Correlation of ROS1 (D4D6) Immunohistochemistry with ROS1 Fluorescence In Situ Hybridization Assay in a Contemporary Cohort of Pulmonary Adenocarcinomas.

Sambit K. MohantyObjective Repressor of Silencing ( ROS1 ) gene rearrangement in the lung adenocarcinomas is one of the targetable mutually exclusive genomic alteration. Fluorescence in situ hybridization (FISH), immunohistochemistry (IHC), next-generation sequencing, and reverse transcriptase polymerase chain reaction assays are generally used to detect ROS1 gene alterations. We evaluated the correlation between ROS1 IHC and FISH analysis considering FISH as the gold standard method to determine the utility of IHC as a screening method for lung adenocarcinoma. Materials and Methods A total of 374 advanced pulmonary adenocarcinoma patients were analyzed for ROS1 IHC on Ventana Benchmark XT platform using D4D6 rabbit monoclonal antibody. FISH assay was performed in parallel in all these cases using the Vysis ROS1 Break Apart FISH probe. Statistical Analysis The sensitivity, specificity, positive and negative likelihood ratios, positive and negative predictive values, and accuracy were evaluated. Results A total of 17 tumors were positive either by IHC or FISH analysis or both (true positive). Four tumors were positive by IHC (H-score range: 120-270), while negative on FISH analysis (false positive by IHC). One tumor was IHC negative, but positive by FISH analysis (false negative). The sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, positive predictive value, negative predictive value, and accuracy were 94.4% (confidence interval [CI]: 72.71-99.86%), 63.6% (CI: 30.79-89.07%), 2.6 (CI: 1.18-5.72), 0.09 (CI: 0.01-0.62), 80.95% (CI: 65.86-90.35%), 87.5% (CI: 49.74-98.02%), and 82.76%, respectively. Conclusion ROS1 IHC has high sensitivity at a cost of lower specificity for the detection of ROS1 gene rearrangement. All IHC positive cases should undergo a confirmatory FISH test as this testing algorithm stands as a reliable and economic tool to screen ROS1 rearrangement in lung adenocarcinomas.

Primary round cell sarcomas of the urinary bladder with EWSR1 rearrangement: a multi-institutional study of thirteen cases with a review of the literature.

Primary Ewing sarcoma (ES) of the urinary bladder is a rare and aggressive small blue round cell malignant neoplasm associated primarily with translocation involving EWSR1 and FLI1 genes located in the 22nd and 11th chromosomes, respectively. To date, 18 cases have been published in the literature as single-case reports, based chiefly on CD99 positivity (17 patients). Molecular confirmation by fluorescence in situ hybridization was performed in 9 patients, and FLI1 immunohistochemical (IHC) analysis was not performed in any of these published cases. Herein, we present thirteen patients of more comprehensive primary round cell sarcomas of the urinary bladder with EWSR1 rearrangement. Clinicopathologic parameters including demographics; clinical presentation; histopathologic, IHC, and molecular profiles; and management and follow-up data of 13 patients with primary round cell sarcomas with EWSR1 rearrangement (Ewing family of tumor) of the urinary bladder were analyzed. The studied patients (n = 13) included 6 females and 7 males; their age ranged from 4 years to 81 years (median = 30 years). The most common clinical presentation was hematuria (n = 7), followed by hydronephrosis (n = 2, one with renal failure). The tumor size ranged from 2.9 cm to 15 cm in maximum dimension. Conventional ES architecture and histology was observed in 6 cases, and diverse histology was observed in 7 cases (adamantinomatous pattern [n = 1], alveolar pattern [n = 1], ganglioneuroblastoma-like pattern [n = 2], and small cell carcinoma-like pattern [n = 3]). All the tumors were muscle invasive (invasion into the muscularis propria). IHC analysis showed that all tumors expressed FLI1, CD99, and at least one neuroendocrine marker. Focal cytokeratin staining was positive in 2 patients, and RB1 was retained in all patients. EWSR1 rearrangement was seen in 12 of 12 tumors (in 12 patients) tested. A combined multimodal approach that included surgery with chemotherapy was instituted in all patients. Follow-up was available for 11 patients (ranging from 5 to 24 months). Six patients either died of disease (n = 3) or other causes (n = 3). Five patients were alive with metastases to the liver (n = 1), liver and lung (n = 2), liver and abdominal wall (n = 1), and kidney (n = 1). Based on our experience with the largest series to date and aggregate of the published data, ES/round cell sarcomas with EWSR1 rearrangement occurring in the bladder have bimodal age distribution with poor prognosis despite aggressive therapy. Owing to its rarity and age distribution, the differential diagnosis is wide and requires a systematic approach for ruling out key age-dependent differential diagnoses aided with molecular confirmation.

Chronic lymphocytic leukemia with a FGFR3 translocation: case report and literature review of an uncommon cytogenetic event.

The t(4;14) (p16; q32) with fusion of the IGH (immunoglobulin heavy chain) and FGFR3 (fibroblast growth factor receptor 3) genes are rarely present in patients with chronic lymphocytic leukemia (CLL), with only two previously reported cases. We herein describe a unique case of CLL with the occurrence of a t(4;14) (p16;q32), trisomy 12, and deletion of 11q13-q23 in the same clonal cells. In contrast to myeloma, in which FGFR3 translocations are a common early cytogenetic hit, FGFR3 rearrangement in CLL appears to occur later in the disease course.

Commercial laboratory testing of excision repair cross-complementation group 1 expression in non-small cell lung cancer.

Excision repair cross-complementation group 1 (ERCC1) expression by non-small cell lung cancer (NSCLC) has been reported to predict resistance to platinum-based therapies. On this basis, several commercial laboratories have offered ERCC1 testing to facilitate clinical decision making, but the reliability of such assays has recently been called into question. Methods. First, three large commercial laboratories were queried for their cumulative ERCC1 test results in NSCLC patients to compare their independent rates of ERCC1 expression. Second, identical tumor blocks from individual NSCLC patients underwent round-robin analysis to evaluate interlaboratory concordance for ERCC1 expression. Third, a retrospective review of medical records from NSCLC patients identified those who were both highly responsive and resistant to platinum-based chemotherapies. Tumor blocks from these patients were then used in a gold standard analysis to determine individual laboratory sensitivity and specificity for ERCC1 results. Results. Significant differences were observed in independent laboratory ERRC1 expression rates (Clarient 70% vs. Genzyme 60% vs. Third Laboratory 44%, p < .0001 for all two-way comparisons). Only 4 of 18 tumors examined in round-robin analysis were fully concordant (κ ≤ 0.222 for all two-way comparisons). In preselected platinum responsive and resistant specimens, none of these three commercially marketed laboratory assays achieved a specificity of greater than 50%. Conclusion. The results of commercial laboratory testing for ERCC1 are inconsistent and unreliable. Better validation and postmarketing surveillance should be mandated before tumor biomarker assays are allowed to enter the clinical arena.

A case of laparoscopic mesenteric cyst excision.

The objective of this study is to discuss the presentation, diagnosis, and surgical management of a young, healthy patient with a symptomatic mesenteric cyst. He had a 5-month history of abdominal pain from this disorder, and the case is presented to illustrate the clinical picture and operative management of this rare disorder.

Translocation renal cell carcinomas in adults: a single-institution experience.

Translocation renal cell carcinoma is a newly recognized subtype of renal cell carcinoma (RCC) with chromosomal translocations involving TFE3 (Xp11.2) or, less frequently, TFEB (6p21). Xp11 translocation RCC was originally described as a pediatric neoplasm representing 20% to 40% of pediatric RCCs, with a much lower frequency in the adult population. TFEB translocation RCC is very rare, with approximately 10 cases reported in the literature. Here, we describe the clinicopathologic features of adult translocation RCC from a single institution. Using tissue microarray, immunohistochemistry, cytogenetic examination, and fluorescence in situ hybridization, we identified 6 (∼5%) cases of TFE3 translocation RCC and 1 (<1%) case of TFEB translocation RCC in 121 consecutive adult RCC cases between 2001 and 2009. Our results suggest that weak TFE3 staining of a significant proportion of RCC cases may be because of expression of the full-length TFE3 protein rather than the chimeric fusion protein resulting from chromosomal translocation.

Radiology-pathology conference: primary perinephric and renal extraosseous Ewing's sarcoma.

Ewing's sarcoma/primitive neuroectodermal tumor is a rare entity belonging to a family of neoplasms of neuroectodermal origin. These highly aggressive neoplasms overwhelmingly affect children and young adults. A quarter of Ewing's sarcomas occur principally in the soft tissues with primary involvement of the perinephric fat and kidney being exceptionally rare. We present a 38-year-old man with primary Ewing's sarcoma of the perinephric fat and kidney diagnosed 2 years earlier who subsequently developed an infiltrating left renal and perinephric mass.

Intermittent FDG uptake in lipomatous hypertrophy of the interatrial septum on serial PET/CT scans.

We present a unique case of a patient with a clinical history of distal esophageal carcinoma and CT appearance of lipomatous hypertrophy of the interatrial septum who displayed fluorine-18-fluorodeoxyglucose (FDG) uptake in the interatrial septal fat on only the second of 4 serial PET/CT studies. As PET/CT scans are used for the initial staging of esophageal carcinoma, one should not mistake more benign causes of mediastinal uptake for metastasis when observing an intermittent pattern of uptake on a PET/CT scan.

Demonstration of a perihepatic abscess communicating with a fistula from the small bowel on hepatobiliary imaging.

Abscess formation after abdominal surgery is not an uncommon complication. It is much less common for a collection to be the result of a fistulous tract from the bowel. We describe a patient who underwent a Tc-99m hepatobiliary (Choletec) scan for the workup of a perihepatic abscess, which confirmed the presence of a fistulous tract from the small bowel to a perihepatic collection.

Compartment syndrome caused by computed tomography contrast infiltration seen on a Tc-99m methylene diphosphonate bone scan.

A 72-year-old man was hospitalized for transurethral resection of bladder cancer. Two days after the procedure, the patient continued to have gross hematuria and a computed tomography (CT) scan of the abdomen and pelvis with intravenous contrast was performed to check the integrity of the resection site. Later that day, the patient underwent technetium-99m methylene diphosphonate (MDP) bone scintigraphy to investigate the possibility of bone metastasis. The bone scan showed no signs of metastasis but did reveal increased uptake of the left hand and forearm on the opposite side of the injection site.

MRI features of Lyme arthritis of the hips.

Diagnosing Lyme arthritis without a history of travel to endemic regions or erythema migrans can be a challenge. Radiographic and ultrasonographic findings are nonspecific for the diagnosis of Lyme arthritis. We present the MRI features of Lyme disease of the hip in a 4-year-old boy who presented with hip pain and was found to have Lyme disease by Western blot. Our findings include bilateral hip effusions and synovial enhancement, normal bone marrow signal intensity without enhancement, minimal adjacent muscular and soft-tissue edema, and bilateral inguinal lymph nodes measuring up to 1 cm.

Sustained expansion of NKT cells and antigen-specific T cells after injection of alpha-galactosyl-ceramide loaded mature dendritic cells in cancer patients.

Natural killer T (NKT) cells are distinct glycolipid reactive innate lymphocytes that are implicated in the resistance to pathogens and tumors. Earlier attempts to mobilize NKT cells, specifically, in vivo in humans met with limited success. Here, we evaluated intravenous injection of monocyte-derived mature DCs that were loaded with a synthetic NKT cell ligand, alpha-galactosyl-ceramide (alpha-GalCer; KRN-7000) in five patients who had advanced cancer. Injection of alpha-GalCer-pulsed, but not unpulsed, dendritic cells (DCs) led to >100-fold expansion of several subsets of NKT cells in all patients; these could be detected for up to 6 mo after vaccination. NKT activation was associated with an increase in serum levels of interleukin-12 p40 and IFN-gamma inducible protein-10. In addition, there was an increase in memory CD8+ T cells specific for cytomegalovirus in vivo in response to alpha-GalCer-loaded DCs, but not unpulsed DCs. These data demonstrate the feasibility of sustained expansion of NKT cells in vivo in humans, including patients who have advanced cancer, and suggest that NKT activation might help to boost adaptive T cell immunity in vivo.

Vigorous premalignancy-specific effector T cell response in the bone marrow of patients with monoclonal gammopathy.

Most approaches targeting the immune system against tumors have focused on patients with established tumors. However, whether the immune system can recognize preneoplastic stages of human cancer is not known. Here we show that patients with preneoplastic gammopathy mount a vigorous T cell response to autologous premalignant cells. This preneoplasia-specific CD4+ and CD8+ T cell response is detected in freshly isolated T cells from the BM. T cells from myeloma marrow lack this tumor-specific rapid effector function. These data provide direct evidence for tumor specific immune recognition in human preneoplasia and suggest a possible role for the immune system in influencing the early growth of transformed cells, long before the development of clinical cancer.

Severe and selective deficiency of interferon-gamma-producing invariant natural killer T cells in patients with myelodysplastic syndromes.

Here we show that patients with myelodysplastic syndromes (MDS) have a severe deficiency of glycolipid reactive Valpha24+/Vbeta11+ natural killer T (NKT) cells, but not NK cells or CD4+ or CD8+ T cells. Neither the blood nor marrow of MDS patients had detectable interferon-gamma-producing NKT cells in response to the NKT ligand, alpha-galactosyl ceramide, although influenza-virus-specific effector T-cell function was preserved. This severe and selective deficiency of an important immune regulatory cell may contribute to the pathogenesis of MDS.

Expression of cancer/testis (CT) antigens MAGE-A1, MAGE-A3, MAGE-A4, CT-7, and NY-ESO-1 in malignant gammopathies is heterogeneous and correlates with site, stage and risk status of disease.

Cancer/testis (CT) antigens are expressed in several malignant tumors, but not in normal tissues except for testicular germ cells. The expression of CT antigenic proteins in malignant gammopathies has not been characterized. We examined the expression of a panel of CT antigenic proteins in 29 patients with malignant gammopathies by immunohistochemistry using the following monoclonal antibodies (mAbs): mAb MA454 to MAGE-A1, mAb M3H67 to MAGE-A3, mAb 57B to MAGE-A4, mAb CT7-33 to CT7/MAGE-C1 and mAb ES121 to NY-ESO-1. We could detect at least one CT antigen in tumors from 27 of 29 patients. The expression pattern of MAGE-A1, -A3, -A4 and NY-ESO-1 is heterogeneous in most cases, revealing staining in <25% of the tumor cells. Monoclonal antibodies CT7-33 and M3H67 show the highest incidence of immunoreactivity. Importantly, CT-7 can also be detected on the surface of some myeloma cells by flow cytometry, and in one plasmacytoma case by immunohistochemistry. Expression of CT antigens is greater in patients with stage III extramedullary plasmacytoma or high-risk myeloma relative to other cohorts. These data suggest that CT antigens may have important biological implications in malignant gammopathies and that CT-7 may be a suitable target for T cell-based and possibly antibody-mediated immunotherapy of myeloma.

A reversible defect in natural killer T cell function characterizes the progression of premalignant to malignant multiple myeloma.

We studied the function of antitumor T and natural killer T (NKT) cells from the blood and tumor bed in 23 patients with premalignant gammopathy, nonprogressive myeloma, or progressive multiple myeloma. We show that antitumor killer T cells can be detected in patients with both progressive or nonprogressive myeloma. V alpha 24+V beta 11+ invariant NKT cells are detectable in the blood and tumor bed of all cohorts. However, freshly isolated NKT cells from both the blood and tumor bed of patients with progressive disease, but not nonprogressive myeloma or premalignant gammopathy, have a marked deficiency of ligand-dependent interferon-gamma production. This functional defect can be overcome in vitro using dendritic cells pulsed with the NKT ligand, alpha-galactosylceramide (alpha-GalCer). Fresh myeloma cells express CD1d, and can be efficiently killed by autologous NKT cells. We hypothesize that presentation of tumor derived glycolipids by myeloma cells leads to NKT dysfunction in vivo. These data demonstrate that clinical progression in patients with monoclonal gammopathies is associated with an acquired but potentially reversible defect in NKT cell function and support the possibility that these innate lymphocytes play a role in controlling the malignant growth of this incurable B cell tumor in patients.