18fluorodeoxyglucose positron emission tomography to detect mediastinal or internal mammary metastases in breast cancer

Detectability of Al 18 F-NOTA-HER2-BCH PET for Nodal Metastases in Patients With HER2-Positive Breast Cancer

PURPOSE

The aim of this study was to compare Al 18 F-NOTA-HER2-BCH and 18 F-FDG for detecting nodal metastases in patients with HER2-positive breast cancer on PET/CT.

PATIENTS AND METHODS

In this retrospective study, 62 participants with HER2-positive breast cancer underwent both Al 18 F-NOTA-HER2-BCH and 18 F-FDG PET/CT. Participants were pathologically confirmed as HER2-positive (IHC 3+ or IHC 2+ with gene amplification on FISH). Three independent readers visually assessed uptake of tracers on imaging. Furthermore, the diagnostic accuracy of nodal metastases was assessed using c-statistics. The lesion uptakes were quantified by SUV max and target-to-background ratio (TBR) and compared using the general linear mixed model.

RESULTS

The findings showed nodal metastases in 33 (53%) participants, including 45% only with regional nodal metastasis and 55% with nonregional nodal metastasis. On per-patient level, the sensitivity and specificity of Al 18 F-NOTA-HER2-BCH and 18 F-FDG based on the majority reads were 0.97, 0.97, and 0.85, 0.77, respectively. Five participants were visualized only on Al 18 F-NOTA-HER2-BCH. Seven participants with high uptake only on 18 F-FDG PET/CT were confirmed to be inflammatory uptake by pathological results and later imaging follow-up. On per-lesion level, Al 18 F-NOTA-HER2-BCH PET/CT detected more axillary (98.8% vs 70.2%), extra-axillary (100% vs 61.7%), and nonregional (99.1% vs 67.0%) lymph nodal metastases than 18 F-FDG PET/CT. Additionally, Al 18 F-NOTA-HER2-BCH PET/CT detected more nodal metastases small than 10 mm than 18 F-FDG PET/CT (198 vs 125, 99.5% vs 62.8%). The median SUV max and TBR of regional or nonregional nodal metastases at Al 18 F-NOTA-HER2-BCH were all higher than those on 18 F-FDG (range of median SUV max , 8.0-11.4 vs 2.3-5.6; P range, <0.001-0.007; range of median TBR, 7.3-16.3 vs 2.9-5.3; P range, <0.001). No adverse reactions related to imaging agents were observed in all participants.

CONCLUSIONS

Al 18 F-NOTA-HER2-BCH PET/CT detected more regional and nonregional lymph nodal metastases in patients with HER2-positive breast cancer than on 18 F-FDG PET/CT, especially for lesions small than 10 mm.

The role of 18F-FDG PET/CT in detecting synchronous regional and distant metastatic disease in patients with an in-breast tumour recurrence

BACKGROUND

In line with the trend towards minimally invasive, patient-tailored treatment, a selected group of patients with an in-breast tumour recurrence (IBTR) is treated by repeat breast-conserving treatment (BCT). To select eligible patients for repeat BCT, a reliable pre-operative work-up is essential. This study reports on the role of 18F-FDG PET/CT in detecting synchronous regional and distant metastases in patients with IBTR.

PATIENTS AND METHODS

A nation-wide data query was sent out to all Dutch hospitals offering breast cancer treatment. Breast cancer surgeons from 34 hospitals participated, filling electronic case report forms (eCRFs) on 549 patients treated for IBTR from 2016 to 2017.

RESULTS

Of the 549 included patients, 297 were screened using 18F-FDG PET/CT for the presence of distant metastases. Forty of them (13.5 %) presented with synchronous distant metastatic disease. In 168 clinically node-negative patients who underwent 18F-FDG PET/CT, a suspect regional lymph node was found in 18 (10.7 %). Final pathology of these lymph nodes yielded a positive lymph node in 12 patients (7.1 %). Positive predictive value (PPV) of 18F-FDG PET/CT in clinically node-negative patients was 66.7 % and negative predictive value (NPV) was 85.3 %.

CONCLUSION

The clinically relevant percentage of synchronous distant metastatic disease justifies the use of 18F-FDG PET/CT in the workup of patients with an IBTR. Furthermore, 18F-FDG PET/CT can assist in detecting regional axillary lymph node metastases, but requires histopathological confirmation given the moderate PPV, before clinical decisions can be made.

PET Imaging of Breast Cancer: Current Applications and Future Directions

As molecular imaging use expands for patients with breast cancer, it is important for breast radiologists to have a basic understanding of molecular imaging, including PET. Although breast radiologists may not directly interpret such studies, basic knowledge of molecular imaging will enable the radiologist to better direct diagnostic workup of patients as well as discuss diagnostic imaging with the patient and other treating physicians. Several new tracers are now available to complement imaging glucose metabolism with FDG. Because it provides a noninvasive assessment of disease status across the whole body, PET offers specific advantages over tissue-based assays. Paired with targeted therapy, molecular imaging has the potential to guide personalized treatment of breast cancer, including guiding dosing during drug trials as well as predicting and assessing clinical response. This review discusses the current established applications of FDG, which remains the most widely used PET radiotracer for malignancy, including breast cancer, and highlights potential areas for expanded use based on recent research. It also summarizes research to date on the U.S. Food and Drug Administration (FDA)-approved PET tracer 16α-18F-fluoro-17β-estradiol (FES), which targets ER, including the current guidelines from the Society of Nuclear Medicine and Molecular Imaging on the appropriate use of FES-PET/CT for breast cancer as well as areas of active investigation for other potential applications. Finally, the review highlights several of the most promising novel PET tracers that are poised for clinical translation in the near future.

The Role of MRI in Breast Cancer and Breast Conservation Therapy

Contrast-enhanced breast MRI has an established role in aiding in the detection, evaluation, and management of breast cancer. This article discusses MRI sequences, the clinical utility of MRI, and how MRI has been evaluated for use in breast radiotherapy treatment planning. We highlight the contribution of MRI in the decision-making regarding selecting appropriate candidates for breast conservation therapy and review the emerging role of MRI-guided breast radiotherapy.

Evolution of overall survival and receipt of new therapies by subtype among 20 446 metastatic breast cancer patients in the 2008-2017 ESME cohort

Background

Treatment strategies for metastatic breast cancer (MBC) have made great strides over the past 10 years. Real-world data allow us to evaluate the actual benefit of new treatments. ESME (Epidemio-Strategy-Medico-Economical)-MBC, a nationwide observational cohort (NCT03275311), gathers data of all consecutive MBC patients who initiated their treatment in 18 French Cancer Centres since 2008.

Patients and methods

We evaluated overall survival (OS) in the whole cohort (N = 20 446) and among subtypes: hormone receptor positive, human epidermal growth factor 2 negative (HR+/HER2−; N = 13 590), HER2+ (N = 3919), and triple-negative breast cancer (TNBC; N = 2937). We performed multivariable analyses including year of MBC diagnosis as one of the covariates, to assess the potential OS improvement over time, and we described exposure to newly released drugs at any time during MBC history by year of diagnosis (YOD).

Results

The median follow-up of the whole cohort was 65.5 months (95% CI 64.6-66.7). Year of metastatic diagnosis appears as a strong independent prognostic factor for OS [Year 2016 HR 0.89 (95% CI 0.82-0.97); P = 0.009, using 2008 as reference]. This effect is driven by the HER2+ subcohort, where it is dramatic [Year 2016 HR 0.52 (95% CI 0.42-0.66); P < 0.001, using 2008 as reference]. YOD had, however, no sustained impact on OS among patients with TNBC [Year 2016 HR 0.93 (95% CI 0.77-1.11); P = 0.41, using 2008 as reference] nor among those with HR+/HER2– MBC [Year 2016 HR 1.02 (95% CI 0.91-1.13); P = 0.41, using 2008 as reference]. While exposure to newly released anti-HER2 therapies appeared very high (e.g. >70% of patients received pertuzumab from 2016 onwards), use of everolimus or eribulin was recorded in less than one-third of HR+/HER2– and TNBC cohorts, respectively, whatever YOD.

Conclusion

OS has dramatically improved among HER2+ MBC patients, probably in association with the release of several major HER2-directed therapies, whose penetrance was high. This trend was not observed in the other subtypes, but the impact of CDK4/6 inhibitors cannot yet be assessed.

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OS of HER2+ MBC patients keeps improving over time [Year 2016 HR 0.52 (95% CI 0.42-0.66); P < 0.001, using 2008 as reference].

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This effect seems timely related to the release of drugs demonstrated to improve survival in clinical trials.

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OS gains observed in real life among HER2+ MBC patients are at least equivalent to those observed in clinical trials.

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YOD had no sustained impact on OS among patients with TNBC and luminal MBC.

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The impact of CDK4/6 inhibitors cannot yet be assessed in this cohort.

Evaluation of internal mammary lymph node biopsy during microsurgical breast reconstruction: An analysis of 230 consecutive patients

INTRODUCTION

Clinical significance of internal mammary (IM) lymph node biopsy during microvascular free flap breast reconstruction remains controversial. Some microsurgeons may choose to biopsy an IM lymph node during routine IM vessel dissection. The authors reviewed the results of IM lymph node biopsy during autologous breast reconstruction.

METHODS

A retrospective chart review of patients who underwent autologous breast reconstruction during a seven-year period (January 2010 to January 2017) was performed. Patient demographic data, disease staging, flap details, pathology reports, and adjuvant treatment were evaluated.

RESULTS

A total of 230 patients with a mean age of 52.1 (SD 9.3) underwent IM lymph node biopsy (n = 297). Single IM lymph node was removed in 169 patients, 2 nodes were removed in 56 patients, 3 nodes in 4 patients, and 4 nodes in a single patient. Histopathologic analysis demonstrated presence of IM lymph node metastasis in 16 patients (7.0%). Thirteen patients were found to have metastatic IM lymph nodes in the setting of immediate reconstruction. Three patients were found to have metastatic IM lymph nodes in the setting of delayed. Five out of 16 patients (31.3%) had negative axillary sentinel lymph node biopsy and IM lymph nodes were the only site of nodal metastases. All five of these patients were upstaged accordingly and received adjuvant therapy based on the discussion at the multidisciplinary breast tumor conference.

CONCLUSIONS

Opportunistic internal mammary lymph node sampling during autologous breast reconstruction can be performed with minimal morbidity and has significant impact on the disease staging and adjuvant treatment.

The use of 18F-FDG positron emission tomography to detect mediastinal lymph nodes in metastatic breast cancer

BACKGROUND

To assess the predictive value of 18F-fluorodeoxyglucose positron-emission tomography (FDG-PET/CT) in detecting mediastinal lymph node metastasis with histopathologic verification in breast cancer (BC) patients.

MATERIALS AND METHODS

Between February 2012 and October 2019, 37 BC patients who underwent histopathological verification for FDG-PET positive mediastinal lymph nodes were retrospectively analyzed. Nine patients (24%) were screened before beginning treatment, while 27 (76%) were screened at the time of disease progression, an average of 39 months after completion of initial treatment.

RESULTS

The histopathologic diagnosis revealed lymph node metastasis from BC in 15 patients (40%) and benign disease in 22 patients (60%). The standardized uptake value (SUVmax) of mediastinal lymph nodes was significantly higher in patients with lymph node metastasis compared to those with benign histology (9.0 ± 3.5 vs. 5.9 ± 2.4; P = 0.007). The cut-off value of SUVmax after the ROC curve analysis for pathological lymph node metastasis was 6.4. Two of the 15 patients with mediastinal SUVmax ≤ 6.4 and 13 of the 22 patients with SUVmax > 6.4 had lymph node metastasis. Age and pathological findings were prognostic factors for overall survival in univariate analysis. The treatment decision was changed in 19 patients (51%) after mediastinoscopic evaluation of the entire cohort.

CONCLUSIONS

This is the first study to support the need for pathologic confirmation of a positive PET/CT result following evaluation of mediastinal lymph nodes for staging BC, either at initial diagnosis or at the time of progression. Treatment decisions were consequently altered for nearly half of the patients.

Imaging and Management of Internal Mammary Lymph Nodes

Internal mammary lymph nodes (IMLNs) account for approximately 10%-40% of the lymphatic drainage of the breast. Internal mammary lymph nodes measuring up to 10 mm are commonly seen on high-risk screening breast MRI examinations in patients without breast cancer and are considered benign if no other suspicious findings are present. Benign IMLNs demonstrate a fatty hilum, lobular or oval shape, and circumscribed margins without evidence of central necrosis, cortical thickening, or loss of fatty hilum. In patients with breast cancer, IMLN involvement can alter clinical stage and treatment planning. The incidence of IMLN metastases detected on US, CT, MRI, and PET-CT ranges from 10%-16%, with MRI and PET-CT demonstrating the highest sensitivities. Although there are no well-defined imaging criteria in the eighth edition of the American Joint Committee on Cancer Staging Manual for Breast Cancer, a long-axis measurement of ≥ 5 mm is suggested as a guideline to differentiate benign versus malignant IMLNs in patients with newly diagnosed breast cancer. Abnormal morphology such as loss of fatty hilum, irregular shape, and rounded appearance (which can be quantified by a short-axis/long-axis length ratio greater than 0.5) also raises suspicion for IMLN metastases. MRI and PET-CT have good sensitivity and specificity for the detection of IMLN metastases, but fluorodeoxyglucose avidity can be seen in both benign conditions and metastatic disease. US is helpful for staging, and US-guided fine-needle aspiration can be performed in cases of suspected IMLN metastasis. Management of suspicious IMLNs identified on imaging is typically with chemotherapy and radiation, as surgical excision does not provide survival benefit and is performed only in rare cases.

Breast-conserving surgery with or without irradiation in women with invasive ductal carcinoma of the breast receiving preoperative systemic therapy: A cohort study

Purpose

To investigate the outcomes of adjuvant whole breast radiation therapy (WBRT) in patients with invasive ductal carcinoma of the breast (breast IDC) receiving preoperative systemic therapy (PST) and breast-conserving surgery (BCS), and their prognostic factors, considering overall survival (OS), locoregional recurrence (LRR), distant metastasis (DM), and disease-free survival.

Patients and methods

Patients diagnosed as having breast IDC and receiving PST followed by BCS were recruited and categorized by treatment into non-breast radiation therapy [BRT] (control) and WBRT (case) groups, respectively. Cox regression analysis was used to calculate hazard ratios (HRs) and confidence intervals (CIs).

Results

Multivariate Cox regression analyses indicated that non-BRT, cN3, and pathologic residual tumor (ypT2–4) or nodal (ypN2–3) stages were poor prognostic factors for OS. The adjusted HRs (aHRs; 95% CIs) of the WBRT group to non-BRT group for all-cause mortality were 0.14 (0.03–0.81), 0.32 (0.16–0.64), 0.43 (0.23–0.79), 0.23 (0.13–0.42), 0.52 (0.20–1.33), and 0.34 (0.13–0.87) in the ypT0, ypT1, ypT2–4, ypN0, ypN1, and ypN2–3 stages, respectively. The aHRs (95% CIs) of the WBRT group to non-BRT group for all-cause mortality were 0.09 (0.00–4.07), 0.46 (0.26–0.83), 0.18 (0.06–0.51), 0.28 (0.06–1.34), 0.25 (0.10–0.63), 0.47 (0.23–0.88), and 0.32 in the cT0–1, cT2, cT3, cT4, cN0, cN1, and cN2–3 stages, respectively. The WBRT group exhibited significantly better LRR-free and DM-free survival than the non-BRT group, regardless of the clinical T or N stage or pathologic response after PST.

Conclusion

WBRT might lead to superior OS and LRR-free and DM-free survival compared with the non-BRT group, regardless of the initial clinical TN stage or pathologic response.

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Outcome patterns of adjuvant RT for patients with breast cancer receiving preoperative systemic therapy and breast-conserving surgery.

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Non-breast radiation therapy, cN3, pathologic residual tumor (ypT2–4), or nodal (ypN2–3) stages are poor prognostic factors for survival.

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The beneficial effects of RT are superior OS and LRR-free and DM-free survival compared with the non-RT group.

Progress and Future Trends in PET/CT and PET/MRI Molecular Imaging Approaches for Breast Cancer

Breast cancer is a major disease with high morbidity and mortality in women worldwide. Increased use of imaging biomarkers has been shown to add more information with clinical utility in the detection and evaluation of breast cancer. To date, numerous studies related to PET-based imaging in breast cancer have been published. Here, we review available studies on the clinical utility of different PET-based molecular imaging methods in breast cancer diagnosis, staging, distant-metastasis detection, therapeutic and prognostic prediction, and evaluation of therapeutic responses. For primary breast cancer, PET/MRI performed similarly to MRI but better than PET/CT. PET/CT and PET/MRI both have higher sensitivity than MRI in the detection of axillary and extra-axillary nodal metastases. For distant metastases, PET/CT has better performance in the detection of lung metastasis, while PET/MRI performs better in the liver and bone. Additionally, PET/CT is superior in terms of monitoring local recurrence. The progress in novel radiotracers and PET radiomics presents opportunities to reclassify tumors by combining their fine anatomical features with molecular characteristics and develop a beneficial pathway from bench to bedside to predict the treatment response and prognosis of breast cancer. However, further investigation is still needed before application of these modalities in clinical practice. In conclusion, PET-based imaging is not suitable for early-stage breast cancer, but it adds value in identifying regional nodal disease and distant metastases as an adjuvant to standard diagnostic imaging. Recent advances in imaging techniques would further widen the comprehensive and convergent applications of PET approaches in the clinical management of breast cancer.

PET/CT of breast cancer regional nodal recurrences: an evaluation of contouring atlases

BACKGROUND

To validate the Radiation Therapy Oncology Group (RTOG) and European Society for Radiotherapy and Oncology (ESTRO) breast cancer nodal clinical target volumes (CTVs) and to investigate the Radiotherapy Comparative Effectiveness Consortium (RADCOMP) Posterior Neck volume in relation to regional nodal recurrences (RNR).

METHODS

From a population-based database, 69 patients were identified who developed RNR after curative treatment for breast cancer. RNRs were detected with 18-fluorodeoxyglucose-positron emission tomography-computed tomography (PET/CT). All patients were treatment-naïve for RNR when imaged. The RTOG and ESTRO nodal CTVs and RADCOMP Posterior Neck volumes were contoured onto a template patient's CT. RNRs were contoured on each PET/CT and deformed onto the template patient's CT. Each RNR was represented by a 5 mm diameter epicentre, and categorized as 'inside', 'marginal' or 'outside' the CTV boundaries.

RESULTS

Sixty-nine patients with 226 nodes (median 2, range 1-11) were eligible for inclusion. Thirty patients had received adjuvant tangent and regional nodal radiotherapy, 16 tangent-only radiotherapy and 23 no adjuvant radiotherapy. For the RTOG CTVs, the RNR epicentres were 70% (158/226) inside, 4% (8/226) marginal and 27% (60/226) outside. They included the full extent of the RNR epicentres in 38% (26/69) of patients. Addition of the RADCOMP Posterior Neck volume increased complete RNR coverage to 48% (33/69) of patients. For the ESTRO CTVs, the RNR epicentres were 73% (165/226) inside, 2% (4/226) marginal and 25% (57/226) outside. They included the full extent of the RNR epicentres in 57% (39/69) of patients. Addition of the RADCOMP Posterior Neck volume increased complete RNR coverage to 70% (48/69) of patients.

CONCLUSIONS

The RTOG and ESTRO breast cancer nodal CTVs do not fully cover all potential areas of RNR, but the ESTRO nodal CTVs provided full coverage of all RNR epicentres in 19% more patients than the RTOG nodal CTVs. With addition of the RADCOMP Posterior Neck volume to the ESTRO CTVs, 70% of patients had full coverage of all RNR epicentres.

Evaluation of Diagnostic Accuracy and Impact of Preoperative Positron Emission Tomography/Computed Tomography in the Management of Early Operable Breast Cancers

AIM

Our aim of this study was to evaluate the diagnostic accuracy of staging positron emission tomography/computed tomography (PET/CT) in early breast cancers (EBCs) and to assess its impact on disease management.

PATIENTS AND METHODS

We retrospectively reviewed preoperative PET/CT scans of patients from January 2015 to December 2018 with Stage I/II, clinically T1-T2 N0-N1 breast cancers. The diagnostic performance of PET/CT for nodal (N) and distant metastases (M), its correlation with patient/tumor-specific factors, and its impact on disease management were analyzed using histopathology/clinical follow-up as standards of reference.

RESULTS

Of 158 patients evaluated, 14% of patients were Stage I (T1N0), 60% were Stage IIA (T1N1, T2N0), and 26% were Stage IIB (T2N1). Sensitivity, specificity, and the diagnostic accuracy of PET/CT for axillary staging were 76%, 97%, and 84% and for distant metastasis evaluation were 100%, 98%, and 99%, respectively. The diagnostic accuracy of PET/CT for axillary staging was lower for low-grade, T1 tumors, postmenopausal group, and luminal A pathological subtype (77%, 84%, 81%, and 73%, respectively) compared to high-grade, T2 tumors, premenopausal group, and nonluminal A subtype (88%, 88%, 94%, and 87%, respectively). Distant metastases were detected on PET/CT in overall 16% (n = 25) of the patients (9% in Stage IIA and 27% in Stage IIB). PET/CT also incidentally identified clinically occult internal mammary nodes in 5% (n = 8) and organ-confined synchronous second malignancies in 5% (n = 8) of the patients.

CONCLUSION

Preoperative PET/CT should be considered in all EBCs> 2 cm as it upstages the disease and alters management in about 24% of these patients. Given its high specificity for axillary staging PET/CT, patients with PET-positive axilla can be subjected to axillary dissection and those with PET-negative axilla to sentinel lymph node biopsy. The yield and diagnostic accuracy of PET/CT is less for low-grade tumors <2 cm and with luminal A subtype.

Incidence of internal mammary node in locally advanced breast cancer and its correlation with metastatic disease: a retrospective observational study

OBJECTIVE

To determine incidence of internal mammary nodes (IMN) at baseline CT of locally advanced breast cancer (LABC) and ascertain prognostic implication.

METHODS AND MATERIALS

Retrospective review of all LABC patients from 1 January 2012 through 31 December 2014 was performed after approval from institutional review board. CTs of 182 patients enrolled were reviewed by two radiologists independently, and IMNs were documented based on size, location and relation with location of breast primary. 3-year follow-up was analysed and incidence of metastases was calculated as overall incidence, incidence in patients with and without discernible IMN at baseline imaging. Results are presented as numbers and percentages. Differences in metastases of two groups were compared using χ2 test. 95% CI was calculated and p < 0.05 was considered significant.

RESULTS

77 of 182 had identifiable IMN (42.3% incidence). Majority of identifiable nodes were on ipsilateral side of primary (incidence 90.90%) with higher incidence in patients with upper-outer quadrant tumours (55.9%). Majority were seen in second intercostal space (44.4%). 36 (19.7%) developed distant metastases within 3 years of therapy. Of these, 21 (27.3%) had IMN as compared with 15 (14.3 %) without IMN on baseline imaging. Patients with identifiable IMN on baseline CT had significantly higher incidence of distant metastases (p = 0.0321).

CONCLUSION

Significant number LABC patients have identifiable IMN on baseline imaging with patients showing IMN on baseline CT showing significantly higher rate of metastatic disease following therapy.

ADVANCES IN KNOWLEDGE

Many LABC patients have identifiable IMNs on baseline imaging which show higher incidence of subsequent metastatic disease.

Screening for distant metastases in patients with ipsilateral breast tumor recurrence: the impact of different imaging modalities on distant recurrence-free interval

Purpose

In patients with ipsilateral breast tumor recurrence (IBTR), the detection of distant disease determines whether the intention of the treatment is curative or palliative. Therefore, adequate preoperative staging is imperative for optimal treatment planning. The aim of this study is to evaluate the impact of conventional imaging techniques, including chest X-ray and/or CT thorax-(abdomen), liver ultrasonography(US), and skeletal scintigraphy, on the distant recurrence-free interval (DRFI) in patients with IBTR, and to compare conventional imaging with ¹⁸F-FDG PET-CT or no imaging at all.

Methods

This study was exclusively based on the information available at time of diagnoses of IBTR. To adjust for differences in baseline characteristics between the three imaging groups, a propensity score (PS) weighted method was used.

Results

Of the 495 patients included in the study, 229 (46.3%) were staged with conventional imaging, 89 patients (19.8%) were staged with ¹⁸F-FDG PET-CT, and in 168 of the patients (33.9%) no imaging was used (N = 168). After a follow-up of approximately 5 years, 14.5% of all patients developed a distant recurrence as first event after IBTR. After adjusting for the PS weights, the Cox regression analyses showed that the different staging methods had no significant impact on the DRFI.

Conclusions

This study showed a wide variation in the use of imaging modalities for staging IBTR patients in the Netherlands. After using PS weighting, no statistically significant impact of the different imaging modalities on DRFI was shown. Based on these results, it is not possible to recommend staging for distant metastases using ¹⁸F-FDG PET-CT over conventional imaging techniques.

Electronic supplementary material

The online version of this article (10.1007/s10549-019-05205-z) contains supplementary material, which is available to authorized users.

Impacts of time interval on 18F-FDG uptake for PET/CT in normal organs: A systematic review

BACKGROUND

To perform a systematic review of the effect of time interval on 2-deoxy-2-[18F] fluoro-D-glucose (18F-FDG) uptake in normal organs.

METHODS

PubMed, EMBASE, Ovid, and Cochrane databases were searched to identity all potential eligible literature. The study characteristics and relevant data were extracted and analyzed. We adopted the effect size (ES) and the coefficient of determination (R) to best measure the magnitude of the relation between time interval and 18F-FDG uptake in normal organs.

RESULTS

Seven articles and 860 participants were included. The time interval on liver and mediastinal blood pool were relatively medium (R=0.01-0.03, ES = -0.57 and -0.60) but noticeable (R = 0.06, ES = -0.68 and -0.39), respectively. The uptake of 18F-FDG on cerebellum, spleen, bone marrow, muscle, bowel, and adipose remains to be verified as the rare studies. In addition, other factors such as body mass index and blood glucose level appeared to be important which also affect 18F-FDG uptake in normal organs.

CONCLUSION

The impact of time interval on SUVs in liver and mediastinal blood pool were relatively medium but clinically noticeable. More studies need to be done to solve the relation between the SUVs of other organs and time interval.

What, where and why: exploring fluorodeoxyglucose-PET's ability to localise and differentiate infection from cancer

PURPOSE OF REVIEW

To review the utility of FDG-PET imaging in detecting the cause of fever and infection in patients with cancer.

RECENT FINDINGS

FDG-PET has been shown to have high sensitivity and accuracy for causes of neutropenic fever, leading to higher diagnostic certainty in this group. Recent advances in pathogen-specific labelling in PET to identify Aspergillus spp. and Yersinia spp. infections in mice, as well as differentiating between Gram-positive, Gram-negative and mycobacterial infections are promising.

SUMMARY

Patients with cancer are vulnerable to infection and fever, and the causes of these are frequently unclear using conventional diagnostic methods leading to high morbidity and mortality, length of stay and costs of care. FDG-PET/CT, with its unique complementary functional and anatomical information as well as its whole-body imaging capability, has demonstrated use in detecting occult infection in immunocompromised patients, including invasive fungal and occult bacterial infections, as well as defining extent of infection. By demonstrating disease resolution following treatment and allowing earlier cessation of therapy, FDG-PET acts as a key tool for antimicrobial and antifungal stewardship. Limitations include at times poor differentiation between infection, malignancy and sterile inflammation, however, exciting new technologies specific to infectious pathogens may help alleviate that issue. Further prospective randomised research is needed to explore these benefits in a nonbiased fashion.

Ultrasound Imaging Technologies for Breast Cancer Detection and Management: A Review

Ultrasound imaging is a commonly used modality for breast cancer detection and diagnosis. In this review, we summarize ultrasound imaging technologies and their clinical applications for the management of breast cancer patients. The technologies include ultrasound elastography, contrast-enhanced ultrasound, 3-D ultrasound, automatic breast ultrasound and computer-aided detection of breast ultrasound. We summarize the study results seen in the literature and discuss their future directions. We also provide a review of ultrasound-guided, breast biopsy and the fusion of ultrasound with other imaging modalities, especially magnetic resonance imaging (MRI). For comparison, we also discuss the diagnostic performance of mammography, MRI, positron emission tomography and computed tomography for breast cancer diagnosis at the end of this review. New ultrasound imaging techniques, ultrasound-guided biopsy and the fusion of ultrasound with other modalities provide important tools for the management of breast patients.

Internal Thoracic Lymphadenopathy in Breast Cancer

The internal thoracic (IT) nodal basin is a first-echelon drainage pathway in the breast, accounting for up to a quarter of its lymphatic drainage, primarily from the deep structures of the breast. The presence of internal thoracic node (ITN) metastases upstages the breast cancer (BC) patient to a minimum of clinical stage III disease. Medial tumors, deep tumors, young age, axillary nodal metastases, tumors of a high nuclear grade, lymphovascular invasion, and triple-negative hormone receptor status are predisposing factors for ITN metastases from primary BC. It has been observed that medial tumors carry a worse prognosis than lateral tumors when all other factors are equal, indicating that understaging of ITN has a significant impact on patient outcomes. Despite the established prognostic significance of IT adenopathy in BC, this nodal basin is not routinely staged due to the difficulty in accessing it and due to the controversy regarding its management. Since the initial ITN studies in the 1960s, improvement in imaging techniques and the availability of minimally invasive biopsy techniques have fueled renewed interest in ITNs and their clinical significance in BC. Radiologists who image and diagnose BC can offer more accurate staging assessments by consistently evaluating the IT nodal chain in the BC patient. In this article, the authors discuss current knowledge of the ITNs in BC and review ITN anatomy. The imaging appearance of pathologic ITNs using various modalities, potential mimics of IT adenopathy, and image-guided sampling techniques are described. A succinct discussion of the clinical management of ITN-positive BC and its challenges is also included. ^© RSNA, 2017.

Impact of pathologic diagnosis of internal mammary lymph node metastasis in clinical N2b and N3b breast cancer patients

PURPOSE

To analyze the prognostic role of pathologic confirmation of internal mammary lymph nodes (IMNs) for breast cancer patients who received neoadjuvant chemotherapy.

METHODS

Of the patients who were treated with neoadjuvant chemotherapy, surgery, and radiation therapy between 2009 and 2013, 114 women had suspicious IMNs and FNAB was attempted. Clinical IMN metastasis was diagnosed by 18F-FDG PET/CT positivity or pathologic confirmation (N = 70). Patients were divided into the FNAB(+) or FNAB(-) IMN group.

RESULTS

The pathologic confirmation rate was 57% (40 of 70 patients). Rates were 74% in US-positive, 70% in MRI-positive, and 55% in PET-positive patients. Nodal stage was cN2b (6%) or cN3b (94%). Five-year progression-free survival (PFS) was significantly worse in patients with FNAB(+) IMN metastasis than FNAB(-) IMN metastasis (61% vs. 87%, P = 0.03). FNAB(+) IMN patients showed worse distant metastasis and regional recurrence-free survival without statistical significance (69% vs. 86%, P = 0.06, and 81% vs. 96%, P = 0.06). With median follow-up of 50.5 months (13.0-97.0 months), overall survival at 5 years was 77%, and PFS was 72%.

CONCLUSIONS

Patients with FNAB-proven IMN metastasis had worse treatment outcomes compared to patients with clinically diagnosed IMN metastasis in cN2b/N3b breast cancer.

Comparative diagnostic accuracy of 18F-FDG PET/CT for breast cancer recurrence

In the last decades, in addition to conventional imaging techniques and magnetic resonance imaging (MRI), ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) has been shown to be relevant in the detection and management of breast cancer recurrence in doubtful cases in selected groups of patients. While there are no conclusive data indicating that imaging tests, including FDG PET/CT, produce a survival benefit in asymptomatic patients, FDG PET/CT can be useful for identifying the site of relapse when traditional imaging methods are equivocal or conflicting and for identifying or confirming isolated loco-regional relapse or isolated metastatic lesions. The present narrative review deals with the potential role of FDG PET in these clinical settings by comparing its accuracy and impact with conventional imaging modalities such as CT, ultrasound, bone scan, ¹⁸F-sodium fluoride PET/CT (¹⁸F-NaF PET/CT) as well as MRI. Patient-focused perspectives in terms of patients' satisfaction and acceptability are also discussed.

Value of fourth and subsequent post-therapy follow-up 18F-FDG PET/CT scans in patients with breast cancer

OBJECTIVE

To evaluate the accuracy and value of the fourth and subsequent post-therapy follow-up fluorine-18 fluorodeoxyglucose (F-FDG) PET/computed tomography (CT) scans in the clinical assessment of breast cancer patients.

MATERIALS AND METHODS

Ninety-two female patients, with a total of 426 fourth and subsequent follow-up PET/CT scans, were retrospectively included. Patients were followed for a median of 23.7 months (range, 0.7-124.4) from the fourth follow-up PET/CT. The diagnostic accuracy of PET/CT, its impact on clinical assessment, patients' management, and survival outcome were established.

RESULT

Of the 426 follow-up PET/CT scans, 264 (62%) were interpreted as positive and 162 (38%) were interpreted as negative. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of the fourth and subsequent follow-up PET/CT scans were 97.7, 98.1, 98.8, 96.3, and 97.9%, respectively. Fourth and subsequent follow-up PET/CT were useful in excluding a tumor in 13.4% (39/292) of patients with a clinical suspicion of recurrence and identifying suspected recurrence in 10.5% (14/134) of patients without previous clinical suspicion. A change in management was noted in 6.7% (9/134) of scan times when the scans were performed without previous clinical suspicion of recurrence or therapy response and was 27.7% (81/292) when the scans were performed with clinical suspicion. Overall survival differed significantly between patients with all negative follow-up scans (n=23) and those who had at least one positive follow-up scan (n=69) (hazard ratio of 4.65, P<0.001).

CONCLUSION

The fourth and subsequent PET/CT scans performed after the completion of primary treatment led to a change in management in 27.7% of patients when the scans were performed with clinical suspicion and only in 6.7% of patients when performed without clinical suspicion or context.

Initial Fludeoxyglucose (18F) Positron Emission Tomography-Computed Tomography (FDG-PET/CT) Imaging of Breast Cancer - Correlations with the Primary Tumour and Locoregional Metastases

BACKROUND

We aimed to evaluate initial PET/CT features of primary tumour and locoregional metastatic lymph nodes (LNs) in breast cancer and to look for potential relationships between several parameters from PET/CT.

MATERIAL/METHODS

Twenty-three women (mean age; 48.66±12.23 years) with a diagnosis of primary invasive ductal carcinoma were included. They underwent PET/CT imaging for the initial tumour staging and had no evidence of distant metastates. Patients were divided into two groups. The LABC (locally advanced breast cancer) group included 17 patients with ipsilateral axillary lymph node (LN) metastases. The Non-LABC group consisted of six patients without LN metastases. PET/CT parameters including tumour size, axillary LN size, SUV_max of ipsilateral axillary LNs (SUV_max-LN), SUV_max of primary tumour (SUV_max-T) and NT ratios (SUV_max-LN/SUV_max-T) were compared between the groups. Correlations between the above-mentioned PET/CT parameters in the LABC group as well as the correlation between tumour size and SUV_max-T within each group were evaluated statistically.

RESULTS

The mean values of the initial PET/CT parameters in the LABC group were significantly higher than those of the non-LABC group (p<0.05). The correlation between tumour size and SUV_max-T value within both LABC and non-LABC groups was statistically significant (p<0.05). In the LABC group, the correlations between the size and SUV_max-LN values of metastatic axillary LNs, between tumour size and metastatic axillary LN size, between SUV_max-T values and metastatic axillary LN size, between SUV_max-T and SUV_max-LN values, and between tumour size and SUV_max-LN values were all significant (p<0.05).

CONCLUSIONS

We found significant correlations between PET/CT parameters of the primary tumour and those of metastatic axillary LNs. Patients with LN metastases had relatively larger primary tumours and higher SUV_max values.

Management of the Regional Lymph Nodes in Early-Stage Breast Cancer

The management of regional nodes in early-stage invasive breast cancer continues to evolve. Improved systemic therapy has contributed to better local regional control, and at the same time it has drawn more attention to its importance. Axillary dissections have decreased, in part because of the increased efficacy of systemic therapy, and also because adjuvant therapy decisions are increasingly driven by biologic characterization of the tumor rather than pathologic nodal information. The trend toward less axillary surgery and a shift toward increased reliance on systemic and radiation therapy to address nodal disease has created interesting questions that were subsequently addressed in recent trials. We review the controversies in regional nodal management, the benefits of current treatment paradigms, the balance between less surgery and more radiation, and the potential tradeoffs vs toxicity.

Breast Magnetic Resonance Imaging for Assessment of Internal Mammary Lymph Node Status in Breast Cancer

Purpose

The purpose of this study was to assess magnetic resonance imaging (MRI) features of malignant internal mammary lymph nodes (IMLNs) and benign IMLNs in breast cancer patients.

Methods

From 2009 to 2014, the records of 85 patients with IMLNs were archived using MRI report data; 26 patients with small size (long axis diameter <5 mm) nodes were subsequently excluded. The current study evaluated internal mammary lymph nodes in 59 patients who underwent breast MRI for breast cancer staging and for posttherapy follow-up. All MRI findings were retrospectively evaluated. Malignancy was determined based on pathologic examination and positron emission tomography computed tomography findings. Independent t-tests, Mann-Whitney U tests, chi-square tests, and receiver operating characteristics (ROC) curve analysis were used.

Results

Among MRI features, there were statistically significant differences between benign and malignant IMLN groups, in short axis length (3.6±1.3 vs. 8.2±2.9 mm, respectively), long axis length (8.1±2.4 vs. 14.5±4.8 mm, respectively), short/long axis ratio (0.45±0.10 vs. 0.59±0.17, respectively), absent fatty hilum (mean, 0% vs. 95%, respectively), and restricted diffusion (15.8% vs. 85.0%, respectively) (p<0.050). Multiplicity and location of intercostal spaces was not different between the two groups. Short axis length was the most discriminative variable for predicting metastatic nodes (area under the ROC curve, 0.951; threshold, 4 mm; sensitivity, 92.5%; specificity, 84.2%).

Conclusion

Conventional MRI and diffusion-weighted MRI are helpful to detect metastasis of internal mammary lymph nodes in breast cancer.

Imaging fungal infections in children

Fungal infections in children rarely occur, but continue to have a high morbidity and mortality despite the development of newer antifungal agents. It is essential for these infections to be diagnosed at the earliest possible stage so appropriate treatment can be initiated promptly. The addition of high-resolution computer tomography (HR CT) has helped in early diagnosis making; however, it lacks both sensitivity and specificity. Metabolic changes precede anatomical changes and hybrid imaging with positron emission tomography (PET) integrated with imaging modalities with high anatomical resolution such as CT or magnetic resonance imaging (MRI) is likely to detect these infections at an earlier stage with higher diagnostic accuracy rates. Several authors presented papers highlighting the advantages of PET/CT in imaging fungal infections. These papers, however, usually involve a limited number of patients and mostly adults. Fungal infections behave different in children than in adults, since there are differences in epidemiology, imaging findings, and response to treatment with antifungal drugs. This paper reviews the literature and explores the use of hybrid imaging for diagnosis and therapy decision making in children with fungal infections.

Detection of Internal Mammary Adenopathy in Patients With Breast Cancer by PET/CT and MRI

OBJECTIVE

The purpose of this study was to assess the prevalence of internal mammary node (IMN) adenopathy in patients with breast cancer and compare breast MRI and PET/CT for detection of IMN adenopathy.

MATERIALS AND METHODS

This retrospective study included 90 women who underwent MRI and PET/CT before neoadjuvant chemotherapy for clinical stage IIA through IIIA disease. MRI and PET/CT examinations were read independently by two readers trained in breast imaging and nuclear medicine. All patients underwent follow-up MRI at the end of chemotherapy, and 10 with hypermetabolic IMNs underwent follow-up PET/CT. Histology was not obtained. Women were considered to have IMN adenopathy when nodes seen on MRI or having standardized uptake value (SUV) greater than mediastinal blood pool decreased in either size or SUV (or both) after treatment. Features including lymphovascular invasion, tumor quadrant(s), and axillary adenopathy were compared between presence and absence of IMN adenopathy using Fisher's exact test. Prevalence was determined on the basis of the percentage of patients with IMN adenopathy by either modality. The McNemar test compared the prevalence of IMN adenopathy on MRI to its prevalence on PET/CT.

RESULTS

Prevalence of IMN adenopathy was 16% (14/90) by MRI and 14% (13/90) by PET/CT (p = 0.317). After chemotherapy, IMN adenopathy resolved in 12 of 14 patients (86%). In two patients with poor responses in primary tumors, IMN adenopathy persisted, and both patients developed metastatic disease within 6 months. At 3 years, survival was significantly worse in patients with IMN adenopathy than in those without (85.7% vs 53.3%, respectively; p = 0.009).

CONCLUSION

In women with advanced breast cancer receiving neoadjuvant chemo-therapy, prevalence of IMN adenopathy was 16%, equally detected by breast MRI and PET/CT. Identification of IMN adenopathy may affect treatment and provides prognostic information.

Incidence and Potential Significance of Internal Mammary Lymphadenopathy on Computed Tomography in Patients with a Diagnosis of Primary Breast Cancer

INTRODUCTION

The importance of internal mammary nodes (IMNs) in the staging and treatment of breast cancer patients is controversial.

METHODS

A retrospective cohort of patients diagnosed with primary breast cancer over a 4-year period (January 2009 to December 2012) was assessed. The number and size of any IMNs visible on spiral computed tomography (CT) were recorded.

RESULTS

A total of 830 patients were diagnosed with primary breast cancer within the identified time frame, of which 150 patients met the inclusion criteria. Of these 42% (63) had IMNs present, although the majority were small (<5 mm). However, 16% (25) had larger nodes, greater than 5 mm in short axis, present on CT. Significantly more patients with the presence of large (>5 mm) IMNs had more advanced disease with CT evidence of other distant spread.

CONCLUSION

We have demonstrated that IMNs are present in a substantial number of our primary breast cancer patients. We suggest that further histological research is required to establish reliable CT size criterion for pathological IMNs. In addition, routine imaging of the IM chain, as well as axilla, should be considered in the staging of breast cancer.

Breast cancer patient with an uncommon lymphatic drainage evidenced by SPECT/CT

SPECT/CT reinforces the role of lymphoscintigraphy in breast cancer by solving some cases with difficult reading on planar scintigraphy. An 80-year-old woman was referred to our institution for management of a screen-detected, nonpalpable, invasive lobular carcinoma of lower inner quadrant of the left breast. Lymphoscintigraphy was performed before surgery. Planar images showed an axillary sentinel node and 2 medially located hot spots. SPECT/CT allowed determining that one of the extra-axillary drainage sites was to the internal mammary basin, while the second corresponded to a mediastinal lymph node. Although this drainage was unexpected, mediastinum is a common site of breast cancer recurrence.

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.

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.

Adjuvant radiotherapy of regional lymph nodes in breast cancer - a meta-analysis of randomized trials

Background

Radiotherapy (RT) improves overall survival (OS) of breast cancer patients after breast conserving surgery and after mastectomy in patients with involved lymph nodes (LN). The contribution of RT to the regional LN to this survival benefit was poorly understood. Recently, the results of three large randomized trials addressing this question have become available.

Material and methods

The published abstracts (full publication pending) of the MA.20 (n=1832) and the EORTC 22922–10925 (EORTC) (n=4004) trial and the full publication of the French trial (n=1334) were basis of the meta-analysis. Main eligibility criteria were positive axillary LN (all trials), LN negative disease with high risk for recurrence (MA.20), and medial/central tumor location (French, EORTC). The MA.20 and the EORTC trial tested the effect of additional regional RT to the internal mammary (IM) LN and medial supraclavicular (MS) LN, whereas in the French trial all patients received RT to the MS-LN and solely RT to the IM-LN was randomized. Primary endpoint was OS. Secondary endpoints were disease-free survival (DFS) and distant metastasis free survival (DMFS).

Results

Regional RT of the MS-LN and the IM-LN (MA.20 and EORTC) resulted in a significant improvement of OS (Hazard Ratio (HR) 0.85 (95% CL 0.75 - 0.96)). Adding the results of the French trial and using the random effects model to respect the different design of the French trial, the effect on OS of regional radiotherapy was still significant (HR 0.88 (95% CL 0.80 - 0.97)). The absolute benefits in OS were 1.6% in the MA.20 trial at 5 years, 1.6% in the EORTC trial at 10 years, and 3.3% in the French trial at 10 years (not significant in single trials). Regional radiotherapy of the MS-LN and the IM-LN (MA.20 and EORTC) was associated with a significant improvement of DFS (HR 0.85 (95% CL 0.77 - 0.94)) and DMFS (HR 0.82 (95% CL 0.73 - 0.92)). The effect sizes were not significantly different between trials for any end point.

Conclusion

Additional regional radiotherapy to the internal mammary and medial supraclavicular lymph nodes statistically significantly improves DFS, DMFS, and overall survival in stage I-III breast cancer.

Detection of internal mammary lymph node metastasis with (18)F-fluorodeoxyglucose positron emission tomography/computed tomography in patients with stage III breast cancer

PURPOSE

The present study assessed the positive predictive value (PPV) of (18)F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) for the detection of internal mammary node (IMN) metastasis in patients with clinical stage III breast cancer.

METHODS

Patients who were diagnosed with clinical stage III breast cancer and underwent pretreatment (18)F-FDG PET/CT were retrospectively analyzed. The (18)F-FDG PET/CT scans were prospectively reviewed by two board-certified nuclear medicine physicians in a blinded manner. The intensities of IMNs were graded into four categories (no activity and lower, similar, and higher activities than that of the mediastinal blood pool). IMNs were measured from the combined CT (largest diameter of the short axis). Histologic data of the IMNs were obtained by ultrasonography-guided fine-needle aspiration biopsy or surgical excision. The PPV was calculated for pathologically confirmed IMNs. Visual grade, maximum standardized uptake values (SUVmax), and sizes were analyzed according to the pathology results.

RESULTS

There were 249 clinical stage III breast cancer patients (age 48.0 ± 10.1 years, range 26-79 years) who had undergone initial (18)F-FDG PET/CT prior to treatment. Excluding 33 cases of stage IV breast cancer, 62 of 216 patients had visible IMNs on (18)F-FDG PET/CT, and histologic confirmation was obtained in 31 patients. There were 27 metastatic and four nonmetastatic nodes (PPV 87.1%). Metastatic nodes mostly presented with visual grade 3 (83.9%), and SUVmax and size were 3.5 ± 4.3 and 5.6 ± 2.0 mm, respectively.

CONCLUSION

(18)F-FDG PET/CT has a high PPV for IMN metastasis in clinical stage III breast cancer, indicating the possibility of metastasis in IMNs with FDG uptake similar to/lower than that of the blood pool or small-sized nodes.

The Metastatic Rate of Internal Mammary Lymph Nodes When Metastasis of Internal Mammary Lymph Node Is Suspected on PET/CT

Purpose

Metastatic status of internal mammary lymph node (IMLN) has a clinical importance in assessing the stage and prognosis of breast cancer. But, when metastasis of IMLN is suspected; the management is controversial. We retrospectively reviewed 36 breast cancer patients who underwent IMLN biopsy, and investigated the pathologic status of IMLN which suspected metastasis with positron emission tomography and computed tomography (PET/CT).

Methods

From January 2007 to December 2012, 36 patients underwent IMLN biopsy for suspected IMLN metastasis on PET/CT, when diagnosed with primary or recurrent breast cancer. Clinicopathologic features of these patients and metastatic status of IMLNs were investigated.

Results

A total of 36 patients were included in this study. Twenty-four patients diagnosed with primary breast cancer and 12 patients diagnosed with recurrent breast cancer underwent IMLN biopsy. The mean number of IMLNs was 2.72±2.05, and the total metastatic rate of IMLNs was 72.2% (26 out of 36). IMLN metastasis was confirmed on pathologic examination in 19 patients (79.2%, 19 out of 24) with primary breast cancer and in 7 patients (58.3%, 7 out of 12) with recurrent breast cancer. The mean standardized uptake values of metastatic and nonmetastatic IMLNs in primary breast cancer were 3.50±2.51 and 3.72±3.55, respectively and those of metastatic and nonmetastatic IMLN in recurrent breast cancer were 3.92±2.67 and 4.12±3.57, respectively. In both groups, there was no statistically significant difference between the SUVs of metastatic and nonmetastatic IMLNs (p=0.291 and p=0.951, respectively).

Conclusion

Due to the recent advances in diagnostic and surgical skills, IMLN biopsy can be performed safely without any complications without performing radical mastectomy. If IMLN metastasis is suspected on PET/CT, IMLN biopsy is useful to assess the exact stage and to determine the treatment for breast cancer. Further follow-up studies are needed to assess the locoregional recurrence and to compare the improvement in overall survival and disease-free survival.

(18)F-FDG PET/CT-positive internal mammary lymph nodes: pathologic correlation by ultrasound-guided fine-needle aspiration and assessment of associated risk factors

OBJECTIVE

Metastatic breast cancer in internal mammary (IM) lymph nodes is associated with a poor prognosis. This study correlates (18)F-FDG PET/CT-positive IM lymph nodes with ultrasound-guided fine-needle aspiration (FNA) cytopathologic results and determines risk factors for IM node positivity on PET/CT.

MATERIALS AND METHODS

For this retrospective study, a database search was performed to identify patients referred for whole-body (18)F-FDG PET/CT for initial staging or restaging of breast cancer from January 1, 2005, through December 31, 2010. The radiology reports and images were reviewed for patients with (18)F-FDG-avid IM lymph nodes on PET/ CT and correlated with the cytopathologic results from FNA of selected PET/CT-positive IM lymph nodes. The patients with positive IM nodes on PET/CT who underwent PET/CT for initial staging were compared against age-matched and tumor size-matched patients to identify risk factors for IM node positivity on PET/CT.

RESULTS

One hundred ten of 1259 patients (9%) had an (18)F-FDG-avid IM lymph node on PET/CT. Twenty-five patients underwent ultrasound-guided FNA of a suspicious IM node, and 20 IM lymph nodes (80%) were cytologically proven metastases from the primary breast malignancy. High tumor grade, the presence of lymphovascular invasion (LVI), and triple receptor-negative hormonal receptor status were found to be significant risk factors for IM node positivity on PET/CT (p < 0.05).

CONCLUSION

Although fewer than 10% of breast cancer patients have positive IM nodes on (18)F-FDG PET/CT performed for initial staging or restaging, a positive IM node indicates a very high likelihood of malignant involvement on ultrasound-guided FNA. The presences of high tumor grade, LVI, or triple receptor-negative status are risk factors for IM node positivity on (18)F-FDG PET/CT.

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.

False Positive 18F-FDG Uptake in Mediastinal Lymph Nodes Detected with Positron Emission Tomography in Breast Cancer: A Case Report

Breast cancer is the most frequently diagnosed cancer among females. It is accepted that lymph node involvement with metastatic tumor and the presence of distant metastasis are the most important prognostic factors. Accurate staging is important in determining prognosis and appropriate treatment. Positron emission tomography with computed tomography detects malignancies using 2-[18F]-fluoro-2-deoxy-d-glucose (18F-FDG PET CT) with high accuracy and they contribute to decisions regarding diagnosis, staging, recurrence, and treatment response. Here, we report a case of false positive metastatic mediastinal lymph nodes that were diagnosed by 18F-FDG PET CT in a 40-year-old breast cancer patient who had undergone preoperative evaluation. Right paratracheal, prevascular, aorticopulmonary, precarinal, subcarinal, hilar, and subhilar multiple conglomerated mediastinal lymph nodes were revealed in addition to left breast mass and axillary lymph nodes. Mediastinoscopy was performed with biopsy and pathology was reported as granulomatous lymphadenitis. In conclusion, any abnormal FDG accumulation in unusual lymph nodes must be evaluated carefully and confirmed histopathologically.

The Effects of Preoperative (18)F-FDG PET/CT in Breast Cancer Patients in Comparison to the Conventional Imaging Study

PURPOSE

There have been recent studies of the (18)F-fluorodeoxyglucose positron emission tomography and computed tomography ((18)F-FDG PET/CT) in the staging, detection, and follow-up of the breast cancer occurrence and recurrence. There was controversy concerning the use of (18)F-FDG PET/CT for staging primary breast cancer. In this study, we investigated the potential effects of (18)F-FDG PET/CT in the initial assessment of patients with primary breast cancer.

METHODS

From January 2008 to December 2009, 154 consecutive biopsy-proven invasive breast cancer patients were enrolled in this study. Patients underwent conventional imaging studies including mammography, breast ultrasonography (USG), and magnetic resonance imaging for local assessment, and plain chest X-ray, liver USG, and bone scan to rule out distant metastasis. All 154 patients underwent (18)F-FDG PET/CT in the initial assessment.

RESULTS

(18)F-FDG PET/CT did not detect primary breast lesions in 16 patients with a sensitivity of 89.6% and detected only 5 multiple lesions (12.5%) out of 40 cases. Histologically confirmed axillary lymph node (LN) metastases were in 51 patients, and the sensitivity and specificity of (18)F-FDG PET/CT to detect metastatic axilla were 37.3% and 95.8%, respectively; whereas the corresponding estimates of USG were 41.2% and 93.7%, respectively. Eleven extra-axillary LN metastases were found in eight patients, and seven lesions were detected by (18)F-FDG PET/CT only. The sensitivity and specificity of (18)F-FDG PET/CT in detecting distant metastasis were 100% and 96.4%, respectively; whereas the sensitivity and specificity of the conventional imaging were 61.5% and 99.2%, respectively.

CONCLUSION

(18)F-FDG PET/CT cannot be recommended as a primary diagnostic procedure in breast cancer, but it has the potential to be used as an additional imaging tool for the detection of axillary metastasis, distant metastasis, and extra-axillary LN metastasis. (18)F-FDG PET/CT cannot solely replace the conventional diagnostic procedure in primary breast cancer. The best approach may be the combination of different imaging modalities.

Synthesis and evaluation of novel gonadotropin-releasing hormone receptor-targeting peptides

The purpose of this study was to develop novel radiolabeled gonadotropin-releasing hormone (GnRH) receptor-targeting peptides for breast cancer imaging. Three novel 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA)-conjugated GnRH peptides were designed and synthesized. The radiometal chelator DOTA was conjugated to the epsilon or alpha amino group of D-lysine, or the epsilon amino group of L-lysine via an Ahx {aminohexanoic acid} linker to generate DOTA-Ahx-(D-Lys(6)-GnRH1), DOTA-Ahx-(D-Lys(6)-GnRH2) and DOTA-Ahx-(L-Lys(6)-GnRH3), respectively. The conjugation of the DOTA to the epsilon amino group of D-lysine (rather than alpha amino group of D-lysine nor epsilon amino group of L-lysine) maintained the nanomolar GnRH receptor binding affinity. The IC(50) values of DOTA-Ahx-(D-Lys(6)-GnRH1), DOTA-Ahx-(D-Lys(6)-GnRH2) and DOTA-Ahx-(L-Lys(6)-GnRH3) were 36.1 nM, 10.6 mM and 4.3 mM, respectively. Since only DOTA-Ahx-(D-Lys(6)-GnRH1) displayed nanomolar receptor binding affinity, the specific GnRH receptor binding of (111)In-DOTA-Ahx-(D-Lys(6)-GnRH1) was determined in human GnRH receptor membrane preparations. Furthermore, the biodistribution and tumor imaging properties of (111)In-DOTA-Ahx-(D-Lys(6)-GnRH1) were examined in MDA-MB-231 human breast cancer-xenografted nude mice. (111)In-DOTA-Ahx-(D-Lys(6)-GnRH1) exhibited specific GnRH receptor binding and rapid tumor uptake (1.76 ± 0.58% ID/g at 0.5 h postinjection) coupled with fast whole-body clearance through the urinary system. The MDA-MB-231 human breast cancer-xenografted tumor lesions were clearly visualized by single photon emission computed tomography (SPECT)/CT at 1 h postinjection of (111)In-DOTA-Ahx-(D-Lys(6)-GnRH1). The profound impact of DOTA position on the binding affinity of the GnRH peptide provided a new insight into the design of novel radiolabeled GnRH peptides. The successful imaging of MDA-MB-231 human breast cancer-xenografted tumor lesions using (111)In-DOTA-Ahx-(D-Lys(6)-GnRH1) suggested its potential as a novel imaging probe for human breast cancer imaging.

Could the serial determination of Ca15.3 serum improve the diagnostic accuracy of PET/CT?: results from small population with previous breast cancer

OBJECTIVES

A single value of tumor marker elevation is not used for the diagnosis of breast cancer (BC) relapse, whereas the serial measurements which confirm a persistent Ca15.3 increase can represent an early signal of tumor relapse, even if described in asymptomatic patients without any other clinical or instrumental signs of cancer. The aim of this study was to assess the relationship between serial measures of Ca15.3 and 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) findings in patients with already treated BC during follow-up.

METHODS

We retrospectively selected 60 patients (mean age 62 ± 11 years) with previous history of BC, already treated with surgery and other treatments. Three serial measures of Ca15.3 were collected within 1 year before PET/CT examination, respectively, at 12-9 months (297 ± 30 days), 9-3 months (154 ± 51 days) and 3-0 months (46 ± 28 days). Clinical outcome or imaging follow-up data were used to define disease relapse. The increase in tumor marker value was compared with PET/CT results and disease relapse. Coefficient of variation (CV) and ROC curves were used. Disease-free survival (DFS) curves were computed by Kaplan-Meier method.

RESULTS

PET/CT was negative in 36 (60%) and positive in 24 (40%) patients. The median time between initial treatment and PET/CT was 3 years. CV of the Ca15.3 serial determinations was significantly higher in patients with positive than negative PET/CT (39 vs. 24%, p < 0.05). Disease relapse was found in 25 (42%) patients, of these 21 (88%) had positive PET/CT. ROC analyses showed that an increase of Ca15.3 between the 2nd and 3rd measures have better individuated positive PET/CT and disease relapse (AUC 0.65 and 0.64, respectively; p < 0.05). DFS was higher in patients with negative than positive PET/CT (65 vs. 15%, p < 0.05).

CONCLUSIONS

Serial increase of Ca15.3 could be considered optimal to address FDG PET/CT examination during BC patients follow-up. PET/CT performed just on time might allow, earlier and with higher diagnostic accuracy, the detection of disease relapse in BC patients.

Breast cancer

Diagnostic imaging modalities utilized in the care of cancer patients must fulfill several requirements: they must diagnose and characterize tumors with high accuracy, must reliably stage and restage the disease, and should allow for monitoring the effects of therapeutic interventions on the course of the disease. They should impact management by guiding treating physicians to appropriate individualized treatment strategies. There is ample evidence that positron emission tomography (PET) and PET-computed tomography (CT) imaging can meet these requirements. This chapter discusses the role and contributions of PET and PET-CT imaging using (18)F-fluorodeoxyglucose in diagnosing, staging, restaging, and treatment monitoring of breast cancer. Novel molecular imaging probes and devices that have been developed and translated into early clinical research protocols are also introduced.