Iodinated Contrast Enhancement of Breast Cancer on Prone Multidetector Computed Tomography-Preliminary Findings.

OBJECTIVES: Contrast-enhanced breast imaging has gained increasing importance in the diagnosis and management of breast cancer. The aim of this study was to assess breast cancer enhancement after contrast administration on prone multidetector computed tomography (MDCT). MATERIALS AND METHODS: This retrospective, unicentric, institutional review board-approved study included patients with newly diagnosed breast cancer who were submitted to contrast-enhanced MDCT in prone position, with image acquisition before and after nonionic iodinated contrast administration. RESULTS: Sixty breast cancer patients aged between 31 and 74 years (mean, 49 years) were included. Most patients (n = 50, 83.3%) had no special type invasive breast carcinoma and luminal subtype (n = 45, 75%). All index breast tumors were identified on prone MDCT. Forty-three cases (70.5%) presented as mass, 13 (21.3%) as nonmass enhancement and 4 (6.6%) as both mass and nonmass enhancement. Mean tumor density was 37.8 HU and 87.9 HU on precontrast and postcontrast images, respectively. Mean contrast enhancement was 50.2 HU (range, 20-109 HU). There were no statistically significant differences in tumor enhancement according to histological type, molecular subtype, nuclear grade, tumor size, or imaging presentation. CONCLUSIONS: Our results show that breast cancer usually can be identified and have significant contrast enhancement on prone MDCT images. This method could be used as an alternative when other contrast-enhanced breast imaging methods are not available.

Functional and metabolic imaging in transthoracic biopsies guided by computed tomography.

OBJECTIVES: CT-guided biopsy of indeterminate lung lesions sometimes provides insufficient histological results due to tumor necrosis. Functional and metabolic methods such as DWI-MR and PET-CT may help by directing sample collection to a lesion area of greater biological representativeness. The objective is to evaluate the histopathological results based on findings on ADC and SUV levels in lung lesions suspected for primary cancer. METHODS: Tissue samples were evaluated after undergoing biopsies guided by either DWI-MR or PET-CT findings. In each patient, sample collection from two lesion areas was guided by local ADC and SUV. Values were used to define areas of low vs. high suspicion for cancer. RESULTS: Patients who underwent DWI-MR had median lesion size of 78.0 mm. Areas of higher suspicion (HSA) had a median ADC of 1.1 × 10-3 mm2/s, while areas of lower suspicion (LSA) had median ADC of 1.8 × 10-3 mm2/s (p = 0.0001). All HSA samples and 71.43% of LSA samples were positive for cancer (p = 0.0184). Patients who performed PET-CT had median lesion size of 61.0 mm. Median SUV was 7.1 for HSA and 3.9 for LSA (p = 0.0002). Positivity for cancer was observed in 76.9% of samples for both HSA and LSA (p = 0.0522). CONCLUSION: Use of DWI-MR and PET-CT showed that tumors are functional and metabolically heterogeneous and that this heterogeneity has implications for histopathological diagnosis. KEY POINTS: • Lung cancer is heterogeneous regarding functional and metabolic imaging. • Tumor heterogeneity may have implications in histopathological diagnosis. • Intralesional lower levels of ADC target highly suspected areas with a significant improvement in lung cancer diagnosis.

JOURNAL CLUB: Preparative Fasting for Contrast-Enhanced CT in a Cancer Center: A New Approach.

OBJECTIVE: Most diagnostic imaging centers ask patients to fast for 4-6 hours before contrast-enhanced CT. Previous studies have shown that prolonged fasting can be harmful. In addition, manufacturers of contrast agents claim that there is no special preparation needed before examination. The aim of this study was to evaluate the effects of preparative fasting on contrast-enhanced CT at a cancer center. SUBJECTS AND METHODS: Outpatients (n = 3206) were prospectively evaluated and randomly assigned to two groups: the 1619 patients in group 1 fasted for at least 4 hours before the examination, whereas the 1587 patients in group 2 received a light meal. Adverse symptoms observed before and after contrast agent administration were compared between groups. RESULTS: Adverse symptoms occurring after IV contrast agent administration were reported by 45 patients (1.5%) in group 1 and 30 patients (0.9%) in group 2. The most common symptoms were nausea (n = 32), weakness (n = 12), and vomiting (n = 5). The frequency of symptoms did not differ statistically significantly between groups (p > 0.05). CONCLUSION: In this sample of patients with cancer undergoing contrast-enhanced CT, very few adverse symptoms were reported regardless of preparative fasting. These results support the idea that preparation for contrast-enhanced CT can be simplified, decreasing the discomfort and inconvenience experienced by patients.

Focused abdominal ultrasound in preoperative liver surgery staging: a prospective study.

BACKGROUND: Because of its safety, relative low cost and widespread availability, conventional ultrasound (US) is the modality of choice for initial evaluation of the liver. Following US, in patients eligible for surgery, further computed tomography and/or magnetic resonance imaging is usually recommended for surgical planning. There are no recent published series focusing on conventional abdominal US exclusively employed for the evaluation of liver nodules before surgery. The objective of this study is to evaluate the efficacy of focused conventional preoperative US in detecting liver lesions, and the impact of US findings on surgical management. METHODS: Sixty-seven noncirrhotic patients underwent surgical resection, after being previously submitted to focused liver US evaluation. US results were compared with intraoperative US (IOUS) and histology (gold standard). The IOUS was performed by the same radiologist who performed the preoperative US. Patient-by-patient and lesion-by-lesion analyses were performed. RESULTS: A total of 241 lesions were depicted in 67 patients. The mean number of lesions detected per patient by US and IOUS was 2.37 and 3.37, respectively (P = 0.001). In 52.2% of patients, US and IOUS depicted the same number of liver lesions. Surgery with curative intent was conducted in 61 (91.0%) patients. Histological evaluation was obtained in 196 lesions; 155 were considered malignant. The overall lesions detection rate by US was 65.6%. For lesions <15 mm and lesions ≥15 mm, US showed a sensitivity rate of 55.3% and 75.5%, respectively. CONCLUSIONS: The relatively high sensitivity rates achieved by US focused on liver evaluation, with the aim of lowering costs but not efficiency, places the method in focus again for use in the routine preoperative staging of candidates for liver resection. We suggest for preoperative evaluation that US could be associated with one section imaging method (computed tomography or magnetic resonance imaging) as routine.

Multidetector Computed Tomography with Dedicated Protocol for Breast Cancer Locoregional Staging: Feasibility Study.

BACKGROUND: The aim of this study was to demonstrate the feasibility of performing multidetector computed tomography (MDCT) with a dedicated protocol for locoregional staging in breast cancer patients. METHODS: This prospective single-center study included newly diagnosed breast cancer patients submitted to contrast-enhanced chest MDCT and breast magnetic resonance imaging (MRI). MDCT was performed in prone position and using subtraction techniques. Fleiss' Kappa coefficient (K) and intraclass correlation coefficient (ICC) were used to assess agreement between MRI, MDCT, and pathology, when available. RESULTS: Thirty-three patients were included (mean age: 47 years). Breast MRI and MDCT showed at least substantial agreement for evaluation of tumor extension (k = 0.674), presence of multifocality (k = 0.669), multicentricity (k = 0.857), nipple invasion (k = 1.000), skin invasion (k = 0.872), and suspicious level I axillary lymph nodes (k = 0.613). MDCT showed higher number of suspicious axillary lymph nodes than MRI, especially on levels II and III. Both methods had similar correlation with tumor size (MRI ICC: 0.807; p = 0.008 vs. MDCT ICC: 0.750; p = 0.020) and T staging (k = 0.699) on pathology. CONCLUSIONS: MDCT with dedicated breast protocol is feasible and showed substantial agreement with MRI features in stage II or III breast cancer patients. This method could potentially allow one-step locoregional and systemic staging, reducing costs and improving logistics for these patients.

A New CT-Guided Modified Trocar Technique for Drainage of Difficult Locations Abscesses.

PURPOSE: Computed tomography (CT) is commonly used to guide drainage of deep-seated abdominal fluid collections. However, in some cases, these collections seem to be inaccessible due to surrounding organs or their being in difficult locations. The aim of this study is to describe a modified Trocar technique to drain collections in difficult locations, especially those in the subphrenic space, without passing through intervening organs. MATERIALS AND METHODS: This retrospective case series study describes seven inpatients who underwent CT-guided drainage using a modified Trocar technique for abscesses that are difficult to access percutaneously. All patients provided written informed consent prior to the procedure. After placement of a 12-14F catheter inside the peritoneum, the Trocar stylet was removed so that the tip of the catheter became blunt and flexible to avoid injury to organs and structures in the catheter route, and the catheter was slowly advanced towards the collection using CT guidance and tactile sensation. After reaching the target, the stylet was reintroduced to enter the abscess wall. RESULTS: All procedures were performed using an anterior abdominal wall access with adequate catheter positioning and resulted in clinical status improvement in the days after the drainage. No complications related to the procedure were identified in any of the patients. CONCLUSIONS: The modified Trocar technique for percutaneous CT-guided drainage of abdominal abscesses may be feasible for lesions that are difficult to access with conventional methods.

Computed tomographically guided injection of cyanoacrylate in association with preoperative radioguided occult lesion localization of ground-glass opacities.

Intraoperative localization of a ground-glass opacity (GGO) is difficult because it is not easy to palpate and may be invisible at radioscopy. Therefore various techniques have been developed to improve intraoperative localization of these lesions, allowing adequate surgical resection. We report 2 cases of preoperative localization of GGOs through computed tomographically guided injection of cyanoacrylate in association with radioguided occult lesion localization (ROLL).

Computed tomography-guided percutaneous core needle biopsy in pancreatic tumor diagnosis.

AIM: To evaluate the techniques, results, and complications related to computed tomography (CT)-guided percutaneous core needle biopsies of solid pancreatic lesions. METHODS: CT-guided percutaneous biopsies of solid pancreatic lesions performed at a cancer reference center between January 2012 and September 2013 were retrospectively analyzed. Biopsy material was collected with a 16-20 G Tru-Core needle (10-15 cm; Angiotech, Vancouver, CA) using a coaxial system and automatic biopsy gun. When direct access to the lesion was not possible, indirect (transgastric or transhepatic) access or hydrodissection and/or pneumodissection maneuvers were used. Characteristics of the patients, lesions, procedures, and histologic results were recorded using a standardized form. RESULTS: A total of 103 procedures included in the study were performed on patients with a mean age of 64.8 year (range: 39-94 year). The mean size of the pancreatic lesions was 45.5 mm (range: 15-195 mm). Most (75/103, 72.8%) procedures were performed via direct access, though hydrodissection and/or pneumodissection were used in 22.2% (23/103) of cases and indirect transhepatic or transgastric access was used in 4.8% (5/103) of cases. Histologic analysis was performed on all biopsies, and diagnoses were conclusive in 98.1% (101/103) of cases, confirming 3.9% (4/103) of tumors were benign and 94.2% (97/103) were malignant; results were atypical in 1.9% (2/103) of cases, requiring a repeat biopsy to diagnose a neuroendocrine tumor, and surgical resection to confirm a primary adenocarcinoma. Only mild/moderate complications were observed in 9/103 patients (8.7%), and they were more commonly associated with biopsies of lesions located in the head/uncinate process (n = 8), than of those located in the body/tail (n = 1) of the pancreas, but this difference was not significant. CONCLUSION: CT-guided biopsy of a pancreatic lesion is a safe procedure with a high success rate, and is an excellent option for minimally invasive diagnosis.

Preoperative computed tomography-guided localization of ground-glass opacities with metallic clip.

Intraoperative localization of ground-glass opacities is difficult because they are not easy to palpate and may be invisible at radioscopy. Therefore, various techniques have been developed to improve intraoperative localization of these lesions, allowing an adequate surgical resection. The aim of this study is to report two cases of preoperative localization of ground-glass opacities through computed tomography-guided placement of a metallic clip inside the lesion and to discuss this new technique in comparison with those previously described.