Two microRNA panels to discriminate three subtypes of lung carcinoma in bronchial brushing specimens.

RATIONALE: Effective treatment for lung cancer requires accuracy in subclassification of carcinoma subtypes. OBJECTIVES: To identify microRNAs in bronchial brushing specimens for discriminating small cell lung cancer (SCLC) from non-small cell lung cancer (NSCLC) and for further differentiating squamous cell carcinoma (SQ) from adenocarcinoma (AC). METHODS: Microarrays were used to screen 723 microRNAs in laser-captured, microdissected cancer cells from 82 snap-frozen surgical lung specimens. Quantitative reverse-transcriptase polymerase chain reaction was performed on 153 macrodissected formalin-fixed, paraffin-embedded (FFPE) surgical lung specimens to evaluate seven microRNA candidates discovered from microarrays. Two microRNA panels were constructed on the basis of a training cohort (n = 85) and validated using an independent cohort (n = 68). The microRNA panels were applied as differentiators of SCLC from NSCLC and of SQ from AC in 207 bronchial brushing specimens. MEASUREMENTS AND MAIN RESULTS: Two microRNA panels yielded high diagnostic accuracy in discriminating SCLC from NSCLC (miR-29a and miR-375; area under the curve [AUC], 0.991 and 0.982 for training and validation data set, respectively) and in differentiating SQ from AC (miR-205 and miR-34a; AUC, 0.977 and 0.982 for training and validation data set, respectively) in FFPE surgical lung specimens. Moreover, the microRNA panels accurately differentiated SCLC from NSCLC (AUC, 0.947) and SQ from AC (AUC, 0.962) in bronchial brushing specimens. CONCLUSIONS: We found two microRNA panels that accurately discriminated between the three subtypes of lung carcinoma in bronchial brushing specimens. The identified microRNA panels may have considerable clinical value in differential diagnosis and optimizing treatment strategies based on lung cancer subtypes.

[Screening of differentially expressed microRNAs in borderline and malignant gastrointestinal stromal tumors].

OBJECTIVE: Gastrointestinal stromal tumors (GISTs) have a broad spectrum of biological behaviors ranging from benign, borderline and malignant. This study aimed to screen differentially expressed microRNAs (miRNAs) between malignant and borderline GISTs and to investigate the potential role of miRNAs in the malignant transformation of GISTs. METHODS: Six GIST samples including borderline tumors (n = 3) and malignant tumors (n = 3) were collected based on the clinical and pathological characteristics. Total RNA was extracted, followed by miRNA microarray analysis to screen the differentially expressed miRNAs. The most significantly expressed 4 miRNAs were then chosen for further validation by real-time PCR in 22 additional GIST samples. RESULTS: Direct comparison of malignant group versus borderline group revealed 14 significantly and differentially expressed miRNAs (P < 0.05, with a fold change of < 0.5 or > 2). Five miRNAs were up-regulated and nine were down-regulated in the malignant group. Four miRNAs (miR-221, miR-135b, miR-675(*) and miR-218) were most significantly and differentially expressed between the two groups. The differential expression of 2 miRNAs (miR-221 and miR-675(*)) were subsequently confirmed with good concordance by real-time PCR. CONCLUSIONS: The differential miRNA expression profiles between two groups are revealed by miRNA microarray assay, and confirmed by real-time PCR. Among differentially expressed miRNAs, miR-221 and miR-675(*) might be related to the malignant transformation of GISTs, and have a potential value in predicting biological behavior of GISTs.

IRF4 rearrangement may predict favorable prognosis in children and young adults with primary head and neck large B-cell lymphoma.

PURPOSE: Large B-cell lymphoma with IRF4 rearrangement (LBCL, IRF4+) has been recently recognized as a specific entity that is frequently associated with young age and favorable prognosis. However, whether the good outcome of the disease is due to IRF4+ or other factors remains obscure. We thus analyzed 100 young patients with primary head and neck LBCL to see the clinicopathologic correlates of IRF4+. METHODS: The histopathology, immunophenotype, IRF4 status of the tumors, and clinical data were reviewed. RESULTS: Twenty-one tumors were diagnosed as LBCL, IRF4+, which were more frequently associated with a follicular growth pattern, medium-sized blastoid cytology, germinal center B-cell-like, and CD5+ phenotype, compared with IRF4- ones. While most of the patients received chemotherapy with or without radiation, eight IRF4+ patients received mere surgical resection of the tumor and exhibited excellent outcome. IRF4+ cases featured a significantly higher complete remission rate, and better survivals compared with IRF4- ones. Multivariate analysis confirmed IRF4+ correlates with a better survival. CONCLUSION: Our work confirmed the unique clinicopathologic features of LBCL, IRF4+, and disclosed for the first time the independent favorable prognostic impact of IRF4+. These findings may further unravel the heterogeneity of LBCL occurring in youth, and aid in risk stratification and tailoring the therapeutic strategy.

[Cytogenetic profiles of follicular lymphoma].

OBJECTIVE: To study the cytogenetic profiles of follicular lymphoma (FL) in Chinese patients. METHODS: Conventional karyotype in 57 FL patients from Shanghai area was analyzed. Fluorescence in-situ hybridization (FISH) for t(14;18) and Bcl-6 and IgH gene rearrangement was performed in these cases. RESULTS: The most frequent breakpoints (frequency > or = 10% ) of the 57 FL cases were at band 14q32 (68.4%), 18q21 (38.6%), 3q27 (21.1%), 1q10 (15.8%) and 1q21 (12.3%). Nineteen (33.3%) of the 57 cases had t(14;18). The breakpoint of 18q21 and t(14;18) were more frequent in FL grade 1-2 and less frequent in FL grade 3 (57.6% vs. 12.5%; 54.5% vs. 4.2%, P < 0.05), whereas the 3q27/Bcl-6 rearrangement was more frequent in FL grade 3 and less frequent in FL grade 1-2 (37.5% vs. 9.1% , P < 0.05). The cohort of FL was more frequent in gains of chromosomes X, 1q, 5, 6p, 7 and 12q and losses of chromosomes 1p, 6p and 14q32. Gain of 18q was more frequent in FL grade 1-2 than in FL grade 3 (P < 0.05). Loss of 14q32 was more frequent in t(14;18) negative FL than in t(14;18) positive FL (P < 0.05). CONCLUSIONS: Compared with the data of Western patients reported in the literature, Chinese FL cases had distinct cytogenetic profiles from Western FL cases that the t(14;18) is less frequent and the gain of 1q is more frequent in Chinese FL cases, which are more significant in high grade FL.

[Study on clinicopathologic grading system and prognosis of primary hepatic neuroendocrine neoplasms].

OBJECTIVE: To study the clinicopathologic features, criteria for grading and prognostic factors of primary hepatic neuroendocrine neoplasms. METHODS: Thirty-five cases of primary hepatic neuroendocrine neoplasm were retrieved from the archival files over a period of 11 years (with 32 cases having integrated data). According to the 2010 WHO classification of tumors of the digestive system, the cases were categorized into three groups: neuroendocrine tumor grade 1 (NET G1), neuroendocrine tumor grade 2 (NET G2) and neuroendocrine carcinoma (NEC). Statistical correlation between various histologic parameters and survival data was analyzed. RESULTS: Statistical analysis showed significant difference between NET [G1 (1 case)/G2 (14 cases)] and NEC (17 cases) groups in terms of tumor differentiation, necrosis, nuclear atypia, mitotic count and Ki-67 proliferative index (P < 0.05). There was no statistically significant difference in tumor size, growth pattern and presence of vascular tumor emboli (P > 0.05). The survival rate of patients correlated with tumor differentiation, growth pattern, necrosis, nuclear atypia, mitotic count and proliferative index (P < 0.05). There was no statistically significant difference between patient survival and tumor size or presence of vascular tumor emboli (P > 0.05). CONCLUSIONS: The subdivision of primary hepatic neuroendocrine neoplasm according to the 2010 WHO classification of tumors of the digestive system helps to evaluate the malignant potential and prognosis of the tumors. Prognostically useful histologic parameters include tumor differentiation, growth pattern, necrosis, nuclear atypia, mitotic count and proliferative index.

[Staging and histologic grading of gastrointestinal stromal tumors].

OBJECTIVE: To investigate the clinical stage and histological grade of gastrointestinal stromal tumors. METHODS: Twelve clinical and pathological parameters were assessed in 613 patients with follow-up information. These parameters were classified into two gross spread parameters including liver metastasis and peritoneal dissemination, five microscopic spread parameters including lymph node metastasis, vascular, fat, nerve and mucosal infiltration, and five histological parameters including mitotic count ≥ 10 per 50 high-power fields, muscularis propria infiltration, coagulative necrosis, perivascular pattern and severe nuclear atypia. RESULTS: The accumulated 5-year disease-free survival (DFS) and overall survival (OS) of 293 patients without any of these predictive parameters of malignancy were 99.3% and 100.0%, respectively. They were regarded as nonmalignant and further evaluations on the stage and grade of these tumors were not performed. At least one and at most seven predictive parameters of malignancy were identified in 320 patients. For these patients, the accumulated 5-year DFS and OS rates were 43.9% (mean 6.7 years) and 59.7% (mean 9.3 years), respectively. The DFS showed significant difference between patients with and without gross spread (P < 0.01), with and without microscopic spread (P = 0.001). DFS and OS were associated with the number of predictive parameters of malignancy in patients without gross spread (P < 0.01 for both DFS and OS), but not in patients with gross spread (P = 0.882 and 0.441, respectively). CONCLUSIONS: Malignant GIST could be divided into clinical stages I and II based on the absence and presence of gross spread, respectively. The degree of malignancy of patients in clinical stage I could be graded according to the number of predictive parameters of malignancy. Patients in clinical stage II were of the highest degree of malignancy regardless of the number of parameters. The staging and grading of gastrointestinal stromal tumors in this study are strongly associated with prognosis.

[Follicular variant of peripheral T-cell lymphoma: a clinicopathologic and genetic study of 2 cases].

OBJECTIVE: To observe the clinicopathologic and genetic features of follicular variant of peripheral T-cell lymphoma (FV-PTCL), with particular attention to the relationship of this type of lymphoma with angioimmunoblastic T-cell lymphoma (AITL). METHODS: The clinical data, hematoxylin and eosin-stained sections of lymph node biopsies from 2 FV-PTCL cases were reviewed. Immunohistochemical phenotyping and detection of EBV-encoded RNAs (EBER) through in situ hybridization (ISH) were performed. The EnVision two-step method was used for all antibodies except CXCL13 (by using three-step streptavidin immunoperoxidase method). Analysis of clonality and ITK/SYK gene rearrangement was conducted using PCR and RT-PCR assays, respectively. RESULTS: Clinically, the two patients presented with superficial lymphadenopathy similarly. Histologically, case 1 showed a follicular/nodular lymphoid proliferation without marked germinal centers. The neoplastic cells comprised mainly medium sized cells with abundant, sometimes clear cytoplasms. Similar histologic findings were seen in case 2 in addition to a concurrent component mimicking typical AITL noticed. Of both cases, the neoplastic cells showed positive reactivity to CD3, CD4, CD10, PD1, and CXCL13. Positive hybridization signals for EBER were only seen in case 2, and double stains demonstrated that those EBV-positive cells were mostly the reactive transformed B-cells. Monoclonal T-cell proliferation was proved by the rearranged TCR gene detection in both cases. Neither of the current cases expressed ITK/SYK fusion transcripts. CONCLUSION: FV-PTCL shows the similar or overlapped morphological and immunophenotypic features to those of AITL, possibly suggesting the presence of a potential relationship between these two types of lymphomas.

[TMPRSS2-ERG gene fusion in metastatic prostate cancers: a study of fine needle aspiration specimens].

OBJECTIVE: To investigate diagnostic values of the detection of TMPRSS2-ERG gene fusion in metastatic prostate cancer. METHODS: A total of 32 fine needle aspiration (FNA) specimens of metastatic prostate carcinomas were retrieved from the pathology files at MD Anderson Cancer Center. The metastatic sites included the pelvic and remote lymph nodes, liver, bone, and thyroid gland. Immunohistochemical staining for PSA, PAP, synaptophysin, chromogranin A was performed. TMPRSS2-ERG gene fusion was evaluated on sections of cell blocks by fluorescence in situ hybridization (FISH) using ERG gene break-apart probes. RESULTS: The mean age of the patients was 67 years. Twenty-six patients had a previous history of prostatic adenocarcinoma, while 6 patients presented initially with metastasis. In 11 patients, the metastatic lesions showed characteristic features of small cell carcinoma (SCC) and were positive for synaptophysin (9/9), chromogranin A (7/8), but negative for prostatic specific antigen (7/7). FISH analysis demonstrated a rearrangement of ERG gene in 10 of 32 cases (31.3%), and the rearrangement was associated with deletion of the 5' ERG gene in 6 cases. In addition, the copy number of ERG rearrangement gene locus was increased in 8 cases. Among the 11 cases with SCC features, a rearrangement of ERG gene was present in 5 cases, of which a deletion of the 5' ERG gene and increased copy number were seen in 3 cases. CONCLUSIONS: TMPRSS2-ERG gene fusion can be evaluated in FNA specimens of metastatic prostate cancer. Metastatic prostate cancers have a high prevalence of TMPRSS2-ERG gene fusion along with a frequent copy number increase of ERG gene. TMPRSS2-ERG gene fusion persists in metastatic prostate cancers and even in those with poorly differentiated SCC features. Therefore, an identification of the TMPRSS2-ERG gene fusion may be used to establish the prostatic origin of metastasis.

[Urothelial hyperplastic lesion with endophytic growth pattern: a clinicopathologic study].

OBJECTIVE: To study the clinicopathologic features of urothelial hyperplastic lesion with an endophytic growth pattern and the role of immunohistochemistry and multitargeted fluorescence in situ hybridization (FISH) in the differential diagnosis. METHODS: Forty-one cases of urothelial lesions exhibiting endophytic growth patterns were reviewed and reclassified as inverted papilloma, urothelial carcinoma with an endophytic growth pattern, and florid von Brunn nest. The gains of chromosomes 3, 7, and 17 and loss of 9p21 was detected by FISH, and performed immunohistochemical staining for CK20, p53, and Ki-67. Follow-up data of 12 cases were obtained. RESULTS: (1) Twelve inverted papillomas sized 1.2 cm in average, consisted of anastomosing cords and nests with uniform width distribution involving the lamina propria, the central portion contained streaming cells with squamous metaplasia, and the periphery showed palisading. No or rare atypia and mitosis were found. Focal exophytic papillary component lined by less than 6 layers of normal urothelium were observed in 4 cases. (2) Twenty-four urothelial carcinomas with an endophytic growth pattern sized 2.1 cm in average, demonstrated the similar architecture with inverted papilloma, but exhibited thick columns and variable thickness of the cords, irregular size and shape of large nests with transition into solids. Mild to moderate cytologic atypia was shown, and mitotic figures ranged 1 to 8 per 10 HPFs. Exophytic papillary component was not observed in 3 cases, but the superficial urothelium showed dysplasia, while coexisted exophytic component in other cases was associated with low malignant potential or low grade tumor. (3) Five florid von Brunn nests sized 0.9 cm in average, had normal or hyperplastic urothelium, variable nests with cysts compacted in lamina propria, no cytologic atypia and mitosis. Twenty-one of 24 (79.1%) urothelial carcinomas with an endophytic growth pattern displayed abnormally positive results by multitargeted FISH, whereas all inverted papillomas and florid von Brunn nests were negative. Immunohistochemically, CK20 was weakly positive in 2 cases of urothelial carcinoma with an endophytic growth pattern, and negative in all inverted papillomas and florid von Brunn nests. p53 weakly stained 5% to 50% nuclei of the tumor cells in 16 cases of urothelial carcinomas with an endophytic growth pattern and 1 inverted papilloma. 1%-5% tumor cells expressed Ki-67 in urothelial carcinoma with an endophytic growth pattern, and less than 1% in inverted papilloma and florid von Brunn nests. Follow-up study revealed that 2 cases of urothelial carcinoma with an endophytic growth pattern had developed invasive carcinoma, underwent cystectomy, and metastasized remotely. No recurrence occurred in cases of inverted papilloma. CONCLUSIONS: Benign and malignant urothelial lesions with an endophytic growth pattern present histologic overlapping. Urothelial carcinoma with an endophytic growth pattern displays unique characteristics in morphology and immunohistochemistry. Multitargeted FISH analysis is helpful in the differential diagnosis.

The clinicopathological relevance of uniform CD56 expression in anaplastic large cell lymphoma: a retrospective analysis of 18 cases.

BACKGROUND: Anaplastic large cell lymphoma (ALCL) with uniform CD56 expression is a rare condition, that has been described in limited literature, and its clinicopathological features have not yet been well illustrated. The aim of our study was to fully investigate the clinical, histological, immunohistochemical and molecular features of CD56+ ALCL. METHODS: The clinical and histological characteristics of CD56+ ALCL cases were retrospectively evaluated. The immunohistochemical phenotype, status of Epstein-Barr virus (EBV) and T-cell receptor (TCR) gene rearrangement were examined. Overall survival was also analyzed. RESULTS: Eighteen (5.8%) cases with diffuse CD56 expression were identified out of 313 archived ALCL cases with CD56 test. CD56 expression was significantly higher in ALK+ systemic ALCLs (sALCLs) (13/64, 20.3%) than in ALK- sALCLs (3/101, 3.0%) (p < 0.001) as well as primary cutaneous ALCLs (2/148, 1.4%) (p < 0.001). Regarding the CD56+ ALK+ sALCLs, the median age was 20 years (range, 8-60 years) with a male-to-female ratio of 2.3:1, and these cases more frequently affected extranodal sites (11/38, 28.9%) rather than lymph nodes (2/26, 7.7%) (p = 0.038). Eleven (84.6%) cases presented with stage I-II diseases, which was significantly more than their CD56- ALK+ counterparts (45.5%) (p = 0.015). Histologically, 2 ALK+ cases were of small cell variant and all the others displayed characteristic morphology of classic ALCL. Regarding the immunophenotype, both CD30 and CD56 were diffusely positive in all cases. CD3, CD43, anaplastic lymphoma kinase-1 (ALK1), TIA-1, EMA expression was observed in 30.8% (4/13), 90.9% (10/11), 100% (13/13), 100% (9/9), and 80.0% (8/10) cases, respectively. EBV infection was consistently absent. Monoclonal TCR gene rearrangement was found in 100% (5/5) of investigated ALK+ cases. Chemotherapy with a CHOP regimen was most frequently employed. The 3-year overall survival (OS) rate for CD56+ ALK+ patients was 92.0%, compared with 73.0% for their CD56- counterparts, but there was no significant difference in OS between the two groups (p = 0.264). CONCLUSIONS: Uniform CD56 expression is an unexpected condition in ALCL. Of ALK+ ALCLs, CD56 expression correlated with a high frequency of early stage and an extranodal predominance. It is of great importance to raise awareness of this condition and familiarity with its characteristic features to avoid diagnostic and therapeutic pitfalls. Further investigations are warranted for a better understanding of this unusual phenotype and the significance of CD56 expression in ALCL.

[Low-grade central osteosarcoma: a clinicopathologic analysis of nine cases].

OBJECTIVE: to study the clinicopathologic features and differential diagnosis of low-grade central osteosarcoma (LGCOS). METHODS: nine cases of LGCOS were retrieved from the archival consultation files. The clinical, radiologic and pathologic features were analyzed, with literature review. RESULTS: the mean age of the patients was 31 years. The male-to-female ratio was 3:6. All of the patients presented with painful mass and/or swelling. The sites of involvement included thigh (n = 4), tibia (n = 1), fibula (n = 1), cervical vertebra (n = 1), lumbar vertebra (n = 1) and maxilla (n = 1). Radiologic examination showed mixed lytic/blastic lesions with soft tissue shadow in 5 cases and associated periosteal reaction in 3 cases. The tumors were treated by surgical excision, with no adjuvant therapy given. The duration of follow up ranged from 2 to 43 months. Four cases had recurrence which occurred at 8 to 25 months after the operation. Gross examination showed that the tumors were fragmented on submission in 5 cases and en bloc in 4 cases. They had solid and firm cut surface, with various degree of grittiness. Histologically, LGCOS was characterized by the presence of hypocellular fibroblastic stroma associated with focal osteoid production. The spindly tumor cells showed mild degree of nuclear pleomorphism, with occasional mitotic figures demonstrated in all of the 9 cases. The newly formed neoplastic woven bone did not have any osteoblastic rimming. The bony trabeculae were slender and seam-like. Parallel arrays of woven bone were seen in 6 cases. Some of the bony trabeculae appeared irregularly branched and curved. The tumor cells permeated adjoining pre-existing bony trabeculae and bone marrow in all cases. Three cases also showed soft tissue involvement. CONCLUSIONS: LGCOS often posses important diagnostic pitfalls due to the relatively bland-looking tumor cell morphology and associated large woven or longitudinal seams of lamellar-like bone. Thorough understanding of the histologic features, when coupled with clinical and radiologic findings, are essential in arriving at a correct diagnosis.

[Angiomatoid fibrous histiocytoma: report of 5 cases with review of literature].

OBJECTIVE: To study the clinicopathologic features, immunophenotype and differential diagnosis of angiomatoid fibrous histiocytoma (AFH). METHODS: The clinicopathologic features of 5 cases of AFH were analyzed. Immunohistochemical study was carried out and the literature was reviewed. RESULTS: There were a total of 3 males and 2 females. The average age of patients was 21.4 years old. The average duration of symptoms was 13 months. The patients primarily presented with a slowly enlarging painless deep dermal or subcutaneous mass. The mass was located in the head and neck region in 3 cases, elbow in 1 case and foot in 1 case. The patients underwent complete resection of the tumor, with no adjuvant chemotherapy and/or radiotherapy given. During a period of follow up for 10 to 29 months, all of them had no recurrence or distant metastasis. Gross examination showed that the tumor was well-circumscribed and had a grey-colored cut surface, with focal hemorrhagic cystic changes. The average tumor dimension was 1.9 cm. Histologically, the tumor was composed of histiocytoid or spindly cells arranged in nodular pattern. Fibrillary neuropil-type intercellular material was identified in all cases and a fibrous pseudocapsule surrounded by lymphocytes and plasma cells was demonstrated in 3 cases. Immunohistochemical study showed that all of them were positive for vimentin and negative for S-100 protein, pan-cytokeratin, CD34 and CD31. Three of the cases expressed desmin and CD68. Two cases were epithelial membrane antigen and CD99-positive. CONCLUSIONS: AFH is a rare tumor of intermediate malignant potential. Definitive diagnosis requires thorough histologic examination and clinical correlation. Immunohistochemistry is also helpful for diagnosis and differential diagnosis. Wide local excision with post-operative follow up is the main modality of treatment.

[Prevalence of germinal center B-cell-like and non-germinal center B-cell-like types of diffuse large B-cell lymphoma in Shanghai, China].

OBJECTIVE: To study the prevalence of germinal center B-cell-like (GCB) and non-GCB-like types of diffuse large B-cell lymphoma (DLBCL) in Chinese patients. METHODS: Immunohistochemical study for CD10, bcl-6, MUM1, GCET1 and FOXP1 was performed on 124 cases of DLBCL from Shanghai, China. The Hans algorithm and Choi algorithm were applied to classify DLBCL into GCB and non-GCB-like types. Fluorescence in-situ hybridization (FISH) for t (14;18) and bcl-6 gene rearrangement was also carried out on 118 cases. RESULTS: Of the 124 DLBCL cases studied, 27 cases (22%) showed a GCB-like type and 97 cases (78%) showed a non-GCB-like type, when using Hans algorithm. On the other hand, 34 cases (27%) belonged to GCB-like type and 90 cases (73%) belonged to non-GCB-like type when applying Choi algorithm. The prevalence of GCB-like type was significantly lower than that of non-GCB-like type (P=0.0001). Only four cases (3%) were positive for t (14;18), and three of them were classified as GCB-like type. bcl-6 rearrangement was found in 46 cases (39%) and more frequently encountered in the GCB-like type. There is no relationship between bcl-6 gene rearrangement and bcl-6 protein expression. CONCLUSIONS: The GCB-like type of DLBCL is significantly less common than non-GCB-like type in Chinese population. This phenomenon is possibly related to the low frequency of t (14;18).

[Clinicopathologic study of giant cell angioblastoma].

OBJECTIVE: to study the clinicopathological features, imaging characteristics, immunophenotypes and differential diagnosis of giant cell angioblastoma (GCAB). METHODS: a case of GCAB in the left middle-upper tibia and fibula was studied by light microscopy, X-ray and CT imaging, immunohistochemistry. RESULTS: X-ray and CT imaging showed a clearer lesion in the left middle-upper tibia than in the ipsilateral fibula with enlarged ostealleosis and increased inhomogeneously medullary cavity density, irregular thickening of cortical bone, local cortical default at the inner edge, soft tissue swelling around the abnormal bone. Histologically, tumor tissue was located between the bone trabeculae by nodular, linear and plexiform aggregates of oval-to-spindle cells, large mononucleate cells and multinucleate giant cells with prominent nucleoli and abundant granular eosinophilic cytoplasm. Some aggregates had uncentain amount of discernible lumens, either empty or containing few erythrocytes. A concentric arrangement of oval-to-spindle Cells around small-caliber vascular structures together with collagen fiber contributed to a so-called 'onion-skin' arrangement. The background showed a loose mesenchymal stroma formed of some inconspicuous spindle-fibroblast-like cells, stellate-shape mesenchymal cells, a moderate mononuclear inflammatory cell infiltrate and scattered mast cells. Immunophenotype showed the tumor cells and giant cells strongly positive for vimentin. A good many oval-to-spindle cells stained markedly for CD31 and CD34, but weakly for FVIII, while the giant cells are highlighted instead by CD68, occasionally, very few giant cells showed positive focally for FVIII, a-SMA decorated notedly the cells surrounding the endothelium-like cells but weakly positive in some other tumor cells. CONCLUSION: GCAB is a rare, locally infiltrative but slow growing neoplastic angiogenesis with unique morphological characteristics during infancy, which may occur not only in the skin, mucosa, subcutis and deep soft tissue but also in the bone.

[Immunoglobulin heavy chain gene rearrangement study in difficult cases of B-cell lymphoproliferative disorder].

OBJECTIVE: To evaluate the ancillary diagnostic value of IgH gene rearrangements in those B-cell lymphoproliferative disorder cases whom are difficult in making a final diagnosis. METHODS: IgH gene clonal rearrangements were retrospectively analyzed in a total of 77 diagnostically difficult B-cell lympho-proliferative patients. Standardized BIOMED-2 system IgH gene clonality assay kit targeting FR1, FR2, FR3 was used, followed by heteroduplex-polyacrylamide gel electrophoresis (PAGE) and silver nitrate staining. RESULTS: The final diagnoses of the 77 cases were: 12 cases of reactive lymphoid hyperplasia, 20 cases of atypical lymphoid hyperplasia or suspicious lymphoma, and 45 cases of B-cell lymphoma. Detection rates of at least one positive reaction were 2/12, 11/20 (55%), 36/45 (80%) in the three groups, respectively. In B-cell lymphomas, the clonality detection rate of FR1, FR2 and FR3 was 60% (27/45), 60% (27/45) and 56% (25/45), respectively. The type distribution were: 20 marginal zone lymphomas, including 18 extranodal marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue, 7 diffuse large B-cell lymphomas, 7 follicular lymphomas, 1 mantle-cell lymphoma, 1 Burkitt's lymphoma, 4 plasma cell neoplasms and 5 unclassified B-cell lymphomas. Rearrangements of FR1, FR2 or FR3 were not detected in 9 (20%) of the B cell lymphoma cases, nevertheless, one of them had developed liver lesion later, and was confirmed finally to be B cell lymphoma. Fourteen patients of reactive lymphoid hyperplasia with positive IgH gene clonal rearrangements, and atypical lymphoid hyperplasia had follow-up history available. Four of them were diagnosed as lymphoid malignancies upon further biopsy, and in three of them, clonal IgH gene rearrangements were detected. CONCLUSIONS: B-cell lymphoproliferative disorder requiring a detection of clonal IgH gene rearrangement for making a final diagnosis. Combined detections of three IgH FR1, FR2 and FR3 rearrangements provide important ancillary diagnostic value in confirming suspected B-cell lympho-proliferative disorders. It is important to take an additional biopsy or to follow-up those patients who that have a detectable IgH gene clonal rearrangement but without apparent morphological evidence of lymphoma. For cases with a negative IgH gene rearrangements, it might be necessary to perform clonality analysis for other forms of gene rearrangements including IgH or IgK and IgL in order to further improve the detection sensitivity.

[Study on clinicopathologic parameters of malignant behavior in gastrointestinal stromal tumors].

OBJECTIVE: To determinate the clinicopathologic parameters in predicting the malignant behavior of gastrointestinal stromal tumor (GIST). METHODS: Eight hundred and forty cases of GIST were retrospectively reviewed. The tumors were classified as malignant if they met any of the following criteria: evidence of gross dissemination (including liver metastasis and/or peritoneal spread), evidence of microscopic dissemination (including lymph node metastasis, infiltration to vessels, fat tissue, nerves and/or mucosal tissue), or disease relapse. The remaining cases were provisionally classified as tumors of uncertain biologic behavior. A number of morphologic parameters were then evaluated under light microscopy and univariate and multivariate analyses were adopted for this study. RESULTS: Histologic findings correlated with evidences of the following morphologic parameters were considered in accord with the criteria of the malignant behavior: mitotic count>or=10 per 50 high-power fields (P<0.01), muscle infiltration (P<0.01), coagulative necrosis (P<0.01), perivascular growth pattern (P=0.005) and remarkable nuclear atypia (P=0.014). Basing on the above criterion, 485 cases were re-classified as "malignant" and 355 cases "non-malignant". Follow-up data showed that the five-year disease-free survival and overall survival in the "non-malignant" group were 99.3% and 100% respectively, in contrast to 43.9% and 59.7% respectively in the "malignant" group (P<0.01). CONCLUSIONS: The set of clinicopathologic parameters is useful in predicting the malignant behavior of GIST and prognosis.

Stage and histological grade of gastrointestinal stromal tumors based on a new approach are strongly associated with clinical behaviors.

Tumor stage and grade for gastrointestinal stromal tumors are poorly defined. To develop a better evaluation system, we assessed 12 clinical and pathological parameters in 613 patients with follow-up information. These parameters were classified into two gross spread parameters including liver metastasis and peritoneal dissemination, five microscopic spread parameters including lymph node metastasis, vascular, fat, nerve and mucosal infiltration, and five histological parameters including mitotic count > or =10 per 50 high-power fields, muscularis propria infiltration, coagulative necrosis, perivascular pattern and severe nuclear atypia. The 5-year disease-free survival and overall survival of 293 patients without any of these predictive parameters of malignancy were 99 and 100%, respectively. They were regarded as nonmalignant and further evaluations on the stage and grade of these tumors were not performed. At least one and at most seven predictive parameters of malignancy were identified in 320 patients. For these patients, the 5-year disease-free survival and overall survival rates were 44% (mean 6.7 years) and 60% (mean 9.3 years), respectively. The disease-free survival showed significant difference between patients with and without gross spread (P<0.0001), with and without microscopic spread (P=0.0009). Disease-free survival and overall survival were associated with the number of predictive parameters of malignancy in patients without gross spread (P<0.0001 for both disease-free survival and overall survival), but not in patients with gross spread (P=0.882 and 0.441, respectively). Malignant gastrointestinal stromal tumors could be divided into clinical stage I and II based on the absence and presence of gross spread, respectively. The degree of malignancy of patients in clinical stage I could be graded according to the number of predictive parameters of malignancy. Patients in clinical stage II were of the highest degree of malignancy regardless of the number of parameters. We found that the clinical stage and grade were strongly associated with prognosis.

[Immunohistochemical study using T-cell lymphoma antibody 1 and CD44 in diagnosis of Burkitt's lymphoma].

OBJECTIVE: To study the values of immunohistochemistry using T-cell lymphoma antibody (TCL) 1 and CD44 in the diagnosis of Burkitt's lymphoma. METHODS: Immunohistochemical study for TCL1, CD44, CD10, bcl-2, bcl-6, c-myc and Ki-67 was performed on paraffin-embedded sections of lymphoma cases, including 25 cases of Burkitt's lymphoma and 25 cases of diffuse large B-cell lymphoma. RESULTS: Burkitt's lymphoma commonly expressed TCL1 (96%, 24 cases), CD10 (88%, 22 cases), bcl-6 and c-myc (92%, 23 cases). Only 1 case (4%) expressed CD44 and bcl-2. The Ki-67 proliferation index ranged from 95% to 100%. On the other hand, diffuse large B-cell lymphoma expressed CD44 (84%, 21 cases), CD10 (32%, 8 cases), bcl-6 (72%, 18 cases) and bcl-2 (72%, 18 cases). Four cases (16%) were weakly positive for TCL1. The staining for c-myc was all negative. The Ki-67 proliferation index ranged from 40% to 90%. CONCLUSION: Immunohistochemical staining for TCL1 and CD44 is a useful ancillary tool in the pathologic diagnosis of Burkitt's lymphoma which is also helpful for the differential diagnosis from diffuse large B-cell lymphoma.

[Clinicopathologic analysis of mixed epithelial and stromal tumor of kidney and adult cystic nephroma].

OBJECTIVE: To study the clinicopathologic features, immunophenotype and differential diagnosis of mixed epithelial and stromal tumor of kidney (MEST) and adult cystic nephroma (CN). METHODS: Five cases of MEST and 4 cases of CN were retrospectively analyzed. Immunohistochemical study was carried out and the literature was reviewed. RESULTS: All of the five patients with MEST were females. Their median age was 45 years. For CN, there were 3 males and 1 female and their median age was 41 years. All patients presented with loin pain and hematuria. On gross examination, MEST was well-circumscribed but non-encapsulated. There was no evidence of haemorrhage or necrosis. Three of the cases were solid in nature. One was composed of a mixture of solid and cystic elements, while the remaining case showed a multicystic cut surface bridged by thick fibrous septa. On the other hand, CN were well-circumscribed and encapsulated. They were multiloculated cystic in nature. The cystic spaces were separated by thin septa and there was no significant solid or necrotic component. Histologically, MEST consisted of proliferation of cystically dilated glands admixed with spindly stromal cells with various cellularity and growth patterns. Both the glandular and stromal elements were well-differentiated with no cytologic atypia identified. The glandular structures in 2 of the cases were partially lined by endometrial or tubal epithelium. In contrast, the thin-walled cystic spaces in CN were lined by a single layer of epithelium.Immunohistochemical study showed that the epithelial cells were positive for pan-cytokeratin and epithelial membrane antigen. The spindle cells in MEST expressed vimentin (5/5), smooth muscle actin (3/5), desmin (4/5), CD10 (5/5), estrogen receptor (4/5) and progesterone receptor (4/5). They were negative for HMB45, CD34, CD117 and S-100 protein. On the other hand, the spindle cells in CN were variably positive for vimentin (4/4), smooth muscle actin (4/4), desmin (1/4), estrogen receptor (3/4) and progesterone receptor (1/4). They were negative for CD10, HMB45, CD34, CD117 and S-100 protein. CONCLUSIONS: Both MEST and CN are uncommon renal neoplasm. Most of them run a benign clinical course. The stromal cells in MEST show smooth muscle or myofibroblastic differentiation. Areas demonstrating Müllerian features also existed in some cases. MEST and CN share overlapping histological and immunohistochemical features, and may represent spectrum of the same group of lesions.

[Clinicopathologic analysis of pulmonary lymphangioleiomyomatosis].

OBJECTIVE: To improve the understanding and diagnosis of pulmonary lymphangioleiomyomatosis (LAM). METHODS: Fifteen cases of LAM of our hospital were presented and 73 cases reported in domestic literature from 1993 to 2008 were reviewed. By means of histological and immunohistochemical(IHC)studies, the clinical and pathological features of LAM were analyzed. RESULTS: All the 88 cases were female, with an average age of onset at (37 +/- 9) years. The main clinical manifestations included dyspnea (83/88, 94%), hemoptysis (48/88, 54%), pneumothorax (41/88, 47%), and chylothorax (28/88, 32%). High resolution computerized tomography (HRCT) showed thin-walled air-filled cysts throughout both lungs. Pathological features showed cystic changes in the lung, and abnormal smooth muscle cells (LAM cells) lined the airways, bronchioles, lymphatics and blood vessels leading to airflow obstruction and replacement of the lung parenchyma by cysts. In the autopsy case, extrapulmonary organs (eg, kidney, lymph nodes and soft tissues) were also involved. Abnormal manifestations in abdomen, including renal mass, retroperitoneal mass and retroperitoneal lymphadenopathy, were detected in 23 cases. CONCLUSIONS: LAM is a multisystem disease. Chest HRCT had confirmative value for diagnosis of LAM. In practice, chest HRCT, as well as other routine abdominal and pelvic imaging examinations, should be performed for child-bearing-age women with progressive dyspnea, hemoptysis, or spontaneous pneumothorax.