Value of diffusion-weighted imaging combined with conventional magnetic resonance imaging in the diagnosis of thecomas/fibrothecomas and their differential diagnosis with malignant pelvic solid tumors.

BACKGROUND: Our study aims to determine the value of diffusion-weighted imaging (DWI) combined with conventional magnetic resonance imaging (MRI) in the diagnosis of thecomas/fibrothecomas and their differential diagnosis with malignant pelvic solid tumors. METHODS: In total, 36 thecomas/fibrothecomas and 40 malignant pelvic solid tumors were included in our study. All patients underwent 1.5 T conventional MRI and DWI examinations except one patient with a fibrothecoma in whom DWI examination was not performed. The clinical features and characteristics of conventional MRI and DWI of these two groups were analyzed. Apparent diffusion coefficient (ADC) values were measured and compared between groups. Univariate analysis, multivariate logistic regression analysis, and the receiver operating characteristic curve were used for statistical analysis. RESULTS: All the thecomas/fibrothecomas showed isointensity on T1 weighted imaging (T1WI) and 77.8% (28/36) lesions showed hypo- to isointensity on T2 weighted imaging (T2WI). After administration of contrast medium, 94.4% (34/36) tumors appeared as minor to mild enhancement. On DWI, they showed a diversity of low to very high signal intensity. All malignant pelvic masses manifested as hyperintensity on T2WI and 87.5% (35/40) tumors showed very high signal (grade 3) on DWI. Higher area under the curve (AUC) and specificity could be achieved by using the lowest ADC value than the mean ADC value. Multivariate logistic regression analysis showed that shape, signal intensity on T2WI, capsule, and the lowest ADC value were the important indicators in discriminating thecomas/fibrothecomas from malignant pelvic solid tumors. CONCLUSIONS: The combination of DWI and conventional MRI is of great value in the diagnosis of thecomas/fibrothecomas and their differential diagnosis with malignant pelvic solid tumors.

Papillary meningioma: an aggressive variant meningioma with clinical features and treatment: a retrospective study of 10 cases.

INTRODUCTION: Papillary meningioma is a rare subtype of malignant meningiomas. The aim of this retrospective study was to investigate the clinical, radiological, histopathological features and prognosis for papillary meningioma at our institutions. MATERIALS AND METHODS: Ten patients with clinically, radiologically and histopathologically confirmed papillary meningiomas were treated at our hospitals. The clinical data, imaging characteristics, histopathological features, surgical treatment and postoperative follow-up, were analyzed retrospectively. RESULTS: The patients with a mean age of 36.9 years at the time of their initial operations. The papillary meningiomas were predominantly located in the convexity (n = 6). At their initial operation, six patients underwent gross total resection and four patients underwent subtotal resection. The mean post-operative follow-up period was 42.6 months (range: 12-90 months). Six patients underwent multiple surgical resections. The mean time to first recurrence was 21.5 months. On magnetic resonance imaging scan, marked enhancements and dural tail signs were displayed in all lesions. All lesions showed peritumoral edema. Cysts were seen in four lesions. Bone hyperostosis or destruction was seen in six lesions. Cerebrospinal fluid dissemination was seen in three lesions. Incomplete surgical resection was associated with recurrence. MIB-1 labeling index was associated with progression-free survival for patients (p = 0.0442). CONCLUSIONS: Papillary meningioma has a tendency to present in middle-aged patients, and it has specific clinical and histopathological characteristics. MIB-1 labeling index and the extent of resection might predict the recurrence. Cystic formation, peritumoral edema, osseous change and CSF dissemination might be neuroimaging characteristics of papillary meningioma, especially in recurrence papillary meningioma.

Whole exome sequencing reveals novel COL4A3 and COL4A4 mutations and resolves diagnosis in Chinese families with kidney disease.

BACKGROUND: Collagen IV-related nephropathies, including thin basement membrane nephropathy and Alport Syndrome (AS), are caused by defects in the genes COL4A3, COL4A4 and COL4A5. Diagnosis of these conditions can be hindered by variable penetrance and the presence of non-specific clinical or pathological features. METHODS: Three families with unexplained inherited kidney disease were recruited from Shanghai, China. Whole exome sequencing (WES) was performed in the index case from each family and co-segregation of candidate pathogenic mutations was tested by Sanger sequencing. RESULTS: We identified COL4A4 missense variants [c.G2636A (p.Gly879Glu) and c.C4715T (p.Pro1572Leu)] in the 21-year-old male proband from family 1, who had been diagnosed with mesangial proliferative nephropathy at age 14. COL4A4 c.G2636A, a novel variant, co-segregated with renal disease among maternal relatives. COL4A4 c.C4715T has previously been associated with autosomal recessive AS and was inherited from his clinically unaffected father. In family 2, a novel COL4A3 missense mutation c.G2290A (p.Gly997Glu) was identified in a 45-year-old male diagnosed with focal segmental glomerulosclerosis and was present in all his affected family members, who exhibited disease ranging from isolated microscopic hematuria to end stage renal disease (ESRD). In family 3, ESRD occurred in both male and females who were found to harbor a known AS-causing COL4A5 donor splice site mutation (c.687+1G>A). None of these variants were detected among 100 healthy Chinese individuals. CONCLUSION: WES identified 2 novel and 2 known pathogenic COL4A3/COL4A4/COL4A5 mutations in 3 families with previously unexplained inherited kidney disease. These findings highlight the clinical range of collagen IV-related nephropathies and resolved diagnostic confusion arising from atypical or incomplete clinical/histological findings, allowing appropriate counselling and treatment advice to be given.

Role of apparent diffusion coefficients with diffusion-weighted magnetic resonance imaging in differentiating between benign and malignant bone tumors.

BACKGROUND: Benign and malignant bone tumors can present similar imaging features. This study aims to evaluate the significance of apparent diffusion coefficients (ADC) in differentiating between benign and malignant bone tumors. METHODS: A total of 187 patients with 198 bone masses underwent diffusion-weighted (DW) magnetic resonance (MR) imaging. The ADC values in the solid components of the bone masses were assessed. Statistical differences between the mean ADC values in the different tumor types were determined by Student's t-test. RESULTS: Histological analysis showed that 84/198 (42.4%) of the bone masses were benign and 114/198 (57.6%) were malignant. There was a significant difference between the mean ADC values in the benign and malignant bone lesions (P<0.05). However, no significant difference was found in the mean ADC value between non-ossifying fibromas, osteofibrous dysplasia, and malignant bone tumors. When an ADC cutoff value≥1.10×10(-3) mm2/s was applied, malignant bone lesions were excluded with a sensitivity of 89.7%, a specificity of 84.5%, a positive predictive value of 82.6%, and a negative predictive value of 95.3%. CONCLUSIONS: The combination of DW imaging with ADC quantification and T2-weighted signal characteristics of the solid components in lesions can facilitate differentiation between benign and malignant bone tumors.

Nasal chondromesenchymal hamartoma in young children: CT and MRI findings and review of the literature.

BACKGROUND: Nasal chondromesenchymal hamartoma (NCMH) is an extremely rare benign tumor, primarily diagnosed in young infants and children and it often simulates malignant tumors on imaging. CASE PRESENTATION: We present computerized tomography and magnetic resonance imaging findings of two nasal chondromesenchymal hamartomas in a 5-year-old boy and a 6-week-old girl. CONCLUSIONS: NCMH is a rare, benign tumor-like lesion with good biologic behavior. No recurrence after complete resection or malignant transformation of NCMH has been reported. A correct diagnosis is imperative to avoid unnecessary adjuvant therapy.

[Primitive neuroectodermal tumor of central nervous system with features of ependymoblastoma and neuroblastoma: a clinicopathologic study of 4 cases].

OBJECTIVE: To study clinicopathologic features, immunohistochemical profile, diagnosis and differential diagnosis of childhood central nervous system primitive neuroectodermal tumors (CNS PNETs) with the features of ependymoblastoma and neuroblastoma. METHODS: The clinical data, morphologic and immunohistochemical features were analyzed in 4 cases of pediatric CNS PNETs with features of ependymoblastoma and neuroblastoma. EnVision method immunohistochemistry was applied. RESULTS: Four patients including three boys and one girl presented at the age from 12 month to 4 years and three tumors located in cerebrum, one in brain stem. All tumors showed typical combined histological patterns of ependymoblastoma and neuroblastoma, demonstrating zones of true rosettes, occasional pseudovascular rosettes, and undifferentiated neuroepithelial cells in a prominent background of mature neuropils. There was focal expression of glial fibrillary acidic protein (GFAP) consistent with glial differentiation and epithelial membrane antigen (EMA) consistent with ependymal differentiation. Necrosis was seen in three cases and calcification was present in one case. Immunohistochemically, the rosettes and undifferentiated neuroepithelial cells were positive for vimentin, partially positive for GFAP and EMA but negative for synaptophysin. The tumor cells were also positive for synaptophysin in neuropils. The Ki-67 label index ranged from 20% to 60%. CONCLUSIONS: CNS PNETs with the features of ependymoblastoma and neuroblastoma is a rare tumor with poor prognosis. The tumor primarily occurs in childhood, especially infant and belongs to the family of embryonal tumors of the CNS. The morphologic, immunohistochemical and genetic features are important in differential diagnosis from other tumors of the CNS.

Pelvic inflammatory disease: evaluation of diagnostic accuracy with conventional MR with added diffusion-weighted imaging.

PURPOSE: To determine the incremental value of magnetic resonance (MR) diffusion-weighted (DW) imaging for the diagnosis of pelvic inflammatory diseases (PID). MATERIALS AND METHODS: We added DW sequences to conventional MR imaging in 187 patients with clinically suspected PID. The imaging findings included shape, signal intensity on T1-weighted, T2-weighted, and DW imaging, shade in the peripheral lesions, free pelvic fluid, and lymphadenopathy. RESULTS: Laparoscopic and pathological findings confirmed the diagnosis in all patients. Conventional MR findings were consistent with a diagnosis of PID in 90.7% (117/129) and of non-PID in 93.3% (28/30) of the 159 patients. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of conventional MR imaging findings vs. the addition of DW imaging to conventional MR protocols for predicting PID were 90.7%, 93.3%, 98.3%, 70.0%, and 91.2% and 98.4%, 93.3%, 98.4%, 93.3%, and 97.5%, respectively. CONCLUSION: The addition of DW sequences to conventional MR imaging can improve the accuracy of diagnosis in PID.

Primary Endodermal Sinus Tumor of the Intraspinal Cavity: A Case Report and Review of the Literature.

Endodermal sinus tumor (EST) occurs most frequently in the gonads and is relatively rare in other sites, particularly in the spinal cavity. We report a 19-year-old woman who presented with back pain and weakness of both lower extremities who was found to have an EST in the spinal canal cavity. She had severely elevated serum alpha-fetoprotein (AFP) level at presentation. Magnetic resonance imaging (MRI) revealed the mass in the spinal canal. The tumor was excised. Serum AFP returned to normal after three cycles of chemotherapy. We describe the imaging findings and the macroscopic and microscopic features of this rare tumor. EST is a relatively rare malignant germ cell tumor that usually originates in the gonads and has poor prognosis. This is a rare case of the primary EST in the spinal canal. Radiologists need to be aware of the MRI appearance of extragonadal EST.

Imbalance of regulatory T cells to Th17 cells in IgA nephropathy.

BACKGROUND: Dysregulation of CD4 (+) T cell subsets participates in the pathogenesis of IgA nephropathy (IgAN). FoxP3 (+) regulatory T cells (Treg) and Th17 cells are two novel subsets of CD4 (+) T cells. This study aims to investigate Treg/Th17 balance in IgAN patients. METHODS: Peripheral frequencies of Th17 and Treg functional subsets - CD45RA (+) FoxP3(low) resting Treg (rTreg) and CD45RA(-)FoxP3(high) activated Treg (aTreg) were assessed in 63 adult IgAN patients. Expression of transcription factors (FoxP3 and RORγt) and related cytokines of Treg and Th17 were analysed. Renal expression of FoxP3 and IL-17A were detected by immunohistochemistry. RESULTS: Compared with normal controls, IgAN patients had decreased frequency of CD45RA(-)FoxP3(high) aTreg subset (p < 0.05), increased frequency of Th17 (p < 0.05) and decreased ratio of Treg/Th17 (p < 0.05). Frequency of aTreg subset correlated with SBP(r = - 0.57, p < 0.05), DBP (r = - 0.50, p < 0.05), eGFR (r = 0.68, p < 0.05) and 24 h proteinuria (r = - 0.58, p < 0.05). RORγtmRNA/FoxP3mRNA ratio increased in IgAN (p < 0.05). Serum IL-17A, IL-21, IL-23, IL-1ß and IL-6 elevated while IL-10 decreased in IgAN (p < 0.05), and serum IL-17A correlated with 24 h proteinuria (r = 0.35, p < 0.05). Serum TGF-ß1 wasn't different between the two groups. Renal interstitial infiltration of FoxP3 (+) mononuclear cells were observed in IgAN patients, particularly prominent in those with > 25% tubular atrophy/interstitial fibrosis. Tubular IL-17A expression was found in 34 out of 63 IgAN patients. Compared with 29 patients without IL-17A expression, these patients had lower renal function, greater proteinuria, and more severe tubulointerstitial damage. CONCLUSIONS: Imbalance of Treg/Th17 found in IgAN may play a role in disease pathogenesis and progression.

Extragastrointestinal stromal tumor of the mesoappendix: CT findings and a review of the literature.

BACKGROUND: Gastrointestinal stromal tumors (GISTs) are nonepithelial, mesenchymal neoplasms that rarely occur in children. CASE PRESENTATION: We present a unique case of a GIST that developed outside the gastrointestinal tract within the mesoappendix of a 6-year old boy. Computed tomography (CT) revealed a slightly lobulated, homogeneous soft-tissue mass, with marked contrast enhancement. CONCLUSION: This case study provides new insight into the CT appearance of extragastrointestinal stromal tumors.

Diagnostic accuracy of diffusion-weighted imaging with conventional MR imaging for differentiating complex solid and cystic ovarian tumors at 1.5T.

BACKGROUND: Preoperative characterization of complex solid and cystic adnexal masses is crucial for informing patients about possible surgical strategies. Our study aims to determine the usefulness of apparent diffusion coefficients (ADC) for characterizing complex solid and cystic adnexal masses. METHODS: One-hundred and 91 patients underwent diffusion-weighted (DW) magnetic resonance (MR) imaging of 202 ovarian masses. The mean ADC value of the solid components was measured and assessed for each ovarian mass. Differences in ADC between ovarian masses were tested using the Student's t-test. The receiver operating characteristic (ROC) was used to assess the ability of ADC to differentiate between benign and malignant complex adnexal masses. RESULTS: Eighty-five patients were premenopausal, and 106 were postmenopausal. Seventy-four of the 202 ovarian masses were benign and 128 were malignant. There was a significant difference between the mean ADC values of benign and malignant ovarian masses (p < 0.05). However, there were no significant differences in ADC values between fibrothecomas, Brenner tumors and malignant ovarian masses. The ROC analysis indicated that a cutoff ADC value of 1.20 x10-3 mm2/s may be the optimal one for differentiating between benign and malignant tumors. CONCLUSIONS: A high signal intensity within the solid component on T2WI was less frequently in benign than in malignant adnexal masses. The combination of DW imaging with ADC value measurements and T2-weighted signal characteristics of solid components is useful for differentiating between benign and malignant ovarian masses.

[Atypical teratoid/rhabdoid tumors of central nervous system in childhood: a clinical and histopathologic study of 6 cases].

OBJECTIVE: To study the clinicopathologic features, immunohistochemical findings, diagnosis and differential diagnosis of atypical teratoid/rhabdoid tumors (AT/RT) of central nervous system in childhood. METHODS: The clinicopathologic data, morphologic features and immunophenotypes were reviewed in 6 cases of AT/RT. EnVision method was applied. Antibodies include cytokeratin (CK), epithelial membrane antigen (EMA), vimentin, smooth muscle actin (SMA), muscle specific actin (MSA), glial fibrinary acid protein (GFAP), desmin, placental alkaline phosphatase (PLAP) and INI1. RESULTS: Five of the six cases of AT/RT occurred in infancy and early childhood. Histologically, the predominant component was rhabdoid cells. Cytoplasmic inclusions were present in all cases. Primitive neuroectodermal tumor (PNET) component was also identified in 5 of the 6 cases studied. Immunohistochemically, the tumor cells were positive for cytokeratin, epithelial membrane antigen and vimentin. The staining for INI1, desmin and PLAP was negative. Smooth muscle actin was expressed in 2 cases and glial fibrillary acidic protein in 5 cases. The proliferative index as demonstrated by Ki-67 staining was high. CONCLUSIONS: AT/RT is not a particularly uncommon malignancy in childhood. The histologic hallmark is the presence of rhabdoid cells with cytoplasmic inclusions. The tumor cells are positive for cytokeratin, epithelial membrane antigen and vimentin, and negative for INI1. Differential diagnosis includes PNET, medulloblastoma and medullomyoblastoma.

Malignant inguinal monophasic synovial sarcoma: report of a case and review of the literature.

BACKGROUND: A synovial sarcoma (SS) is an aggressive soft tissue tumor that classically occurs in the extremities near, but rarely within large joints, in young adults. Variable symptoms and clinical manifestations may be encountered and a definite diagnosis should depend on pathological results. This poses certain difficulties in arriving at a prompt diagnosis and appropriate treatment. CASE PRESENTATION: We report the case of a 68-year-old woman patient who presented an inguinal mass with swelling and pain in the right lower limb. She underwent surgery, and later received systematic intravenous chemotherapy. The pathological studies, especially the specific chromosomal translocation of a t(X;18) (p11.2;q11.2), confirmed the diagnosis as a synovial sarcoma. To the best of our knowledge, this is the first report of a monophasic synovial sarcoma in the inguinal region. CONCLUSION: Besides making the readership aware of the rarity of location and age of this present case, this report distinctly highlights the great value of a molecular analysis of an SYT associated genetic alteration in the diagnosis of synovial sarcoma occurring at rare sites especially when immunochemical results are equivocal.

Risk factors associated with poor response to immunosuppressive therapy in acquired aplastic anemia: A meta-analysis of retrospective studies.

Acquired aplastic anemia (AA) is a rare hematological disease characterized by bone marrow hypocellularity and varying degrees of pancytopenia. Immunosuppressive therapy (IST) is currently one of the first-line treatments for AA; however, unresponsiveness remains a major concern. Although previous studies have suggested several common risk factors for unresponsiveness, there are currently no widely accepted predictors. Therefore, a meta-analysis of clinical trials including information on factors associated with unresponsiveness of AA to IST was performed in the present study. The PubMed, Embase and Cochrane Library databases were searched for clinical studies on AA evaluating the association between risk factors and unresponsiveness to IST. After the factors were defined from the selected studies, the association between these factors and unresponsiveness to IST was analyzed using Review Manager software. A total of 10 studies comprising 1,820 cases were included in the present meta-analysis. The following factors were identified as predictors of unresponsiveness: Age (≥60 years), sex, absolute neutrophil count, severity of the disease, paroxysmal nocturnal hemoglobinuria clone, human leukocyte antigen (HLA)-DR2 and cytogenetic abnormalities (CAs). Among these factors, only age (≥60 years) [odds ratio (OR)=1.65], HLA-DR2 negativity (OR=2.72) and CAs (OR=1.93) exhibited a statistically significant association with unresponsiveness to IST (P=0.006, P=0.04 and P=0.01, respectively). In conclusion, the present meta-analysis revealed that age ≥60 years, HLA-DR2 negativity and CAs are risk factors for unresponsiveness to IST. This result may enable clinicians to select an effective therapeutic scheme for patients with AA and even provide novel clues to the pathogenesis of AA.

Low grade fibromyxoid sarcoma: problems in the diagnosis and management of a malignant tumour with bland histological appearance.

AIMS: To review the clinicopathological features and highlight the problems in the diagnosis and management of low grade fibromyxoid sarcomas (LGFMS). METHODS: Three cases of LGFMS were studied with histology and immunohistochemistry, and cytogenetics in one. The features and problems were compared with those in the literature. RESULTS: Two LGFMS had typical fibrotic and myxoid patterns showing abrupt transition from one to the other. Cellularity was low to moderate. Nuclei were medium sized and regular. In one of these the correct diagnosis was not made in the original needle biopsy resulting in inappropriate management. In the third tumour only myxoid areas were seen and the diagnosis was supported by cytogenetics showing a complex previously unreported translocation, t(7;18;16). One tumour recurred, one metastasised, and one has possible metastasis on imaging of the lungs. CONCLUSION: LGFMS is a tumour with low grade histological features but a high risk of local recurrence and a significant risk of metastasis which can be very late. There should be a high index of suspicion for this rare tumour and a low threshold for sending tissue for cytogenetics and/or molecular genetics. Special precautions should be exercised in the interpretation of small biopsies of a spindle cell lesion with bland cytological features in children. If the diagnosis is unclear there must be a detailed follow up plan with a person responsible for monitoring the plan.

Cellular magnetic resonance imaging: in vivo tracking of gastric cancer cells and detecting of lymph node metastases using microparticles of iron oxide in mice.

BACKGROUND: Monitoring the fate of implanted cells over time in an experimental animal may provide a new way to track the metastatic process. Lymph node metastase is of extremely importance for the prognostic prediction of gastric carcinoma. The aim of this study was to assess the feasibility of magnetic resonance imaging (MRI), using micron-sized superparamagnetic iron oxide particles (MPIO), for monitoring of the fate of gastric cancer cells and detecting the migration of gastric cancer cells through the lymphatic system in a mouse model. METHODS: SGC-7901 gastric cancer cells were labeled with green fluorescent MPIO. The cells were monitored in vitro at multiple time points by staining for iron-labeled cells and by flow cytometric detection of the fluorescent MPIO. MPIO-labeled cells were implanted subcutaneously into nude mice, and cellular MRI was performed at different time points until 35 days postinjection. RESULTS: The potential for retention of the iron particles in vitro was evaluated. Our results showed that the labeling and uptake efficiency of MPIO reached 90.0% after 24 hrs of incubation, and a small percentage of cells that retained MPIO could be examined until 16 days after labeling. In vivo MRI-based tracking over several weeks in mice revealed regions of signal loss in the primary tumors for up to 5 weeks. Furthermore, small regions of signal void were detected in images of the inguinal lymph nodes in three mice at day 28 postinjection or later, and histological assays confirmed the presence of iron-labeled cancer cells. CONCLUSION: This study supports MPIO-based cell tracking is a useful tool for monitoring the fate of gastric cancer cells in mice over time, which may facilitate progress in understanding the mechanisms of early regional lymph node micrometastases.

Oesophagitis in children: reflux or allergy?

The prevalence of eosinophilic oesophagitis appears to be increasing in many countries, sometimes rapidly, although this may be partly due to increased disease recognition. Histological methods of assessment and diagnostic criteria vary considerably between major clinical centres. Oesophagitis with over 20 intraepithelial eosinophils per high power field is more likely to be due to allergy than gastro-oesophageal reflux induced acid-peptic mucosal injury. Typical eosinophilic oesophagitis shows involvement of the entire oesophagus, with basal cell proliferation occupying more than 50% of the thickness of the surface epithelium, and high numbers of intraepithelial eosinophils, sometimes concentrated on the surface or as contiguous clusters. Ulceration and prominent neutrophils are atypical and should suggest an alternative or co-existent disease. On endoscopy, the oesophagus may display the typical 'corrugated' mucosal appearance. Clinically, dysphagia or food impaction are the most characteristic symptoms. There is a strong association with other atopic diseases, especially asthma and eczema. To date no evidence has emerged of an increased malignancy risk. Patients with eosinophilic oesophagitis typically fail to respond to acid suppressive medications but respond well to either elemental/elimination diets or aerosolised swallowed corticosteroids. Long-term uncontrolled oesophageal eosinophilic inflammation may lead to progressive subepithelial fibrosis, potentially resulting in strictures or oesophageal narrowing.

Rhabdoid tumour: a malignancy of early childhood with variable primary site, histology and clinical behaviour.

AIMS: To correlate the immunostaining for INI1 protein and mutations in INI1 gene in possible rhabdoid tumours (RT) and atypical teratoid/rhabdoid tumours (AT/RT) seen at the Royal Children's Hospital in the last 10 years, and to study the clinicopathological features of those patients with negative nuclear staining. METHODS: Twenty tumours showing suggestive histological and/or immunohistochemical features of RT and AT/RT were selected. Immunohistochemistry for INI1 and molecular investigations for INI1 mutations were performed. The clinical features, histology and immunohistochemistry in those patients with negative nuclear staining were studied. RESULTS: In seven tumours the nuclei stained uniformly for INI1. In none of these was an INI1 mutation detected. In 13 tumours nuclei showed no staining. In only ten of these was material available for molecular studies. Mutations were detected in nine. In these 13 patients, the primary tumour was in the central nervous system (CNS) in seven, in the soft tissue in three, in the liver in two and in the kidney in one. The age of presentation varied from 19 days to 7 years. Only five tumours showed large areas of rhabdoid cells. Most showed extensive non-diagnostic areas. In two an alternative diagnosis, ependymoma or myoepithelial carcinoma of soft tissue, was initially suggested. All the CNS tumours were positive for EMA, GFAP, and SMA. There were no long term survivors, but an occasional patient showed excellent response to intensive chemotherapy. CONCLUSIONS: In this small series, there is a strong correlation between the loss of INI1 immunostaining and the presence of an INI1 mutation suggesting that the former is a reliable marker for RT and AT/RT in children. As relatively few tumours showed uniform populations of rhabdoid cells, and some showed features suggesting another diagnosis, INI1 staining should be checked in all high grade CNS tumours and malignant extraCNS tumours where the diagnosis is unclear. The prognosis of RT is poor but medium term remission can be achieved in some patients with aggressive treatment.

A correlation research of Ki67 index, CT features, and risk stratification in gastrointestinal stromal tumor.

BACKGROUND AND OBJECTIVES: Recurrence and metastasis are the most important factors affecting the quality of life and survival rate of patients with gastrointestinal stromal tumors (GISTs). Accurate preoperative determination of the malignant degree of GISTs and the development of a reasonable treatment plan can effectively reduce the recurrence rate. CT is currently considered the preferred imaging modality for initial assessment. Until now, there have only been a few studies investigating the relationship between CT features and recurrence of GISTs. However, the value of CT features in prognostic assessment is still unclear. In this study, we attempted to investigate the prognostic significance of CT features and the Ki67 index in GISTs. METHODS: We retrospectively analyzed the clinicopathological and imaging data for 151 patients with a histopathological diagnosis of GIST who had received contrast-enhanced CT examination and surgical resection at XinHua Hospital from October 2008 to December 2015 or Sir Run Run Shaw Hospital in 2017. Then, we explored the correlation among CT features, the Ki67 index, and risk stratification of GISTs. The correlation among CT features, the Ki67 index, and risk stratification was mainly analyzed using the Spearman rank correlation. RESULTS: The incidence of high-risk disease or metastasis was clearly higher in the group with Ki67 > 5% than that in the group with Ki67 ≤ 5% (P < 0.001). The Ki67 index was positively correlated with risk stratification (r = 0.558) or mitotic index (r = 0.619). CT imaging features including size, contour, and margin of the tumor were associated with the Ki67 index (r = 0.332, 0.333, and 0.302, respectively). The multivariate logistic regression analysis revealed that the tumor size [P = 0.043 Exp (B) = 1.150] and the presence of ulceration [P = 0.011, Exp (B) = 3.669] were effective variables in distinguishing between the groups with Ki67 ≤ 5% and >5%. The presence of necrosis or cystic degeneration, tumor contour, tumor margin, and pattern of enhancement were associated with risk stratification (r = 0.530, 0.501, 0.419, and 0.447, respectively). CONCLUSIONS: Our findings suggest that the Ki67 index is an effective complementation in predicting the prognosis of GISTs, and CT features including size, contour, and margin of the tumor, presence of necrosis or cystic degeneration, and pattern of enhancement provide evidence to support the importance of preoperative assessment.