Benign Spindle Cell Tumor Research Articles

Myopericytoma: A Pleural-Based Spindle Cell Neoplasm Off the Beaten Path

Myopericytoma is a recently described hemangiopericytoma-like neoplasm with myoid differentiation. These tumors are typically located in the subcutaneous and soft tissues of the extremities. The authors report a rare pleural-based pulmonary myopericytoma in a 58-year-old woman. The lesion was grossly homogeneous and well circumscribed. Microscopically, it was composed of densely packed spindle cells organized as whorls and short interlacing fascicles with a concentric perivascular distribution. Immunohistochemical reactions were positive for vimentin, smooth muscle actin (SMA), muscle-specific actin, and Bcl-2 and negative for desmin, h-caldesmon, cytokeratin, and CD34. Atypically, increased mitotic activity was noted, but no other malignant features were identified. The differential diagnoses are discussed with specific emphasis on solitary fibrous tumor of the pleura, which is the most common benign pleural-based spindle cell neoplasm and may be a diagnostic pitfall with potentially harmful consequences.

Myofibroblastoma of the Female Breast

Myofibroblastoma (MFB) of the breast was coined by Wargotz et al 1 in 1987 to describe benign spindle cell tumors of the breast with myofibroblastic features. There has been only 1 report about mammographic and sonographic findings of MFB of the female breast. 2 We report a case of a pathologically diagnosed breast MFB in a female patient and describe the imaging characteristics, including mammography, sonography, and magnetic resonance imaging (MRI). We also discuss other breast diseases that can be included in the differential diagnosis with MFB from a radiologic point of view.

Cutaneous leiomyosarcoma originating in a symplastic pilar leiomyoma: a rare occurrence and potential diagnostic pitfall

A case of cutaneous leiomyosarcoma originating in a symplastic pilar leiomyoma is described. The patient was a 60-year-old man who presented with a painless nodule on his chest. Thorough clinical examination did not reveal any evidence of tumor elsewhere. A punch biopsy was performed which showed a benign spindle cell neoplasm with focal cellular pleomorphism that had smooth muscle differentiation and was clearly originating from the arrector pili muscle, consistent with a cutaneous symplastic pilar leiomyoma. Immunohistochemical studies were performed and the tumor cells were strongly positive for smooth muscle actin (SMA) and desmin. Given the clinical information of a mass on the chest, clinical evaluation was recommended and a re-excision was performed. Histologically, the re-excision showed two distinct populations of cells. The upper portion of the tumor mirrored the initial biopsy; however, the base of the tumor showed hypercellular areas composed of spindle cells with marked pleomorphism and increased number of mitoses. The diagnosis of a cutaneous leiomyosarcoma originating in a symplastic pilar leiomyoma was given. This is the first report of this association of such occurrence reported in the literature.

Lipomatous variant of myofibroblastoma with epithelioid features: a rare and diagnostically challenging breast lesion

Myofibroblastoma of the breast is an unusual benign spindle cell tumor composed of cells with histologic, immunohistochemical, and ultrastructural features of myofibroblasts. In addition to the classic form, a few variants of myofibroblastoma have been described. Recognition of these variants is important to prevent overdiagnosis of a malignant lesion, especially on core biopsy. Three variants that can cause particular confusion on core biopsy are the lipomatous, infiltrative, and epithelioid variants of myofibroblastoma. Thus far, there have been only a few reports of these variants in the English literature. We report a rare case of a lipomatous variant of myofibroblastoma with an epithelioid cell component and discuss the differential diagnosis and potential diagnostic pitfalls.

Clinico-pathological features of breast myxoma: report of a case with histogenetic considerations

We herein report the clinical, radiological, and pathological findings of a rare case of myxoma occurring in the breast parenchyma of a 75-year-old female. The tumor was incidentally detected at a mammographic screening and, ultrasonographically, presented as an ovoid mass. Histologically, an encapsulated hypocellular, myxoid tumor with low vascularization was evident. Neoplastic cells were round- to spindle/stellate-shaped and stained with vimentin and focally with calponin. We emphasize that morphology remains preeminent in the diagnosis of a breast myxoma, while immunohistochemistry may assist in ruling out other tumor entities. Differential diagnosis with all benign and malignant myxoid lesions, primarily occurring in the breast, is provided. The histogenesis of breast myxoma is unknown. The lack of expression of desmin, alpha-smooth muscle actin, CD34, CD99, CD10, bcl-2 protein, and estrogen/progesterone/androgen receptors, all markers characteristically expressed by "the benign spindle cell tumors of the mammary stroma," would suggest that breast myxoma does not fall into this tumor category and that its putative precursor mesenchymal cell resides in the interlobular stroma.

Extraconal orbital tumors in children—a spectrum

Orbital masses in children are uncommon but extremely challenging problems for clinicians and pathologists due to their critical location and availability of limited diagnostic material. We analyzed 47 specimens comprising biopsies, excision specimens, and FNAC of extraconal pediatric orbital masses (excluding retinoblastoma) accessioned in the pathology department over 5 years in a tertiary referral cancer center. Immunohistochemistry (IHC-74%) and molecular methods (one case) were done where necessary. The chief presenting symptom was proptosis in 55.3% patients and radiologically 53.8% malignant tumors showed extraorbital extension. A diagnostic algorithm was formulated to assess which cases needed pathology evaluation. Malignant round cell tumors (76.6%), chiefly embryonal rhabdomyosarcoma (51%), benign spindle cell neoplasms, and infectious lesions (tuberculosis, fungal infections), were seen. Of the malignant tumors, those confined to the orbit achieved good treatment response and had an event-free follow-up while those with extraorbital spread had poor outcome. Pediatric orbital masses range from completely treatable infectious lesions, surgically resectable benign neoplasms to aggressive malignancies requiring chemotherapy and radiotherapy. Pathologists play a key role in distinguishing these on small biopsy material and expediating accurate treatment thus saving the vision or life of a patient.

LOSS OF EXPRESSION OF THE VITAMIN D RECEPTOR IN CLEAR CELL RENAL CELL CARCINOMA

biopsy yielding 91 specimens. Three patients had 2 masses and three more patients underwent rebiopsy. A definitive diagnosis was established in 76 patients (89%). Of the 91 specimens 22 (24%) were benign including 11 oncocytomas, 7 lipid poor angiomyolipomas, 2 abscess/ pyelitis, 1 metanephric adenoma, and 1 benign spindle cell neoplasm. 20 patients (24%) had minor complications including 14 small perinephric hematomas (none required transfusion or admission to the inpatient ward), 2 difficulty voiding, 1 small pneumothorax, 1 rash, 1 shoulder pain, and 1 generalized musculoskeletal pain. The biopsy changed management in 22 patients (26%) with benign lesions or metastatic disease from another primary. Of the remaining 63 patients 24 underwent partial or radical nephrectomy. In all these patients the final pathology of these tumors confirmed the malignant diagnosis derived from biopsy. The remainder of the patients elected needle ablation or observation. CONCLUSIONS: CT guided biopsy of a small solid renal mass is a safe procedure that provides diagnostic information about 90% of the time. Biopsy provides clinically useful information by identification of benign lesions and confirmation of type and grade of malignancy if either resection of needle ablative therapy is a consideration.

Fine Needle Aspiration Cytology of Schwannoma of the Parotid Gland

This 52-year-old male underwent fine needle aspiration biopsy of a 2cm diameter parotid mass that was firm, well-delineated, and vaguely moveable, The mass was not painful and was noted for about a year.  The aspiration biopsy smear was quite cellular and showed fragments of spindle-shaped cells with cigar shaped nuclei and scanty to indistinct cytoplasms.  Nuclei were vesicular and Verocay-like bodies were identified by cell patterns.  The biopsy was read as a benign spindle cell tumor, probably a schwannoma.   Excision of the mass revealed a typical schwannoma by histopathology. Schwannomas of the parotid gland are rare1 and arise from the intraparotid branches of the facial nerve.   Clues to the cytologic diagnosis include the cellular but benign spindly cell population clustered into Verocay body patterns and evidence of cyst degeneration in the form of histiocytes and even lymphocytes.2 Main differential diagnoses include the predominant spindle cell myoepitheliomas3 and some of the low grade sarcomas that may arise from the parotid gland.   The even rarer schwannomalike mixed tumor of the parotid4 gland must be also considered.

Tanycytic ependymoma: two case reports and review of the literature

Two cases of tanycytic ependymoma are reported, one in a woman aged 33 years and one in a man aged 36 years. The woman presented with lesions at L2 and L3 in the spinal cord and clinical symptoms suggested spinal cord compression, such as movement and sensory dysfunction. The man had a lesion located in the lateral ventricle and presented with headache, vomiting, and impaired vision. Both of these patients developed gradual increases in the intensity of their symptoms over a few months prior to admission. A spinal cord MRI of the woman showed a well-defined, solid cystic mass measuring 1.0 × 6.5 cm at L2 and L3 of the spinal cord. The mass showed low signal intensity on T2-weighted images in the intervertebral disc with equal signal intensity T1-/T2-weighted images. The signal was uniform and enhanced scanning showed a light strengthening of signal. A brain MRI of the man showed a well-defined mass measuring 4 cm in diameter invading the right ventricle. The mass showed low signal intensity on right T1-weighted images and high signal intensity on T2-weighted images. Histopathologically, the tumors were rich with significant and uniform proliferation of long spindle cells, which were arranged in fasciculate and knitted patterns with bipolar and spindled processes focally forming perivascular pseudorosettes. The cell nuclei showed minor pleomorphism. A few tumor cells centered on the vessels resulted in a nuclear-free zone, which was characteristic of ependymoma. Immunohistochemically, the tumor cells were positive for GFAP, EMA, and CD99, but negative for S-100. A review of the cases reported in the literature shows that tanycytic ependymoma occurs more often in the spinal cord. As it can resemble pilocytic astrocytoma and schwannoma, tanycytic ependymoma should be differentially diagnosed to exclude some of the benign spindle cell tumors of the central nervous system.

Schwannoma Arising in a Lymph Node - A Brief Case Report -

Intranodal schwannomas are extremely rare and only three cases have currently been reported in the English language literature. We report here on a case of a schwannoma that arose in a retroperitoneal lymph node. A 59-year-old male patient had experienced abdominal discomfort for two months. An abdominal CT scan demonstrated a heterogeneous density mass in the retroperitoneum. Histological examination of the mass identified it as a lymph node due to the presence of a peripheral rim of compressed lymphoid tissue that contained a well-demarcated benign spindle cell tumor in its center. The spindle cells were positive for S-100 protein, and they were negative for smooth muscle actin, desmin, and CD 34. Although an intranodal schwannoma is histologically benign, it is important to distinguish this lesion from an intranodal metastasis of a spindle cell tumor and other common benign spindle cell tumors that can arise in a lymph node.

An Unusual Case of Intraparotid Facial Nerve Schwannoma

An Unusual Case of Intraparotid Facial Nerve Schwannoma

Fine Needle Aspiration Cytology of Schwannoma of The Parotid Gland

This 52-year-old male underwent fine needle aspiration biopsy of a 2cm diameter parotid mass that was firm, well-delineated, and vaguely moveable,
 The mass was not painful and was noted for about a year. The aspiration biopsy smear was quite cellular and showed fragments of spindle-shaped cells with cigar shaped nuclei and scanty to indistinct cytoplasms. Nuclei were vesicular and Verocay-like bodies were identified by cell patterns. The biopsy was read as a benign spindle cell tumor, probably a schwannoma. 
 Excision of the mass revealed a typical schwannoma by histopathology.
 Schwannomas of the parotid gland are rare1 and arise from the intraparotid branches of the facial nerve. Clues to the cytologic diagnosis include the cellular but benign spindly cell population clustered into Verocay body patterns and evidence of cyst degeneration in the form of histiocytes and even lymphocytes.2 Main differential diagnoses include the predominant spindle cell myoepitheliomas3 and some of the low grade sarcomas that may arise from the parotid gland. The even rarer schwannomalike mixed tumor of the parotid4 gland must be also considered.

Mammary myofibroblastoma: a tumor with a wide morphologic spectrum.

Abstract Context.—Myofibroblastoma (MFB) of the breast is an unusual benign tumor that belongs to the family of the “benign spindle cell tumors of the mammary stroma.” The name MFB reflects its cellular composition, comprising mainly stromal cells with fibromyofibroblastic and, less frequently, myoid differentiation. Since the original description, the morphologic spectrum of MFB has been expanded by the recognition of several unusual morphologic variants, such as the cellular, infiltrative, epithelioid, deciduoid-like, lipomatous, collagenized/fibrous, and myxoid variants. Objective.—To review the literature on mammary MFB, discussing the main clinical, radiologic, and pathologic features helpful for diagnosis. Since MFB may show alarming morphologic features, which can lead to a misdiagnosis of malignancy, histologic figures of this tumor, including its more unusual variants, are provided to offer pathologists a practical approach to a correct diagnosis. Histogenesis and pathogenesis of this tumor are a...

Mammary Myofibroblastoma: A Tumor With a Wide Morphologic Spectrum

Myofibroblastoma (MFB) of the breast is an unusual benign tumor that belongs to the family of the "benign spindle cell tumors of the mammary stroma." The name MFB reflects its cellular composition, comprising mainly stromal cells with fibromyofibroblastic and, less frequently, myoid differentiation. Since the original description, the morphologic spectrum of MFB has been expanded by the recognition of several unusual morphologic variants, such as the cellular, infiltrative, epithelioid, deciduoid-like, lipomatous, collagenized/fibrous, and myxoid variants. To review the literature on mammary MFB, discussing the main clinical, radiologic, and pathologic features helpful for diagnosis. Since MFB may show alarming morphologic features, which can lead to a misdiagnosis of malignancy, histologic figures of this tumor, including its more unusual variants, are provided to offer pathologists a practical approach to a correct diagnosis. Histogenesis and pathogenesis of this tumor are also proposed. Clinicopathologic data on MFB were extracted from all identified articles through PUB Medline- based research. Histologic figures have been taken from the personal archive of the author. The incidence of MFB diagnosis has increased in recent years, likely due to the mammographic screening. Accordingly, this unusual benign tumor may represent a potential diagnostic pitfall, especially when interpreting fine-needle aspiration and/or needle core biopsy. Pathologists should be aware of the wide morphologic spectrum exhibited by MFB to avoid a misdiagnosis of malignancy.

Phosphaturic mesenchymal tumor diagnosed by fine‐needle aspiration and core biopsy: A case report and review of literature

Oncogenic (tumor-induced) osteomalacia is a rare paraneoplastic syndrome of phosphate wasting that is frequently associated with phosphaturic mesenchymal tumor (PMT). As the cytologic features of this tumor apparently have not been reported, we describe the fine-needle aspiration (FNA) findings for PMT that arose from the gluteal soft tissue in a patient with hypophosphatemia and multiple fractures secondary to osteomalacia. Smears from the computerized tomography (CT)-guided FNA showed groups of spindle cells having elongated nuclei, fine to moderately coarsely granular chromatin, inconspicuous nucleoli, and delicate cytoplasm. Marked nuclear atypia, mitotic figures, and necrosis were absent. The differential diagnosis included a variety of benign and malignant spindle cell neoplasms such as monophasic synovial sarcoma, leiomyoma, peripheral nerve sheath tumor, fibrosarcoma, and, less likely, metastatic melanoma and sarcomatoid carcinoma. The bland-appearing cytologic features of a spindle cell tumor in a patient with osteomalacia should suggest the diagnosis of PMT.

Incidental Finding during Venous Duplex Examination: Solitary Fibrous Tumor or Arteriovenous Malformation in the Left Lower Extremity

Purpose —Superficial varicosities surrounding a palpable mass in the posterior aspect of the left thigh were investigated during a venous duplex examination. A well-defined mass with arterial and venous feeding branches strongly suggested the presence of an arteriovenous malformation. We present an unusual case of a soft-tissue thigh mass that appeared to be an arteriovenous malformation by ultrasound and arteriography but after surgical resection was confirmed to be a benign soft tissue tumor. Case Report —A 32-year old woman presented with superficial varicosities surrounding a painful mass on the posterior aspect of her left thigh. Venous duplex exam demonstrated normal findings of the deep veins, but further investigation of the superficial varicosities revealed a 3.5-cm x 6.0-cm soft-homogenous mass with a large complex network of arterial and venous feeding branches. Arteriography confirmed a well-defined thigh mass with an arterial network feeding the mass. Surgical resection of this well-circumscribed mass was performed. Histological tissue exam revealed a benign low-grade spindle cell neoplasm with blood vessels. Conclusion —This report highlights the importance of evaluating all abnormal superficial varicosities and palpable soft-tissue masses as part of a lower extremity vascular duplex evaluation because incidental findings not diagnosed through clinical examination may be detected.

Giant cell angiofibroma of the orbit with periosteal adherence

We report a case of orbital giant cell angiofibroma, an unusual, recently reported benign spindle cell neoplasm. Preoperative clinical assessment and radiology suggested a benign mass and early operative findings were in concordance with this. Surgical excision was however, hampered by periosteal adhesion and lack of distinct encapsulation in the posterior part of the lesion. The histology of giant cell angiofibroma and its principle pathological differential diagnoses is discussed. As with some lymphangiomas, this is another benign orbital tumour which may present difficulties in complete surgical excision that are not anticipated based on the preoperative findings.

Biphasic parapharyngeal synovial sarcoma : A cytologic and immunocytologic report of a case

BackgroundSynovial sarcoma is a rare soft tissue sarcoma in the head and neck region and parapharyngeal space. There is no previous cytologic report of synovial sarcoma of parapharynx. The cytologic and immunocytochemical findings of a parapharyngeal biphasic synovial sarcoma together with diagnostic pitfalls are described.Case reportA 21-year-old girl presented with a 6-month history of progressive right arm pain, neck mass and upper aerodigestive tract obstruction. On physical examination there was a large painless mass arising from the right-sided parapharyngeal space causing airway obstruction. Initial magnetic resonance imaging (MRI) revealed a large tumor in the right-sided parapharyngeal space. Fine needle aspiration through cervical region was performed and was reported as benign spindle cell tumor. Smears were cellular and composed mostly of tight and loose clusters of spindle cells. Epitheloid cells could also be identified intermingled with them. She underwent near total resection of the tumor. Pathologic report disclosed the diagnosis of synovial sarcoma. She then received postoperative adjuvant external radiotherapy.ConclusionDue to rarity of this tumor in this region and nonspecific cytologic features, we could not differentiate this tumor from the other more common spindle cell neoplasms. Considering synovial sarcoma in this region and immunocytochemistry can be helpful in rendering a correct initial diagnosis of this tumor.

Histiocytoma cutis: a tumour of dermal dendrocytes (dermal dendrocytoma)

The histogenesis of histiocytoma (dermatofibroma) was investigated using new antibodies that demonstrate factor XIIIa (FXIIIa) positive cells and the monocyte macrophage cell series (MAC 387), in formalin fixed tissue. The distribution of S100 protein, vimentin and Ulex europaeus agglutinin I (UEA-I) were also studied. The antibody against FXIIIa labelled the normal dermal population of fixed connective tissue cells (dermal dendrocytes) emphasizing their dendritic processes; cells that are widely distributed, but are most numerous in the papillary dermis. In contrast, the antibody, MAC 387 against monocyte derived macrophages, did not label this cell population. In 30 histiocytomas, intense labelling for FXIIIa was found peripherally, but labelling was rather weaker in cells situated centrally. Only a few cells labelled for S100 protein and with the monoclonal antibody MAC 387, but vimentin positivity was universal. UEA-I labelled only vessels in histiocytomas. However, FXIIIa labelling was negative in 16 dermatofibrosarcomas, three keloids and several other fibroproliferative lesions. These contrasting results with FXIIIa labelling have practical implications for diagnosis of benign and malignant spindle cell tumours of the skin. We conclude that histiocytomas (dermal dendrocytomas) take their origin from dermal fixed connective tissue cells, (dermal dendrocytes), but other spindle cell tumours may differ in histogenesis.

SIR 2006 Film Panel Case: Spindle Cell Tumor of the Thigh

A 65-year-old Middle Eastern woman initially presented with left-sided pain in the pelvis and thigh and was evaluated for venous insufficiency. Computed tomography was performed, optimized to look for pelvic or ovarian varices. None were present. An enhancing contralateral thigh lesion (Fig 1) was found incidentally, only partially imaged. Ultrasonography (US) might have revealed the true nature of the lesion, but because the patient had a distant history of right hip dislocation and pelvic trauma, angiography was performed in anticipation of treatment of a pseudoaneurysm. Instead, a well-circumscribed oval hypervascular mass 4 cm 3 cm was discovered. It received its blood supply from the internal iliac artery (Fig 2), with the predominant contribution from the inferior gluteal artery (Fig 3) and secondary supply from internal pudendal artery branches. Even though the patient was asymptomatic and the lesion had a benign angiographic appearance, the differential diagnosis was expanded to include a posttraumatic sarcoma or a tumor related to the sacral nerve. Surgical excision therefore seemed inevitable, and the arterial feeder vessels to the lesion were occluded (Fig 4) with 0.018-inch Tornado platinum embolization coils (Cook, Bloomington, IN) to minimize the risk of hemorrhage and facilitate identification at the time of surgery. A wide surgical resection was performed, and the postoperative course was uneventful. Histologic analysis revealed a very well circumscribed benign spindle-cell tumor with a prominent vascular pattern and large staghorn vessels. There was no discernible necrosis or mitotic activity, and there were variable amounts of adipose tissue. Immunoperoxidase staining was positive for collagen type 4, BCL-2, CD34, and CD99.