Incidental Melanocytic Nevi in Hemorrhoidectomy Specimens.

BACKGROUND: Benign melanocytic nevi (MN) of the anal canal are exceptional and require adequate differential diagnosis. There are no data on incidence of these lesions. Only a single case report of hemorrhoid with an MN has been reported. The necessity of routine pathologic evaluation of hemorrhoidectomy specimens has been questioned. MATERIAL AND METHODS: The authors undertook a retrospective histologic study of the hemorrhoidal tissue obtained in a series of 1918 consecutive hemorrhoidectomies performed between January 2004 and November 2012. RESULTS: Incidental hemorrhoidal MN were detected in 4 (0.21%) patients. The ratio observed was 1 nevus in 480 specimens. Lesions were intradermal or purely junctional in nature. There were no mitoses or architectural disorder. An intradermal nevus showed localized pagetoid melanocytes. The mean age of the patients was 56.5 years (range 47-73 years). The mean size of nevi was 5.86 mm (range 1.89-13.86 mm). All cases were present in external hemorrhoids. CONCLUSIONS: Although uncommonly, incidental MN can be observed in hemorrhoidal tissue. They may show features of flexural nevi and pagetoid melanocytes. Routine histopathological study of hemorrhoidectomy specimens would help to detect benign or malignant melanocytic tumors of the anal canal as these neoplasms can be easily missed clinically. Furthermore, this practice would allow early diagnosis of significant associated processes.

Subcutaneous infiltrative nodule at the injection site of low-molecular weight heparin simulating malignancy.

Low-molecular weight heparins (LMWHs) are the standard agents used for the prevention and treatment of thromboembolic disorders. Despite their widespread use, reports on adverse effects from LMWHs are uncommon. The present report describes a 23-year-old woman with a 3.8-cm solitary, fibrofatty, poorly demarcated nodule involving the subcutaneous tissue of the infraumbilical abdominal wall that appeared 4 years after iterative local administration of LMWH. Microscopically, the nodule showed atypical cells, with bizarre nuclei in the septa of cellular fibrous tissue dissecting the adipose lobules, in the absence of any other malignant changes. To the best of our knowledge, this kind of LMWH-related lesion has not been previously reported. The lesion may result from the combination of an idiosyncratic reaction to the LMWH with local trauma being a probable promoting factor. Alternatively, this reactive proliferation may be entirely due to the trauma represented by repeated injections. This rare process could easily be confused with liposarcoma. As the clinical history of injections is often not provided in the requisition form, pathologists should be aware of this adverse effect from LMWH to avoid misdiagnosis and excessive treatment.

Mucin-secreting clear cell renal cell carcinoma. A rare variant of conventional renal cell carcinoma.

We report herein one case of conventional renal cell carcinoma (RCC) producing extensive extracellular mucinous secretion in a 71-year-old man. To the best of our knowledge, the presence of mucinous secretion in this tumor has not been documented. Mucin production, despite its low frequency, can be considered an additional feature of conventional RCC. Therefore, clear cell RCC should be added to the list of parenchymal renal tumors that can show significant mucin secretion; and it should be included in the inventory of morphologic variations of this tumor, which may cause diagnostic difficulties. It is of primary importance to distinguish mucin-secreting clear cell RCC from the metastasis of a mucin-secreting tumor to conventional RCC. Presence of mucin in a clear cell carcinoma does not exclude a renal origin.

Nodular spindle cell proliferation in the wall of a varicose vein mimicking Kaposi's sarcoma.

Exuberant reparative reactions resembling sarcoma have been reported in the genitourinary tract, thyroid, breast, lymph node, oral cavity and skin, but not in a varicose vein. Presented herein is the case of a 55-year-old man who showed an incidental nodular lesion in the wall of a varicose vein on the left leg. The nodule consisted of fascicles of spindled cells with ovoid or elongated nuclei and delicate chromatin that showed diffuse reactivity for CD31, alpha-smooth muscle actin and D2-40. This histopathological appearance, when coupled with extravasated erythrocytes and interstitial hemosiderin deposits, resembled Kaposi's sarcoma or spindle cell angiosarcoma. Key features helpful for recognizing that the proliferation we describe is a form of tissue repair include an association with obvious hemorrhage; lack of well-formed curved fascicles of spindled cells; lack of intracytoplasmic hyaline globules; lack of intracellular vacuolization; cytological blandness; low mitotic count; absence of inmmunoreactivity for human herpesvirus-8 (HHV-8) latent nuclear antigen-1; and absence of HHV-8 in polymerase chain reaction (PCR) analysis.

Hypodermal decidualized endometrioma with aberrant cytokeratin expression. A lesion mimicking malignancy.

Decidualized endometrioma is a pseudoneoplastic lesion that may appear as a solitary nodule in the hypodermis, simulate a malignant epithelioid tumor, and can represent a diagnostic challenge. A 36-year-old woman delivered a full-term baby by cesarean. At the immediate puerperium, she complained of a subcutaneous nodule measuring 2.5 cm, underneath a previous caesarean scar from the former full-term delivery 3 years earlier. Histologic features included a nodular growth pattern of large monomorphic epithelioid cells showing diffuse positivity for cytokeratin (AE1/AE3, 18), human placental lactogen, and CD10 and focal positivity for inhibin alpha. The main differential diagnoses include trophoblastic neoplasia and deciduoid mesothelioma. Good clinicopathological correlation is essential for the correct diagnosis. Immunohistochemical stains can be misleading. An important clue is the combination of large decidualized cells and lumens lined by flat or low cuboidal cells that are atrophic endometrial glands. This lesion has a benign behavior.

25-Hydroxyvitamin D and Cardiorespiratory Fitness in Prepubertal Overweight and Obese Children.

Childhood obesity has become a major global health problem. Vitamin D deficiency and poor cardiorespiratory fitness are highly prevalent in children with overweight or obesity, but little is known about their relationships. In this study, we aimed to analyze the relationship between serum 25-hydroxyvitamin D (25(OH)D) and cardiorespiratory fitness parameters in prepubertal obese and overweight children. A cross-sectional design with a sample of 57 prepubertal children, aged 9-11 years, with overweight or obesity was used. The fasting concentration of 25(OH)D was analyzed with a chemiluminescent microparticle immunoassay. Fat and lean body masses were determined by using DXA. Maximal oxygen uptake (VO2max) was measured with the maximal treadmill test. A total of 68.4% of the sample had sufficient levels of 25(OH)D. As expected, their cardiorespiratory fitness was poor compared with that of normal-weight children, but 60% of the group exceeded the median obesity-specific reference values. No differences were found between the sexes for relative VO2max or 25(OH)D levels. Moreover, no correlations were found between 25(OH)D and body composition or cardiorespiratory parameters for sex or vitamin D groups. Vitamin D status seems not to be directly related to body composition or cardiorespiratory fitness in prepubertal overweight or obese children.

Hypoxia-induced autophagy drives colorectal cancer initiation and progression by activating the PRKC/PKC-EZR (ezrin) pathway.

In solid tumors, cancer stem cells (CSCs) or tumor-initiating cells (TICs) are often found in hypoxic niches. Nevertheless, the influence of hypoxia on TICs is poorly understood. Using previously established, TIC-enrichedpatient-derived colorectal cancer (CRC) cultures, we show that hypoxia increases the self-renewal capacity of TICs while inducing proliferation arrest in their more differentiated counterpart cultures. Gene expression data revealed macroautophagy/autophagy as one of the major pathways induced by hypoxia in TICs. Interestingly, hypoxia-induced autophagy was found to induce phosphorylation of EZR (ezrin) at Thr567 residue, which could be reversed by knocking down ATG5, BNIP3, BNIP3L, or BECN1. Furthermore, we identified PRKCA/PKCα as a potential kinase involved in hypoxia-induced autophagy-mediated TIC self-renewal. Genetic targeting of autophagy or pharmacological inhibition of PRKC/PKC and EZR resulted in decreased tumor-initiating potential of TICs. In addition, we observed significantly reduced in vivo tumor initiation and growth after a stable knockdown of ATG5. Analysis of human CRC samples showed that p-EZR is often present in TICs located in the hypoxic and autophagic regions of the tumor. Altogether, our results establish the hypoxia-autophagy-PKC-EZR signaling axis as a novel regulatory mechanism of TIC self-renewal and CRC progression. Autophagy inhibition might thus represent a promising therapeutic strategy for cancer patients. ABBREVIATIONS: ATG: autophagy related; BECN1: beclin 1; BNIP3: BCL2 interacting protein 3; BNIP3L: BCL2 interacting protein 3 like; CQ: chloroquine; CSC: cancer stem cells; CRC: colorectal cancer; HIF1A/HIF-1α: hypoxia inducible factor 1 subunit alpha; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; PRKC/PKC: protein kinase C; SQSTM1/p62: sequestosome 1; TICs: tumor-initiating cells.

Clinically unapparent melanocytic nevi on the prepuce.

BACKGROUND: Melanocytic nevi from the genitalia are uncommon. Nevi on the vulva are much better described than nevi on male genitalia. To our knowledge, a systematic study of preputial melanocytic nevi has not been reported. OBJECTIVE: To investigate the frequency of clinically unapparent melanocytic nevi on a series of preputial excisions. MATERIALS AND METHODS: We undertook a prospective histologic study of the prepuce obtained in a series of 372 consecutive circumcisions for phimosis performed during the period between January 2000 and December 2002. RESULTS: Incidental preputial melanocytic nevi were detected in four (1.1%) patients. Lesions were dermal in nature, most of them showed pigment in superficial dermal nests and had pseudovascular spaces. There were no cytologic atypia, mitotic figures, architectural disorder or inflammatory infiltrate. The mean (standard deviation, SD) of the maximum diameter was 1.08 (0.85) mm (range 0.34-1.79 mm). The mean age (SD) of the patients was 41.5 (4.95) years (range 29-58). CONCLUSIONS: Incidental melanocytic nevi, although uncommonly, can be observed in the prepuce. They are detected in adults and may pose a diagnostic challenge when they are detected in the setting of concurrent malignant melanoma.

Colonial architecture and growth dynamics of Staphylococcus aureus resistant to methicillin.

The aim of the study was to explore the structure and growth dynamics of Staphylococcus aureus resistant to methicillin (MRSA) colonies using semithin sections visualized by light microscope. One S. aureus susceptible to methicillin (MSSA) and one MRSA clinical strains were studied. Colonies in agar plates were embedded in epoxy resin after each incubation period (24 h and 48 h) at 37 degrees . Semithin sections of 0.5 µm were stained with toluidine blue and visualized by light microscope. Microscopically, no structural differences were observed between SASM and SARM colonies but differences were observed in both strains between 24 and 48 h incubation periods. Colonies showed two layers clearly differentiated at 24 h independently of the resistance to methicillin: (A) one basal layer with high density of population in contact with culture media, and (B) one superficial layer with a lower density of population. Colonies showed four layers at 48 h: (A) one basal layer with high density of population; (B) one clear layer constituted by very degraded bacterial remains in which can be observed cocci dispersed with their dyeing properties; (C) one mixed layer constituted by viable bacteria and little degraded bacterial remains (D) one superficial layer with a lower density of population than basal layer. Colonial architecture is a complex and time-dependent process.

Pagetoid dyskeratosis of the nipple epidermis: an incidental finding mimicking Paget's disease of the nipple.

Pagetoid dyskeratosis (PD) is considered a selective keratinocytic response in which a small part of the normal population of pale keratinocytes is induced to proliferate. PD has been found incidentally in the squamous epithelium of the skin and mucosas in various locations, but not in the nipple. In cases in which PD cells are conspicuous, there is the danger of overdiagnosis. In a retrospective study, we describe the location and incidence of PD and other pale cells in the nipple epidermis, in 288 mastectomy specimens from women operated on for breast carcinoma, in situ or infiltrating, selected consecutively from our histopathologic files. In addition to the conventional histologic methods an immunohistochemical study was performed in selected cases. PD was found in 184 (63.9%) cases and was a prominent finding in 37 (12.8%) cases. Toker cells (TCs) were identified by standard light microscopy in 24 (8.3%) nipples. Paget carcinoma cells (PCCs) were found in 12 (4.2%) cases, and in 9 (3.1%) they were an incidental finding. The immunohistochemical profile of each type of pale cells was as follows: PD cells, EMA-,LMWCK-,CK7-,HMWCK+, CEA-, HER2/neu protein-, HMB45-, HPV-; TCs, EMA+, LMWCK+, CK7+, HMWCK-, CEA-, HER2/neu protein-, HMB45-, HPV-; PCCs, EMA+, LMWCK+, CK7+, HMWCK-, CEA+, HER2/neu protein+, HMB45-, HPV-. In conclusion, friction may be the stimulus for the appearance of PD cells. PD cells must be distinguished from TCs, PCCs, clear cells of Bowen's disease, pagetoid melanoma cells, cells of clear cell papulosis, koilocytes, artifactual clear cells, and glycogen-rich squamous cells. A combination of immunohistochemical markers is useful for this distinction; however, routine histologic study is usually adequate for recognizing PD. Pathologists should be familiar with the histologic features of PD in the nipple epidermis to avoid misdiagnosis.

The UOK 257 cell line: a novel model for studies of the human Birt-Hogg-Dubé gene pathway.

The establishment, characterization, and tumorigenicity of a new epithelial cell line (UOK 257) derived from human renal carcinoma of an individual with Birt-Hogg-Dubé (BHD) syndrome are reported. Unlike other established renal tumor cell lines from sporadic renal cell carcinoma, this is the first established renal tumor cell line of BHD, an inheritable neoplastic syndrome. The isolated tumor cells display loss of contact inhibition in vitro, and produce subcutaneous tumors in mouse xenografts. Histopathologic, ultrastructural, and cytogenetic characterizations of the established tumor cells are reported. Cytogenetic analysis using spectral karyotyping on UOK 257 cells revealed 17p loss and a near-triploid and aneuploid karyotype with multiple fluorescence in situ hybridization analysis using a locus-specific gene probe for MYC. The result demonstrates that the established tumor cells consist of two cell populations, one containing four and one containing five copies of the MYC oncogene.

Postoperative spindle cell nodule of the breast: Pseudosarcomatous myofibroblastic proliferation following endo-surgery.

Despite the frequent use of fine-needle aspiration, core biopsy and surgery, postoperative spindle cell nodule (PSCN) is a rare pathological complication that may be diagnostically treacherous. Presented herein is the case of a 52-year-old woman who developed a 7 mm mammary nodular lesion 66 days after removal of an area of columnar cell hyperplasia involving cellular and architectural atypia, performed with the Mammotome Breast Biopsy System. The lesion was highly cellular and composed of intersecting fascicles of plump spindle cells with blunt-ended elongated nuclei and nucleoli easily visible. Interspersed mononuclear cells and hemosiderin-laden macrophages were evident. PSCN is a reactive, benign myofibroblastic proliferation. Differential diagnosis includes benign and malignant spindle cell lesions of the breast. Recognition of this reactive lesion will avoid overdiagnosis of spindle cell malignant tumor. Attention to clinicopathological and histological features should result in accurate recognition of this lesion.

Apocrine hidrocystoma of the foreskin. A case report and review of the literature.

Apocrine hidrocystoma (AH) is an uncommon benign cystic tumor that is rarely located in the genitalia. We present the case of a 52-year-old uncircumcised man who presented an AH on his foreskin. The lesion was non-proliferative. Including the present report, only 10 cases of penile AH have been published to date. Most patients are adult (mean age 39.2 years, range 25-56 years) and only one case in one child and another case in one adolescent have been reported. The lesion involves more commonly the foreskin followed by the shaft. The average maximum diameter was 1.6 cm (range 0.3-3 cm). The majority (70%) of tumors are unilocular. The main differential diagnosis of AH includes eccrine hidrocystoma, epidermal inclusion cyst and male median raphe cyst. Complete excision of the lesion is curative.

Ectopic epididymal tissue in appendix testis.

Aberrant epididymal tissue is uncommon and may be associated with an undescended testis. To the best of our knowledge, aberrant epididymal tissue has not been described in a testicular appendix. We report the case of a 7-year-old boy with left cryptorchidism who underwent a homolateral orchidopexy. At operation, the surgeon removed a pedunculated appendix testis containing an epididymal heterotopia. This Wolffian-derivative tissue was confirmed by the diffuse strong CD10 reactivity of the luminal border of the epithelial cells. Awareness of this aberrant tissue avoids misinterpretation as a transected functional reproductive structure.

Isolated (localized) idiopathic granulomatous (giant cell) vasculitis in an intramuscular lipoma.

Isolated (localized) idiopathic granulomatous vasculitis (IGV) is an uncommon, heterogeneous, and poorly defined group of disorders characterized by infiltration of the arterial wall caused by compactly grouped mononuclear phagocytes, with or without giant cells, in segmental distribution. We report on a 55-year-old woman with IGV limited to an intramuscular lipoma of the left thigh. The vasculitis was identified incidentally upon microscopic examination of the removed tumor. The IGV was centered on two medium-sized arteries, accompanied by narrowing of the lumens, and not associated with secondary changes such as infart or postinfart fibrosis. The inflammatory infiltrate was rich in T-lymphocytes and macrophages, with the presence of giant cells. The patient was asymptomatic and well in a follow-up period of 2 months, during which she was not treated. To our knowledge, this is the first report of lipoma involvement in localized IGV. It is important to distinguish cases of isolated intratumorous IGV from systemic disease, because the latter implies a poor prognosis and requires an aggressive treatment.

Viability of Pathologic Cartilage Fragments as a Source for Autologous Chondrocyte Cultures.

OBJECTIVE: To study if a culture of chondrocytes can be obtained from pathologic hyaline cartilage (PHC) fragments. DESIGN: Twenty-five men and 9 women with osteochondritis dissecans (OCD) in 11 cases, arthrosis in 13 patients, and trauma in the remaining 10 cases were included. The PHC fragments and a small sample of the next healthy cartilage were extracted by arthroscopy. According to the appearance, the PHC samples were divided into fixed (3 cases), flapped (6 patients), or loose bodies (25 cases), depending on the attachment degree of the cartilage to the subchondral bone. Approximately half of each pathologic sample and the whole healthy one were digested to isolate the cells trying to establish the cell culture. RESULTS: We were able to establish a cell culture in 7 out of 34 (20.6%) PHC samples (positive samples), whereas in the remaining 27 (79.4%) no cell growth was observed (negative samples). Most of the negative samples were loose bodies (P = 0.005) taken from patients with OCD or arthrosis (P = 0.001) with an evolution time of more than 1 year (P < 0.001). The best binary logistic regression model (P < 0.001) showed that the only factor affecting the establishment of cell culture was the evolution time (P = 0.044). CONCLUSION: It is possible to culture chondrocytes from osteochondral fragments if they are traumatic, within a year of injury and not from fragments due to arthrosis or OCD.

Incidental detection of an asymptomatic papillary fibroelastoma on a control biopsy of a heart transplant recipient.

BACKGROUND: Papillary fibroelastoma (PFE) of the right ventricle is a rare lesion. This tumor has not been described in the heart of a cardiac transplant recipient. METHODS AND RESULTS: We report a 42-year-old woman suffering from chronic ischemic cardiopathy who underwent an orthotopic cardiac transplantation. Five years after surgery, the control two-dimensional echocardiography showed no abnormalities. At this time, the programmed endomyocardial biopsies of the right ventricle included a 2-mm lesion that was diagnosed as PFE. To our knowledge, only a previous case of this tumor has been detected at random in a control cardiac biopsy. Differential diagnosis includes chordae tendinae removed at the time of cardiac sampling, Lambl excrescence, and myxoma. CONCLUSION: PFE can arise in a cardiac transplant recipient and may be detected on a random programmed biopsy.

Intraoral tumor with rapid growing. Report of a case.

The appearance of an intraoral mass is common in our specialty. Most are benign lesions, but some are primary malignancies. Metastases account for less than 1% of all oral malignancies. An 86 year old woman was referred to our department with a large, asymptomatic, intraoral, fast-growing mass. She had no previous cancer history or other relevant physical findings. The radiology studies showed underlying bone erosion. The histological study showed a metastatic adenocarcinoma with a suspected origin in the abdomen. We were unable to identify it by non invasive diagnostic procedures. Given the patient's general status and despite the ominous prognosis of such lesions, we decided not to perform any aggressive therapy beyond removing the oral mass, in order to maintain her quality of life. There have been no local recurrences until this time.