头颈部肿瘤放疗过程中腮腺变化对照射剂量影响的研究

目的 分析头颈部肿瘤患者螺旋断层放疗过程中腮腺位置、体积变化对受照剂量的影响.方法 12例头颈部肿瘤根治性放疗患者,每次治疗前行MVCT图像配准,选择每周第1天MVCT图像,应用TomoTherapy系统自带软件和MIM系统,计算腮腺体积、位置变化和实际照射剂量.结果 与初始计划相比,放疗结束时左、右两侧腮腺体积分别缩小29.06%和31.78%(Z=6.77、3.06,P<0.05),腮腺质心距离体中线距离分别缩小6.72%和6.19%(t=5.14、5.80,P<0.05).治疗过程中左侧腮腺V₂₆、平均剂量分别增加37.74%、25.08%(Z=-6.03、-5.31,P<0.05),右侧腮腺V₂₆、平均剂量分别增加30.45%、19.33%(Z=-5.43、-3.26,P<0.05).结论 头颈部肿瘤放疗过程中腮腺实际受照剂量较初始计划明显升高,剂量升高与腮腺向体中线位移密切相关,与腮腺体积缩小无明显相关性.适时重新制定放疗计划或行自适应放疗,可减少腮腺受照剂量.     

老年头颈癌患者125I粒子植入治疗后的生存质量研究

目的 评价老年头颈癌患者碘-125(¹²⁵I)粒子植入治疗后生存质量状况。方法 选择2005年至2011年就诊于本院因头颈癌行¹²⁵I粒子植入治疗的老年患者40例,采用QOL-RTI问卷对生存质量进行调查。评价其生存质量情况,并分析治疗后影响生存质量的因素。结果 40例入选患者,治疗后维持了良好的生存质量。老年舌根癌患者粒子植入后生存质量低于其他部位癌患者;老年患者功能状况和整体生存质量随年龄增加而降低;术后辅助¹²⁵I粒子植入治疗患者生存质量(QOL)高于未能完全切除或难以手术的患者;病理类型、粒子植入数量以及治疗后时长对患者生存质量无明显影响。结论 老年头颈癌患者行¹²⁵I粒子植入术后,维持有良好的生存质量。肿瘤靶区和临床分期是影响患者生存质量的重要因素。     

Posttreatment imaging in head and neck cancer

Posttreatment imaging is done when a recurrent tumour is suspected, to confirm the presence of such a lesion and to determine its extent. The extent of a recurrent cancer is important information for determining the possibility of salvage therapy. Imaging may also be used to monitor tumour response and to try to detect recurrent or persistent disease before it becomes clinically evident, possibly with a better chance for successful salvage. This article reviews the expected imaging findings after treatment of head and neck squamous cell cancer, and how to differentiate these from persistent or recurrent cancer. The relative value of anatomical and biological imaging modalities, including newer techniques such as diffusion-weighted magnetic resonance imaging, is addressed. The imaging findings in treatment-induced complications, such as tissue necrosis, sometimes difficult to differentiate from cancer, are explained.     

Assessment of cervical lymph node metastases using FDG-PET in patients with head and neck cancer

OBJECTIVE: To evaluate the diagnostic accuracy of fluorodeoxyglucose positron emission tomography (FDG-PET) relative to computed tomography (CT) for detecting metastatic cervical lymph nodes in patients with squamous cell carcinoma of the head and neck (HNSCC), and to ascertain the factors that affect this accuracy. METHODS: A total of 1076 lymph nodes obtained from 35 neck dissections in 26 HNSCC patients who preoperatively underwent both FDG-PET and CT were retrospectively analyzed. For pathological metastatic lymph nodes, the lymph node size (short-axis diameter), the ratio of intranodal tumor deposits, and the size of intranodal tumor deposits (maximum diameter of metastatic foci in each lymph node) were histologically recorded. RESULTS: Forty-six lymph nodes from 23 neck sides were pathologically diagnosed metastases. The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of FDG-PET evaluated individually per neck side were 74%, 92%, 80%, 94%, and 65%, respectively, whereas those of CT were 78%, 58%, 71%, 78%, and 58%, respectively. FDG-PET detected 100% of metastatic lymph nodes > or =10 mm, intranodal tumor deposits > or =9 mm, and intranodal tumor deposits with a ratio >75%, whereas no nodes or tumor deposits smaller than 5 mm were detected. The spatial resolution limitations of FDG-PET were responsible for 16 of 20 (80%) false-negative PET results in lymph nodes. CONCLUSIONS: FDG-PET is a useful tool for preoperative evaluation of the neck because it accurately detects metastatic lymph nodes > or =10 mm and has fewer false-positive cases than CT. The high specificity of FDG-PET for lymph node metastases may play an important role in avoiding unnecessary neck dissection.     

MR imaging of the head and neck

The purpose of this paper is to describe current imaging protocols for MR imaging of the head and neck region and to define results and clinical impact. Depending on the clinical question, different MRI protocols are presented for imaging of the head and neck. The appearance of different pathologic findings on imaging studies and how adapted imaging protocols help to improve differential diagnosis is discussed. In summary, MRI is the method of choice for imaging of the head and neck.     

TNM staging with FDG-PET/CT in patients with primary head and neck cancer

Purpose PET/CT, PET+CT, and CT were compared concerning accuracies in TNM staging and malignancy detection in head and neck cancer. The impact of PET/CT compared to the other imaging modalities on therapy management was assessed. Materials and methods Fifty-five patients with suspected head and neck primary cancer underwent whole-body FDG-PET/CT. PET/CT and PET+CT were evaluated by a nuclear medicine physician and a radiologist; CT was evaluated by two radiologists, PET by two nuclear physicians. Histopathology served as the standard of reference. Differences between the staging modalities were tested for statistical significance by McNemar’s test. Results Overall TNM-staging and T-staging with PET/CT were more accurate than PET+CT and CT alone (p < 0.05). PET/CT was marginally more accurate than CT alone in N-staging (p = 0.04); no statistically significant difference was found when compared to PET+CT for N-staging. PET/CT altered further treatment in 13 patients compared to CT only and in 7 patients compared to PET+CT. Conclusion Combined PET/CT proved to be partly more accurate in assessing the overall TNM-stage than CT and PET+CT. These results were based on a higher accuracy concerning the T-stage, mainly in patients with metallic implants and marginally the N-stage. Therapy decisions have been influenced in a substantial number of patients. PET/CT might be considered as a first line diagnostic tool in patients with suspected primary head and neck cancer.     

99Tcm-MIBI显像在头颈部恶性肿瘤中的应用

99Tcm-MIBI(99Tcm-sestamibi)作为亲肿瘤显像剂,对头颈部恶性肿瘤及其颈部淋巴结转移、邻近颅骨受累的诊断有较高的灵敏度、特异性和准确性,在头颈部肿瘤的诊断和分期等方面有良好的应用前景.     

BNCT for advanced or recurrent head and neck cancer

The therapeutic effect of surgery and/or combination of conventional chemoradiotherapy is limited in the patients with recurrent squamous cell carcinoma (SCC) and locally advanced non-squamous cell carcinoma without malignant melanoma (non-SCC) of the head and neck. Currently, clinical trials of BNCT for head and neck cancers are being conducted in some institutes to verify its the effectiveness. BNCT was performed in 10 patients with recurrent SCC, 7 patients with recurrent non-SCC and 3 patients with newly diagnosed non-SCC in our university between October 2003 and September 2007. Eleven patients showed complete remission and 7 patients showed partial remission of irradiated site. The effective rate [(CR+PR)/total cases] was 90%. No severe acute or chronic normal-tissue reactions were observed in any patients. BNCT is effective and safe in the patients with recurrent SCC and locally advanced non-SCC.     

FDG-PET delayed imaging for the detection of head and neck cancer recurrence after radio-chemotherapy: comparison with MRI/CT

In advanced head and neck cancer, an organ-sparing approach comprising radiation therapy combined with intra-arterial chemotherapy has become an important technique. However, the high incidence of residual masses after therapy remains a problem. In this study, we prospectively evaluated the use of 2-[¹⁸F]fluoro-2-deoxy-d-glucose positron emission tomography (FDG-PET) delayed imaging for the detection of recurrence of head and neck cancer after radio-chemotherapy, and compared the FDG-PET results with those of magnetic resonance imaging (MRI) or computed tomography (CT). Forty-three lesions from 36 patients with head and neck cancer suspected to represent recurrence after radio-chemotherapy (median interval from therapy, 4 months) were studied. PET was performed at 2 h after FDG injection, and evaluated. The results were compared to those of contrast studies with MRI or CT performed within 2 weeks of the PET study, and to histological diagnosis (in all patients suspected of having recurrence) or clinical diagnosis. The lesion-based sensitivity (visual interpretation) and negative predictive value of FDG-PET (88% and 91%, respectively) were higher than those of MRI/CT (75% and 67% respectively). The specificity, accuracy and positive predictive value of FDG-PET (78%, 81% and 70%, respectively) were significantly (P<0.05) higher than those of MRI/CT (30%, 47% and 39% respectively). Three of six patients with false positive findings had post-therapy inflammation. Receiver operating characteristic (ROC) analysis showed that retrospective evaluation with the standardised uptake ratio yielded the best results (sensitivity 87.5%, specificity 81.5%), followed by visual interpretation and then the tumour/neck muscle ratio. An FDG-PET delayed imaging protocol yielded significantly better results for the detection of recurrence of head and neck cancer after radio-chemotherapy than MRI/CT. Because of the high negative predictive value of FDG-PET (91.3%), if PET is negative, further invasive procedures may be unnecessary.     

Cross-sectional imaging in non-melanoma skin cancer of the head and neck

AIM: To investigate in head and neck non-melanoma skin cancers (NMSCs) the accuracy of cross-sectional imaging for detection of local tumour extent, recurrent tumour and prediction of patient outcome. METHODS: This retrospective study included 33 NMSC patients (22 men, 11 women, median age 69 years) with 8 primary and 25 suspected recurrent tumours. The findings of magnetic resonance imaging (MRI) and computed tomography (CT) were compared with histopathology, and accuracy of MRI or CT in detecting local recurrence was determined. Extent of disease on imaging was compared with patient outcome assessed by clinical follow-up to a mean of 26.4 months. RESULTS: Lesions were identified in 29 patients, whose mean disease-free survival (DFS) was 25.5 months. In 4 of these cases, where imaging showed no invasion of deep structures, DFS was 56 months. In the other 25 cases DFS was 20.6 months, irrespective of treatment but varying with site of involvement. Of 19 patients treated with surgery, imaging of 16 showed deep invasion, which was confirmed at histology in 15 (93.7% accuracy), and 3 had superficial tumours on imaging all confirmed by histology (100% accuracy). Imaging accuracy for identifying recurrent tumour was 96% (24 of 25 patients). CONCLUSION: In NMSC, cross-sectional imaging accurately identifies tumour extent and local recurrence. The extent of disease and invasion of deeper structures predicts patient outcome.     

~(99m)Tc标记annexin V类显像剂细胞凋亡显像在肿瘤研究中的应用及进展

细胞凋亡在肿瘤的发生发展过程中起着重要的作用,成功的肿瘤治疗将在肿瘤组织内诱导肿瘤细胞产生凋亡。99mTc标记annexin V类显像剂凋亡显像能够在体内早期、无创伤性地检测到治疗所引起的细胞凋亡,这将有助于早期评判肿瘤患者的治疗效果及预后。     

Experience of high-dose-rate brachytherapy for head and neck cancer treated by a customized intraoral mold technique

Radiotherapy of head and neck cancer has become more successful with the advances in treatment modalities and use of a multidisciplinary approach. Higher quality treatment and a team approach to radiotherapy have thus been required for head and neck cancer. This study presents the clinical experience of high-dose-rate (HDR) brachytherapy for head and neck cancer treated by a customized intraoral mold technique. Two patients are reported for whom we created dental prostheses as the radiation carriers for HDR brachytherapy of their head and neck cancers. HDR brachytherapy with the dental prostheses reported here was feasible and effective for eradicating the head and neck cancer. It has been demonstrated that HDR brachytherapy using a customized intraoral technique can be a treatment option for patients who are not candidates for surgery or external irradiation. It is strongly suggested that specialized dentists are needed who are familiar with not only the anatomy and function of the head and neck region but also radiotherapy. Dental radiologists should take responsibility for constructing irradiation prostheses. If they do, they have the potential to improve the quality of life of patients who undergo radiotherapy for head and neck cancer.     

头颈部肿瘤放射性甲状腺功能减退的研究现状

放疗是头颈部肿瘤重要的治疗手段,由于解剖结构复杂,放疗时甲状腺难免会受到照射,照射造成的放射性甲状腺功能减退（RIHT,radiation-induced hypothyroidism,放射性甲减）及其对身体机能的影响逐渐引起人们关注。本文就头颈部肿瘤RIHT的临床特点、发生机制、危险因素、预测模型、评估及治疗等进行综述。     

MR spectrsocopy of head and neck cancer

The aim of this review is to discuss the technique and potential applications of magnetic resonance spectroscopy (MRS) in head and neck cancer. We illustrate the technical issues related to data acquisition, post processing and interpretation of MRS of head and neck lesions. MRS has been used for differentiation of squamous cell carcinoma from normal tissue. The main potential clinical application of proton MRS (¹H-MRS) is monitoring patients with head and neck cancer undergoing therapy. Pretreatment prediction of response to therapy can be done with phosphorus MRS (³¹P-MRS). Although performance of MRS of head and neck is challenging, technological advances in both software and hardware has the potential to impact on the clinical management of patients with head and neck cancer.     

Characterization of head and neck lesions with diffusion-weighted MR imaging and the apparent diffusion coefficient values

Purpose

The aim of this study was to determine the role of diffusion-weighted MR imaging (DWI) and the apparent diffusion coefficient (ADC) in characterization of head and neck lesions.

Patients and methods

MR imaging including diffusion-weighted sequences was performed on 43 patients presented with head and neck lesions. Images were obtained with a diffusion-weighted factor (b factor) of 100, 500, and 1000 s/mm². ADC maps were reconstructed, and the ADC value of the lesions was calculated.

Results

The mean ADC value of malignant tumors was (1.02 ± 0.22) × 10⁻³ mm²/s (n = 31). The mean ADC value of benign tumors was (1.62 ± 0.27) × 10⁻³ mm²/s (n = 12). The mean ADC of lymphomas was significantly lower than that of carcinomas. The difference in the ADC value between the malignant tumors and benign lesions was statistically significant (p < 0.001). Selection of (1.2) × 10⁻³ mm²/s as a threshold value of ADC for differentiating benign from malignant tumors yielded the best result, with an accuracy of 94%, sensitivity of 95%, specificity of 92%, positive predictive value of 92% and negative predictive value of 94%.

Conclusion

DWI and the ADC measurement are promising, non-invasive imaging approach that can be used for characterization of head and neck lesions. It can help differentiate malignant tumors from benign lesions.     

头颈部肿瘤涎腺放射性损伤的防治研究进展

放射性涎腺损伤是头颈部肿瘤患者放射治疗后最常见的并发症之一,表现为口腔疼痛,说话、吞咽困难等症状,严重影响患者的生存质量。因此,涎腺放射性损伤的防治十分重要。本文从放疗保护药物、放疗技术、分子生物学等方面,针对头颈部肿瘤涎腺放射性损伤的预防与治疗予以综述。     

Characterization of pediatric head and neck masses with diffusion-weighted MR imaging

We aimed to assess the clinical usefulness of the ADCs calculated from diffusion-weighted echo-planar MR images in the characterization of pediatric head and neck masses. This study included 78 pediatric patients (46 boys and 32 girls aged 3 months–15 years, mean 6 years) with head and neck mass. Routine MR imaging and diffusion-weighted MR imaging were done on a 1.5-T MR unit using a single-shot echo-planar imaging (EPI) with a b factor of 0.500 and 1,000 s mm⁻². The ADC value was calculated. The mean ADC values of the malignant tumours, benign solid masses and cystic lesions were (0.93 ± 0.18) × 10⁻³, (1.57 ± 0.26) × 10^–3 and (2.01 ± 0.21 )× 10^–3 mm² s⁻¹, respectively. The difference in ADC value between the malignant tumours and benign lesions was statistically significant (p < 0.001). When an apparent diffusion coefficient value of 1.25 × 10^–3 mm² s⁻¹ was used as a threshold value for differentiating malignant from benign head and neck mass, the best results were obtained with an accuracy of 92.8%, sensitivity of 94.4%, specificity of 91.2%, positive predictive value of 91% and negative predictive value of 94.2%. Diffusion-weighted MR imaging is a new promising imaging approach that can be used for characterization of pediatric head and neck mass.