NR1D1-rearranged soft tissue tumour: A clinicopathological and molecular analysis of four additional cases.

AIMS: Nuclear receptor subfamily 1 group D member 1 (NR1D1)-rearranged soft tissue tumour is a newly described entity with an epithelioid morphology and a potential for aggressive behaviour. Largely due to under-recognition, this tumour type has not yet been widely acknowledged. Herein, we report four additional cases to further expand its clinicopathological and molecular spectrum. METHODS AND RESULTS: Four mesenchymal tumours with NR1D1 rearrangement were identified from our consultation files. There were one male and three females with ages ranging from 19 to 47 years (median = 28.5 years). Tumour occurred in the tongue, neck, hip and index finger, respectively. Histologically, two tumours were composed predominantly of epithelioid cells; one tumour had admixed epithelioid-spindle cells and one tumour consisted of monomorphic small round to ovoid cells. By immunohistochemistry, none of the tumours expressed lineage-specific markers. Targeted RNA-sequencing identified NR1D1 fusions in all four tumours, the partner genes being MAML2, MAML3, KMT2A and NCOA2, respectively. The novel MAML3 and NCOA2 rearrangements were confirmed by fluorescence in-situ hybridisation analysis. On follow-up (2-23 months), one patient experienced local recurrence due to incomplete resection and one patient developed lung metastasis. The other two patients were alive without disease. CONCLUSIONS: This study adds more support for NR1D1-rearranged soft tissue tumour as an emerging entity. The occurrence of two additional tumours in the head and neck region, description of a small round cell variant and identification of novel MAML3, KMT2A and NCOA2 partners further expand its clinicopathological and molecular spectrum. More studies on larger series are necessary to validate the fully malignant potential of NR1D1-rearranged soft tissue tumour.

A clinicopathological study and survival analysis of 99 breast cancers with HER2/CEP17 ratio ≥ 2.0 and an average HER2 copy number < 4.0 per cell in China.

BACKGROUND: Breast cancer patients of American Society of Clinical Oncology and the College of American Pathologists (ASCO/CAP) Group 2 were all HER2-negative according to the 2018 guideline, not HER2-positive as defined in the 2013 guideline. METHODS: We aims to elucidate the unique clinicopathological features of ASCO/CAP Group 2 patients by comparing with classic HER2-nonamplified cancers, and reveal the efficacy of the former to anti-HER2 therapy. The clinicopathological features, treatment and prognosis information of 99 patients between 2014 and 2018 were collected. HER2 status was re-defined using the updated recommendations. RESULTS: Of the 99 ASCO/CAP Group 2 tumors, 25.5% (25/99) tumors were immunohistochemical (IHC) 0/1+ and 74.7% (74/99) tumors were IHC 2+. According to the updated 2018 guideline, all of them were HER2 negative. When compared to ASCO/CAP Group 5, patients of ASCO/CAP Group 2 displayed higher ratio of histological grade 3 (P = .03), high Ki67 proliferation index (P = .03) and pN3 (more than 9 lymph nodes metastasis, P = .02), and lower estrogen receptor (ER) positivity (P = .04). There was no statistical difference in the survival of patients received anti-HER2 therapy and patients not received anti-HER2 therapy. CONCLUSIONS: Patients of ASCO/CAP Group 2 did not received apparent benefit from anti-HER2 treatment. Although according to the updated guidelines and latest reports, HER2 is negative, but when compared with classic HER2-nonamplified cancers, patients of this group seemed to be more aggressive. We suggest that this group still be regarded as an independent category, in order to accumulate more cases in the future to expand the scope of research.

Comprehensive analysis of cancer of unknown primary and recommendation of a histological and immunohistochemical diagnostic strategy from China.

BACKGROUND: Previous studies on cancer of unknown primary (CUP) mainly focus on treatment and prognosis in western populations and lacked clinical evaluation of different IHC markers, so this study aimed to evaluate characteristics of CUP and recommend a diagnostic strategy from a single center in China. METHODS AND RESULTS: Data of 625 patients with CUP were retrospectively collected and reviewed. The patients ranged in age from 20 to 91 years, with a female-to-male ratio of 1.3:1. The predominant histological type was poor or undifferentiated adenocarcinomas (308; 49.3%). The results of Canhelp-Origin molecular testing for the identification of the tissue of origin in 262 of 369 patients (71.0%) were considered predictable (similarity score > 45), with the most common predicted primary tumor site being the breast (57, 21.8%). Unpredictable molecular results correlated with more aggressive clinical parameters and poor survival. Thee positivity rates of several targeted antibodies (GATA3, GCDFP15, TTF1, Napsin A, and PAX8), based on the clinically predicted site, were lower than those reported for the corresponding primary tumors. Nonetheless, TRPS1 and INSM1 were reliable markers of predicted breast carcinoma (75.0%) and neuroendocrine tumors (83.3%), respectively. P16 expression, as well as HPV and EBER testing contributed significantly to the diagnosis of squamous cell carcinomas. Survival analysis revealed that older ages (> 57), ≥ 3 metastatic sites, non-squamous cell carcinomas, bone/liver/lung metastases, unpredictable molecular results, and palliative treatment correlated with poor overall survival. CONCLUSIONS: We recommend a CUP diagnostic strategy involving the use of targeted antibody panels as per histological findings that is potentially applicable in clinical practice. The markers TRPS1, INSM1, and P16 expression, as well as HPV and EBER testing are particularly valuable in this aspect. Molecular testing is also predictive of survival rates.

Radiogenomic Signatures of Oncotype DX Recurrence Score Enable Prediction of Survival in Estrogen Receptor-Positive Breast Cancer: A Multicohort Study.

Background Radiogenomics explores the association between imaging features and genomic assays to uncover relevant prognostic features; however, the prognostic implications of the derived signatures remain unclear. Purpose To identify preoperative radiogenomic signatures of estrogen receptor-positive breast cancer associated with the Oncotype DX recurrence score (RS) and to evaluate whether they are biomarkers for survival and responses to neoadjuvant chemotherapy (NACT). Materials and Methods In this retrospective multicohort study, three data sets were analyzed. The radiogenomic development data set, with preoperative dynamic contrast-enhanced MRI and RS data obtained between January 2016 and October 2019 was used to identify radiogenomic signatures. Prognostic implications of the imaging signatures were assessed by measuring overall survival and recurrence-free survival in the prognostic assessment data set using a multivariable Cox proportional hazards model. The therapeutic implication of the radiogenomic signatures was evaluated by determining their ability to predict the response to NACT using the treatment assessment data set obtained between August 2015 and March 2019. Prediction performance was estimated by using the area under the receiver operating characteristic curve (AUC). Results The final cohorts included a radiogenomic development data set with 130 women (mean age, 52 years ± 10 [standard deviation]), a prognostic assessment data set with 116 women (mean age, 48 years ± 9), and a treatment assessment data set with 135 women (mean age, 50 years ± 11). Radiogenomic signatures (n = 11) of texture and morphologic and statistical features were identified to generate the predicted RS (R2 = 0.33, P < .001). A predicted RS greater than 29.9 was associated with poor overall and recurrence-free survival (P = .001 and P = .007, respectively); predicted RS was greater in women with a good NACT response (30.51 ± 6.92 vs 27.35 ± 4.04 [responders vs nonresponders], P = .001). By combining the predicted RS and complementary features, the model achieved improved performance in prediction of the NACT response (AUC, 0.85; P < .001). Conclusion Radiogenomic signatures associated with genomic assays provide markers of prognosis and treatment in estrogen receptor-positive breast cancer. © RSNA, 2021 Online supplemental material is available for this article.

Concordance of the 21-gene assay between core needle biopsy and resection specimens in early breast cancer patients.

BACKGROUND: Adjuvant therapy decisions may be partly based on the results of a multigene quantitative reverse transcription-polymerase chain reaction (RT-PCR)-based assay: the 21-gene recurrence score (RS) test of resection specimens. When necessary, core needle biopsy (CNB) may be considered as a surrogate. Here, we evaluated the concordance in gene expression according to results from RT-PCR-based RS testing between paired CNBs and resection specimens. METHODS: CNBs and resection specimens from 50 breast cancer (BC) patients were tested to calculate RSs. First, we examined the concordance of the ER, PR and HER-2 status of tissue samples indicated by immunohistochemical (IHC) and RT-PCR analyses. Then, we compared the IHC findings of ER, PR, HER-2 and Ki-67 staining across paired samples. Ultimately, the RS and single-gene results for ER, PR, HER-2 and Ki-67 were explored between paired samples. RESULTS: The concordance between IHC and RT-PCR was 100%, 80.0% and 100% for ER, PR and HER-2, respectively, in both resection specimens and CNBs. The concordance for IHC ER, PR, HER-2 and Ki-67 status was 100%, 94.0%, 52.0% and 82.0%, respectively, between paired samples. RS results from paired samples showed a strong correlation. The overall concordance in RS group classification between samples was 74%, 72% and 78% based on traditional cutoffs, TAILORx cutoffs and ASCO guidelines, respectively. ER, PR, HER-2 and Ki-67 were modestly- to- strongly correlated between paired samples according to the RT-PCR results. CONCLUSION: A modest- to- strong correlation of ER, PR, HER-2 and Ki-67 gene expression and RS between CNBs and resection specimens was observed in the present study. The 21-gene RS test could be reliably performed on CNBs. ER, PR and HER-2 status showed remarkable concordance between the IHC and RT-PCR analyses. The concordance between paired samples was high for the IHC ER, PR and Ki-67 results and low for HER-2.

Inhibition of LXR signaling by SULT2B1b promotes liver regeneration after partial hepatectomy in mouse models of nonalcoholic fatty liver disease.

Hydroxysteroid sulfotransferase 2B1b (SULT2B1b) plays a critical role in hepatic energy homeostasis. Liver X receptors (LXRs) are implicated in multiple physiological functions, including the inhibition of hepatocyte proliferation and regulation of fatty acid and cholesterol metabolism. We have previously reported that SULT2B1b promotes hepatocyte proliferation by inactivating LXR signaling in vivo and in vitro, leading to our hypothesis that SULT2B1b promotes fatty liver regeneration. In the present study, female C57BL/6 and S129 mice were fed a high-fat diet for 8 wk to establish a nonalcoholic fatty liver disease (NAFLD) mouse model. 70% partial hepatectomy (PH) was performed to induce liver regeneration. Our experiments revealed that the SULT2B1b overexpression significantly promotes the regeneration of hepatocytes in NAFLD C57BL/6 mice after PH, increasing liver regrowth by 11% within 1 day, and then by 21%, 33%, and 24% by 2, 3, and 5 days post-PH, respectively. Compared with the wild-type NAFLD S129 mice, SULT2B1 deletion NAFLD S129 mice presented reduced hepatocyte regeneration at postoperative day 2, as verified by decreased liver regrowth (37.4% vs. 46.1%, P < 0.05) and the results of immunohistochemical staining, quantitative real-time polymerase chain reaction, and Western blot analysis. Moreover, LXRα signaling and SULT2B1b expression are highly correlated in the regeneration of NAFLD mouse liver; SULT2B1b overexpression suppresses LXRα signaling, while the LXRα-signaling agonist T0901317 blocks SULT2B1b-induced hepatocyte regeneration in NAFLD mouse liver. Thus, the upregulation of SULT2B1b may promote hepatocyte regeneration via the suppression of LXRα activation in NAFLD mice, providing a potential strategy for improving hepatic-steatosis-related liver regeneration disorders.NEW & NOTEWORTHY This study demonstrates for the first time that hydroxysteroid sulfotransferase 2B1b (SULT2B1b) overexpression promotes the regeneration of fatty liver after partial hepatectomy in mice with nonalcoholic fatty liver disease, while reducing triglyceride accumulation in the regenerative fatty liver. Liver X receptor signaling may be crucial in the SULT2B1b-mediated regeneration of fatty liver. Thus, SULT2B1b may be a potential target for treating hepatic steatosis-related liver regeneration disorders.

Intense basolateral membrane staining indicates HER2 positivity in invasive micropapillary breast carcinoma.

Invasive micropapillary carcinoma is characterized by the inside-out growth of tumor clusters and displays incomplete membrane immunostaining of HER2. According to the 2018 American Society of Clinical Oncology and the College of American Pathologists (ASCO/CAP) HER2-testing recommendation, moderate to intense but incomplete staining could be scored as immunohistochemical 2+. Furthermore, the criteria of immunohistochemical 3+ for this staining pattern are not mentioned. One hundred and forty-seven cases of invasive micropapillary carcinoma with moderate-to-intense HER2 immunostaining were enrolled. Invasive micropapillary carcinoma components of all cases were scored as immunohistochemical 2+ based on the 2018 ASCO/CAP recommendation. The invasive micropapillary carcinoma component varied from 10% to 100% (mean, 80%). Invasive micropapillary carcinoma components of all 147 tumors exhibited reversed polarity and incomplete basolateral HER2 membrane staining. One hundred and seventeen of the tumors (80%, 117/147) had moderate staining, and 38 (32%, 38/117) showed HER2 gene amplification by fluorescence in-situ hybridization. HER2 gene was amplified in all the remaining 30 tumors (20%, 30/147) that exhibited intense basolateral membrane staining. Besides, average HER2 signals per cell and ratio of HER2/CEP17 were significantly higher in the intense-staining tumors compared with the moderate-staining tumors (p < 0.0001). Follow-up data were available for 140 patients. None of the patients were died. The follow-up time ranged from 1 month to 99 months (median, 57 months). Thirteen (9%, 13/140) patients exhibited disease progression (recurrence or metastasis). HER2 gene amplification was correlated inversely with estrogen receptor (p = 0.000) and progesterone receptor (p = 0.000) expression, and positively with histological grade (p = 0.003) and disease progression (p = 0.000). Invasive micropapillary carcinoma with intense clear linear basolateral membrane immunostaining indicates HER2 positivity, even if the staining is incomplete. They should be classified as immunohistochemical 3+ rather than immunohistochemical 2+, which would avoid further fluorescence in-situ hybridization-testing procedure and greatly save the related time, labor, and financial costs. Ultimately, ensure all patients with HER2 gene amplification obtain effective targeted therapy in time.

High prevalence of ROS1 gene rearrangement detected by FISH in EGFR and ALK negative lung adenocarcinoma.

ROS1 rearrangement has become an important biomarker for targeted therapy in advanced lung adenocarcinoma (LUAD). The study aimed to evaluate the prevalence of ROS1 rearrangement in Chinese LUAD with EGFR wild-type and ALK fusion-negative status, and analyze the relationship with their clinicopathological characteristics. A large cohort of 589 patients of LUAD with EGFR/ALK wild-type, diagnosed between April 2014 and June 2018, was retrospectively analyzed. ROS1 rearrangement in all these cases was detected by FISH, and 8 selected cases with different positive and negative signals were confirmed by NGS. As a result, total of 56 cases with ROS1 rearrangements out of 589 LUADs (9.51%) were identified by FISH. The frequency of ROS1 rearrangement in women was 22.15% (35/158), which was statistically higher than 4.87% (21/431) in men (P < 0.001). The ROS1 positive rate in the patients with age < 50 years old (25.29%, 22/87) was statistically higher than that in the patients with age ≥ 50 (6.77%, 34/502) (P < 0.001). There was a trend that the frequency of ROS1 rearrangement in LUAD with stage III-IV was higher than that in stage I-II (9.56%, 39/408 vs 2.50%, 1/40), although it did not reach significant difference (P = 0.135). 37 out of 56 cases of ROS1 rearranged LUAD showed solid (n = 20, 35.71%) and invasive mucinous adenocarcinoma (n = 17, 30.36%) pathological subtypes. The median OS for patients of ROS1 rearranged LUAD treated with TKIs (n = 29) was 49.69 months (95% CI: 36.71, 62.67), compared with 32.55 months (95% CI: 23.24, 41.86) for those who did not receive TKI treatment (n = 16) (P = 0.040). The NGS results on ROS1 rearrangement in all the 8 cases were concordant with FISH results. In conclusion, high prevalence of ROS1 rearrangements occurs in EGFR/ALK wild-type LUAD detected by FISH, especially in younger, female, late stage patients, and in histological subtypes of solid and invasive mucinous adenocarcinoma.

Integrative analysis of PD-L1 DNA status, mRNA status and protein status, and their clinicopathological correlation, in diffuse large B-cell lymphoma.

AIMS: The protein expression of programmed death-ligand 1 (PD-L1) has been recognised as being a biomarker for poor prognosis in diffuse large B-cell lymphoma (DLBCL). The aims of this study were to determine PD-L1 DNA status and mRNA status, and to explore whether they contribute to protein expression and their clinicopathological correlation in DLBCL. METHODS AND RESULTS: In this study, we used fluorescence in-situ hybridisation, RNA in-situ hybridisation and immunohistochemistry to determine PD-L1 status at three different levels in 287 DLBCL samples with follow-up. Their correlation and clinical pathological relevance were also analysed. Our results showed that 1.7% (3/175) of patients had PD-L1 DNA amplification, 19.9% (57/287) had high PD-L1 mRNA expression, and 11.8% (34/287) had high PD-L1 protein expression. Both mRNA and protein expression of PD-L1 were significantly higher in non-germinal centre B-cell-like (GCB) DLBCL than in GCB DLBCL (P < 0.05). In addition, the patients with high PD-L1 mRNA or high PD-L1 protein expression but no PD-L1 DNA amplification had significantly poorer overall survival (OS) than those with low PD-L1 expression (P < 0.05). Furthermore, we found that PD-L1 mRNA and PD-L1 protein expression were highly correlated (P = 0.012), which was observed in all three samples with DNA amplification. CONCLUSIONS: PD-L1 DNA amplification is a rare event, PD-L1 mRNA is the main contributor to the high PD-L1 protein expression, and the latter two will serve as important biomarkers for predicting the prognosis of DLBCL patients and selecting them for immunotherapy.

Molecular profiling of the biphasic components of hepatic carcinosarcoma by the use of targeted next-generation sequencing.

AIMS: To better understand the tumourogenesis and molecular features of hepatic carcinosarcoma (HCS). METHODS AND RESULTS: We selected 13 cases of HCS, including the clinicopathological and immunohistochemical features, and analysed the molecular alterations in separately microdissected carcinomatous and sarcomatous components in eight cases by using targeted next-generation sequencing with a panel of 329 cancer-related genes. As a result, transitional areas were observed between the two components of HCS in all cases. Concordance and overlap in genetic alterations were identified in the two histological components of the eight HCS patients, indicating the clonal relatedness of the two tumour components. The most common gene alterations found in both components were TP53 (75%, 6/8) and NF1/2 (38%, 3/8) mutations and VEGFA amplification (25%, 2/8), which may be strongly associated with HCS tumorigenesis. Unique mutations and amplifications found only in one component were also identified. Amplifications involving MET (38%, n = 3/8) and PDGFRA (25%, n = 2/8) were present only in the sarcomatous components, whereas mutation affecting ERBB4 (25%, n = 2/8) and amplifications of CCND1 and FGF3/4/19 (38%, n = 3/8) were present only in the carcinomatous components, indicating their involvement in the clonal evolution of HCS. Furthermore, multiple potential therapeutic targets were identified for HCS. CONCLUSIONS: Our findings indicate that HCS could have been of monoclonal origin, and that the diverse clonal evolution might be driven by special molecular alterations in each tumour component. Our results also identify multiple therapeutic targets of HCS, which are valuable for the personalised treatment of HCS.

Differentiation of triple-negative breast cancer from other subtypes through whole-tumor histogram analysis on multiparametric MR imaging.

PURPOSE: To identify triple-negative (TN) breast cancer imaging biomarkers in comparison to other molecular subtypes using multiparametric MR imaging maps and whole-tumor histogram analysis. MATERIALS AND METHODS: This retrospective study included 134 patients with invasive ductal carcinoma. Whole-tumor histogram-based texture features were extracted from a quantitative ADC map and DCE semi-quantitative maps (washin and washout). Univariate analysis using the Student's t test or Mann-Whitney U test was performed to identify significant variables for differentiating TN cancer from other subtypes. The ROC curves were generated based on the significant variables identified from the univariate analysis. The AUC, sensitivity, and specificity for subtype differentiation were reported. RESULTS: The significant parameters on the univariate analysis achieved an AUC of 0.710 (95% confidence interval [CI] 0.562, 0.858) with a sensitivity of 63.6% and a specificity of 73.1% at the best cutoff point for differentiating TN cancers from Luminal A cancers. An AUC of 0.763 (95% CI 0.608, 0.917) with a sensitivity of 86.4% and a specificity of 72.2% was achieved for differentiating TN cancers from human epidermal growth factor receptor 2 (HER2) positive cancers. Also, an AUC of 0.683 (95% CI 0.556, 0.809) with a sensitivity of 54.5% and a specificity of 83.9% was achieved for differentiating TN cancers from non-TN cancers. There was no significant feature on the univariate analysis for TN cancers versus Luminal B cancers. CONCLUSIONS: Whole-tumor histogram-based imaging features derived from ADC, along with washin and washout maps, provide a non-invasive analytical approach for discriminating TN cancers from other subtypes. KEY POINTS: • Whole-tumor histogram-based features on MR multiparametric maps can help to assess biological characterization of breast cancer. • Histogram-based texture analysis may predict the molecular subtypes of breast cancer. • Combined DWI and DCE evaluation helps to identify triple-negative breast cancer.

Hydroxysteroid sulfotransferase 2B1 affects gastric epithelial function and carcinogenesis induced by a carcinogenic agent.

BACKGROUND: A healthy gastric mucosal epithelium exhibits tumor-suppressive properties. Gastric epithelial cell dysfunction contributes to gastric cancer development. Oxysterols provided from food or cholesterol oxidation in the gastric epithelium may be further sulfated by hydroxysteroid sulfotransferase 2B1 (SULT2B1), which is highly abundant in the gastric epithelium. However, the effects of SULT2B1 on gastric epithelial function and gastric carcinogenesis are unclear. METHODS: A mouse gastric tumor model was established using carcinogenic agent 3-methylcholanthrene (3-MCA). A SULT2B1 deletion (SULT2B1-/-) human gastric epithelial line GES-1 was constructed by CRISPR/CAS9 genome editing system. RESULTS: The gastric tumor incidence was higher in the SULT2B1-/- mice than in the wild-type (WT) mice. In gastric epithelial cells, adenovirus-mediated SULT2B1b overexpression reduced the levels of oxysterols, such as 24(R/S),25-epoxycholesterol (24(R/S),25-EC) and 27-hydroxycholesterol (27HC). This condition also increased PI3K/AKT signaling to promote gastric epithelial cell proliferation, epithelization, and epithelial development. However, SULT2B1 deletion or SULT2B1 knockdown suppressed PI3K/AKT signaling, epithelial cell epithelization, and wound healing and induced gastric epithelial cell malignant transition upon 3-MCA induction. CONCLUSIONS: The abundant SULT2B1 expression in normal gastric epithelium might maintain epithelial function via the PI3K/AKT signaling pathway and suppress gastric carcinogenesis induced by a carcinogenic agent.

Upregulation of 24(R/S),25-epoxycholesterol and 27-hydroxycholesterol suppresses the proliferation and migration of gastric cancer cells.

Gastric cancer (GC) is one of the most common cancers and is the second-leading cause of cancer-associated morbidity worldwide. Oxysterols are oxidized derivatives of cholesterol that may be important in many biological processes, but the levels and roles of oxysterols in gastric tumours remain to be elucidated. The levels of cholesterol, oxysterols and sulfated oxysterols in human gastric tumour tissues, adjacent normal mucosal tissues, cancerous gastric juice and gastric juice obtained from healthy subjects were detected by LC-MS. It was found that the levels of 24(R/S),25-EC and 27HC in human gastric tumour tissues and cancerous gastric juice were significantly increased compared with those of adjacent normal mucosal tissues and gastric juice from healthy subjects. Compared with normal gastric mucosal tissue, the levels of sulfated 25-hydroxycholesterol (25HC3S) and the ratio of 25HC3S/25HC were decreased in human gastric tumour tissues, which might be related to the dramatically decreased SULT2A1 expression in gastric tumour tissue. Both 24(R/S),25-EC and 27HC suppressed gastric cancer proliferation, which was not altered by LXRα-siRNA treatment. The suppression of cell proliferation induced by 27HC was attenuated by LXRß-siRNA, but the suppression of cell proliferation induced by 24(R/S),25-EC was intensified by LXRß-siRNA. Both 24(R/S),25-EC and 27HC dramatically inhibited HGC-27 cell migration, which was attenuated by the co-transfection of cells with LXRα-siRNA and LXRß-siRNA, but not LXRα-siRNA or LXRß-siRNA alone. In conclusion, the accumulated 24(R/S),25-EC and 27HC in human gastric tumour tissues might play important roles in gastric cancer development.

Secretory breast carcinoma with a papillary-predominant pattern: an unusual morphological variant.

AIMS: Secretory breast carcinoma is a rare, low-grade, translocation-associated invasive carcinoma with unique morphology and excellent prognosis. Three patterns (microcystic, tubular, solid) have often been described in secretory carcinoma. Herein, we reported one case of secretory breast carcinoma with an uncommon papillary-predominant growth pattern. METHODS AND RESULTS: The patient was a 53-year-old female with a mass located in outer upper quadrant of her right breast. The patient had one positive axillary lymph node. Morphologically, tumour cells were arranged in a papillary growth pattern with sclerosis in most areas; glandular and microcystic patterns were observed only in focal areas at the periphery. The presence of intracellular and extracellular secretory material was observed. Tumour cells were mild-to-moderately atypical with granular eosinophilic to foamy cytoplasm. Tumour cells were triple-negative [negative for oestrogen receptor (ER), progestogen receptor (PR) and human epidermal growth factor receptor 2 (HER2)] with a basal-like phenotype, and strongly positive for S-100 protein. P63 and calponin staining showed the absence of myoepithelial cells around tumour cells. Fluorescence in-situ hybridization (FISH) analysis showed ETS variant 6 (ETV6) gene rearrangement. CONCLUSIONS: Our study indicated that besides typical growth patterns (microcystic, solid and tubular), secretory carcinoma could also present with a papillary-predominant architecture. These cases should be differentiated from other breast tumours with a papillary pattern. It may have clinical significance to recognize this uncommon morphology variant of secretory carcinoma in routine practice.

Pancreatic carcinosarcoma with the same KRAS gene mutation in both carcinomatous and sarcomatous components: molecular evidence for monoclonal origin of the tumour.

AIMS: To better understand the histogenesis, prognosis and feasible treatment of pancreatic carcinosarcoma, a rare type of neoplasia. METHODS AND RESULTS: We investigated eight additional cases of pancreatic carcinosarcoma at a single institution, including the clinicopathological, immunohistochemical, and KRAS mutation characteristics. We have also reviewed the current literature on this rare type of neoplasia, and summarized the clinicopathological features and feasible treatments. As a result, concordant strong nuclear immunoreactivity for P53 protein and the same type of KRAS gene mutation, c.35G>A (p.G12D) or c.35G>T (p.G12V), were showed in both carcinomatous and sarcomatous components in five of eight cases. Furthermore, we found that the patients treated with surgery plus postoperative chemotherapy had longer survival than those treated with surgery only (P = 0.034 and P = 0.131 for overall survival and disease-free survival, respectively), although Cox regression multivariate analysis indicated that it was not an independent predictor. In addition, we found KRAS mutant allele-specific imbalance in four of our five cases of pancreatic carcinosarcoma, which was associated with advanced disease and a worse prognosis. CONCLUSIONS: This is the largest panel of cases of pancreatic carcinosarcoma studied so far, including clinicopathological, immunohistochemical and molecular cytogenetic features. Our findings indicate that the tumour could have been of monoclonal origin, and that the sarcomatous components might have arisen from metaplastic transformation of the carcinomatous components. Our results also suggest that surgery plus POC including gemcitabine may be a good choice for patients with pancreatic carcinosarcoma.

Specific immunohistochemical detection of the BRAF V600E mutation in primary and metastatic papillary thyroid carcinoma.

PURPOSE: To evaluate the clinical value of immunohistochemistry (IHC) using anti-BRAF V600E antibody (clone VE1) for specific detection of the BRAF V600E mutant protein in formalin-fixed paraffin-embedded papillary thyroid carcinoma (PTC) specimens. METHODS: A total of 118 PTC cases and 116 control cases processed between January 2008 and June 2010 were selected and created tissue microarrays (TMAs) for the study. BRAF V600E (VE1) IHC was performed on tissue sections from PTC cases to determine mutation status. Molecular tests (Sanger sequencing/ARMS) were used to confirm the BRAF V600E gene mutation in primary PTC. RESULTS: A uniformly cytoplasmic staining throughout the tumors was observed in IHC-positive cases. BRAF V600E was detected in 68.6% (81/118) of PTC samples by IHC and in 61.9% (73/118) by Sanger sequencing/ARMS. The overall concordance between IHC and Sanger sequencing/ARMS was 93.2% (110/118). The sensitivity and specificity of the BRAF V600E IHC was 100% (73/73) and 82.2% (37/45), respectively. Positive and negative predictive values were 90.1% (73/81) and 100% (37/37), respectively. Expression of the BRAF V600E mutant protein was detected in all of 59 cases of primary carcinoma and corresponding metastatic carcinoma in lymph nodes. The concordance between IHC staining in primary and metastatic PTC was 100% (59/59). CONCLUSION: IHC using VE1 antibody for detection of the BRAF V600E mutant protein expression in PTC showed high sensitivity and acceptable specificity, which are critical for diagnostic purposes. IHC staining for BRAF V600E showed uniformly cytoplasmic expression in both primary tumor and metastatic nodes. Therefore, IHC has high practical value for the detection of the BRAF V600E mutation in metastatic and primary PTC.

Microcystic stromal tumour of the ovary: frequent mutations of ß-catenin (CTNNB1) in six cases.

AIMS: To analyse the clinicopathological, immunohistochemical and ß-catenin (CTNNB1) mutation characteristics of six cases of microcystic stromal tumour of the ovary (MCST). METHODS AND RESULTS: Six Chinese patients with MCST who ranged in age from 29 to 69 years (mean 50 years) were included in the study. Five patients were detected with a pelvic mass during routine health examinations and one patient presented initially with opsomenorrhoea. All tumours involved the left ovary, with solid-cystic cut surface in five cases and cystic cut surface in one case. Microscopically, microcysts, solid nests and hyaline degenerated fibrous stroma were variably mixed. Immunohistochemically, the tumour cells in all cases were diffusely positive for CD10, vimentin and WT-1 and negative for α-inhibin and calretinin. ß-catenin expression was observed in both the nucleus and the cytoplasm in five cases and only in the cytoplasm in one case. The results of CTNNB1 mutation analysis revealed four missense point mutations in four cases, which were c.97T>C, c.101G>A, c.110C>G and c.122C>T. CONCLUSIONS: MCST shows a unique morphology with characteristic immunophenotype. ß-catenin expression in the nucleus and ß-catenin mutations were identified in the majority of cases, which suggests that the Wnt/ß-catenin pathway may play a crucial role in the tumorigenesis of MCST.

[Anaplastic lymphoma kinase-positive adenocarcinoma of lung: a cytopathologic analysis].

OBJECTIVE: To study the cytomorphologic features of anaplastic lymphoma kinase (ALK)-rearranged pulmonary adenocarcinoma. METHODS: The morphologic features in 153 pulmonary adenocarcinoma cytology specimens encountered during the period from September, 2011 to April, 2015 in Shanghai Cancer Hospital were retrospectively reviewed. Fluorescence in-situ hybridization (FISH) and/or immunohistochemistry (Ventana D5F3) for ALK gene rearrangement were carried out. The samples studied included 34 pleural effusion specimens, 40 endobronchial ultrasound-guided transbronchial needle aspirates (EBUS-TBNA) and 79 fine needle aspirates of palpable masses on body surface. RESULTS: Thirty-nine cases (25.5%) of ALK-rearranged samples were identified by FISH and/or immunohistochemistry, including 3 cases diagnosed by FISH and 36 cases by both technologies. The median age of the ALK-positive group was 50 years, significantly younger than that of the ALK-negative group (60 years old, P = 0.002). Only 4 of the ALK-positive patients were smokers, which was significantly less than that of the ALK-negative group (P < 0.01). In ALK-positive group, 3 cases showed cribriform pattern with prominent nucleoli, 3 cases showed cribriform pattern with mucin-rich cells and 8 cases showed extracellular mucus with mucin-rich cells. The above cytomorphologic patterns were significantly less common in ALK-negative tumors (P < 0.01). CONCLUSIONS: ALK-rearranged lung adenocarcinoma is associated with certain distinctive morphologic patterns, including cribriform architecture, presence of prominent nucleoli, mucin-rich cells and extracellular mucus, which can be observed in cytology specimens (including conventional smears and cell block sections). These findings, when combined with clinical features, may give clues to detection of ALK-positive cases.

Chinese expert consensus on clinical practice of MET detection in non-small cell lung cancer.

Mesenchymal epithelial transition (MET) factor alteration in non-small cell lung cancer (NSCLC) includes MET exon 14 skipping alteration (METex14 skipping), MET gene amplification, MET gene mutation (mainly kinase domain mutation), MET gene fusion, and MET protein overexpression. The incidence of METex14 skipping in patients with NSCLC is 0.9-4.0%. At present, drugs targeting METex14 skipping have been approved in China and other countries like Japan and USA. Patients with advanced NSCLC should undergo testing, including METex14 skipping, to screen the population with benefit from targeted therapy with MET inhibitors. The incidence of de novo MET gene amplification in NSCLC patients is 1-5%, the incidence of acquired MET gene amplification in epidermal growth factor receptor tyrosine kinase inhibitor (TKI)-resistant patients is 5-50%, and the incidence in anaplastic lymphoma kinase (ALK) TKI-resistant patients is about 13%; the incidence of MET protein overexpression in NSCLC patients is 13.7-63.7%. Several clinical trials on MET gene amplification and MET protein overexpression are ongoing, which have demonstrated their important guiding significance as biomarkers in the clinical treatment with MET inhibitors. Accurate detection of MET alterations is a prerequisite for MET inhibitor therapy. Since there are many types of MET alterations and related testing methods, as well as many problems and challenges during clinical testing, further sorting and standardization are required. Combined with clinical practice experience, literature review, and expert discussion, the writing group developed this consensus on the three main types of MET alterations (METex14 skipping, MET gene amplification, and MET protein overexpression) in order to guide the practical applications of clinical MET testing.