Mediastinal type B3 thymoma combined with germ cell tumor: cytologic diagnosis.

Primary mediastinal thymoma combined with germ cell tumor (GCT) is extremely rare, and is likely to be misdiagnosed. Here we report a case of mediastinal type B3 thymoma combined with seminoma in which the seminoma component was missed by histologic examination and initially diagnosed by using a pleural effusion sample. The patient was a 46 year old male with chest distress, cough, and supraclavicular lymph node enlargement. A large anterior mediastinal mass was revealed by diagnostic imaging. The tumor was completely removed by thoracotomy. Grossly, a solid mass about 10 cm × 8 cm × 5 cm with cystic degeneration was found. Histologic examination revealed Type B3 thymoma accompanying with multiple lymph node metastases. One year later, CT scan found an irregular mass on the right side of anterior-superior mediastinum with a large amount of effusion in the right side pleural cavity. Cytologic examination and immunostains of the pleural effusion sample revealed metastatic seminoma. Then the original surgical sample was reviewed and the seminoma component also was found besides the thymoma. To the best of our knowledge, this is the first description of type B3 thymoma combined with seminoma, diagnosed by histology and pleural effusion together. We also present a literature review.

Clinical and pathological characteristic of metastatic malignant mesothelioma initially diagnosed by lymph node biopsy.

BACKGROUND: It is a great challenge for pathologists to initially diagnose metastatic malignant mesothelioma (MM) by the lymph node biopsy without any history of primary MM. Because the onset of MM is hidden and the metastatic MM in lymph node is relatively uncommon. Besides, morphologic and immuohistochemistry features of MM are similar to other tumors. METHODS: In order to improve the initial diagnostic accuracy of metastatic MM from LN biopsy and to reduce or avoid the possibility of missed diagnosis or misdiagnosis, we had collected the clinical and pathological data of the metastatic MM cases in our department, and summarized the characteristics of morphological, immunohistochemical and fluorescence in situ hybridization (FISH) results. RESULTS: Seven patients (4 males and 3 females) with 21-73 year-old had been included in our study. Six cases showed serous cavity effusion, serosal thickening and systemic multiple lymph node enlargement. The "moderate, nice" tumor cells were arranged in variable patterns. Mitosis was hardly to be found and necrosis was absent. Four immunohistochemical staining panels and FISH detection had been used for diagnosis and differential diagnosis of MM. All cases expressed broad-spectrum epithelial markers and at least 2 mesothelial-cell-origin markers. None were positive for specific-tissue-origin markers, and all cases were diagnosed of malignancy according to immunohistochemical markers and detection of pl6 gene deletion. CONCLUSION: It is necessary for us to keep our awareness of metastatic MM in lymph node. Correct diagnosis of MM metastasis by lymph node biopsy were based on detailed understanding of the clinical manifestation and the image data, careful observation of morphologic characteristics, and properly using immunohistochemical markers or FISH detection if necessary for diagnosis and differential diagnosis.

Clinicopathologic Characterization of Aggressive Natural Killer Cell Leukemia Involving Different Tissue Sites.

Aggressive natural killer cell leukemia (ANKL) is a rare disease with an extremely aggressive clinical course. The etiology of ANKL is unclear with few genetic/epigenetic aberrations described to date. Moreover, misdiagnosis of ANKL is a frequent problem. Clinicopathologic characteristics of 35 retrospective cases of ANKL were investigated with the aim of improving diagnosis and to find the genetic/epigenetic aberrations associated with ANKL etiology. Because of the relatively low number of leukemic cells in the peripheral blood and bone marrow, diagnosis of ANKL can be missed; therefore, it is important to perform biopsy on solid tissues, if necessary. We describe the pathology of ANKL in the lymph nodes, bone marrow, spleen, liver, and skin, with focus on diagnosis and differentiated diagnosis. We observed young male predominance in our cohort, and the clinical course was more aggressive than reported previously. Low lactate dehydrogenase (<712 IU/L), chemotherapy or L-asparaginase administration were found to be associated with more favorable outcomes. SH2 domains of STAT5B and STAT3 also were screened for the presence of activating mutations. Moreover, CpG island methylation status of HACE1, a candidate tumor-suppressor gene, was determined in ANKL samples. We observed activating STAT5B mutations (1/5) and hypermethylation of HACE1 (3/4) in ANKL cases, suggesting that these aberrations may contribute to ANKL pathogenesis.

Clinical analysis of 1629 newly diagnosed malignant lymphomas in current residents of Sichuan province, China.

Previous studies in other provinces of China (Beijing, Xinjiang, Shanxi, Jiangxi, Shanghai, Guangdong, and Taiwan) suggest that the distributions of lymphoma subtypes differ compared with Western populations. In order to evaluate the characteristics of malignant lymphoma in Sichuan, China, we analyzed case series data from incident lymphoma patients diagnosed in 2008 from three hospitals, including a total of 1629 cases and including only current residents of Sichuan. The median age of diagnosis for cases was 54 years, with a higher proportion of male cases compared with female cases. The most commonly diagnosed subtypes included diffuse large B-cell lymphoma (40.4%), NK/T-cell lymphoma (NKTCL; 11.8%), mixed cellularity Hodgkin lymphoma (7.0%), mantle cell lymphoma (4.8%), and marginal zone B-cell lymphoma (3.9%). Differences in demographic characteristics between Hodgkin lymphoma (HL) and non-Hodgkin lymphoma (NHL) cases were apparent for median age at diagnosis (HL: 34 years; NHL: 57 years), and NHLs accounted for nearly all (99.3%) of the 931 cases of extranodal lymphoma. These findings indicate a higher proportion of NKTCL cases and a lower proportion of follicular lymphoma cases (2.3%) in these hospitals in Sichuan, relative to reports from some other provinces within China (e.g., Shanghai and Shanxi) and the USA. Copyright © 2015 John Wiley & Sons, Ltd.

Suppressive effects of microRNA-16 on the proliferation, invasion and metastasis of hepatocellular carcinoma cells.

miR-16 is known to be abnormally expressed in hepatocellular carcinoma (HCC) cells, and the overexpression of miR-16 inhibits the proliferation, invasion and metastasis of various cancer cells. MicroRNAs (miRNAs or miRs) are closely related to the proliferation, invasion and metastasis of HCC. The present study aimed to explore the effects of miR-16 on the proliferation, invasion and metastasis of HCC cells, and to elucidate the mechanisms involved. A cell line with moderate levels of miR­16 expression was selected from the SMMC-7721, HepG2, SK-Hep-1 and Huh­7 HCC cells and validated by reverse transcription-PCR (RT-PCR). The effects of miR­16 on HCC cell viability were determined by MTT assay; cell migration and invasion were determined by Transwell cell invasion assay, and apoptosis was determined by flow cytometery (FCM). Western blot analysis was used to measure the expression levels of the apoptosis-related proteins, Bax, Bcl-2, matrix metalloproteinase (MMP)-2, MMP-9, as well as to examine epithelial-mesenchymal transition (EMT), and E-cadherin, vimentin, and phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathway-related protein expression. The mRNA expression levels of miR­16 were highest in the SMMC-7721 cells and lowest in the SK-Hep­1 and Huh­7 cells; moderate levels were observed in the HepG2 cells. The HepG2 cell line was selected as the cell line for use in the follow-up experiments, where we measured cell viability, and the expression of PI3k/Akt, Bax, Bcl-2, MMP-2 and MMP-9, and E-cadherin and vimentin. miR­16 overexpression significantly inhibited the proliferation, invasion and metastasis of the HepG2 cells, as shown by western blot analysis. This was achieved through the upregulation of Bax expression, the downregulation of Bcl-2 expression and the decrease in the expression of MMP-2 and MMP-9. In addition the expression of E-cadherin increased and vimentin expression decreased. miR­16 overexpression inhibited PI3K expression and Akt phosphorylation. The results of this study suggest that the overexpression of miR­16 inhibits the proliferation, invasion and metastasis of HepG2 HCC cells, and that these effects are associated with the PI3K/Akt signaling pathway.

Immunohistochemical differentiation between type B3 thymomas and thymic squamous cell carcinomas.

Type B3 thymomas and thymic squamous cell carcinomas have some overlapping histological features, so it is difficult to make the differential diagnosis between these two entities, especially when the biopsy specimen is small. Only a few markers such as CD5 and CD 117 were applied to the differential diagnosis, the purpose of this study is to identify other diagnostic markers to help making the differential diagnosis more accurate. GLUT-1, MUC-1, CD117, CD5, CEA, P63, CK19, CK5/6, CD1a and TdT were evaluated using 16 cases of type B3 thymoma and 20 cases of thymic squamous cell carcinoma. Staining scores were obtained by calculating the percentage of positive cells. The sensitivity of GLUT-1 or MUC-1 for thymic squamous cell carcinomas was highest (100%), followed by CK5/6 (95%), CD117 (90%), P63 (85%), CD5 (80%) and CEA (75%). The specificities of CD5, CD117 and CEA for thymic squamous cell carcinomas all were 100%, next was MUC-1 (56.3%), followed by GLUT-1 (50%), P63 (25%), CK5/6 (12.5%). The sensitivities of CK19, TdT, and CD1a for type B3 thymomas were 100%, 93.8% and 87.5%, respectively. The specificity of CD1a for type B3 thymomas was highest (100%), followed by TdT (95%), CK19 (10%). The reactivity of GLUT-1, MUC-1, CD117, CD5, CEA, CD1a and TdT in thymic squamous cell carcinomas and type B3 thymomas had significant difference. Usually a panel of markers is needed, if we combine GLUT-1 or MUC-1 which sensitivity for thymic squamous cell carcinomas is highest with CD5, CD117, CEA, CD1a or TdT which have high specificity, we can make the differential diagnosis effectively.

Receptor-type tyrosine-protein phosphatase κ directly targets STAT3 activation for tumor suppression in nasal NK/T-cell lymphoma.

Nasal-type natural killer/T-cell lymphoma (NKTCL) is an aggressive disease characterized by frequent deletions on 6q, and constitutive activation of signal transducer and activator of transcription 3 (STAT3). Phosphorylation at Tyr705 activates STAT3, inducing dimerization, nuclear translocation, and DNA binding. In this study, we investigated whether receptor-type tyrosine-protein phosphatase κ (PTPRK), the only protein tyrosine phosphatase at 6q that contains a STAT3-specifying motif, negatively regulates STAT3 activation in NKTCL. PTPRK was highly expressed in normal NK cells but was underexpressed in 4 of 5 (80%) NKTCL cell lines and 15 of 27 (55.6%) primary tumors. Significantly, PTPRK protein expression was inversely correlated with nuclear phospho-STAT3(Tyr705) expression in NKTCL cell lines (P = .025) and tumors (P = .040). PTPRK restoration decreased nuclear phospho-STAT3(Tyr705) levels, whereas knockdown of PTPRK increased such levels in NKTCL cells. Phosphatase substrate-trapping mutant assays demonstrated the binding of PTPRK to STAT3, and phosphatase assays showed that PTPRK directly dephosphorylated phospho-STAT3(Tyr705). Restoration of PTPRK inhibited tumor cell growth and reduced the migration and invasion ability of NKTCL cells. Monoallelic deletion and promoter hypermethylation caused underexpression of PTPRK messenger RNA in NKTCL, and methylation of the PTPRK promoter significantly correlated with inferior overall survival (P = .049) in NKTCL patients treated with the steroid-dexamethasone, methotrexate, ifosfamide, l-asparaginase, and etoposide regimen. Altogether, our findings show that PTPRK underexpression leads to STAT3 activation and contributes to NKTCL pathogenesis.

ACTH-secreting pancreatic neuroendocrine carcinoma with ovarian and pelvic metastases causing Cushing's syndrome: a case report.

Adrenocorticotropin hormone (ACTH)-secreting pancreatic neuroendocrine carcinoma (NEC) with ovarian and pelvic metastases causing Cushing's syndrome is very rare and might be misdiagnosed. We describe a case of ACTH-secreting pancreatic poorly differentiated NEC developing bilateral ovarian and pelvic metastases. A 27-year-old woman presented with thirst, polydipsia, fatigue and poorly controlled hyperglycemia. Laboratory and imaging investigations revealed hypokalemia, hyperglycaemia, ACTH-dependent hypercortisolemia and a 12-cm mass at the junction of body and tail of the pancreas with ovarian and pelvic nodules. The patient underwent partial pancreatectomy and splenectomy, uterectomy, bilateral oophorectomy, and excision of peritoneal nodules. Tumors in pancreas, ovaries and pelvis were diagnosed as poor-differentiated NEC. After 19-month chemotherapy, she developed pelvic metastasis. The tumor in our case is a large, poorly differentiated NEC secreting ACTH and causing CS, with ovarian metastases. To our knowledge, this new additional case of ACTH-secreting pancreatic NEC with ovarian metastases would add to the better understanding of this tumor.

HIV-related Burkitt lymphoma with florid granulomatous reaction: an unusual case with good outcome.

Burkitt lymphoma (BL) is a highly aggressive subtype of non-Hodgkin lymphomas (NHL). Lymphoma related granulomatous reaction rarely occurs in sporadic BL. Herein, we describe the first case of HIV related Burkitt lymphoma with florid granulomatous reaction. A 41-year-old HIV-positive Chinese male presented lymphadenopathy in the right cervical region for 3 months. The enlarged lymph node biopsies revealed the presence of prominent granulomas of varying size with Langhans giant cells, leading to the misdiagnosis of tuberculous lymphadenitis in other hospital. Subsequently, the case was sent to us for consultation. The morphology, immunophenotype, special staining, interphase FISH analysis and blood tests confirmed a diagnosis of HIV related Burkitt lymphoma with granulomatous reaction. Without radiotherapy and chemotherapy, the patient was alive and well with no evidence of lymphoma during the observation period of 24 months. The case suggested that lymphoma with florid granulomatous reaction can easily be misdiagnosed as benign lesions since the large number of epithelioid granulomas could obscure the primary lesion. Moreover, the granulomatous reaction may be an indicator for favorable prognosis in HIV related Burkitt lymphoma.

[A clinicopathologic and prognosis study of Epstein-Barr virus positive diffuse large B-cell lymphoma in west-southern China].

OBJECTIVE: To investigate the clinicopathologic features, immunophenotype, and the prognosis related factors of Epstein-Barr virus (EBV) positive diffuse large B-cell lymphoma (DLBCL) in west-southern China. METHODS: There were 42 cases of EBV+ DLBCL in a total 586 DLBCL, the clinical and pathologic profiles of these patients were evaluated. Immunohistochemical study and in situ hybridization (ISH) of EBER1/2 were performed on formalin fixed tissues by tissue chips. The prognosis related factors were analyzed. RESULTS: The median age of these 42 EBV+ DLBCL patients was 62.5 years. The male-to-female ratio was 2.23 : 1. The site of occurrence included lymph node (69.05%) and spleen, stomach, tonsil, nasal cavity and nasopharynx. The mostly common initial clinical presentations were non-specific symptoms, such as lymphadenopathy, splenomegaly, hepatomegaly, fever, and fatigue. Morphologically, the majority (90.48%, 38/42) were pleomorphic subtypes and only 4 cases (9.52%) were simplex subtypes. Immunophenotype showed non-GCB type of DLBCL was predominance (83.33%, 35/42) by Hans classification. The expression of CD30, CD5, BCL-2, P53 and NF-kappaB/ P65 were 52.38% (22/42), 54.76% (23/42), 54.76% (23/42), 87.5% (35/40) and 0% (0/40) respectively. Follow-up data was available in 23 (54.76%) patients, 14 (60.87%) patients died of the tumor. 5-years overall survival was 16.5%. The median survival time was 40 months. The expression of BCL-2, increased LDH level and starry-sky morphologic character were associated with a poor prognosis. CONCLUSION: EBV positive DLBCL is not uncommon. Most lesions locate in lymph nodes. Pleomorphic histologic subtype is predominant. The tumor has worse prognosis with increased LDH level, starry-sky morphologic character and BCL-2 expression.

Immunohistochemical screening and fluorescence in situ hybridization confirmation of ALK translocation in lung adenocarcinoma and its clinicopathological significance: a single-center large-scale investigation of Chinese patients.

Anaplastic lymphoma kinase (ALK) translocation-positive adenocarcinoma of the lung is a newly recognized molecular subgroup. Limited data on the clinicopathological features of this entity in the Chinese population are available. We performed immunohistochemical staining for the ALK protein and fluorescence in situ hybridization detection of the ALK translocation. We enrolled 793 Chinese patients with lung adenocarcinoma and identified 54 ALK translocation-positive patients (6.8%) in the group. Compared with the entire group of patients, ALK translocation-positive patients were younger (P < .01) and more likely to be nonsmokers (P = .017), but presented with a higher percentage of advanced-stage disease (P = .022) and lymph node metastases (P = .006). ALK translocation-positive patients more commonly exhibited poorly differentiated tumor histology and a predominantly solid tumor growth pattern relative to the ALK translocation-negative patients. Morphologically, ALK translocation was associated with extracellular mucus secretion, a mucinous cribriform structure, and signet ring cell (SRC) components. ALK translocation was present in 42.5% and 34.0% of adenocarcinomas with SRC components or wild-type EGFR, respectively. ALK translocation, occurring at a frequency of 6.8% in Chinese patients, defines a unique molecular subgroup of lung tumors. Fluorescence in situ hybridization should be performed in each case of lung adenocarcinoma with SRC components or wild-type EGFR to identify ALK translocation-positive patients.

Thymic epithelial tumors: a clinicopathologic study of 249 cases from a single institution.

The WHO histological classification for thymic epithelial tumors of 2004 edition is widely used, but its prognostic value is still controversial. In the present study we collected 249 Chinese patients with thymic epithelial tumors from West China Hospital of Sichuan University since 1999-2009 to assess the prognosis relating to tumor stages, histological classifications, MG and adjuvant therapy. There were 18 cases of type A (7.2%), 97 of type AB (39.0%), 22 of type B1 (8.8%), 63 of type B2 (25.3%), 16 of type B3 (6.5%) thymomas and 33 of thymic carcinomas (13.3%). According to the Massaoka staging, there were 107 patients in stage I (43%), 73 patients in stage II (29.3%), 50 patients in stage III (20.1%) and 19 in stage IV (7.6%). 101 patients (40.6%) complicated with MG, the incidence of MG was highest in type B3 thymomas, then in B2, none of thymic carcinomas complicated with MG. Cox regression analysis showed the Masaoka stage was the most important prognostic factor. Besides of staging, WHO histological classification was also an independent prognostic factor. The age, gender, MG and adjuvant therapy have no significant influence to the prognosis of the patients.

Clinicopathology, immunophenotype, T cell receptor gene rearrangement, Epstein-Barr virus status and p53 gene mutation of cutaneous extranodal NK/T-cell lymphoma, nasal-type.

BACKGROUND: Extranodal natural killer/T-cell (NK/T cell) lymphoma, nasal-type, is a rare lymphoma. Skin is the second most common site of involvement after the nasal cavity/nasalpharynx. The aim of this study was to investigate the clinicopathologic features, immunophenotype, T cell receptor (TCR) gene rearrangement, the association with Epstein-Barr virus (EBV) infection and p53 gene mutations of the lymphoma. METHODS: The clinicopathologic analysis, immunohistochemistry, in situ hybridization for EBER1/2, TCR gene rearrangement by polymerase chain reaction (PCR), mutations of p53 gene analyzed by PCR and sequence analysis were employed in this study. RESULTS: In the 19 cases, the tumor primarily involved the dermis and subcutaneous layer. Immunohistochemical staining showed that most of the cases expressed CD45RO, CD56, CD3ε, TIA-1 and GrB. Three cases were positive for CD3 and two cases were positive for CD30. Monoclonal TCRγ gene rearrangement was found in 7 of 18 cases. The positive rate of EBER1/2 was 100%. No p53 gene mutation was detected on the exon 4 - 9 in the 18 cases. Fifteen cases showed Pro (proline)/Arg (arginine) single nucleotide polymorphisms (SNPs) on the exon 4 at codon 72. The expression of p53 protein was 72% (13/18) immunohistochemically. CONCLUSIONS: Cutaneous NK/T-cell lymphoma is a rare but highly aggressive lymphoma with poor prognosis. No p53 gene mutation was detected on the exon 4 - 9, and Pro/Arg SNPs on p53 codon 72 were detected in the cutaneous NK/T-cell lymphoma. The overexpression of p53 protein may not be the result of p53 gene mutation.

Expression of FOXP1 in mucosa-associated lymphoid tissue lymphoma suggests a large tumor cell transformation and predicts a poorer prognosis in the positive thyroid patients.

The forkhead box protein P1 (FOXP1) expression resulted from chromosome translocation was found in MALT lymphoma, and its nuclear expression in diffuse large B cell lymphoma has been believed to be a poor prognostic factor. In our study, FOXP1 expression was investigated in its relationship to the occurrence of large tumor cells, clinical features, and prognosis in a series of 115 MALT lymphomas divided into two groups with or without the large tumor cells. All cases were morphologically reviewed, and FOXP1 expression was detected both in mRNA and protein levels by real-time PCR, immunochemical staining, and Western blot hybridization. All available clinical data were collected. In the MALT lymphoma with large cells, FOXP1 expression was higher at both mRNA (P = 0.008) and protein (P = 0.000) levels than that in group without large cells, and most large tumor cells showed FOXP1 positivity. It was also found that cases beyond Ann Arbor stage I have a higher FOXP1 expression rate than cases in stage I (P = 0.01), moreover, FOXP1-positive group has more plasmacytic differentiation (P = 0.025), deeper filtrating depth in digestive tract (P = 0.039), and a higher Ki67 proliferation index (P = 0.022). However, no statistical significance was identified in the involved anatomic sites and prognosis. Our data demonstrated the close relationship between FOXP1 nuclear expression and the occurrence of large tumor cells in MALT lymphoma, which suggested the possibility of large cell transformation of FOXP1-positive cases. And FOXP1 positivity was associated with enhanced invasion and proliferation ability of tumor cells. In the thyroid cases, the FOXP1 positivity showed a poorer prognosis (P = 0.043), but the significance was not found in the overall survival analysis (P = 0.1123).

Sporadic Burkitt lymphomas of children and adolescents in Chinese: a clinicopathological study of 43 cases.

BACKGROUND: To investigate the clinical and pathologic features as well as the MYC translocations of childhood Burkitt lymphoma (BL) from China. METHODS: Fourty-three cases of childhood BL were retrospectively investigated in morphology, immunophenotype, genotype, treatments and survival analysis. RESULTS: Clinically, there was a marked male predominance in sex distribution (M: F=9.75:1); abdomen was the most frequent extranodal sites of involvement (46.5%), followed by jaws and facial bones (16.3%). Two third of the patients were in stageI ~ II. Morphologically, 69.76% of the cases showed classical histologic features, while 30.24% of them showed greater nuclear pleomorphism in size and shape. Five cases (11.6%) were positive for EBER1/2. Thirty-one of the 40 cases (77.5%) had the aberration of IGH/MYC translocation while 7 (17.5%) had non-IGH/MYC translocation. Thirty patients (69.7%) received operation and/or chemotherapy while 13 patients (30.3%) received no treatment. Twenty-seven patients (62.8%) died of the tumor, 16 alive, with the average survival time 4.9 and 48.7 months respectively. High IPI, advanced clinical stage, increased serum level of LDH and no chemotherapy received as well as tumor size≥10 cm were related to the lower survival rates of the tumor. CONCLUSIONS: Several differences were showed in this group of BL, including a much higher ratio of male patients, more cases in stageII, clinically inconsistent treatment and a very poor outcome. VIRTUAL SLIDES: The virtual slide(s) for this article can be found here http://www.diagnosticpathology.diagnomx.eu/vs/1552295877710135.

[Detection of epidermal growth factor receptor gene mutation in non-small cell lung cancer by allele-specific oligonucleotide-PCR and bi-loop probe specific primer quantitative PCR].

OBJECTIVE: To compare the detection sensitivity of epidermal growth factor receptor (EGFR) mutations between allele specific oligonucleotide PCR (ASO-PCR) and bi-loop probe and specific primer quantitative PCR (BPSP-qPCR). METHODS: A total of 96 non-small cell lung cancer specimens were selected from West China Hospital from September 2009 to December 2010. ASO-PCR was developed to detect the presence of classical EGFR mutations. A total 39 available specimens were also tested by BPSP-qPCR. RESULTS: EGFR mutation detection rate was 30.2% (26/96) by ASO-PCR. The mutation rate was higher in female than in male patients [45.5% (20/44) vs. 17.3% (9/52), P = 0.003], non-smokers than smokers [44.1% (26/59) vs. 8.1% (3/37), P < 0.001] and adenocarcinomas than other subtypes of lung cancer [37.0% (27/73) vs. 8.7% (2/23), P = 0.01]. Among mutation negative cases by ASO-PCR, BPSP-qPCR increased the rate of detection of 19-del and L858R mutation by 10.3% (4/39) in adenocarcinomas and non-smoking subset. Overall, the mutation detection rate of BPSP-qPCR was higher than that of ASO-PCR [66.7% (26/39) vs. 41.0% (16/39), P = 0.02]. CONCLUSION: BPSP-qPCR has a better detection sensitivity than that of ASO-PCR.

In situ follicular lymphoma with progressive transformation of the germinal centers confirmed by laser capture microdissection, IGH gene rearrangement analysis, and fluorescence in situ hybridization for t(14;18).

The authors report an unusual case of in situ follicular lymphoma associated with progressive transformation of the germinal centers. The patient was a 74-year-old Chinese woman with sequential lymphadenopathy in the right and left cervical regions over a period of 2 months. The first biopsy revealed in situ follicular lymphoma with progressive transformation of germinal centers, and the biopsy of the second lymph node led to a diagnosis of in situ follicular lymphoma. The immunophenotype, polymerase chain reaction amplification of the immunoglobulin heavy chain gene, and fluorescence in situ hybridization for t(14;18) were analyzed in each biopsy specimen, which showed both specimens to have t(14;18)(q32;q21) and revealed progression from polyclonality to monoclonality. These findings suggest a case of multicentric in situ follicular lymphoma and provide new insights into the pathogenesis of this disease.