Fine needle aspiration and touch imprint cytology of a malignant fibrous histiocytoma of the spermatic cord. Case report

BACKGROUND: No cytologic reports on spermatic cord sarcomas have been published. CASE: A 64-year-old man presented with a slowly growing, painless, left spermatic cord enlargement. Fine needle aspiration (FNA) obtained < 1 mL of bloody fluid consisting of solitary, mark-edly anaplastic and pleomorphic tumor giant cells occasionally arranged in small fragments. Rare atypical spindle cells could be observed. Some reactive lymphocytes were observed intermingled with tumor cells. Immunohistochemistry displayed vimentin reactivity and negativity for keratins and leukocytic common antigen. The specimen removed showed a well-circumscribed, 30-mm, yellowish solid tumor. Touch imprints displayed pleomorphic tumor cells showing intense anisonucleosis; a moderate amount of clear, sometimes microvacuolated cytoplasm; and tissue fragments with a storiform pattern. Histologic examination revealed microscopic and immunohistochemical features of malignant fibrous histiocytoma (MFH) arising in soft tissues of the spermatic cord. CONCLUSION: FNA of a spermatic cord lesion may reveal a pleomorphic sarcoma. A pleomorphic appearance together with some spindle elements and compatible immunocytochemistry could help diagnose spermatic cord MFH. This is one of the few reports dealing with FNA cytology of paratesticular tumors and the first report, to the best of our knowledge, showing the cytologic characteristics of a case of spermatic cord MFH.     

Scrape cytology of elastofibroma. Report of a case with diagnostic cytologic features.

BACKGROUND: Elastofibroma is a benign, soft tissue tumor that occurs most frequently in the subscapular area in elderly people. To the best of our knowledge, in only two cases has the cytology been reported. The aim of this report is to describe the characteristic cytologic findings of elastofibroma and to discuss the usefulness of elastin stain in scrape smears. CASE: A 72-year-old female had bilateral masses in the lower subscapular area. Scrape smears from a cut surface of the resected masses revealed abundant, "wormlike" or "braidlike" material with central cores with Papanicolaou stain in an intraoperative consultation. Various-sized, petaloid or crystalloid globules were also present. Those elastic fibers were strongly positive for elastin stain in cytologic preparations. CONCLUSION: Elastofibroma can be diagnosed cytologically, and elastin-stained, scrape cytologic preparation is especially useful in such a case.     

Scratch cytologic findings on surgically resected solitary fibrous tumors of the pleura

OBJECTIVE: To ascertain the cytologic characteristics of solitary fibrous tumors of the pleura (SFTPs) on smear preparations. STUDY DESIGN: Fine needle aspiration cytology (FNAC) was initially attempted preoperatively in five cases, but the specimens were inappropriate for interpretation because only a few tumor cells were obtained. Therefore, scratch smears made at the time of operation were used. Papanicolaou and immunocytochemical staining was performed in all 10 cases, 2 of which were malignant. RESULTS: As expected, cellular tumors yielded more cells. The cytologic appearance was variable, showing spindle/bipolar, dendritic/stellate and intermediate cells. Atypical cells reminiscent of sarcoma were also present in cellular, benign tumors. Highly atypical epithelioid cells were obtained in two malignant cases. Immunocytochemically, the tumor cells were positive for CD34 and vimentin and negative for cytokeratin, regardless of histologic differences and cell shape. CONCLUSION: It seems difficult to diagnose SFTPs with certainty by FNAC, partly because the cell morphology of SFTPs resembles a wide variety of heterogeneous groups of spindle cell tumors and partly because only a few tumor cells were available in the FNAC specimens in the present study. However, a cytologic diagnosis of SFTP is possible if cytologic preparations yield CD34-positive cells with spindle/bipolar or dendritic/stellate morphology.     

Fine needle aspiration cytology of low grade fibromyxoid sarcoma. Report of a case with histologic correlation

BACKGROUND: Low grade fibromyxoid sarcoma, first described in 1987, is a rare sarcoma characterized by a bland and deceptively benign histologic appearance but with aggressive behavior. CASE: A 51-year-old female presented with a history of a recurrent and slowly growing mass in the left foot. Fine needle aspiration biopsy showed an abundant myxoid background with occasional thick bands of collagen. Tumor cells present in the myxoid background were spindle shaped, with focally mild or a light degree of nuclear enlargement, hyperchromasia and pleomorphism CONCLUSION: Low grade fibromyxoid sarcoma has particular cytologic features. Besides a careful cytologic evaluation of all the components, clinical and radiographic correlation is necessary to make the correct diagnosis.     

Fine needle aspiration of myofibroblastoma of the breast in a man. A report of two cases.

The cytopathologic features of fine needle aspiration biopsy of two myofibroblastomas of the breast in men are described. The cytologic findings consisted of monomorphic spindle cells with ovoid, grooved nuclei, isolated or in clusters, with an ill-defined, short fascicular pattern and abundant acellular, myxoid-appearing material. Atypical features were absent. No epithelial elements were present. We emphasize the value of aspiration cytology in association with clinical and mammographic data to establish a definitive diagnosis of this uncommon entity. This benign tumor should be considered in pure spindle cell, nontypical fine needle aspiration biopsy specimens of breast masses with sharp demarcation from the surrounding tissue, especially in men.     

Malignant fibrous histiocytoma,giant cell type,of the breast mimicking metaplastic carcinoma. A case report

BACKGROUND: We report a case of malignant fibrous histiocytoma, giant cell type (MFHGC), of the breast. A review of the literature failed to reveal cytology-based reports on this entity. The cytologic similarity of breast MFHGC on fine needle aspiration biopsy (FNAB) to other malignant breast neoplasms, including carcinoma with osteoclastlike giant cells, metaplastic carcinoma and breast sarcomas, as well as benign reactive processes, makes the recognition of this tumor challenging. CASE: A 72-year-old woman presented with a 5-month history of an enlarging breast mass. FNAB of the mass showed a hypercellular smear composed of cohesive, branching clusters of spindle cells with ovoid, focally hyperchromatic nuclei and inconspicuous nucleoli. Interspersed osteoclastlike giant cells, some associated with clusters of spindle cells, were uniformly seen throughout the smear. The background was hemorrhagic, with cellular debris and occasional spindle cells and lymphocytes. No ductal epithelial or myoepithelial cells were seen. An incisional biopsy was performed, followed by radical mastectomy. The histologic examination was diagnostic of MFHGC. The diagnosis was supported by immunohistochemical and electron microscopic studies. CONCLUSION: MFHGC, also called primary giant cell tumor of soft tissues, is composed of a mixture of histiocytes, fibroblasts and bland-appearing osteoclastlike giant cells with a multinodular growth pattern. Although MFHGC rarely occurs in the breast and the definitive diagnosis is difficult based on cytology alone, the diagnosis can be considered when a cytologic examination reveals a hypercellular, spindle cell smear with osteoclastlike giant cells in the absence of ductal epithelial or myoepithelial cells.     

Low grade fibromyxoid sarcoma: report of a case with fine needle aspiration cytology and histologic correlation

BACKGROUND: Low grade fibromyxoid sarcoma has been fully described histologically; however, the fine needle aspiration (FNA) cytologic findings are scantily defined, and the distinction from other benign and malignant soft tissue tumors can be difficult. CASE: We examined FNA cytologic material from a slowly growing, large chest wall mass in a 28-year-old woman. The surgical specimen was processed for routine histology and immunohistochemical studies. The cytologic smears were adequately cellular, showing spindly cells with uniform, elongated nuclei; small, inconspicuous nucleoli; and scanty, wispy cytoplasm associated with myxoid material. No significant nuclear pleomorphism or mitoses were noted. The excised tumor was well circumscribed, focally infiltrating the surrounding muscles. The cut surface was variable, featuring fibrous, solid, fleshy and myxoid areas. Microscopically, the solid, fibrous areas displayed increased cellularity with storiform, intersecting and parallel patterns. In the myxoid areas the cells grew in a haphazard fashion and appeared floating in abundant mucoid matrix associated with a capillary vascular network similar to the chicken-wire pattern seen in cases of myxoid liposarcoma. The tumor cells were spindly, with fusiform, uniform nuclei. Focal, moderate nuclear pleomorphism was noted. The mitotic index was low. The tumor cells were positive for vimentin, alpha-1-antitrypsin and lysozyme and negative for S-100, actin, desmin and CD34. CONCLUSION: Although low grade fibromyxoid sarcoma is a rare neoplasm, it should be recognized and distinguished from other soft tissue tumors because of its low malignant potential. The definitive FNA cytologic diagnosis can be challenging but is possible if the tumor is adequately sampled, with multiple passes from different areas. Clinical and radiologic correlations are of great help. All spindle cell tumors with myxoid changes, such as myxoid liposarcoma, myxofibrosarcoma, cellular myxoma, myxoid leiomyosarcoma and peripheral nerve sheath tumors, should be considered in the differential diagnosis. In contrast to the cytologic features, the histologic findings are characteristic and well established.     

Logistic regression analysis of low grade spindle cell lesions. A cytologic study

OBJECTIVE: To identify key diagnostic cytologic criteria for various low grade spindle cell lesions. STUDY DESIGN: We reviewed 20 synovial sarcomas, 18 benign neural tumors, 10 reparative lesions, 24 other benign and 27 additional malignant low grade spindle cell lesions. All specimens were coded as to the presence or absence of the following variables: high cellularity, tissue fragments, tissue culture appearance, epithelial fragments, vessel fragments, vascular arcades, fibrillar ground substance, myxoid background, microcystic areas, parallel arrangement of nuclei, naked nuclei, single cells, binucleate cells, multinucleate cells, long filamentous cells, short spindle cells, stellate cells, lipoblasts, nuclear pleomorphism, nuclei with pointed ends, comma/fishhook nuclei, cigar-shaped nuclei, ovoid/round nuclei, small nucleoli, large nucleoli, mitotic figures, intranuclear vacuoles and background histiocytes. A logistic regression analysis was performed to identify the variables predictive of malignant lesions, specifically synovial sarcomas, benign neural tumors and reparative lesions. RESULTS: Statistical analysis selected high cellularity, short spindle cells, small nucleoli and absence of tissue culture appearance as the main criteria for malignant neoplasms. Tissue fragments and high cellularity were selected as the primary criteria and absence of long filamentous cells and of myxoid background as the secondary criteria for synovial sarcomas. It selected fibrillar ground substance and absence of ovoid/round nuclei as the key criteria for benign neural tumors. The presence of a tissue culture appearance was the major criterion for reparative lesions. CONCLUSION: There are many previously described cytologic criteria, but we found that when subjected to statistical analysis, only a few features were significant in the evaluation of low grade spindle cell lesions.     

Highly well differentiated hepatocellular carcinoma and benign hepatocellular lesions. Can they be distinguished on fine needle aspiration biopsy?

OBJECTIVE: To determine whether highly well differentiated hepatocellular carcinoma can be distinguished from benign hepatocellular lesions on fine needle aspiration biopsy (FNAB). STUDY DESIGN: Ninety-five FNABs from 88 patients with hepatic masses/diffuse conditions were reviewed according to new cytologic criteria established by Takenaka et al. They were classified into well-, moderately and poorly differentiated hepatocellular carcinomas (W-, M- and P-HCC) and benign aspirates and histologically verified. RESULTS: There were 21 W-HCC, 39 M-HCC, 10 P-HCC, 3 problematic and 22 benign aspirates. The most useful criteria for diagnosing highly W-HCC were architectural features on the smears/cell block sections, including hypercellularity; arborescent, cohesive clusters; broad trabeculae; transgressing and peripheral endothelium; and cytologic details of small, monotonous hepatocytes with nuclear crowding, decreased cytoplasm, increased nuclear/cytoplasmic ratio, atypical naked nuclei and tumor giant cells. Well-defined cytoplasmic borders, abundant thick and monotonous cytoplasm, eccentric nuclei, thick nuclear membranes, irregular nuclear contours, increased chromatin density, irregular chromatin distribution and macronucleoli were not always detectable in highly W-HCC. In fact, some of them were seen in dysplastic hepatocytes. Deficient reticulin patterns and diffuse sinusoidal CD34 reactivity were helpful. CONCLUSION: Experience, attention to architectural and cytologic details in smears/cell blocks and clinicopathologic correlation should reduce the number of indeterminate reports. However, there will always remain some cytohistologically challenging cases.     

Malignant melanoma of the cervix. Report of a case

A malignant melanoma of the cervix, a rare neoplasm, was found to have an unusual cytologic pattern, similar to that of a leiomyosarcoma. A biopsy sample was diagnosed as cervical malignant melanoma of the spindle cell type. Some neoplastic cells in the tissue contained melanin pigment, whereas none of the abnormal cells in the cervical scrapes, except for an abnormal giant cell, had visible cytoplasmic pigment. The abnormal cells in the cervical scrape specimen were spindle-shaped, as were their nuclei, which is why the cytologic pattern was interpreted as that of a leiomyosarcoma. Evidence from this and previously reported cases shows that malignant melanoma must be considered as a possible source of exfoliated abnormal nonpigmented spindle-shaped cells in a cervicovaginal cell sample.     

Cytomorphology of subependymal giant cell astrocytoma.

The cytomorphology of three subependymal giant cell astrocytomas (SEGA) is described. The tumors occurred in the left lateral ventricle of three males with tuberous sclerosis. The often-polarized spindle and epithelioid tumor cells possessed dense eosinophilic cytoplasm, eccentric nuclei and visible, occasionally prominent nucleoli. In addition, they displayed thick or hairlike processes and had a distinct tendency to form cohesive clusters as well as pseudorosettes. Occasional binucleate and multinucleate cells, as well as "strap" cells and nuclear cytoplasmic inclusions, were further features of this unique tumor. In cytologic terms the principal differential diagnostic considerations include gemistocytic astrocytoma, giant cell glioblastoma and ependymoma. Since, in isolation, SEGA may represent a "forme fruste" of tuberous sclerosis and since patients with tuberous sclerosis may have brain tumors other than SEGA, it is of diagnostic importance to recognize the cytomorphologic features of this essentially benign brain tumor.     

Fine needle aspiration cytology of apocrine carcinoma of the breast. Review of cases in a three-year period

OBJECTIVE: To describe the fine needle aspiration cytology findings of apocrine carcinoma of breast and correlate them with the histologic appearance. STUDY DESIGN: The author reviewed the fine needle aspiration cytology findings of two cases of pure apocrine carcinoma of the breast in the files of Pamela Youde Nethersole Eastern Hospital during a three-year period, 1998-2000. RESULTS: The cytologic findings in both cases were similar. The smears were of moderate to high cellularity, consisting of predominantly dispersed or loosely cohesive tumor cells in a focally granular background. The carcinoma cells contained abundant, dense to granular cytoplasm; round or oval and sometimes eccentrically located nuclei; a smooth nuclear outline; evenly dispersed chromatin; and solitary macronucleoli. The cell borders were mostly discrete. In contrast to benign apocrine cells, the malignant cells showed nuclear overlapping, more frequent nuclear pleomorphism, increased nuclear/cytoplasmic ratios and occasional mitotic figures. Histologic examination of the excised specimens showed extensive, solid apocrine carcinoma in situ with focal stromal invasion. CONCLUSION: Apocrine carcinoma, a subtype of breast carcinoma characterized mainly by its cytologic features, needs to be distinguished from benign apocrine lesions or other eosinophilic and granular cell tumors of the breast. Recognition of the subtle cytologic differences renders a definitive preoperative diagnosis possible.     

Logistic regression analysis of high grade spindle cell neoplasms. A fine needle aspiration cytologic study.

OBJECTIVE: To identify primary diagnostic cytologic criteria for various high grade spindle cell neoplasms. STUDY DESIGN: We reviewed 30 osteosarcomas, 29 malignant fibrous histiocytomas (MFH), 26 malignant melanomas, 13 chondrosarcomas, 12 leiomyosarcomas, 7 angiosarcomas and 5 liposarcomas. All specimens were coded as to the presence or absence of the following variables: high or low cellularity, tissuelike fragments, glandlike fragments, single cells, binucleated cells, multinucleated cells, lipoblastlike cells, histiocytelike cells, fibroblastlike cells, signet-ring cells, short spindle cells, long filamentous cells, stellate cells, osteoclastic giant cells, malignant giant cells, background cells, pointed nuclei, cigar-shaped nuclei, fishhook-shaped nuclei, round or ovoid nuclei, intranuclear vacuoles, macronucleoli, small nucleoli, mitotic figures, abnormal mitotic figures, pleomorphism, nuclear/cytoplasmic ratio (mild, moderate, marked increase), amount of cytoplasm (scant, moderate, abundant), fine or coarse granular cytoplasm, intracytoplasmic hemosiderin deposits, melanin, cytoplasmic vacuoles, fat, capillary vessel fragments, storiform pattern, necrosis, large or small amount of myxoid material, filamentous stroma, dense collagenous stroma, osteoid, chondroid and cells in lacunae. A logistic regression analysis was performed to identify the variables predictive of each diagnostic category. RESULTS: The statistical analysis selected positive expression of osteoid, osteoclastic giant cells and low cellularity as the primary criteria associated with osteosarcomas. Positive expression of fibroblastlike cells, large amount of myxoid material and multinucleated cells were identified to be the key criteria for MFH. The analysis selected the presence of melanin as the major criterion for malignant melanomas, cells lying in lacunae for chondrosarcomas, fishhook nuclei for leiomyosarcomas, intracytoplasmic iron deposits for angiosarcomas and lipoblastlike cells for liposarcomas. CONCLUSION: From the previously described cytologic criteria, statistical analysis helped identify several key features that are significant in the evaluation of pleomorphic spindle cell neoplasms.     

Fine needle aspiration cytology of intranodal myofibroblastoma. A case report

BACKGROUND: Intranodal myofibroblastoma is a rare, primitive, mesenchymal neoplasm of the lymph nodes first described in 1989. It behaves in a benign fashion and has a great predilection for the inguinal region. CASE REPORT: A 56-year-old man was referred for fine needle aspiration cytology of an inguinal lymph node. Smears were moderately cellular, with a predominant population of single, small spindle cells with no atypia. Most neoplastic cells were distributed as dissociated, single cells, with few groups. The cells showed metachromatic stromal material with a fibrillary quality. Nuclei were elongated, with pointed ends and occasional twisted forms. A remarkable finding on Papanicolaou-stained smears was hemosiderin granules. After a cytologic report of low grade spindle cell tumor, the node was excised, and a histologic and immunohistochemical diagnosis of intranodal myofibroblastoma was established. CONCLUSION: Intranodal myofibroblastoma should always be considered when aspirating solitary inguinal lymph nodes. The presence of a low grade spindle cell pattern of variably dissociated cells with hemosiderin granules should lead to immunocytochemical studies. Muscle-specific actin expression in the absence of S-100 protein and vascular markers permits a more specific diagnosis.     

Cytology of primary cutaneous Langerhans cell histiocytosis with a malignant phenotype. A case report

BACKGROUND: Langerhans cell histiocytosis (LCH) is a proliferative disorder of Langerhans cells, but the nature of LCH, whether reactive, benign, or malignant and neoplastic, is controversial. We encountered a case of LCH showing a malignant phenotype initially localized in the skin of an elderly woman. Since there is no other report on the cytologic appearance of primary cutaneous LCH or on LCH with a malignant phenotype, we compared the cytologic features of this case with those of benign cases at other sites reported in the literature. CASE: A 74-year-old woman presented with a gradually enlarging and partially ulcerated skin lesion expanding both sides of her right hand. On histologic and ultrastructural analyses of surgically resected tissue, we diagnosed the lesion as Langerhans cell histiocytosis originating in the skin. Although the patient had no recurrence or metastases for six months after surgical resection of the primary skin lesion and radiation therapy, the tumor extended multisystemically, and the patient died of multiple organ failure 14 months after the initial diagnosis. CONCLUSION: Imprint and scrape cytology of multiple skin lesions six months after surgery was useful in immediately diagnosing the recurrent LCH. The tumor cells had indented, twisted or grooved nuclei, and some had intranuclear inclusions. Immunocytochemically the cells were positive for CD1a and S-100 protein. Numerous eosinophils were seen in the background.     

Liquid-based cytology findings of glassy cell carcinoma of the cervix. Report of a case with histologic correlation and molecular analysis

BACKGROUND: Glassy cell carcinoma is a rare form of poorly differentiated carcinoma of the cervix with no obvious squamous or glandular differentiation. Its liquid-based cytology findings have not been described before. CASE: A 46-year-old Filipina presented with vaginal bleeding due to a bulky cervical tumor. The liquid-based cytology preparation was of moderate cellularity and contained small clusters of polygonal to elongated tumor cells admixed with amphophilic, granular, necrotic debris. The malignant cells possessed round to oval nuclei; a thin nuclear membrane; finely dispersed chromatin; prominent, solitary nucleoli; abundant, cyanophilic cytoplasm; and discrete cell borders. Occasional tumor cells showed phagocytosis of polymorphs. The background contained a mixed population of inflammatory cells. Eosinophils, though present, were not readily identified in the cytologic specimen. There was no evidence of dyskeratosis, cytoplasmic vacuolation or koilocytosis. Histologic and ultrastructural examination of the tumor biopsy showed classic features of glassy cell carcinoma. Molecular analysis using polymerase chain reaction and restriction fragment length polymorphism revealed the presence of human papillomavirus (HPV) DNA in the liquid-based cytology sample. The HPV genotype, however, did not belong to any of the commonly encountered prototypes. CONCLUSION: Glassy cell carcinoma of the cervix may show distinct, though subtle, cytomorphologic features in liquid-based preparations. The findings, however, are slightly different from those in conventional cervical smears. Awareness of this rare entity is important, as glassy cell carcinoma is often associated with more aggressive clinical behavior.     

Imprint cytologic features of intracytoplasmic lumina in ependymoma. A report of two cases

BACKGROUND: Intracytoplasmic lumina have been recently recognized as a characteristic histologic feature of ependymoma. However, the cytologic diagnostic usefulness has not been discussed. We encountered two imprint cytology cases of spinal cord ependymomas in which there were intracytoplasmic lumina in the tumor cells. CASES: Two women had spinal cord tumors on magnetic resonance imaging. Imprint cytology study was carried out on the resected tumors. The cytologic specimen of the first case, aged 52, showed tumor clusters consisting of elongated epithelioid cells, a few of which also had intracytoplasmic lumina. Histologically, tumor cells formed ependymal rosettes and pseudoperivascular rosettes. There were a few tumor cells with intracytoplasmic lumina. The cytologic specimen of the second patient, aged 37, had scattered and isolated tumor cells with intracytoplasmic lumina resembling signet-ring cells and paired tumor cells forming small, glandlike structures. Histologically, the tumor was composed mainly of signet-ring-like cells containing intracytoplasmic lumina. CONCLUSION: Intracytoplasmic lumina were observed in the imprint cytologic specimens of spinal cord ependymoma. The diagnosis of ependymomas can be made cytologically when intracytoplasmic lumina are found since no other primary neuroepithelial tumors of the central nervous system possess such a characteristic feature.     

Immunohistochemical studies on the tissue localization of collagen types I, III, IV, V and VI in schwannomas. Correlation with ultrastructural features of the extracellular matrix

The distinctive tissue localization of collagen types in typical schwannomas with Antoni type A and B areas was demonstrated immunohistochemically using affinity-purified antibodies against types I, III, IV, V and VI collagen and comparative ultrastructural studies were made on the extracellular matrix components. Antoni type A tissue, which was composed of tightly packed spindle cells with long cytoplasmic processes surrounded by a continuous basement membrane and a few fibrillar components of the extracellular matrix, was almost exclusively immunoreactive for type IV collagen, presumably representing the basement membrane. Verocay bodies, which are organoid structures of Antoni type A tissue, had a variety of more abundant extracellular fibrous components, such as banded collagen fibrils, fibrous long-spacing fibrils and microfibrils. These were positive for type I and III, as well as type IV collagen. In Antoni type B areas, where two types to tumor cells designated Schwann cell-like and fibroblast-like were scattered in large amounts of amorphous extracellular matrix containing microfibrils and thick banded collagen fibrils, type VI collagen as well as types I, III and IV collagen were consistently detected. Type V collagen was localized in dense fibrous tissue areas and around blood vessels. These findings indicate that the differently organized cellular patterns of schwannomas, identified as Antoni types A and B, are characterized not only by the ultrastructural features of the extracellular matrix, but also by the distinctive collagen types produced by neoplastic Schwann cells.     

Solitary fibrous tumor of the kidney: a case report and review of the literature

A solitary fibrous tumor (SFT) is an unusual spindle cell neoplasm that usually occurs in the pleura but has recently been described in diverse extrapleural sites. Urogenital localization is rare, and only 19 cases of SFT of the kidney have been described. We report a case of a large SFT clinically thought to be renal cell carcinoma arising in the kidney of a 70-year-old man. The tumor was well circumscribed and composed of a mixture of spindle cells and dense collagenous bands, with areas of necrosis or cystic changes noted macroscopically and microscopically. Immunohistochemical studies revealed reactivity for CD34, CD99, and Bcl-2 protein, with no staining for keratin, S-100 protein, or muscle markers, confirming the diagnosis of SFT. This tumor is benign in up to 90% of cases. The immunohistochemical study is the key to diagnosis.