Lesion regression rate based on RECIST: prediction of treatment outcome in patients with head and neck cancer treated with chemoradiotherapy compared with FDG PET-CT

The aim of this study was to evaluate whether the lesion regression rate (ΔLR) based on the Response Evaluation Criteria in Solid Tumors (RECIST) criteria could be used for the prediction of treatment outcome in head and neck squamous cell carcinoma (HNSCC) patients treated with chemoradiotherapy (CRT) compared with FDG PET-CT. A total of 33 patients underwent MRI and PET-CT at pretreatment and at 8 weeks after CRT. We assessed the treatment outcome by analyzing the following parameters: the RECIST criteria, ΔLR, the European Organization for Research and Treatment of Cancer (EORTC) criteria, and pretreatment SUV_max of the primary tumor and node. The correlation between the analysis of the parameters and the results of the long-term follow-up of the patients was determined. The RECIST did not significantly correlate with locoregional control (LRC) or survival. The ΔLR was significantly lower for the lesions with locoregional failure (LRF) than for those with LRC. A threshold ΔLR of 48% revealed a sensitivity of 72.7% and specificity of 77.3% for the prediction of LRF. Progression-free survival (PFS) of patients with ΔLR ≥ 48% was significantly better than that of patients with ΔLR < 48% (P = 0.001), but not overall survival. There was a significant correlation between LRC and the EORTC (P = 0.02). The patients who achieved a complete response by the EORTC criteria showed significantly better PFS and overall survival (P = 0.01 and 0.04, respectively). The ΔLR was inferior to FDG PET-CT with respect to the prediction of patient survival; however, it may be useful for selecting patients in need of more aggressive monitoring after CRT.     

PET-CT对肺癌纵隔淋巴结转移的诊断效能及相关影响因素的研究

目的 探究正电子发射计算机断层显像（PET-CT）对肺癌纵隔淋巴结转移的诊断效能,分析影响诊断效能的相关因素以及肺癌淋巴结转移的影响因素,为临床提供理论参考。方法 选取我院2019年1月—2020年12月收治的经手术病理证实的181例肺癌（476枚淋巴结）患者临床资料进行分析,均行PET-CT进行诊断,分析诊断的效能（灵敏度、特异性、准确性以及阳性/阴性预测值）;分析影响PET-CT诊断效能的因素,以及肺癌患者发生纵隔淋巴结转移的相关危险因素。结果 PET-CT诊断肺癌淋巴结转移的灵敏度65.75%（96/146）,特异性89.39%（295/330）,准确率82.14%（391/476）,阳性预测值73.28%（96/131）,阴性预测值85.51%（295/345）,同手术病理结果相比,差异无统计学意义（P > 0.05）。真阳性淋巴结与假阳性淋巴结的短径、SUVmax值相比较,差异均无统计学意义（P > 0.05）;真阳性淋巴结与假阳性淋巴结的密度相比,差异有统计学意义（P < 0.05）。经Logistic回模型分析分析显示,肿瘤的病理类型为腺癌、中央型肺癌、低分化程度是肺癌患者发生纵隔淋巴结转移的危险因素（P < 0.05）。结论 PET-CT诊断肺癌纵隔淋巴结转移有较高的灵敏度、特异性、准确性;诊断的灵敏度受淋巴结的短径与SUVmax值影响,诊断的特异性受淋巴结的密度影响。纵隔淋巴结转移主要与病理类型、病灶部位、分化程度有关。     

Imaging update on soft tissue sarcoma

Soft tissue sarcomas (STS) are rare tumours presenting as soft tissue lumps. Ultrasound is often the primary modality for the initial assessment, with MRI the mainstay for lesion characterisation. PET/CT along with other emerging MRI sequences are used in certain situations as an adjunct and problem solving tool in STS staging and assessment of disease recurrence. Recent advances include the promise of whole body MRI, hybrid PET/MRI, diffusion weighted imaging, dynamic contrast enhanced MRI and advances in artificial intelligence. This article discusses current concepts in extremity STS imaging and highlights recent advances.     

核医学检查受检者所受辐射剂量分析

目的 对核医学检查受检者所受辐射剂量进行测量和分析,以有效剂量表征受检者受到的辐射强度。方法 对核医学检查受检者进行分类,并测量计算所受放射性药物的辐射剂量,受检者所受计算机断层扫描(CT)辐射剂量,通过CT扫描参数和受检者信息等计算得到,上述两者相加换算得到受检者检查所受的有效剂量,并分析受检者所受辐射剂量的影响因素。结果 受检者正电子发射断层计算机成像(PET-CT)检查受到正电子放射性药物¹⁸F-氟代脱氧葡萄糖(¹⁸F-FDG)、¹⁸F-氟代胸苷(¹⁸F-FLT)、¹¹C-胆碱(¹¹C-choline)、¹¹C-蛋氨酸(¹¹C-MET)和¹¹C-乙酸盐(¹¹C-Ac)辐射所致有效剂量分别为(5.06±0.73)、(4.74±1.29)、(1.71±0.05)、(3.18±0.69)和(1.08±0.19)mSv;CT常规扫描辐射有效剂量为(8.80±0.58)mSv,若增加诊断CT扫描,接受的有效剂量可增大至27 mSv;单光子发射计算机断层成像(ECT)检查受到单光子放射性药物⁹⁹Tc^m-亚甲基二磷酸盐(⁹⁹Tc^m-MDP)、⁹⁹Tc^m-大颗粒聚合白蛋白(⁹⁹Tc^m-MAA)、⁹⁹Tc^m-二乙基三胺五乙酸(⁹⁹Tc^m-DTPA)、⁹⁹Tc^m-甲氧基异丁基异腈(⁹⁹Tc^m-MIBI)和⁹⁹Tc^m-焦磷酸盐(⁹⁹Tc^m-PYP)辐照所致的有效剂量分别为(4.63±0.01)、(1.71±0.01)、(1.18±0.01)、(7.19±0.03)和(4.18±0.01)mSv。结论 核医学检查受检者受到放射性药物辐射的有效剂量在1.08~7.19 mSv之间,PET-CT检查中CT所致有效剂量是8.80 mSv。     

FDG PET-CT combined with TBNA for the diagnosis of atypical relapsing polychondritis: report of 2 cases and a literature review

Objective

To explore the value of ¹⁸F-fluorodeoxyglucose positron emission tomography-computed tomography (FDG PET-CT) combined with transbronchial needle aspiration (TBNA) in diagnosing atypical relapsing polychondritis (RP).

Methods

Data from two patients with atypical RP, which had been diagnosed in our hospital using FDG PET-CT combined with TBNA, were retrospectively analyzed. A review of the relevant literature was also performed.

Results

Consistent with the previously reported 20 cases of RP that had been diagnosed using FDG PET-CT, the two patients in the present study showed the involvement of multiple organs, including the nose, throat, trachea, bronchi, costicartilage and joint cartilages, and increased FDG uptake was found in these areas. The mean value of SUVmax was 5.14. PET-CT revealed that 86.4% of the patients with RP had airway involvement. TBNA technique was used for biopsy of the hypermetabolic lesions, and pathologic examinations confirmed the diagnosis of RP. The time to diagnosis in these two patients and the 20 cases reported previously was about 6.9 months, significantly shorter than the average diagnosis time (20 months).

Conclusions

FDG PET-CT has several advantages for diagnosing RP, especially atypical RP. TBNA is a minimally invasive and safe technique for obtaining airway cartilage. Combining PET-CT with TBNA may play an important role in shortening the time to diagnosis in patients with RP involvement of airway.     

Positron emission tomography–computed tomography in the assessment of viability of femoral head in acetabular fractures

Purpose

The aim of this study was to use positron emission tomography–computed tomography (PET-CT) imaging as a tool for assessment of viability of femoral head in acetabular fractures and help in early detection of complications like avascular necrosis (AVN) of the femoral head.

Methods

In our study PET-CT was done pre-operatively and six weeks postoperatively in 31 patients who underwent open reduction and internal fixation (ORIF) of acetabular fractures and fracture–dislocations. There were 26 male and five female patients who were treated in our institute between January 2009 and July 2010. Patients were subsequently followed up with plain radiographs for a mean period of 3.8 years and minimum of two years.

Results

Although seven out of 31 patients showed avascularity of the femoral head on PET-CT in the pre-operative period, only two patients progressed to AVN at final follow up, whereas the other five patients regained the vascularity at the end of six weeks. There was no statistically significant correlation between vascular status on pre-operative scan and the presence of AVN on final follow-up radiograph. There was a significant correlation between avascularity of the femoral head on the sixth week PET-CT and AVN in the final radiograph.

Conclusion

PET-CT seems to be useful as a prognostic investigation in the assessment of the vascular status of the femoral head following injuries around the hip. Both pre-operative and postoperative imaging are necessary to understand the time-dependent changes in blood flow following injury.     

PET-CT 显像在卵巢恶性肿瘤淋巴结转移诊断中的临床价值

目的：探讨PET-CT显像对卵巢恶性肿瘤淋巴结转移的诊断价值。方法对52例卵巢恶性肿瘤患者（初治39例、复发13例）于手术前采用PET-CT检测预测腹膜后淋巴结转移状况及位置。初治患者行卵巢癌肿瘤细胞减灭术同时行腹膜后淋巴结清扫术,复发患者行病灶及区域淋巴结清扫术。将术前PET-CT检测结果与术后淋巴结病理检查结果进行对照,计算PET-CT检测诊断卵巢恶性肿瘤淋巴结转移的敏感性、特异性、准确性、阳性预测值和阴性预测值。结果 PET-CT显像诊断腹膜后淋巴结转移的敏感性、特异性、准确性、阳性预测值和阴性预测值分别为96．30％（26/27）、92．00％（23/25）、94．23％（49/52）、92．86％（26/28）和95．83％（23/24）;诊断腹主动脉旁淋巴结转移的敏感性、特异性、准确性、阳性预测值和阴性预测值分别为96．30％（26/27）、100．％（25/25）、98．08％（51/52）、100％（26/26）和96．15％（25/26）;诊断盆腔淋巴结转移的敏感性、特异性、准确性、阳性预测值和阴性预测值分别为90．91％（10/11）、95．12％（39/41）、94．23％（49/52）、83．33％（10/12）和97．50％（39/40）。结论 PET-CT在卵巢恶性肿瘤淋巴结转移诊断方面有较高的临床价值。