[Male genitourinary system lymphoma: a clinicopathological analysis].

OBJECTIVE: To investigate the clinicopathological features and immunophenotypes of male genitourinary system lymphoma. METHODS: We retrospectively studied the histopathological characteristics and immunohistochemical markers of 35 cases of male genitourinary system lymphoma, and reviewed the relevant literature. RESULTS: The 35 patients of male genitourinary system lymphoma were aged from 4 to 83 (mean 56.5) years, 28 (80%) of them > or = 50 years. Twenty-eight cases (80%) involved the testis, 3 (8.6%) the prostate, 1 (2.9%) the spermatic cord, 1 the seminal vesicles, 1 the penis and 1 the epididymis. Histologically, 22 cases (62.9%) were diffused large B cell lymphoma (DLBCL), 6 (17.1%) mucosa associated lymphoid tissue (MALT) lymphoma, 4 (11.4%) Burkitt lymphoma, 2 (5.7%) peripheral T cell lymphoma, and 1 (2.9%) plasmacytoma. CONCLUSION: Male genitourinary system lymphomas are rare tumors clinically, which occur more often in the elderly. The majority of them are B cell lymphomas, of which the most common is DLBCL, followed by MALT lymphoma and Burkitt lymphoma. T cell lymphoma and plasmacytoma are rare. The diagnosis of male genitourinary system lymphoma relies on the histopathology, and immunohistochemical markers are of high value for its definite diagnosis, classification and differential diagnosis.

Primary kaposiform hemangioendothelioma of a long bone: two cases in unusual locations with long-term follow up.

Kaposiform hemangioendothelioma (KHE) is a rare vascular neoplasm of low malignant potential that mainly affects infants and adolescents. The tumor almost exclusively occurs in somatic soft tissue or the retroperitoneum. We report herein two cases of primary KHE occurring in a long bone without cutaneous changes with long-term follow up in young patients. The patients were a 9-year-old girl and 5-year-old boy presenting with lytic lesions of the femur and humerus, respectively, without cutaneous lesions. Histologically, the neoplasms were comprised of nodules of spindle- to oval-shaped cells growing in an infiltrative fashion. The neoplastic cells formed poorly canalized or slit-like blood vessels alternating with solid spindle areas. Immunohistochemical studies showed that the tumor cells expressed CD31, CD34 and Fli1, but not HHV8, LNA-1 or GLUT1. D2-40 stained the neoplastic spindle cells and lymphatic channels adjacent to vascular lobules. The girl remains well with 15 years and 6 months follow up after a second complete excision. The boy has no signs of recurrence or metastasis nearly 5 years after local complete excision. To our best knowledge, this is the first report in the English literature of primary long bone occurrences of KHE without cutaneous changes with long-term follow up.

[Mucinous tubular and spindle cell carcinoma of kidney: a clinicopathological study].

OBJECTIVE: To investigate the clinicopathological features, histogenesis and prognosis of mucinous tubular and spindle cell carcinoma (MTSCC). METHODS: Five MTSCCs were studied with histochemical, immunohistochemical staining, electron microscopy, and review of the related literatures. RESULTS: Four cases of MTSCC were females and one was male. Three patients presented with flank discomfort and two were incidentally found with health examination. In gross examination, the tumors were circumscribed. The cut surface was solid, gray-white, yellow or red. Necrosis was present in one case of high-grade MTSCC. Microscopically, low-grade MTSCC was mainly consisted of tubular, spindle cell and mucinous stroma with relatively bland morphology, and mitoses were rare. While in the high-grade area of one case, the cells were spindle or polymorphic with severe atypia and high mitotic activity, without mucinous stroma and tubular structure. Mucin was positive for Alcian blue. The neoplastic cells were positive for vimentin (5/5), CKpan (5/5), CK7 (5/5), CK19 (5/5), 34betaE12 (1/5), EMA (5/5), E-cadherin (3/5), CD10 (1/5), P504S (5/5), and CAM5.2 (5/5). The Ki-67 index was low (< or = 5%) in the low-grade component, while it was high (15%) in the high-grade component. Ultrastructural study showed short microvilli along glandular lumens. The nuclear membrane was focally invaginated. Four cases were followed up for 3 to 52 months, and recurrence and metastasis were not found. CONCLUSIONS: MTSCC occurs predominantly in females and it is a rare kidney neoplasm. Most of MTSCCs are low-grade and the prognosis is relatively good. However, the patients of high-grade MTSCC should be closely followed up.

[Expression of ID3 protein in prostate cancer and its clinicopathological significance].

OBJECTIVE: To study the expression of the ID3 protein in prostate cancer and its clinicopathological significance. METHODS: We detected the expression of the ID3 protein in PC-3M cells by indirect immunofluorescence, and that in 29 prostate cancer and 15 prostate hyperplasia specimens by immunohistochemistry. Then we analyzed the correlation between the expression level of ID3 and the clinicopathological parameters. RESULTS: The ID3 protein was expressed predominantly in the nucleus of PC-3M cells. Its expression rate was 82.7% (24/29) in the prostate cancer specimens, significantly higher than 6.6% (1/15) in prostate hyperplasia (P < 0.05), and was positively correlated with the Gleason score of prostate cancer (P < 0.05). CONCLUSION: The ID3 protein is expressed in prostate cancer, and is elevated with the increase of Gleason score.

[Clinicopathological analysis of testicular mixed germ cell tumor].

OBJECTIVE: To investigate the clinicopathological characteristics of primary testicular mixed germ cell tumor (MGCT). METHODS: We retrospectively analyzed the clinicopathological data of 13 cases of primary testicular MGCT and reviewed other relevant literature. RESULTS: MGCT accounted for 24.1% (13/54) of all the testicular germ cell tumors diagnosed in our hospital. The patients ranged in age from 2 to 53 years, averaging at 28.3 years. All were unilateral cases, 6 in the left and 7 in the right testis, with a left/right ratio of 0.86:1. Morphologically, testicular MGCT displayed a variety of subtypes, embryonal carcinoma in 11 cases (84.6%), seminoma in 8 (61.5%), teratoma in 6 (46.2%), choriocarcinoma in 4 (30.8%) and yolk sac tumor in 4 (30.8%). Nine of the cases (69.2%) were composed of two different germ cell histological elements, 3 (23.1%) composed of three, and 1 (7.7%) composed of five. CONCLUSION: Testicular MGCT is rather rare and most commonly occurs in young men. Its biological behavior, clinical management and prognosis vary with its different histological elements. Therefore accurate pathological diagnosis is essential and immunohistochemistry plays an important role in the diagnosis and differential diagnosis of testicular MGCT.

Expression analysis of Wnt-5a in renal epithelial neoplasms: distinguishing renal oncocytoma from a wide spectrum of renal cell carcinomas.

OBJECTIVE: To study the expression of a novel marker, Wnt-5a, in renal epithelial neoplasms and determine its clinicopathological significance. METHODS: Immunohistochemical analysis of Wnt-5a was carried out in normal human kidney samples as well as in 123 primary renal epithelial neoplasms including 37 clear cell renal cell carcinomas (RCCs), 24 papillary RCCs (15 type 1 and 9 type 2), 25 chromophobe RCCs, 11 Xp11 translocation carcinomas, 6 mucinous tubular and spindle cell carcinomas, and 20 oncocytomas. RESULTS: Wnt-5a was expressed in 18.9% (7/37) of clear cell RCCs, 12.5% (3/24) of papillary RCCs, 16% (4/25) of chromophobe RCCs, 18.2% (2/11) of Xp11 translocation carcinomas, 0% (0/6) of mucinous tubular and spindle cell carcinomas, and 100% (20/20) of oncocytomas. There was a significant difference in Wnt-5a immunohistochemistry between renal oncocytoma and the other subtypes of RCC (P < 0.01). CONCLUSIONS: Our results indicate that Wnt-5a is a potentially useful immunohistochemical marker for the complex differential diagnosis between oncocytoma and other subtypes of RCC and also suggest that Wnt-5a may be a tumor suppressor gene in RCC.

[Expression of CD20 in thymomas and its clinical implication].

OBJECTIVE: To study the expression of CD20 in thymomas and its clinical significance. METHODS: One hundred and seventy-nine cases of thymoma were enrolled into the study. The histologic diagnosis was reviewed by two experienced pathologists on the basis of the 2004 WHO classification. One hundred and two cases were selected for immunohistochemical study for CD20, pancytokeratin, TdT, CD3, CD43, CD99 and S-100 protein. The cases were further categorized into two groups, according to the association with clinical evidence of myasthenia gravis. The immunostaining pattern was then statistically analyzed. RESULTS: Amongst the 102 cases studied, 7 cases belonged to type A thymoma, 32 cases type AB thymoma, 17 cases type B1 thymoma, 15 cases type B2 thymoma, 17 cases type B3 thymoma and 14 cases thymic carcinoma. The expression rates of CD20 in neoplastic epithelial cells of type A, type AB, type B1, type B2 and type B3 thymomas and thymic carcinomas were 3/7, 84.4% (27/32), 1/17, 2/15, 0/17, 0/14, respectively. The proportions of CD20-positive lymphocytes in the background were 3/7, 18.8% (6/32), 14/17, 11/15, 11/17, 6/14, respectively. The proportion of CD20-positive intra-tumoral B lymphocytes in the group of thymomas with myasthenia gravis was 67.5% (22/40), in contrast to 35.5% (22/62) in those without myasthenia gravis. CONCLUSIONS: The neoplastic epithelial cells in cases of type A and type AB thymoma, as well as few cases of type B1 and B2 thymoma, express CD20. The immunostain highlights the presence of oval, stellate or spindly cells. Thymomas associated with myasthenia gravis contain a significant population of CD20-positive intra-tumoral B lymphocytes. Type AB thymomas may be originated from different populations of cells, rather than a simple admixture of type A and B thymoma cells.

[Clinicopathologic features of granulocytic sarcoma: a study of 38 cases].

OBJECTIVE: To study the clinicopathologic features of granulocytic sarcoma. METHODS: The clinical and pathologic findings of 38 cases of granulocytic sarcoma were retrospectively analyzed. Immunohistochemical study was performed and the literature was reviewed. RESULTS: The age of patients ranged from 2 to 77 years (mean = 43.3 years). The male-to-female ratio was 1.5:1. Major clinical presentations included superficial lymph node enlargement and painful soft tissue mass. Follow-up data were available in 18 patients; and 14 of them died of tumor-related diseases. The average duration of survival of the patients was 16.9 months. Histologically, the tumor cells were relatively uniform in appearance and small to medium in size. The cytoplasm was scanty and pale in color. The nuclei were round or focally irregular, with fine chromatin and inconspicuous nucleoli. Mitosis figures were readily identified. Scattered immature eosinophilic myelocytes were seen. Immunohistochemical study showed that the tumor cells in all cases expressed MPO and CD43. Most cases were also positive for CD68, lysozyme, CD99 and TdT. The staining for CD3, CD20, CD79a, pan-cytokeratin and PLAP were negative. CONCLUSIONS: Granulocytic sarcoma is a known histologic mimicker of non-Hodgkin lymphoma, Ewing sarcoma/PNET and embryonal rhabdomyosarcoma. Detailed morphologic examination, when coupled with immunohistochemical study, is useful in arriving at a correct diagnosis.

[Clinicopathologic and molecular genetic study of renal cell carcinoma occurring in teenagers].

OBJECTIVE: To investigate clinicopathological features, molecular genetic characteristics, differential diagnoses and prognosis of renal cell carcinoma in teenagers. METHODS: Microscopic and immunohistochemical features of 46 cases of renal cell carcinomas in teenagers were reviewed along with the clinical follow-up data. Loss of heterozygosity (LOH), analysis of von Hippel-Lindau (VHL) gene and screening for VHL gene mutations were performed in all of the tumors. RESULTS: There were 19 Xp11.2 translocations/TFE3 gene fusions renal clear cell carcinomas (Xp11 RCCs), 9 chromophobe renal cell carcinomas (CCRCCs), 17 papillary renal cell carcinomas (PRCCs), and 1 unclassified renal cell carcinoma (RCC). All of the 19 Xp11.2 translocation RCCs showed a moderate to strong immunoreactivity for TFE, however, no TFEB expression was obtained. There were 4 histological patterns in the Xp11 RCC cases including: 8 tumors possessing a nested to papillary architecture resembling to the t(X;17) ASPL-TFE3 phenotype; 6 tumors possessing a morphologic feature like the t(X;1) PRCC-TFE3 phenotype; 4 cases morphologically resembling to clear cell RCC; and 1 Xp11 RCC case, with a special morphologic feature not searched yet in the literature, including a ground glass appearance of the nuclei accompanying occasionally with grooves on the nuclear surface; nucleoli inconspicuous with accumulation of abundant mucin-like substance in the stroma. VHL gene analysis revealed deletions at 3p25-26 in one clear cell RCC and one papillary type 2 RCC. The papillary type 2 RCC had also a family history of VHL disease, with a germline G→C mutation at a splicing site of position 553+5. There were no VHL mutations detected in the remaining 45 RCCs. Statistical analysis of tumor stage and outcome revealed that TFE+ RCCs of teen-agers were more frequently associated with a higher pT3/pT4 stage and a poorer outcome than that of the TFE-RCCs (P < 0.05). CONCLUSIONS: RCCs of the teenagers have a different morphologic spectrum and genetic background from the RCCs seen in adults. Among RCCs of the teen-agers, Xp11.2 translocation tumors are the most common RCCs and have a poorer prognosis than that of the TFE-RCCs.

[Clinicopathologic study of von Hippel-Lindau syndrome-related and sporadic hemangioblastomas of central nervous system].

OBJECTIVE: To study clinicopathologic features, diagnosis, treatment and prognosis of von Hippel-Lindau (VHL) syndrome-related and sporadic hemangioblastomas of the central nervous system (CNS-HB). METHODS: Histopathological, ultrastructural, immunohistochemical (EnVision method) and clinical features of 21 VHL syndrome and 63 sporadic CNS-HB cases were studied with correlation of the available follow-up information. RESULTS: Twenty-one VHL patients accompanied with a total of 87 CNS-HBs, including one patient of developing 12 HBs within 13 years. There were 10 patients presenting other lesions related to VHL, including 6 retinal HBs, 4 pancreatic tumors (endocrine tumor and microcystic cystadenoma), 1 clear renal cell carcinoma, 4 renal cysts and 1 endolymphatic sac tumor. One patient developed 5 different tumors related to VHL within a period of 4 years. In the 63 cases of sporadic CNS-HB (34 male and 29 female), the mean age was 43.0 years. Among the 18 VHL syndrome patients with available follow-up information, 14 were still alive and within them, 4 became disabled and 11 had developed new lesions. The other 4 patients died. Among the 42 patients of sporadic HB with follow-up information, 39 were alive including 3 disabled cases, and the other 3 died. Histologically, the tumors showed large and vacuolated stromal cells. Some tumors showed atypical nuclei. Involvement of the brain tissue was seen in 32 cases, among which, 21 patients with available follow-up information were learnt to be alive. Tumor cells of HB stained positive for vimentin, EGFR, Inhibin alpha and D2-40, but negative for CD34 and CD68. In 3 cases of HB, some stromal cells were positive for GFAP. All cases showed a low expression for Ki-67, except 2 cases with 2% and 1 case with 5% Ki-67 indices. CONCLUSIONS: VHL syndrome is a multisystem disorder with a poor prognosis and a high rate of missed diagnosis. The syndrome is characterized by development of various benign and malignant tumors. The most common tumor is CNS-HB, which occurs predominantly in the cerebellum. Patients with VHL syndrome tend to present at a younger age than patients with sporadic CNS-HBs, and VHL related HB occurs more predominantly in the brain stem and spinal cord. Prognosis of CNS-HB patients is not correlated with the nuclear atypicality, expression for Ki-67 and involvement of the brain tissue. Because new lesions may develop during the patient's lifetime. So that, regular clinical inspection is recommended in order to check up the development of any new lesions.

[Expression and clinical significance of kidney injury molecule-1 in renal epithelial neoplasms].

OBJECTIVE: To study the expression and clinical significance of kidney injury molecule-1 (KIM-1) in primary and metastatic renal epithelial neoplasms. METHODS: A total of 136 cases of kidney neoplasms were retrospectively reviewed including 63 primary clear cell renal cell carcinomas (RCCs), 22 papillary RCCs, 13 chromophobe RCCs, 7 oncocytomas, 7 RCCs associated with Xp11.2 translocation/TFE3 gene fusions and 24 metastatic clear cell RCCs. Immunostaining for KIM-1 and kidney-specific-protein (Ksp)-cadherin were performed and the relationship to tumor stage and grade in clear cell RCCs was investigated. RESULTS: Expression of KIM-1 was detected in 77.8% (49/63) of clear cell RCCs, 90.9% (20/22) of papillary RCCs, 1/13 of chromophobe RCCs, 7/7 of RCCs associated with Xp11.2 translocation/TFE3 gene fusions and 87.5%(21/24) of the metastatic RCCs, but not detected in 7 cases of oncocytomas. A diffuse expression of KIM-1 was more frequently observed in Furhman nuclear grade III/IV clear cell RCCs (P = 0.010). Ksp-cadherin expression was mainly observed in chromophobe RCCs and oncocytomas. CONCLUSIONS: KIM-1 is a specific biomarker for injuried kidney proximal tubules and the corresponding neoplasms, and has a high specificity and sensitivity for primary or metastatic clear cell RCCs, papillary RCCs and RCCs associated with Xp11.2 translocation/TFE3 gene fusions. Combination of KIM-1 and Ksp-cadherin immunostaining can lead to a more precise histological classification of primary kidney epithelial neoplasms and improve the diagnostic accuracy of metastatic RCCs.

[Clinicopathological study of 5 cases of proximal-type epithelioid sarcoma].

OBJECTIVE: To investigate the clinicopathological characteristics, diagnosis and differential diagnoses of proximal-type epithelioid sarcoma (PES). METHODS: Five cases of PES were retrieved from pathology files. Clinical, pathologic and immunohistochemical features of the tumors were reviewed. RESULTS: One patient was female and 4 were male. Ages of the patients ranged from 19 to 46 years. The sites of the tumor involvement were vulvar (2 cases), hypogastric zone (1 case), anterosuperior iliac spine (1 case) and buttock (1 case). Clinically, the tumor masses were painless and progressive solitary nodules. Microscopically, the tumor cell growth was infiltrative in nature, nodular in appearance with degenerative and necrotic cells at the central areas. The tumors consisted of relatively uniform epithelioid cells with round or oval nuclei and eosinophilic cytoplasm. Immunohistochemically, the tumor cells were positive for vimentin (5/5), CK (4/5), EMA (4/5), beta-catenin (3/5), CD34 (3/5), and S-100 protein (1/5), but were negative for SMA, MyoD1, Desmin, HMB-45, CK7 and CK20. CONCLUSION: Definitive diagnosis of PES relies on its histopathological characteristics in conjunction with appropriate immunohistochemical findings.

[Primary Burkitt lymphoma of the seminal vesicle: a case report and review of the literature].

OBJECTIVE: To investigate the clinicopathological features of primary Burkitt lymphoma of the seminal vesicle. METHODS: We reported the clinical characteristics, histological changes and the results of immunohistochemical staining and molecular in situ hybridization of 1 case of primary Burkitt lymphoma of the seminal vesicle. We also reviewed the related literature and studied the pathomorphological characteristics and differential diagnosis of the tumor. RESULTS: The characteristic manifestations of the patient were frequent micturition with dysuria, followed by inguinal lymphadenectasis 2 months later. Medical imaging showed a diffuse and monotonous infiltration of neoplastic cells with scanty cytoplasm and a few mitosis images. Microscopy displayed a starry sky pattern. The tumor cells were positive for CD10, CD20, CD79alpha, Bcl-6 and EBER in situ hybridization, but negative for CD3, CD6 and Cyclin D1. The Ki-67 index was > 95%. CONCLUSION: Primary Burkitt lymphoma of the seminal vesicle is a very rare tumor with aggressive behavior. The pathological diagnosis of the tumor depends on histopathological examination and immunohistochemical techniques. However it should be differentiated from diffuse large B-cell lymphoma, lymphoblastic lymphoma and small cell carcinoma of the seminal vesicle or prostate gland.

[Follicular dendritic cell sarcoma: a clinicopathologic study of 8 cases].

OBJECTIVE: To investigate clinicopathologic features, immunophenotypes and differential diagnoses of follicular dendritic cell sarcoma/tumor (FDCS). METHODS: Eight cases of FDCS were studied using histological and immunohistochemical examinations and EBER in situ hybridization, with a review of the related literatures. RESULTS: There were 5 male and 3 female patients with a median age of 50 years. The sites of involvement included lymph node (4 cases), tonsil, nasopharynx, liver, and spleen (1 case each, respectively). The predominant microscopic features histologically included storiform, fascicular, diffuse, whorled and nodular in patterns. The neoplastic cells, dispersed by the infiltrated small lymphocytes, were characterized by abundant eosinophilic or fine granular cytoplasm with indistinct cell borders, and syncytial in appearance. The nuclei of the tumors were ovoid, round to spindled in shape with vesicular or stippled chromatin and small distinct nucleoli. Mitotic figures varied among cases. Pseudovascular spaces and perivascular cuffing were observed in some cases. One case of FDCS involving lesion in liver showed a background of abundant lymphocytes mixing with dispersed spindle or ovoid neoplastic cells having delicate chromatin, mild nuclear atypia, irregular/vesicular nuclei and distinct nucleoli. The neoplastic cells were positive for CD21, CD35, clusterin, and weakly positive for CD68, EMA, S-100 and EGFR. Ki-67 stain showed a variable expression among cases. EBER was positive in 2 cases. CONCLUSIONS: FDCS is a rare malignant tumor with a tendency to relapse and metastasis. Combined morphological and immunophenotypical analysis is necessary to reach a correct diagnosis.

[Clinicopathologic study of pilocytic astrocytoma].

OBJECTIVE: To study clinicopathologic features, treatment and prognosis of pilocytic astrocytoma (PA). METHODS: Histopathological, ultrastructural, immunohistochemical (EnVision method) and clinical features of 68 cases of PA were studied by microscopic investigation with correlation of clinical follow-up information when available. RESULTS: Thirty-five male patients and 33 female patients were studied. The patient's age ranged from 3 to 66 years (mean = 20.1 years). The mean time from symptom onset to surgery was 371 days (range, 3 days to 14 years). Cystic degeneration was noted in 41 cases (60.3%), and enhancement of the tumor was noted in 43 cases (87.8%). On postcontrast imaging examination there were 33 cases involving the cerebellum (48.5%). Total tumor excision was performed in 35 patients, subtotal tumor excision was performed in 31 patients, and the procedures of other 2 patients were not clear. Among 51 patients with follow-up information, 44 were alive, 7 had recurrent tumor, and 7 died. The post-operative survival ranged from 2 months to 124 months (mean survival = 48.1 months). Five years and ten years survival rates were 89%, respectively. Tumors with classic histopathology demonstrated biphasic pattern of growth, consisting of compact elongated bipolar astrocytes associated with rosenthal fibers, and less cellular areas of multipolar cells with granular bodies and microcyst. Some cases showed atypia of nuclei, and occasional mitoses. Involvement of subarachnoid space was seen in 17 cases. One case had anaplastic features. All cases showed diffuse positive staining for GFAP and low expression for Ki-67, except 1 anaplastic tumor with 10% Ki-67 indices. Tumors with subarachnoid space involvement showed positive reticular fiber staining and negative EMA staining. CONCLUSIONS: PA is a benign, WHO grade I tumor with favorable prognosis, and does not require radiotherapy after total resection. The tumor can be mistaken as higher-grade astrocytoma when involving the subarachnoid space, and with cytological atypia, leading to unnecessary radiotherapy after surgery. Recurrence rate is increased when only partial resection is achieved. The outcome for patients with brainstem tumor or anaplastic PA is poor.

[Primary diffuse large B-cell lymphoma of central nervous system belongs to activated B-cell-like subgroup: a study of 47 cases].

OBJECTIVE: To investigate the histogenetic origin of primary central nervous system diffuse large B-cell lymphoma (DLBCL) with respect to the stage of B-cell differentiation, and identification of the relevant prognostic markers. METHODS: Immunohistochemical staining (EnVision method) for CD10, bcl-6, MUM-1, CD138 and FOXP1 antigens was performed on 47 paraffin-embedded sections. RESULTS: CD10, bcl-6, MUM-1 and FOXP1 expression in the tumor cells were 6.4%, 53.2%, 91.5% and 93.6% respectively. There was no expression of CD138 in all the cases. Among the 47 patients, 43 cases (91.5%) showed an activated B-cell-like (ABC) phenotype: 21 (44.7%) were bcl-6+ and MUM-1+, suggesting an "activated germinal center (GC) B-cell-like" in origin; 22 (46.8%) were exclusively MUM-1+, suggesting an "activated non-GCB" in origin. No significant correlation of the classification and FOXP1 expression found on the outcome (P=0.279 and P=0.154). CONCLUSIONS: Most primary central nervous system DLBCL are shown belonging to the ABC subgroup, suggesting that primary central nervous system DLBCL is quite similar to a DLBCL subset, which is derived from late GC to early post-GC B cell. The classification and FOXP1 expression do not show prognostic value in primary central nervous system DLBCL.

[Clinicopathological analysis of Paget's disease of the scrotum and penis].

OBJECTIVE: To investigate the clinical pathological characteristics, diagnosis and differential diagnosis of Paget's disease of the scrotum and penis. METHODS: Thirteen cases of Paget's disease of the scrotum and penis were analyzed by light microscopy, alcian-blue (AB)/periodic-acid-Schiff (PAS) and immunohistochemical staining. RESULTS: Paget's disease of the scrotum and penis mainly affected old individuals aged 55-84 (mean 71) years. Macroscopically, typical presentations of Paget's disease of the scrotum and penis were eczematoid lesions. Microscopically, Paget cells were distributed singly or in groups (as strands, nests or glandular patterns) within the epidermis. Paget cells were typically stained for AB/PAS, positive for CK7, CEA and EMA, and negative for CK5/6, S-100 and P63. The positive rates of GCDFP-15 and CK20 expressions were 76.92% (10/13)and 53.85% (7/13) respectively. CONCLUSION: Paget's disease of the scrotum and penis is a low-malignancy cutaneous tumor with typical clinical and pathological features. Pathologic diagnosis is based on immunohistochemical findings.

[Primary peripheral T-cell lymphoma of the penis: a case report and review of the literature].

OBJECTIVE: To report a case of primary peripheral T-cell lymphoma of the penis. METHODS: We analyzed the clinicopathological characteristics of the case of primary peripheral T-cell lymphoma using histological, cytochemical and immunohistochemical methods and by review of the literature. RESULTS: The patient was a 65 years old man and presented with a diffuse enlargement of the penis as the initial sign, followed by erosive ulcer in the caput penis and inguinal lymphadenectasis. The tumor was pathohistologically manifested as an epidermal ulcer, with tumorous necrosis around the capillary, infiltrative growth and atypical changes of the neoplastic cells and proliferation of capillaries. Immunohistochemically, the tumor cells were positive for CD43 and CD3, but negative for CD20, CD79a, CD34, CD30, CD56 and CD34. Clinically it responded to the chemotherapy designed for peripheral T-cell lymphoma. CONCLUSION: Primary peripheral T-cell lymphoma of the penis is an extremely rare malignant tumor, the diagnosis of which relies on histopathological examination, immunohistochemical staining and differentiation between squamous cell carcinoma and other types of lymphoma.

[Burkitt's lymphoma of the spermatic cord: a case report and review of the literature].

OBJECTIVE: To investigate the clinicopathological characteristics of primary Burkitt's lymphoma (BL) in the spermatic cord. METHODS: A case of BL of the spermatic cord was studied by histopathology and immunohistochemical techniques. The clinical data and the related literature were reviewed. RESULTS: The patient was a 4-year-old boy, who was accidentally found with a bump in the scrotum. Surgery showed it to be a tumor located in the left spermatic cord and 5 cm x 3 cm x 2 cm in size, gray and fish-like on cross-sectional imaging. Histologically, it was characterized by monotonous infiltration of medium-sized cells with round nuclei, coarse chromatin, 2-5 basophilic nucleoli, and an appreciable rim of basophilic cytoplasm, in a typically starry-sky pattern imparted by interspersed tangible-body macrophages. Immunohistochemically, the tumor cells were diffused, positive for CD20 and CD79, some for CD10 and about 95% with the nuclear expression of Ki-67, but negative for CD3, CD43, bcl-2 and TdT as well as for EBER in situ hybridization. CONCLUSION: Primary spermatic cord BL is extremely rare, highly aggressive and with poor prognosis. Diagnosis of the tumor relies on its pathological characteristics and immunohistochemical staining. It is essential to differentiate BL from other types of lymphomas and malignant small-cell tumors of the non-lymphatic system.