Three-Dimensional Helical CT of the Breast: Accuracy for Measuring Extent of Breast Cancer Candidates for Breast Conserving Surgery

Objective. To evaluate the accuracy of three-dimensional (3D) helical computed tomography (CT) for assessing the extent of breast cancer of candidates for breast conserving surgery. Methods. Results of helical CT were studied in 144 lesions of 144 patients with breast cancer before breast-conserving surgery. A lesion was defined as positive if focal enhancement was detected by CT within 100s after contrast material administration. After resection, tumors were histopathologically mapped and correlated with the extent of 3D images. Results. Helical CT enabled detection of 143 tumors but not of one ductal carcinoma in situ (DCIS). The median deviation of the tumor extension revealed by 3D helical CT images from pathological assessment was 7.7mm (range 0–60mm). The extent of tumors was significantly correlated with CT measurements (r=0.714, p<0.0001). By multivariate analysis, the presence of invasive tumors with intraductal extensions beyond the edge of the invasive tumor and histologic type (DCIS) were significant risk factors for deviation of the tumor extension revealed by 3D helical CT images from pathological assessment. Conclusion. Three dimensional helical CT of the breast is an accurate preoperative imaging modality for assessing the extent of breast cancer candidates for breast conserving surgery.     

Computed tomography in miliary tuberculosis: Comparison with plain films,bronchoalveolar lavage,pulmonary functions and gas exchange

Computed tomography (CT) of the chest, pulmonary function tests, bronchoalveolar lavage (BAL) and arterial blood gas analysis were performed in 26 patients with non-HIV miliary tuberculosis (MTB). CT was repeated after treatment in 11 patients. Nodular lesions were characteristically seen on CT. CT showed discrete and fine nodules in five patients in whom the lesions appeared to be larger than miliary on chest X-rays. Coalescing nodular lesions were noted on chest X-rays (n= 7) and CT (n= 18). Consolidation (n= 6), cavitation (n= 4), fibrosis (n= 9) and air trapping (n= 14) were detected on CT only. During follow up, air trapping increased h = 14) and in some patients it appeared for the first time (n= 2). Lymph node enlargement and calcification were seen on both chest X-rays (n= 9 and (n= 3, respectively) and CT (n= 12 and n= 7, respectively). Pleural involvement was also seen in chest X-rays (n= 4) and CT (n= 5). Total lung capacity was higher in patients with a chest X-ray score > 10. Similarly a higher total cell count in BAL fluid was observed in patients with a CT score > 10. It is concluded from this study that CT is superior to chest X-rays in detecting nodular lesions, lymphadenopathy and air trapping in patients with MTB.     

大动脉CT血管成像的临床应用

为了评价CT血管成像对显示大动脉病变的作用,对疑为大动脉病变的28例病人(男20例,女8例,平均年龄为58岁)进行了CT血管成像检查,对兴趣区完成螺旋CT增强扫描后进行后处理;使用的血管成像方法有表面遮蔽重建、曲面多层重建和最大密度投影重建.检查后对6例进行了手术治疗,14例进行了常规血管造影和介入治疗.结果显示,除2例因扫描时相不适当使重建图像无诊断价值外,其余26例均清楚显示了兴趣区的大动脉解剖结构,包括大动脉瘤14例、大动脉夹层6例、大动脉创伤(假性动脉瘤)2例、大动脉穿透性溃疡1例、动脉硬化迂曲3例.上述结果表明,CT血管成像可清楚显示大动脉病变的解剖细节,对于选择治疗方法、观察治疗效果以及动态随访有重要价值.     

Usefulness of C-arm CT during superselective infusion chemotherapy for advanced head and neck carcinoma

Purpose of the study: To evaluate the usefulness of C‐arm computed tomography (CT) during superselective intra‐arterial infusion chemotherapy for advanced head and neck carcinoma. Methods: C‐arm CT was performed during superselective intra‐arterial infusion chemotherapy for 11 patients with advanced head and neck carcinoma located in the hypopharynx (n = 3), maxillary sinus (n = 3), oropharynx (n = 1), larynx (n = 1), extra‐auditory canal (n = 1), tonsil (n = 1) and tongue (n = 1). The usefulness of C‐arm CT during superselective catheterisation was evaluated. Results: On arteriography, nine tumours showed tumour stains and two in the oropharynx or tonsil showed no obvious tumour stains. C‐arm CT was performed one to four times (mean ± standard deviation, 2.5 ± 0.8) in each patient during a single procedure. C‐arm CT clearly showed not only the vascular territory of the selected branch but also the tumour itself in all patients. Intra‐arterial infusion chemotherapy was performed through one to three branches (mean, 1.7 ± 0.9) according to C‐arm CT findings without any complications. Conclusion: C‐arm CT during superselective intra‐arterial infusion chemotherapy was useful to determine the arterial supply of head and neck carcinoma. C‐arm CT may replace conventional CT during superselective arteriography in this procedure.     

Long‐term regional control in the observed neck following definitive chemoradiation for node‐positive oropharyngeal squamous cell cancer

Traditionally, patients treated with chemoradiotherapy for node‐positive oropharyngeal squamous cell carcinoma (N⁺ OPSCC) have undergone a planned neck dissection (ND) after treatment. Recently, negative post‐treatment positron‐emission tomography (PET)/computed tomography (CT) imaging has been found to have a high negative predictive value for the presence of residual disease in the neck. Here, we present the first comprehensive analysis of a large, uniform cohort of N⁺ OPSCC patients achieving a PET/CT‐based complete response (CR) after chemoradiotherapy, and undergoing observation, rather than ND. From 2002 to 2009, 302 patients with N⁺ OPSCC treated with 70 Gy intensity‐modulated radiation therapy and concurrent chemotherapy underwent post‐treatment clinical assessment including PET/CT. CR was defined as no evidence of disease on clinical examination and post‐treatment PET/CT. ND was reserved for patients with <CR on either PET/CT, clinical examination, or other imaging. 260 patients (86.1%) had clinical and radiographic CRs, and underwent neck observation (rate of regional control, 97.7%; 5‐year overall survival, 79.8%). The four observed patients experiencing neck recurrence had initial staging of N1 (n = 2), N2b (n = 1), and N2c (n = 1). Three of four were successfully surgically salvaged. There was no association between N stage and rate of neck recurrence (p = 0.74). 52 and 25% of patients undergoing ND had viable tumor in the neck after positive and negative PET/CT, respectively. We conclude that patients achieving CRs after chemoradiation, based on clinical and PET/CT assessment, have a high probability of regional control, with a 2.3% regional failure rate, and may be safely observed without planned ND.     

Intramural aortic dissection

We present 10 cases of intramural aortic dissection. The cases are all characterized by the presence of intramural haematoma without the presence of a patent false lumen. The radiological features and possible aetiologies are discussed. The key radiological finding is the presence of a hyperdense rim in the aortic wall on a non-contrast-enhanced computed tomography (CT) scan. In one case, a delayed diagnosis was made using magnetic resonance imaging (MRI). In a further case, the delayed development of a large aortic ulcer was demonstrated. Intramural aortic dissection has only recently been described in the radiological literature. The aetiology of this condition remains controversial. The imaging findings may be subtle and the diagnosis is still frequently being overlooked. We believe CT to be the primary diagnostic test for this condition, and its advantages over MRI and transoesophageal echocardiography (TOE) are discussed.     

Laparoscopic extraperitoneal para-aortic lymphadenectomy in locally advanced cervical cancer: a prospective correlation of surgical findings with positron emission tomography/computed tomography findings

BACKGROUND:

Failure to detect metastasis to para‐aortic nodes in patients with locally advanced cervical cancer leads to suboptimal treatment. No previous studies have prospectively compared positron emission tomography (PET)/computed tomography (CT) with laparoscopic extraperitoneal staging in the evaluation of para‐aortic lymph nodes.

METHODS:

Sixty‐five patients were enrolled; 60 were available for analysis. Patients with stage IB2‐IVA cervical cancer without evidence of para‐aortic lymphadenopathy on preoperative CT or magnetic resonance imaging (MRI) were prospectively enrolled. All patients underwent preoperative PET/CT. Laparoscopic extraperitoneal lymphadenectomy was performed from the common iliac vessels to the left renal vein.

RESULTS:

The median age at diagnosis was 48 years (range, 23‐84). The median operative time was 140 minutes (range, 89‐252). The median blood loss was 22.5 mL (range, 5‐150). The median length of hospital stay was 1 day (range, 0‐4). The median number of lymph nodes retrieved was 11 (range, 1‐39). Fourteen (23%) patients had histopathologically positive para‐aortic nodes. Of the 26 patients with negative pelvic and para‐aortic nodes on PET/CT, 3 (12%) had histopathologically positive para‐aortic nodes. Of the 27 patients with positive pelvic but negative para‐aortic nodes on PET/CT, 6 (22%) had histopathologically positive para‐aortic nodes. The sensitivity and specificity of PET/CT in detecting positive para‐aortic nodes when nodes were negative on CT or MRI were 36% and 96%, respectively. Eleven (18.3%) patients had a treatment modification based on surgical findings.

CONCLUSIONS:

Laparoscopic extraperitoneal para‐aortic lymphadenectomy is safe and feasible. Surgical staging of patients with locally advanced cervical cancer should be considered before planned radiation and chemotherapy. Cancer 2011. © 2010 American Cancer Society.     

Usefulness of 320-Row Area Detector Computed Tomography for the Diagnosis of Cystic Falx Meningioma

We present a case of cystic falx meningioma. Cystic meningioma is rare and not easy to diagnose preoperatively; it is often misdiagnosed as other tumors, including glial or metastatic tumors with cystic or necrotic changes. This study showed the potential impact of 320-row computed tomography (CT) on image-based diagnostic evaluation of cystic meningioma with special attention to the novel techniques of 4-dimensional CT angiography (4D-CTA) and CT whole-brain perfusion (CTP). 4D-CTA showed the arterial supply feeding the tumor and late enhancement of the tumor nodule, similar to that seen in meningioma by conventional angiography. CTP showed that the tumor had a higher cerebral blood flow and cerebral blood volume and a longer mean transit time than adjacent brain tissue. These findings were consistent with meningioma and reinforced the other imaging findings, resulting in the correct preoperative diagnosis. The new techniques available for 320-row CT can potentially be used to improve differential diagnosis and preoperative assessment of cystic tumors with nodules.Key words: Cystic meningioma, 320-row area detector computed tomography, 4-dimensional computed tomography angiography, Computed tomography perfusion     

Comparative study of the value of dual tracer PET/CT in evaluating breast cancer

The present study was conducted to assess the relationship between tumor uptake and pathologic findings using dual‐tracer PET/computed tomography (CT) in patients with breast cancer. Seventy‐four patients with breast cancer (mean age 54 years) who underwent ¹¹C‐choline and 2‐[¹⁸F]fluoro‐2‐deoxy‐d ‐glucose (¹⁸F‐FDG) PET/CT prior to surgery on the same day were enrolled in the present study. Images were reviewed by a board‐certified radiologist and two nuclear medicine specialists who were unaware of any clinical information and a consensus was reached. Uptake patterns and measurements of dual tracers were compared with the pathologic findings of resected specimens as the reference standard. Mean (±SD) tumor size was 5.9 ± 3.2 cm. All primary tumors were identified on ¹⁸F‐FDG PET/CT and ¹¹C‐choline PET/CT. However, ¹⁸F‐FDG PET/CT demonstrated focal uptake of the primary tumor with (n = 38; 51%) or without (n = 36; 49%) diffuse background breast uptake. Of the pathologic findings, multiple logistic regression analysis revealed an independent association between fibrocystic change and diffuse background breast uptake (odds ratio [OR] 8.57; 95% confidence interval [CI] 2.86–25.66; P < 0.0001). Tumors with higher histologic grade, nuclear grade, structural grade, nuclear atypia, and mitosis had significantly higher maximum standardized uptake values (SUV_max) and tumor‐to‐background ratios (TBR) for both tracers. Multiple logistic regression analysis revealed that only the degree of mitosis was independently associated with a high SUV_max (OR 7.45; 95%CI 2.21–25.11; P = 0.001) and a high TBR (OR 5.41; 95%CI 1.13–25.96; P = 0.035) of ¹¹C‐choline PET/CT. In conclusion, ¹¹C‐choline may improve tumor delineation and reflect tumor aggressiveness on PET/CT in patients with breast cancer.     

Patient with Leriche's syndrome and concomitant superior mesenteric aneurysm: Evaluation with contrast‐enhanced three‐dimensional magnetic resonance angiography,computed tomography angiography and digital subtraction angiography

Conventional angiography is regarded as the gold standard in vascular imaging but it is invasive, and difficulty may be encountered in the evaluation of aortic occlusion disease. Superior mesenteric artery aneurysm is an uncommon disease, which can result in life‐threatening haemorrhage after rupture. With the rapid development of computed tomography angiography (CTA) and magnetic resonance angiography (MRA), high‐quality images of the vascular system can be obtained in a non‐invasive manner. We report a case of Leriche's syndrome with concomitant superior mesenteric aneurysm using contrast‐enhanced 3‐D CTA and MRA, with digital subtraction angiography correlation.     

Magnetic Resonance Imaging of Aortic Aneurysms with 3-D Image Reconstruction

A programme was written to detect flow in a sequence of MR images and to construct 3-D vessel maps from the detected flow regions. Reduction in first echo intensity and prolongation of calculated T2 value were used as flow-detection criteria. The programme was used to image the aorta in 6 patients with abdominal aortic aneurysm and 5 patients with aortic dissection. Results were compared with contrast angiography in 9 cases and X-ray CT in 2. The images obtained by the two techniques were comparable in 9 cases. In 2 cases of aortic dissection, where flow in the false lumen was slow, the false lumen could not be demonstrated by angiography, but was clearly seen in the reconstructed MR images.     

MSCTA在脑血管性疾病诊断中的应用价值

Objective： To evaluate the clinical value of multi-slice helical CT angiography （MSCTA） in diagnosis of cerebral vascular diseases. Methods： 52 patients with cerebral vascular diseases were examined with GE Light Speed 4-slice and 16-slice helical CT. Pitch： 0.5-3, slice thickness： 0.625-1.25 mm, adult injection dosage： 90-100 mL, children injection dosage： 2 mL/kg, injection rate： 2.5-4.0 mL/s, delay time： 15-22 s. Intelligent track scan （Smart prep Rx） were adopted in parts of these cases. Three-dimensional cerebral vascular images were processed at ADW 3.1 and ADW 4.2 workstation. Results： MSCTA could clearly display spacious anatomic details of cerebral aneurysm, including its origin, size, neck width, and trend etc. MSCTA results of 19 cases were consistent with those of operations. The diameter of the smallest cerebral aneurysm shown in our research was about 3 mm. As a non-invasive examination, MSCTA could also be applied in post-operational evaluation of cerebral aneurysm by observing the location of silver clip and the distant vessels. Besides, MSCTA could be used to diagnose arteriovenous malformation and moyamoya disease. Of all the three-dimentional imaging methods, volume rendering （VR） is the best means to display the cerebral vascular diseases. Conclusion： As a non-invasive examination, MSCTA plays an important role in detection, pre-operational and post-operational evaluation of cerebral vascular diseases.     

Non‐small cell lung cancer brain metastasis screening in the era of positron emission tomography‐CT staging: Current practice and outcomes

Introduction

Several clinical guidelines indicate that brain metastasis screening (BMS) should be guided by disease stage in non‐small cell lung cancer (NSCLC). We estimate that screening is performed more broadly in practice, and patients undergo brain imaging at considerable cost with questionable benefit. Our aim was to quantify the use and detection rate of BMS in a contemporary cohort staged with ¹⁸F‐fluorodeoxyglucose positron emission tomography/computed tomography (PET‐CT).

Methods

We conducted a retrospective review of prospectively collected data from three major lung cancer referral centres in Brisbane between January 2011 and December 2015. Patients included had a new diagnosis of NSCLC and had undergone a PET‐CT to stage extra‐cranial disease. BMS was defined as dedicated brain imaging with contrast‐enhanced computed tomography (CE‐CT) or magnetic resonance (MR), in the absence of clinically apparent neurological deficits.

Results

A total of 1751 eligible cases were identified and of these 718 (41%) underwent BMS. The majority had CE‐CT imaging (n = 703). Asymptomatic brain metastases (BM) were detected in 18 patients (2.5%). Of these patients, 12 had concurrent non‐brain metastases. Only six patients (0.8%) had BM alone. The rate of detection increased with N‐stage (P = 0.02) and overall stage (P < 0.001). It was 0.5%, 1%, 1.6% and 7.3% for stage I, II, III and IV respectively. The overall screening rate increased with T‐stage (P = 0.001), N‐Stage (P < 0.001) and overall stage (P < 0.001).

Conclusions

Non‐small cell lung cancer BMS practices remain at odds with published guidelines. The low number of occult BMs detected supports the existing international recommendations. Rationalising BMS would minimise the burden on patients and the health care system.     

Perimesencephalic subarachnoid haemorrhage: Negative angiography and favourable prognosis

The computed tomography (CT) scans of 110 consecutive patients who presented, over a 4.5-year period, following spontaneous subarachnoid haemorrhage (SAH), were reviewed. All 110 patients also had one or more 4-vessel digital subtraction cerebral angiograms. The CT scans were reviewed in each case without knowledge of the angiographic result. In nine patients (8%), SAH was confined to the perimesencephalic area, interpeduncular cistern and/or prepontine region at CT. All nine patients had at least two, and some as many as four, negative cerebral angiograms. Eighteen of the 110 patients (16%) ultimately had negative angiography. Hence, the patients with isolated perimesencephalic haemorrhage (PMH) accounted for 50% of the negative angiograms. There was a significant association between isolated PMH and negative angiography (X²= 50.1, P < 0.005). The specificity of PMH for negative angiography was 100% (95% confidence interval (CI) = 97–100%) and the sensitivity of PMH for a negative study was 50% (95% CI = 16–84%). Six of the 110 patients had basilar artery aneurysms demonstrated angiographically as the cause of their SAH but none of these six had isolated PMH at CT. All patients with isolated PMH were alive and well at follow up and none had suffered repeat SAH or vasospasm-related ischaemic cerebral injury. Perimesencephalic haemorrhage should be distinguished from SAH in general, because of the good prognosis associated with it and the doubtful need for repeat cerebral angiography after an intitial negative study.     

MR Imaging of Abdominal Aortic Aneurysm

Eight patients with abdominal aortic aneurysms were evaluated with magnetic resonance imaging (MRI). The MRI findings were verified by surgery in five, compared with ultrasonography in eight, with computed tomography in four and with angiography in eight patients. The size and extent of aneurysm, presence of thrombus, size of the residual lumen and involvement of branch vessels were readily demonstrated by MRI. Whilst sonography should remain the screening procedure of choice in patients with suspected abdominal aortic aneurysms, this early experience suggests that MRI may prove to be a noninvasive and adequate means of evaluating patients prior to surgery.     

Roles of ultrasonography and computed tomography in the surgical management of cervical lymph node metastases in papillary thyroid carcinoma

Aims

Adequate evaluation and surgical management of cervical lymph node metastasis is very important in papillary thyroid carcinoma (PTC). The aim of this study was to evaluate the impact of preoperative ultrasonography (US) and computed tomography (CT) on the surgical management of cervical lymph node metastases in PTC.

Methods

Medical records and imaging findings were retrospectively analyzed for 252 patients with PTC who underwent thyroidectomy with neck dissection.

Results

The sensitivity of both imaging techniques was lower in the central neck (US 23%, CT 41%) than in the lateral neck (US 70%, CT 82%). The specificities of US and CT were 97% and 90% in the central neck, and 84% and 64% in the lateral neck, respectively. Our surgical plans for therapeutic neck dissection were based on imaging findings in 59% of patients who underwent lateral compartment neck dissection and in 32.1% of patients who underwent central compartment neck dissection, respectively.

Conclusions

The roles of preoperative US and CT in surgical planning for central compartment neck dissection in PTC are limited because of their low sensitivity in the central neck, but US and CT may be useful in cases with non-palpable lateral neck nodes.     

Positron emission tomography (PET) for assessment of axillary lymph node status in early breast cancer: A systematic review and meta-analysis

Purpose

Sentinel lymph node biopsy (SLNB) and axillary lymph node dissection (ALND) are used to assess axillary nodal status in breast cancer, but are invasive procedures associated with morbidity, including lymphoedema. This systematic review evaluates the diagnostic accuracy of positron emission tomography (PET), with or without computed tomography (CT), for assessment of axillary nodes in early breast cancer.

Methods

Eleven databases including MEDLINE, EMBASE and the Cochrane Library, plus research registers and conference proceedings, were searched in April 2009. Study quality was assessed using the QUality Assessment of Diagnostic Accuracy Studies (QUADAS) checklist. Sensitivity and specificity were meta-analysed using a bivariate random effects approach.

Results

Across 26 studies evaluating PET or PET/CT (n = 2591 patients), mean sensitivity was 63% (95% CI: 52-74%; range 20-100%) and mean specificity 94% (95% CI: 91-96%; range 75-100%). Across 7 studies of PET/CT (n = 862), mean sensitivity was 56% (95% CI: 44-67%) and mean specificity 96% (90-99%). Across 19 studies of PET-only (n = 1729), mean sensitivity was 66% (50-79%) and mean specificity 93% (89-96%). Mean sensitivity was 11% (5-22%) for micrometastases (≤2 mm; five studies; n = 63), and 57% (47-66%) for macrometastases (>2 mm; four studies; n = 111).

Conclusions

PET had lower sensitivity and specificity than SLNB. Therefore, replacing SLNB with PET would avoid the adverse effects of SLNB, but lead to more false negative patients at risk of recurrence and more false positive patients undergoing unnecessary ALND. The present evidence does not support the routine use of PET or PET-CT for the assessment of the clinically negative axilla.     

Correlation between fluorodeoxyglucose hotspots on preradiotherapy PET/CT and areas of cancer local relapse: Systematic review of literature

The aim of the present paper is to systematically review all available literature on preradiotherapy high uptake areas (hotspots) as a potential target for dose escalation in different tumour sites, and to understand the potential role and limitations of fluorodeoxyglucose (FDG)-positron-emission tomography (PET)/computed tomography (CT) in this context. An electronic database (Medline) search was conducted to identify articles reporting on a correlation between high tracer uptake on pretreatment PET and preferential sites of local recurrence after radiotherapy. Search was limited to English language. No date range limitation was applied. Among 45 studies initially identified, nine series matching with inclusion criteria have finally been retained from the literature after reviewing (5 retrospective and 4 prospective). Primary tumour locations were head-neck (n = 2), lung (n = 4), oesophageal (n = 2) and rectal (n = 1) areas. Overlaps between FDG hotspot on preradiotherapy PET/CT and site of local recurrence on post-treatment scan showed good to excellent agreement. Only studies on head-neck cancer reported moderate agreement probably explained by the lack of reproducibility of the patients positioning between pre- and post-treatment FDG-PET/CT; and by the rigid registration process of images limited by post-therapeutic changes that highly affect anatomical landmarks. FDG hotspot-guided radiotherapy may allow dose escalation in respecting a robust methodology (treatment position, co-registration method, four-dimensional PET).     

Prevalence of non 18F‐fluorodeoxyglucose‐avid incidental findings of clinical significance on whole body positron emission tomography/computed tomography: A review of 500 consecutive cases

Introduction

The prevalence of incidental ¹⁸F‐fluorodeoxyglucose (FDG)‐avid findings on positron emission tomography–computed tomography (PET/CT) has been extensively described. Few studies, however, have assessed the prevalence and significance of non‐FDG‐avid findings; pathology that is identified on review of the low‐dose, non‐contrast CT. The aim of this study was to determine the overall prevalence of non FDG‐avid incidental findings on PET/CT and the prevalence of ‘clinically significant’ non FDG‐avid pathology.

Methods

Five hundred consecutive whole body PET/CT studies performed in 2016 at a university affiliated tertiary hospital were retrospectively reviewed by two radiologists experienced in reporting PET/CT. Findings were categorized according to potential clinical relevance, and a targeted follow‐up of clinically significant incidental findings was performed.

Results

Incidental findings were encountered in 463 of 500 (92.6%) patients. In 226 patients, these findings had been detected on previous imaging studies, with unknown incidental findings present in 237 of 500 (47.4%) patients. 113 of 500 (22.6%) patients had non‐avid incidental findings of potentially major clinical significance, and in 35 patients (7.0%) these findings were considered previously unknown. The most common non‐avid findings of potentially major significance were pulmonary nodules (6 mm or larger), moderate or large size pleural effusions, and vascular aneurysms. Unknown incidental findings of potentially major clinical significance were significantly higher in patients imaged for melanoma staging (P= 0.004).

Conclusion

The prevalence of incidental findings of clinical significance that do not accumulate FDG in PET/CT is not insignificant. Routine systematic review of the low‐dose CT is required to avoid missing potentially clinically important findings, in particular pleural effusions, vascular aneurysms and metastatic pulmonary nodules.     

How useful is preoperative imaging for tumor,node, metastasis (TNM) staging of gastric cancer? A meta-analysis

Background

Surgery is the fundamental curative option for gastric cancer patients. Imaging scans are routinely prescribed in an attempt to stage the disease prior to surgery. Consequently, the correlation between radiology exams and pathology is crucial for appropriate treatment planning.

Methods

Systematic searches were conducted using Medline, Embase, and the Cochrane Central Register of Controlled Trials from January 1, 1998 to December 1, 2009. We calculated the accuracy, overstaging rate, understaging rate, Kappa statistic, sensitivity, and specificity for abdominal ultrasound (AUS), computed tomography (CT), magnetic resonance imaging (MRI), and positron emission tomography (PET) with respect to the gold standard (pathology). We also compared the performance of CT by detector number and image type. A meta-analysis was performed.

Results

For pre-operative T staging MRI scans had better performance accuracy than CT and AUS; CT scanners using ≥4 detectors and multi-planar reformatted (MPR) images had higher staging performances than scanners with <4 detectors and axial images only. For pre-operative N staging PET had the lowest sensitivity, but the highest specificity among modalities; CT performance did not significantly differ by detector number or addition of MPR images. For pre-operative M staging performance did not significantly differ by modality, detector number, or MPR images.

Conclusions

The agreement between pre-operative TNM staging by imaging scans and post-operative staging by pathology is not perfect and may affect treatment decisions. Operator dependence and heterogeneity of data may account for the variations in staging performance. Physicians should consider this discrepancy when creating their treatment plans.