Mononuclear Giant Cells Research Articles

A Rare Case of Pancreatic Cancer: Undifferentiated Carcinoma of the Pancreas With Osteoclast-Like Giant Cells

Ductal adenocarcinoma of the pancreas is the most common pancreatic cancer, but undifferentiated carcinoma of the pancreas with osteoclast-like giant cells (UC-OGCs) is an exceedingly rare tumor. Microscopically, this tumor is characterized by the presence of two different cellular elements, namely, spindle or ovoid mononuclear cells and osteoclast-like giant cells (OGCs). Here, we report a rare case of UC-OGCs in a 79-year-old male with a one-month history of epigastric abdominal pain and unintentional weight loss. A blood workup revealed new-onset type 2 diabetes mellitus, and a computed tomography scan of the abdomen showed acute pancreatitis with a hypodense lesion in the head of the pancreas concerning for malignancy. He underwent an endoscopic ultrasound that also revealed a mass in the head of the pancreas, but no lymphadenopathy was observed. Biopsy was obtained and histopathology revealed UC-OGCs. We present this case to increase awareness of this rare clinical entity in patients presenting with acute-onset pancreatitis.

A Rare Case Study About Necrotizing Granulomatous Sarcoidosis

Sarcoidosis is a granulomatous disorder with an elusive etiology and pathogenesis. Classically, sarcoidosis is associated with non-caseating granulomas composed of mononuclear phagocytes, lymphocytes, and multinucleated giant cells. Necrotizing granulomas can also be associated with sarcoidosis but is scarcely reported in the medical literature. Necrotizing sarcoid granulomatosis is challenging to diagnose due to its rarity and similarity with other necrotizing disorders. Therefore, it is mainly considered a diagnosis of exclusion. We report one such case study, which could prompt further research to lay the course of treatment strategies for this disease. Moreover, our patient had a family history of sarcoidosis, which raises questions regarding possible genetic predisposition, and future work might help solve this medical mystery.

THE EARLY CELLULAR REACTION OF EYE TISSUES TO THE IMPLANTATION OF BIORESORBABLE DRAINAGES SATURATED BY IMMUNOSUPPRESSANTS WITH A SELECTIVE MECHANISM OF ACTION

Prolonged use of immunosuppressants with a selective mechanism of action is a promising strategy in the prevention of postoperative scarring in glaucoma surgery. In order to assess the cellular response of eye tissues to the implantation of bioresorbable drains saturated with cyclosporin A or everolimus, a filter-type hypotensive operation with implantation of polylactide-based drains was simulated in 12 rabbits. Drainages implanted in rabbits of the two experimental groups under study were pre-saturated with either cyclosporin A or everolimus. The control group consisted of animals that were implanted with drains not saturated with any drugs. On the 7th day after the operation, the animals were taken out of the experiment, the eyeballs were enucleated, and histological preparations stained with hematoxylin and eosin, as well as hematoxylin and Picrosirius-red were prepared. Using a score on a scale from 0 to 5, the cellular composition within the drainage material, the intensity of collagen synthesis in the drainage, the thickness of the capsule around the drainage, and the number of blood vessels were analyzed. In comparison with the control group, the study groups showed a significantly lower amount of mononuclear cells, fibroblasts and giant cells of foreign bodies, as well as a lower thickness of the capsules surrounding the drainage, up to their complete absence. In addition, the intensity of collagen synthesis inside the drainage material of the studied groups was significantly lower. The drains of the everolimus group were characterized by an extremely low density of viable cellular elements inside the implanted material and a complete absence of collagen. At the same time, no toxic effect of the substance on the surrounding tissues was found. Thus, the saturation of bioresorbable drainages based on polylactide with cyclosporin A and everolimus contributed to a decrease in the intensity of the formation of connective tissue elements both inside and around the drainage in the early postoperative period.

Fine needle aspiration of giant cell tumor involving thyroid gland: A case report of an unprecedented entity

Fine-needle aspiration (FNA) is commonly used to evaluate both primary thyroid lesions (PTLs) and secondary thyroid neoplasms (STNs). Although STNs are uncommon, metastases from various primary sites particularly the kidney, lung, and breast have been previously described. Giant cell tumor (GCT) is typically found in the metaphyseal-epiphyseal area of long bones that seldom involves thyroid. The typical cytological feature of GCT on FNA smears is highly cellular dual cell pattern consisting of mononuclear stromal cells and multinucleate osteoclast-like giant cells. By performing FNA of the left lobe of thyroid and clinico-radiological evaluation, we were able to diagnose a mass in a 40-year-old male patient as GCT based on cytological specimen. To the best of our knowledge, this is the first case that a GCT is identified in the thyroid gland by FNA initially.

Analysis of laser therapy effects in Sporothrix schenckii inactivation in vivo

Abstract Introduction Sporotrichosis is a common disease in tropical regions, caused by the fungus Sporothrix schenckii, affecting mainly rural workers and in direct contact with animals. Although treatment by indiscriminate use of oral antifungal drugs gives rise resistant isolates, leading to therapeutic failures and no remission of the disease. To evaluate the effectiveness of red low-power laser photobiomodulation in inactivation of S. schenckii infection induced in rodents. Methods Subcutaneously inoculation (2x103 S. schenckii/ml, 0.2 ml suspension) in the left footpad, in 27 mice divided into: control (n = 6, inoculated, without irradiation): early stage (not inoculated) = 1th biopsy; intermediate (9 weeks of evolution) = 2nd biopsy; final (21 weeks of evolution) = 3th biopsy. Treated (n = 21, inoculated and irradiated): early (13 weeks of evolution, 4 weeks after first irradiation) = 4th biopsy, intermediate (17 weeks of evolution, 8 weeks after first irradiation) = 5th biopsy, final (21 weeks of evolution, 12 weeks after first irradiation) = 6th biopsy. Serial irradiation with biopsies occurred every 30 days during each month, for three months. At the end of testing, the mice were euthanized, and histological analyzes of biopsies were performed. Results Each laser treatment session showed an inactivation of S. schenckii in treated animals compared to controls, with a regression of pseudoepitheliomatous hyperplasia, chronic inflammation, neutrophils, granulomas, giant mononuclear cells and steroid corpuscles. Conclusion The laser photobiomodulation was effective on S. schenckii inactivation, appearing to be an interesting therapeutic option in infections caused by this organism.

A case of hepato-renal syndrome associated with paratuberculosis in goat

Hepato-renal syndrome is a type of functional kidney failure due to acute or chronic liver diseases. A five year old female, crossbred goat was presented for post-mortem examination. On necropsy, icteric discoloration of carcass with enlarged liver, thickened jejunal and ileal mucosa and enlarged mesenteric lymph nodes were observed. Severe lipidosis of liver, hypertrophied hepatocytes, mononuclear cell infiltration of parenchyma and portal triads, fusion of villi, and extensive infiltration by mononuclear cells (epithelioid-macrophages, plasma cells and lymphocytes) and occasional giant cells were observed around a central caseated and calcified mass surrounded by fibrous tissue proliferation in the lamina propria of intestine. Calcification of the mesenteric lymph node was confirmed by Von Kossa staining as dark brown to black deposits. Severe glomerular and tubular degeneration, necrosis and presence of bile casts were observed in kidney, which was confirmed by Hall's staining. Diffuse golden yellow hemosiderin pigment deposits were observed in the splenic parenchyma, which wasconfirmedbyPerl's Prussianbluestainingasbluishblackpigments. Ziehl-Neelsenstainingrevealedacid-fastbacilli inthelamina propria of intestine. Immunohistochemistry (IHC) using anti-M. aviumsubspp. paratuberculosis immune serum showed positive brown signals intracellularly in the macrophages and epithelioid cells in the lamina propria of intestine. Demonstration of acid-fast organism and IHC confirmed paratuberculosisinfection and the cascade of injury consequent to the disease might have resulted in hepato-renal syndrome and death of the affected animal.

Effect of denosumab in giant cell tumor of bone

Giant cell tumor (GCT) of bone is a benign tumor with locally aggressive nature. The presence of mononuclear stromal cells and multinucleated giant cells is the microscopic characteristic feature of the GCT. It is an osteoclastic tumor with destruction of tumor is mediated by the receptor activator of nuclear factor kappa-B ligand (RANKL). Denosumab, a RANKL inhibitor, may reduce or eliminate tumor giant cells, the relative content of proliferative, densely cellular tumor stromal cells, replacing with nonproliferative, differentiated woven new bone. We report a case of GCT of the right distal femur in a 20-year-old female, treated with 6 cycles of denosumab as neoadjuvant therapy, which shows consolidation of the lesion and became amenable for extended curettage with phenol cauterization and cementing without going for any radical surgery shown to have very good functional outcome.

Giant-cell tumor of the patella: An uncommon cause of fracture

Primary patellar tumors are highly unusual. Most are benign neoplasms with giant-cell tumors being the most common, followed by chondroblastomas and aneurysmal bone cysts. Intralesional curettage and bone grafting is the treatment of choice for most giant-cell tumors in the patella. The use of adjuvants can reduce the high recurrence rate. This is a case report of a giant-cell tumor in a 61-year-old man who was diagnosed with a pathological fracture in the patella after minimal trauma. Extended curettage through an osteotomy made in the medial cortical of the patella was performed. The tumor cavity was filled with high viscosity bone cement and the medial cortical was repositioned. Histological analysis showed mononuclear cells and numerous multinucleated giant cells, confirming the diagnosis. Twenty-four months after surgery, the patient was asymptomatic and there was no evidence of local recurrence. Epidemiology, symptomatology, imagenology, histopathology, treatment options and prognoses of giant-cell tumors of the patella are discussed herein.

Calcific tendinitis of the rotator cuff.

Calcific tendinitis within the rotator cuff tendon is a common shoulder disorder that should be differentiated from dystrophic calcification as the pathogenesis and natural history of both is totally different. Calcific tendinitis usually occurs in the fifth and sixth decades of life among sedentary workers. It is classified into formative and resorptive phases. The chronic formative phase results from transient hypoxia that is commonly associated with repeated microtrauma causing calcium deposition into the matrix vesicles within the chondrocytes forming bone foci that later coalesce. This phase may extend from 1 to 6 years, and is usually asymptomatic. The resorptive phase extends from 3 wk up to 6 mo with vascularization at the periphery of the calcium deposits causing macrophage and mononuclear giant cell infiltration, together with fibroblast formation leading to an aggressive inflammatory reaction with inflammatory cell accumulation, excessive edema and rise of the intra-tendineous pressure. This results in a severely painful shoulder. Radiological investigations confirm the diagnosis and suggest the phase of the condition and are used to follow its progression. Although routine conventional X-ray allows detection of the deposits, magnetic resonance imaging studies allow better evaluation of any coexisting pathology. Various methods of treatment have been suggested. The appropriate method should be individualized for each patient. Conservative treatment includes pain killers and physiotherapy, or "minimally invasive" techniques as needling or puncture and aspiration. It is almost always successful since the natural history of the condition ends with resorption of the deposits and complete relief of pain. Due to the intolerable pain of the acute and severely painful resorptive stage, the patient often demands any sort of operative intervention. In such case arthroscopic removal is the best option as complete removal of the deposits is unnecessary.

Pathology of mycotic tracheitis in poultry: A case report

A case of mycotic tracheitis in an adult Rhode Island Red bird of about 20 weeks of age is described here. Necropsy revealed multiple circumscribed granulomatous nodules in the lungs and caseous plugs in the trachea. Microscopically there were fungal hyphae penetrating the tracheal mucosa together with a caseative plug having central necrotic mass adhering to the tracheal wall, foci of severe congestion and hemorrhage, fungal granuloma surrounded by mononuclear cell infiltration, giant cell, fungal hyphae and fibrous tissues were recorded. The fungal hyphae were also demonstrated by Grocott's methanamine silver stain.

A Case Report and Update of Giant Cell Fibroma

ABSTRACT A case report and update of giant cell fibroma The giant cell fibroma is a fibrous tumour with a distinctive clinicopathologic features which sets it apart from a conventional fibroma. It represents approximately 2% to 5% of all oral fibrous proliferations submitted for biopsy and is found predominantly in Caucasians and rarely in other races. Most often giant cell fibroma is mistaken for papilloma because of its papillary surface or fibroma because of its fibrous or elastic nature. Here, we report a case of giant cell fibroma, in the region of the incisive papilla, in a 30-year old autistic female. Key words: Giant cell fibroma, fibroma, histopathology, giant cells MUSBED 2014;4(1):58-62 Olgu Sunumu / Case Report INTRODUCTION The giant cell fibroma (GCF) is an interesting non-neoplastic lesion of the oral mucosa. It was first described by Weathers and Callihan in 1974. It was named for its characteristically large, stellate-shaped, mononuclear and multinucleated giant cells. Weathers and Callihan reviewed more than 2000 specimens at Emory University of which 108 specimens met the criteria for reclassification of GCF (1). Before Weathers’ and Callihans’ distinction of GCF, Eversole and Rovin compared and contrasted 279 fibrous hyperplastic gingival lesions, which falls into four categories: pyogenic granuloma, peripheral gingival fibroma, peripheral giant cell granuloma, and peripheral ossifying fibroma. Each has its own diagnostic histopathologic characteristics but exhibit overlap of clinical presentation (2,3). After distinguishing GCF among fibrous hyperplasias, Weathers and Campbell further elucidated the structure of the lesion when they studied them under light microscopy. They concluded again that dominant cells in the GCF were indeed unique, and that GCF merited its own classification (4,5). Giant cell fibroma is a fibrous oral benign asymptomatic pedunculated or sessile nodule less than 1 cm in size, more commonly seen in the mandibular gingiva and the lesion may persist for several years (6,7). The giant cell fibroma is a localized reactive proliferation of fibrous tissue, much like the irritation fibroma. It usually remains small and may have a broad base or be on a thick stalk. It is painless and often has lobules or nodules on its surface. The most characteristic histological feature is the presence of large spindle-shaped and stellate-shaped mononuclear cells and multinucleated cells (4). Very few case reports are seen regarding this tumour and controversy regarding the origin of this lesion continues (8). Here, we report a case of a 30-year old female who had

Pathology of Mycotic Tracheitis in Poultry

A case of mycotic tracheitis in an adult Rhode Island Red bird of about 20 weeks of age is described here. The bird had a history of dyspnoea, gasping and was dull prior to death. On postmortem examination lungs showed multiple circumscribed granulomatous nodules in the lungs and the trachea was occluded with caseous plugs. Microscopically there were fungal hyphae penetrating the tracheal mucosa together with a caseative plug having central necrotic mass adhering to the tracheal wall, foci of severe congestion and hemorrhage, fungal granuloma surrounded by mononuclear cell infiltration, giant cell, fungal hyphae and fibrous tissues were recorded. The fungal hyphae were also demonstrated by Grocott's methanamine silver stain.

Histopathological and Immunohistochemical Evaluation of Malignant Potential in Canine Aortic Body Tumours

In order to verify the malignant potential of aortic body tumours (ABTs) in dogs, 13 cases of canine ABT were studied histopathologically and immunohistochemically. The cases were divided into two groups according to the presence or absence of metastases to other organs at necropsy examination (metastasis group [n = 9] and non-metastasis group [n = 4]). The mean tumour weight:body weight ratio (TW:BW; g/kg) in the metastasis group (9.3 ± 6.7) was significantly higher than that in the non-metastasis group (1.5 ± 1.7) (P <0.05). In both groups, the neoplastic cells had malignant features including pleomorphism, anisocytosis and anisokaryosis, and mononuclear giant cells were present, showing invasion through the capsule and into the vascular lumen and other adjacent tissues. The mitotic index (MI), mean nuclear area (NA) for size value and coefficient of variation of the nuclear area (CVNA) for anisonucleosis did not differ significantly between the two groups. These findings show that anaplastic characteristics are present regardless of the tumour size or the presence or absence of metastases, suggesting that these tumours are generally malignant or potentially malignant. Immunohistochemical analysis using neuroendocrine markers including neuron-specific enolase, chromogranin A and S100 revealed no obvious differences in labelling intensity of neoplastic cells related to the presence or absence of metastases or associated with the mean TW:BW, MI, NA or CVNA value, indicating that immunohistochemistry has no practical value for determining the tumour grade of canine ABTs.

Detection of the Epstein-Barr Virus and DNA-Topoisomerase II-αin 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.

Andes Virus Infection of Lymphatic Endothelial Cells Causes Giant Cell and Enhanced Permeability Responses That Are Rapamycin and Vascular Endothelial Growth Factor C Sensitive

Hantaviruses primarily infect endothelial cells (ECs) and nonlytically cause vascular changes that result in hemorrhagic fever with renal syndrome (HFRS) and hantavirus pulmonary syndrome (HPS). Acute pulmonary edema during HPS may be caused by capillary leakage and failure of lymphatic vessels to clear fluids. Uniquely regulated lymphatic ECs (LECs) control fluid clearance, although roles for lymphatics in hantavirus disease remain undetermined. Here we report that hantaviruses productively infect LECs and that LEC infection by HPS causing Andes virus (ANDV) and HFRS causing Hantaan virus (HTNV) are inhibited by α(v)β(3) integrin antibodies. Although α(v)β(3) integrins regulate permeabilizing responses directed by vascular endothelial growth factor receptor 2 (VEGFR2), we found that only ANDV-infected LECs were hyperpermeabilized by the addition of VEGF-A. However, VEGF-C activation of LEC-specific VEGFR3 receptors blocked ANDV- and VEGF-A-induced LEC permeability. In addition, ∼75% of ANDV-infected LECs became viable mononuclear giant cells, >4 times larger than normal, in response to VEGF-A. Giant cells are associated with constitutive mammalian target of rapamycin (mTOR) activation, and we found that both giant LECs and LEC permeability were sensitive to rapamycin, an mTOR inhibitor, and VEGF-C addition. These findings indicate that ANDV uniquely alters VEGFR2-mTOR signaling responses of LECs, resulting in giant cell and LEC permeability responses. This suggests that ANDV infection alters normal LEC and lymphatic vessel functions which may contribute to edematous fluid accumulation during HPS. Moreover, the ability of VEGF-C and rapamycin to normalize LEC responses suggests a potential therapeutic approach for reducing pulmonary edema and the severity of HPS following ANDV infection.

Giant Cell Glioblastoma in the Cerebrum of a Pembroke Welsh Corgi

A 6-year-old, neutered female Pembroke Welsh corgi was presented with a 1-month history of ataxia and panting. The clinical signs progressed until the dog became anorexic, obtunded and exhibited circling to the left. At necropsy examination, a mass was detected in the left forebrain, impinging on the cribriform plate. Microscopically, the mass was composed of sheets of round to pleomorphic neoplastic cells with vacuolated cytoplasm. Nuclear atypia, anisocytosis and anisokaryosis were common. Numerous bizarre, multinucleated giant cells containing 60 or more nuclei and giant mononuclear cells were present. The matrix contained abundant reticulin. Immunohistochemistry revealed the neoplastic cells uniformly to express vimentin, and a small number of neoplastic cells expressed glial fibrillary acid protein. A diagnosis of giant cell glioblastoma was made. Although well recognized in man, this tumour has been documented rarely in the veterinary literature.

Penile Extramedullary Plasmacytoma in a Dog

Penile tumours are rare in dogs. Reported herein is a case of a penile extramedullary plasmacytoma (EMP) in a 5-year-old male cocker spaniel that was brought to a local hospital for an evaluation of a penile mass. The mass was approximately 1.3 cm in diameter at the time of presentation. In fine needle aspiration and histopathological examinations, the neoplastic cells showed eccentric round nuclei, a moderate amount of basophilic cytoplasm, and a peri-nuclear clear zone, consistent with plasma cell morphology. There was nuclear pleomorphism with mononuclear giant cells and occasional bi-nucleation. Round cells on the periphery of the mass demonstrated plasmacytic differentiation. Immunohistochemically, the neoplastic cells stained positive for MUM1 and light lambda chain. Based on the cytological and pathological observations, a diagnosis of penile EMP was established.

Radioactive iodine‐associated changes in thyroid on fine‐needle aspiration

A 64-year-old man with adenocarcinoma of the prostate status postprostatectomy was seen for routine screening. His medical history was significant for deep vein thrombosis, persistent hyperparathyroidism after parathyroid adenoma resection, and hyperthyroidism treated with radioactive iodine ablation 4 years before this visit. Ultrasound-guided fine-needle aspiration with a 20-gauge needle was performed on bilateral thyroid nodules at this follow-up visit. Cytologic examination of the resulting smears revealed a moderately cellular aspirate with cohesive, crowded sheets of atypical follicular epithelial cells on a background of inspissated colloid. Even on low-power examination, scattered atypical giant cells were evident (Fig. C1). Closer examination showed bizarre mononuclear giant cells with dense, oxyphilic cytoplasm (Fig. C-2). The nucleus was round to oval or elongated with a smooth nuclear membrane. The chromatin was slightly hyperchromatic with heterogeneous distribution and clearing with rare intranuclear inclusions. Nucleoli and nuclear grooves were not observed. A diagnosis of atypical follicular epithelial cells consistent with changes owing to therapy was rendered. Antithyroid drugs, radioactive iodine, and surgery are the mainstays of treatment for Graves’ disease. The cytomorphological features have been well described in the literature. 1–3 However, the cytologic characteristics vary

Achieving Efficient Anti-Adhesion in Re-Mediastinoscopy: An Experimental Study in Rats

Re-mediastinoscopy can be a difficult procedure due to fibrosis in the mediastinum. We have investigated the effect of an anti-adhesive barrier agent "hylan B gel" on the formation of adhesions after dissection in the superior mediastinum in a rat model. The study was conducted in 70 male Sprague-Dawley rats weighing 300 g. The strap muscles were divided by a midline cervical incision. The anterior and lateral aspects of the trachea were dissected to the level of the carina. Hylan B gel (Sepragel Sinus, Genzyme Company, Redgefield, NJ, USA) was used to create an anti-adhesive barrier. The rats who were subjected to surgery were sacrificed on postoperative days 14 and 28. All rats were previously divided into 5 groups: Sham group (n = 10); Group 1 (n = 15) surgery alone, sacrificed on day 14; Group 2 (n = 15) surgery and Sepragel, sacrificed on day 14; Group 3 (n = 15) surgery alone, sacrificed on day 28; Group 4 (n = 15) surgery and Sepragel, sacrificed on day 28. Histopathological analysis was performed to study the effect of the anti-adhesive agent. Scores were calculated based on collagen fibrosis, fibroblasts, granulation tissue, muscle alterations/inflammation, histiocytes, mononuclear giant cells, inflammation and vascular proliferation. Collagen fibrosis and fibroblast scores, which represent adhesions, were significantly higher in Groups 1, 2, 3, 4 than in the Sham group ( P < 0.01). The degree of adhesions on day 14 was found to be higher in Group 1 compared to Group 2 ( P < 0.01). Adhesions on day 28 were higher in Group 3 compared to Group 4 ( P < 0.01). There were no differences between groups with regard to foreign body reactions ( P > 0.05). Adhesions causing technical difficulty during re-mediastinoscopy can be reduced by the application of anti-adhesive agents during the primary procedure.

Touch Imprint and Fine Needle Aspiration Cytology of Giant Cell Tumor of Tendon Sheath: A Case Report

Giant cell tumor of the tendon sheath (GCTTS) is a slowly growing, benign soft tissue tumor. The tumors occur predominantly on the hands and feet. Although the clinical and histopathologic features are well-defined, only a few reports have described the cytologic appearance of this entity. A 26-year-old woman presented with a gradually developing circumscribed soft tissue mass near the proximal phalanx of her left little finger for one year. Imprint and fine needle aspiration (FNA) smears were obtained from the excisional biopsy specimen. The imprint smears were composed of predominantly singly dispersed bland mononuclear cells and several giant cells. The mononuclear cells were polygonal to round, and they showed a histiocyte-like appearance. Osteoclast-type multinucleated giant cells of various sizes were randomly scattered throughout the smears, and these cells contained 3 to 50 nuclei. Nuclear atypia and pleomorphism were absent in both the single and giant cells. Loose aggregates of hemosiderin-laden macrophages and binuclear stromal cells were also seen. The cytologic features of the FNA smears were similar with those of the imprint, Additionally, the FNA smears contained several clumps of densely collagenous stromal tissue that were seldom noted in previously reported cytologic material. The cytologic features were well-correlated with the concurrent histologic findings and the diagnosis of GCTTS was made. When the clinical and radiologic datas are integrated, the diagnosis of GCTTS can be strongly suggested, based on the pre-operative cytologic specimen.