Extranodal follicular dendritic cell sarcoma of the tonsil - case report of an epithelioid cell variant with osteoclastic giant cells

Follicular dendritic cell sarcomas are rare neoplasms arising from the accessory cells of the lymph nodes, the follicular dendritic cells. They commonly occur in the lymph nodes, but have also been reported at extranodal sites (especially the tonsil). At both sites, there is usually a proliferation of spindled to ovoid cells, mimicking a mesenchymal tumor. Herein, we report a tonsillar tumor in a 50-year-old man, which was composed exclusively of large polygonal cells and numerous osteoclastic giant cells that resembled a giant cell carcinoma. The true nature of the tumor was revealed after an array of immunohistochemical stains. The patient is well 4 years after tonsillectomy.     

Interdigitating dendritic cell sarcoma of lymph node mimicking granuloma: a case report and review of the literature

Interdigitating dendritic cell sarcoma (IDCS), is an extremely rare neoplasm. We report a case of a 77-year-old man presented with gradual lymph nodes enlargement in inguina, neck and axilla for 6 months. Biopsy revealed that part of the lymph node was replaced by several large granuloma-like nodules composed of mild atypical tumor cells, resembling epithelioid cells. Mitotic figures were hardly found. Immunohistochemistry showed that tumor cells were positive for S-100, CD68 and CD45. Ki-67 labeling index was 5%. To the best of our knowledge, this is the first case of IDCS showing granuloma-like growth pattern with mild atypical tumor cells.     

The diagnostic utility of Merkel cell polyomavirus immunohistochemistry in a fine needle aspirate of metastatic Merkel cell carcinoma of unknown primary to the pancreas

Merkel cell carcinoma (MCC) is an aggressive skin tumor with a high tendency for metastases. We report a case of MCC initially presenting as axillary and pancreatic metastases. A 33‐year‐old HIV‐positive Hispanic male presented with a history of a rapidly growing axillary mass. A needle core biopsy demonstrated an epithelioid neoplasm composed of small to medium‐sized cells with high nuclear‐cytoplasmic ratio, nuclear molding, and frequent mitotic figures. A subsequent PET scan revealed a 1.5 cm FDG avid mass in the pancreas. Endoscopic ultrasound‐guided FNA of the pancreatic mass showed neoplastic cells with similar morphology to those of the axillary mass. The tumor cells were positive with pancytokeratin AE1/AE3, CK20, CD56, synatophysin, chromogranin, and Merkel cell polyomavirus (MCPyV). This case of MCC most likely originated from a resolved primary skin lesion drained by the involved axillary lymph node with subsequent metastases to the pancreas and distant lymph nodes.     

Follicular dendritic cell tumor of the mediastinum: expression of fractalkine and SDF-1α as mast cell chemoattractants

Follicular dendritic cell tumor (FDCT) is a rare tumor mainly located in laterocervical lymph nodes. We report one case of mediastinal FDCT associated with a history of bullous skin disease and clinically obvious immunosuppression. This tumor was characterized by heavy mast cell infiltration. Mast cells were in close relationship with tumor cells as demonstrated by ultrastructural examination and their presence are probably related with the strong expression of mast cell chemoattractants as fraktalkine and stromal cell-derived factor-1α by tumor cells. The long follow-up period of more than 17 years allowed to us assess the relatively indolent evolution of this tumor characterized by three slowly growing local recurrences without metastasis.     

Extranodal follicular dendritic cell sarcoma of the soft palate: a case report

Follicular dentritic cell sarcoma (FDCS) is an extremely rare malignant neoplasm arising from the accessory cells of the lymph nodes, the follicular dendritic cells. They commonly occur in the lymph nodes, but have also been reported at extranodal sites. Because of its rarity, FDCS is not easily to make a diagnosis by clinicians or pathologists. Herein, we report a soft palate tumor in a 59-year-old female, with a history of tonsillectomy. Pharynx MRI scan revealed a 4.7×3.0×3.5 cm mass at the right side of the parapharyngeal space. The pathology results returned as Follicular dentritic cell sarcoma. The patient underwent a tumorectomy and adjuvant postoperative radiotherapy. The patient was free of disease 1 year after the end of the treatment. The FDCS is an infrequent nonlymphoid malignant tumor accounting for less than 1% of all head and neck tumors. The immunohistochemical technique is essential for accurately identifying this class of tumour.     

Follicular dendritic cell sarcoma with microtubuloreticular structure and virus-like particle production in vitro

Neoplasm of follicular dendritic cells (FDC), follicular dendritic cell sarcoma (FDCS), is a rare tumor of intermediate to high-grade malignancy in lymph nodes and visceral organs. Reported herein is a case of FDCS arising from cervical lymph nodes in a 16-year-old Japanese boy, who died of the disease 3 years after diagnosis. The tumor cells were pale eosinophilic and elongated with euchromatic nuclei and were positive for CD21, clusterin, and CNA-42 on immunohistochemistry, as well as desmosome-like junctions on electron microscopy. The presence of microtubuloreticular structures (MTRS) in the tumor cells and associated lymphocytes characterized this case, suggesting some viral infection, although qualitative polymerase chain reaction of genomic and complementary DNA obtained from the tumor failed to demonstrate any viral infection at the laboratory level. The stimulation of dispersed tumor cells and peripheral blood mononuclear cells with mAb to CD3 and interleukin-2 was attempted; and the cell line established by the authors (FDCS-Sa) was stimulated with iododeoxyuridine. Virus-like particles (VLP) were successfully induced from each cellular source. The VLP, 100 nm in diameter, showed an electron-dense thorny envelope and granular core. This is the first case of FDCS with MTRS accompanying VLP production in vitro .     

Langerhans cell sarcoma involving gallbladder and peritoneal lymph nodes: a case report

Langerhans cell sarcoma (LCS) is a rare proliferation of Langerhans cells with overtly malignant cytologic features and spreads aggressively. LCSs show a multiorgan involvement, including skin, lymph nodes, lung, and bone. The authors report an LCS in a 74-year-old woman that involved the gallbladder and the peritoneal lymph nodes. Imaging revealed a tumor in the gallbladder and the peritoneal lymph nodes. The tumor cells were positive for CD1a, S-100 protein, and Langerin (CD207). Although the ultrastructural analysis failed to demonstrate any Birbeck granules, the histomorphological and immunohistochemical findings supported the diagnosis of LCS. After surgical resection, she showed no recurrent or metastatic signs for 8 months without any other adjuvant therapy. This is the first case of LCS involving the gallbladder and the peritoneal lymph nodes. This report also includes a review of the literature concerning this rare disease.     

Mediastinal follicular dendritic cell sarcoma involving bone marrow: a case report and review of the literature

We report a rare case of mediastinal follicular dendritic cell (FDC) sarcoma involving the bone marrow. The patient, a 46-year-old woman, had a clinically aggressive tumor in the anterior mediastinum that was initially diagnosed as a diffuse B-cell lymphoma. She received chemotherapy but showed no significant improvement. One year later, the patient presented at our institution with pelvic bone metastases. Biopsy specimens of the sacrum lesion and bone marrow were obtained. The diagnosis of FDC sarcoma was made based on histological examination and immunohistochemical findings, including strong positive staining of tumor cells for CD21, CD23, clusterin, and epidermal growth factor receptor (EGFR) and negative staining for CD20, CD30, CD45, CD1a, S-100, vimentin, and keratin cocktail. Histological examination and immunohistochemical studies of a previous biopsy of the mediastinal mass confirmed the diagnosis of mediastinal FDC sarcoma. The patient was treated with an appropriate chemotherapy regimen; 1 month later, follow-up bone marrow biopsy revealed no tumor cells. Although FDC sarcoma is considered a low-grade tumor, the tumor in the present case not only developed at an unusual location with bone metastasis but also involved bone marrow. To our knowledge, this is the first such case ever reported. This case also highlights the utility of EGFR as an immunohistochemical marker of dendritic cell tumors that could be used as a diagnostic tool and guide for choosing appropriate chemotherapy regimens.     

Cytokeratin-positive interstitial cell neoplasm: a case report and classification issues

AIMS: Tumours of dendritic/accessory cell origin are rare neoplasms arising in lymph nodes. Among these, tumours derived from cytokeratin-positive interstitial reticulum cells (CIRCs), a subset of fibroblastic reticulum cells, are reported even less frequently. The International Lymphoma Study Group (ILSG) has recently proposed a classification for tumours of histiocytes and accessory dendritic cells in which CIRC tumours are not included. We report a case of a CIRC tumour arising in a submandibular lymph node of a 66-year-old male. METHODS AND RESULTS: The neoplasm was composed of spindle cells with elongated or round nuclei, prominent nucleoli and abundant cytoplasm. These cells were arranged in a diffuse fascicular and vaguely whorled pattern. The tumour cells stained diffusely for S100, vimentin, desmin, lysozyme, and focally for CD68 and cytokeratins 7, 8, 18, CK-AE1 and CK-pool. Electron microscopy was performed for further evaluation on samples taken from the paraffin block; this revealed cytoplasmic projections and rudimentary cell junctions. CONCLUSIONS: Histopathologist should be aware of the existence of tumours deriving from CIRCs, as these cases may be misdiagnosed as metastatic carcinoma. Careful clinical and pathological evaluation is necessary to exclude this possibility.     

Paraneoplastic pemphigus associated with follicular dendritic cell sarcoma: report of a case and review of literature

Follicular dendritic cell sarcoma (FDCS) is a rare tumor associated with paraneoplastic pemphigus. It is Blame drenchs auxiliary cell tumor which is derived from the peripheral lymphoid tissues. Throughout the world, several patients of paraneoplastic pemphigus associated follicular dendritic cell sarcoma were reported in the literature, but mostly originated from the neck lymph nodes, and extranodal origin of follicular dendritic sarcoma was rarely reported. Also, so far we have found that the malignant degree of all patients diagnosed with malignant tumors have been reported were low and after combined treatment of surgery, radiotherapy and chemotherapy, most of the prognosis was good. However, here we present a patient of paraneoplastic pemphigus associated with follicular dendritic cell sarcoma origined from outside of the lymph nodes and had high tumor malignant degree for its unclear cell boundaries, obvious atypia and mitoses and the patient’s state became progressively deteriorate after operation.     

Lymphoepithelial cystic lesion related to adenocarcinoma in the mediastinum

The authors report here a case of lymphoepithelial cystic lesion (LECL) of unknown origin in the mediastinum, which is closely related to a signet-ring cell adenocarcinoma. A 73-year-old man presented with a mass as revealed on a chest x-ray. During surgical operation, a solid, well-circumscribed and encapsulated 9 X 9 X 8 cm tumor was isolated from the right anterior mediastinum. This tumor had neither undergone metastasis nor invaded into the surrounding tissue and lymph nodes. Light microscopy revealed the tumor to be a signet-ring cell adenocarcinoma. Clinically, the neoplasm was coupled with an elevation in serum CEA level, which promptly returned to normal values following surgical removal. Immunohistochemistry pointed out that the majority of neoplastic cells stained positive for CEA. In addition, LECL of unknown origin was distinguished at the periphery of the tumor. LECL was characterized by microcysts which were lined by columnar epithelial and surrounded by lymphoid tissue with germinal centers. Transition between the neoplastic cells and benign epithelial cells of LECL was evident, showing that the previously mentioned mediastinal adenocarcinoma may be derived from the epithelial elements of LECL. This paper discusses the histogenesis of LECL.     

Reticulum cell sarcoma of lymph node with mixed dendritic and fibroblastic features.

We report a case of clinically aggressive reticulum cell sarcoma with mixed follicular dendritic cell (FDC) and fibroblastic reticular cell (FRC) features. Histologically, the tumor was confined to lymph nodes occurring as a multifocal epithelioid and spindle cell proliferation with appreciable mitotic rate and numerous admixed non-neoplastic B-cells. Ultrastructural examination revealed elongated cells with prominent nucleoli, interdigitating cell processes and frequent desmosomes. These features are typical of FDC sarcoma. However, immunohistochemical stains showed no expression of antigens characteristic of FDCs, including CD21, CD23 and CD35. Cytogenetic characterization of this tumor, by conventional G-banding and multicolor spectral karyotyping, revealed multiple clonal chromosomal aberrations, including del(X)(p11.4) and add (21)(p11.2). Gene expression analysis by cDNA microarray of RNA obtained from short-term tumor cultures revealed high-level expression of a set of genes (including PDGF receptor-alpha and -beta, certain metalloproteinases, and CD105) that were also highly expressed in cultures of nodal FRC cultured from non-neoplastic lymph nodes. We propose that this tumor represents a nodal sarcoma with intermediate differentiation between FDCs and FRCs. This case adds to the diversity of tumors that may arise from lymph node stroma and supports a possible relationship between the FDC and FRC lineages.     

Classic follicular dendritic reticulum cell tumor of the lymph node developing in a patient with a previous inflammatory pseudotumor-like proliferation

Inflammatory pseudotumor (IPT) and follicular dendritic reticulum cell tumor (FDRCT) are rare entities of the lymph node characterized by spindle-cell proliferation. We report a case of a 31-year-old woman, who was admitted for biopsy of a lymph node in the left submandibular area. The microscopic examination revealed a proliferation of spindle cells, partially replacing the normal lymph node architecture, suggestive of an IPT. The preserved peripheral portion showed follicular hyperplasia with Castleman-like appearance. Six years later she presented with a new enlargement in the same submandibular area. The nodule was removed, and a diagnosis of a classic FDRCT of the lymph node was made. The present case is remarkable, and clinicopathological data show that IPT-like proliferations could be in some case an early presentation of FDRCT.     

Papillary thyroid carcinoma-like tumor of the kidney: a case report

Thyroid carcinoma-like tumor of the kidney is an extremely rare variant of renal cell carcinoma. Most previously reported cases were incidental finding; and none of them showed papillary thyroid carcinoma (PTC) nuclear features. This study reports the first case of PTC (follicular variant)-like tumor of the kidney in which a female patient presented with hematuria, weight loss, and flank pain. Imaging studies revealed a left renal mass with enlarged hilar lymph nodes. Histologically, the renal tumor had a striking resemblance to follicular variant of PTC. However, no radiological abnormalities were found in the thyroid, mediastinum, or pelvis. Tumor cells were negative for thyroid markers (thyroglobulin and TTF1). According to the authors, this is the first case of PTC (follicular variant)-like tumor of the kidney.     

Histiocytic sarcoma - a case with evenly distributed multinucleated giant cells

Histiocytic sarcoma is an uncommon neoplasm of mature histiocytes with a poor clinical outcome. We report a case of a true histiocytic sarcoma with prominent and evenly distributed multinucleated giant cells that mimics a giant cell tumor of soft tissue. The tumor was located between the appendix, right ovary, and the terminal ileum with severe adhesion. The liver and spleen were not enlarged. Grossly, the tumor appeared grayish white, solid, and soft. Microscopically, polygonal mononuclear tumor cells aggregated to form somewhat epithelioid nests, which occasionally showed coagulative necrosis. Prominent and evenly scattered giant cells were present in all sections. In addition, tumor cell infiltration was noted in regional lymph nodes. The tumor cells were positive for lysozyme, CD68, CD163, and negative for T- and B-cell lineage markers, follicular dendritic cell, megakaryocytic, epithelial, muscular, and melanocytic markers, CD1a and CD30. This case posed great difficulty in clinical and pathological diagnoses. Gross pictures, microscopic findings, and extensive immunostains are important for the differential diagnosis.     

Follicular dendritic cell tumor of mesentery--a case report

Follicular dendritic cell sarcoma also known as dendritic reticulum cell tumor is uncommon. It can arise in lymph nodes and extra nodal sites namely tonsils and intra abdominal locations. The tumor morphologically mimicks soft tissue sarcomas and hence requires immunohistochemical study for correct diagnosis. It pursues an indolent protracted course with recurrence and still be compatible with long survival. We report a case of follicular dendritic cell tumor of mesentery.     

Malignant germ cell tumor of the anterior mediastinum with leukemia-like infiltration

We present here a rare autopsy case of malignant germ cell tumor with leukemia-like infiltration of the anterior mediastinum in a 35-year-old male. Chest X-rays revealed an abnormal mediastinum, which was diagnosed as thymoma. During the course of treatment, huge abnormal cells 40-50 mu in size were found in the peripheral blood smear and disseminated bone metastasis of the malignant thymoma was suspected. The tumor was resistant to both chemotherapy and radiotherapy. The patient died of respiratory failure. The autopsy disclosed a huge tumor measuring 24 X 13 X 10 cm in the anterior mediastinum. Histological findings of the tumor revealed cells which had spread to almost all organs, indicating leukemia-like infiltration. This pattern of metastasis has been reported in the cancer of non-hematologic origin under the term "carcinocythemia (CCA)". To our knowledge, the present case is the first report of a leukemia-like infiltration in case of malignant germ cell tumor. Careful serial section revealed no primary foci in either testis.     

Intra-abdominal follicular dendritic cell sarcoma with marked pleomorphic features and aberrant expression of neuroendocrine markers: report of a case with immunohistochemical analysis.

Follicular dendritic cell sarcoma (FDCS) is a very rare malignant tumor arising most frequently in lymph nodes with only few reports of extranodal locations. We report the case of a 35-year-old man with a large retroperitoneal mass. Histologically the tumor was composed of highly pleomorphic cells exhibiting some uncommon features such as an epithelioid appearance, cystic spaces, and multinucleated cells with morphologic features of emperipolesis. Immunohistochemically the neoplastic cells were immunoreactive for CD21, CD23 and CD35. A previously unreported expression of neuroendocrine markers (Synaptophisyn and Neuron-Specific-Enolase) was present. Ultrastructurally no neuroendocrine secretory granules were detected. FDCS can mimic a wide variety of other malignant tumors, and a correct diagnosis requires exclusion of other neoplasms and immunohistochemical confirmation.     

Mesothelial cell inclusions in pelvic and para-aortic lymph nodes: a clinicopathologic analysis

Benign lymph node inclusions are commonly encountered during surgery for gynecologic neoplasms and are potential mimics of metastatic tumor. The presence of mesothelial cell inclusions in pelvic lymph nodes is extremely rare. We report the clinicopathologic features of 10 patients with ovarian tumors and mesothelial cell inclusions detected in the sinuses of pelvic and paraaortic lymph nodes. All patients had concurrent massive ascites and mesothelial cell hyperplasia at the time of lymph node dissection. Histologically, nodal mesothelial cells were identified predominantly within the subcapsular, trabecular and medullary sinuses. Moreover, intra- and extranodal lymphatics also contained mesothelial cells, confirming their mode of lymphatic transport to nodal sinuses. This finding, together with mesothelial cell hyperplasia and massive ascites suggest that mesothelial cells derive from reactive serosal mesothelium and are dislodged into draining lymphatics. This study indicated the pathogenic significance of the lymphatic transport mechanism. Nodal mesothelial cell inclusions should be distinguished from metastatic tumor to avoid inaccurate staging in a patient with a known tumor or the false negative diagnosis of an occult primary tumor. Recognition of this entity by immunohistochemical evaluation in addition to routinely stained sections is important to prevent a diagnosis of metastatic carcinoma or malignant mesothelioma.     

Sarcoma of follicular dendritic cells with features of sinus lining cells—a new subtype of reticulum cell sarcoma?

Dendritic cell neoplasms of the World Health Organization classification comprise Langerhans cell histiocytosis, Langerhans cell sarcoma, interdigitating dendritic cell sarcoma, follicular dendritic cell sarcoma, and dendritic cell sarcoma, not otherwise specified. Several studies based on immunohistochemical and ultrastructural analysis tried to further clarify the origin of these neoplasms which are thought to derive from mesenchymal or bone marrow precursors. Lymphatic vessel endothelium hyaluronan receptor-1 (LYVE-1) was recently described as a marker for lymphatic endothelium which is expressed on normal liver blood sinusoid lining cells, spleen endothelium, activated tissue macrophages, blood vessels in the lung, endothelial cells of lymphatic sinuses, and in fibroblastic reticular cells in lymph nodes. We present a case of LYVE-1-positive reticulum cell neoplasm in an axillary lymph node. To the best of our knowledge, there has been no report about LYVE-1 expression in histiocytic or dendritic cell neoplasms so far. Due to the assumed specificity of this antibody, we propose designation of this reticulum cell sarcoma as lymphatic sinus lining cell sarcoma which might finally represent another subtype of reticulum cell sarcomas.