexpressing human basal-like breast cancers

In contrast to normal cells, cancer cells avidly take up glucose and metabolize it to lactate even when oxygen is abundant, a phenomenon referred to as the Warburg effect. This fundamental alteration in glucose metabolism in cancer cells enables their specific detection by positron emission tomography (PET) following i.v. injection of the glucose analogue (18)F-fluorodeoxy-glucose ((18)FDG). However, this useful imaging technique is limited by the fact that not all cancers avidly take up FDG. To identify molecular determinants of (18)FDG retention, we interrogated the transcriptomes of human-cancer cell lines and primary tumors for metabolic pathways associated with (18)FDG radiotracer uptake. From ninety-five metabolic pathways that were interrogated, the glycolysis, and several glycolysis-related pathways (pentose phosphate, carbon fixation, aminoacyl-tRNA biosynthesis, one-carbon-pool by folate) showed the greatest transcriptional enrichment. This "FDG signature" predicted FDG uptake in breast cancer cell lines and overlapped with established gene expression signatures for the "basal-like" breast cancer subtype and MYC-induced tumorigenesis in mice. Human breast cancers with nuclear MYC staining and high RNA expression of MYC target genes showed high (18)FDG-PET uptake (P < 0.005). Presence of the FDG signature was similarly associated with MYC gene copy gain, increased MYC transcript levels, and elevated expression of metabolic MYC target genes in a human breast cancer genomic dataset. Together, our findings link clinical observations of glucose uptake with a pathologic and molecular subtype of human breast cancer. Furthermore, they suggest related approaches to derive molecular determinants of radiotracer retention for other PET-imaging probes.

Detection of isolated ipsilateral regional lymph node recurrences by F18-fluorodeoxyglucose positron emission tomography-CT in follow-up of postoperative breast cancer patients

Imaging diagnostic methods except for mammograms are not recommended for follow-up of postoperative breast cancer patients in order to detect small recurrences because of the poor survival improvement in earlier randomized trials. However, the use of new imaging modalities may improve survival by detection of small isolated regional lymph node recurrences which are potentially curable. Between April 2006 and December 2008, we used PET-CT to find small recurrences in follow-up of 1,907 postoperative breast cancer patients. A total of 3,280 PET-CT imagings were performed. The median age at PET-CT imaging was 58 years, with a median 48-month interval from definitive surgery to the PET-CT imaging. Twenty-two patients were found to have isolated ipsilateral regional recurrences only by PET-CT (axillary node recurrences in 6, infraclavicular node recurrences in 5, supraclavicular node recurrences in 6, and parasternal node recurrences in 5). All of those recurrences were missed by palpation or were nonpalpable. The pathological lymph node status at the definitive surgery for the primary breast cancer of 22 patients with the isolated ipsilateral regional lymph node recurrences was positive in 17 patients. If patients are limited to those who had pathologically positive node(s) at definitive surgery, the incidence of patients with isolated regional lymph node recurrences found only by PET-CT would be 2.6% (17/663 patients). Seventeen other asymptomatic cancers including contralateral breast cancers were found only by PET-CT. Early detection of isolated loco-regional recurrences of breast cancer is suggested to result in improved survival. Therefore, the use of PET-CT in follow-up of postoperative node-positive breast cancer patients may improve their survival because of early detection of isolated regional lymph node recurrences which are still potentially curable, and screening of other asymptomatic cancers.

Circulating tumor cells in breast cancer: a tool whose time has come of age

Circulating tumor cells (CTCs) are isolated tumor cells disseminated from the site of disease in metastatic and/or primary cancers, including breast cancer, that can be identified and measured in the peripheral blood of patients. As recent technical advances have rendered it easier to reproducibly and repeatedly sample this population of cells with a high degree of accuracy, these cells represent an attractive surrogate marker of the site of disease. Currently, CTCs are being integrated into clinical trial design as a surrogate for phenotypic and genotypic markers in correlation with development of molecularly targeted therapies. As CTCs play a crucial role in tumor dissemination, translational research is implicating CTCs in several biological processes, including epithelial to mesenchymal transition. In this mini-review, we review CTCs in metastatic breast cancer, and discuss their clinical utility for assessing prognosis and monitoring response to therapy. We will also introduce their utility in pharmacodynamic monitoring for rational selection of molecularly targeted therapies and briefly address how they can help elucidate the biology of cancer metastasis.

Positron emission tomography (PET) for assessment of axillary lymph node status in early breast cancer: A systematic review and meta-analysis

PURPOSE

Sentinel lymph node biopsy (SLNB) and axillary lymph node dissection (ALND) are used to assess axillary nodal status in breast cancer, but are invasive procedures associated with morbidity, including lymphoedema. This systematic review evaluates the diagnostic accuracy of positron emission tomography (PET), with or without computed tomography (CT), for assessment of axillary nodes in early breast cancer.

METHODS

Eleven databases including MEDLINE, EMBASE and the Cochrane Library, plus research registers and conference proceedings, were searched in April 2009. Study quality was assessed using the QUality Assessment of Diagnostic Accuracy Studies (QUADAS) checklist. Sensitivity and specificity were meta-analysed using a bivariate random effects approach.

RESULTS

Across 26 studies evaluating PET or PET/CT (n = 2591 patients), mean sensitivity was 63% (95% CI: 52-74%; range 20-100%) and mean specificity 94% (95% CI: 91-96%; range 75-100%). Across 7 studies of PET/CT (n = 862), mean sensitivity was 56% (95% CI: 44-67%) and mean specificity 96% (90-99%). Across 19 studies of PET-only (n = 1729), mean sensitivity was 66% (50-79%) and mean specificity 93% (89-96%). Mean sensitivity was 11% (5-22%) for micrometastases (≤2 mm; five studies; n = 63), and 57% (47-66%) for macrometastases (>2 mm; four studies; n = 111).

CONCLUSIONS

PET had lower sensitivity and specificity than SLNB. Therefore, replacing SLNB with PET would avoid the adverse effects of SLNB, but lead to more false negative patients at risk of recurrence and more false positive patients undergoing unnecessary ALND. The present evidence does not support the routine use of PET or PET-CT for the assessment of the clinically negative axilla.

CT assessment of breast cancer for pathological involvement of four or more axillary nodes

BACKGROUND

To predict the likelihood of ≥4 pathologically positive axillary nodes in breast cancer patients by computed tomography (CT) before neoadjuvant chemotherapy (NAC).

METHODS

Inclusion criteria for the 97 patients reviewed were lymph nodes (LNs) pathologically proved positive with standard level I-II axillary dissection, contrast-enhanced CT was performed before surgery, contralateral breast cancer was not present, and NAC was not given before surgery. The size, number, and level of both ipsilateral and contralateral axillary LNs were studied by contrast-enhanced high-resolution CT for pathologically positive LNs in breast cancer patients.

RESULTS

Level III LN was only detected in ipsilateral axilla of patients with ≥4 pathologically involved nodes. The number of ipsilateral level I-II LNs is the only factor significantly related to the pathological involvement of ≥4 axillary nodes. Increasing numbers of contralateral level I-II LNs are significantly related to increasing numbers of ipsilateral level I-II LNs. For the criterion of maximal LN size ≥5 mm, if contralateral level I-II LNs were negative and the cutoff points for ipsilateral level I-II LNs were 0-2 and ≥3, the sensitivity and specificity for ≥4 pathologically involved nodes would be 84.6 and 73.3%. If contralateral I-II LNs were positive, the negative predictive value was 80.0%.

CONCLUSION

Level III LN detection in ipsilateral axilla and the number of level I-II LNs in bilateral axilla will be helpful to predict ≥4 pathologically positive axillary nodes.