Granular cell tumour (Abrikossoff's tumour): Case series

This case series describes three unreported cases of an uncommon benign neoplasm named Abrikossoff's tumour or granular cell tumour (GCT). This mesenchymal neoplasm apparently arises from neural or Schwann cell origin with benign and malignant forms. All cases presented here were unique nodules on oral mucosa, coming out from the connective tissue, and occurring in women with age ranging from 30 to 42 years. The histological aspects of the GCT showed large granular cells arranged in groups and nests of connective tissue separating pseudoepitheliomatous overlying surface. This feature can possibly be misunderstood with squamous cell carcinoma. The differentiation between malignant and benign GCT is evaluated by the presence of metastases which is considered the only reliable criterion for malignancy. © 2005 Elsevier Ltd. All rights reserved.

Análise mutacional da região dos exons 5 a 8 do gene supressor de tumor p53 em neoplasias mamárias caninas

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Synchronous Ossifying Fibromas of Maxilla and Mandible

Ossifying fibroma is a benign neoplasm composed of fibrocellular tissue and mineralized material of varying appearance, which is most commonly seen in the posterior region of the mandible as a solitary lesion. We report an unusual case of synchronous ossifying fibroma of maxilla and mandible. To the best of our knowledge, only 13 similar cases have been previously reported.

Calvarial ectopic meningothelial meningioma

Meningiomas are the most common benign neoplasm of the brain whereas ectopic presentation, although reported, is rare. Among these ectopic tumors, there are a group of purely intraosseous meningiomas, which usually are diagnosed differentially from common primary osseous tumor such as fibrous dysplasia and osteoid osteoma. We report a 62-year-old female with a history of headaches and 6 months of progressive right parietal bulging, with no neurological signs. Parietal craniotomy was performed with immediate titanium cranioplasty of the parietal convexity. Histopathology exams revealed an ectopic intradiploic meningioma without invasion of cortical layers, with positive staining for progesterone receptors and epithelial membrane antigen. Ectopic intraosseous meningiomas remain a rare neoplasm with only a few cases reported. The main theories to justify the unusual topography appear to be embryological remains of neuroectodermal tissue or cellular dedifferentiation. Surgical treatment seems the best curative option.

Giant cell bone lesions in the craniofacial region: a diagnostic and therapeutic challenge

Background: Giant cell tumors of bone (GCTs) are common in the long bones, but rare in the craniofacial region, with only 1% of cases occurring in the latter. Clinical, radiological, and anatomical diagnosis of this locally aggressive disease, which occurs in response to trauma or neoplastic transformation, poses a major challenge in clinical practice. Methods: The present study describes a series of 4 cases and highlights the main features of the differential diagnosis and treatment of these lesions: GCT, giant cell reparative granuloma (GCRG), and the brown tumor of hyperparathyroidism. Results: GCT presents as a benign neoplasm, most typically affecting the knees, and rarely in the temporal and sphenoid bones. It is radiologically indistinguishable from GCRG due to its lytic, poorly defined appearance. The distinction can only be made microscopically, as the presence of multinucleated giant cells scattered throughout the stroma and the absence of a history of trauma favor a diagnosis of GCT. The brown tumor of hyperparathyroidism occurs with rapid, localized osteoclast activity secondary to the effects of increased parathyroid hormone (PTH) levels; parathyroid examination is indispensable. Conclusion: The diagnosis and treatment of these lesions poses a major challenge due to their similar clinical presentation and radiological appearance. Accurate diagnosis is essential for definition of appropriate management, as complete resection is the goal in GCT and GCRG to avoid recurrence, whereas the brown tumor often yields to treatment of the underlying hyperparathyroidism.

Diagnostic utility of immunohistochemistry in distinguishing trichoepithelioma and basal cell carcinoma: evaluation using tissue microarray samples

Trichoepithelioma is a benign neoplasm that shares both clinical and histological features with basal cell carcinoma. It is important to distinguish these neoplasms because they require different clinical behavior and therapeutic planning. Many studies have addressed the use of immunohistochemistry to improve the differential diagnosis of these tumors. These studies present conflicting results when addressing the same markers, probably owing to the small number of basaloid tumors that comprised their studies, which generally did not exceed 50 cases. We built a tissue microarray with 162 trichoepithelioma and 328 basal cell carcinoma biopsies and tested a panel of immune markers composed of CD34, CD10, epithelial membrane antigen, Bcl-2, cytokeratins 15 and 20 and D2-40. The results were analyzed using multiple linear and logistic regression models. This analysis revealed a model that could differentiate trichoepithelioma from basal cell carcinoma in 36% of the cases. The panel of immunohistochemical markers required to differentiate between these tumors was composed of CD10, cytokeratin 15, cytokeratin 20 and D2-40. The results obtained in this work were generated from a large number of biopsies and resulted in the confirmation of overlapping epithelial and stromal immunohistochemical profiles from these basaloid tumors. The results also corroborate the point of view that trichoepithelioma and basal cell carcinoma tumors represent two different points in the differentiation of a single cell type. Despite the use of panels of immune markers, histopathological criteria associated with clinical data certainly remain the best guideline for the differential diagnosis of trichoepithelioma and basal cell carcinoma. Modern Pathology (2012) 25, 1345-1353; doi: 10.1038/modpathol.2012.96; published online 8 June 2012

Multicentric osteolytic lesion of the middle finger of the hand. Case report

Giant cell-rich osteolytic lesions may have overlapping clinical, radiologic, and histopathologic features, with an important degree of difficulty of diagnosis and treatment. We report a case of double osteolytic lesion at the middle-finger in a young man without previous history of hand trauma. He underwent en-bloc resection of the bone lesions and reconstruction by graft of hydroxyapatite, resulting in a good morpho-functional result. Histological diagnosis was giant cell reparative granuloma (GCRG), although several features were considered atypical, including the appearance of the giant cells and the areas of the stroma that more closely resembled a giant cell tumor. GCRG is a benign rare intraosseous lesion and the true nature is controversial and unknown. The theories are that it could be a reactive lesion, a developmental anomaly or a benign neoplasm. It appears as an osteolytic lesion that must be considered in the differential diagnosis of other “critical” bone lesions similar in clinical, as well as radiologic and pathological appearance. Further characterization studies are helpful and necessary for the proper management.

Giant cell tumor of tendon sheath: study of 64 cases and review of literature

The giant cell tumor of tendon sheath (GCTTS) is the most common benign neoplasm in the hand after the ganglion cyst. Several hypotheses were formulated about the etiological factors of these tumors, but still there is not a common opinion on etiology, prognostic factors and recurrence rate. This article presents a review of literature of the last 15 years about GCTTS to assess the demographic, clinical and histological profile. We compared the information obtained from literature with our experience of 64 cases between 2000 and 2012. Our study showed similar results to those reported in literature, except for the recurrence rate: only 3 cases (4.7%) of 64 patients reported recurrence (versus about 15% on average in literature). Among the various possible factors that predispose to recurrence, it is necessary that the surgeon ensures complete excision of the tumor and removal of any residual satellite nodules. Although the marginal excision is the treatment of choice, it is often difficult to perform due to for the location and the strict adherence of the tumor to the tendon or neurovascular bundles. We used in all cases a magnifying loupe to help a careful research of satellite lesions and to respect surrounding structures.

Sialadenoma Papilliferum with Inverted Pattern in a Young Patient: A Case Report

BACKGROUND: Sialadenoma papilliferum (SP) is a rare, benign neoplasm of salivary gland origin which manifests as an exophytic papillary excrescence of the mucosa. Indeed, SP is both an exophytic proliferation of papillary stratified squamous epithelium above the mucosal surface and an endophytic salivary ductal proliferation beneath the mucosa. It arises predominantly in minor salivary glands and usually affects patients in the age range of 32-87 years, with reports in young patients being exceedingly rare.

Spindle cell lipoma occurring in the buccal mucosa: an unusual location of this benign lipomatous neoplasm

Spindle cell lipoma is a benign lipomatous neoplasm, which rarely occurs in the oral cavity. The aims of this paper are to report a case of spindle cell lipoma located in buccal mucosa and discuss the main clinical, histological, and immunohistochemical findings of this entity. Thus, we report a 4-year history of an asymptomatic smooth surface nodule in an elderly Caucasian man with clinical hypothesis of fibroma. The histopathological examination showed spindle cells, mature adipose tissue, and many mast cells in a stroma of connective tissue presenting ropey collagen fibers bundles. After immunohistochemical analysis, the final diagnosis was spindle cell lipoma.

Myoepithelioma of the cerebellopontine angle: a previously not documented benign salivary gland-type neoplasm within the cranium

Myoepithelioma is a dimorphic neoplasm with contractile-epithelial phenotype, originally interpreted as deriving from, but not actually restricted to the salivary glands. As a novel addition to the list of exquisitely rare intracranial salivary gland-type tumors and tumor-like lesions, we report on an example of myoepithelioma encountered in the left cerebellopontine angle of a 32-year-old male. Clinically presenting with ataxia and dizziness, this extraaxial mass of 4 × 3.5 × 3 cm was surgically resected, and the patient is alive 6 years postoperatively. Histologically, the tumor exhibited a continuum ranging from compact fascicles of spindle cells to epithelial nests and trabeculae partitioned by hyalinized septa, while lacking tubular differentiation. Regardless of architectural variations, there was robust immunoexpression of S100 protein, smooth muscle actin, GFAP, cytokeratin, and vimentin. Cytologic atypia tended to be modest throughout, and the MIB1 labeling index averaged less than 1%. Fluorescent in situ hybridization indicated no rearrangement of the EWSR1 locus. We interpret these results to suggest that myoepithelioma of the posterior fossa - along with related salivary epithelial tumors in this ostensibly incongruous locale - may possibly represent analogous neoplasms to their orthotopic counterparts, ones arising within aberrant salivary anlagen. The presence of the latter lends itself to being mechanistically accounted for by either postulating placodal remnants in the wake of branchial arch development, or linking them to exocrine glandular nests within endodermal cysts. Alternatively, myoepithelioma at this site could be regarded as a non tissue-specific lesion similar to its relatives ubiquitously occurring in the soft parts.

A critical analysis of Doppler velocimetry in the differential diagnosis of malignant and benign ovarian masses

Objectives: To evaluate the intratumoral reliability of color Doppler parameters and the contribution of Doppler sonography to the gray-scale differential diagnosis of ovarian masses. Methods: An observational study was performed including 67 patients, 15 (22.4%) with malignant ovarian neoplasm and 52 (77.6%) with benign ovarian diseases. We performed the Doppler evaluation in two distinct vessels selected after decreasing the Doppler gain to sample only vessels with higher velocity flow. Doppler measurements were obtained from each identified vessel, and resistive index (RI), pulsatility index (PI), peak systolic velocity (PSV), and end-diastolic velocity (EDV) were measured. Intraclass coefficient of correlation (ICC), sensitivity, specificity, and potential improvement in gray-scale ultrasound performance were calculated. Results: The general ICC were 0.60 (95% CI 0.42- 0.73) for RI, 0.65 (95% CI 0.49- 0.77) for PI, 0.07 (95% CI- 0.17-0.30) for PSV, and 0.19 (95% CI -0.05-0.41) for EDV. The sensitivity and specificity were respectively 84.6% and 86.7% for RI, 69.2% and 93.3% for PI, 80.0% and 65.4% for gray-scale sonography, and 93.3% and 65.4% for gray-scale plus RI (p = 0.013). Conclusions: Gynecologists must be careful in interpreting results from Doppler evaluation of ovarian masses because PSV and EDV present poor intratumoral reliability. The lower RI value, evaluated in at least two distinct sites of the tumor, was able to improve the performance of gray-scale ultrasound in differential diagnosis of ovarian masses.

Lymphatic Vessel Density and VEGF-C Expression are Significantly Different Among Benign and Malignant Thyroid Lesions

Thyroid cancer is the most frequent endocrine neoplasia worldwide. The route for metastasis and loco-regional invasion preferentially occurs by lymphatic vessels. For this reason, the assessment of lymphatic vessel density (LVD) is supposed to represent both a prognostic parameter and also a potential therapeutic target. In order to evaluate the value of LVD in benign and malignant thyroid lesions, we analyzed 110 thyroidectomy specimens using D2-40, a specific marker for lymphatic vessels and vascular endothelial growth factor C (VEGF-C), the most potent molecule of lymphatic proliferation. LVD was significantly different between papillary and follicular carcinomas in total (p = 0.045) and peritumoral area (p = 0.042). Follicular adenoma and follicular carcinoma showed an important difference of intra- (p = 0.019) and peritumoral (p = 0.033) LVD. VEGF-C was more markedly expressed in malignancies than in benignant lesions (p = 0.0001). Almost all cancers with high positive VEGF-C expression also exhibited increased peritumoral LVD (p = 0.049) when compared with the benignant lesions. Indeed, the high peritumoral LVD of malignant thyroid lesions is an important finding for surgery planning and supports the practice of total thyroidectomy in malignant thyroid neoplasm`s since the lymphatic peritumoral vessels definitely are an escape path for tumor cells.

Endobronchial leiomyoma: an unusual non-defining neoplasm in a patient with AIDS

Smooth muscle neoplasms are more frequent in human immunodeficiency infected children than in HIV seropositive adults. Endobronchial leiomyoma is a rare benign tumor in HIV infected adult patients. Epstein-Barr virus (EBV) has been implicated in the pathogenesis of these tumors. Here we describe an adult patient with HIV infection with atelectasis of the left upper pulmonary lobe as the first clinical expression of an intrabronchial leiomyoma. In this case, we can not show the association with EBV. Our report suggests that smooth muscle tumors as leiomyoma should be included in the differential diagnosis of endobronchial masses in AIDS patients.

Cellular schwannomas of the intracranial and intraspinal compartment: morphological and immunological characteristics compared with classical benign schwannomas.

The concept of cellular schwannoma as an unusual benign tumor is well established for peripheral nerves but has never been tested in neurosurgical series. In order to test the validity of this concept in cranial nerves and spinal roots we performed an analysis of the clinical and morphological characteristics of 12 cellular and 166 classical benign schwannomas. Immunohistochemical detection of antigen expression in Schwann cells including proliferating cell nuclear antigen (PCNA) was also performed. This study shows that cellular schwannomas in neurosurgical series manifest at a lower age than the classical benign variant and occur mainly in the spinal roots. Mitotic activity and sinusoidal vessels appear more frequently in cellular schwannomas and constitute with high cellularity, the most valuable criteria separating both entities. The postoperative course in both types of tumors was free of metastases or sarcomatous changes. Immunoexpression of S-100 protein, vimentin, epithelial membrane antigen and glial fibrillary acidic protein is not statistically different between the two variants. In contrast, PCNA is more highly expressed in cellular schwannomas. These These results confirm the concept that cellular schwannomas are a clinico-pathological variant of benign schwannomas and provide significant support for the introduction of this entity in neurosurgical oncology.