Perivascular epithelioid cell tumor of the uterus: immunohistochemical, ultrastructural and molecular study

A case of perivascular epithelioid cell tumor of the uterus is reported, occurring in a 32-year-old woman. The tumor (8.0 cm in dimension) showed exophytic growth from the outer half of the myometrium. Histopathologically, the tumor was composed of thick blood vessels and perivascular epithelioid cells. The neoplastic cells were strongly immunoreactive for HMB45 antigen, CD117 (c-kit), vimentin and the progesterone receptor, but completely negative for S-100 protein, smooth muscle actin, desmin, CD34, the estrogen receptor and p16. The Ki-67 labeling index was low (1.25%). Ultrastructurally, the neoplastic cells had numerous premelanosomes with some glycogen deposits. Single-stranded DNA conformational polymorphism of p53 and methylation-specific polymerase chain reaction of p16 revealed negative results. Definite melanosomes on electron microscopic analysis and coexpression of HMB45 antigen and stem cell factor receptor (CD117) may provide the clue to understanding perivascular epithelioid cell tumor because angiomyolipoma also coexpresses HMB45 antigen and CD117.     

Epithelioid variant of gastrointestinal stromal tumor: Diagnosis by fine-needle aspiration

Epithelioid gastrointestinal stromal tumors (GISTs) may cause significant diagnostic confusion on fine-needle aspiration (FNA) with carcinomas, neuroendocrine tumors, and melanoma, particularly when metastatic. This study characterizes the cytologic features of nine cases of epithelioid GISTs that were obtained by computerized tomographic guidance in five, by endoscopic ultrasound in three, and from an excised liver tumor in one. Six cases presented as liver masses, one as a perisplenic mass, one as an abdominal mass, and one as a gastric mass. The aspirates revealed mainly single or small clusters of epithelioid cells with a moderate amount of granular to clear cytoplasm, small uniform nuclei with mild to marked nuclear envelope irregularities. Binucleation and intranuclear inclusions were frequent findings. Collagenous stroma was seen in most cases. In three cases, a neuroendocrine tumor was the initial diagnosis. Immunocytochemical staining for c-kit (CD117) was performed on cellblocks in six cases and was positive in five cases. On the subsequent surgical specimen, CD117 was positive in the c-kit-negative cytology case. The diagnosis of GIST should be considered in aspirates of the gastrointestinal tract, liver, mesentery, or abdominal wall mass lesions when epithelioid cells are the predominant cell type. Ancillary studies such as immunohistochemical stains are usually helpful in making a definitive diagnosis.     

Gastrointestinal stromal tumor of the vermiform appendix mimicking Meckel’s diverticulum: Case report with literature review

IntroductionGastrointestinal stromal tumors (GISTs) of the appendix are extremely rare. To date, only 15 cases have been reported in the English literature. Here, we present a new case of an appendiceal GIST with appendicitis.Presentation of caseA 68-year-old man who complained of right lower abdominal tenderness underwent surgery for a cystic mass mimicking Meckel’s diverticulum. Laparoscopy revealed a mass protruding from the proximal appendix with distal appendicitis. Complete resection with adequate margins was performed. Histology showed a spindle cell GIST without mitotic activity as well as a strong expression of CD117 and CD34.ConclusionPrimary appendiceal GIST occur at a very low rate and their symptoms are nonspecific. Accordingly, rare tumors of appendix including GISTs should be considered in the differential diagnosis of atypical symptoms or image findings.     

Immunophenotype of c-kit cells in normal human bone marrow: implications for the detection of minimal residual disease in AML

Summary. In the present study, seven normal human bone marrow samples from healthy volunteers have been analysed in order to investigate the immunophenotypic characteristics of the normal CD117⁺ cells and their utility for the detection of minimal residual disease in 71 acute myeloid leukaemia patients.
Our results show that most of normal BM CD117⁺ cells coexpress the HLADR and the myeloid associated CD33 antigen. In addition, almost half of CD117⁺ cells are CD34⁺, these cells displaying a different FSC/SSC distribution when compared to the CD117⁺/CD34⁻ cells. No CD117⁺/CD15⁺ and CD117⁺/CD10⁺ cells were detected and very few CD117⁺ cells (<1 × 10⁻³) expressing the HLADR⁻/CD34⁻, CD33⁺/HLADR⁻ and CD34⁺/HLADR⁻ phenotypes were found to be present in normal BM. In contrast, from the 71 AML patients analysed, 34 had CD117⁺/CD15⁺ blast cells and eight had the CD117⁺ phenotypes detected at low frequencies (<1 × 10⁻³) in normal BM.
In summary, the present study shows that the use of the CD117 antigen in different monoclonal antibodies combinations may be of great help for the detection of minimal residual disease in a high proportion of AML cases, especially in those patients displaying the CD117⁺/CD15⁺ phenotype, because cells coexpressing both antigens in normal BM, if present, are at very low frequencies.     

Cardiovascular features of homozygous familial hypercholesterolemia: analysis of 16 patients

Familial hypercholesterolemia (FH) is characterized by an autosomal codominant inheritance, an abnormality in low-density lipoprotein (LDL) receptor function, elevated plasma cholesterol levels and premature atherosclerosis. Sixteen patients with homozygous FH were studied to correlate the extent of their atherosclerotic disease with their lipid levels and receptor function. The age range at initial presentation was 3 to 38 years (mean 12), and at the last examination, 6 to 43 years (mean 20). The mean pretreatment total plasma cholesterol concentration for all patients was 729 +/- 58 mg/dl (+/- standard error of the mean), and the mean LDL cholesterol level was 672 +/- 58 mg/dl (normal 60 to 176). High-density lipoprotein cholesterol was 28 +/- 3 mg/dl (normal 30 to 74). In the 7 patients with FH who had symptoms of myocardial ischemia (Group I), the mean pretreatment LDL cholesterol value (817 +/- 62 mg/dl) was higher than that of the 9 asymptomatic patients (Group II) (560 +/- 74 mg/dl). In Group I, 5 of 7 patients had left or right coronary ostial narrowing and 3 had significant left ventricular outflow obstruction. Most coronary arterial narrowing occurred in the right coronary and left anterior descending arteries and the least amount in the left circumflex coronary artery. A femoral bruit was the physical finding that correlated best with the Group I population; brother:sister pairs revealed a milder clinical course for the female. Seven of the 16 patients have survived into their third decade without symptoms. Comparison of these persons with those in whom angina developed reveals a marked heterogeneity in their clinical course, which appears to be associated with receptor negative/defective status.     

CD117 expression in operable oesophageal squamous cell carcinomas predicts worse clinical outcome

Aims

To investigate the aberrant expression of CD117 in oesophageal squamous cell carcinoma (SCC) and its prognostic significance.

Methods and results

Immunohistochemical staining for CD117 was performed on tissue microarray and routine tissue sections from 157 oesophageal SCC patients and 10 normal oesophageal epithelia adjacent to tumour. The positive rate of CD117 expression was 29.9% in oesophageal SCC tissues, whereas no CD117 expression was detected in the 10 normal oesophageal epithelia. CD117 expression was significantly associated with T stage (P < 0.001), distant metastasis (P = 0.015), lymph node metastasis (P = 0.019), and clinical stage (P = 0.021). Progression‐free survival in the patients with CD117‐positive tumours was shorter than that in the patients with CD117‐negative tumours (P = 0.010). In univariate analyses, CD117 expression was the most significant factor for overall survival of oesophageal SCC patients (P < 0.001), followed by lymph node metastasis (P = 0.001), T stage (P = 0.002), clinical stage (P = 0.006), distant metastasis (P = 0.020), and histological grade (P = 0.027). Multivariate analyses verified that CD117 expression was an independent prognostic marker for oesophageal SCC patients (P = 0.002). In addition, CD117 expression predicted poorer survival in patients without distant metastases.

Conclusions

CD117 expression in operable oesophageal SCC may be a valuable prognostic marker, and detection of its expression in clinical samples may be useful in defining a subclass of oesophageal SCCs with extremely poor clinical outcome, which may require a specially targeted treatment modality.     

The harmonic scalpel versus electrocautery for parotidectomy: A meta - analysis

ObjectiveParotidectomy is the most classic and unequivocal intervention for parotid neoplasm. The operative outcomes and postoperative complications of parotidectomy between harmonic scalpel and electrocautery gained more prominence in physician. In spite of much research work within the past years, there was an obvious lack of randomized controlled trial to resolve this question. Hence, a quantitative and qualitative meta-analysis was essential to evaluate the differences in these two types of hemostasis method.MethodThe major electronic databases, including Pubmed, Embase, Cochrane library, Google Scholar, China National Knowledge Infrastructure and Chinese Scientific and Technological Journal databases were using the key words “electrocautery”, “electrocoagulation”, “harmonic scalpel”, “ultrasonic scalpel”, “ultrasonic dissector”, “parotidectomy” and “parotid surgery”. 9 articles were included in our systematic review and meta-analysis. The operative time, intraoperative blood loss, hospital stay, salivary fistula and transient facial nerve paralysis were the outcome measures. Odds ratios (ORs) with 95% confidence intervals (CIs) were employed to evaluate the effect size for categorical outcomes and mean differences (MDs) with 95% confidence intervals (CIs) for continuous outcomes.ResultsIn our meta-analysis, there was a significant reduction in operation time [mean difference: ?20.97; 95%CI=(?24.02,?17.92); P < 0.00001], intraoperative blood loss [mean difference: ?20.75, 95%CI=(?22.32,?19.18); P < 0.00001], hospital stay [mean difference: ?0.83; 95%CI=(?1.10,?0.57); P < 0.00001], salivary fistula [ORs: 0.30, 95%CI=(0.08,1.14)] and transient facial nerve paralysis [OR:0.33, 95%CI=(0.19,0.58),P = 0.0001] in harmonic scalpel group compared with electrocautery group.ConclusionThis meta-analysis indicated that compared with electrocautery, harmonic scalpel (HS)was transcendent in the aspects of operative time, intraoperative blood loss, hospital stay, salivary fistula and transient facial nerve paralysis. The harmonic scalpel, as an efficient and useful instrument, was advocated in parotidectomy.