Osteoclastoma-like giant cell tumor of the thyroid. Report of a case with prolonged survival following partial excision and radiotherapy

Undifferentiated hepatic carcinoma with osteoclast-like giant cells: A case report and literature review

Osteoclast-like giant cell tumor (OGCT) is a common bone tumor, occasionally observed in some extraosseous organs, but rarely involving the digestive system, especially the liver. Previously reported osteoclast-like giant cell carcinoma of the liver often coexists with sarcomatoid or hepatocellular carcinoma. Undifferentiated liver tumors with osteoclast-like giant cells (OGCs) are extremely rare. Due to its rarity, there is no consensus for diagnosis and treatment of undifferentiated liver tumors with OGCs. Definitive diagnosis comes from surgery, so there is often a long delay in diagnosis following the occurrence of symptoms. This case describes an extremely rare case of an undifferentiated liver tumor with OGCs in detail. It also summarizes the previously published cases based on liver tumors with OGCs from August 1980 to June 2021, providing extensive evidence to improve preoperative diagnosis and management options.

An expanded immunohistochemical profile of osteoclast-rich undifferentiated carcinoma of the urinary tract

Osteoclast-rich undifferentiated carcinoma of the urinary tract (ORUCUT) is a rare tumor composed of ovoid to spindle-shaped mononuclear cells with intermixed or focally clustered osteoclast-like giant cells. Previous studies have demonstrated that the mononuclear cells are neoplastic cells, while the giant cells are reactive cells of histiocytic lineage. The association between these tumors and classic urothelial carcinomas suggest that the mononuclear cells are derived from urothelial cells; however, no studies have been conducted to assess the immunohistochemical profile of ORUCUT with more specific urothelial markers. This study identified 21 cases of ORUCUT and performed immunohistochemistry for GATA3, uroplakin II, and thrombomodulin along with pancytokeratin (AE1/3) on all cases. Mononuclear cells stained positive in 20 cases (95%) for GATA3 and 19 cases (90%) for thrombomodulin. None of the mononuclear cells were positive for uroplakin II and only three cases showed focal positivity for AE1/3. The osteoclast-like giant cells were negative for GATA3, uroplakin II, thrombomodulin, and AE1/3, providing additional support to a reactive origin for these cells. Additionally, 15 cases (71%) were associated with either in situ or invasive urothelial carcinoma. This study provides an expanded immunohistochemical profile for ORUCUT and more definitively supports a urothelial origin for this tumor.

A large nonmetastatic anaplastic thyroid cancer with complete thyroidal confinement

Anaplastic thyroid cancer (ATC) is rare but extremely aggressive, which accounts for about 2% of all thyroid cancers yet nearly 50% of thyroid-cancer-associated deaths in the United States. The median survival time from diagnosis is 5 months, with a 1-year survival rate of only 20%. We report here a case of ATC in a 56-year-old man who survived a large ATC. Preoperative fine-needle aspiration biopsy study to a large right thyroid mass suggested ATC. Total thyroidectomy with radical lateral neck and central neck dissection removed a well-circumscribed 9.5 cm tumor without extrathyroidal extension or lymphovascular invasion. All 73 lymph nodes removed were negative for metastasis. The tumor consisted of highly pleomorphic, undifferentiated cells with large zones of necrosis and loss of thyroid transcription factor-1 and thyroglobulin expression. A focal well-differentiated component and PAX8 expression confirmed its thyroid follicular cell origin. Nine months after postsurgical adjuvant concurrent radiation therapy and chemotherapy, the patient remained well without clinical, biochemical, and radiographical evidence for cancer recurrence. This is an unusual case of ATC in that it is one of the largest ATC tumors reported to display mild pathologic behavior and relatively long-term patient survival.

Osteoclast-like giant cell carcinoma of the distal ureter

Extraskeletal osteoclast-like giant cell (OGC) tumors are uncommon and have mainly been found in the breast and pancreas. OGC neoplasms of the urinary tract are extremely rare. Most cases found in the renal pelvis and bladder are associated with either an in situ urothelial malignancy or a conventional high-grade urothelial carcinoma. These malignancies tend to be associated with a poor prognosis and disease course. To our knowledge, no cases of OGC tumors of the distal ureter only have been published. Here, we present the case of a 76-year-old man who underwent hand-assisted laparoscopic nephroureterectomy because of painless gross hematuria with right flank pain. Pathologic examination showed OGC carcinoma of the right distal ureter. No local tumor recurrence or distant metastasis was found at the 5-month follow-up.

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".

Giant cell tumor of the uterus: case report and response to chemotherapy

Background

Giant cell tumor (GCT) is usually a benign but locally aggressive primary bone neoplasm in which monocytic macrophage/osteoclast precursor cells and multinucleated osteoclast-like giant cells infiltrate the tumor. The etiology of GCT is unknown, however the tumor cells of GCT have been reported to produce chemoattractants that can attract osteoclasts and osteoclast precursors. Rarely, GCT can originate at extraosseous sites. More rarely, GCT may exhibit a much more aggressive phenotype. The role of chemotherapy in metastatic GCT is not well defined.

Case presentation

We report a case of an aggressive GCT of the uterus with rapidly growing lung metastases, and its response to chemotherapy with pegylated-liposomal doxorubicin, ifosfamide, and bevacizumab, along with a review of the literature.

Conclusion

Aggressive metastasizing GCT may arise in the uterus, and may respond to combination chemotherapy.

Cytology of anaplastic giant cell carcinoma of the thyroid with osteoclast-like giant cells--a case report

Anaplastic carcinoma of the thyroid is known for its highly aggressive behaviour and rapid spread. While the giant cell variant is a well recognized morphologic pattern, the presence of osteoclast-like giant cells is a rare occurrence. We report a case of anaplastic carcinoma of the thyroid with focal presence of osteoclast-like giant cells occurring in an elderly male patient, diagnosed on aspiration cytology.

Osteoclast-rich undifferentiated carcinomas of the urinary tract

Osteoclast-like giant-cell neoplasms of the urinary tract are rare. They are composed of ovoid or spindle-shaped mononuclear cells with evenly spaced osteoclast-like giant cells. Terminology, histogenesis, and biologic behavior of these tumors remain controversial. Six cases of osteoclast-like giant-cell neoplasms of the urinary tract were identified from the consultation files of two of the authors. Patients were all male and elderly (range 65-82), with the exception of one 39-year-old male. In all, 3/6 tumors developed in the bladder and 3/6 in the renal pelvis. Size ranged from 5 to 11 cm. One bladder and three renal pelvis tumors were high stage (pT3) at time of presentation. Adjacent to the osteoclast-like giant-cell neoplasm in the same specimen, all patients had urothelial carcinoma in situ and/or high-grade papillary urothelial carcinoma. Multinucleated cells had identical morphological and immunohistochemical properties of osteoclasts; positive for CD-68, LCA, CD51 and CD54, and negative for cytokeratins and EMA. Varying percentages of mononuclear cells expressed alpha-smooth muscle actin (4/6), desmin (1/6), S-100 (4/6), LCA (2/6) and CD68 (6/6). However, mononuclear cells were also positive for epithelial markers in 4/6 tumors (cytokeratins AE-1/AE-3, Cam 5.2, CK7 and/or EMA). p53 stained mononuclear tumor cells in three cases, paralleling the staining on the accompanying urothelial carcinoma. Ki-67 stained mononuclear tumor cells, but not osteoclast-like giant cells. Follow-up data were available in five cases. One patient developed recurrence of noninvasive urothelial carcinoma and is still alive. Four patients were dead due to disease within 15 months, three with distant metastases. The intimate association of these tumors with urothelial carcinoma along with their immunohistochemical profile supports an epithelial origin for the mononuclear cells and non-neoplastic reactive histiocytic lineage for the osteoclast-like giant cells.

Giant cell tumor of bone

Giant cell tumor is a common benign bone tumor that possesses specific features including location at the end of long bone, a strong tendency toward local recurrence, and the rare capacity to metastasize to the lungs. Preferred treatment usually consists of extensive curettage and filling of the cavity with bone graft or cement. Debate still exists about the usefulness of local adjuvant treatment. Functional outcome is usually very good.

[Osteoclastic giant cell tumour of the pancreas]

Osteoclast giant cell tumours are bone tumours that occur in adults, and that are considered benign by WHO but locally aggressive. Strictly identical tumours are described in the pancreas, without simultaneous bone localization. We report the case of a 62-year woman with an osteoclast giant cell tumour of the distal pancreas, without any epithelial component, which was diagnosed after pancreatic resection and with no signs of recurrence after a 24-month follow-up. These pancreatic tumours are rare, with a very poor prognosis, an unclear histogenesis; they are often confused with pleomorphic or undifferentiated pancreatic carcinomas including a component of osteoclast giant cell. These osteoclast giant cell tumours of the pancreas usually present as large cystic tumours. In certain cases, complete resection can result in long-term survival.

Thyroid anaplastic carcinoma transformed from papillary carcinoma in extrathyroid area

We report a 75-year-old male with anaplastic carcinoma in an extrathyroid area. Thyroid remained unchanged. The patient is alive without incident of tumor recurrence at 3.5 years after total resection and at 5 years after initial symptom. The tumor developed between the sternocleidomastoid muscle and common carotid artery, and was completely separated from the thyroid. The tumor location was consistent with a branchial cyst. The tumor consisted of two parts; an upper solid tumor and a deep cystic tumor. The former showed anaplastic carcinoma with osteoclast-like giant cells. The latter was consistent with thyroid papillary carcinoma. The center was intermingled with these two carcinomas. Anaplastic carcinoma cells were positive for vimentin and papillary carcinoma cells were positive for keratin, thyroglobulin, and thyroid transcription factor-1. These results remain insufficient to find any conclusions concerning the tumor nature; either ectopic thyroid carcinoma arising from a branchial cyst or occult thyroid carcinoma metastasis. This is rare case in which thyroid anaplastic carcinoma transformed from papillary carcinoma in an extrathyroid area.

Osteoclast-type Giant Cell Neoplasm of Salivary Gland. A Microdissection-based Comparative Genotyping Assay and Literature Review

Primary salivary gland tumors resembling giant cell tumor of bone are very rare and have unsettled histogenesis. Both mesenchymal and epithelial origins have been suggested. We review 14 cases in the English-language literature and report another case, the first of which to be studied by microdissection-based microsatellite analysis. One-half of the tumors have been associated with a carcinoma, usually salivary duct carcinoma and carcinoma ex pleomorphic adenoma. Significant differences between this tumor and giant cell tumor of bone were observed. Unlike giant cell tumor of bone, in which the nuclei of the mononuclear and giant cells are similar, those of salivary gland show obvious differences between the nuclei of mononuclear cells and osteoclastic giant cells. In addition and in contrast to giant cell tumor of bone, the mononuclear cells of giant cell tumor of salivary gland express epithelial markers (epithelial membrane antigen, EMA; carcinoembryonic antigen, CEA) and androgen receptor. Genotypically, the microsatellite pattern of the giant cell component is more akin to the carcinomatous component and does not resemble giant cell tumor of bone. Biologically, giant cell tumor of salivary gland tends to be more aggressive than giant cell tumor of bone. We conclude that giant cell tumor of salivary gland is an unusual carcinoma that is not related to giant cell tumor of bone.

Primary de novo malignant giant cell tumor of kidney: a case report

Background

Osteoclast-like giant cell tumors are usually observed in osseous tissue or as tumors of tendon sheath, characterized by the presence of multinucleated giant cells and mononuclear stromal cells. It has been reported in various extraosseous sites including breast, skin, soft tissue, salivary glands, lung, pancreas, female genital tract, thyroid, larynx and heart. However, extraosseus occurrence of such giant cell tumors in the kidney is extremely rare and is usually found in combination with a conventional malignancy. De-novo primary malignant giant cell tumors of the kidney are unusual lesions and to our knowledge this is the second such case.

Case Presentation

We report a rare case of extraosseous primary denovo malignant giant cell tumor of the renal parenchyma in a 39-year-old Caucasian female to determine the histogenesis of this neoplasm with a detailed literature review.

Conclusion

Primary denovo malignant giant cell tumor of the kidney is extremely rare. The cellular origin of this tumor is favored to be a pluripotential mesenchymal stromal cell of the mononuclear/phagocytic cellular lineage. Awareness of this neoplasm is important in the pathological interpretation of unusual findings at either fine needle aspiration or frozen section of solid renal masses.

Osteoclastoma-like Giant Cell Tumor of the Lung

The main components of an unusual form of lung tumor were osteoclast-like multinucleated giant cells and mononuclear stromal cells. Besides, scattered islands of moderately differentiated squamous cells also appeared. Both the mononuclear and the osteoclast-like giant cells reacted with antibodies against CD68 and vimentin, but did not react with antibodies against cytokeratin, EMA and CEA, or lysozyme and a-1-antitrypsin. The p53 and PCNA antigens were positive only in mononuclear cells and not the osteoclast-like giant cells, suggesting that mononuclear cells represent proliferating elements with histiocytic differentiation while osteoclast-like giant cells are stromal, presumably reactive components of the tumor.

Undifferentiated carcinoma with osteoclast-like giant cells of the pancreas and periampullary region

BACKGROUND

Undifferentiated carcinomas with osteoclast-like giant cells are rare pancreatic and periampulary neoplasms that morphologically mimic giant cell tumor of bone. Despite numerous publications based primarily on single case reports, the terminology, histogenesis, and biologic behavior of these tumors remain controversial.

METHODS

The authors studied one periampullary and nine pancreatic neoplasms of this type. Immunohistochemistry was performed on nine of the cases and clinical follow-up data was obtained in eight.

RESULTS

The neoplasms were large (average 9 cm), partially or completely multicystic, and hemorrhagic. Histologically, they were composed predominantly of ovoid or spindle-shaped bland mononuclear cells and evenly spaced osteoclast-like giant cells. However, three neoplasms had foci in which the nuclear pleomorphism of the mononuclear cells approached that observed in anaplastic spindle and giant cell carcinomas. Other histologic features included phagocytosis of the mononuclear cells by the osteoclast-like giant cells (in 7 of 10 cases), osteoid or bone formation (in 3 of 10 cases), and chondroid differentiation (in 1 of 10 cases). Four neoplasms had foci of conventional adenocarcinoma and two arose in preexisting mucinous cystic neoplasms of the pancreas. The mononuclear cells were positive for epithelial markers in six of nine tumors tested (cytokeratins AE-1, AE-3, Cam 5.2, and/or epithelial membrane antigen). They were negative for the histiocytic markers (CD-68, lysozyme) in all nine cases tested. In contrast, the osteoclast-like giant cells were positive for CD-68 in all nine cases, positive for lysozyme in four cases, and negative for cytokeratins (AE-1, AE-3, and Cam 5.2) in all nine cases. p53 stained the mononuclear tumor cells in three cases and MIB-1 stained the mononuclear tumor cells in four cases, but the osteoclast-like giant cells did not stain with either antibody in all nine cases tested. Most of the patients died of disease within 1 year of diagnosis; only 1 patient was alive and disease free 14 years after surgical excision.

CONCLUSIONS

The association of these tumors with conventional adenocarcinoma or mucinous cystic neoplasms, the histologic features, and the immunohistochemical profile supports an epithelial phenotype for the mononuclear cells and a reactive histiocytic lineage for the nonneoplastic osteoclast-like giant cells. These neoplasms, which are better classified as undifferentiated carcinomas, follow an aggressive clinical course; most patients die of disease within 1 year.

Giant cell tumor of bone: frequent actin immunoreactivity in stromal tumor cells

Although giant cell tumor (GCT) of bone is a well-recognized neoplasm with distinctive clinical and histopathological features, the origin of tumor cells, particularly of mononuclear cells, has not yet been established. An immunohistochemical study was carried out on 11 cases of GCT of bone to examine the cellular natures of stromal mononuclear cells. In all cases, stromal cells were positive for muscle actin (HHF35) or alpha-smooth muscle actin, and in eight of 11 cases, positivity was intense and extensive. The cell margin of osteoclast-like giant cells (OGC) was stained positively by muscle actin, in addition to intense and diffuse positive staining of the cytoplasm for KP1 (CD68), whereas alpha-smooth muscle actin exhibited a negative reaction on the OGC. In conclusion, the tumor cells with muscle actin and alpha-smooth muscle actin positivities are not rare but frequently numerous in the GCT of bone; whereas further observation is necessary to elucidate whether the stromal cells exhibit myofibroblastic cell differentiation exactly.

Uterine leiomyosarcoma with osteoclast-like giant cells: histopathological and cytological observations

A 56 year old woman presented with abnormal uterine bleeding. Except for a myomatous uterus, no other abnormalities were noted on physical examination and in radiographic and serologic studies. The hysterectomy specimen revealed an 8 cm uterine fundic tumor composed of two histologically different patterns that merged with one another; one was a well differentiated leiomyosarcoma and the other a mixture of osteoclast-like giant cells (OGC) and plump spindle cells whose cell borders blended, resembling the histology of giant cell tumor of bone. Immunohistochemical studies showed positive staining for muscle actin, alpha-smooth muscle actin, and KP-1 (CD68) in both the spindle cells and OGC. The latter also stained for alpha-1-antitrypsin and alpha-1-antichymotrypsin. These findings suggested that OGC may be formed by the fusion of spindle cells of leiomyosarcoma and also express histiocytic markers.

Renal cell carcinoma with osteoclast-like giant cells

Primary extraskeletal epithelial neoplasms with osteoclast-like giant cells are rare. We describe a case of renal cell carcinoma with a sarcomatoid component and non-neoplastic osteoclast-like giant cells. The giant cells were noted in both the conventional and the sarcomatoid components of the neoplasm. Immunohistochemical studies indicate that these cells are monocyte/histiocyte in origin and most probably a host stromal reaction to the neoplasm.

Stromal osteoclast-like giant cells in an adenosquamous carcinoma of the gallbladder

We report a case an adenosquamous carcinoma of the gallbladder that extended to the proximal transverse colon. Metastatic tumor was present in regional lymph nodes and the liver. Microscopically, the tumor was composed of malignant epithelial cells that were cytokeratin-, epithelial membrane antigen-, and carcinoembryonic antigen-positive. The adjacent desmoplastic stroma of the primary tumor, as well as the metastasis, contained giant cells that morphologically resembled osteoclasts. Immunohistochemical studies showed that the giant cells were cytokeratin-, epithelial membrane antigen-, and carcinoembryonic antigen-negative but weakly alpha 1-antichymotrypsin-positive. While tumors containing osteoclast-like giant cells have been described in the breast, lung, liver, and thyroid, this is the first report of a tumor with this morphology originating in the gallbladder. The presence of the giant cells adjacent to both the primary and metastatic tumor and not at any other location suggests that the tumor cells are producing a substance that induces the formation of the nontumoral giant cells.

Osteoclast-like giant cell tumour of the urinary bladder

We report two cases of osteoclast-like giant cell tumour of urinary bladder associated with papillary transitional cell tumours. Both cases were morphologically identical to giant cell tumour of bone. The giant cells stained strongly for acid phosphatase which was resistant to tartrate digestion, a staining reaction typical of osteoclasts. In view of the ability of urinary bladder to induce metaplastic and neoplastic bone, we believe that these tumours may represent extraosseous giant cell tumours of bone.

Pleomorphic carcinoma of the pancreas with osteoclast-like giant cells expressing an epithelial-associated antigen detected by monoclonal antibody 44-3A6

This article describes a case of pleomorphic adenocarcinoma of the pancreas, metastatic to the adrenal glands and liver, that has unique cytological and histological features. Cytology demonstrated numerous mononuclear and multinucleated tumor giant cells as well as numerous osteoclast-like giant cells. These features were also seen in the histological sections, as were numerous clear cells. Electron microscopy demonstrated features suggesting an epithelial origin of the epulis cells. Prominent immunoreactivity with the monoclonal antibody (MCA) 44-3A6 of these cellular constituents was seen in the aspirate and in the tissue sections. These data provide further evidence to support the epithelial origin of these cellular components.

Osteoclast-like giant cell tumor of the liver

A 66-year-old male with osteoclast-like giant cell tumor of the liver that arose in the non-cirrhotic liver is presented. The liver tests were almost normal, and plasma levels of alpha-fetoprotein and carcinoembryonic antigen were within normal limits. The findings of liver scan by 99mTc phytate, celiac angiography, and CT scans are described for the first time for this rare neoplasm, showing a large, unresectable liver tumor. Histologically, the tumor mainly consisted of osteoclast-like giant cells and mononuclear cells, which were focally arranged in a vaguely trabecular pattern and sarcomatous pattern. By an electromicroscopic study, however, no definitive evidence was obtained whether it arose from epithelial cells or nonepithelial cells. Various clinicopathological features were described and compared with previously reported cases including two cases arising in the liver.

Anaplastic carcinoma of the thyroid with osteoclast-like giant cells. An ultrastructural and immunohistochemical study

An unusual anaplastic thyroid carcinoma with osteoclast-like giant cells is reported in a 72-year-old woman. Monotonous proliferation of variously sized mononuclear tumor cells interspersed with numerous osteoclast-like multinucleated giant cells was dominant. A small area of papillary carcinoma merging with the anaplastic carcinoma was disclosed. Immunohistochemically, tumor cells forming papillary pattern were positive for both thyroglobulin and keratin. Cells and cell clusters positive for keratin were found in anaplastic carcinoma. Electron microscopically, the anaplastic carcinoma cells displayed prominent mitochondria, a rough endoplasmic reticulum, and intermediate cell junctions. The cell clusters formed irregular lumina into which numerous microvilli were extended and which contained colloid-like material. Occasionally incomplete basal laminae were present. Cell clusters showing transitional pictures from cell clusters to multinucleated giant cells and multinucleated giant cells engulfing mononuclear tumor cells were observed by both light and electron microscopy. Findings from this study support the conclusion that anaplastic tumor cells arise in preexisting differentiated thyroid cancer and that associated multinucleated giant cells are formed by the fusion of carcinoma cells.

Undifferentiated carcinoma of the lung with osteoclast-like giant cells

We treated a patient with undifferentiated carcinoma of the lung, with osteoclast-like giant cells resembling those of the giant cell tumor of bone. The clinical and morphologic characteristics of this case are documented, and the literature concerning this type of tumor is reviewed. The tumor differed histologically from the pleomorphic carcinoma, which occurs most commonly in the lung, and showed diverse pleomorphic manifestation with benign looking osteoclast-like multinucleated cells and bizarre giant cells. In addition, and undifferentiated carcinoma with a sarcoma-like appearance containing small areas of papillary adenocarcinoma was evident in the tumor.

Malignant osteoclastoma-like giant cell tumour of the renal pelvis

We report the fourth case of an osteoclastoma-like giant cell tumour of the renal pelvis. A special feature was that although thorough sampling of the tumour showed an osteoclastoma-like pattern throughout, it was intimately associated with carcinoma in situ change of the adjacent transitional epithelium and this provides further support for the view that these tumours are of epithelial derivation. However, immunohistological and ultrastructural studies failed to reveal epithelial features within the tumour cells and the possible significance of this finding is discussed.

Osteoclastic giant cell tumor of the pancreas. Aspiration cytology, light microscopy, and ultrastructure with review of the literature

The osteoclastic giant cell tumor of the pancreas is a rare primary neoplasm that by light and electron microscopy mimics giant cell tumor of bone. In the proper clinical setting, this lesion can be diagnosed by fine needle aspiration. Review of 10 cases reveals a female predominance, a median survival of 12 months, and a tendency for local invasion, rather than lymphatic or distant metastasis, and for invasion of large veins. An epithelial origin is favored for this malignant neoplasm, which expresses varying degrees of mesenchymal differentiation.

Giant cell tumor of the bladder associated with transitional cell carcinoma

We report in detail the first giant cell tumor associated with transitional cell carcinoma of the bladder. The giant cell tumor was composed of multinucleated giant and mononuclear stromal cells, and was morphologically indistinguishable from giant cell tumor of the bone. The giant and transitional cell carcinomas showed no evidence of recurrence or metastasis 8 months after transurethral resection. No histogenetic correlation between the cancers was found.

Breast cancer with osteoclast-like multinucleated giant cells

A case of breast cancer containing osteoclast-like multinucleated giant cells was examined cytologically, light and electron microscopically to find morphological evidences suggesting the origin of the giant cells. There were multiple evidences showing the same carcinomatous origin of each cells including osteoclast-like multinucleated giant cells.

Hepatocellular carcinoma with osteoclast-like giant cells

A case of dedifferentiated hepatocellular carcinoma with osteoclast-like giant cells resembling those of giant cell tumor of bone is presented. The clinicopathologic findings are described, and the literature concerning this type tumor is reviewed. The tumor differed histologically from a pleomorphic variant of hepatocellular carcinoma in that there were numerous osteoclast-like giant cells with numerous, small, uniform, benign-appearing nuclei. To the knowledge of the authors, there has been only one report of this type of tumor arising in the liver. The tumor contained a separate area of a histologically conventional hepatocellular carcinoma, in addition to the above giant cell areas.

Anaplastic carcinoma of the thyroid with osteoclast-like giant cells

An unusual malignant thyroid neoplasm with a morphologic resemblance to giant cell tumor of the bone is reported in a patient who presented with a rapidly growing thyroid mass and a history of pre-existing goiter. The light and electron microscopic studies disclosed areas of differentiated follicular carcinoma with gradual transition to undifferentiated carcinoma. Pleomorphic spindle-shaped cells and giant cells were accompanied by numerous osteoclast-like multinucleated giant cells. Desmosomes and interdigitating cell surfaces were apparent in the differentiated as well as undifferentiated areas on electron microscopy. These findings support an epithelial rather than a mesenchymal origin for this neoplasm.

Giant cell tumour (osteoclastoma) of the pancreas--an epithelial tumour probably of pancreatic acinar origin

A case of giant cell tumour of the pancreas has been studied. The light microscopical appearance of the tumour is indistinguishable from osteoclastoma of bone. Electron microscopy of the tumour shows many typical desmosomes between stromal cells. This is strong evidence of its epithelial nature. The cytoplasm of both the osteoclast-like giant cells and stromal cells contain abundant rough endoplasmic reticulum, many with dilated cisternae containing prominent dense granules. There are also some larger homogeneous granules, some of them electron-dense, in the cytoplasm of the cells. These findings when compared with the features of other cases of giant cell tumour of the pancreas studied by electron microscopy support the view that this epithelial tumour is of acinar origin.

Osteoclast-type giant cell tumour of the pancreas

A case of osteoclast-type giant cell tumour of the pancreas is described and the features of eight other previously reported patients are reviewed. Characteristically, these neoplasms are large at presentation and show focal haemorrhage and necrosis, but seem slow to give rise to metastases. Histological examination reveals numerous osteoclast-like giant cells set in a sarcomatous stroma, the appearances being similar to those seen in giant cell tumours of bone. They are distinct from pleomorphic giant cell carcinomas of the pancreas and may have a slightly better prognosis after resection than ordinary adenocarcinomas. The histogenesis of these rare tumours is unknown.

Giant cell tumor of the kidney

A multinucleated giant cell tumor developed in the left renal pelvis of a 60-year-old man. The tumor was morphologically indistinguishable from giant cell tumor of bone and considered to be both primary and benign, with a follow-up period of one year and no evidence of either recurrence or metastasis.

Giant cell tumor ("osteoclastoma") of the pancreas: a tumor of epithelial origin

Carcinomas of the pancreas with giant cells are not rare, but those containing osteoclast-like tumor cells are quite unusual. This report documents a pancreatic neoplasm comprising both easily recognizable well-differentiated adenocarcinoma and osteoclast-like tumor. The literature on the "osteoclastoma" of the pancreas is reviewed. Evidence for its epithelial deviation is supported strongly by the present case.

Osteoclastome-like giant cell thyroid carcinoma controlled by intensive radiation and adriamycin, in a patient with meningioma and multiple myeloma treated by radiation and cytoxan

The eighth cases of osteoclastome-like giant cell carcinoma of the thyroid, and the first one to be treated with adriamycin in addition to surgery and radiation, is reported. This rare variant of anaplastic thyroid carcinoma appeared in a patient operated on for meningioma and treated for multiple myeloma with cranial radiation and chronic administration of cytoxan.

Osteoclastoma-like giant cell tumor of the liver

A rare, osteoclastoma-like giant cell tumor developed in the macronodular cirrhotic liver of an 87-year-old man. Histogenetically, the tumor was considered to be of reticuloendothelial cell (Kupffer cell) origin. A brief review of the literature concerning the extraosseous giant cell tumors is included in this report.

Giant cell tumor of the ovary

A 31 year old woman with primary sterility was found, at operation, to have endometriosis of the Fallopian tubes and a giant cell tumor of the ovary, histologically indistinguishable from giant cell tumor of bone. The tumor is considered to be primary and benign, with a follow-up period of 4 1/2 years and no signs of recurrence or malignancy.

[Multinucleated giant cell tumor of the thyroid: an unusual anaplastic carcinoma (author's transl)]

Neoplasms of the thyroid with multinucleated, osteoclast-like giant cells, are rare. The numerous giant cells observed in these undifferentiated neoplasm have extensive eosinophilic cytoplasm and contain two to several hundred round or oval, uniform small nuclei. The clinical and morphologic data obtained from the two cases we describe and seven others collected from the literature are as follows: a) peak incidence in late adulthood; b) frequent association with a preexisting goiter (6 cases); c) rapid growth and fatal outcome within one year following diagnosis (5 cases); d) histologic pleomorphism with a background of uniform and spindle- or bizarre-shaped mononuclear cells; e) occasional coexistence of multinucleated giant cell tumor with well differentiated follicular carcinoma (1 case). Indirect evidence suggests that the multinucleated giant cells which characterize these unusual anaplastic carcinomas are epithelial in origin.

Metaplastic squamous cell carcinoma of bronchus simulating giant cell tumor of bone

A 57-year-old man underwent a right pneumonectomy for a bronchogenic carcinoma following bronchoscopy and bronchial biopsy. The tumor was a polypoid mass arising from the lower lobe bronchus. Microscopically it was characterized by mononuclear cells mixed with randomly distributed multinucleated giant cells similar to those seen in giant-cell tumor of bone. Also found were portions showing typical squamous cell and spindle cell carcinoma. Based on the light and electron microscopic findings, we suggest that the current case represents a metaplastic squamous carcinoma showing mesenchymal cell differentiation. A hypothesis on the histogenesis of pleomorphic carcinomas was presented. The problems of histological diagnosis generated by such a tumor should be emphasized.

The histologic spectrum, prognosis, and histogenesis of the sarcomatoid carcinoma of the pancreas

A series of 12 cases of pancreatic carcinoma with sacroma-like transformation were studied. Four distinctive histologic types were identified: spindle cell carcinoma, malignant giant cell tumor, pleomorphic giant cell carcinoma, and round cell anaplastic carcinoma. The spindle cell carcinoma had a predominance of malignant spindle and undifferentiated cells. Hemorrhage and sarcomatoid stroma with abundant osteoclast-like giant cells were the features in the malignant giant cell tumor. The pleomorphic giant cell carcinoma was characterized by abundant malignant giant cells. The round cell anaplastic type was formed by monotonous sheaths of small, round, and plump cells with rare giant cells. The first three types are considered to be ductal in origin, whereas the fourth type is believed to arise from acinar or possibly insular tissue. The differential diagnosis includes various types of true sarcoma. Although the malignant giant cell tumor of the pancreas might have a better prognosis, the prognosis in the other three types does not differ significantly from that of the ordinary type of pancreatic carcinoma.