Non-melanocytic mimics of melanocytic neoplasms

On histopathologic examination, many non-neoplastic conditions mimic benign or malignant neoplasms. Alternatively, some benign and malignant neoplasms can also mimic non-neoplastic lesions. This is true of all organ systemsskin is no exception. Examples of these mimickers can be found in skin lesions of almost all tissue types, including those that are melanocytic, lymphoid, epithelial, neural, vascular, neuroendocrine, and fibrohistiocytic. Melanocytic neoplasms are particularly important as it's challenging to differentiate them as being benign or malignant, and it's difficult to tell them apart from non-melanocytic neoplasms. This review illustrates examples of non-melanocytic lesions that disguise themselves as melanocytic.     

Ploidometric diagnosis of melanocytic skin neoplasms

Differential diagnostic criteria of the tumors of the melanocytic genesis are established (73 cases). Average ploidy of typical cells of a simple nevus is 2.9 +/- 0.9 c. This increased up to 4.2 +/- 1.8 c. in cells of the dysplastic nevi regardless of the dysplasia degree. Malignant melanomas had mean index of the nuclear ploidy equal to 5.94 +/- 0.23 c.     

抗体鸡尾酒法在免疫组织化学标记中的应用

肿瘤组织常含有多种抗原成分,要在一张切片上同时显示多种组织抗原,往往需要采用双标记或三标记方法。然而,反复在一张切片上进行操作容易引起脱片,从方法学角度看也颇为费时费力。为此,作者设计了抗体鸡尾酒标记法,用p53／CD34标记了325例肺、食管、胃肠、膀胱及子宫等部位的上皮性肿瘤,同步显示p53表达水平、微血管密度及脉管受累情况;用p63／α-平滑肌肌动蛋白(SMA)标记了15例乳腺病变组织,显示肌上皮细胞的基本结构。     

Fatty acid synthase expression in cutaneous melanocytic neoplasms.

Mammalian fatty acid synthase is a multifunctional enzyme complex involved in de novo synthesis of saturated fatty acids, and inhibitors of fatty acid synthase are being evaluated as potential therapeutic agents. Increased fatty acid synthase expression has been demonstrated in subsets of malignancies, including colon, breast, endometrium, prostate and ovarian carcinomas, and recently malignant melanomas. We evaluated the immunohistochemical expression of fatty acid synthase in 155 cutaneous melanocytic lesions. They included 30 congenital nevi, 19 compound nevi, 40 Spitz nevi, 48 primary melanomas, and 18 metastatic melanomas. Fatty acid synthase expression was stronger in malignant melanomas in comparison to conventional nevi and Spitz nevi, and was the highest for metastatic melanoma. Of the primary malignant melanomas, mean fatty acid synthase scores were significantly greater for Clark levels IV and V compared to Clark levels I and II (P<0.001). In addition, melanomas with Breslow thickness 0.75-1.50 mm and >1.50 mm showed significantly higher mean fatty acid synthase scores compared with those with Breslow thickness <0.75 mm (P=0.013 and <0.001, respectively). Of interest, congenital melanocytic nevi also showed strong fatty acid synthase expression, similar to that seen in metastatic melanoma. This may represent persistence of or regression to a fetal phenotype since normal fetal tissues are known to express high levels of fatty acid synthase.     

Heavily pigmented melanocytic neoplasms: comparison of two melanin-bleaching techniques and subsequent immunohistochemical staining

The effect of melanin bleaching using permanganate/oxalate and dilute hydrogen peroxide on subsequent immunohistochemical staining of heavily pigmented melanocytic neoplasms is investigated. Permanganate/oxalate precluded the use of some antibodies but allowed much faster bleaching times, whereas dilute hydrogen peroxide enabled a full range of antibodies to be used, yet bleaching times were far longer. Each technique has advantages; however, the choice of method should be determined by the nature of the information needed to make a diagnosis and the speed at which a report is required.     

Genetic changes in neoplasms arising in congenital melanocytic nevi: differences between nodular proliferations and melanomas

Large congenital melanocytic nevi (CMN) are at an increased risk of developing melanoma. Several forms of secondary proliferations can arise in congenital nevi on rare occasions. Although some of these closely resemble melanoma both clinically and histologically, metastasis is rare. We used comparative genomic hybridization to analyze chromosomal aberrations in different types of proliferations arising in CMN and compared them to typical congenital nevi, clear-cut melanomas arising in congenital nevi, as well as primary cutaneous melanomas that were not associated with a CMN. Cases of CMN and CMN with secondary proliferations were assigned to six groups according to the predominant histological pattern: group I, bland congenital nevi (n = 6); group II, congenital nevi with foci of increased cellularity (n = 4); group III, CMN with a proliferation simulating superficial spreading melanoma in situ (n = 3); group IV, CMN with a proliferation simulating nodular melanoma (n = 9); group V, proliferating neurocristic hamartoma (n = 1); and group VI, melanoma arising in congenital nevus (n = 6). No aberrations were found in groups I to III, whereas seven of nine cases of group IV, and one of one case of group V, showed aberrations. In group IV six of seven cases with aberrations (86%) showed numerical aberrations of whole chromosomes exclusively. This pattern differed significantly from the findings in melanoma that arose within CMN (n = 6), group VI, or independent of CMN (n = 122) in which only 5% showed numerical changes only. The single case in group V showed aberrations similar to melanoma. The finding of frequent numerical chromosomal aberrations in atypical nodular proliferations arising in CMN identifies these as clonal neoplasms with a genomic instability consistent with a mitotic spindle checkpoint defect. This difference compared to the aberration pattern found in melanoma might explain their more benign clinical behavior and may be of diagnostic value in ambiguous cases.     

Evaluation of telomerase activity in cutaneous melanocytic proliferations

Telomerase is an enzyme which synthesizes the telomeres, TTAGGG repeats at the end of vertebrate chromosomes. Its activity is suppressed in the majority of somatic cells, whereas it is detectable in most tumor cell lines and human cancers. Telomerase activity has been evaluated in many tumors for diagnostic purposes, and an increase thereof has been found with tumor progression. In our study we used anonisotopic polymerase chain reaction (PCR)-based TRAP (telomeric repeat amplification protocol) method to quantify the level of telomerase activity in a series of cutaneous melanocytic lesions. Thirty-three benign nevi, 8 dysplastic nevi, 38 malignant melanomas, and 4 melanoma metastases were analyzed. Mean relative telomerase activity was low in benign nevi (3.5+/-2.9), and significantly increased in dysplastic nevi (13.1+/-6.8), malignant melanomas (49.8+/-29.6), and metastases (121.2+/-11.2). In addition to the evaluation of telomerase activity as a possible diagnostic tool, its increase with tumor progression also suggest a prognostic role in cutaneous melanoma.     

Correlating array comparative genomic hybridization findings with histology and outcome in spitzoid melanocytic neoplasms

Melanocytic neoplasms with spitzoid features including spitz nevi, spitz tumors and spitzoid melanomas are commonly encountered in the practice of dermatopathology. Although many cases can be accurately diagnosed on the basis of morphology and histology, a significant number of cases may be difficult to accurately classify. Several studies have now shown that chromosomal copy number aberrations are typical of melanoma while present in only a small percent and to a limited degree in spitz nevi. In this study, we correlated the clinical, histologic and array CGH findings of 10 spiztoid melanocytic neoplasms. Our study shows that the clinical and histologic changes correlate well with the molecular findings by array CGH. Further that array CGH can be used to help classify and predict behavior of spitzoid melanocytic neoplasms. A limited variety of copy number aberrations including gains of 11p and much more rarely 7q may be seen in spitz nevi. Additionally in this report we present the first case of a typical spitz nevus with copy number gains involving both 7q and 11p. Conversely, melanomas with spitzoid features typically have multiple chromsomal copy number aberrations involving a variety of loci. A smaller number of chromosomal aberrations, possibly a single aberrant locus, may be present in spitz tumors, but their presence may predict more aggressive behavior.     

Evaluation of a serum gonococcal antibody test

The authors evaluated the Gonosticon Dri-Dot system as a tool for the determination of the prevalence of gonococcal serum antibody in two female populations. This paper discusses their findings.     

Monoclonal antibody to a human pancreatic carcinoma cell line recognizes gastrointestinal neoplasms.

A monoclonal antibody designated RWP1.1 was produced against a human pancreatic carcinoma cell line RWP1. This antibody was shown to recognize an epitope of carcinoembryonic antigen. The reactivity of the antibody was evaluated on formalin-fixed normal tissues, 86 malignant neoplasms, 10 colonic polyps, and 6 cases of chronic pancreatitis using the peroxidase anti-peroxidase technique. RWP1.1 did not react with normal tissues apart from weak staining of fetal pancreatic ducts. This antibody preferentially reacted with primary and metastatic adenocarcinomas of the colon, stomach, pancreas, and colonic polyps but not with most adenocarcinomas from other sites nor with other types of tumors or cases of chronic pancreatitis. It also reacted with colon adenocarcinomas on frozen sections. The restricted specificity of this antibody could be used in differentiating gastrointestinal adenocarcinomas from other types of tumors including adenocarcinomas from other sites and most pancreatic adenocarcinomas from chronic pancreatitis.     

Evaluation of a rapid technique for antibody elution

This study evaluated a new rapid acid elution technique using citric acid. This technique was compared to the commonly used digitonin acid procedure. Twenty patient or donor antibodies with specificities in the Rhesus, Kell, Kidd, or Duffy systems were used to coat red cells. Eluates produced from these cells by the citric acid procedure were equivalent or greater in volume and potency to those produced by a digitonin acid method. The citric acid procedure required five to nine minutes to complete, while the digitonin acid procedure required 28 to 44 minutes. The citric acid technique is a rapid means of producing a potent eluate.     

The diagnostic value of hepatocyte paraffin antibody 1 in differentiating hepatocellular neoplasms from nonhepatic tumors: a review

Hepatocyte paraffin-1 (HepPar-1) is a recently developed monoclonal antibody that appears to identify an antigen unique to hepatocellular mitochondria. This article reviews the use of this new antibody in the differential diagnosis of primary hepatocellular neoplasms, cholangiocarcinomas, and carcinomas metastatic to the liver. Hepatocyte paraffin-1 appears to be the most sensitive and specific positive marker of hepatocellular differentiation, but like any immunohistochemical marker, should be interpreted only in the context of the overall clinicopathologic picture and as part of a panel of antibodies.     

Molecular testing for melanocytic tumors: a practical update

The work-up of melanocytic tumors has undergone significant changes in the last years following the exponential growth of molecular assays. For the practicing pathologist it is often difficult to sort through the myriad of different tests available currently for clinical use. The molecular tests used in melanocytic pathology can be broadly divided into 4 categories: (i) Tests useful in the differential diagnosis of nevus versus melanoma (primarily used as an aid in the diagnosis of histologically ambiguous melanocytic tumors), (ii) Tests that predict prognosis in melanoma, (iii) Tests useful in the classification of melanocytic tumors and (iv) Tests that predict response to systemic therapy in melanoma. This review will present an updated overview of major ancillary tests used in clinical practice.     

The desmoplastic melanocytic naevus: a distinct histological entity

Fifteen cases of desmoplastic melanocytic naevi are described in 12 female and three male patients, ranging in age from 8 to 83 years. The commonest site for the lesions was the upper limb. The lesions were characterized by a dense sclerotic or desmoplastic appearance of the dermal collagen surrounding a population of predominantly epithelioid naevus cells, some of which had a bizarre but non-malignant cytology. The cause of the stromal change is not established. We suggest that these lesions constitute a discrete entity which should be described in standard textbooks of dermatopathology.     

Asymmetry in melanocytic lesions: a morphometric analysis.

The purpose of this study was to establish a morphometric technique that would approximate the subjective histological criteria of asymmetry in the diagnosis of malignant melanoma. The dermal and epidermal outlines of 52 consecutive malignant melanomas and 56 consecutive melanocytic nevi were digitized and analyzed for morphometric parameters of size, coordinates, and shape. The two parameters that showed the most significant discriminatory functions were the differences in the center of masses of the epidermal and dermal components in the horizontal dimension and the length of the longest segment in the lesion.     

Evaluation of anaerobic flora in lung neoplasms

Purpose of this study was to analyse the kind and frequency of anaerobic bacteria in the lower respiratory tract as well as susceptibility of the bacteria to antibiotics. Material from 35 patients with lung tumour derived from tumour and post-tumoural area sample. Collected sample was cultivated in anaerobic and aerobic conditions. Anaerobic bacteria were found in 23 (66%) samples. Totally there were 44 isolated of anaerobic bacteria strains. The most common G-negative strains belonged to genus of Bacteroides (11 strains); two types dominated: Bacteroides gracilis (4 strains) Bacteroides fragilis (4 strains). Among G-positive anaerobic bacteria most common were Peptostreptococcus (9 strains). G-positive rods were represented by Propionibacterium genus (8 strains). The susceptibility of anaerobic bacteria was estimated towards mostly used antibacterial drugs. Results suggest that most of bacteria were susceptible for imipenem, piperacillin/tazobactam, amoxicillin/clavulanate, ampicillin/sulbactam, metronidazole, piperacillin and clindamycin. Bacteria were less susceptible to roxitromycin and examined cephalosporins. Most of the strains were resistant for cefuroxime.     

Deep penetrating nevus: a distinct variant of melanocytic nevus

Deep penetrating nevus (DPN) is a variant of melanocytic nevus which goes unrecognized due to its relative rarity and may be misinterpreted as malignant melanoma. It commonly presents in young adults as a dark pigmented lesion on the face, neck, or shoulder. A 60-year-old lady presented with a mole over the left arm of 8 years duration. A biopsy of the lesion was performed under the clinical impression of a compound nevus with suspicion of malignancy. Based on the histologic features, a diagnosis of DPN was put forward.     

膝关节置换后注射含类固醇鸡尾酒治疗安全性的荟萃分析

背景:类固醇具有强大的抗炎、止吐及镇痛作用而被广泛用于围术期镇痛,有研究表明膝关节置换后膝关节周围注射含类固醇的鸡尾酒镇痛疗法可缓解术后疼痛、改善膝关节活动度及减少相关并发症,但也有研究认为类固醇可增加术后感染、髌腱断裂等风险。因此膝关节周围注射含类固醇鸡尾酒疗法在膝关节置换后镇痛中的安全性和疗效尚存在争议。目的:通过荟萃分析系统评价膝关节置换后运用含类固醇鸡尾酒疗法镇痛的疗效和安全性。方法:检索PubMed/Medline、Cochrane Central Register of Controlled Trials、EMBASE数据库2019年4月前的文献,收集所有膝关节置换后局部运用类固醇镇痛的随机对照试验,筛选出符合条件的文献。由2名研究者分别单独使用Cochrane 5.0风险偏倚评估工具对文献方法学偏倚进行评价,提取文献数据并用Review Manager 5.2软件进行荟萃分析。结果与结论:①共纳入10篇随机对照试验,820例患者;②Meta分析显示:类固醇组术后第1天的目测类比评分低于对照组[MD=-1.52,95%CI(-2.94,-0.10),P=0.04],术后第1,2,3,4,5天的关节活动度高于对照组[MD=11.57,95%CI(9.85,13.30),P<0.000 01;MD=9.03,95%CI(6.67,11.38),P<0.000 01:MD=5.73,95%CI(0.85,10.60),P=0.02:MD=5.53,95%CI(0.68.10.38),P=0.03;MD=5.90.95%CI(0.87.10.93),P=0.02],吗啡使用量少于对照组[MD=-7.94,95%CI(-14.35,-1.53),P=0.02],住院时间短于对照组[MD=-0.98,95%CI(-1.25,-0.71),P<0.000 01],直腿抬高所需时间短于对照组[MD=0.65,95%CI(-0.86,0.44),P<0.000 01],术后C-反应蛋白水平低于对照组[WMD=-4.82,95%CI(7.41,2.23),P=0.000 3];两组膝关节KSS评分、并发症发生率比较差异无显著意义;③结果表明,膝关节置换后关节周围运用含类固醇的鸡尾酒疗法安全有效。