Real-world data on ALK rearrangement test in Chinese advanced non-small cell lung cancer (RATICAL): a nationwide multicenter retrospective study.

BACKGROUND: Anaplastic lymphoma kinase (ALK) test in advanced non-small cell lung cancer (NSCLC) can help physicians provide target therapies for patients harboring ALK gene rearrangement. This study aimed to investigate the real-world test patterns and positive rates of ALK gene rearrangements in advanced NSCLC. METHODS: In this real-world study (ChiCTR2000030266), patients with advanced NSCLC who underwent an ALK rearrangement test in 30 medical centers in China between October 1, 2018 and December 31, 2019 were retrospectively analyzed. Interpretation training was conducted before the study was initiated. Quality controls were performed at participating centers using immunohistochemistry (IHC)-VENTANA-D5F3. The positive ALK gene rearrangement rate and consistency rate were calculated. The associated clinicopathological characteristics of ALK gene rearrangement were investigated as well. RESULTS: The overall ALK gene rearrangement rate was 6.7% in 23,689 patients with advanced NSCLC and 8.2% in 17,436 patients with advanced lung adenocarcinoma. The quality control analysis of IHC-VENTANA-D5F3 revealed an intra-hospital consistency rate of 98.2% (879/895) and an inter-hospital consistency rate of 99.2% (646/651). IHC-VENTANA-D5F3 was used in 53.6%, real-time polymerase chain reaction (RT-PCR) in 25.4%, next-generation sequencing (NGS) in 18.3%, and fluorescence in-situ hybridization (FISH) in 15.9% in the adenocarcinoma subgroup. For specimens tested with multiple methods, the consistency rates confirmed by IHC-VENTANA-D5F3 were 98.0% (822/839) for FISH, 98.7% (1,222/1,238) for NGS, and 91.3% (146/160) for RT-PCR. The overall ALK gene rearrangement rates were higher in females, patients of ≤ 35 years old, never smokers, tumor cellularity of > 50, and metastatic specimens used for testing in the total NSCLC population and adenocarcinoma subgroup (all P < 0.05). CONCLUSIONS: This study highlights the real-world variability and challenges of ALK test in advanced NSCLC, demonstrating a predominant use of IHC-VENTANA-D5F3 with high consistency and distinct clinicopathological features in ALK-positive patients. These findings underscore the need for a consensus on optimal test practices and support the development of refined ALK test strategies to enhance diagnostic accuracy and therapeutic decision-making in NSCLC.

Duodenal Soft Tissue Sarcoma with GLI1 Gene Rearrangement: A Case Report and Literature Review.

BACKGROUND Soft tissue tumors have various subtypes, among which sarcomas exhibit high malignant potential and poor prognosis. Malignant epithelioid tumor with GLI1 alterations was originally found in myopericytoma with t(7;12) translocation. However, recent studies indicated that it is a distinct tumor type characterized by multiple nodular distributions of oval or round epithelioid cells with a rich capillary network and a lack of specific immunophenotype. There are only a few cases reported worldwide and the optimal treatment is still being explored. CASE REPORT We report the case of a 31-year-old patient who presented with severe anemia and a large soft tissue mass in the duodenum. The patient underwent surgical resection with a negative margin, and none of the 15 lymph nodes tested positive for the tumor. Postoperative pathology and FISH testing further confirmed the presence of GLI1 disruption and S-100 and SMA negativity. Genetic testing revealed the ACTB-GLI1 fusion. No specific medication was offered after the surgery. No tumor recurrence was found during the 23-month follow-up period. The patient's quality of life is currently satisfactory. CONCLUSIONS Soft tissue sarcomas characterized by GLI1 gene rearrangement have a relatively less aggressive and metastatic nature, with the solid mass spreading minimally even as it grows. Patients can benefit from surgical resection, resulting in a relatively long period of tumor-free survival.

Primary pulmonary hyalinizing clear cell carcinoma with fusions of both EWSR1::CREM and IRF2::NTRK3: report of a case with an aggressive behavior.

Primary pulmonary hyalinizing clear cell carcinoma (HCCC) is a rare salivary gland-type tumor newly recognized in recent years, with approximately 21 cases reported to date in the English literature, which constitutes a challenge in pathology diagnosis, particularly in small biopsy specimens. Here, we present a case of pulmonary HCCC diagnosed by computed tomography-guided percutaneous lung biopsy in a 70-year-old man's right lower lung. Although the morphology and immunophenotype of the tumor suggested the diagnosis of mucoepidermoid carcinoma, fluorescence in situ hybridization failed to reveal the rearrangement of MAML2 gene, which is characteristic of mucoepidermoid carcinoma. Instead, further molecular genetic testing showed that the tumor harbored a rare EWSR1::CREM fusion combined with a previously unreported IRF2::NTRK3 fusion. Pulmonary HCCC is commonly regarded as a low-grade malignant tumor with an indolent course, but this case has a different biological behavior, presenting extensive dissemination and metastases at the time of diagnosis, which expands our understanding of the prognosis of this tumor. The patient has had five cycles of combination chemotherapy and has been alive with the tumor for eight months.

A Radiomics Model Based on Gd-EOB-DTPA-Enhanced MRI for the Prediction of Microvascular Invasion in Solitary Hepatocellular Carcinoma ≤ 5 cm.

Aim: The aim of this study is to establish and validate a radiomics-based model using preoperative Gd-EOB-DTPA-enhanced MRI to predict microvascular invasion (MVI) in patients with hepatocellular carcinoma ≤ 5 cm. Methods: Clinicopathologic and MRI data of 178 patients with solitary hepatocellular carcinoma (HCC) (≤5 cm) were retrospectively collected from a single medical center between May 2017 and November 2020. Patients were randomly assigned into training and test subsets by a ratio of 7:3. Imaging features were extracted from the segmented tumor volume of interest with 1-cm expansion on arterial phase (AP) and hepatobiliary phase (HBP) images. Different models based on the significant clinical risk factors and/or selected imaging features were established and the predictive performance of the models was evaluated. Results: Three radiomics models, the AP_model, the HBP_model, and the AP+HBP_model, were constructed for MVI prediction. Among them, the AP+HBP_model outperformed the other two. When it was combined with a clinical model, consisting of tumor size and alpha-fetoprotein (AFP), the combined model (AP+HBP+Clin_model) showed an area under the curve of 0.90 and 0.70 in the training and test subsets, respectively. Its sensitivity and specificity were 0.91 and 0.76 in the training subset and 0.60 and 0.79 in the test subset, respectively. The calibration curve illustrated that the combined model possessed a good agreement between the predicted and the actual probabilities. Conclusions: The radiomics-based model combining imaging features from the arterial and hepatobiliary phases of Gd-EOB-DTPA-enhanced MRI and clinical risk factors provides an effective and reliable tool for the preoperative prediction of MVI in patients with HCC ≤ 5 cm.

Perivascular Epithelioid Cell Tumor of Urinary Bladder.

OBJECTIVES: To review the clinicopathologic features of perivascular epithelioid cell tumor (PEComa) of the urinary bladder. METHODS: Seven cases of bladder PEComa were studied by light microscopy, immunohistochemistry, and fluorescence in situ hybridization (FISH). RESULTS: In our 7 cases, 5 patients were female and 2 were male, with ages between 26 and 78 years. Patients presented with hematuria and recurrent abdominal discomfort as the main clinical symptoms. Microscopically, the epithelioid and spindle-shaped tumor cells with clear to granular eosinophilic cytoplasm were arranged in fascicular, acinar, or nested patterns. The tumor cells were positive for HMB45, melan-A, and SMA, but no TFE3 gene rearrangement was detected in any of the 7 samples by FISH. The analysis of all 35 cases from the literature and ours showed a patient age range from 16 to 78 years (mean age, 39 years), a male-to-female ratio of 1:1.3, maximal tumor diameters from 0.6 to 18.8 cm (mean, 4.5 cm). With a mean follow-up of 27 months, the recurrence, metastasis, and mortality rates were 10.7%, 10.7%, and 7.1%, respectively. CONCLUSIONS: Bladder PEComa is extremely rare, remains a diagnostic challenge, and needs more attention. Strengthening the understanding of this tumor will improve diagnostic accuracy.

The age variation of HER2 immunohistochemistry positive rate in biopsy specimens of gastric cancer.

AIMS: The aim of this study was to explore HER2 status and characteristics in biopsy specimens of gastric cancer (GC) in Chinese population. METHODS AND RESULTS: A total of 27,787 biopsy specimens of GC from 103 hospitals were obtained. Immunohistochemistry (IHC) staining of HER2 was performed. Overall HER2 IHC positive rate was 11.2 %. HER2 positive rate elevated with the increase of age in total patients and both genders. The rates were 7.1 %, 8.1 %, 9.0 %, 10.9 %, 11.8 %, 12.6 %, and 12.1 % when patient age was ≤30, 31-40, 41-50, 51-60, 61-70, 71-80, and >80, respectively (P < 0.001). In male, the rates were 6.5 %, 8.4 %, 9.6 %, 11.5 %, 12.4 %, 13.3 %, and 12.1 % (P < 0.001). In female, the rates were 7.4 %, 7.9 %, 8.0 %, 9.0 %, 9.6 %, 10.6 %, and 11.9 % (P = 0.128). The changes in male were more dramatic than in female (P < 0.001). Furthermore, the proportion of the intestinal type GCs increased with age in total patients and both genders (P < 0.001), and in male the changes were more dramatic (P < 0.001). While the proportion of the diffuse type showed the opposite tendency to that of the intestinal type (P < 0.001). HER2 IHC positive rate showed a positive correlation with the proportion of the intestinal type (r=0.986, P < 0.001), and a negative correlation with the proportion of the diffuse type (r=0.984, P < 0.001). CONCLUSIONS: The HER2 IHC positive rate showed age variation in biopsy specimens of GC. In male the variation was more dramatic than in female. The variation of HER2 positive rate can be attributed to the age variation of the Lauren subtypes.

A Renal Cell Carcinoma with Biallelic Somatic TSC2 Mutation: Clinical Study and Literature Review.

OBJECTIVE: To elucidate the effect of the biallelic somatic TSC2 mutations, identified in one adolescent patient, in renal cell carcinoma (RCC). METHODS: Mutation analyses, immunohistochemistry and real-time polymerase chain reaction (PCR) were conducted. RESULTS: Two novel somatic mutations of TSC2 in unilateral and solitary RCC samples from a 14-year-old female were identified. The pathological features suggest the tumor as a clear-cell renal cell carcinoma. In addition, immunohistochemistry revealed elevated levels of phosphorylated S6K1. Results from in vitro cellular experiments suggest that the mutant TSC2 proteins were quickly degraded and they failed to repress the phosphorylation of S6K1 and STAT3, which leads to constitutive activation of mTORC1 pathway and ultimately cause the development of RCC. CONCLUSION: Detecting TSC2 mutation in patients with early RCC onset would be beneficial and mTOR inhibitor could be a therapeutic option for TSC2 mutation-induced RCC.

Nodal follicular dendritic cell sarcoma with four atypical histomorphologic features: an unusual case report.

BACKGROUND: Follicular dendritic cell sarcoma (FDCS) is a rare malignancy. In addition to the classical histopathologic features, it has also some special morphological variants that can present a challenge in the diagnosis of this disease. CASE PRESENTATION: A 45-year-old male who presented with a left supraclavicular mass was given a final diagnosis of FDCS after lymph node biopsy. The specimen obtained during radical resection revealed five different morphologies, including the classical histological appearance and atypical areas resembling desmoplastic infiltrative carcinoma, anaplastic large cell lymphoma (ALCL), hemangiopericytoma and classical Hodgkin's lymphoma (CHL). Immunohistochemistry was notable for positive CD21 and CD23 expression across all morphologies. Given the atypical appearance and location, the specimen was initially misdiagnosed as a metastatic carcinoma based on histology alone at an outside institution. The patient eventually underwent surgical resection followed by adjuvant chemotherapy and radiation. Despite treatment, the disease progressed, and the patient passed away 36 months after surgery. CONCLUSIONS: This unusual case of FDCS contains four types of atypical histomorphologies within a single tumor specimen, including those resembling ALCL and hemangiopericytoma which are described here for the first time. Our report further expands the histopathologic spectrum of FDCS and may help assist in the diagnosis of other such challenging cases.

Mediastinal follicular dendritic cell sarcoma: a rare, potentially under-recognized, and often misdiagnosed disease.

BACKGROUND: Mediastinal follicular dendritic cell sarcoma (FDCS) is extremely rare. Due to potential under-recognization of this disease, it happens to be misdiagnosed, especially on core needle biopsy. We report 3 cases of mediastinal FDCS and provide a literature review to improve better understanding of the tumor and to reduce misdiagnosis. METHODS: Three cases of mediastinal FDCS in our clinic practice were studied, including their core needle biopsy and resected specimens, and those cases reported previously in English literature were retrieved and analyzed. RESULTS: The core needle biopsy of case 1 showed a tumor reminiscent of classical Hodgkin's lymphoma (CHL), while the resected mass was finally diagnosed with FDCS combined with hyaline-vascular Castleman's disease. Both the biopsy and resected tissue of case 2 were constitutive of the clear epithelioid cells with marked atypia. In both cases, definitive diagnoses were not made on core needle biopsy. In case 3, there were some areas morphologically similar to CHL, and some areas contained ovoid to spindle-shaped tumor cells with fascicular pattern. The analysis of 43 cases of mediastinal FDCS showed the age of patients were from 16 to 76 years old, the male to female ratio was 1.5:1, the maximal tumor diameters were 3-17 cm. 18 cases were underwent preoperative biopsy, whereas 15 (83.3%) of which were misdiagnosed initially, often as lymphoma. 32 patients had available follow-up data, the rates of recurrence, metastasis, and mortality were 12.5, 18.8 and 28.1%, respectively. Current limited data suggested no statistical differences between adverse prognosis and gender, age, tumor size, necrosis, or different therapeutics, respectively. CONCLUSIONS: Mediastinal FDCS is a rare malignancy that has yet not been fully understood and been often misdiagnosed, particularly when making a diagnosis on core needle biopsy. Increased awareness of this enigmatic tumor is crucial to avoid diagnostic pitfalls.

A Study of the Correlation of Perfusion Parameters in High-Resolution GRASP MRI With Microvascular Density in Lung Cancer.

BACKGROUND: The histological count of microvascular density (MVD) is the current clinical standard for assessing tumor angiogenesis. Although it is hypothesized that perfusion MRI can be a noninvasive alternative to MVD, there have been few studies to validate their correlations, particularly in lung cancer. PURPOSE: To investigate the correlation between MVD and perfusion parameters obtained from high-resolution GRASP (Golden-angle RAdial Sparse Parallel) dynamic contrast-enhanced (DCE)-MRI in a cohort of lung cancer patients, and to validate that GRASP MRI can serve as a free-breathing, noninvasive imaging approach for studying tumor angiogenesis. STUDY TYPE: Prospective. POPULATION: Twenty-five lung cancer patients (16 male, 9 female, mean age = 57.3 ± 11.7 years). FIELD STRENGTH/SEQUENCE: 3T MRI; a prototype golden-angle stack-of-stars sequence. ASSESSMENT: Contrast-enhanced MR data were acquired during free breathing and were reconstructed using GRASP with a temporal resolution of ∼3 sec/phase. For all data, perfusion analysis was performed using a standard Tofts model to generate the volume transfer coefficient (Ktrans ) and the interstitial volume (Ve ). The MVD of corresponding tumor specimens, obtained from Computed Tomography-guided biopsies, were counted with CD34 staining. STATISTICAL TESTS: Pearson correlation analysis; one-way analysis of variance analysis; least significant difference-t method of multiple comparisons. RESULTS: The correlation coefficient was 0.983 and 0.972 for the measurement and remeasurement of Ktrans and Ve . The mean values of Ktrans , Ve , and MVD were 0.33 ± 0.22 min-1 , 0.25 ± 0.12, and 49.68 ± 27.08 vessels/0.723 mm2 , respectively, in all patients (n = 25); 0.36 ± 0.26 min-1 , 0.27 ± 0.13, and 49.09 ± 29.84 vessels/0.723 mm2 , respectively, in adenocarcinoma (n = 15); 0.34 ± 0.17 min-1 , 0.26 ± 0.12, and 53.85 ± 23.53 vessels/0.723 mm2 , respectively, in squamous cell carcinoma (n = 8); and 0.13 ± 0.15 min-1 , 0.14 ± 0.06, and 37.20 ± 28.28 vessels/0.723 mm2 , respectively, in small-cell carcinoma (n = 2). There was a positive relationship between the Ktrans and MVD in all patients (r = 0.738, P < 0.001). DATA CONCLUSION: High spatiotemporal resolution DCE-MRI using GRASP is a promising noninvasive alternative to the histological count of MVD for assessing tumor angiogenesis in lung cancer. LEVEL OF EVIDENCE: 1 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2019;49:1186-1194.

Hepatic monotypic epithelioid angiomyolipoma with concomitant hepatocellular carcinoma.

Hepatic monotypic epithelioid angiomyolipoma (AML) is a rare lesion in which the predominant population of an epithelioid component can mimic hepatocellular carcinoma (HCC). The hepatic epithelioid AML with concomitant HCC is extremely uncommon. In this study, we present the clinical and pathologic features of a case of hepatic monotypic epithelioid AML with concomitant HCC in a 63-year-old man. Imaging examinations revealed two masses located in the liver, measuring 83×63 mm and 37×27 mm separately, which exhibited an early contrast enhancement and a rapid washout on enhanced computed tomography (CT), so that HCC with intrahepatic metastases was suspected. The small tumor was removed for intraoperative frozen section examination. Grossly, the tumor was solitary, well-circumscribed, and non-encapsulated. Microscopically, it was composed purely of a trabecular arrangement of epithelioid cells with a sinusoidal pattern. Immunohistochemically, it was positive for HMB45, Melan-A, and alpha smooth muscle actin (α-SMA). Interestingly, the large tumor has the histologic features similar to those of the small one. However, it was positive for epithelioid markers and negative for the melanocytic markers. It reminds us that there is a possibility of coexistence of HAML and HCC in the liver. We believe that this might be the first case report of a hepatic monotypic epithelioid AML with concomitant HCC. The patient gave up treatment and died in 6 months after the operation in the follow-up.

A Rare Case of Cutaneous Diffuse Large B-cell Lymphoma Presenting as a Chronic "Infectious" Skin Ulcer.

Cutaneous diffuse large B-cell lymphoma (DLBCL) usually manifests as papules, nodules, or plaques. A rare case of a patient with a chronic skin ulcer and signs and symptoms of infection, including fever and large amounts of yellow wound exudate, is presented. Fifteen (15) months before diagnosis, a 43-year-old otherwise healthy man noted soreness without apparent cause in his upper chest and a palpable 2 cm x 2 cm focal lump. The patient developed frequent fevers, and the lump enlarged over time, producing purulent exudate. For 14 months, the patient was examined and treated at 5 hospitals, but biopsies, smears, cultures, and various types of nucleic acid testing were negative. Antibiotics to treat the suspected but nonclassified infection were ineffective. Ultimately, debridement and pathological examination of necrotic tissue from the deep sinus revealed DLBCL. The patient was provided chemotherapy, surgical debridement, and negative pressure wound therapy. Wounds started to reduce in size once chemotherapy was initiated. The wound was surgically closed with a split-skin graft, and the patient was discharged 93 days following admission to the authors' facility. This case illustrates the possibility of cutaneous DLBCL in patients with chronic skin ulcers and infectious manifestation that do not respond to antibiotic therapy. Prompt deep tissue debridement and pathological examination of deep tissue will help confirm the presence of cutaneous DLBCL and guide required chemotherapy.

Perfusion Characteristics of Hepatocellular Carcinoma at Contrast-enhanced Ultrasound: Influence of the Cellular differentiation, the Tumor Size and the Underlying Hepatic Condition.

This study aimed to analyze the influence of the cellular differentiation, the tumor size and the underlying hepatic condition on the enhancement pattern of hepatocellular carcinoma (HCC) on contrast-enhanced ultrasound (CEUS). 276 patients with single lesion ≤ 5 cm who underwent CEUS exam and were pathologically confirmed as HCC were retrospectively enrolled. Enhancement patterns, washout patterns, wash-in time and washout time were observed and recorded. During the arterial phase, more poorly differentiated HCCs (42.5%) and lesions > 3 cm (35.2%) performed inhomogeneous enhancement (p < 0.05). More well differentiated HCCs (63.4%) performed late washout or no washout while compared with moderately (37.8%) or poorly (24.1%) differentiated HCCs (p < 0.05). Poorly differentiated HCCs showed the shortest washout time (83.0 ± 39.8 s), moderately differentiated HCCs showed the moderate washout time (100.4 ± 52.1 s), and well differentiated HCCs showed the longest washout time (132.3 ± 54.2 s) (p < 0.05). Lesions > 3 cm (97.2 ± 51.3 s) washed out more rapidly than lesions ≤ 3 cm (113.9 ± 53.5 s) (p < 0.05). The dynamic enhancement procedure of HCC was influenced by the cellular differentiation and the tumor size. While, hepatic background showed no influence on the dynamic enhancement of HCC.

Primary paraganglioma-like dermal melanocytic tumor with local recurrence: a case report.

Primary paraganglioma-like dermal melanocytic tumor (PDMT) is a rare dermal melanocytic tumor first recognized in 2004. The cases in previous reports suggested a benign course with a favorable prognosis. Herein, we describe a case of PDMT in the right neck from a 33-year-old man. The tumor cells with mild atypia and low level mitosis consisted of epithelioid cells or spindle cells and were divided into organoid or nest-like structures by fibrous strands and blood vessels, resembling a paraganglioma growth pattern. No necrosis was seen. These cells were positive for HMB45, Melan A, and S-100 with < 5% cells positive for Ki67. Although the morphology conformed to benign features, it recurred after 2 years. In conclusion, while more data are needed to confirm the biologic behavior of this tumor, at least a low malignant potential cannot be excluded.

Synovial sarcoma showing loss of a green signal in SS18 fluorescence in situ hybridization: a clinicopathological and molecular study of 12 cases.

The phenomenon of losing a green signal in synovial sarcoma (SS) using the SS18 break-apart probe by fluorescence in situ hybridization (FISH) has been poorly described. In this study, 12 SS with missing a green signal were identified. This series included 7 males and 5 females, aged 17 to 69 years (median, 38.5 years). The tumors involved the extremities (50%), mediastinum (16.7%), hypopharynx (8.3%), neck (8.3%), thyroid (8.3%), and retroperitoneum (8.3%). The tumors were classified as monophasic SS (58.3%) and poorly differentiated SS (41.7%). An anaplastic SS showing features of pleomorphic sarcoma was observed. Immunostaining for TLE1, BCL2, CD99, epithelial membrane antigen, cytokeratin (AE1/AE3), cytokeratin 7, S-100 protein, and CD34 was consistent with typical SS. In FISH, all the tumors showed the pattern of 1 to 3 fused signal(s) with 1 to 3 red signal(s), without corresponding a green signal. The fusion transcripts included SS18-SSX1 (8/10, 80%) and SS18-SSX2 (2/10, 20%) fusions. Median and 5-year overall survival were 19.1 months and 43.6%, respectively. In conclusion, we reported a series of SS losing a green signal in the SS18 FISH assay. We propose that this variant FISH pattern should be interpreted as a peculiar unbalanced rearrangement of the SS18 gene and subsequent SS18-SSX fusion test should be recommended. The cases in this study seem to show some unusual clinicopathological features, including unusual locations, higher proportions of poorly differentiated SS, and aggressive clinical course. However, whether this variant FISH pattern is associated with peculiar clinicopathologic features awaits larger series.

Myocyte enhancer factor 2D promotes colorectal cancer angiogenesis downstream of hypoxia-inducible factor 1α.

Myocyte enhancer factor 2D (MEF2D) is involved in many aspects of cancer progression, including cell proliferation, invasion, and migration. However, little is known about the role of MEF2D in tumor angiogenesis. Using clinical specimens, colorectal cancer (CRC) cell lines and a mouse model in the present study, we found that MEF2D expression was positively correlated with CD31-positive microvascular density in CRC tissues. MEF2D promoted tumor angiogenesis in vitro and in vivo and induced the expression of proangiogenic cytokines in CRC cells. MEF2D was found to be a downstream effector of hypoxia-inducible factor (HIF)-1α in the induction of tumor angiogenesis. HIF-1α transactivates MEF2D expression by binding to the MEF2D gene promoter. These results demonstrate that the HIF-1α/MEF2D axis can serve as a therapeutic target for the treatment of CRC.

Primary follicular dendritic cell sarcoma of the urinary bladder: the first case report and potential diagnostic pitfalls.

BACKGROUND: Extranodal follicular dendritic cell sarcoma (FDCS) is a very rare malignancy with a variable clinical course. It is often not considered and has the potential to result in a misdiagnosis of other common sarcomas or sarcomatoid carcinomas. This is particularly true with the preoperative biopsy specimen, in which the tissue sample is often small. CASE PRESENTATION: A case of FDCS in a 63-year-old woman, arising in the urinary bladder, a previously unreported site, is described. The patient presented with the typical clinical symptoms of a bladder cancer, and the morphology of the tumor was similar to a lymphoepithelioma-like carcinoma, ultimately resulting in it being misdiagnosed. The patient received radical cystectomy, without further radiotherapy or chemotherapy. Two years after operation, a metastatic tumor to the lung was found. The mass of the right main bronchus lumen was frozen and resected through bronchoscopy, and radiotherapy was performed. The patient has lived with the tumor since then. CONCLUSIONS: This paper presents the first FDCS occurring in the urinary bladder with metastasis to the lung and emphasizes potential diagnostic pitfalls.

Dynamic enhancement patterns of intrahepatic cholangiocarcinoma in cirrhosis on contrast-enhanced computed tomography: risk of misdiagnosis as hepatocellular carcinoma.

This study aimed to assess the features of intrahepatic cholangiocarcinoma (ICC) at computerized tomography (CT) and verify the risk of misdiagnosis of ICC as hepatocellular carcinoma (HCC) in cirrhosis. CT appearances of 98 histologically confirmed ICC nodules from 84 cirrhotic patients were retrospectively reviewed, taking into consideration the pattern and dynamic contrast uptake during the arterial, portal venous and delayed phases. During the arterial phase, 53 nodules (54.1%) showed peripheral rim-like enhancement, 35 (35.7%) hyperenhancement, 9 (9.2%) hypoenhancement and 1 (1.0%) isoenhancement. The ICC nodules showed heterogeneous dynamic contrast patterns, being progressive enhancement in 35 nodules (35.7%), stable enhancement in 28 nodules (28.6%), wash-in and wash-out pattern in 15 nodules (15.3%) and all other enhancement patterns in 20 nodules (20.4%). There were no significant differences in the dynamic vascular patterns of ICC according to nodule size (p > 0.05). ICC in cirrhosis has varied enhancement patterns at contrast-enhanced multiphase multidetector CT. Though the majority of ICC did not display typical radiological hallmarks of HCC, if dynamic CT scan was used as the sole modality for the non-invasive diagnosis of nodules in cirrhosis, the risk of misdiagnosis of ICC for HCC is not negligible.

Combined hepatocellular carcinoma and cholangiocarcinoma (biphenotypic) tumors: clinical characteristics, imaging features of contrast-enhanced ultrasound and computed tomography.

BACKGROUND: Combined hepatocellular-cholangiocarcinoma (cHCC-CC) is an uncommon primary liver malignancy and little known about the clinical and imaging characteristics of cHCC-CC. We aim to define the demographics, imaging features of cHCC-CC on contrast-enhanced ultrasound (CEUS) and contrast-enhanced computed tomography (CT) in this study. METHODS: From January 2005 to December 2014, 45 patients with pathologically proven cHCC-CC who underwent preoperative CEUS and 43 patients who had additional CT scan in our institution were included. A retrospective review of the imaging studies and clinical data in these patients was conducted. RESULTS: In our series, cHCC-CC accounted for 1.6 % of all primary liver malignancy. Mean age of patient with cHCC-CC was 52.8 year (range: 28-74 year) and 88.9 % (40/45) of patients were male. Thirty of forty five patients (66.7 %) had cirrhosis and 20 % (9/45) of patients had chronic hepatitis B without cirrhosis. Alpha--fetoprotein (AFP) was elevated in 62.2 % (28/45) of patients and carbohydrate antigen 19-9 (CA19-9) elevated in 22.2 % (10/45) of patients). Both AFP and CA19-9 were simultaneously elevated in 15.6 % (7/45) of patients. Enhancement pattern resembling cholangiocarcinoma (CC) was noted in 53.3 % (24/45) of patients (on CEUS and in 30.2 % (13/43) of patients at CT. Enhancement pattern resembling hepatocellular carcinoma (HCC) was observed in 42.2 % (19/45) of patients on CEUS and in 58.1 % (25/43) of patients at CT. The percentage of tumors showing CC enhancement pattern (27.9 %, 12/43) was comparable with that of tumors showing HCC enhancement pattern (44.2 %, 19/43) on both CEUS and CT (p = 0.116). Simultaneous elevation of tumor markers (AFP and CA19-9) or tumor marker elevation (AFP or CA19-9) in discordance with enhancement pattern on CEUS was demonstrated in 51.1 % (23/45) of patients and on CT in 53.5 % (23/43) of patients, which was significantly more than simultaneous elevation of tumor markers (AFP and CA19-9) alone (p = 0.000). CONCLUSIONS: The clinical characteristics of cHCC-CC are similar to those of HCC. The cHCC-CC tumors display enhancement patterns resembling CC or HCC in comparable proportion on both CEUS and CT. Combination of simultaneous elevation of tumor makers (AFP and CA19-9) and tumor mark elevation (AFP or CA19-9) in discordance with presumptive imaging findings on CEUS or CT may lead significantly more patients to be suspicious of the diagnosis of cHCC-CC.

Comparison of CT and contrast-enhanced ultrasound findings in hepatic angiomyolipoma with pathological correlations.

OBJECTIVE: To compare imaging findings of CT and contrast-enhanced US (CEUS) in hepatic angiomyolipoma (HAML) and investigate their pathological correlations. METHODS: Imaging findings and preoperative diagnosis of CT and CEUS were retrospectively compared head to head in 46 patients with 54 histologically proven HAMLs. Correlations between imaging features and preoperative diagnosis with pathological types of HAMLs were analyzed. RESULTS: Fat was detected in 100% of lipomatous type, 84.6% of mixed type, and 7.1% of myomatous type (p = 0.000) of HAML at unenhanced CT. Well-defined hyper-echogenicity was displayed in 100% of lipomatous type, 88.5% of mixed type, 50% of myomatous type, and 66.7% of angiomatous type of HAMLs at unenhanced US. More arterial hyper-enhancement was noted on CEUS (100%) than on CT (73.1%) in mixed type (p = 0.015) and in lipomatous type (90.9% vs. 9.1%, p = 0.000) of HAMLs. Washout was present in more HAMLs on CT than on CEUS (42.6% vs. 18.5%, p = 0.007). Correct preoperative diagnosis was suggested in more HAMLs of myomatous type on CEUS than on CT (42.9% vs. 0%, p = 0.016) but showed no difference in other types of HAMLs. CONCLUSION: There are considerable discrepancies between CT and CEUS findings of HAMLs, and the imaging appearance and preoperative diagnosis of HAMLs on CT and CEUS are significantly affected by pathological types of HAMLs.