Immunohistochemical expression of p53, MDM2, Ki-67 and PCNA in central giant cell granuloma and giant cell tumor

Towards better understanding of giant cell granulomas of the oral cavity

Giant cell granulomas are enigmatic lesions of the oral cavity characterised by a peculiar combined proliferation of mononuclear and multinucleated giant cells in a mesenchymal stromal background. Central and peripheral giant cell granulomas may have similar pathogenesis and histology but differ in their location and biological behaviour. It is important to differentiate them from other giant cell lesions that can occur in the oral cavity, such as giant cell tumour of the bone, aneurysmal bone cyst, brown tumour of hyperparathyroidism, and giant cell lesions of Ramon syndrome, Noonan syndrome, neurofibromatosis and Jaffe-Campanacci syndrome. A recent insight into their molecular genetics and pathogenesis, with identification of KRAS, FGFR1 and TRPV4 mutations, allows for better diagnostic differentiation and opens the door to the use of pathway inhibitors in the treatment of recurrent or dysmorphic lesions. In this review, we provide an updated summary of the clinical and pathological features of oral cavity giant cell granulomas that help with their precise diagnosis and management.

Giant Cell Reparative Granuloma of Parotid Region Infiltrating the Zygomatic Bone: A case report

Introduction

Giant cell reparative granuloma is a rare, locally benign tumor with an aggressive behavior resembling malignant neoplasm, originating mainly from the mandible and maxilla; however, it can originate from other sites, such as zygomatic and temporal bones, with a young adult female predilection.

Case presentation

A 28-year-old female presented to the Department of Otolaryngology and Head and Neck Surgery with a history of a slowly enlarging swelling over the left parotid region for four months. Physical examination revealed a non-erythematous, non-tender, firm mass with no overlying skin changes. Fine needle aspiration cytology of the lesion revealed a multinucleated giant cell-rich tumor and the histopathological examination of an incisional biopsy from the mass confirmed giant cell reparative granuloma. Therefore, a total surgical excision of the mass with curating of the zygomatic and temporal bones was performed with uneventful postoperative course and regular follow ups for one year.

Conclusion

A growing mass in the parotid region in a young adult female with no history of trauma should raise the suspicion of giant cell reparative granuloma. Histopathological examination is the definitive tool for diagnosis, and surgical excision is the treatment modality of choice in such cases.

Renal Epithelioid Angiomyolipoma Undergoing Aggressive Clinical Outcome: The MDM2 Expression in Tumor Cells of Two Cases

Epithelioid angiomyolipoma (EAML) has been known as a potentially malignant tumor which occasionally recur and/or metastasize to other organs, and clinically and pathologically recognized as distinct entity. However, the mechanisms of recurrence and/or metastasis (recurrence/metastasis) has still remained unknown. Here, we report two cases of renal EAML associated with recurrence/metastasis, and three cases of EAML in kidney or liver without recurrence/metastasis. According to the previous histological predictive models of EAML, the primary tumor was classified as low risk group in one of the cases with recurrence/metastasis in spite of its malignant behavior. Therefore, we considered that further investigation about the mechanisms of recurrence/metastasis in EAML is required for a malignancy prediction. We focused on some cell-cycle modulators, including mouse double minute 2 homolog (MDM2), which is ubiquitin ligase well-known to promote malignant behaviors by p53 ubiquitination and degradation, and also other cellular processes including genomic instability and epithelial-mesenchymal transition in p53-independent manners in various human malignancies. Immunohistochemical evaluation revealed that MDM2 protein expression increased stepwise throughout every steps of metastasis/recurrence in both cases, although it was negative in primary tumors. In conclusion, this is the first study demonstrating that MDM2 could play an important role in the molecular mechanisms of recurrence/metastasis of EAML. Further analyses focusing on MDM2 pathway could contribute to the identification of novel prognostic factors and/or therapeutic targets in EAML patients.

Management of Central Giant Cell Granulomas of the Jaws: An Unusual Case Report with Critical Appraisal of Existing Literature

Central giant cell granuloma (CGCG) is an uncommon, benign but aggressive osteolytic neoplasm of the craniomaxillofacial region, histologically characterized by an abundance of evenly distributed multinucleated giant cells within a sea of spindle-shaped mesenchymal stromal cells, scattered throughout the fibrovascular connective tissue stroma containing areas of hemorrhage. A rapid diagnostic assessment, together with an adequate histopathologic verification, is essential to improve the management and the prognosis of this locally destructive lesion. A rare case of a large destructive CGCG involving the entire right angle of mandible, causing extensive bony resorption, and buccal, medial as well as inferior border cortical expansion with multiple perforations, in a young child is presented. It was treated successfully by enucleation and aggressive curettage followed by peripheral ostectomy preserving the continuity of the mandible. Two adjunctive measures were employed; first, chemical cauterization of the residual bony walls to prevent possible recurrence, for which this tumor is notorious, and second, placement of fresh autologous platelet-rich fibrin within the bony defect to hasten bone fill and reossification, thus obviating the need for a bone graft.

Recurrence of giant cell tumour of bone: role of p53, cyclin D1, β-catenin and Ki67

PURPOSE

To determine various clinical, radiographic, and pathological parameters which may indicate an increased risk of Giant cell tumour of bone (GCTB) recurrence after surgical therapy.

METHODS

The study included a total of 164 GCTB samples; 118 (72 %) primary tumours, and 46 (28 %) recurrences; which were analyzed on immunohistochemistry for expression of Ki67, p53, cyclin D1, and β-catenin.

RESULTS

Among 13 analyzed clinical, radiological, and histological variables, which presented possible predictive factors for the incidence of GCTB relapse, univariate logistic regression (ULR) extract three highly statistically significant parameters: 1) lesion localization, 2) nuclear p53 expression in mononuclear cells, and 3) nuclear cyclin D1 expression in giant multinuclear cells. The multivariate logistic regression (MLR), revealing that p53 expression in mononuclear cells was the most significant predictive factor (HR = 6,181 p < 0,001), the positivity of which indicated six times higher probability for recurrence in GCTB. The expression of cyclin D1 in giant cells, containing less than 15 nuclei, was also statistically significant (HR = 8,398, p = 0,038) for predicting the recurrence, and demonstrated eight times more frequent recurrence in positive tumours.

CONCLUSIONS

This study confirmed independent predicting factors for GCTB reccurence: p53 expression in mononuclear tumour cells and cyclin D1 expression in giant multinuclear cells. Results are new addition to generally known parameters, such as: localization of lesion, number of surgical interventions, clear destruction of cortex with the presence of extracompartmental lesion, and histological criteria for malignancy and can help in further research and treatment of GCTB.

Giant Cell Granuloma of the Anterior Skull Base: Need for Early, Maximal Surgical Excision: A Short Series of 3 Cases with Review of Literature

Giant cell granuloma is a rare benign granulomatous lesion of the bone. The local aggressiveness, potentiation with trauma and complex anatomy of the skull base makes the surgical management in this location challenging. We report a series of three cases along with the clinical presentation, radiological and histopathological findings and the management issues while dealing with this lesion. A review of literature reveals the rarity of the lesion, alternate management modalities and the outcomes for such lesion involving the jaw bones and the skull base. For best outcomes differential diagnosis from giant cell tumor and brown tumor of hyperparathyroidism is essential. Further it may be concluded that there is a need for maximal surgical excision to avoid recurrence as the second line management options are not as effective.

Immunohistochemical comparison of p53, Ki-67, CD68, vimentin, α-smooth muscle actin and alpha-1-antichymotry-psin in oral peripheral and central giant cell granuloma

INTRODUCTION

Giant cell lesions are characterised histologically by multinucleated giant cells in a background of ovoid to spindle-shaped mesenchymal cells. There is a major debate whether these lesions are separate entities or variants of the same disease. Our aim was to study the nature of multinucleated and mononuclear cells from peripheral giant cell granuloma (PGCG), and central giant cell granuloma (CGCG) and giant cell tumor (GCT) of long bones using immunohistochemistry evaluation and to determine whether there is a correlation between recurrence and the markers used.

MATERIALS AND METHODS

Ki-67, p53, Vimentin, smooth muscle specific actin, CD68 and alpha-1-antichymotrypsin were used to study 60 giant cell lesions. These included 26 CGCG, 28 PGCG, and 6 GCT cases using an avidin-biotin-complex immunohistochemistry standard method.

RESULTS

All studied cases showed the same results except the percentage of Ki-67 positive mononuclear cells in PGCG was significantly higher than that of both CGCG and GCT (p<0.05). Interestingly, no statistical correlation between recurrence and the markers used was found.

CONCLUSION

Our results may suggest that these lesions have the same histogenesis. The mononuclear stromal cells, both histiocytic and myofibroblastic, are thought to be responsible for the behavior of these lesions whereas the multinucleated cells are considered as reactive. This might support the argument that PGCG, CGCG and GCT are different variants for the same disease. Further studies using molecular techniques are required to elucidate why some of these lesions behave aggressively than others.

Identification of differentially expressed genes and their subpathways in recurrent versus primary bone giant cell tumors

Giant cell tumor (GCT) of the bone is a benign but locally aggressive bone neoplasm with a strong tendency to develop local recurrent and metastatic disease. Thus, it provides a useful model system for the identification of biological mechanisms involved in bone tumor progression and metastasis. This study profiled 24 cases of recurrent versus primary bone GCT tissues using QuantiGene 2.0 Multiplex Arrays that included Human p53 80-Plex Panels and Human Stem Cell 80-Plex Panels. A total of 32 differentially expressed genes were identified, including the 20 most upregulated genes and the 12 most downregulated genes in recurrent GCT. The genes identified are related to cell growth, adhesion, apoptosis, signal transduction and bone formation. Furthermore, iSubpathwayMiner analyses were performed to identify significant biological pathway regions (subpathway) associated with this disease. The pathway analysis identified 11 statistically significant enriched subpathways, including pathways in cancer, p53 signaling pathway, osteoclast differentiation pathway and Wnt signaling pathway. Among these subpathways, four genes (IGF1, MDM2, STAT1 and RAC1) were presumed to play an important role in bone GCT recurrence. The differentially expressed MDM2 protein was immunohistochemically confirmed in the recurrent versus primary bone GCT tissues. This study identified differentially expressed genes and their subpathways in recurrent GCT, which may serve as potential biomarkers for the prediction of GCT recurrence.

Detection of the Epstein-Barr virus and DNA-topoisomerase II- α in recurrent and nonrecurrent giant cell lesion of the jawbones

The aims of this study were to determine whether the expression of Topo II-α correlates with presence of EBV in giant cell lesion of the jawbones and whether it is predictive of clinical biologic behavior of these lesions. Paraffin-embedded tissues from 8 recurrent and 7 nonrecurrent cases of bony GCLs and 9 peripheral giant cell lesions (PGCLs) as a control group were assessed for the expression of EBV and Topo II-α using immunohistochemistry. The results showed positive staining for Topo II-α in mononuclear stromal cells (MSCs) and multinucleated giant cells (MGCs). Student t-test showed that mean Topo II-α labelling index (LI) in recurrent cases was significantly higher than that in non-recurrent cases (P = 0.0001). Moreover, Spearman's correlation coefficients method showed a significant correlation between DNA Topo II-α LI and both of gender and site in these lesions. Moderate EBV expression in relation to the highest Topo II-α LI was observed in two cases of GCT. It was concluded that high Topo II-α LIs could be identified as reliable predicators for the clinical behavior of GCLs. Moreover, EBV has no etiological role in the benign CGCLs in contrast to its role in the pathogenesis of GCTs.

Giant cell tumor of bone: a basic science perspective

Comprehending the pathogenesis of giant cell tumor of bone (GCT) is of critical importance for developing novel targeted treatments for this locally-aggressive primary bone tumor. GCT is characterized by the presence of large multinucleated osteoclast-like giant cells distributed amongst mononuclear spindle-like stromal cells and other monocytes. The giant cells are principally responsible for the extensive bone resorption by the tumor. However, the spindle-like stromal cells chiefly direct the pathology of the tumor by recruiting monocytes and promoting their fusion into giant cells. The stromal cells also enhance the resorptive ability of the giant cells. This review encompasses many of the attributes of GCT, including the process of giant cell formation and the mechanisms of bone resorption. The significance of the receptor activator of nuclear factor-κB ligand (RANKL) in the development of GCT and the importance of proteases, including numerous matrix metalloproteinases, are highlighted. The mesenchymal lineage of the stromal cells and the origin of the hematopoietic monocytes are also discussed. Several aspects of GCT that require further understanding, including the etiology of the tumor, the mechanisms of metastases, and the development of an appropriate animal model, are also considered. By exploring the current status of GCT research, this review accentuates the significant progress made in understanding the biology of the tumor, and discusses important areas for future investigation.

Increased TNF-α, IL-6 and decreased IL-1β immunohistochemical expression by the stromal spindle-shaped cells in the central giant cell granuloma of the jaws

Objectives: the exp ress ion of the osteoclastogenic cytokines TNF-α, IL-6 and IL-1β were immunohistochemically evaluated in periph eral (PGCG) and central (CGCG) giant cell granulomas of the jaws in order to determine diff erences between these two lesions and between the two distinct tumor cell populations (multinucleated giant cells, MGCs and stromal sp indle-sh aped cells). Study Design: Paraffin-embedd ed tiss ue sections from 40 PGCG and 40 CGCG were immunohistochemically stained using antibodies against TNF-α, IL-6 and IL-1β. The percentage of positively stained cells and the staining intensity were ass ess ed to provide a combined immunoreactivity score value. Results: TNF-α, IL-6 and IL-1β were exp ress ed in all lesions. The CGCG compared to the PGCG sh owed significantly increased exp ress ion of TNF-α and IL-6 and decreased exp ress ion of IL-1β by the sp indle-sh aped cells and increased exp ress ion of IL-1β by the MGCs. The MGCs demonstrated in comparison to the stromal sp indlesh aped cells significantly increased exp ress ion of all three cytokines in both PGCG and CGCG. Conclusions: The proinflammatory cytokines TNF-α, IL-6 and IL-1β seem to be involved in the growth process of PGCG and CGCG of the jaws. A poss ible alteration in the sy nthesis or/and activity of these cytokines by the stromal sp indle cells in the CGCGs may enhance osteolys is through the stimulation of osteoclast progenitor cells, given the fact that the intraoss eous lesions cause bone resorption.

Key words: Giant cell granuloma, giant cell tumor, multinucleated giant cells, jaw, TNF-alpha, IL-6, IL-1beta, immunohistochemistry.

Quantitative analysis of argyrophilic nuclear organizer regions in giant cell lesions of jaws

BACKGROUND

Giant cell lesions of the jaws are considerably similar according to histopathologic characteristics yet show different clinical behaviors. These lesions include central giant cell granuloma (CGCG), aneurysmal bone cyst, Cherubism, and Brown tumor associated with hyperparathyroidism. The present study aimed to investigate AgNORs count in these lesions as a proliferative marker and to determine whether it can be used to discriminate between them or not.

METHODS

Forty-one cases of giant cell lesions of jaws were retrived from Oral Pathology Department (1987-2007). They included 21 cases of CGCG, eight cases of aneurysmal bone cyst (ABC), six cases of Cherubism, six cases of Brown tumor. The mean AgNORs count was calculated for all cases. To compare mean AgNORs in groups of lesions, ANOVA test was performed.

RESULTS

Mean AgNOR counts were: (0/85 +/- 0/29) in CGCG, (0/76 +/- 0/32) in ABC (0/87 +/- 0/10) in Cherubism and (0/82 +/- 0/16) in Brown tumor. A significant difference was not observed in AgNOR counts among these groups of lesions.

CONCLUSIONS

Jaws giant cell containing lesions have no acceptable differences in mean AgNORs.

Centrosome abnormalities in giant cell tumour of bone: possible association with chromosomal instability

Giant cell tumour of bone, a benign but potentially aggressive neoplasm, shows an increasing rate of chromosomal aneusomy that correlates with clinical course. Mechanisms that generate chromosomal instability in giant cell tumour of bone are poorly understood. One possible cause of chromosomal instability is an error in mitotic segregation due to numeric and/or functional abnormalities of centrosomes. Centrosome alteration is a common phenomenon in many cancers and has a major role in the development of chromosomal instability in cancer cells. To gain an insight into the possible mechanism for the generation of chromosomal instability in giant cell tumour of bone, we analysed 100 cases, including 57 primary nonrecurrent, 35 recurrent and 8 malignant giant cell tumour of bone cases. gamma-Tubulin immunohistochemistry was performed on tissue microarrays of 59 formalin-fixed paraffin-embedded cases, whereas pericentrin and gamma-tubulin fluorescent immunocytochemistry was carried out on 41 frozen smears. Fluorescent in situ hybridization was performed on 23 cases of pericentrin immunostained smears, allowing the simultaneous analysis of centrosomes and chromosome aberrations. Centrosome amplification was significantly higher in recurrent and malignant giant cell tumour of bones compared with nonrecurrent tumours (P<0.001). A comparison of the percentage of aneusomic cells with a normal centrosome content (4.7%) with that of aneusomic cells with centrosome amplification (6.4%) revealed no significant association between chromosome number alterations and centrosome aberrations (P=0.31). These findings indicate that centrosome alteration and frequency of aneusomy correlate with clinical behaviour; the lack of an association between centrosome amplification and chromosome number alteration suggests that alternative causative mechanisms produce genetic instability in giant cell tumour of bone.

Parathyroid hormone-related peptide (PTHrP), parathyroid hormone/parathyroid hormone-related peptide receptor 1 (PTHR1), and MSX1 protein are expressed in central and peripheral giant cell granulomas of the jaws

OBJECTIVE

Parathyroid hormone-related peptide (PTHrP) binds to the parathyroid hormone receptor type 1 (PTHR1), which results in the activation of pathways in osteoblasts that promote osteoclastogenesis through the RANK/RANKL system. RANK/RANKL expression has been shown in central giant cell granuloma of the jaws but PTHrP/PTHR1 has not. MSX1 protein is a classical transcription regulator which promotes cell proliferation and inhibits cell differentiation by inhibiting master genes in tissues such as bone and muscle. It has been implicated in the pathogenesis of cherubism, and its expression has been reported in a single central giant cell granuloma (CGCG) case. We aimed, therefore, to study the expression of those proteins by the different cellular populations of central and peripheral giant cell granulomas (PGCGs) of the jaws.

STUDY DESIGN

Twenty cases of CGCG and 20 cases of PGCG of the jaws were retrospectively examined by immunohistochemistry for the percentage of positively staining cells to antibodies for PTHrP, PTHR1, and MSX1, using a semiquantitative method.

RESULTS

In both CGCG and PGCG of the jaws, PTHrP and PTHR1 were abundantly expressed by type I multinucleated giant cells (MGC) and mononucleated stromal cells (MSC) with vesicular nuclei, whereas type II MGC and MSC with pyknotic nuclei expressed those proteins to a lesser extent. In both CGCG and PGCG of the jaws, MSX1 was abundantly expressed by type I MGC and MSC but type II MGC did not express it. A statistically significant difference (P < .05) was observed between CGCG and PGCG in the expression of PTHrP in type II MGC and MSC with pyknotic nuclei and in the expression of PTHR1 in type II MGC.

CONCLUSIONS

We suggest that in CGCG and PGCG of the jaws, PTHrP-positive immature osteoblasts activate PTHR1-positive mature osteoblasts to produce RANKL which interacts with RANK on the PTHrP/PTHR1-positive osteoclast-precursor cells found in abundance in the stroma of giant cell lesions and induces osteoclastogenesis through the classic pathway. Cells of the jawbones, the periodontal ligament, or the dental follicle, originating from the neural crest, may be involved in the pathogenesis of giant cell lesions of the jaws. Further study is required for these suggestions to be proved.

Giant cell tumor-like lesion of the urinary bladder: a report of two cases and literature review; giant cell tumor or undifferentiated carcinoma?

Summary

Giant cell tumor, excluding its prototype in bone, is usually a benign but local aggressive neoplasm originating from tendon sheath or soft tissue. Malignant behavior is uncommon. Visceral organ involvement including urinary bladder is rare. Giant cell tumors in visceral organs usually accompany epithelial tumors and the clinical behavior of giant cell tumor in urinary bladder is similar to its bone counterpart. Here, we report two cases of giant cell tumor located in urinary bladder in comparison with nine reported cases in the English literature. Concurrent noninvasive urothelial carcinoma was also described in all these previous reports and only one patient with follow-up died of disease. One of the two cases we present had no concurrent urothelial tumor at the time of diagnosis but had a history of a low grade noninvasive urothelial carcinoma with three recurrences. The histology of these two cases was similar to the giant cell tumor of bone and composed of oval to spindle mononuclear cells with evenly spaced osteoclast-like giant cells. Immunohistochemically, the giant cells showed staining with osteoclastic markers including CD68, TRAP, and LCA. Immunohistochemical expression of vimentin, CD68, LCA, and smooth muscle actin in mononuclear cells supported a mesenchymal origin with histiocytic lineage. The histologic and immunohistochemical properties in our cases as well as their clinical courses were consistent with a giant cell tumor. Consequently, tumors in urinary bladder showing features of giant cell tumor of bone may also be considered and termed "giant cell tumor".

Central giant cell granuloma of the jaws and giant cell tumor of long bones: an immunohistochemical comparative study

OBJECTIVE

This study investigated whether some components of the extracellular matrix and CD68 expression may drive the differences between the central giant cell granuloma (CGCG) of the jaws and giant cell tumor (GCT) of long bones, which present distinct evolution and clinical behavior.

MATERIAL AND METHODS

Eight cases of CGCG and 7 cases of GCT were selected and immunohistochemically analyzed to verify the pattern of expression of CD68, tenascin (Tn) and fibronectin (Fn).

RESULTS

A large number of the mononuclear cells and multinucleated giant cells CD68+ was observed in both of the studied lesions, indicating histiocyte/ macrophage origin. Seven cases of CGCG of the jaws showed intense staining of Fn, with uniform distribution predominantly. In all 7 cases of GCT of long bones the Fn displayed intense expression, with distribution pattern varying from uniform to reticulate/fibrillar. Six cases of CGCG were intensively stained by Tn, presenting focal expression in half of specimens, and reticulate/ fibrillar pattern of expression in 4 cases. All cases of GCT of the long bones presented intense expression of Tn, uniform distribution, and reticulate/fibrillar pattern of expression in four cases.

CONCLUSIONS

The immunoexpression of CD68 in mononuclear cells and multinucleated giant cells and staining patterns of Fn and Tn were similar in both entities. These findings indicate that these proteins could not be used to explain the differences between the CGCG of the jaws and GCT of the long bones.

Calcitonin: a non-invasive giant cells therapy

This paper reports four cases of central giant cell granuloma (CGCG) treated with calcitonin, attesting the efficacy and safety of its use as the chosen therapy for large CGCG. Four patients presenting CGCG treated with calcitonin were included in this study. Salmon calcitonin was administered for 6-28 months. It was observed determination of clear lesion limits for surgery, reduction and limitation of lesions. In aggressive cases, the calcitonin therapy was an excellent option, since it does not harm the patient, and a far less aggressive, complementary surgery may be performed in certain cases, avoiding life-long sequelae.

Immunohistochemical evaluation of giant cell tumors of the jaws using CD34 density analysis

PURPOSE

To compare CD34 expression in both aggressive and nonaggressive giant cell lesions of the jaws and identify any associations between tumor vascular density and biologic behavior.

MATERIALS AND METHODS

This was a retrospective study of subjects treated for giant cell lesions of the jaws at Massachusetts General Hospital from 1992 to 2006. The primary predictor variable was tumor classification (aggressive or nonaggressive); tumors were considered aggressive if they were greater than 5 cm in size, recurred after treatment, or exhibited 3 of the following: presence of root resorption, tooth displacement, or cortical bone thinning or perforation. Secondary predictor variables, recorded for each patient, were demographic, anatomic, and clinical measures. The outcome variable was the average CD34 staining density of histologic specimens quantified in 2 different areas. Descriptive and bivariate statistics were computed to identify predictors associated with vascular density.

RESULTS

The study sample was composed of 32 subjects with a mean age of 24.4 +/- 19.77 years (range: 2-83); 23 subjects (71.8%) were female. Of the tumors included, 11 (34.4%) were located in the maxilla, 21 (65.6%) in the mandible. Twenty-six tumors (81.2%) were classified as aggressive; the remainder (18.8%) were nonaggressive. There were no statistically significant differences between subjects with aggressive versus nonaggressive tumors with regard to age, gender, or location. Subjects with aggressive tumors had a significantly higher CD34 staining density (P = .02). None of the secondary predictors was associated with vascular density.

CONCLUSION

Vascular density of giant cell tumors of the jaws is significantly increased in aggressive tumors.

Central giant cell granuloma of the jaw: a review of the literature with emphasis on therapy options

Central giant cell granuloma (CGCG) is a benign lesion of the jaws with an unknown etiology. Clinically and radiologically, a differentiation between aggressive and non-aggressive lesions can be made. The incidence in the general population is very low and patients are generally younger than 30 years. Histologically identical lesions occur in patients with known genetic defects such as cherubism, Noonan syndrome, or neurofibromatosis type 1. Surgical curettage or, in aggressive lesions, resection, is the most common therapy. However, when using surgical curettage, undesirable damage to the jaw or teeth and tooth germs is often unavoidable and recurrences are frequent. Therefore, alternative therapies such as injection of corticosteroids in the lesion or subcutaneous administration of calcitonin or interferon alpha are described in several case reports with variable success. Unfortunately, randomized clinical trials are very rare or nonexistent. In the future, new and theoretically promising therapy options, such as imatinib and OPG/AMG 162, will be available for these patients.

An analysis of peripheral giant cell granuloma associated with dental implant treatment

This report discusses the management of a 21-year-old male who developed a peripheral giant cell granuloma (PGCG) associated with dental implant therapy, and reviews 4 previously reported cases of PGCGs developing in association with dental implant treatment. The patient described in this report was treated with multiple dental implants to manage severe oligodontia. Six years after implant placement, with the patient lost to follow-up, he presented to his dentist complaining of increasing swelling in the right mandibular vestibule. The patient was noted to have a large exophytic, ovoid-shaped, firm, smooth-surfaced, maroon-colored lesion. The lesion was found to be a PGCG associated with a dental implant. The lesion was treated successfully by explantation of the dental implant, complete excision of the lesion, and curettage of the underlying bony defect. No evidence of recurrence was seen over 12 months of follow-up.

Central giant cell granuloma of the jaws: A clinical, radiologic, and histopathologic study of 26 cases

The clinical behavior of central giant cell granuloma (CGCG) of the jaws is variable and difficult to predict. Clinical data and follow-up information of 26 patients with CGCG were analyzed. Histologic features were correlated with the clinical course of the disease. In 16 patients the CGCGs were asymptomatic; 10 lesions presented with aggressive growth, pain, massive swelling, root resorption, cortical perforation, and/or recurrence. These patients were younger and the lesions were larger than in the nonaggressive group. The histomorphometric analysis proved a significant increase in large giant cells, fractional surface area, and mitotic activity in aggressive CGCG lesions. Immunohistologic investigation (Ki-67 and p53 stain) revealed no significant differences. After surgical treatment, 3 patients with aggressive lesions developed a recurrence. The data show that clinical and histomorphometric features may be reliable indicators for the differentiation between aggressive and nonaggressive CGCG. This should be accounted for to improve the individual planning of the treatment and follow-up.

Giant cell tumor of the temporal bone--a case report

Background

Giant cell tumor is a benign but locally aggressive bone neoplasm which uncommonly involves the skull. The petrous portion of the temporal bone forms a rare location for this tumor.

Case presentation

The authors report a case of a large giant cell tumor involving the petrous and squamous portions of the temporal bone in a 26 year old male patient. He presented with right side severe hearing loss and facial paresis. Radical excision of the tumor was achieved but facial palsy could not be avoided.

Conclusion

Radical excision of skull base giant cell tumor may be hazardous but if achieved is the optimal treatment and may be curative.

Genetic profiling of central giant cell granuloma of the jaws

Central giant cell granuloma (CGCG) of the jaws is a central osteolytic lesion characterized histologically by multinucleated giant cells in a background of ovoid to spindle-shaped mesenchymal cells. Whether CGCG is a reactive lesion or a truly benign neoplasm remains undetermined, and the mechanism determining the onset of the disease remains unknown. To have more information regarding the genetic events involved in CGCG, the authors decided to perform an expression profile. Samples were derived from two surgically resected CGCG of the mandible. RNA extracted from a pool of three normal bone tissues was used as control. By using DNA microarrays containing 19,200 genes, the authors identified several genes whose expression was significantly up- or down-regulated. The differentially expressed genes cover a broad range of functional activities: cell cycle regulation; signal transduction; and vesicular transport. It was also possible to detect some genes whose function is unknown. The authors believe the data reported to be the first genetic portrait of CGCG of the jaws. Several markers have been identified that can potentially help in identifying some biological behavior (ie, quiescent versus aggressive lesions), as well as genes whose products could be potentially disease-specific targets for therapy. However, the authors think that more cases are needed, especially those comparing quiescent and aggressive lesions, before the exact profile of CGCG is known.

Systemic leukocyte activation in patients with central giant cell lesions

BACKGROUND

Central giant cell lesion (CGCL) is a reactive lesion of the jaws with an associated inflammatory infiltrate. Since cell circulation allows for intense communication between different compartments in the body, we investigated whether the CGCL would lead to phenotypic and/or functional changes in circulating leukocytes.

METHODS

We obtained lymphocytes and monocytes from CGCL patients and control subjects, to evaluate cytokine and adhesion molecule expression using flow cytometry.

RESULTS

Our results revealed that CD4(+) T cells and CD14(+) monocytes from CGCL express elevated levels of CD11a and CD11b, respectively, when compared with controls. The frequencies of CD4(+) T cells expressing interferon (IFN)-gamma and tumor necrosis factor (TNF)-alpha and the frequencies of CD4(+) and CD14(+) cells expressing interleukin (IL)-10 were increased in CGCL group, when compared with controls.

CONCLUSIONS

Our data indicate that, although CGCL is a localized lesion, the patients show systemic functional alterations in circulating leukocytes, suggesting their role in the inflammatory pathogenesis of CGCL.

Expression of apoptotic and cell proliferation regulatory proteins in actinic cheilitis

BACKGROUND

Actinic cheilitis (AC) is a pre-malignant lesion caused by ultraviolet (UV) radiation. The apoptotic proteins p53, bax, bcl-2, and the proliferation marker Ki-67, are known to play an important role in UV-exposed skin and carcinomas, therefore, these markers were assessed in AC and compared with normal lip and oral mucosa.

METHODS

AC (n = 13), normal lip (n = 7) and oral mucosa (n = 6) biopsies were stained immunohistochemically for p53, bax, bcl-2 and Ki-67, to determine their expression and distribution.

RESULTS

p53 was over-expressed in AC as compared with normal lip and oral mucosa (P < 0.003). Although bcl-2 expression was higher in AC than in oral mucosa (P < 0.002), it was significantly reduced as compared with normal lip (P < 0.04). Bax expression remained unchanged, and Ki-67 was significantly increased in AC and normal lip as compared with oral mucosa (P < 0.05).

CONCLUSION

The results suggest that DNA-damaged cells by UV radiation in AC are eliminated by apoptosis.

Riesenzellgranulom und Osteitis fibrosa cystica bei Hyperparathyreoidismus

BACKGROUND

Giant cell lesions of the bone present similar histological features. The differential diagnosis comprises central giant cell granuloma, giant cell tumor of bone, and osteitis fibrosa cystica (brown tumor) in combination with hyperparathyroidism. Since these lesions may mimic metastatic bone disease in patients with a history of cancer, a malignant process has to be considered. Since the treatment and prognosis of these entities-benign versus malignant osteolytic bone processes-differ greatly, definitive differential diagnosis is of utmost importance.

CASE REPORT

Two patients presenting with osteolytic lesions of the maxilla are reported here. In both cases a history of cancer (breast and prostate) suggested bone spreading of these malignant tumors. The clinical and histological findings were similar in both patients. One lesion was diagnosed as central giant cell granuloma, the other was found to be brown tumour in osteitis fibrosa cystica as an initial manifestation of hyperparathyroidism.

DISCUSSION

The presented cases demonstrate the difficulties in establishing the correct diagnosis of patients found to have osteolytic lesions of the jawbones which is critical for the appropriate management of these patients. The article discusses the different entities of osteolytic lesions of the jawbones and the necessary diagnostic and therapeutic approach.

Clinical and immunohistochemical characteristics of benign giant cell tumour of bone with pulmonary metastases: case series

PURPOSE

Giant cell tumour of bone with pulmonary metastases is rare. However, some patients die of pulmonary metastases, and histological examination cannot distinguish between benign tumour and malignant metastases. In this study, we present clinical and immunohistochemical findings associated with giant cell tumour of bone with pulmonary metastases.

METHODS

Five patients with benign giant cell tumour of bone with pulmonary metastases (one man and 4 women) were studied. Patients' ages ranged between 20 and 23 years (mean age, 21.8 years). Tumours were in the distal femur in 2 cases, and in the proximal tibia, distal tibia, and lumbar spine in one case each. The tissue specimens from primary tumours, recurrent tumours, and pulmonary metastases were studied using immunohistochemical techniques.

RESULTS

Three of the 5 primary tumours were of the spontaneous regression or growth cessation type, or the continuously slow-growing type, showing 4.2% to 6.2% of positive cells for Ki-67 after immunohistochemical staining. However, 2 patients with the rapid-growing type of disease died of pulmonary metastases; their primary, recurrent, and metastatic tumour specimens contained 9.0% to 11.5% of positive cells for Ki-67.

CONCLUSION

Three of the 5 primary tumours had a benign clinical pattern and immunohistochemistry. Two of the 5 patients died of pulmonary metastases, which had an aggressive clinical pattern and a high prevalence of positive cells in Ki-67. Examination of Ki-67 should be carried out for aggressive type of giant cell tumour.

Giant cell granuloma of the temporal bone: a case report with immunohistochemical, enzyme histochemical, and in vitro studies

A case of giant cell granuloma (GCG) that occurred in the right temporal bone is reported. The lesion showed histologic features identical to GCG. The multinuclear giant cells (MGCs) in the lesion showed strong reactivity with CD68, but patchy staining for myeloid/histiocyte antigen, alpha-1-antitrypsin, alpha-1-antichymotrypsine, and lysozyme. Activity of tartrate-resistant acid phosphatase was also consistently detected in the MGCs. Some of the mononuclear cells of the lesion exhibited similar immunocytochemical and histochemical reactivity as the MGCs. Ki-67 staining, however, was only detected in the mononuclear cells. The MGCs isolated from the lesion presented characteristic morphology of osteoclasts and possessed the ability to excavate bone in vitro. Thus, the MGCs in GCG appeared to express both macrophage- and osteoclast-associated phenotypes. The mononuclear cells were the major proliferative elements in the lesion and a subpopulation of these cells may represent precursors of the MGCs.