Epithelioid angiomatous nodule of head and neck

Epithelioid vascular proliferations comprise a wide morphologic spectrum, ranging from reactive hyperplasia via benign tumor to malignant conditions. Epithelioid angiomatous nodule (EAN) is a recently recognized benign vascular proliferation with distinct clinical and pathological features.We review the literature and present six additional EANs in the head and neck examined by immunohistochemistry.This series comprised an equal number of males (n=3) and females (n=3) aged 13–45 years (mean 25.8 years). The sites of origin included the tongue (n=2), skin of the lip (n=2), periorbital and temporal skin (n=1), and nose (n=1). A painless solitary nodule (n=4) was the most common presentation. The lesions were distributed in the epidermis and subcutis, with a characteristic unilobular solid proliferation of polygonal epithelioid endothelial cells with intracytoplasmic primitive lumina.The distinction of EAN from other lesions of the heterogeneous group with epithelioid vascular proliferation can usually be made on the basis of the clinical and morphological features. This series indicates that the distribution of EAN in the head and neck region is not uncommon, which is in contrast to what was initially thought. EAN may be a variant of epithelioid hemangioma.     

Dermal squamo-melanocytic tumor: a unique biphenotypic neoplasm of uncertain biological potential.

We report four cases of an unusual cutaneous squamo-melanocytic neoplasm with histological features of malignancy and uncertain biological potential. These tumors developed on the face of middle-aged and older adults. Clinically, a purple-black nodule ranged in size from 3 to 10 mm in maximum diameter. After complete excision, neither recurrence nor metastasis has been observed (mean follow-up time, 3.25 years). Histologically, a discrete dermal nodule surrounded by a fibroblastic stroma was composed of large islands of mitotically active atypical epithelioid cells. The nodule was not connected to the epidermis in three of four cases. Two types of cells were either diffusely admixed or clustered in small groups within the nodule. Small, atypical, epithelioid cells containing finely granular brown pigment, proven to be melanin, constituted the first cell type. The second type consisted of atypical squamoid cells, some with abundant pink cytoplasm, giving rise to squamous pearls. A lentigo maligna was present in one case. The remaining three cases had neither significant intraepidermal melanocytic nor keratinocytic atypia. Immunohistochemical studies indicated that the melanin-containing epithelioid cells expressed S-100 antigens, and the squamoid cells expressed cytokeratins. A small population of tumor cells did not label with either of the antibodies. These four tumors (along with a previously reported, apparently identical tumor arising in the setting of lentigo maligna) represent a unique biphasic dermal neoplasm with histological features of malignancy but, at this time, uncertain biological behavior. Although none have recurred or metastasized, the follow-up time is too short in our estimation to guarantee a benign course. These neoplasms are easily recognized by their characteristic features. Further follow-up evaluations should allow determination of their biologic potential.     

Paragastric paraganglioma: a case report with unusual alveolar pattern and myxoid component

Paragangliomas are neural crest-derived neuroendocrine tumors. Nearly 5 to 10% occur in extraadrenal sites, from the upper cervical region to the pelvis, related to the autonomic nervous system. Very few cases of gastric or paragastric paragangliomas have been reported. We report a paraganglioma attached to the stomach of an 85-year-old man. The tumor was 15 cm in diameter and was surgically resected via a subtotal gastrectomy. Fine-needle aspiration smears showed round epithelioid cells forming acini and spindle cells attached to capillaries. Occasional cells showed excentric nuclei and pale vesicular cytoplasm. Microscopically, the tumor was characterized by an alveolar and solid pattern of growth with some unusual features, such as myxoid stroma and pseudoalveoli that contained myxoid material. Spindle cells stained with vimentin and S-100 protein, whereas epithelioid cells showed diffuse cytoplasmic staining with chromogranin A. Electron microscopy of the tumor tissue revealed the presence of neurosecretory granules. To the best of our knowledge, this pattern of growth has yet to be described in the literature and may result in a misdiagnosis if sufficient immunohistochemical markers are not employed. We briefly discuss the cytomorphological features and differential diagnosis of this tumor, which was discovered in a rare location.     

Fine-needle aspiration of hepatocellular carcinoma: False-negative result due to epithelioid cells

The presence of epithelioid cells in fine-needle aspirations of a liver nodule is rare, but may complicate the diagnosis of the nodule. We report on a case of a liver nodule in hepatitis C cirrhosis. Results of fine-needle aspiration mainly revealed the presence of epithelioid cells, without any recognizable tumor cells. Histological examination of the nodule after surgical resection showed a hepatocellular carcinoma with numerous epithelioid and gigantocellular granulomas, without necrosis.     

Uterine epithelioid endometrial stromal sarcoma presenting as a "cervical polyp"

Although appearance of conventional uterine endometrial stromal sarcoma is easily recognized on histology, it may uncommonly assume unusual appearances such as uterine tumor resembling ovarian sex-cord tumor, thereby hindering its diagnosis. Recently, its manifestation as an epithelioid neoplasm was described. In this report, we detail yet another instance where this tumor adopted an epithelioid morphology, presenting itself as a polyp extruding from the cervical os in a 41-year-old Chinese woman. Both the polypectomy and subsequent hysterectomy specimens revealed a predominant proliferation of CD10-negative, caldesmon-negative, and CD117-positive epithelioid cells set within a stroma containing vascular proliferation resembling endometrial stromal tumor. Areas of typical low-grade endometrial stromal sarcoma containing spindle cells that were focally positive for CD10 and negative for CD117 were present in close association with the epithelioid areas. The differential diagnoses and possible implication of CD117 positivity are discussed.     

Three cases of sclerosing lipogranuloma: an immunohistochemical study

Sclerosing lipogranuloma (SLG) is a rare disease that occurs in the male genital region. We report here three cases of SLG, including two of Y-shaped lesions in the penile base forming an intrascrotal mass, as well as a patient with a mass in the epidydimal region. All three lesions histologically exhibited formation of multiple granulomas consisting of multinucleated giant cells and epithelioid cells, in the fibroadipose tissue or around the epidydimis, in association with eosinophil infiltration. Membranocystic changes were found within the cytoplasm of multinucleated cells. In the two patients with scrotal lesions, membranocystic changes were positive for diastase-PAS reaction and on Sudan black B staining in dewaxed sections. CD68 staining was strongly positive in multinucleated giant cells and epithelioid cells. Most of the lymphocytes infiltrating the lesions were T cells associated with some S-100-positive dendritic cells. T-cell mediated immune reaction appears to be important in the histogenesis of SLG. The histogenesis is generally considered to be a foreign-body reaction to degenerated or damaged fatty tissue or lipids, but no apparent causative factors can be identified in some reported cases. All three patients in the present study had a good clinical course after biopsy or surgical excision. We thus report three cases of SLG including an unusual case in the epidydimal region, with some considerations regarding the histogenesis of SLG.     

Folliculocentric B-cell-rich follicular dendritic cells sarcoma: a hitherto unreported morphological variant mimicking lymphoproliferative disorders

We report three cases of follicular dendritic cell sarcoma (FDCS) showing a hitherto undescribed histological pattern consisting of nodular tumor growth associated with small B lymphocytes. FDCS tumor cells consistently showed large epithelioid features and were intermingled with small lymphocytes in the nodules in two cases, whereas they formed cohesive aggregates surrounded by lymphocyte mantle in the other. These features were easily confused with lymphomatous proliferations and, in particular, subtypes of Hodgkin lymphoma, high-grade follicular lymphoma, and germinotropic large B-cell lymphomas. The diagnosis was established by the use of a broad panel of antibodies that showed a variable expression of the FDC markers CD21, CD23, CD35, clusterin, podoplanin, claudin 4, epidermal growth factor receptor, and CXCL13. The associated B lymphocytes revealed a mantle zone B phenotype, with expression of CD20 and PAX5, together with TCL1 and IgD. Of notice, in all cases, morphological features suggesting hyaline-vascular Castleman disease were recognized in the interfollicular areas, containing scattered epithelioid cells similar to those found in the nodules, thus providing a useful clue for FDCS diagnosis. Of the 3 cases, 1 presented multiple recurrences unresponsive to chemotherapy and radiotherapy and finally died of disease 14 years after diagnosis. This study further emphasizes the extreme variability of morphological presentation of FDCS and expands the spectrum of lesions showing a nodular growth pattern occurring in human lymph nodes.     

Pulmonary epithelioid hemangioendothelioma: a tumor presented as a single cavitary mass

Pulmonary epithelioid hemangioendothelioma (PEH) is a rare tumor that occurs among young women and typically presents as bilateral multiple nodules. In the present report, we describe an uncommon case of PEH presented as a single cavitary nodule in a 33-yr-old asymptomatic man. This is the first case of PEH presented as a single cavitary nodule in the English literature. Three years of the follow-up without treatment was performed. Overall histologic findings were accord with conventional PEH, but some atypical features such as, increased mitotic activity (mean; two per ten high power fields), necrosis, spindling, and pleural and vascular invasion were recognized. Immunohistochemically, the tumor cells were positive for CD34. This report may contribute to the data on clinical findings and natural history of this rare tumor.     

Epithelioid fibrosarcoma of the ovary

Recently, low-grade fibromyxoid sarcoma/hyalinizing spindle cell tumor with giant rosettes (LGMFS/HSCT) and sclerosing epithelioid fibrosarcoma (SEFS) have come to be recognized as distinctive types of fibrosarcoma. Because their pathological features seem to sometimes overlap, it may be that these tumors belong to a similar entity. We report an aggressive sarcoma with unusual histology arising from the right ovary of a 44-year-old woman. The tumor was 12 cm in size, and there were multiple distant metastases to lung, kidney, stomach and bones. Microscopically, the tumor was composed of broad sheets or variously sized nodules of polygonal epithelioid cells accompanied by hyalinous stroma, resembling SEFS. The hyalinous nodules surrounded by the palisading epithelioid cells, as seen in a rosette of HSCT, were scattered. Between these nodules, spindle cells arranged in fascicles or whorled bundles, mimicking LGMFS, proliferated. Immunohistochemical and ultrastructural analyses revealed fibroblastic differentiation of epithelioid cells and the myofibroblastic nature of the spindle tumor cells. We think the present tumor is a distinctive epithelioid fibrosarcoma with the combined features of SEFS and LGFMS/HSCT, suggesting their intimate relationship.     

Cellular neurothekeoma, a rare cutaneous tumor. Anatomo-clinical and immunohistochemical study of 2 cases

Cellular neurothekeoma is an unusual cutaneous tumor described in 1986. We report two new cases in 14-year-old girls. Both tumors measured less than one centimeter and were located on the forearm and the shoulder. They had a plexiform architecture and were developed in the dermis and the dermo-hypodermic junction. Spindle and epithelioid tumor cells were immunoreactive for vimentin, NKI-C3, NSE, CD68 and smooth muscle actin. There was no recurrence 2 and 7 months after the operation. Cellular neurothekeoma is a benign tumor. Its histogenesis is still unknown. Histological and immunohistochemical features, with positivity of the tumor cells for NKI-C3, a non specific melanocytic marker, and negativity for S-100 protein and HMB-45, allow to differentiate cellular neurothekeoma from myxoid neurothekeoma and melanocytic tumors.     

Pulmonary epithelioid hemangioendothelioma with prominent signet ring cell features mimicking metastatic adenocarcinoma

We report the case of a 65-year-old woman who presented with persistent dry cough and was initially treated for pneumonia without much improvement. Computed tomography of the chest showed a 2.5 cm poorly marginated right infrahilar opacity and multiple ill-defined ground glass opacities scattered throughout the lungs. Computed tomography-guided fine needle aspiration of the right infrahilarmass showed malignant epithelioid cells, many of which were strikingly plasmacytoid with a vacuolated cytoplasm suggesting signet ring cells. A diagnosis of adenocarcinoma with signet ring cell features was made and, in view of the clinical history of multiple masses in the lung, metastatic adenocarcinoma from sites such as gastrointestinal or pancreaticobiliary tract was favored. The patient underwent exploratory thoracotomy during which she was found to have multiple, small pulmonary nodules, one of which was sampled for intraoperative examination. Frozen section of the nodule was interpreted as adenocarcinoma with signet ring cell features, probably metastatic in origin. Histopathologic examination of the pulmonary nodules demonstrated fairly well-delineated lesions with an acellular central zone of hyalinized matrix surrounded by a more cellular zone of moderately pleomorphic epithelioid cells, some of which had a peripherally displaced nucleus and vacuolated cytoplasm resembling signet ring cells. The epithelioid cells were positive for vascular markers CD31 and CD34 and, therefore, a diagnosis of epithelioid hemangioendothelioma was confirmed. This case clearly indicates the importance of recognizing the cytomorphologic and histologic spectrum of this entity to avoid misdiagnosing it as either primary or metastatic adenocarcinoma.     

Nontuberculous mycobacteria‐associated spindle cell pseudotumor of the nasal cavity: A case report

Mycobacterial spindle cell pseudotumor (MSP) is a rare mass‐forming lesion caused by mycobacterial infection, mostly in immunocompromised patients. Since it is composed of a proliferation of spindle‐shaped fibrohistiocytic cells without forming epithelioid cell granulomas, histological distinction from other spindle cell lesions is often difficult and its pathophysiology is poorly understood. MSP arising in the nasal cavity is extremely rare, and only two cases have been reported previously. Here we report a case of MSP of the nasal cavity in an 83‐year‐old man with no evidence of immunodeficient state. The resected tumor consisted of spindle cells, which contained numerous acid‐fast bacilli in the cytoplasm. By polymerase chain reaction and sequencing using DNA extracted from the paraffin sections, the bacilli were identified as Mycobacterium intracellulare. Immunohistochemistry revealed that the spindle cells were positive for CD68, CD11c and S100 protein, confirming the histiocytic nature of these cells. They were also positive for CD163 and CD204, suggesting that they showed a phenotype similar to alternatively activated (M2) macrophages and the phenotype might contribute to the maintenance of mycobacterial infection despite apparent immunocompetence of the host.     

Epithelioid Hemangioendothelioma of the Spermatic Cord

This report describes an epithelioid hemangioendothelioma arising on the spermatic cord of a 50-year-old man who presented with a nodule in the right hemiscrotum. Histologic examination showed a cellular tumor composed of epithelioid cells, many of which had intracytoplasmic lumina containing red blood cells. Immunohistochemistry showed focal positivity of tumor cells with the endothelial markers CD34, factor VIII-related antigen, and Ulex and with the anticytokeratin antibodies CAM5.2 and AE1/AE3. Ultrastructural examination revealed polygonal tumor cells forming vascular spaces and intracytoplasmic lumina containing red blood cells. This is the second documented occurrence of epithelioid hemangioendothelioma at this site. The case illustrates the value of immunohistochemistry and electron microscopy in establishing a diagnosis. Int J Surg Pathol 8(1):75-78, 2000     

Epithelioid sarcoma of the penis: report of an unusual case and review of the literature

Epithelioid sarcoma is a rare, slowly growing soft tissue tumor that uncommonly involves the penis, with only 11 previously reported cases. We present a case of penile epithelioid sarcoma in a 39-year-old man that mimicked Peyronie's disease, which was diagnosed 13 years following initial presentation. Preoperative magnetic resonance imaging showed multiple peripherally enhancing low signal intensity nodules involving the corpora cavernosa bilaterally. Following penectomy, histologic examination showed the typical features of epithelioid sarcoma, with a prominent pseudogranulomatous pattern. Immunohistochemically, the neoplastic cells demonstrated strong and diffuse staining for cytokeratins (AE1/AE3 and CAM 5.2), vimentin, epithelial membrane antigen, and CD34. Stains for S-100 protein, desmin, smooth muscle actin, and CD31 were negative. Electron microscopy demonstrated abundant intracytoplasmic intermediate filaments, scattered tonofilaments, and interdigitating filopodia. The present study is the first to describe magnetic resonance imaging and comprehensive immunohistochemical findings in penile epithelioid sarcoma. The majority of cases reported in the literature have demonstrated features similar to those typically found in epithelioid sarcoma involving the distal extremities. Consideration of epithelioid sarcoma in the differential diagnosis of a penile nodule or obstructive urinary symptoms may lead to early diagnosis and treatment.     

Pulmonary gangliocytic paraganglioma: a case report and review of the literature

Gangliocytic paraganglioma (GP) is a rare histologic type of neuroendocrine tumors. We report a case of pulmonary GP in a 29-year-old male presenting with an asymptomatic endobronchial nodule. Grossly, the tumor showed a 4.0x3.8x3.5 cm well-defined nodule with yellowish cut surface. Microscopically, the tumor was composed of three distinct cellular types: epithelioid cells, ganglion-like cells and spindle cells. Meanwhile, transitional cells, having morphologic features between ganglion-like and epithelioid cells, were also presented. The epithelioid cells arranged in various morphologic architectures, including Zellballen, papillary, cystic and microcystic pattern. The epithelioid cells were positive for AE1/AE3, CAM 5.2, chromogranin A and synaptophysin. Ganglion-like cells showed immunoreactivity for chromogranin A and synaptophysin. A few ganglion-like cells were also positive for AE1/AE3 and/or CAM 5.2. The spindle cells were positive for S-100 protein and neurofilament. The transitional cells showed a similar immunohistochemical profile to the epithelioid cells. The authors believe stem cell theory is a reasonable explanation for the origin of GP. GP probably originate from some kind of mucosa associated stem cell which can differentiate into diverse cellular lineages.     

Triple synchronous neoplasms in one kidney: report of a case and review of the literature

We report the case of a patient with three synchronous but histologically different primary renal tumors that were all in the same kidney. Two tumors were different subtypes of renal cell carcinoma (RCC), and the third was a variant form of angiomyolipoma. The patient was a 62-year-old man who was receiving antihypertensive drugs and came to our hospital for a regular check-up. Ultrasonography performed during the visit revealed a left renal mass, but the patient had no related symptoms. Subsequent computed tomography revealed two round, high-density masses, one in the mid-portion and the other in the lower pole of the left kidney, and multiple cysts in the right kidney and the liver. The mass in the mid-portion measured 3.3 x 3.0 x 2.8 cm, and the mass in the lower pole measured 1.7 x 1.1 x 0.9 cm. A left radical nephrectomy was performed. On gross examination, an additional ovoid nodule (0.6 cm in the greatest dimension) was found in the lower pole. Microscopically, the largest tumor consisted of a broad alveolar arrangement of large round cells with abundant eosinophilic or clear cytoplasm, distinct cell borders, and perinuclear halos, features consistent with chromophobe RCC. The smallest tumor was a conventional (clear-cell) RCC. The third tumor was composed solely of atypical epithelioid cells with prominent nucleoli and yellowish-brown to black pigments. The tumor cells were positive for melanin (Fontana-Masson stain), the melanoma marker HMB45, vimentin, smooth-muscle actin, and the macrophage marker CD68 and were negative for cytokeratin. This tumor was considered a pigmented epithelioid type of angiomyolipoma. The histologic, histochemical, and immunohistochemical features in this case confirmed the presence of three synchronous primary tumors, a chromophobe and a clear-cell type RCC and a pigmented epithelioid angiomyolipoma, all of which were in the same kidney. This case is the first of its type reported in the literature.     

Pancreatic perivascular epithelioid cell tumor (PEComa)

Neoplasms with perivascular épithelioid-cell differentiation (PEComas) are rare tumors with a distinctive immunoreactivity for melanocytic markers. They have been described in various organs. We report an intrapancreatic PEComa discovered in a 46-year-old woman during a workup for diarrhea. CT scan showed a 1.7cm nodule in the body of the pancreas with slight-contrast enhancement at arterial time and isodense at portal time. The aspect was suggestive of an endocrine tumor despite negative somatostatin-receptor scintigraphy. Enucleation was performed. Pathologic evaluation showed a well-circumscribed intrapancreatic tumor consisting of a population of clear to eosinophilic spindle cells and a less abundant population of epithelioid cells arranged around blood vessels. Tumor cells expressed vimentin, HMB45 and actin and only focally S-100 protein, KL1, CD117 and CD34. These features were consistent with a PEComa. Pancreatic PEComas are rare, but should be included in the differential diagnostic of pancreatic clear cells tumors or pancreatic spindle- and epithelioid-cells tumors.     

A typical postcesarean epithelioid trophoblastic lesion with placenta increta: Case report and literature review

We report an extremely rare case of unusual atypical epithelioid trophoblastic lesion from placenta increta. A 25-year-old Chinese woman with a history of 1 cesarean delivery was admitted to the hospital at 37 weeks’ gestation. Magnetic resonance imaging (MRI) showed the feature of placenta increta. An elective primary cesarean section was scheduled and a healthy baby was born. The patient was suggestive of placenta increta and implantation site was resected. Histology indicated a lesion consisting of epithelioid trophoblastic cells with an intermediate pattern between a classical placental site nodule and an epithelioid trophoblastic tumor. This may be linked to her previous cesarean delivery, which supports the relationship between atypical epithelioid trophoblastic lesion formation and surgical interventions. Her serum human chorionic gonadotropin (hCG) was 352.4 IU/L after delivery and gradually decreased to normal level.     

Nasal administration of recombinant rat IL-4 ameliorates ongoing experimental autoimmune neuritis and inhibits demyelination

Experimental autoimmune neuritis (EAN) is a CD4(+)T cell-mediated demyelinating disease of the peripheral nervous system (PNS) and serves as an experimental model for human immune-demyelinating neuropathies. In this study, we examined the effect of recombinant rat interleukin-4 (rrIL-4) on chronic EAN in Lewis rats induced by immunization with P0 peptide 180-199 and complete Freund's adjuvant (CFA). We estimated that nasal administration of rrIL-4, in dose ranges of 0.1-1 microg/rat/day in the initial phase of EAN, decreased the severity and the duration of clinical EAN. Hyporesponsiveness of T cells, downregulation of Th1 cell responses (INF-gamma), but increased levels of specific IgG1 isotypes document that nasal administration of rrIL-4 was systemically immune effective. Low grade inflammation and complete lack of regional demyelination within the sciatic nerves were seen in rrIL-4 treated rats. Based on these observations we suggest that nasal administration of IL-4 could be further evaluated, considering its possible use in human immune-demyelinating neuropathies.     

Epithelioid leiomyosarcoma with osteoclast-like giant cells in the rectum

We report a rare case of rectal epithelioid leiomyosarcoma with osteoclast-like giant cells. A 71-year-old Japanese man was admitted to a hospital with melena. Results of a colonoscopy test revealed a polypoid tumor in the rectum, and a biopsy specimen from the lesion showed a sarcoma; the patient underwent rectosigmoidectomy. At gross inspection, the tumor measured 8 x 7 x 4 cm and was polypoid with ulcerations. Necrotic and hemorrhagic foci were scattered. Microscopically, the tumor consisted of 2 cell types: malignant tumor cells with epithelioid features and benign-appearing osteoclast-like giant cells. The tumor cells were polygonal and epithelioid in shape and had eosinophilic or clear cytoplasms, with scattered giant tumor cells. Immunohistochemical examination revealed that the tumor cells were positive for vimentin, muscle actin, alpha-smooth muscle actin, and desmin, whereas the osteoclast-like giant cells were positive for CD68, leukocyte common antigen, and lysozymes. We diagnosed this case as epithelioid leiomyosarcoma with osteoclast-like giant cells. To the best of our knowledge, this is the first case of rectal epithelioid leiomyosarcoma with osteoclast-like giant cells.