Extranuchal nuchal fibroma

Identification of candidate biomarkers correlated with pathogenesis of postoperative peritoneal adhesion by using microarray analysis

BACKGROUND

Postoperative peritoneal adhesion (PPA), characterized by abdominal pain, female infertility, and even bowel obstruction after surgery, has always been a major concern. The occurrence and formation of adhesion are from complex biological processes. However, the molecular mechanisms underlying the basis of microarray data profile, followed by peritoneal adhesion formation, are largely unknown.

AIM

To reveal the underlying pathogenesis of PPA at the molecular level.

METHODS

The gene expression profile was retrieved from the Gene Expression Omnibus database for our analysis. We identified a panel of key genes and related pathways involved in adhesion formation using bioinformatics analysis methods. We performed quantitative PCR and western blotting in vivo to validate the results preliminarily.

RESULTS

In total, 446 expressed genes were altered in peritoneal adhesion. We found that several hub genes (e.g., tumor necrosis factor, interleukin 1 beta, interleukin 6, C-X-C motif chemokine ligand 1, C-X-C motif chemokine ligand 2) were marked as significant biomarkers. Functional analysis suggested that these genes were enriched in the Toll-like receptor signaling pathway. According to the Kyoto Encyclopedia of Genes and Genomes pathway and published studies, TLR4, myeloid differentiation primary response protein 88 (MyD88), and nuclear factor kappa B (NF-κB) played essential roles in Toll-like signaling transduction. Here, we obtained a regulatory evidence chain of TLR4/MyD88/NF-κB/inflammatory cytokines/peritoneal adhesion involved in the pathogenesis of postoperative adhesion. The results of the microarray analysis were verified by the animal experiments. These findings may extend our understanding of the molecular mechanisms of PPA.

CONCLUSION

The regulatory evidence chain of TLR4/MyD88/NF-κB/inflammatory cytokines/peritoneal adhesion may play key roles in the pathogenesis of PPA. Future studies are required to validate our findings.

Extra nuchal-type fibroma associated with elastosis, traumatic neuroma, a rare APC gene missense mutation, and a very rare MUTYH gene polymorphism: a case report and review of the literature*

We report a case of an extra nuchal-type fibroma in a 51-year-old male suspected to have attenuated familial adenomatous polyposis (Gardner's syndrome), who presented with a longstanding buttock mass excised due to enlargement and pain. Histopathologically, lobules of haphazard, hypocellular, hyalinized collagen bundles replaced the dermis and subcutis and entrapped nerve bundles, mimicking Morton neuroma. Ramifying nerve twigs found around larger nerve fascicles showed the co-existence of traumatic neuroma. Elastic tissue stain revealed elastosis characterized by large, arborizing fibers lying between and within the hyalinized collagen bundles. Modified Masson's trichrome stain showed light blue staining of collagen bundles producing the hyalinized nodules with irregular, light red staining of collagen bundles at their periphery and within tumor collagen. Compression and/or degeneration of collagen and secondary elastosis with later entrapment by tumor collagen could explain this microscopic phenotype. By immunohistochemistry, tumor spindle cells expressed nuclear β-catenin and cyclin D1, mostly within regions of fibrosis implicating activation of the adenomatous polyposis coli (APC)-Wnt pathway. Genetic analysis showed a missense mutation in APC gene (c.7504G>A, p.G2502S in exon 15) and a functional homozygous polymorphism in the MUTYH gene (c.36+325G>C, (IVS1+5G/C)). Nuchal-type fibroma has been associated with Gardner's syndrome and trauma. In this patient, genetic predisposition coupled with repetitive, localized trauma and collagen degeneration may have provided the stimulus for the development of extra nuchal-type fibroma.

Nuchal-type fibroma of the ankle: a case report

Nuchal-type fibroma is rare benign fibrous tumor that has the potential to recur. It is typically located in the subcutaneous tissues of the posterior aspect of the neck, although it can affect other anatomical sites. Extranuchal involvement occurs most commonly in the back, shoulder, and face, as well as other sites specified in single case reports. In this report, we describe the case of a patient presenting with a nuchal-type fibroma arising in the ankle. The lesion infiltrated the superior extensor retinaculum. Marginal resection was performed, and there was no evidence of recurrence after 12 months of follow-up. To our knowledge, this is the first report of a nuchal-type fibroma localized to the ankle.

Nuchal-type Fibroma of the Coccyx

Nuchal-type fibroma is a recently described, rare, tumor-like process of fibrous tissue occurring chiefly in the dorsocervical area. Nuchal-type fibromas in extranuchal locations are morphologically indistinguishable from lesions involving the nuchal region. Histopathologic findings of nuchal-type fibroma are poorly demarcated, dense collagen bundles with sparsely scattered fibroblasts, some interspersed adipose tissue, and entrapped nerve fibers. We report a patient with a mass on the coccyx area, and these were histopathologically consistent with nuchal-type fibroma. This tumor was surgically excised, and no recurrence had been noted during the two year follow-up period.

Collagen-rich tumors of soft tissues: an overview

Although relatively common, soft tissue tumors frequently present diagnostic problems for practicing pathologists. Immunohistochemistry has facilitated the diagnosis of many mesenchymal tumors; however, there is considerable overlap in the staining profiles among cells demonstrating fibroblastic and myofibroblastic differentiation. It has been our experience that soft tissue tumors associated with abundant extracellular collagen deposition commonly cause problems in classification. One reason for this is that tumors displaying this morphology include representatives from different histogenetic families. Specifically, tumors exhibiting fibroblastic, myofibroblastic and even lipomatous differentiation may manifest as a densely collagenous mass. It is the purpose of this review to highlight these collagen-rich soft tissue tumors.

Gardner-associated fibromas (GAF) in young patients: a distinct fibrous lesion that identifies unsuspected Gardner syndrome and risk for fibromatosis

Gardner syndrome (GS), caused by mutations in the adenomatous polyposis coli (APC) gene, is characterized by polyposis coli, osteomas, and various soft-tissue tumors. If undetected or untreated, virtually all patients develop colonic carcinoma at a young age. Early detection, while essential, can be difficult because of attenuated phenotypes or spontaneous mutations. We present the clinicopathologic features of 11 identical fibromatous lesions that we have termed Gardner-associated fibroma (GAF), which not only appear to be a part of the spectrum of lesions associated with GS but, in some cases, represent the sentinel event leading to its detection. The GAFs occurred in 11 patients (5 boys and 6 girls; age range, 3 months-14 years), were solitary (n = 7) or multiple (n = 4), and occurred in the superficial and deep soft tissues of the paraspinal region (n = 7), back (n = 3), face (n = 2), scalp (n = 2), chest wall (n = 2), thigh (n = 1), neck (n = 1), and flank (n = 1). Histologically, GAFs resemble nuchal-type fibromas (NFs), consisting of thick, haphazardly arranged collagen bundles between which are found occasional bland fibroblasts, and having margins that frequently engulf surrounding structures including adjacent fat, muscle and nerves. After surgical excision, four patients developed recurrences that were classic desmoid fibromatoses (DFs). In one patient with multiple GAFs, one lesion had the features of GAF and DF in the absence of surgical trauma. A family history of GS or polyposis (n = 6) or DF (n = 1) was known at the time of surgery in seven patients. In three patients, the diagnosis of GAF resulted in the diagnosis of unsuspected APC in older family members, with the detection of an occult colonic adenocarcinoma in one parent. In the family of the remaining patient, no stigmata of GS were present. Genetic analysis of this child was performed to investigate the presence of a spontaneous (new) mutation; however, no abnormalities were detected. The significance of GAF is that it serves as a sentinel event for identifying GS kindreds, including those with a high risk for the development of DF, and it may potentially identify children with spontaneous mutations of the APC gene. Because NFs and GAFs resemble one another, we suggest that a subset of NF occurring in multiple sites, unusual locations, or children may be GAF.

Nuchal-type fibroma in two related patients with Gardner's syndrome

Nuchal-type fibroma is a distinct subcutaneous and dermal fibrous tissue proliferation that has been previously definitely identified in one patient with Gardner's syndrome and has been possibly present in two others. Gardner's syndrome is an autosomal-dominant condition with variable expressivity that comprises epidermoid cysts, fibrous tumors, osteomas, intestinal polyposis, as well as other findings. We report two cases of nuchal-type fibroma presenting in a 13-year-old boy in the right upper back and in his 60-year-old grandfather in the upper chest at the posterior axillary line. Both individuals carried a diagnosis of Gardner's syndrome and neither of them had diabetes. Although the boy has as of now only presented with cutaneous manifestations of Gardner's syndrome, his grandfather has exhibited both cutaneous and intestinal evidence of this syndrome. In addition, the boy's mother and her sister have documented Gardner's syndrome. Light microscopic findings of nuchal-type fibroma from both patients include paucicellular, haphazardly arranged collagen bundles with entrapped adipose tissue. A marked diminution of elastic fibers was noted with Van-Gieson stains. The lesions were diffusely positive for CD34 and contained a few factor XIIIa-positive cells. Electron microscopic analysis revealed no differences between the collagen comprising the nuchal-type fibroma as compared with control dermal collagen obtained from skin away from the tumor. These cases strengthen the view that there is an association between nuchal-type fibroma and Gardner's syndrome.

Nuchal fibroma associated with scleredema, diabetes mellitus and organic solvent exposure

A case of scleredema diabeticorum of Buschke associated with nuchal fibroma and organic solvent exposure is reported. The patient presented with a neck mass causing discomfort and restriction of movement. Histological examination showed this to be a nuchal fibroma. Additionally, there was widespread induration of the skin of his trunk which was asymptomatic. A biopsy showed features of scleredema. This is the first reported association of these two conditions, both of which show increased and thickened collagen bundles without significant fibroblast proliferation. They differ by the occurrence of mucin in scleredema, although this is not always demonstrable, particularly in late lesions. The possibility that nuchal fibroma is an end stage, localized form of scleredema is canvassed. The patient's medical history included insulin-dependent diabetes mellitus with complications of retinal vessel thrombosis and peripheral neuropathy. The patient also had significant past exposure to a wide variety of chemicals, including organic solvents.

Nuchal fibroma: a clinicopathological review

Nuchal fibroma, or collagenosis nuchae, is a benign soft tissue tumor that arises from the posterior cervical subcutaneous tissue, with a predilection for the interscapular and paraspinal regions. Because of its benign clinical course and its close histopathologic similarity to other benign head and neck lesions, this lesion may be misdiagnosed and underreported. The purpose of this paper is to review the histopathologic and radiologic findings unique to nuchal fibroma, and compare and contrast it to the other soft tissue neoplasms within the clinical differential diagnosis. These include several benign (elastofibroma, lipoma, fibrolipoma, nodular fasciitis) and rare malignant entities (fibrosarcoma, liposarcoma, fibromatosis).

Nuchal-type fibroma: a clinicopathologic study of 52 cases

BACKGROUND

Nuchal-type fibroma (NTF) usually arises in the posterior aspect of the neck. Previously published reports describe only 11 cases and provide limited clinicopathologic information.

METHODS

Fifty-two examples of NTF from 50 patients were analyzed from the files of the Soft Tissue Registries of the Armed Forces Institute of Pathology in Washington, DC, and the Faculty Hospital in Pilsen, Czech Republic.

RESULTS

The age of the patients ranged from 3 to 74 years (mean, 40 years). There were 41 males and 9 females. Thirty-six NTFs were located in the posterior neck region and 16 were from extranuchal sites. Two patients had had lesions excised from both a nuchal and an extranuchal location. The mean greatest tumor dimension was 3.2 cm. Microscopically, all examples had a superficial (subcutaneous and sometimes dermal) component and consisted of paucicellular, thick bundles of lobulated collagen fibers with inconspicuous fibroblasts. Entrapped adipose tissue and traumatic neuromalike nerve proliferations were typically present. Skeletal muscle infiltration was also seen in a minority of cases. Eleven of 25 patients (44%) for whom clinical information was available reportedly had diabetes. Gardner's syndrome was documented in one patient and was possibly present in two additional individuals. During follow-up, five patients had local recurrences, but none of the recurrences were destructive and all were ultimately controlled by local reexcision.

CONCLUSIONS

NTF is a rare, tumorlike accumulation of collagen that often affects the posterior neck region but can also occur in a number of other sites. The process has a strong association with diabetes and also appears to be linked to Gardner's syndrome. Local recurrence probably reflects the persistence of local or systemic factors related to its pathogenesis.