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.

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.

Primary Intestinal Extranodal Natural Killer/T-Cell Lymphoma, Nasal Type: A Comprehensive Clinicopathological Analysis of 55 Cases.

PURPOSE: To investigate the clinicopathological features, survival and prognostic factors of primary intestinal extranodal natural killer/T-cell lymphoma, nasal type (PI-ENKTCL). METHODS: Clinical and histological characteristics of PI-ENKTCL cases were retrospectively evaluated. Immunohistochemical phenotype and status of Epstein-Barr virus (EBV) and T-cell receptor (TCR) gene rearrangement were examined. The overall survival and prognostic parameters were also analyzed. RESULTS: Fifty-five (2.7%) cases with PI-ENKTCL were identified out of 2017 archived ENKTCL cases, with a median age of 39 years and a male to female ratio of 2.1:1. The most common symptom was abdominal pain (90.9%), accompanied frequently with fever and less commonly with intestinal perforation or B symptoms. Small intestine (50.9%) was the most common site to be involved. 47.3% and 36.4% cases presented with stage I and II diseases, respectively. Histologically, most cases displayed characteristic morphologic changes of ENKTCL. Cytoplasmic CD3, TIA-1 and CD56 expression was found in 100%, 94.5% and 89.1% of cases, respectively. In situ hybridization detection for EBV demonstrated positive results in all cases. Monoclonal TCR gene rearrangement was found in 52.9% of tested cases. Chemotherapy with a DICE or L-asparaginase/peg-asparginase-containing regimen was most often employed. Both advanced tumor stage and B symptoms were independent inferior prognostic factors (p = 0.001 and p = 0.010). Noticeably, 6 cases demonstrated a CD4-positive phenotype. These cases featured a relatively older median age (58 years), predominance of small/medium-sized neoplastic cells, a higher rate of TCR rearrangement and slightly favorable outcome. CONCLUSION: We reported by far the largest series of PI-ENKTCL, and demonstrated its heterogeneity, aggressive clinical behavior and unsatisfying response to the current therapeutic strategies. Those CD4-positive cases might represent a unique subtype of PI-ENKTCL or distinct entity. Further investigations are required for the better understanding and management of this unusual disease.

A case of PSF-TFE3 gene fusion in Xp11.2 renal cell carcinoma with melanotic features.

Xp11.2 translocation renal cell carcinoma (Xp11.2 RCC) with PSF-TFE3 gene fusion is a rare neoplasm. Only 22 cases of Xp11.2 RCCs with PSF-TFE3 have been reported to date. We describe an additional case of Xp11.2 RCC with PSF-TFE3 showing melanotic features. Microscopically, the histologic features mimic clear cell renal cell carcinoma. However, the dark-brown pigments were identified and could be demonstrated as melanins. Immunohistochemically, the tumor cells were widely positive for CD10, human melanoma black 45, and TFE3 but negative for cytokeratins, vimentin, Melan-A, microphthalmia-associated transcription factor, smooth muscle actin, and S-100 protein. Genetically, we demonstrated PSF-TFE3 fusion between exon 9 of PSF and exon 5 of TFE3. The patient was free of disease with 50 months of follow-up. The prognosis of this type of tumor requires more cases because of limited number of cases and follow-up period. Xp11.2 RCC with PSF-TFE3 inevitably requires differentiation from other kidney neoplasms. Immunohistochemical and molecular genetic analyses are essential for accurate diagnosis.

[Clinical significance of new classification of gastroenteropancreatic neuroendocrine neoplasms].

Gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs) are a group of tumors derived from diffuse neuroendocrine cells of the digestive system. All GEP-NEN shave potential malignancy. According to the WHO classification (2010), GEP-NENs can be divided into well differentiated neuroendocrine tumor (NET) and poorly differentiated neuroendocrine carcinoma (NEC). GEP-NEN scan be grouped into three grades: G1 , G2 and G3. The new WHO classification unifies the diagnostic terms and avoids the confusion of the nomenclature and classification of GEP-NENs,which is the foundation of clinical treatment and prognostic estimation.

[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.

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.

Clinical and pathological characteristics of giant cell angioblastoma: a case report.

Giant cell angioblastoma (GCAB) is an extremely rare soft tissue tumor of early childhood and only five cases have been described to date. As such the clinical, pathological, and prognostic features are poorly defined. We prensent here a new case of GCAB in bone of a child aged 4-years old. The lesion was composed of dense and loose cell regions. The dense regions were characterized by nodular, linear, and plexiform aggregates of oval- to spindle-shaped tumor cells around small vascular channels and interspersed with large mononuclear cells and multinucleate giant cells. The loose cell areas were characterized by distributed fibroblasts and abundant myxoid matrix, which diminished with patient age. Infiltrative growth was observed in some areas. Oval-to-spindle cells showed positivity for Vimentin, CD31 and CD34 staining, and partial positivity for smooth muscle actin. Mononuclear cells and multinucleate giant cells showed Vimentin and CD68 positivity. Seventeen months after thorough curettage of the lesion, a local recurrence was found. Based upon the clinical, histological and immunohistochemical findings, infiltrate condition, and prognosis, we classified GCAB into two subtypes. Type I does not infiltrate surrounding tissues and has good prognosis. Type II infiltrates the surrounding tissues, relapses earlier, and has worse prognosis. This report augments the limited GCAB literature to promote our understanding and guide therapy of this rare disease. VIRTUAL SLIDES: The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/6699811297488137.

[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.

Synchronous and metachronous multiple gastrointestinal stromal tumors.

BACKGROUND & AIMS: Sporadic multiple gastrointestinal stromal tumors (GISTs) are rare events especially those developed metachronously. This study aimed to investigate the clinico-pathologic and genetic features defining multiple GISTs. METHODS: 624 cases of GISTs were retrieved for retrospective review. 15 cases were identified as multiple GISTs including 13 synchronous and 2 metachronous ones. 32 tumors and 15 normal tissues were obtained from these cases each containing 2-3 tumor nodules and the genomic DNA was extracted for mutational analysis of KIT and PDGFRA genes. The associated patients were recruited for clinical follow-up studies, including 5 males and 10 females at 49 to 84 years of age. RESULTS: Multiple GISTs comprised of 2.4% of GIST cases in our consecutive series. Twenty-six tumors showed mutations at KIT gene in exon 11 and one at PDGFRA gene in exon 18. In seven synchronous cases, different tumors from the same patients displayed different genotypes of KIT or PDGFRA, suggesting their polyclonal origin. In the two multiple GISTs occurring metachronously, the tumors from each patient showed different KIT mutations, suggesting that the second tumors were not the relapse or metastasis of the primary GISTs. CONCLUSIONS: Based on types of KIT or PDGFRA mutations and other pathological features, multiple primary GISTs can be differentiated from multiple GISTs resulting from recurrence or metastasis of a single primary tumor. Unlike recurrence or metastasis of GISTs that are malignant, most multiple GISTs are mostly benign and do not require aggressive adjuvant therapy. Therefore, correct diagnosis is critical for proper treatment.

New prognostic parameters for very-low-risk gastrointestinal stromal tumors.

BACKGROUND: According to the National Institutes of Health consensus criteria, gastrointestinal stromal tumors (GISTs) smaller than 2 cm in diameter with less than 5 mitotic figures per 50 high-power fields are considered very-low-risk GISTs, but these two indices alone cannot reliably predict a benign outcome during long-term follow-ups. Therefore, identification of additional parameters for predicting the clinical behavior of GISTs is necessary. METHODS: Eighty-eight patients with tumors that meet the very-low-risk GIST criteria were retrospectively investigated and morphological parameters of tumors associated with the biological behavior of very-low-risk GISTs were evaluated in the present study. The Kaplan-Meier method was used to calculate disease-free survival rates. RESULTS: Eighty-one patients were followed up for one to 16.3 years. Five cases of relapses were identified in the patients. Distinctive infiltrative growth patterns such as muscularis propria, muscularis mucosa, or nerve infiltration were identified by microscopy in 4 patients with the relapse, including three patients who experienced multiple recurrences. The infiltrative growth features became more obvious in multiple recurrent tumors compared to the single recurrent tumor, while only one developed relapse in 76 patients without infiltration (P < 0.0001). CONCLUSION: Microscopic infiltrative growth patterns of the tumor may have clinical significance in predicting the prognosis of very-low-risk GISTs.