Spectrum of malignant pleural and pericardial disease on FDG PET/CT

OBJECTIVE: The purpose of this article is to illustrate a wide spectrum of malignant primary and secondary pleural and pericardial diseases imaged with (18)F-FDG PET/CT. CONCLUSION: A wide variety of malignant pleural and pericardial diseases can be detected, staged, and monitored by FDG PET/CT. Although the PET/CT findings are often nonspecific, the aim of this atlas is to show that the spectrum of pleural and pericardial disease that can be evaluated with PET/CT is much broader than current literature would suggest. PET/CT readers and oncologists should be aware of the wide variety of malignancies that can affect the pleura and pericardium and some of the patterns of FDG uptake that can be observed in these cases.     

18F-NaF PET/CT骨显像在甲状旁腺功能亢进性骨病中的应用

目的 探讨甲状旁腺功能亢进性骨病18F-NaF PET/CT骨显像的影像学特点及其应用价值。 方法 收集30例经临床及术后病理证实为甲状旁腺功能亢进症患者[男性11例、女性19例,年龄18～71（52.3±13.5）岁]的18F-NaF PET/CT骨显像及99Tcm -亚甲基二膦酸盐（99Tcm-MDP）全身骨显像资料,回顾性分析其18F-NaF PET/CT骨显像特点,对比两种骨显像方法对该病局部骨骼病灶的检出情况,并根据Mirels评分标准对棕色瘤进行评分。 结果 两种骨显像方法定性结果一致,即骨显像阴性15例,阳性15例。甲状旁腺功能亢进性骨病在18F-NaF PET图像上大部分表现为以全身多骨弥漫性骨代谢增高为主的多种代谢性骨病征象,并发棕色瘤、骨硬化及病理性骨折等时表现为单发或多发局灶性显像剂异常分布,其中棕色瘤表现为局灶性显像剂浓聚、显像剂稀疏或病灶中心显像剂分布缺损伴边缘显像剂不均匀浓聚;同机CT图像上均表现为全身多骨多种形式的骨质吸收,其中,表现为广泛骨质疏松13例、伴棕色瘤7例、骨质硬化6例、骨质软化3例、病理性骨折3例。15例甲状旁腺功能亢进性骨病患者共检出局部骨骼病灶（棕色瘤、骨硬化、病理性骨折、假骨折）53个,其中,18F-NaF PET/CT骨显像全部检出,99Tcm-MDP全身骨显像检出32个。7例甲状旁腺功能亢进性骨病患者伴棕色瘤,位于长骨的棕色瘤病灶数共24个,其中9个Mirels评分大于9分。 结论 甲状旁腺功能亢进性骨病在18F-NaF PET/CT骨显像上的全身骨代谢及解剖学表现有一定的特征性表现,18F-NaF PET/CT骨显像结合同机CT上全身骨骼病灶的详细信息,在甲状旁腺功能亢进性骨病的诊断、鉴别诊断及病情严重程度评估中有更好的应用价值。     

FDG PET/CT findings in recurrent malignant schwannoma

Malignant schwannoma is an uncommon but aggressive sarcoma that most commonly arises in young and middle-aged adults. We present a 28-year-old male patient with a recurrent chest wall malignant schwannoma. An FDG PET/CT was performed to evaluate the management of the patient. The PET/CT images showed hypermetabolic mass lesions in the left upper chest wall and increased FDG uptake in the left axillary region. The pathologic results confirmed the PET findings. We conclude that FDG PET/CT could play an important role in the staging, restaging, and post-therapy follow-up of malignant schwannomas.     

PET/CT in malignant melanoma: contrast-enhanced CT versus plain low-dose CT

Purpose  

The aim of this study was to evaluate the diagnostic value of contrast-enhanced CT (CECT) versus non-enhanced low-dose CT (NECT) in the staging of advanced malignant melanoma with ¹⁸F-fluordeoxyglucose (FDG) positron emission tomography (PET)/CT.     

Role of PET/CT in malignant pediatric lymphoma

Introduction

Malignant pediatric lymphoma accounts for 10–15% of all pediatric cancers, (representing 2–3% of all malignancies), with a peak incidence between 5–9 years. Chemotherapy is usually the first and most common mode of treatment. The choice of treatment and prediction of prognosis depend on the histological type of tumor, initial staging, evaluating treatment response, and detection of early recurrence. Conventional imaging modalities have many limitations. PET/CT is more accurate, however so far the literature lacks the results of a large group of patients.

Aim of study

To report the role of PET/CT in the above-mentioned objectives at the newly established Children’s Cancer Hospital in Cairo, Egypt, which is one of the busiest dedicated pediatric oncology centers of such purposes in the world. All findings were proven by histopathology, clinically, and by clinical follow-up.

Patient population

A total of 152 patients (35 girls and 117 boys) with histologically proven malignant lymphoma (117 HD, 35 NHL) were included in this study. They were divided into four groups. Group I: 41 patients for initial staging. Group II: 51 patients for evaluating early treatment response after two to three cycles of chemotherapy. Group III: 42 patients for evaluating treatment response 4–8 weeks after the end of their treatment. Group IV: 18 patients evaluated for long-term follow-up. Results of PET/CT were compared with the other conventional imaging modalities (CIM).

Results

The sensitivity, specificity, accuracy, and positive and negative predictive values of PET/CT and CIM were as follows: In Group I: PET/CT modified staging and treatment in 11 out of 41 cases (26.8%), upstaged 5(12.2%) patients and down-staged six (14.6%) patients. Group II: 100%, 97.7%, 98%, 85.7%, 100%, respectively, for PET/CT and 83%, 66.6%, 68.6%, 25%, 96.7% for CIM respectively Group III: At the end of chemotherapy 100%, 90.9%, 92.8%, 75%, 100%, respectively, for PET/CT and 55.5%, 57.5%, 57.1%, 26.3%, 82.6% for CIM, respectively. Group IV: For long-term follow-up, all the parameters scored 100% for PET/CT, 100%, 38.4%, 72.2%, 50%, 100% for CIM, respectively.

Conclusion

PET/CT in pediatric lymphoma is more accurate than CIM. We recommend that it should be the first modality for all purposes in initial staging, evaluating treatment response and follow-up.     

Assessment of malignant skeletal disease: initial experience with 18F-fluoride PET/CT and comparison between 18F-fluoride PET and 18F-fluoride PET/CT.

18F-fluoride PET/CT was performed on 44 oncologic patients to evaluate its diagnostic accuracy in assessing malignant osseous involvement and in differentiating malignant from benign bone lesions. METHODS: (18)F-fluoride PET and (18)F-fluoride PET/CT were interpreted separately. Lesions showing increased (18)F-fluoride uptake were categorized as malignant, benign, or inconclusive. The final diagnosis of lesions was based on histopathology, correlation with contemporaneous diagnostic CT or MRI, or clinical follow-up of at least 6 mo (mean, 10 +/- 3 mo). RESULTS: Increased (18)F-fluoride uptake was detected at 212 sites, including 111 malignant lesions, 89 benign lesions, and 12 lesions for which the final diagnosis could not be determined. In a lesion-based analysis, the sensitivity of PET alone in differentiating benign from malignant bone lesions was 72% when inconclusive lesions were considered false negative and 90% when inconclusive lesions were considered true positive. On PET/CT, 94 of 111 (85%) metastases presented as sites of increased uptake with corresponding lytic or sclerotic changes, and 16 of the 17 remaining metastases showed normal-appearing bone on CT, for an overall sensitivity of 99% for tumor detection. For only 1 metastasis was PET/CT misleading, suggesting the false diagnosis of a benign lesion. The specificity of PET/CT was significantly higher than that of PET alone (97% vs. 72%, P < 0.001). PET/CT identified benign abnormalities at the location exactly corresponding to the scintigraphic increased uptake for 85 of 89 (96%) benign lesions. In a patient-based analysis, the sensitivity of PET and PET/CT was 88% and 100%, respectively (P < 0.05) and the specificity was 56% and 88%, respectively (not statistically significant). Among the 12 patients referred for (18)F-fluoride assessment because of bone pain despite negative findings on (99m)Tc-methylene diphosphonate bone scintigraphy, (18)F-fluoride PET/CT suggested malignant bone involvement in all 4 patients with proven skeletal metastases, a potential benign cause in 4 of 7 patients who had no evidence of metastatic disease, and a soft-tissue tumor mass invading a sacral foramen in 1 patient. CONCLUSION: The results indicate that (18)F-fluoride PET/CT is both sensitive and specific for the detection of lytic and sclerotic malignant lesions. It accurately differentiated malignant from benign bone lesions and possibly assisted in identifying a potential cause for bone pain in oncologic patients. For most lesions, the anatomic data provided by the low-dose CT of the PET/CT study obviates the performance of full-dose diagnostic CT for correlation purposes.     

PET/CT在儿科恶性肿瘤中的应用进展

自PET/CT进入临床以来,主要应用于成人肿瘤的良恶性鉴别、原发灶寻找、临床分期和再分期、疗效评估、指导手术和放化疗计划以及预测生存期等方面,在儿童中的应用相对较少。从国内外相关的文献来看,PET/CT在国内儿科肿瘤诊断中的应用与国外有一定的差距。究其原因,主要与医用放射性核素知识的普及程度低,以及临床对PET/CT在儿科恶性肿瘤中的应用认知度不够相关,以致国内儿科PET/CT工作开展少,缺乏经验,从而形成一种恶性循环。该文主要从以上两方面分别进行阐述,希望促进PET/CT在儿科恶性肿瘤中的应用。     

Syphilitic bone destruction on FDG PET/CT

A 35-year-old man underwent PET/CT scan to evaluate suspected osseous metastases from a presumed tumor of unknown origin. PET images demonstrated multiple foci of increased FDG uptake in all extremities, corresponding to the osseous destruction on the concurrent CT images. However, no primary tumor was identified. Instead, the bone lesions were subsequently proven due to syphilis infection.     

18F-FDG PET/CT显像诊断心包恶性病变的价值

目的 评价18F-脱氧葡萄糖（FDG）PET/CT对心包恶性病变的诊断价值.方法 对23例心包积液患者进行18F-FDG PET/CT显像,并采用两独立样本非参数检验分析良恶性病灶最大标准摄取值（SUVmax）差异有无统计学意义.结果 经病理检查证实恶性心包积液14例,良性心包积液9例.1例PET/CT假阴性,2例PET/CT假阳性.18F-FDG PET/CT鉴别诊断良恶性心包积液的灵敏度、特异性、准确性、阳性预测值、阴性预测值分别为92.9%（13/14）、7/9、87.0%（20/23）、86.7%（13/15）和7/8.良、恶性病变的SUVmax中位值分别为2.2和6.0,两者间比较差异有统计学意义（z=-3.279,P=0.001）.结论 18F-FDG PET/CT是评价心包恶性病变较好的无创性手段,对良恶性心包积液的诊断与鉴别诊断有一定临床价值.     

18F-FDG PET/CT显像诊断心包恶性病变的价值

Objective To assess the value of integrated 18 F-fluorodeoxyglucose (FDG) PET/CT in differentiation of malignant and benign pericardial effusion. Methods 18F-FDG PET/CT were performed in 23 patients with pericardial effusion. The detected soft tissue tumor or nodulous lession in pericardium or the thickened pericardium, with the maximum standardized uptake value( SUVmax ) ≥2.5, was defined as PET/CT-positive. The invaded lession in pericardium with SUVmax ≥2.5 was also as the positive. The difference of SUVmax of benign and malignant lesions was analyzed with two-independent-sample test of nonparametric tests. The final diagnosis was confirmed by biopsy or post-operative pathology. Results The diagnosis were confirmed with 14 malignant and 9 benign lesions. The median of SUVmax was 6.0 in malignancy group and 2.2 in benign group (z= -3. 279, P =0.001 ). According to the pathology results, there were one false negative case and two false positive cases with PET/CT imaging interpretation. The sensitivity, specificity,accuracy, positive predictive value ( PPV ) and negative predictive value ( NPV ) of 18 F-FDG PET/CT in diagnosis of benignity or malignance of pericardium effusion were 92.9% ( 13/14), 7/9, 87.0% (20/23),86.7% (13/15) and 7/8, respectively. Conclusion For the patients with pericardium effusion 18F-FDG PET/CT may be a helpful modality for malignancy differentiation     

PET/CT和PET/MR在黑色素瘤中的临床应用及新进展

黑色素瘤易转移、复发率高,已经成为严重危及人民健康的恶性肿瘤之一,早期诊断和准确分期对预后及远期生存十分关键。18F-FDG PET/CT作为一项集PET与CT于一体的成像模式,被广泛地应用于包括黑色素瘤等在内的恶性肿瘤的诊断、分期及疗效的评估。随着一体化PET/MR成像系统研发的成功,多模态成像技术向前迈进了一大步,实现了真正意义上的数据同步采集。笔者就18F-FDG PET/CT及PET/MR在黑色素瘤分期、复发和疗效评价中的研究现状进行综述,介绍了多模态成像技术在黑色素瘤中的新进展。     

18F-FDG PET/CT in a recurrent diffuse malignant peritoneal mesothelioma

Peritoneal mesothelioma is a rare and aggressive tumor. Early diagnosis of the disease is difficult, delaying effective treatment. We report a case of recurrent, biphasic, diffuse, malignant peritoneal mesothelioma. Initial abdominal computed tomography showed abnormal but nonspecific findings suggestive of an ovarian malignancy, with a negative endoscopy and laboratory studies. An abdominal exploratory laparotomy found widespread malignancy within the peritoneum with a pathological diagnosis of peritoneal mesothelioma. A PET/CT imaging showed diffusely increased metabolic activity throughout the peritoneum, with no evidence of thoracic or pleural involvement. This case demonstrates the PET/CT findings seen with malignant recurrent peritoneal mesothelioma.     

骨淋巴瘤的~(18)F-FDG PET/CT表现

目的探讨骨淋巴瘤18F-FDG PET/CT显像的影像学特点。方法搜集经病理组织学证实的骨淋巴瘤患者35例,其中原发性骨淋巴瘤4例,继发性骨淋巴瘤31例,分析其18F-FDG PET/CT表现。结果 4例原发性骨淋巴瘤均为非霍奇金淋巴瘤,单骨发病,表现为骨质破坏伴软组织肿块,放射性摄取增高,SUVmax 7.9~17.9。31例继发性骨淋巴瘤,霍奇金淋巴瘤5例,非霍奇金淋巴瘤26例,单骨发病2例,多骨发病29例,骨质密度异常表现多样,具体分为:(1)骨质破坏型20例,表现为不同程度溶骨性骨质破坏,邻近可伴或不伴有软组织肿块,放射性摄取不同程度增高,SUVmax 2.5~15.0;(2)骨质硬化型3例,以骨质硬化为主,病变区域骨质密度高于正常骨骼,不伴有邻近的软组织肿块影;放射性摄取无异常增高或轻度增高,SUVmax 1.0~5.6;(3)骨髓浸润型8例,全身骨髓弥漫性放射性摄取增高,SUVmax 1.7~9.8,无骨质密度异常。结论骨淋巴瘤18F-FDG PET/CT影像学表现有一定的特征性,分析其表现,对原发性和继发性骨淋巴瘤的诊断、鉴别诊断有重要的临床价值。     

Dual-time point PET/CT with F-18 FDG for the differentiation of malignant and benign bone lesions

Purpose  The purpose of the present study was to evaluate whether 2-fluoro[fluorine-18]-2-deoxy-d-glucose (F-18 FDG) positron emission tomography (PET) could differentiate malignant and benign bone lesions and whether obtaining delayed F-18 FDG PET images could improve the accuracy of the technique. Methods  In a prospective study, 67 patients with bone lesions detected by computed tomography (CT) or magnetic resonance imaging were included. Whole body PET/CT imaging was performed at 1 h (early) after the F-18 FDG injection and delayed imaging at 2 h post injection was performed only in the abnormal region. Semiquantitative analysis was performed using maximum standardized uptake value (SUV_max), obtained from early and delayed images (SUV_maxE and SUV_maxD, respectively). The retention index (RI) was calculated according to the equation: RI = (SUV_maxD − SUV_maxE) × 100/SUV_maxE. Histopathology of surgical specimens and follow-up data were used as reference criteria. The SUV_maxE and RI were compared between benign and malignant lesions. Results  The final diagnoses revealed 53 malignant bone lesions in 37 patients and 45 benign lesions in 30 patients. There were statistically significant differences in the SUV_maxE between the malignant and benign lesions (P = 0.03). The mean SUV_maxE was 6.8 ± 4.7 for malignant lesions and 4.5 ± 3.3 for benign lesions. However, a considerable overlap in the SUV_maxE was observed between some benign and malignant tumors. With a cutoff value of 2.5 for the SUV_maxE, the sensitivity, specificity, and accuracy were 96.0%, 44.0%, and 72.4%, respectively. The positive predictive value (PPV) and negative predictive value (NPV) were 67.1% and 90.9%, respectively. There were significant differences in the RI between the malignant and benign lesions (P = 0.004). But there was overlap between the two groups. The mean RI was 7 ± 11 for the benign lesions and 18 ± 11 for the malignant lesions. When an RI of 10 was used as the cutoff point, the sensitivity, specificity, and accuracy were 90.6%, 76.0%, and 83.7.0%, respectively. The PPV and NPV were 81.4% and 87.1%, respectively. Conclusions  The results of this study indicate that dual-time point F-18 FDG PET may provide more help in the differentiation of malignant tumors from benign ones.     

68Ga-FAPI PET/CT在恶性肿瘤中的临床应用

成纤维细胞激活蛋白（FAP）作为肿瘤相关成纤维细胞（CAFs）的分子标志物之一,在激活的CAFs中高度特异性表达。FAP具有促进肿瘤侵袭、转移和免疫逃逸的作用,可作为恶性肿瘤诊疗的重要靶点。镓-68标记的FAP抑制剂（ 68Ga-FAPI）是基于FAP合成的小分子探针,经PET/CT显像可实现FAP在体内的可...