Diagnosis of Recurrent Uterine Cervical Cancer: Computed Tomography versus Positron Emission Tomography

Objective

To determine the accuracy of CT and positron emission tomography (PET) in the diagnosis of recurrent uterine cervical cancer.

Materials and Methods

Imaging findings of CT and PET in 36 patients (mean age, 53 years) in whom recurrent uterine cervical cancer was suspected were analyzed retrospectively. Between October 1997 and May 1998, they had undergone surgery and/or radiation therapy. Tumor recurrence was confirmed by pathologic examination or follow-up studies.

Results

In detecting recurrent uterine cervical cancer, the sensitivity, specificity, and accuracy of CT were 77.8%, 83.3%, and 80.5%, respectively, while for PET, the corresponding figures were 100%, 94.4%, and 97.2%. The Chi-square test revealed no significant difference in specificity (p = .2888), but significant differences in sensitivity (p = .0339) and accuracy (p = .0244).

Conclusion

PET proved to be a reliable screening method for detecting recurrent uterine cervical cancer, but to determine the anatomical localization of recurrent tumors, and thus decide an adequate treatment plan, CT was eventually needed.     

F-18 Sodium Fluoride Positron Emission Tomography/Computed Tomography for Detection of Thyroid Cancer Bone Metastasis Compared with Bone Scintigraphy

Objective

The aim of the study was to compare the diagnostic performances of F-18 sodium fluoride positron emission tomography/computed tomography (bone PET/CT) and bone scintigraphy (BS) for the detection of thyroid cancer bone metastasis.

Materials and Methods

We retrospectively enrolled 6 thyroid cancer patients (age = 44.7 ± 9.8 years, M:F = 1:5, papillary:follicular = 2:4) with suspected bone metastatic lesions in the whole body iodine scintigraphy or BS, who subsequently underwent bone PET/CT. Pathologic diagnosis was conducted for 4 lesions of 4 patients.

Results

Of the 17 suspected bone lesions, 10 were metastatic and 7 benign. Compared to BS, bone PET/CT exhibited superior sensitivity (10/10 = 100% vs. 2/10 = 20%, p = 0.008), and accuracy (14/17 = 82.4% vs. 7/17 = 41.2%, p < 0.025). The specificity (4/7 = 57.1%) of bone PET/CT was not significantly different from that of BS (5/7 = 71.4%, p > 0.05).

Conclusion

Bone PET/CT may be more sensitive and accurate than BS for the detection of thyroid cancer bone metastasis.     

正电子发射计算机断层显像在精神疾病中的应用研究及进展

精神疾病是一类功能性脑疾病,其发病率的不断增加而受到日益关注.选择合适的研究方法对精神疾病进行发病机制、诊断治疗的研究已成为医学研究的热点课题.正电子发射型计算机断层显像以其反映组织细胞血流、代谢、受体密度等分子功能显像的特点在精神疾病研究领域中发挥着独特的作用,尤其在脑神经递质和受体显像方面具有其他非侵入性影像学检查方法所无可比拟的优势.     

PET与戒毒研究

药品依赖或称成瘾,近年来被认为是一种慢性脑病,以对特定神经活性药物或行为有耐受、渴求和戒断症状为特征,伴有精神与行为异常.成瘾有个人、社会和物质等几方面的基础.PET通过成瘾脑机制、受损脑区功能改变、成瘾易感性、复吸和治疗监测等方面对成瘾进行研究.与其他技术配合,PET以神经递质的受体、转运体、贮存囊泡、前体、相关酶、血流、葡萄糖代谢和标记成瘾物质作为显像剂,在揭示成瘾物质代谢,以多巴胺、血清紧张素、苯二氮( )等神经递质系统为中心的脑受体系统,以及其"下游"脑功能改变方面有独特的功效.今后,在结合精确解剖信息、发展更特异示踪剂和脑激活检查技术等进步基础上,PET可能会有力推动成瘾与成瘾治疗的研究水平.     

18F-FDG PET/CT Findings in a Breast Cancer Patient with Concomitant Tuberculous Axillary Lymphadenitis

Although ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) positron emission tomography (PET) is a sensitive modality for detecting a malignant lesion, increased ¹⁸F-FDG uptake is also seen in infected or inflammatory processes. Here, we report the case of a breast cancer patient with concomitant tuberculous axillary lymphadenitis that showed increased ¹⁸F-FDG uptake. A 39-year-old woman underwent preoperative ¹⁸F-FDG PET/computed tomography (CT) as a part of the work-up for right breast cancer. ¹⁸F-FDG PET/CT images showed a malignant lesion in the right breast with moderate ¹⁸F-FDG uptake, and multiple enlarged right axillary lymph nodes with intense ¹⁸F-FDG uptake. Subsequently, the patient underwent right mastectomy and right axillary lymph node dissection. Histopathological examination confirmed breast cancer and tuberculous lymphadenitis, and the patient was treated concomitantly with anti-tuberculous therapy.     

Incidentally Detected Enhancing Breast Lesions on Chest Computed Tomography

Objective

To evaluate the nature and imaging appearance of incidental enhancing breast lesions detected on a routine contrast-enhanced chest CT.

Materials and Methods

Twenty-three patients with incidental enhancing breast lesions on contrast-enhanced chest CT were retrospectively reviewed. The breast lesions were reviewed by unenhanced and enhanced CT, and evaluated by observing the shapes, margins, enhancement patterns and backgrounds of breast lesions. A histopathologic diagnosis or long-term follow-up served as reference standard.

Results

Sixteen (70%) patients had malignant breast lesions and seven (30%) had benign lesions. In 10 patients, the breast lesions were exclusively detected on contrast-enhanced CT. Using unenhanced CT, breast lesions with fibroglandular backgrounds were prone to be obscured (p < 0.001). Incidental primary breast cancer showed an non-significant trend of a higher percentage irregular margin (p = 0.056). All of the four incidental breast lesions with non-mass-like enhancement were proven to be malignant.

Conclusion

Routine contrast-enhanced chest CT can reveal sufficient details to allow for the detection of unsuspected breast lesions, in which some cases may be proven as malignant. An irregular margin of incidental enhancing breast lesion can be considered a suggestive sign of malignancy.     

Colorectal Cancer Outcomes in a Large Negative Computed Tomography Colonography Screening Cohort

IntroductionAt our institution, the most common cohort of individuals having computed tomography colonography (CTC) are those that require primary screening for colorectal cancer and were unable to tolerate or failed optical colonoscopy (OC). CTC is an efficient method for detecting polyps, masses, flat-lesions, and overt colorectal cancer, serving as a viable alternative to colonoscopy. This study follows patients with negative CTC results to evaluate the number of clinically significant lesions that may have been potentially missed by CTC. We suspect this number will be exceedingly low given the high sensitivity of this technique.MethodsAll patients with negative CTC screening (n = 509) in the Eastern Health Medical Health Region, located in Newfoundland and Labrador, Canada were included. An electronic medical record review was undertaken, encompassing provider, colonoscopy, imaging, and histopathology reports. Subjects were also checked through the Newfoundland Cancer Clinic Registry Database. All incidents of colorectal cancer were recorded.ResultsThe study cohort comprised 509 subjects. These subjects were followed for an average of 7.88 years. Two colorectal adenocarcinomas in this cohort were identified representing a crude cancer incidence rate of 0.49 cancers per 1000 patient years, and a rate of 0.39% following a normal CTC.ConclusionsColorectal cancer presenting clinically is rare in the 7.88 years following a negative CTC, suggesting CTC is equally effective for colorectal screening compared to OC. Furthermore, current guidelines that recommend interval CTC screening every 5 years is conservative, and interval screening can likely be recommended over a longer time frame.