Evaluation of liver metastases after radiofrequency ablation: utility of 18F-FDG PET and PET/CT

OBJECTIVE: Our objective was to review the CT appearance of liver metastases after radiofrequency ablation and to describe the imaging findings of and utility of (18)F-FDG PET and PET/CT in assessing tumor recurrence after ablation. CONCLUSION: (18)F-FDG PET and PET/CT can provide added diagnostic information compared with conventional imaging in patients after radiofrequency ablation of liver metastases and can be useful in guiding repeat ablation procedures.     

18F-FDG PET/CT in evaluation of radiofrequency ablation of liver metastasis

Image-guided radiofrequency ablation (RFA) is a minimally invasive therapy option in the treatment of primary and secondary hepatic malignancies, which are not suitable for surgery/chemotherapy, and more recently, for tumors with limited hepatic involvement and solitary liver metastasis. Accurate assessment of treatment response after RFA remains a concern. Conventional imaging modalities have limitations of differentiation between residual/recurrence from post-RFA changes. We illustrate images of 3 patients in whom (18)F-FDG PET/CT was used for response assessment and restaging after RFA in liver tumors.     

The usefulness of 18F-FDG PET/MRI fusion image in diagnosing pancreatic tumor: comparison with 18F-FDG PET/CT

Purpose

This study aimed at demonstrating the feasibility of retrospectively fused ¹⁸F FDG-PET and MRI (PET/MRI fusion image) in diagnosing pancreatic tumor, in particular differentiating malignant tumor from benign lesions. In addition, we evaluated additional findings characterizing pancreatic lesions by FDG-PET/MRI fusion image.

Methods

We analyzed retrospectively 119 patients: 96 cancers and 23 benign lesions. FDG-PET/MRI fusion images (PET/T1 WI or PET/T2WI) were made by dedicated software using 1.5 Tesla (T) MRI image and FDG-PET images. These images were interpreted by two well-trained radiologists without knowledge of clinical information and compared with FDG-PET/CT images. We compared the differential diagnostic capability between PET/CT and FDG-PET/MRI fusion image. In addition, we evaluated additional findings such as tumor structure and tumor invasion.

Results

FDG-PET/MRI fusion image significantly improved accuracy compared with that of PET/CT (96.6 vs. 86.6 %). As additional finding, dilatation of main pancreatic duct was noted in 65.9 % of solid types and in 22.6 % of cystic types, on PET/MRI-T2 fusion image. Similarly, encasement of adjacent vessels was noted in 43.1 % of solid types and in 6.5 % of cystic types. Particularly in cystic types, intra-tumor structures such as mural nodule (35.4 %) or intra-cystic septum (74.2 %) were detected additionally. Besides, PET/MRI-T2 fusion image could detect extra benign cystic lesions (9.1 % in solid type and 9.7 % in cystic type) that were not noted by PET/CT.

Conclusions

In diagnosing pancreatic lesions, FDG-PET/MRI fusion image was useful in differentiating pancreatic cancer from benign lesions. Furthermore, it was helpful in evaluating relationship between lesions and surrounding tissues as well as in detecting extra benign cysts.     

Initial clinical results of simultaneous 18F-FDG PET/MRI in comparison to 18F-FDG PET/CT in patients with head and neck cancer

Purpose

The aim of this study was to evaluate the diagnostic capability of simultaneous ¹⁸F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/MRI compared to ¹⁸F-FDG PET/CT as well as their single components in head and neck cancer patients.

Methods

In a prospective study 17 patients underwent ¹⁸F-FDG PET/CT for staging or follow-up and an additional ¹⁸F-FDG PET/MRI scan with whole-body imaging and dedicated examination of the neck. MRI, CT and PET images as well as PET/MRI and PET/CT examinations were evaluated independently and in a blinded fashion by two reader groups. Results were compared with the reference standard (final diagnosis determined in consensus using all available data including histology and follow-up). Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were calculated.

Results

A total of 23 malignant tumours were found with the reference standard. PET/CT showed a sensitivity of 82.7 %, a specificity of 87.3 %, a PPV of 73.2 % and a NPV of 92.4 %. Corresponding values for PET/MRI were 80.5, 88.2, 75.6 and 92.5 %. No statistically significant difference in diagnostic capability could be found between PET/CT and PET/MRI. Evaluation of the PET part from PET/CT revealed highest sensitivity of 95.7 %, and MRI showed best specificity of 96.4 %. There was a high inter-rater agreement in all modalities (Cohen’s kappa 0.61–0.82).

Conclusion

PET/MRI of patients with head and neck cancer yielded good diagnostic capability, similar to PET/CT. Further studies on larger cohorts to prove these first results seem justified.     

Evaluation of lymph node status after neoadjuvant chemotherapy in breast cancer patients: comparison of diagnostic performance of ultrasound,MRI and 18F-FDG PET/CT

Objective:

To evaluate the diagnostic performance of ultrasound, MRI and fluorine-18 fludeoxyglucose positron emission tomography (¹⁸F-FDG PET)/CT for the diagnosis of metastatic axillary lymph node (ALN) after neoadjuvant chemotherapy (NAC) and to find out histopathological factors affecting the diagnostic performance of these imaging modalities.

Methods:

From January 2012 to November 2014, 191 consecutive patients with breast cancer who underwent NAC before surgery were retrospectively reviewed. We included 139 patients with ALN metastasis that was confirmed on fine needle aspiration or core needle biopsy at initial diagnosis.

Results:

After NAC, 39 (28%) patients showed negative conversion of ALN on surgical specimens of sentinel lymph node (LN) or ALN. The sensitivity of ultrasound, MRI and PET/CT was 50% (48/96), 72% (70/97) and 22% (16/73), respectively. The specificity of ultrasound, MRI and PET/CT was 77% (30/39), 54% (21/39) and 85% (22/26), respectively. The Az value of combination of ultrasound and PET/CT was the highest (0.634) followed by ultrasound (0.626) and combination of ultrasound, MRI and PET/CT (0.617). The size of tumour deposit in LN and oestrogen receptor was significantly associated with the diagnostic performance of ultrasound (p < 0.001 and p = 0.009, respectively) and MRI (p = 0.045 and p = 0.036, respectively). The percentage diameter decrease, size of tumour deposit in LN, progesterone receptor, HER2 and histological grade were significantly associated with the diagnostic performance of PET/CT (p = 0.023, p = 0.002, p = 0.036, p = 0.044 and p = 0.008, respectively). On multivariate logistic regression analysis, size of tumour deposit within LN was identified as being independently associated with diagnostic performance of ultrasound [odds ratio, 13.07; 95% confidence interval (CI), 2.95–57.96] and PET/CT (odds ratio, 6.47; 95% CI, 1.407–29.737).

Conclusion:

Combination of three imaging modalities showed the highest sensitivity, and PET/CT showed the highest specificity for the evaluation of ALN metastasis after NAC. Ultrasound alone or combination of ultrasound and PET/CT showed the highest positive-predictive value. The size of tumour deposit within ALN was significantly associated with diagnostic performance of ultrasound and PET/CT.

Advances in knowledge:

This study is about the diagnostic performance of ultrasound, MRI, PET/CT and combination of each imaging modality for the evaluation of metastatic ALN after NAC. Of many histopathological factors, only the size of tumour deposit within ALN was an independent factor associated with the diagnostic performance of ultrasound and PET/CT.Axillary lymph node (ALN) metastasis is one of the most significant prognostic factors in patients with breast cancer. As the management of axillary lesions has been diverse, the detection of axillary nodal lesion has been more important. The diagnostic accuracy of ultrasound and MRI for the detection of metastatic ALNs has been studied by many researchers. Sensitivity and specificity of ultrasound for the detection of metastatic ALNs have been reported as 41.2–70.8% and 54.5–93.7%.^1–4 Sensitivity and specificity of MRI have been reported as 36–79% and 93–100%, respectively.^4–6Neoadjuvant chemotherapy (NAC) has become the standard treatment not only in patients with locally advanced breast cancer but also in early invasive breast cancer in an attempt to downstage the primary cancer and to reduce micrometastasis. If the ALN metastasis is confirmed on fine needle aspiration biopsy (FNAB) or core needle biopsy (CNB) at initial diagnosis, ALN dissection (ALND) is usually performed, regardless of the responsiveness of ALN. Residual metastatic lesion of ALNs after NAC is an important prognostic factor of disease-free survival.^7,8In ACOSOG Z1071 trial, in patients with breast cancer with clinical N1 stage receiving NAC, if two or more sentinel lymph nodes (SLNs) were removed, the false-negative rate of SLN biopsy (SLNB) was relatively low, 12.6%. Therefore, the role of axillary imaging in NAC setting should be to find out metastatic lymph nodes (LNs) for surgeons to proceed directly to ALND. Another role could be to correctly diagnose negative LN to safely omit SLNB. Despite the importance of restaging of nodal status, there have been few studies about diagnostic accuracy of imaging modalities for detection of metastatic ALNs after NAC.The purpose of our study was to evaluate the diagnostic performance of ultrasound, MRI and fluorine-18 fludeoxyglucose positron emission tomography (¹⁸F-FDG PET)/CT for the diagnosis of metastatic ALNs after NAC and to find out histopathological factors affecting the diagnostic accuracy of these imaging modalities.     

18F-FDG PET/CT结合MRI在癫（癎）外科治疗中的应用

目的 探讨18F-脱氧葡萄糖（FDG）PET/CT结合MRI定位致（癎）灶,指导癫（癎）外科治疗的意义.方法 67例癫（癎）外科治疗患者术前均行18F-FDG PET/CT和MRI检查,根据术前评估以及术中皮质脑电图监测结果进行致（癎）灶切除术.术后长期随访,根据Engel分级将患者分为癫（癎）发作完全控制组（Engel Ⅰ）和癫（癎）发作未完全控制组（Engel Ⅱ～Ⅳ）,采用x2检验或Fisher精确检验对数据进行分析.结果 67例中48例患者术后癫（癎）发作完全控制（Engel Ⅰ,71.6%）,11例Engel Ⅱ,5例Engel Ⅲ,3例Engel Ⅳ.18F-FDG PET/CT定位定侧结果与MRI检查结果一致或基本一致者63例,其中71.4%（45/63）术后癫（癎）发作完全控制;18F-FDG PET/CT与MRI检查结果不一致者4例,其中3例术后癫（癎）发作完全控制,2组差异无统计学意义（Fisher精确检验,P＞0.05）.63例中MRI与18F-FDG PET/CT均发现局限性异常者为41例,其中80.5%（33/41）术后癫（癎）发作完全控制;MRI发现局限性病变,但18F-FDG PET/CT呈更广泛性代谢异常者20例,其中55.0%（11/20）术后癫（癎）发作完全控制,2组差异有统计学意义（x2=4.34,P＜0.05）.结论 18F-FDG PET/CT结合MRI可为致（癎）灶定位及预后评估提供重要信息.     

Fusion of PET and MRI for staging of uterine cervical cancer: comparison with contrast-enhanced 18F-FDG PET/CT and pelvic MRI

PurposeTo investigate the fusion of pelvic magnetic resonance imaging (MRI) and fluorodeoxyglucose positron emission tomography (PET) for assessment of locoregional extension and nodal staging of cervical cancer.MethodsPET/computed tomography (CT), MRI, and non-fused and fusion of PET and MRI for assessing the extent of the primary tumor and metastasis to nodes were evaluated.ResultsAccuracy for T-status was 83.3% for fused and non-fused PET/MRI and MRI proved significantly more accurate than PET/CT (53.3%) (P= .0077). Sensitivity, specificity, and accuracy for nodal metastasis were 92.3%, 88.2%, and 90.0% for fused PET/MRI and PET/contrast-enhanced CT; 84.6%, 94.1%, and 90.0% for non-fused PET/MRI; and 69.2%, 100%, and 86.7% for MRI.ConclusionFused PET/MRI combines the individual advantages of MRI and PET.     

Detection of neck recurrence in patients with differentiated thyroid cancer: comparison of ultrasound, contrast-enhanced CT and 18F-FDG PET/CT using surgical pathology as a reference standard: (ultrasound vs. CT vs. 18F-FDG PET/CT in recurrent thyroid cancer)

Objectives

To compare the diagnostic performance of ultrasound, contrast-enhanced computed tomography (CT) and ¹⁸F-FDG positron emission tomography (PET)/CT for detecting recurrent differentiated thyroid cancer in the neck.

Methods

Twenty patients who had undergone previous surgery for differentiated thyroid cancer (19 papillary carcinomas; 1 medullary carcinoma) and presented with pathologically proven recurrence in the neck were included. All patients had undergone ultrasound, CT and PET/CT in the 2 months before further surgery. In each patient, ultrasound, CT and PET/CT images were retrospectively reviewed to determine the presence of loco-regional recurrence by level-by-level analysis. Imaging results were correlated with the histological evaluation of the neck dissection as a standard of reference.

Results

Recurrences were found at 52 out of 110 cervical nodal levels surgically explored. The sensitivity, specificity and accuracy were 69.2 %, 89.7 % and 80.0 % for ultrasound; 63.5 %, 94.8 % and 80.0 % for CT; and 53.8 %, 79.3 % and 67.3 % for PET/CT, respectively. ROC analysis revealed higher diagnostic performance with ultrasound than with PET/CT for detecting recurrent tumour.

Conclusions

Although no significant difference was found among the three techniques, the sensitivity and specificity of ultrasound and CT were higher than those of PET/CT for the evaluation of cervical recurrence in patients with differentiated thyroid cancer.

Key Points

? Ultrasound, CT and ¹⁸ F-FDG PET/CT can all detect recurrent thyroid cancer. ? Ultrasound and CT have higher sensitivity and specificity. ? Ultrasound, CT and ¹⁸ F-FDG PET/CT frequently demonstrated discordant findings     

18F-FDOPA PET/CT for detection of recurrence in patients with glioma: prospective comparison with 18F-FDG PET/CT

Purpose

Differentiation between recurrence and radiation necrosis in patients with glioma is crucial, since the two entities have completely different management and prognosis. The purpose of the present study was to compare the efficacies of ¹⁸F-FDG PET/CT and 3,4-dihydroxy-6-[¹⁸F]fluoro-phenylalanine (¹⁸F-FDOPA) PET/CT in detection of recurrent gliomas.

Methods

A total of 28 patients (age 38.82?±?1.25 years; 85.7 % men) with histopathologically proven glioma with clinical/imaging suspicion of recurrence were evaluated using ¹⁸F-FDG PET/CT and ¹⁸F-FDOPA PET/CT. ¹⁸F-FDG PET/CT and ¹⁸F-FDOPA PET/CT images were evaluated qualitatively and semiquantitatively. The combination of clinical follow-up, repeat imaging and/or biopsy (when available) was taken as the reference standard.

Results

Based on the reference standard, 21 patients were positive and 7 were negative for tumour recurrence. The sensitivity, specificity and accuracy of ¹⁸F-FDG PET/CT were 47.6 %, 100 % and 60.7 %, respectively, and those of ¹⁸F-FDOPA PET/CT were 100 %, 85.7 % and 96.4 %, respectively. The results of ¹⁸F-FDG PET/CT and ¹⁸F-FDOPA PET/CT were concordant in 57.1 % of patients (16 of 28) and discordant in 42.9 % (12 of 28). The difference in the findings between ¹⁸F-FDG PET/CT and ¹⁸F-FDOPA PET/CT was significant (P?=?0.0005, McNemar’s test). The difference was significant for low-grade tumours (P?=?0.0039) but not for high-grade tumours (P?=?0.250).

Conclusion

¹⁸F-FDOPA PET/CT is highly sensitive and specific for detection of recurrence in glioma patients. It is superior to ¹⁸F-FDG PET/CT for this purpose and is especially advantageous in patients with low-grade gliomas.     

18F-FDG PET/CT changes therapy management in high-risk DTC after first radioiodine therapy

Purpose

Advanced tumour stage and initial metastases are associated with reduced general and tumour-free survival in patients with differentiated thyroid carcinoma. Optimal initial therapy is mandatory for a positive patient outcome, but can only be performed if all non-iodine-avid tumour lesions are known before planning treatment. We analysed the benefit of ¹⁸F-FDG PET/CT at initial diagnosis in patients with high-risk differentiated thyroid carcinoma and determined whether the ¹⁸F-FDG PET/CT results led to a deviation from the standard procedure, which consists of two consecutive radioiodine treatments with thyroid hormone suppression in between and no additional imaging, with individual patient management.

Methods

The study group comprised 90 consecutive patients with either extensive or metastasized high-risk differentiated thyroid carcinoma who received ¹⁸F-FDG PET/CT after the first radioiodine treatment approximately 4?weeks after thyroidectomy under endogenous TSH stimulation. We carried out PET/CT imaging with low-dose CT without contrast medium, which we only used for attenuation correction of PET images.

Results

¹⁸F-FDG PET/CT was positive in 26 patients (29%) and negative in 64 patients (71%). Compared to the results of posttherapeutic ¹³¹I whole-body scintigraphy, the same lesions were PET-positive in 7 of the 26 patients, different lesions were PET-positive in 15 patients, and some PET-positive lesions were the same and some were different in 4 patients. TNM staging was changed due to the PET results in 8 patients. Management was changed in 19 of the 90 patients (21%), including all patients with only FDG-positive lesions and all patients with both FDG-positive and iodine-positive lesions. Age was not a predictive factor for the presence of FDG-positive lesions. FDG-positive and iodine-positive lesions were associated with high serum thyroglobulin. However, at low serum thyroglobulin values, tumour lesions (iodine- and/or FDG-avid) were also diagnosed. Thus, the serum thyroglobulin value prior to the first radioiodine treatment cannot be used as a predictor of the presence of FDG-positive lesions.

Conclusion

¹⁸F-FDG PET/CT resulted in a change of therapeutic procedure in 11 of 90 patients and in a change of patient management through additional diagnostic measures in 8 of 90 patients, and is consequently very helpful in initial staging. At our hospital, ¹⁸F-FDG PET/CT in high-risk patients with differentiated thyroid carcinoma has been established as an initial staging modality.     

^18F-FDG PET／CT在诊断转移性肝肿瘤中的应用

目的：探讨^18F-FDG PEF／CT在诊断转移性肝肿瘤中的应用。方法：回顾性分析49例转移性肝肿瘤患者的PET／CT影像资料,探讨^18F-FDG PET／CT诊断转移性肝肿瘤的影像表现及应用价值。结果：49例转移性肝肿瘤患者中45例^18F-FDG PET／CT表现为病灶^18F-FDG摄取明显高于周围正常肝组织;其中25例进行了延迟显像,22例表现为SUVmax及T／N值明显升高;发现肝转移同时伴有肝外转移患者38例。结论：^18F-FDG PET／CT诊断转移性肝肿瘤灵敏度高,准确,并可以同时对全身情况加以评价,对肿瘤患者肝转移的评价及治疗具有重要指导作用。     

18F-FDG PET and PET/CT in fever of unknown origin.

Fever of unknown origin (FUO) was originally defined as recurrent fever of 38.3 degrees C or higher, lasting 2-3 wk or longer, and undiagnosed after 1 wk of hospital evaluation. The last criterion has undergone modification and is now generally interpreted as no diagnosis after appropriate inpatient or outpatient evaluation. The 3 major categories that account for most FUOs are infections, malignancies, and noninfectious inflammatory diseases. The diagnostic approach in FUO includes repeated physical investigations and thorough history-taking combined with standardized laboratory tests and simple imaging procedures. Nevertheless, there is a need for more complex or invasive techniques if this strategy fails. This review describes the impact of (18)F-FDG PET in the diagnostic work-up of FUO. (18)F-FDG accumulates in malignant tissues but also at the sites of infection and inflammation and in autoimmune and granulomatous diseases by the overexpression of distinct facultative glucose transporter (GLUT) isotypes (mainly GLUT-1 and GLUT-3) and by an overproduction of glycolytic enzymes in cancer cells and inflammatory cells. The limited data of prospective studies indicate that (18)F-FDG PET has the potential to play a central role as a second-line procedure in the management of patients with FUO. In these studies, the PET scan contributed to the final diagnosis in 25%-69% of the patients. In the category of infectious diseases, a diagnosis of focal abdominal, thoracic, or soft-tissue infection, as well as chronic osteomyelitis, can be made with a high degree of certainty. Negative findings on (18)F-FDG PET essentially rule out orthopedic prosthetic infections. In patients with noninfectious inflammatory diseases, (18)F-FDG PET is of importance in the diagnosis of large-vessel vasculitis and seems to be useful in the visualization of other diseases, such as inflammatory bowel disease, sarcoidosis, and painless subacute thyroiditis. In patients with tumor fever, diseases commonly detected by (18)F-FDG PET include Hodgkin's disease and aggressive non-Hodgkin's lymphoma but also colorectal cancer and sarcoma. (18)F-FDG PET has the potential to replace other imaging techniques in the evaluation of patients with FUO. Compared with labeled white blood cells, (18)F-FDG PET allows diagnosis of a wider spectrum of diseases. Compared with (67)Ga-citrate scanning, (18)F-FDG PET seems to be more sensitive. It is expected that PET/CT technology will further improve the diagnostic impact of (18)F-FDG PET in the context of FUO, as already shown in the oncologic context, mainly by improving the specificity of the method.     

Direct comparison of (18)F-FDG PET and PET/CT in patients with colorectal carcinoma.

The purpose of this study was to compare (18)F-FDG PET and PET/CT in a population of patients with colorectal cancer. METHODS: PET and PET/CT images from 45 patients (17 women, 28 men; mean age +/- SD, 60.8 +/- 11.1 y) with known colorectal cancer referred for PET from June to November 2001 were retrospectively reviewed. Images were acquired with a PET/CT scanner, and (68)Ge attenuation correction was applied. PET images and fused (68)Ge attenuation-corrected PET and CT images were independently and separately interpreted by a moderately experienced reader unaware of the clinical information. Certainty of lesion characterization was scored on a 5-point scale (0 = definitely benign, 1 = probably benign, 2 = equivocal, 3 = probably malignant, 4 = definitely malignant). Lesion location was scored on a 3-point scale (0 = uncertain, 1 = probable, 2 = definite). The presence or absence of tumor was subsequently assessed using all available clinical, pathologic, and follow-up information. Analysis was provided for lesions detected by both PET and PET/CT. RESULTS: The frequency of equivocal and probable lesion characterization was reduced by 50% (50 to 25) with PET/CT, in comparison with PET. The frequency of definite lesion characterization was increased by 30% (84 to 109) with PET/CT. The number of definite locations was increased by 25% (92 to 115) with PET/CT. Overall correct staging increased from 78% to 89% with PET/CT on a patient-by-patient analysis. CONCLUSION: PET/CT imaging increases the accuracy and certainty of locating lesions in colorectal cancer. More definitely normal and definitely abnormal lesions (and fewer probable and equivocal lesions) were identified with PET/CT than with PET alone. Staging and restaging accuracy improved from 78% to 89%.     

18F-FDG PET in characterizing adrenal lesions detected on CT or MRI.

The purpose of this study was to evaluate the ability of (18)F-FDG PET to characterize adrenal lesions in patients with proven or suspected cancers. METHODS: A retrospective analysis was performed on 50 adrenal lesions in 41 patients, whose PET scans were done to evaluate the primary or metastatic disease. CT had shown 50 adrenal lesions in 41 patients and MRI had revealed 13 lesions in 10 patients. There were 34 patients with proven malignancy (28 lung cancer, 3 thyroid cancer, 2 colorectal cancer, and 1 lymphoma) and 7 with lung nodules. Of the 50 lesions, 18 were eventually determined to be malignant either by histopathology (n = 7) or by follow-up (n = 11). The remaining 32 lesions were proven or assumed to be benign by histopathology (n = 4) or clinical follow-up (n = 28). Unlike previously published reports, PET was interpreted as positive if the uptake was equal to or greater than that of the liver. RESULTS: No malignant lesion yielded a negative result on PET. Most lesions (13/18) showed significantly higher FDG uptake than that of the liver. In the remaining 5 lesions (2 metastases from neuroendocrine tumor, 2 early metastases, and 1 necrotic metastasis), FDG uptake was equal to or slightly higher than that of the liver. Of the 32 benign lesions, there were 2 lesions with uptake equal to or slightly higher than that of the liver, 3 with uptake less than the liver but more than the background, and 27 with uptake of the background. MRI identified 3 of the 13 lesions as false-positives but FDG PET correctly identified all 3 as benign. The other 10 adrenal lesions accurately diagnosed by MRI were also characterized by PET. FDG PET for characterization of adrenal lesions showed a sensitivity of 100%, a specificity of 94%, and an accuracy of 96%. CONCLUSION: FDG PET showed excellent diagnostic performance in differentiating adrenal lesions detected on CT or MRI. Because FDG PET has the additional advantage of evaluating the primary lesions as well as metastases, it could be cost-effective and the modality of choice for the characterization of adrenal lesions, especially in patients with malignancy.     

Extra-axillary nodal metastases in breast cancer: comparison of ultrasound,MRI, PET/CT,and CT

PurposeTo evaluate how ultrasound (US), MRI, PET/CT, and CT predict extra-axillary nodal metastases.Subjects and methodsThis IRB approved, retrospective study consisted of 124 suspicious supraclavicular and 88 internal mammary (IM) nodal cases with US and at least one additional cross-sectional examination (MRI, PET/CT or CT) from a total of 1472 invasive cancers with staging nodal US between January 2016–January 2019. Imaging findings were compared with the true node status, determined by fine needle aspirate (FNA) biopsy or evidence of response to chemotherapy on follow up imaging.ResultsIn the supraclavicular region, US had accuracy 98.2%, consisting of 97 true positives (TP), 27 false positives (FP), and 1348 true negative (TN). 93.5% of suspicious supraclavicular nodes had FNA for a PPV 78.2%. PET/CT had accuracy 88.6% (26 TP, 5 TN and 4 false negatives (FN)). CT exams had accuracy 61.7% (42 TP, 16 TN, 7 FP, and 29 FN).In the IM region, US had accuracy 93.2% (82 TP, 1 FP, 5 FN, and 1384 TN) but only 43.2% of suspicious IM nodes had FNA for a PPV 98.8%. MRI had accuracy 100.0% (all 47 TP). PET/CT exams had accuracy 96.8% (30 TP and 1FN). CT exams had accuracy 62.7% (36 TP, 1 TN, and 22 FN).ConclusionUS/FNA has accuracy 98.2% and 93.2% in the supraclavicular and IM regions, however only 43.2% of suspicious IM nodes are directly sampled. In these cases, MRI or PET/CT can be used to problem solve and guide treatment decisions.