Urothelial carcinoma of the renal pelvis with rhabdoid features

Reported herein is the case of a 70-year-old man with high grade urothelial carcinoma (UC) with rhabdoid features of the renal pelvis. For the most part, the tumor was composed of pleomorphic, non-cohesive round tumor cells with abundant cytoplasm. In situ high-grade UC composed of cohesive tumor cells was seen only in a small portion. Pleomorphic dyscohesive tumor cells often showed rhabdoid features, containing eosinophilic inclusions. These pleomorphic/rhabdoid tumor cells were immunohistochemically positive for vimentin but negative for cytokeratins, CD45, CD20, CD79a, CD3, CD45RO, CD38, and CD138. Loss of heterozygosity (LOH) analysis demonstrated identical allelic losses as well as additional allelic losses for the dyscohesive and cohesive UC lesion, indicating that these two lesions originated from a single clonal lesion.     

Granzyme B-positive primary gastric T-cell lymphoma: gastric T-cell lymphoma with the possibility of extrathymic T cell origin

A case of primary gastric T-cell lymphoma, which was positive for granzyme B, is reported. The patient was a 47-year-old Japanese female who complained of a dull upper abdominal pain. Radiographic and endoscopic examinations revealed an ulcerative infiltrative lesion in her stomach. Following the confirmation of a high-grade malignant lymphoma, a distal gastrectomy with regional lymph nodal dissection was performed. The histology of the gastric lesion revealed a malignant lymphoma of the diffuse pleomorphic type without lymph nodal involvement. Immunohistochemistry revealed that the tumor cells were positive for LCA, CD3, TIA-1 and granzyme B, but were negative for CD4, CD8, CD56, CD30, L-26, EMA, TCR alpha/beta and TCR gamma/delta. Because the tumor cells showed T cell nature with cytotoxic activity proved by TIA-1 and granzyme B, and without evidence of further maturation of T cell, a malignant lymphoma originating from extrathymic-derived T cells was suggested.     

Characterization of endoglin and Ki-67 expression in endothelial cells from benign and malignant lesions of the uterine cervix

Activation of endothelial cells is often associated with the cellular proliferation in vitro . CD105 is a more specific marker of activated endothelial cells from tumor vessels and Ki-67 is used to assess the proliferation status of both tumor and endothelial cells. The aim of the present study was to evaluate the status of endothelial cells using CD105 and Ki-67 immunohistochemistry in benign and malignant lesions of the uterine cervix. Double stain for CD105/Ki-67 in benign and malignant lesions of the uterine cervix showed that these two markers had divergent expression on endothelial cells from associated tumor blood vessels dependent on lesion type and proliferation status of tumor cells. Absence of CD105/Ki-67 coexpression in endothelial cells was correlated with histopathology of the uterine cervix lesions and tumor proliferative status. The present findings suggest that CD105 expression is an early event, specific for premalignant lesions of the uterine cervix, while endothelial proliferation assessed on Ki-67 combined with the lack of CD105 expression is often associated with invasive cervical carcinoma.     

白细胞相关免疫球蛋白样受体-1在宫颈癌和子宫内膜癌患者外周血T细胞的表达及意义

目的 研究白细胞相关免疫球蛋白样受体(LAIR-1)在宫颈癌和子宫内膜癌患者外周血T细胞的表达情况,并与子宫肌瘤、子宫癌前病变患者相比较,探讨LAIR-1表达与肿瘤免疫的相关性.方法 密度梯度离心法分离外周血单个核细胞,流式细胞术检测LAIR-1在196例肿瘤患者外周血T细胞的表达水平.结果 流式细胞术检测结果显示,宫颈癌和子宫内膜癌患者外周血CD3+CD4+T细胞LAIR-1阳性率均高于子宫肌瘤(P＜0.001;P＜0.05)和癌前病变患者(P ＜0.001;P ＜0.01).平均荧光强度分析结果显示,宫颈癌患者外周血CD3+CD4+T细胞LAIR-1表达水平显著高于癌前病变患者(P＜0.01),CD3+CD8+T细胞LAIR-1表达水平显著高于子宫肌瘤患者(P＜0.05)和癌前病变患者(P＜0.001).子宫内膜癌患者外周血CD3+CD4+T细胞LAIR-1表达水平明显高于子宫肌瘤患者(P＜0.05)和癌前病变患者(P＜0.01),CD3+CD8+T细胞LAIR-1表达水平高于癌前病变患者(P＜0.05).结论 LAIR-1在宫颈癌和子宫内膜癌患者外周血T细胞表达上调,提示LAIR-1可能与肿瘤免疫逃逸存在相关性.     

Spontaneous regression of malignant lymphoma of the breast

A complete spontaneous regression of diffuse large B cell lymphoma involving the right breast, confirmed by aspiration cytology, is reported. The patient visited a hospital due to the rapid growth of a tumor in the right breast. Five years previously she underwent a craniotomy for a brain tumor, diagnosed as B-cell malignant lymphoma, and received several courses of irradiation to the brain. Analysis of the breast tumor cells obtained by aspiration revealed lymphoma cells morphologically, which were similar to the tumor cells in the brain expressing CD20. While waiting for further examination, the tumor regressed rapidly and was not palpable after 20 days. An excisional biopsy of the breast exhibited no definite malignant lymphoma cells among a diffuse population of CD45RO and CD8-positive small lymphocytes. Nucleotide sequencing of HCDR3s of the brain tumor and breast tumor cells showed a completely matched sequence, revealing the breast mass to be a metastatic lesion from the tumor of the brain. Although there was no tumorous lesion, the patient received additional chemotherapy and has shown no sign of recurrence in the breast for 7 years. We were able to confirm that the breast lymphoma shown in the aspiration cytology was a metastatic one, which was not proven histologically prior to chemotherapy, and regard the present case as a malignant lymphoma of the breast showing spontaneous regression. The present case shows a rare occurrence of spontaneous regression of diffuse large B cell malignant lymphoma after aspiration and suggests that CD8-positive T cells might be related to the regression.     

Low-grade periductal stromal sarcoma of the breast with myxoid features: Immunohistochemistry

A 52-year-old woman was admitted with a painful right breast tumor measuring more than 20 cm in largest diameter, which ulcerated the overlying skin. The lesion had appeared 4 years previously but the patient hesitated to seek medical care due to 'fear of cancer'. Microscopically, the tumor was composed of spindle cells that formed cuffs around multiple open tubules and ducts set in an abundant, myxoid stroma. The spindle cells had significant atypia with nuclear pleomorphism, occasional cytoplasmic vacuolation and moderate mitotic activity. The ducts and lobules surrounded by the proliferating tumor cells had minimal distortion, with a pericanalicular growth pattern devoid of the phyllodes pattern. The tumor had a multinodular growth pattern with coalesced and individual tumor nodules, the latter being found mostly at the periphery of the lesion. On immunohistochemistry the tumor cells were positive for smooth muscle actin, CD34, and vimentin, and focally positive for CD10. A diagnosis of low-grade periductal stromal sarcoma (PDSS) with myxoid features was established. PDSS is a distinct low-grade breast sarcoma, the appropriate diagnosis of which requires extensive tumor sampling and additional broad immunohistochemistry. PDSS should not be confused with other spindle cell breast tumors because they require different treatment.     

Malignant diffuse-type tenosynovial giant cell tumor of the buttock

Malignant diffuse-type tenosynovial giant cell tumor (D-TSGCT) is an unusual sarcoma. We report a case of malignant D-TSGCT located in the left buttock. A 58-year old woman noticed a small mass at her left buttock 3 months previously. The mass tended to enlarge rapidly, and became 6 cm in diameter. Tumor resection was performed. Grossly, the tumor showed a solid growth pattern and whitish appearance with hemorrhage and necrosis. Microscopically, the tumor was composed of a proliferation of short spindle and oval mononucleated cells with numerous osteoclast-like multinucleated giant cells, which occasionally showed coagulative necrosis. In addition, tumor cells had high mitotic activity and atypical mitoses. Immunohistochemically, the mononucleated cells were positive for CD163 and focally positive for CD68 (clone KP-1 and PG-M1), CD4, smooth muscle actin and S100 protein. Osteoclast-like multinucleated giant cells were positive for CD68 (clone KP-1 and PG-M1) and CD4. Pulmonary metastases were found 6 months after the operation. These findings indicate that this lesion is consistent with malignant D-TSGCT.     

Neuroendocrine carcinoma of the posterior mediastinum: a possible primary lesion.

A paravertebral mass was noted in the posterior mediastinum in a 47-year-old man. Microscopically, the tumor showed solid and trabecular patterns and consisted of poorly differentiated atypical cells that often formed Flexner-Wintersteiner rosettelike glands. Immunohistochemically, the tumor cells expressed both epithelial and neuroendocrine markers, including cytokeratin (AE1/3), carcinoembryonic antigen, epithelial membrane antigen, neuron-specific enolase, chromogranin A, and synaptophysin, but were negative for CD99 (MIC2). Ultrastructurally, numerous desmosomes and neurosecretory granules were identified in the tumor cells. The present lesion was a primary neuroendocrine carcinoma of the posterior mediastinum-an unusual site for such a lesion.     

Epithelioid inflammatory myofibroblastic sarcoma with recurrence after extensive resection: significant clinicopathologic characteristics of a rare aggressive soft tissue neoplasm

A case of epithelioid inflammatory myofibroblastic scarcoma (EIMS) developing in an 8-year-old boy who presented with a bulky intra-abdominal occupying lesion with recurrence undergoing a radical resection was reported. Histologically, the tumor cells arranged in cords, strands or sheets of round-to-epithelioid cells with a vesicular nuclear chromatin pattern, prominent nucleoli and weakly eosinophic or basophilic cytoplasm embedded in the abundant myxoid stroma with lymphocytes infiltration. They were positive for ALK, Desmin, SMA, CD30, but negative for AE1/AE3, LCA, CD2, CD3, CD5, CD7, S-100, CD34, CD31, EMA, MyoD1, and myogenin. An elevated proliferation index was demonstrated by Ki-67 comparing the first and the second lesion. Fluorescence in situ (FISH) showed the presence of chromosomal translocation involving ALK. This case show EIMS is a rare variant of inflammatory myofibroblatic tumor with aggressive biological behavior and unfavourable prognosis. To be familiar with its significant clinicopathologic characteristics could prompt us to take it into consideration when facing the relevant dieases.     

Myoid angioendothelioma of the spleen mimicking metastatic disease in a patient with rectal cancer: a radiologic-pathologic correlation

Myoid angioendothelioma of the spleen is an uncommon, benign vascular tumor that is morphologically characterized by a composite of vascular spaces and stromal cells with myoid feature. Herein, we report a case of the myoid angioendothelioma of the spleen, concurrent with rectal adenocarcinoma. A 41-year-old woman presented with hematochezia for several weeks. Grossly, the rectal mass was a 2.5 × 2-cm ulcerative fungating lesion. The splenic mass was a 2.2 × 2-cm well-circumscribed lesion. Microscopically, the rectal mass was a well-differentiated adenocarcinoma that invaded into the pericolic adipose tissue. The splenic mass was composed of slit-like vascular spaces and fascicles of elongated stromal cells. Vascular endothelial cells were immunopositive for CD31, factor VIII–related antigen, and CD34 but negative for CD8. Stromal cells were immunopositive for smooth muscle actin but negative for desmin.     

Angiosarcoma of the kidney with minute clear cell carcinomas: A case report

A case of renal angiosarcoma with minute clear cell carcinomas in a 61-year-old male is described. The tumor was clinically considered a renal cell carcinoma. The lesion, removed by nephrectomy, was an unencapsulated hemorrhagic mass measuring 8.0 cm in diameter. The tumor was histologically characterized by anastomosing vascular channels lined by cytologically atypical endothelial cells. The tumor cells reacted positively with CD31, factor-VIII related antigen, and CD34. A few minute clear cell carcinomas measuring less than 1 mm were observed in the periphery of the angiosarcoma. There was no transition between angiosarcoma and renal cell carcinoma. The patient died of a widespread disease 13 months after surgery. This tumor is considered a primary renal angiosarcoma with clear cell carcinomas and not a sarcomatoid carcinoma.     

Renal angiomyolipoma resembling gastrointestinal stromal tumor with skenoid fibers

We report an unusual case of renal angiomyolipoma occurring in 68-year-old man. The tumor lacked well-developed vascular and adipose components and was composed almost exclusively of smooth muscle cells. Numerous skenoid-like periodic acid-Schiff-positive globules were interspersed between the tumor cells; the lesion therefore closely resembled a low-grade stromal tumor of the gastrointestinal tract. The HMB45-positive/CD34-negative immunophenotype was essential for the diagnosis of angiomyolipoma. Neither gastrointestinal tumor nor any signs of tuberous sclerosis were found. This lesion should be included in the list of morphologic variations of angiomyolipoma, which may cause diagnostic difficulties.     

An undifferentiated embryonal sarcoma of the liver containing adipophilin-positive vesicles in an adult with massive sinusoidal invasion

Undifferentiated embryonal sarcoma of the liver (UESL) is a malignant mesenchymal tumor that occurs typically in children and rarely in adults. Here we describe a case of UESL in a 51-year-old woman who presented with a cystic lesion in the liver. Because it grew slowly, the anterior segment of the liver was resected to check the lesion. Histologically, the lesion looked like a telangiectatic hepatic adenoma. Two years after resection, the tumor recurred, and she died 3 years later due to liver failure. The autopsy revealed that these lesions were UESL with massive sinusoidal invasion, and a review of the case indicated the primary lesion was also UESL. We also confirmed these tumor cells by staining with CD56, alpha-smooth muscle actin (SMA), and adipophilin, suggesting that they have a character similar to that of stellate cells in the space of Disse. The histological result of our patient revealed atypical UESL. Therefore, UESL should be considered when a hepatic lesion with degeneration is seen, even in an adult. In addition, the immunohistochemical appearance of this case implies that UESL is perhaps derived from stellate cells or stellate cells with myofibroblast differentiation in the space of Disse.     

Solitary fibrous tumor of the pancreas

A 67-year-old woman was found to have an incidental pancreatic mass on computed tomographic examination of her abdomen in the course of investigation of hematuria. The radiologic features were of a hypervascular mass in the uncinate process of the head of the pancreas, and a preoperative diagnosis of a neuroendocrine tumor was favored. A Whipple procedure was performed. The uncinate process contained a 2.6-cm well-circumscribed mass. Histologic evaluation showed a lesion composed of alternating hypercellular areas made up of spindle-shaped cells and hypocellular areas with hyalinized, keloidal-like fibrous tissue. Occasional dilated vascular channels and entrapped pancreatic tissue were present within the lesion. Immunohistochemistry showed the lesion to be CD34, CD99, and bcl-2 positive. No evidence of atypia was noted, and the overall impression was of a benign solitary fibrous tumor of the pancreas. This is an unusual primary spindle cell neoplasm of the pancreas and should be considered in the differential diagnosis of all spindle cell lesions that occur in the pancreas.     

后肾间质肿瘤的病理观察

目的观察后肾间质肿瘤的临床病理表现,探讨其有病理诊断价值的组织学特征。方法对2例后肾间质肿瘤进行HE染色及免疫组织化学染色（EnVision法）,并进行观察。结果后肾间质肿瘤为单侧性肾占位,肿瘤位于肾髓质,边界清,呈“扇贝形”与相邻肾组织连接。镜下主要表现为：肿瘤内可见单个的肾小球和肾小管,梭形或星形肿瘤细胞呈“葱皮样”围绕肾小管和肾血管排列,细胞分布不均匀,在低倍镜下形成“结节样”图像;大部分肿瘤中内陷的小血管壁发育不良。肿瘤细胞CD34阳性表达。结论近肾小管区细胞和血管组成的“结节样”图像和CD34阳性是具有诊断和鉴别诊断价值的组织学特征。     

Lymph node interdigitating cell sarcoma. A case report.

A 54-year-old man was admitted because of right supraclavicular lymphadenopathy of some weeks duration. Computed axial tomography revealed a large multinodular lesion in a supraclavicular lymph node. The patient then had a supraclavicular lymph node biopsy. Light microscopy showed a tumor whose structure was suggestive of an interdigitating cell sarcoma. Enzyme and immunohistochemical analysis showed that the tumor cells possessed membranous adenosine triphosphatase activity, intracytoplasmic S100 protein, surface CD1a and CD4 antigens, and HLA-DR antigen. Ultrastructural examination showed that the cells exhibited many interdigitating cytoplasmic extensions, but no Birbeck granules. DNA content analysis of the tumor cells proved that the cells were malignant. These data are consistent with derivation from a lymph node interdigitating cell.     

A case of blastic plasmacytoid dendritic cell neoplasm: Cytomorphological findings of the touch imprint specimen of lymph node

The patient is a 75‐year‐old man with axillary lymphadenopathy presenting an indurated papule on his buttock. Touch imprint cytology of the biopsied axillary lymph node revealed the monotonous appearance of medium‐sized tumor cells. The nuclei had a slightly irregular contour, finely dispersed chromatin, and a conspicuous nucleolus. Some tumor cells had intracytoplasmic microvacuoles. Immunohistochemistry of the imprint specimens showed that the tumor cells were positive for CD56 and CD123. Histological diagnosis of the lesion was blastic plasmacytoid dendritic cell neoplasm (BPDCN). Epstein‐Barr virus‐encoded RNAs were not detected in the tumor cells. Neither immunoglobulin heavy chain genes nor T‐ cell receptor genes was clonally rearranged. BPDCN should be strongly considered during the differential diagnosis of CD56‐positive neoplasms of the skin. We demonstrated a possible contribution of the cytomorphological and immunohistochemical findings of the touch imprint specimens to the diagnosis of BPDCN. Diagn. Cytopathol. 2013. © 2012 Wiley Periodicals, Inc.     

Follicular dendritic cell tumor of the mediastinum

Follicular dendritic cell tumor (FDT) is a rare neoplasm usually occurring in the laterocervical lymph nodes, but presentations elsewhere are also well documented. We report a case of FDT in a 48-year-old man with myasthenia gravis, in whom a slow-growing mediastinal mass that had been surgically excised manifested after 3 years with a local recurrence in the same site. The lesion was aspirated and cytology showed a tumor composed of groups of oval or elongated cells intermingled with several mature small lymphocytes. On histology, the tumor was highly cellular with abundant perivascular lymphocytic infiltration; large cells with pale, eosinophilic cytoplasm and round nuclei, arranged in fascicles often showed a storiform pattern. Occasional binucleated cells were also present. A panel of antibodies showed positivity only for CD21 and CD35, and a weak response to S-100. Electron microscopy showed that the layer cells had convoluted nuclei and elongated interdigitating processes with desmosome-like junctions. The definitive diagnosis of FDT can be concluded only with positive immunostaining for CD21 and CD35. However, in the presence of a mixed population of lymphocytes and larger eosinophilic cells the hypothesis of FDT should always be considered.     

Solitary fibrous tumor with malignant potential arising in sublingual gland

A rare case is described of a solitary fibrous tumor (SFT) with malignant potential arising in the sublingual gland. A 59-year-old man presented with a 4-month history of a slowly enlarging painless mass in the center of the floor of the mouth. The tumor was a well-demarcated, firm mass with a multicystic lesion. The tumor exhibited highly cellular areas of spindle cells with patternless architecture alternating with hypocellular areas. The tumor cells were positive for CD34 and bcl-2 as well as vimentin, and negative for epithelial, myogenic, neurogenic and histiocytic markers. The tumor cells formed multiple satellite nodules around dilated ducts in the multicystic lesion, indicating infiltrative growth. In addition, areas exhibiting higher cellularity with increased mitoses were noticed in the satellite nodules, although cellular atypia was not obvious. These findings led to a final diagnosis of SFT with malignant potential. There has been no recurrence or metastasis for 27 months after the surgery. Solitary fibrous tumor of the salivary gland must be differentiated from various spindle cell neoplasms including myogenic, peripheral nerve sheath, fibroblastic and fibro-histiocytic spindle cell neoplasms, hemangiopericytoma and myoepithelioma. In addition to characteristic morphological features, an immunohistochemical positivity for CD34 and bcl-2 may aid in the diagnosis of SFT.     

Plexiform fibrohistiocytic tumor of soft tissues and bone

Plexiform fibrohistiocytic tumor is a rare lesion which has been reported only in the dermis and subcutis so far. We present two cases in this location and an additional one localized in the proximal epiphysis of the tibia. A case with crural location showed predominance of plexiform tumorous nodes with fibrohistiocytic arrangement. The nodes were composed of spindle-shaped myofibroblasts with admixture of histiocytes and giant multinucleated osteoclast-like cells. In another case the tumor of axillary soft tissues featured mostly plexiform bundles of spindle-shaped myofibroblast-like cells reacting positively with actin and CD 68 antibodies; ultrastructurally, they contained numerous dense lysosomal inclusions with myelin figures. The bone tumor was composed of hyalinized fibroblastic component with disperse fibrohistiocytic nodes. Despite a semimalignant character of the lesion there was no recurrence in our cases during the 2-6 year postoperative period.