Cellular morphology and relationships in giant-cell lesions of the jaws

Expression of CD34 and CD68 in peripheral giant cell granuloma and central giant cell granuloma: An immunohistochemical analysis

Background:

Central and Peripheral giant cell granulomas of jaws are uncommon, benign, reactive disorders that are characterized by the presence of numerous multinucleated giant cells and mononuclear cells within a stroma. The origin of the multinucleated giant cells is controversial; probably originating from fusion of histiocytes, endothelial cells and fibroblasts.

Objective:

To assess the expression of CD34 and CD68 in central and peripheral giant cell granulomas to understand the origin of these multinucleated giant cells.

Materials and Methods:

Twenty cases of Central and Peripheral giant cell granulomas were evaluated immunohistochemically for CD34 and CD68 proteins expression.

Results:

Immunopositivity for CD34 was seen only in cytoplasm of endothelial cells of blood vessels; whereas, consistent cytoplasmic immunopositivity for CD68 was seen in few stromal cells. Statistical significance was seen in mean number of multinucleated giant cells, mean number of nuclei in multinucleated giant cells, CD68 expression and ratio of macrophages to multinucleated giant cells among two lesions.

Conclusion:

Although the central giant cell granulomas share some clinical and histopathological similarities with peripheral giant cell granulomas, differences in mean number of nuclei in multinucleated giant cells and CD68 immunoreactivity may underlie the distinct clinical behavior.

Clinically aggressive central giant cell granulomas in two patients with neurofibromatosis 1

BACKGROUND

Neurofibromatosis 1 (NF1) is an autosomal dominantly inherited disorder caused by a spectrum of mutations affecting the Nf1 gene. Affected patients develop benign and malignant tumors at an increased frequency. Clinical findings include multiple cutaneous café-au-lait pigmentations, neurofibromas, axillary freckling, optic gliomas, benign iris hamartomas (Lisch nodules), scoliosis, and poorly defined soft tissue lesions of the skeleton. Kerl first reported an association of NF1 with multiple central giant cell granulomas (CGCGs) of the jaws. There have since been 4 additional published cases of NF1 patients with CGCGs of the jaws.

CLINICAL CASES

We report on 2 patients who presented with NF1 and aggressive CGCGs of the jaws. In both cases, the clinical course was characterized by numerous recurrences despite mechanical curettage and surgical resection.

CONCLUSIONS

We review proposed mechanisms to explain the apparent association between NF1 and an increased incidence of CGCGs of the jaws. While the presence of CGCGs of the jaws in patients with NF1 could represent either a coincidental association or a true genetic linkage, we propose that this phenomenon is most likely related to NF1-mediated osseous dysplasia. Compared to normal bone, the Nf1-haploinsufficient bone in a patient with NF1 may be less able to remodel in response to as of yet unidentified stimuli (e.g. excessive mechanical stress and/or vascular fragility), and consequently may be more susceptible to developing CGCG-like lesions. Alternatively, the CGCG in NF1 patients could represent a true neoplasm, resulting from additional, as of yet unidentified, genetic alterations to Nf1-haploinsufficient bone.

Multinucleated giant cells in various forms of giant cell containing lesions of the jaws express features of osteoclasts

BACKGROUND

The nature and the mechanism involved in the formation of the multinucleated giant cells (MGCs) in various giant cell-containing lesions of the jaws are not fully understood. The aim of this study is to clarify the osteoclastic features of the MGCs in central giant cell granuloma (CGCG), peripheral giant cell granuloma (PGCG), cherubism, and aneurysmal bone cyst (ABC), and the mechanism underlying the interrelations between cellular components in the formation of the MGCs.

METHODS

Immunohistochemical study with a panel of antibodies including vacuolar H+-ATPase (V-ATPase), carbonic anhydrase II (CA II), Cathepsin K, matrix metalloproteinases-9 (MMP-9), CD68, and proliferating cell nuclear antigen (PCNA), and enzyme histochemical staining for tartarate-resistant acid phosphatase (TRAP) were applied on a total number of 53 cases of giant cell-containing lesions including CGCG (n = 34), PGCG (n = 6), cherubism (n = 7), and ABC (n = 6). In situ hybridization was also carried out to detect the mRNA expression of the receptor activator of NF-kappaB ligand (RANKL), a newly identified cytokine that is shown to be essential in the osteoclastogenesis, its receptor RANK (receptor activator of NF-kappaB ligand), and its decoy receptor OPG (osteoprotegerin) in these four types of lesions.

RESULTS

Immunohistochemical and enzyme histochemical studies showed that both the MGCs and a fraction of mononuclear cells in these lesions were strongly positive for TRAP, V-ATPase, CA II, Cathepsin K, MMP-9, and CD68, while the spindle-shaped mononuclear cells were positive for PCNA. The results with in situ hybridization indicated that RANKL mRNA was mainly expressed in the spindle mononuclear cells while OPG was extensively distributed in both the MGCs and the mononuclear cells. RANK mRNA was expressed in the MGCs and some round mononuclear cells.

CONCLUSIONS

These results suggest that MGCs in the four types of giant cell-containing lesions of the jaws show characteristics of the osteoclast phenotype. The mononuclear stromal cells, which show TRAP positively, may be the precursors of the MGCs. RANKL, OPG, and RANK expressed in these lesions may play important roles in the formation of the MGCs. The similar characteristics and mechanisms in the differentiation of MGCs in these lesions also suggest that there might be a similar kind of pathogenesis involved in the formation of the MGCs in these lesions

Large giant cell reparative granuloma of the petrous bone--case report

A 41-year-old man presented with a large mass bulging over the suprazygomatic temporal region. Neuroradiological examination showed that the huge extra-axial mass with osteolytic character originated from the upper surface of the petrous bone. Preoperative obliteration of the feeding arteries with super-selective intravascular embolization was helpful for the total removal of the tumor. Histological examination revealed that the tumor consisted of massive fibrohistiocytic proliferation with numerous heavily hemosiderin-laden macrophages and numerous multinucleated giant cells. The most probable diagnosis was giant cell reparative granuloma. Therefore, no postoperative irradiation or other adjuvant therapy was given.

A case of giant cell reparative granuloma of the petrous bone: demonstration of the proliferative component

BACKGROUND

Giant cell reparative granuloma (GCRG) is an uncommon benign lesion of the bone. It typically arises in the mandible and rarely involves the skull. The cytologic nature and genesis of the involved cells are poorly understood.

METHODS AND RESULTS

We report a case of GCRG in the petrous bone of a 3-year-old girl. One year following gross total removal, the granuloma recurred locally and was resected en bloc at the second surgery. Histologically, the lesion was composed of oval or spindle-shaped stroma cells admixed with a number of multinucleated giant cells. Immunohistochemical study demonstrated that 5.6% of the stroma cells, but none of the multinucleated giant cells, were positive for MIB-1 antibody.

CONCLUSION

These results suggest that this lesion expands by proliferation of the stromal component, with a growth rate roughly between those of the typical benign and malignant brain tumors. The cytologic nature of the cells comprising this uncommon disease remains to be elucidated.

Intravascular fibrin thrombi and endothelial cell damage in central giant cell granuloma

Two cases of central giant cell granuloma were studied ultrastructurally. The majority of vessels showed intravascular fibrin thrombi and endothelial cell damage, with gaps in their walls. Plasma, red cells and fibrin were seen subendothelially. The basal lamina was absent from endothelial cells where these components were in contact with their plasma membrane; otherwise it showed multiplication. It is suggested that the absence of basal lamina is the result of degeneration and that these vessels are probably venules and capillaries rather than lymphatics. Myofibroblasts were the dominant stromal cells. Giant cells had little phagocytic activity. It seems that the main function for the stromal cells is the repair of the haematoma and the damaged vessels. It is proposed that the term giant cell reparative granuloma is appropriate, but it should not be used indiscriminately for all jaw lesions containing giant cells.

Estrogen and progesterone receptor status of central giant cell lesions of the jaws

It is well known that the central giant cell lesion (granuloma) of the jaws has a distinct female predilection. In addition, occasional cases of central giant cell lesion have been reported to have undergone marked proliferation in pregnant patients and in those undergoing hormonal therapy. As such, we have evaluated 10 central giant cell lesions for the detection of estrogen and progesterone receptor proteins with the use of immunoperoxidase staining. Surprisingly, however, immunostaining for estrogen receptor protein was essentially negative in all cases examined. Although an occasional mononuclear cell stained weakly positive for estrogen receptor protein, these findings suggest that in most cases, factors other than a direct influence of the ovarian hormones, estrogen and progesterone, are responsible for the development and growth of these lesions.

Identification and semi-quantification of estrogen and progesterone receptors in peripheral giant cell lesions of the jaws

Cases of peripheral giant cell lesions of the jaws (PGCL) were evaluated for the detection of estrogen and progesterone receptor proteins (ERS/PRS) utilizing immunoperoxidase staining. Staining for ERS was strongly positive in three cases when examining the mononuclear cell population. Another two cases were weakly positive. In addition, an occasional ER + multinucleated giant cell could be observed in three of the cases examined. PRS immunoreactivity was essentially negative in all cases. It is well known that the PGCL has a marked female predilection. This, coupled with the present findings, gives further evidence that some PGCL may be at least partially under hormonal influence.

Features of central giant cell granuloma of the jaws xenografted in nude mice

In order that the growth pattern and histologic and ultrastructural differentiation of the central giant cell granuloma of the jaws be studied, tissue from three lesions was transplanted into nude mice. Xenografts were harvested at 3 weeks, 5 weeks, 8 weeks, and 13 weeks and examined histologically and ultrastructurally. Implants could be identified as firm subcutaneous nodules, but after 3 weeks began regressing. At 13 weeks, almost total regression had occurred. Histologically, grafts were well vascularized and there was no evidence of necrosis. Typical multinucleated giant cells disappeared at an early stage. The ultrastructural features of the grafts showed giant cells lying in close association with uninuclear cells, features suggestive of a fusion process. Many cells containing microfilaments at their periphery were identified in the original lesional tissue as well as in the xenografts. These cells strongly resembled myofibroblasts. Collagen bundles were seen within the cytoplasm of stromal cells. The observations suggest that the multinucleated giant cells represent a stimulus-dependent, differentiated end-stage cell population.

Peripheral giant cell granuloma. Clinicopathologic study of 224 new cases and review of 956 reported cases

The clinical and histopathological features of 224 new cases of peripheral giant cell granuloma were studied. In addition, the data from 956 previously reported cases in the literature were evaluated and compared with the present series. Females were found to be more commonly affected than males. All age groups were found to be affected with a relative predilection from 40 to 60 years of age. The mandible was more often affected than the maxilla. Clinically, the lesions were red in color, had a smooth surface and were rubbery or with a soft consistency. The most characteristic histologic features included a non-encapsulated highly cellular mass with abundant giant cells, inflammation, interstitial hemorrhage, hemosiderin deposits, mature bone or osteoid.

Central giant cell lesions of the mandible and maxilla: a clinicopathologic and cytometric study

Computer-assisted image analysis was used to measure four histopathologic parameters (number of giant cells, mean number of nuclei per giant cell, fractional surface area, and relative size index) in two groups of patients with central giant cell lesions in a search for possible histologic predictors of clinical behavior. The lesions of 22 patients were classified clinically into nonaggressive and the lesions of 10 patients were classified into aggressive categories in accordance with the method of Chuong and Kaban. The majority of patients with aggressive lesions had recurrent tumors within 2 years and/or experienced pain, root resorption, and cortical perforation. Giant cells were selected in 25 random high-power magnification (X400) fields and measured by means of the Leitz Texture Analysis System-Plus. Linear stepwise discriminant analysis was applied to each parameter studied. Clinically aggressive giant cell lesions were characterized by a higher number of giant cells and greater fractional surface area when compared with the nonaggressive tumors. With the use of the "jackknife" classification procedure, the accuracy of the two statistically significant parameters (number of giant cells and fractional surface area) in predicting the aggressiveness or the nonaggressiveness of our group of central giant cell granulomas was, respectively, 70% and 82%. This study provides further evidence that the use of cytometric analysis of giant cells may be helpful in predicting prognosis and in planning treatment for these often difficult-to-manage lesions.

Growth behavior and lineage of isolated and cultured cells derived from giant cell granuloma of the mandible

A central giant cell granuloma of the mandible was fractionated into its mononuclear and multinuclear cellular constituents. The cells were subsequently grown in tissue culture. Sections from the original lesion and the cultured cells were analysed histochemically and immunocytochemically. Acid phosphatase, non-specific esterase, Lysozyme and alpha-1-antitrypsin were employed as markers for cells of histiocytic origin and Factor VIII-related antigen served as an endothelial cell marker. The mononuclear cells were of 2 types; a spindle-shaped cell and a round macrophage-like cell. The giant cells and the macrophage-like cells had a limited life span in culture and survived for up to 2 and 5 weeks respectively. However, the spindle-shaped cells continued to proliferate with a doubling time of 48 h. The giant cells and the macrophage-like cells were identical in their staining characteristics and showed positive staining for all the histiocytic markers tested. In contrast, the spindle-shaped cells were negative for those markers. None of the 3 cell types stained positively for Factor VIII-related antigen. These findings suggest that the giant cells in giant cell granuloma of the jaw are reactive, fully differentiated end-cells that are probably derived from stromal macrophages. The histogenesis of the spindle-shaped cell is not yet known. It is also shown in this study that the histochemical and in vitro growth characteristics of the cells of central giant cell granuloma of the mandible are analogous to those of giant cell tumors of long bones.

Myofibroblasts in central giant cell granuloma of the jaws: an ultrastructural study

The ultrastructure of stromal mononuclear cells and giant cells were studied in two cases of central giant cell granuloma of the jaws. The majority of stromal cells superficially resembled fibroblasts, but also contained intracytoplasmic myofilaments with electron dense bodies similar to smooth muscle cells. These cells were referred to as myofibroblasts. The other type of mononuclear cells resembled macrophages. Many of the myofibroblast type cells appeared close to giant cells and signs of early fusion between them could be demonstrated. It is suggested from these results that the giant cells in central giant cell granuloma form and increase in size through fusion of these cells.

Hyperplastic lesions of the gingiva and alveolar mucosa. A study of 175 cases

175 'epulides' were studied clinically and histologically. The lesions were histologically reclassified into three groups: granulomatous, fibromatous and giant cell lesions. The granulomatous group was four times and the giant cell group 1.5 times more frequent in females. It is suggested that the expression epulis should be abandoned as a microscopic designation for lesions in the oral mucosa, as it is only a non-specific topographico-clinical concept comprising histogenetically and histomorphologically differing lesions and therefore does not represent a uniform group. The suggested new terms for the three types of hyperplastic lesions are oral mucosal granulomatous hyperplasias (including such diagnostic terms as granulomatous gingivitis, gingivitis of pregnancy, granuloma gravidarium, pyogenic granuloma, epulis angiomatosa and epulis telangiectaticum), oral mucosal fibrous hyperplasias (including such diagnostic terms as fibrous epulis, epulis fissuratum, fibroepithelial lesions, denture injury tumor and peripheral odontogenic fibroma) and oral mucosal giant cell hyperplasia (including such diagnostic terms as peripheral giant cell granuloma and giant cell epulis).

Giant cell (reparative) granuloma of the orbit

Clinically and histologically, there exists considerable controversy as to what constitutes a giant cell tumor. There is an increasing awareness that the term giant cell tumors should not be used indiscriminately in describing lesions of the mandible, maxilla, and facial bones which contain multinucleated giant cells. This paper reports a rare case of giant cell reparative granuloma of the orbit. The differentiation between giant cell reparative granuloma and the true giant cell tumor is discussed and a description of the visual symptomatology associated with these lesions of th sphenoid bone is presented. These tumors must be removed completely to prevent recurrence.

Electron microscopic study of peripheral giant-cell reparative granuloma

Six giant-cell tumors have been examined by electron microscopic methods in order to determine their histogenesis and to expand knowledge of cell structures. The examination of giant cells revealed an abundance of cell organelles, especially mitochondria. Apart from typical stromal cells, such as fibroblasts, macrophages, and mast cells, clusters of stromal "light" cells were often found with an intimate relation between their cell membranes. The role and function of these cells is not well known. Between fibroblasts of regular appearance with a small number of cytoplasmic organelles, others were found with an incrased number of mitochondria. These cells often formed aggregates. This suggests that giant cells develop through the association of stroma fibroblast cells.

[Central giant cell granuloma. Histochemical and ultrastructural study on giant cell function (author's transl)]

Multinucleated giant cells in giant cell granuloma are formed by cell fusion of capillary pericytes. In our present study we tried to analyze cell function and activity by histologic, histochemical, and electronmicroscopic examination of giant cells. Lysosomal enzymes such as acid phosphatase and amino-peptidase were found in giant cells which is in agreement with former work. By their lysosomal system giant cells are proved phagocytic. In addition, giant cells being localized at trabecular surfaces of newly formed woven bone may develop osteoclastic functions. The enzymatic and funcational resemblance of giant cells and multinucleated osteoclasts points to the possibility of a similar cytogenesis of both cell types.

[Central giant cell granuloma: histochemical and ultrastructural study on its histogenesis (author's transl)]

Until now numerous studies on central giant cell granuloma of jawbones have not been able to reveal the histogenesis of this tumourlike lesion. The aim of the present investigation in two surgically proven cases was to study this question by means of histochemical and electron-microscopic methods. Rather similar histochemical properties were shown in giant cells and pericytes of capillary sproute penetrating the granuloma. Cell fusion occurred between both cell types as was observed by electron microscopy. The process of cell fusion is defined by characteristic interdigitations of cell membranes. Therefore pericytes are believed to be the stem cells of multinucleated giant cells in giant cell granuloma. The abundance of giant cells usually occurring in the granuloma might be explained by plenty of capillary sprouts made up by clusters of pericytes. The factors inducing the pericytic cell fusion process are still unknown. The question arises whether cytogenesis of giant cells in giant cell granuloma might be similar in other giant cell lesions or even in the development of multinucleated osteoclasts.