How Reliable Is CT Scan in Staging Right Colon Cancer?

BACKGROUND: The observation of inferior oncologic outcomes after surgery for proximal colon cancers has led to the investigation of alternative treatment strategies, including surgical procedures and neoadjuvant systemic chemotherapy in selected patients. OBJECTIVE: The purpose of this study was to determine the accuracy of CT staging in proximal colon cancer in detecting unfavorable pathologic features that may aid in the selection of ideal candidates alternative treatment strategies, including extended lymph node dissection and/or neoadjuvant chemotherapy. DESIGN: This was a retrospective consecutive series. SETTINGS: Trained abdominal radiologists from 2 centers performed a blinded review of CT scans obtained to locally stage proximal colon cancer according to previously defined prognostic groups, including T1/2, T3/4, N+, and extramural venous invasion. CT findings were compared with histopathologic results as a reference standard. Unfavorable pathologic findings included pT3/4, pN+, or extramural venous invasion. PATIENTS: Consecutive patients undergoing right colectomy in 2 institutions between 2011 and 2016 were retrospectively reviewed from a prospectively collected database. MAIN OUTCOME MEASURES: T status, nodal status, and extramural venous invasion status comparing CT with final histologic findings were measured. RESULTS: Of 150 CT scans reviewed, CT failed to identify primary cancer in 18%. Overall accuracy of CT to identify unfavorable pathologic features was 63% with sensitivity, specificity, positive predictive value, and negative predictive value of 63% (95% CI, 54%-71%), 63% (95% CI, 46%-81%), 87% (95% CI, 80%-94%) and 30% (95% CI, 18%-41%). Only cT3/4 (55% vs 45%; p = 0.001) and cN+ (42% vs 58%; p = 0.02) were significantly associated with correct identification of unfavorable features at final pathology. CT scans overstaged and understaged cT in 23.7% and 48.3% and cN in 28.7% and 53.0% of cases. LIMITATIONS: The study was limited by its retrospective design, relatively small sample size, and heterogeneity of CT images performed in different institutions with variable equipment and technical details. CONCLUSIONS: Accuracy of CT scan for identification of pT3/4, pN+, or extramural venous invasion was insufficient to allow for proper identification of patients at high risk for local recurrence and/or in whom to consider alternative treatment strategies. Locoregional overstaging and understaging resulted in inappropriate treatment strategies in <48%. See Video Abstract at http://links.lww.com/DCR/A935.

Optimizing radiologist e-prescribing of CT oral contrast agent using a protocoling portal.

OBJECTIVE: The purpose of this study is to quantify the time expenditure associated with radiologist ordering of CT oral contrast media when using an integrated protocoling portal and to determine radiologists' perceptions of the ordering process. SUBJECTS AND METHODS: This prospective study was performed at a large academic tertiary care facility. Detailed timing information for CT inpatient oral contrast orders placed via the computerized physician order entry (CPOE) system was gathered over a 14-day period. Analyses evaluated the amount of physician time required for each component of the ordering process. Radiologists' perceptions of the ordering process were assessed by survey. Descriptive statistics and chi-square analysis were performed. RESULTS: A total of 96 oral contrast agent orders were placed by 13 radiologists during the study period. The average time necessary to create a protocol for each case was 40.4 seconds (average range by subject, 20.0-130.0 seconds; SD, 37.1 seconds), and the average total time to create and sign each contrast agent order was 27.2 seconds (range, 10.0-50.0 seconds; SD, 22.4 seconds). Overall, 52.5% (21/40) of survey respondents indicated that radiologist entry of oral contrast agent orders improved patient safety. A minority of respondents (15% [6/40]) indicated that contrast agent order entry was either very or extremely disruptive to workflow. CONCLUSION: Radiologist e-prescribing of CT oral contrast agents using CPOE can be embedded in a protocol workflow. Integration of health IT tools can help to optimize user acceptance and adoption.

Renal cell carcinoma containing abundant non-calcified fat.

Renal masses found to contain macroscopic fatty elements on CT or MRI imaging can generally be classified as benign angiomyolipomas. Rarely, renal cell carcinomas may also contain evidence of macroscopic fat. When true adipocytic elements are present, this is generally due to a process of osseous metaplasia in which both fat cells and calcification are co-localized within the mass. We present a patient with a large papillary renal cell carcinoma containing abundant fat with sparse, punctate calcification remote from the fatty elements on imaging. This report highlights the need for radiologists to maintain caution when diagnosing renal angiomyolipomas on the basis of macroscopic fat and reviews the current literature on fat-containing renal masses.

Exposing exposure: enhancing patient safety through automated data mining of nuclear medicine reports for quality assurance and organ dose monitoring.

PURPOSE: To develop and validate an open-source informatics toolkit capable of creating a radiation exposure data repository from existing nuclear medicine report archives and to demonstrate potential applications of such data for quality assurance and longitudinal patient-specific radiation dose monitoring. MATERIALS AND METHODS: This study was institutional review board approved and HIPAA compliant. Informed consent was waived. An open-source toolkit designed to automate the extraction of data on radiopharmaceuticals and administered activities from nuclear medicine reports was developed. After iterative code training, manual validation was performed on 2359 nuclear medicine reports randomly selected from September 17, 1985, to February 28, 2011. Recall (sensitivity) and precision (positive predictive value) were calculated with 95% binomial confidence intervals. From the resultant institutional data repository, examples of usage in quality assurance efforts and patient-specific longitudinal radiation dose monitoring obtained by calculating organ doses from the administered activity and radiopharmaceutical of each examination were provided. RESULTS: Validation statistics yielded a combined recall of 97.6% ± 0.7 (95% confidence interval) and precision of 98.7% ± 0.5. Histograms of administered activity for fluorine 18 fluorodeoxyglucose and iodine 131 sodium iodide were generated. An organ dose heatmap which displays a sample patient's dose accumulation from multiple nuclear medicine examinations was created. CONCLUSION: Large-scale repositories of radiation exposure data can be extracted from institutional nuclear medicine report archives with high recall and precision. Such repositories enable new approaches in radiation exposure patient safety initiatives and patient-specific radiation dose monitoring.

Primary non-small cell lung cancer: review of frequency, location, and time of recurrence after radiofrequency ablation.

PURPOSE: To review the recurrence patterns in patients with primary non-small cell lung cancer (NSCLC) treated with percutaneous image-guided radiofrequency (RF) ablation. MATERIALS AND METHODS: This retrospective review was institutional review board approved and HIPAA compliant. Informed consent was waived. Data from all patients with primary NSCLC who underwent lung RF ablation from January 1998 to January 2008 were reviewed. Ninety-one patients were identified. Ten patients with no posttreatment imaging results and two patients with multiple treated lung cancers were excluded. There were 79 tumors in 79 patients (mean age, 75 years). Mean tumor size was 2.5 cm (range, 1-5.5 cm). Fifteen (19%) tumors were central, and 64 (81%) tumors were peripheral. Nineteen (24%) patients underwent adjuvant external beam radiation, and nine (11%) patients underwent concomitant brachytherapy. Correlation of computed tomography and positron emission tomography imaging studies with biopsy results, tumor size, location, and stage was performed. Patterns of recurrence were classified as local, intrapulmonary, nodal, mixed (local and nodal), and distant. RESULTS: Forty-five (57%) patients demonstrated no evidence of recurrence at follow-up imaging (range, 1-72 months; mean, 17 months). Recurrence was seen in 34 (43%) patients (range, 2-48 months; mean, 14 months). Recurrence after RF ablation was local in 13 (38%), intrapulmonary in six (18%), nodal in six (18%), mixed in two (6%), and distant metastases in seven (21%) cases. Median disease-free survival was 23 months. Sex, tumor location, and radiation therapy were not associated with risk of recurrence. Increasing tumor size (P = .02) and stage (P = .007) were related to risk of recurrence. CONCLUSION: The most common pattern of recurrence was local, which suggests that more aggressive initial RF ablation and adjuvant radiation may offer improvement in outcomes. Continued follow-up imaging is needed because new recurrences were seen throughout the 2 years following treatment.

Radiofrequency and microwave tumor ablation in patients with implanted cardiac devices: is it safe?

PURPOSE: To identify malfunction of implanted cardiac devices during or after thermal ablation of tumors in lung, kidney, liver or bone, using radiofrequency (RF) or microwave (MW) energy. MATERIALS AND METHODS: After providing written consent, 19 patients (15 men and 4 women; mean age 78 years) with pacemakers or pacemaker/defibrillators underwent 22 CT image-guided percutaneous RF or MW ablation of a variety of tumors. Before and after each procedure, cardiac devices were interrogated and reprogrammed by a trained cardiac electrophysiology fellow. Possible pacer malfunctions included abnormalities on electrocardiographic (EKG) monitoring and alterations in device settings. Our institutional review board approved this Health Insurance Portability and Accountability Act-compliant study. Informed consent for participation in this retrospective study was deemed unnecessary by our review board. RESULTS: During 20 of 22 sessions, no abnormalities were identified in continuous, EKG tracings or pacemaker functions. However, in two sessions significant changes, occurred in pacemaker parameters: inhibition of pacing during RF application in one, session and resetting of mode by RF energy in another session. These changes did not, result in hemodynamic instability of either patient. MW ablation was not associated with, any malfunction. In all 22 sessions, pacemakers were undamaged and successfully reset to original parameters. CONCLUSION: RF or MW ablation of tumors in liver, kidney, bone and lung can be performed safely in patients with permanent intra-cardiac devices, but careful planning between radiology and cardiology is essential to avoid adverse outcomes.

Microwave ablation in the treatment of primary lung tumors.

Recent years have witnessed the refinement and significant growth of several new, minimally invasive approaches for the nonsurgical treatment of primary lung malignancies. For select patients, these technologies offer an attractive treatment option given their availability in the outpatient setting and low associated morbidity and mortality. Microwave ablation represents the most recent addition to the growing armamentarium of available ablative technologies. Administered in a manner similar to radiofrequency ablation, the lung tumor is localized under imaging guidance, and a microwave antenna is placed directly into the tumor bed. In contrast to existing thermoablative technologies, however, microwave treatment offers several key theoretical advantages. These include consistently higher intratumoral temperatures, larger ablation volumes, reduced treatment times, and improved convection profile. As a nascent technology, efficacy and outcomes data for microwave ablation of pulmonary malignancies remain relatively lacking compared with other thermoablative techniques; however, early trials have demonstrated promising results. It is hoped that further refinements in the clinical application of this technology will continue to improve the care of patients with lung cancer.