Internal Septations Research Articles

Fibroma desmoplásico óseo: a propósito de dos casos

Desmoplastic fibroma is a rare bone tumor with benign, locally aggressive, lytic behavior. Histologically, it is very similar to the more common and better known desmoid tumor. It can occur at any site in the skeleton but is most common in the mandible or in the long bones. We present two cases; the tumor was located in the proximal tip of the fibula in one case and in the proximal tip of the femur in the other. We describe the appearance of these lesions on CT and MRI. In both cases, the lesions were lytic, expansive, with a trabeculated appearance and internal septa, and without mineralized osseous matrix. At MRI, one of the tumors was very heterogeneous, with two differentiated areas on T2-weighted sequences: the upper zone was hypointense and the lower zone showed intermediate signal intensity. We also describe the behavior of the tumor after the administration of intravenous Gadolinium: the upper zone showed no significant enhancement and the lower showed significant enhancement in the early phase.

Colorectal Lymphangioma

Lymphangiomas of the colon are historically rare benign tumors. Only 331 cases have been reported in the world medical literature between 1931 and 2004. With widespread use of colonoscopy, however, they are being found more frequently. We report the case of a 74-year-old woman in whom a colonoscopy revealed a 3 x 4-cm submucosal lesion in the cecum that was eventually diagnosed as a lymphangioma. A CT of the abdomen showed a soft-tissue mass in the cecum and a low-density hepatic lesion. An endoscopic ultrasound of the colon showed a 3 x 4-cm hypoechoic lesion with internal septa arising from the submucosal layer of the cecum. This lesion resembled a vascular malformation; therefore a biopsy specimen was not taken. Pathologic findings of a specimen taken after a subsequent right hemicolectomy identified a submucosal lymphangioma. Published reports indicate that colonoscopy cures most lesions smaller than 2.5 cm in diameter. Resection should be reserved for larger lesions or those in patients exhibiting protein-losing enteropathy.

Stress distribution in a three dimensional, geometric alveolar sac under normal and emphysematous conditions

Pulmonary emphysema is usually the result of chronic exposure to cigarette smoke in at risk individuals. To investigate the hypothesis that lung damage in emphysema results from coincident weakening in the structural properties of the tissue and increased mechanical forces--as one explanation of the continued development of pulmonary emphysema after smoking cessation--we developed a three dimensional, geometric dodecahedron-based acinar model. Using the model numerical analysis of the stress distribution in normal conditions could be compared with those resulting in emphysematous conditions. Finite element analysis was used to evaluate the model at a number of lung inflation levels, using quasi-static loading of the alveolar pressure. When internal alveolar pressure was increased along with the adjustment of the material properties to represent a weakening of one wall in the acinus, increased stress resulted at the perimeters of the weakened area. In particular this increased stress was localized at the junction points of the internal alveolar septa. It was also found that under the proposed simulated emphysematous conditions, a significant disruption in the stress distribution within the acinus model occurred at low, rather than high, lung volumes. This is supportive of the physiological observation that destruction of the diseased tissue can occur under less stress than those existing in the normal state.

Breast carcinomas with strong high‐signal intensity on T2‐weighted MR images: Pathological characteristics and differential diagnosis

To investigate the histopathological characteristics of breast carcinomas with strong high-signal intensity (SHi) on T2-weighted (T2W) MR images (T2-SHi), and discuss the differential diagnosis between T2-SHi breast carcinomas and T2-SHi fibroadenomas. Thirty of 480 breast carcinomas examined by MRI were defined as tumors with T2-SHi (defined as homogeneous higher signal intensity (SI) compared to surrounding normal breast tissue on fat-suppressed T2W imaging (T2WI). They included eight mucinous and 22 nonmucinous carcinomas. The histopathological characteristics of T2-SHi breast carcinomas, their signal-to-noise ratios (SNRs) on T2WI, contrast-enhancement patterns, and morphology were compared with those of 22 non-T2-SHi breast carcinomas and 19 T2-SHi fibroadenomas. In nonmucinous carcinomas T2-SHi was attributable to a mixture of background matrix, a higher proportion of cells than stroma, abundant cytoplasm, edematous stroma, and hemorrhage. The significantly high SNR (mean = 75) and enhancing internal septations seen in mucinous carcinomas, and the washout phenomenon, irregular border, absence of internal septation, and rim enhancement seen in nonmucinous carcinomas provide useful information for differentiating these tumors from T2-SHi fibroadenomas. A mixture of several histopathological characteristics was associated with T2-SHi breast carcinomas. The combined information from T2WI and contrast-enhanced (CE) imaging may help distinguish T2-SHi breast carcinomas from T2-SHi fibroadenomas.

Ultrasound Wall-Sign in Pulmonary Echinococcosis (New Application)

We report our experience in diagnosing pulmonary cystic echinococcosis using an ultrasound sign related to the cystic wall. 40 patients with 46 cysts, suspected of pulmonary echinococcosis, based on plain chest radiographs and clinical findings, were examined by ultrasound over a 9-year period (1996 - 2004), and followed up until discharge. We applied our long experience with echinococcal cysts utilising the wall sign (WS) to diagnose pulmonary hydatid disease. All cysts were subject to surgical removal, and postoperative histopathology was the gold standard. There were 34 (74 %) unilocular and 12 (26 %) multivesicular echinococcal cysts. In the univesicular cysts, the WS was found in 20 cases (66.7 %) while it was present in all multivesicular cysts (100 %). Following surgical removal, echinococcosis was confirmed by histopathology in all cases. We conclude that a double layered border in univesicular and double layered internal septum in multivesicular pulmonary echinococcal cysts is a reliable indicator of pulmonary echinococcosis, with a specificity of 66 % and 100 %, respectively.

Macrocystic Neoplasms of the Pancreas: CT Differentiation of Serous Oligocystic Adenoma from Mucinous Cystadenoma and Intraductal Papillary Mucinous Tumor

The purpose of our study was to determine useful CT criteria for differentiating serous oligocystic adenomas of the pancreas from other similarly presenting neoplasms, such as mucinous cystadenoma and intraductal papillary mucinous tumor of the branch duct type. Forty-one patients with histologically confirmed macrocystic neoplasms of the pancreas were enrolled: serous oligocystic adenoma in 10 patients, mucinous cystadenoma in 13, and intraductal papillary mucinous tumor in 18. Location, greatest dimension, shape, presence of mural nodules, presence of wall calcification, and the extent and degree of main pancreatic duct (MPD) dilatation were analyzed with CT. The lesions were categorized into seven groups according to their shapes: multicystic, lobulated contour with and without internal septation, smooth contour with and without internal septation, pleomorphic cystic, and clubbed fingerlike cystic. Comparative studies were performed using Fisher's exact test and the Mann-Whitney U test. Significant differences in lesion shape were found between serous oligocystic adenoma and the other macrocystic neoplasms (mucinous cystadenoma [p < 0.05], intraductal papillary mucinous tumor [p < 0.05]). Serous oligocystic adenoma had a multicystic or lobulated contour with or without septation, whereas mucinous cystadenoma had a smooth contour with or without septation and intraductal papillary mucinous tumor had either a pleomorphic or a clubbed fingerlike cystic shape. Serous oligocystic adenoma showed proximal MPD dilatation from the lesion, whereas intraductal papillary mucinous tumor showed distal or whole MPD dilatation (p < 0.05). No significant difference was apparent among the three diseases in terms of location, greatest dimension, or presence of calcification or mural nodules. Serous oligocystic adenoma of the pancreas has characteristic CT findings that differentiate it from other cystic tumors. It appears as a multicystic or lobulated cystic lesion with septation.

Giant Neurocysticercosis Cyst in the Cerebellar Hemisphere-Case Report-

A 67-year-old man presented with dizziness, nausea, and ataxia. Magnetic resonance imaging showed a large (5.5 x 4 x 4 cm) cystic lesion in the left cerebellar hemisphere with internal septation, a mural nodule, and thin rim enhancement. Cystic cerebellar tumor such as hemangioblastoma was initially suspected. Following surgery, the cyst was identified as cerebellar neurocysticercosis. Neurocysticercosis is the most common parasitic disease of the central nervous system but is occasionally misdiagnosed as tumor because of the varying neuroimaging presentation. This case shows that neurocysticercosis should be considered in the differential diagnosis of giant cystic lesions in the cerebellum as surgical intervention may be unnecessary.

Diagnostic Architectural and Dynamic Features at Breast MR Imaging: Multicenter Study

To prospectively determine the prevalence and predictive value of three-dimensional (3D) and dynamic breast magnetic resonance (MR) imaging and contrast material kinetic features alone and as part of predictive diagnostic models. The study protocol was approved by the institutional review board or ethics committees of all participating institutions, and informed consent was obtained from all participants. Although study data collection was performed before HIPAA went into effect, standards that would be compliant with HIPAA were adhered to. Data from the International Breast MR Consortium trial 6883 were used in the analysis. Women underwent 3D (minimum spatial resolution, 0.7 x 1.4 x 3 mm; minimal temporal resolution, 4 minutes) and dynamic two-dimensional (temporal resolution, 15 seconds) MR imaging examinations. Readers rated enhancement shape, enhancement distribution, border architecture, enhancement intensity, presence of rim enhancement or internal septations, and the shape of the contrast material kinetic curve. Regression was performed for each feature individually and after adjustment for associated mammographic findings. Multivariate models were also constructed from multiple architectural and dynamic features. Areas under the receiver operating characteristic curve (Az values) were estimated for all models. There were 995 lesions in 854 women (mean age, 53 years +/- 12 [standard deviation]; range, 18-80 years) for whom pathology data were available. The absence of enhancement was associated with an 88% negative predictive value for cancer. Qualitative characterization of the dynamic enhancement pattern was associated with an Az value of 0.66 across all lesion architectures. Focal mass margins (Az = 0.76) and signal intensity (Az = 0.70) were highly predictive imaging features. Multivariate models were constructed with an Az value of 0.880. Architectural and dynamic features are important in breast MR imaging interpretation. Multivariate models involving feature assessment have a diagnostic accuracy superior to that of qualitative characterization of the dynamic enhancement pattern.

Ovarian Cysts in Young Girls with Hypothyroidism: Follow-up and Effect of Treatment

Ovarian cysts have been reported in girls with longstanding uncompensated primary hypothyroidism. Restoration of euthyroid state has been associated with resolution of these cysts; long-term follow-up of these patients is however lacking. We evaluated the outcome in ten girls with ovarian cysts and hypothyroidism managed at our hospital with special emphasis on subsequent pubertal development and ovarian imaging. Patients were diagnosed at the age of 8.6 +/- 2.3 years (mean +/- SD) with severe uncompensated primary hypothyroidism (TSH levels >100 mIU/l in all; 509.3 +/- 651 mIU/l) and growth retardation (height SDS -4.1 +/- 1.8). Nine girls had vaginal bleeding at diagnosis; five also had thelarche. LH and FSH levels were prepubertal in all patients. Ovarian cysts were bilateral in eight girls (80%); internal septation was noted in six. Thyroxine replacement (4.1 +/- 0.7 microg/kg/day) led to normalization of TSH levels with reversal of pubertal changes and regression of ovarian cysts in all patients 2.2 +/- 1.0 months after treatment. At last follow-up 3.5 +/- 2.6 years after initiation of treatment at the age of 12.0 +/- 2.3 years, all patients had normal ovarian size in ultrasound evaluation with six girls progressing to normal puberty. Our study emphasizes the need to exclude hypothyroidism in young girls with ovarian cysts. Identification of hypothyroidism in these girls obviates the need for extensive investigations.

Positive and Negative Predictive Values of BI-RADS®-MRI Descriptors for Focal Breast Masses

The purposes of this study were to evaluate the positive and negative predictive values of the BI-RADS-MR descriptors of focal masses and to develop an interpretation model based on the kinetic and morphologic parameters. Retrospective review was performed of 171 consecutive focal breast masses. MR imaging was performed on a 1.5T system using the volumetric interpolated breath-hold examination sequence (mean partition thickness, 1.2 mm; time of acquisition, 35 s). Kinetic enhancement patterns were assessed by visually comparing signal intensity on the dynamic images acquired at 60 s and 4 min (washout, plateau, and persistent). There were 126 malignant and 45 benign lesions. The most frequent morphological finding among the malignant lesions was heterogeneous internal enhancement in the delayed phase (96%; P<0.001); the most frequent finding in benign lesions was smooth margin or smooth shape/margin (80 to 82%; P<0.001). The features with the highest positive predictive value for carcinoma were spiculated margin (100%), delayed central enhancement (100%), delayed enhancing internal septations (97%), and irregular shape (97%). The characteristics with the highest diagnostic accuracy for malignancy were spiculated margin (100%) and heterogeneous enhancement following washout in the smooth shape/margin group (100%). The sensitivity, specificity, and positive and negative predictive values of an interpretation model based on a combination of the morphologic characteristics and kinetic information were 99%, 89%, 96%, and 98%, respectively. A combination of morphologic criteria, particularly lesion shape/margin and internal heterogeneity, and kinetic information is useful for differentiating benign and malignant lesions.

Gastrointestinal: Solitary fibrous tumor

A woman, aged 67, was referred for evaluation because of a mass in the left upper quadrant of her abdomen. She had noted intermittent discomfort in the region for the preceding 6 weeks. There were no other significant gastrointestinal symptoms. On examination, the mass was firm and extended for approximately 5 cm below the left costal margin. A contrast-enhanced computed tomography scan showed a mass, 13 cm in diameter, in the region of the lesser sac. The mass was predominantly of low density and had unusual internal septations (Fig. 1). The stomach was displaced anteriorly and to the right while the pancreas was displaced inferiorly. The differential diagnosis included a stromal cell tumor and sarcomas arising from the stomach, pancreas or mesentery. A barium meal radiograph was consistent with external compression of the stomach (Fig. 2). At laparotomy, a large neoplasm was removed along with the spleen and the tail of the pancreas. Histological evaluation revealed an encapsulated tumor composed of spindle cells, bands of fibrous tissue and areas of cystic degeneration. Immunohistochemical studies were positive for CD34 and bcl2 and negative for a variety of proteins including CD117 and S-100. The pathological diagnosis was that of a solitary fibrous tumor arising from the retroperitoneum. Solitary fibrous tumors are well circumscribed neoplasms with spindle cell fibrous and myofibroblastic proliferation separated by strip-like bands of collagen. They have mostly been described in the pleura but extrapleural sites include the peritoneum, retroperitoneum and mediastinum. Most of the tumors including the case described above have low mitotic rates and are considered benign. In a minority of cases, however, the neoplasms have high cellularity and high mitotic rates that are associated with higher risks for local recurrence and metastases. Immunohistochemical studies are helpful for differentiating solitary fibrous tumors from stromal cell tumors, smooth muscle tumors and benign neural tumors. The characteristic feature for solitary fibrous tumors is expression of an antigen recognized by CD34, a feature that occurs in at least 90% of specimens. Contributed by

Dynamic High-Spatial-Resolution MR Imaging of Invasive Ductal Carcinoma: Influence of Histological Scirrhous Component on MR Descriptors

The purpose of this study was to assess the relationship between the amount of scirrhous component in invasive ductal carcinoma and its MR characteristics. We retrospectively reviewed 71 consecutive patients with invasive ductal carcinoma smaller than 25 mm (average, 16.6 mm) in diameter. The scirrhous component was defined as invasive foci in small clusters of cancer cells showing desmoplasia. Invasive ductal carcinoma was subclassified into 3 groups in accordance with the amount of the scirrhous component (scirrhous component degree; SCD): SCD I (scirrhous component less than 20%), SCD II (intermediate), and SCD III (more than 80%). Dynamic magnetic resonance (MR) imaging was performed using volumetric interpolated sequence. Prior to dynamic study, T2*-weighted first-pass perfusion images were obtained before, during, and after bolus injection of 0.1 mmol Gd-DTPA/kg. Twenty-eight lesions were classified as SCD I, 14 as SCD II, and 29 as SCD III. Mass margin and signal intensity loss in the perfusion study were significantly different among the 3 SCD groups (P<0.001). The kinetic patterns were significantly different among the 3 SCD groups (P=0.04), and between SCD I/II and SCD III (P=0.03). The presence of enhancing internal septations was significantly different between SCD I/II and SCD III carcinomas (P=0.05). Central enhancement was only observed in SCD I carcinoma (4%; 3/71). The histological predominance of the scirrhous component in invasive ductal carcinoma may be one explanation for the differences in morphologic and kinetic patterns on MR imaging.

OVARIAN TUMOURS

Objectives: To correlate preoperative diagnosis with operative findingsregarding the type of ovarian tumours. Material and Methods: Setting: Gynaecology Unit-I, Nishtar Hospital, Multan.Sample size: 50 patients. Duration: One year from October 2001 to October 2002. Study Design: A prospectiveanalytical study. Results: Most common age group in benign tumours was 20-40 years. 50% of patients with malignanttumours were between 30-50 years. Out of 50 patients, 33.3% benign tumours were in unmarried girls. Only 5% ofcancers were in nullipara, while 80% of patients had two or more children. Most common presenting symptom wasabdominal/pelvic pain. Abdominal distension was present in 75% of malignant cases. Pressure effects, metastaticsymptoms and general symptoms were more frequently seen in malignant than benign cases. On ultrasonography,benign tumours were cystic in 83.3% of patients and 46% of these cystic tumours had either internal septations orechoes. 85% of malignant tumours were either solid or mixed. Ascites was detected in 60% of cancers. Abdominalascites was found in 75% of malignant cases intra-operatively. Irregular tumours and those with surface adhesionswere more likely to be malignant. The accuracy of preoperative diagnosis was found to be 84%, 5 cases initiallyconsidered malignant were later on found to be benign, while 3 cases diagnosed as benign preoperatively provedmalignant. Out of 50 cases, 46 (92%) cases were diagnosed as epithelial cell tumour on histopathology, while 4 cases(8%) were germ cell tumours. Conclusion: It was concluded that identification of risk factors, detailed enquiry of thepresenting symptoms and proper clinical examination of the tumour provide important information about the type ofovarian tumour. Ultrasonography is the best preoperative technique available to differentiate benign from malignantovarian tumours.

Review of complex breast cysts: implications for cancer detection and clinical practice

The use of ultrasound in breast diagnosis has resulted in the increasing identification of incidental benign-appearing lesions, of which complex (or atypical) breast cysts are frequently reported. Complex breast cysts were estimated to be reported in approximately 5% of breast ultrasound examinations. A systematic review of the literature on sonographically detected complex breast cysts was carried out. The quality of primary studies and extracted data on cancer detection was assessed. Very few studies have examined complex breast cysts and quantified the associated cancer detection rate. In most of these studies, subjects have been selected on the basis of progress to intervention, which would overestimate the likelihood of malignancy. The only study to examine complex cysts from all consecutive ultrasounds reported one case of non-invasive cancer from 308 lesions--0.3% (95% confidence interval, 0.01-1.84). Ultrasound features associated with a higher risk of the lesion being a cancer are: thickened walls, thick internal septations, a mix of cystic and solid components, and an imaging classification of indeterminate. Using the information from the present review, complex breast cysts were categorized on the basis of associated risk of malignancy, and an approach to the management of these lesions to assist clinical decision-making was suggested. Provided adequate information is given to the patient, complex breast cysts with a very low risk of malignancy do not always require image-guided biopsy.

Differentiation of Phyllodes Breast Tumors from Fibroadenomas on MRI

The purpose of our study was to evaluate the MRI appearance of phyllodes breast tumors and to differentiate them from fibroadenomas. MR images were obtained on a 1.5-T imager. T1- and T2-weighted sequences and dynamic 2D fast-field echo T1-weighted sequences were performed. MR images of 23 patients with 24 phyllodes breast tumors (one malignant, 23 benign) were analyzed with respect to morphology and contrast enhancement. The tumors were compared with the MRI appearance of 81 fibroadenomas of 75 patients. Well-defined margins were seen in 87.5% of the phyllodes tumors and 70.4% of the fibroadenomas, and a round or lobulated shape in 100% and 90.1%, respectively. A heterogeneous internal structure was observed in 70.8% of phyllodes tumors and in 49.4% of fibroadenomas. Nonenhancing internal septations were found in 45.8% of phyllodes tumors and 27.2% of fibroadenomas. A significantly greater increase in signal was seen on T2-weighted images in the tissue surrounding phyllodes tumors (21%) compared with fibroadenomas (1.2%). Most of both lesions appeared with low signal intensity on T1- and T2-weighted images. After the administration of contrast material, 33.3% of phyllodes tumors and 22.2% of fibroadenomas showed a suspicious signal intensity-time course. Phyllodes breast tumors and other fibroadenomas cannot be precisely differentiated on breast MRI. Phyllodes tumors have benign morphologic features and contrast enhancement characteristics suggestive of malignancy in 33% of cases.

Dynamic Bilateral Contrast-enhanced MR Imaging of the Breast: Trade-off between Spatial and Temporal Resolution

To investigate prospectively the trade-off between temporal and spatial resolution in dynamic contrast material-enhanced bilateral magnetic resonance (MR) imaging of the breast. Informed consent and institutional review board approval were obtained. An intraindividual comparative study was performed in 30 patients (mean age, 53 years; age range, 27-70 years) with a total of 54 enhancing lesions (28 benign and 26 malignant) who underwent dynamic MR imaging of the breast twice, once with a standard dynamic protocol (256 x 256 matrix, 69 seconds per acquisition) and once on a separate day with a modified dynamic protocol (400 x 512 matrix, 116 seconds per acquisition). Systematic qualitative analysis of morphologic features and region-of-interest-based analysis of enhancement kinetics were performed. A statistically significant difference (generalized linear modeling) in enhancement rates of benign versus malignant lesions was lost when moving from the standard to the modified dynamic protocol. Kinetic information on signal intensity time course patterns was preserved. Delineation of lesion margins and internal architecture was clearly superior with the modified dynamic protocol, which allowed identification of lesion features associated with high positive predictive value or high negative predictive value for breast cancer. Ten benign lesions classified as Breast Imaging Reporting and Data System (BI-RADS) category 3 with the standard protocol were correctly downgraded to BI-RADS category 2 with the modified protocol owing to visualization of internal septations. Thirteen malignant lesions categorized as BI-RADS category 3 or 4 with the standard protocol were correctly upgraded to BI-RADS category 4 or 5 with the modified protocol owing to visualization of spicules or rim enhancement. Receiver operating characteristic analysis revealed a significantly larger area under the curve for results obtained with the modified dynamic protocol. Increased spatial resolution significantly improves diagnostic confidence and accuracy at dynamic MR imaging, even if this improvement occurs at the expense of temporal resolution. Loss of kinetic information regarding enhancement rates proved to be not diagnostically relevant because enhancement rates showed broad overlap between benign and malignant lesions and were therefore of only limited diagnostic use in the individual patient. Kinetic information regarding time course pattern was preserved and confirmed as having high specificity and high positive predictive value.

Effective Treatment of Biliary Cystadenoma

Evaluate experience over 15 years with treatment of this lesion. Biliary cystadenoma, a benign hepatic tumor arising from Von Meyenberg complexes, usually present as septated intrahepatic cystic lesions. Data were collected concurrently and retrospectively on patients identified from hospital medical records reviewed for pertinent International Classification of Diseases, Ninth Revision, Clinical Modification and CPT codes, pathology logs, and from operative case logs. Pathology specimens were rereviewed to confirm the diagnosis of biliary cystadenoma or biliary cystadenocarcinoma by 2 GI pathologists. From October 1989 to April 2004 at our institution, 19 (18F:1M) patients had pathologically confirmed biliary cystadenomas, including one with a biliary cystadenocarcinoma. The mean age was 48 +/- 15 years at initial evaluation. Complaints included abdominal pain in 74%, abdominal distension in 26%, and nausea/vomiting in 11%. Only 1 patient presented with an incidental finding. Symptoms had been present for 3 +/- 5 years, with 1 to 4 different surgeons and many other physicians involved in the diagnosis or treatment prior to definitive ablation. Eight patients had undergone 20 previous treatments, including multiple percutaneous aspirations in 4 and 11 operative procedures. CT or US was diagnostic in 95%, with internal septations present in the hepatic cysts. Definitive operative intervention consisted of hepatic resection in 12 patients, enucleation in 6 patients, and fenestration and complete fulguration in 1 patient. There were no perioperative deaths. No recurrences were observed after definitive therapy, with follow-up of 4 +/- 4 years. Biliary cystadenoma must be recognized and treated differently than most hepatic cysts. There remains a need for education about the imaging findings for biliary cystadenoma to reduce the demonstrated delay in appropriate treatment. Traditional treatment of simple cysts such as aspiration, drainage, and marsupialization results in near universal recurrence and occasional malignant degeneration. This experience demonstrates effective options include total ablation by standard hepatic resection and cyst enucleation.

Cystadenoma and Cystadenocarcinoma of the Liver: A Single Center Experience

Biliary cystadenomas and cystadenocarcinomas comprise 5% of cystic lesions in the liver. Cystadenomas are often incorrectly diagnosed as simple cysts, which results in inadequate therapy. Recurrence and possible malignant transformation are consequences of incomplete excision. Cystadenocarcinomas are very rare tumors that are felt to be biologically indolent. A retrospective review of 18 cystadenomas and 4 cystadenocarcinomas treated at the Cleveland Clinic from July 1985 to November 2002. All 18 patients with cystadenomas were women; mean age was 48 years. The majority (16 of 18) were symptomatic. Preoperative CT scans demonstrated cyst(s) with septations in all patients. Fifty-five percent had undergone prior intervention(s) to treat the cyst. Thirteen patients had complete excision of the cystadenoma, either by enucleation or liver resection. None of the patients developed recurrent cystadenomas (mean followup 37 months). Of 4 patients with cystadenocarcinoma, 3 were women; mean age was 60 years. All were symptomatic. Preoperative CT scans demonstrated masses with both cystic and solid components. No patient had undergone prior intervention. All had a liver resection. Two patients died of metastatic disease at 6 and 12 months, respectively. One patient is alive and disease-free at 16 years; 1 is alive with metastatic disease 10 years after the liver resection. Cystadenomas are uncommon tumors that are often incorrectly diagnosed as simple cysts. Preoperative imaging that demonstrates the presence of internal septations highly suggests the diagnosis of cystadenoma. Intraoperative biopsy and frozen section(s) are essential, although they are not 100% accurate. Cystadenomas require complete excision to prevent recurrence and the possibility of malignant transformation. Cystadenocarcinomas are very rare. Despite complete resection, cystadenocarcinomas can recur in a short period of time. The biologic behavior of these tumors can vary widely.

Can EUS Help to Differentiate Macrocystic Serous Cystic Tumor From Mucinous Cystic Tumor of the Pancreas by its Morphologic Characteristics?

Background: Benign pancreatic serous cystic tumor is usually morphologically distinguishable from mucinous cystic tumor (MCT), which require resection because of its malignant potential. A macrocystic variant of serous cystic tumor (M-SCT) recently has been described, making this important distinction more difficult. The aim of this study was to determine the EUS morphologic characteristics of M-SCT that can help differentiation from MCT. Methods: Clinical and EUS morphologic characteristics were studied in 27 consecutive patients with M-SCT and MCT who underwent surgery in Asan Medical Center from January 2001 to August 2004. EUS morphology was focused on several parameters including presence of microcysts (millimetric cysts around major cyst), configuration of cyst, septum-forming cyst (cyst or cyst-like lesion formed by internal septation within cyst). Results: Resection specimens were available for 10 M-SCTs and 17 MCTs. Significant differences were observed with regard to age (44.9 for M-SCT vs. 54.8 for MCT, p = 0.03) and location within the pancreas (80% in head for M-SCT vs. 82% in body or tail for MCT, p = 0.03). There were no significant differences of EUS morphologic characteristics between both groups regarding the type of loculation, presence of mural nodule and cyst wall, and echo-pattern of cyst contents. But, most of M-SCT had microcysts (80%) when compared with 18% of MCT (p = 0.02), and lobulated configuration of cyst was more frequently seen in M-SCT than MCT (90% vs. 18%, p = 0.001). Septum forming cyst was observed in 90% of M-SCT while it was observed in 23% of MCT (p = 0.001). The combination of microcysts, lobulated configuration of cyst, and septum-forming cyst had sensitivity of 70%, specificity of 100%, positive predictive value of 100%, and negative predictive value of 85% for the diagnosis of M-SCT compared with MCT. Conclusions: M-SCT tends to occur at relatively younger age than MCT and be located mainly in head of pancreas. Although considerable morphological overlaps occur between M-SCT and MCT on conventional imaging modalities, EUS morphologic characteristics including microcysts, lobulated configuration of cyst, and septum-forming cyst may help to differentiate M-SCT from MCT. Background: Benign pancreatic serous cystic tumor is usually morphologically distinguishable from mucinous cystic tumor (MCT), which require resection because of its malignant potential. A macrocystic variant of serous cystic tumor (M-SCT) recently has been described, making this important distinction more difficult. The aim of this study was to determine the EUS morphologic characteristics of M-SCT that can help differentiation from MCT. Methods: Clinical and EUS morphologic characteristics were studied in 27 consecutive patients with M-SCT and MCT who underwent surgery in Asan Medical Center from January 2001 to August 2004. EUS morphology was focused on several parameters including presence of microcysts (millimetric cysts around major cyst), configuration of cyst, septum-forming cyst (cyst or cyst-like lesion formed by internal septation within cyst). Results: Resection specimens were available for 10 M-SCTs and 17 MCTs. Significant differences were observed with regard to age (44.9 for M-SCT vs. 54.8 for MCT, p = 0.03) and location within the pancreas (80% in head for M-SCT vs. 82% in body or tail for MCT, p = 0.03). There were no significant differences of EUS morphologic characteristics between both groups regarding the type of loculation, presence of mural nodule and cyst wall, and echo-pattern of cyst contents. But, most of M-SCT had microcysts (80%) when compared with 18% of MCT (p = 0.02), and lobulated configuration of cyst was more frequently seen in M-SCT than MCT (90% vs. 18%, p = 0.001). Septum forming cyst was observed in 90% of M-SCT while it was observed in 23% of MCT (p = 0.001). The combination of microcysts, lobulated configuration of cyst, and septum-forming cyst had sensitivity of 70%, specificity of 100%, positive predictive value of 100%, and negative predictive value of 85% for the diagnosis of M-SCT compared with MCT. Conclusions: M-SCT tends to occur at relatively younger age than MCT and be located mainly in head of pancreas. Although considerable morphological overlaps occur between M-SCT and MCT on conventional imaging modalities, EUS morphologic characteristics including microcysts, lobulated configuration of cyst, and septum-forming cyst may help to differentiate M-SCT from MCT.

Potentially Life-Threatening Neck Abscesses: Therapeutic Management Under CT-Guided Drainage

To evaluate the effectiveness of CT-guided drainage of potentially life-threatening neck abscesses. Between September 2001 and December 2003, 15 patients presented to the emergency room with potentially life-threatening neck abscesses. Their clinical condition was critical due to the abscess size (larger than 3 cm in diameter; mean diameter 5.2 cm, SD 0.91 cm) and/or abscess location. A CT scan was carried out immediately to assess the lesion. At the same time, under CT guidance, an 8 Fr trocar-type pigtail catheter was inserted, in order to drain the abscess. The decision to drain percutaneously was based on a consensus between the surgical, infectious disease and radiology teams . The catheter was kept in place until drainage stopped, and a follow-up scan was performed. In 14 (93%) patients, the abscess was completely drained, and in 1 (7%) case the collection was still present because of multiple internal septation. That patient was treated by surgical management. The catheter was in place for a mean of 3 days (SD 0.96 day). Despite the fact that the number of our patients is small, CT-guided percutaneous drainage seems to be a fast, safe and highly effective low-cost method for the treatment of potentially life-threatening neck abscesses.