Erdheim Chester disease in a patient with Burkitt lymphoma: a case report and review of literature

Background

Erdheim Chester disease (ECD) is a rare, non-Langerhans cell histiocytosis characterized by widespread tissue infiltration by CD68-positive, CD1a-negative foamy histiocytes. ECD can be difficult to identify, and diagnosis relies on the presence of histiocytes with certain histologic and immunophenotypic features in an appropriate clinical and radiologic setting. Clinical signs and symptoms are variable depending on which organ systems are involved. Most patients have at least skeletal involvement with bone pain as well as fatigue. Other common manifestations include diabetes insipidus, cardiac, periaortic, or retro-orbital infiltration/fibrosis, kidney impairment, xanthelasmas, among others.

Case presentation

Herein, we describe a case of BRAF-mutation positive ECD in a patient with Burkitt lymphoma, and we review recent literature.

Conclusion

Underlying BRAF and other MAPK pathway mutations are identified in approximately 50% of cases of ECD, which aids in diagnosis as well as enables novel targeted treatments. ECD patients have an increased risk of myeloid neoplasms; however, unlike other histiocytoses, an association with lymphoproliferative disorders has not been recognized.

Histology of colorectal adenocarcinoma with double somatic mismatch-repair mutations is indistinguishable from those caused by Lynch syndrome

Lynch syndrome (LS) is the most common form of hereditary colon cancer. Germline mutations in the mismatch-repair (MMR) genes MLH1, MSH2 (EPCAM), MSH6, and PMS2, followed by a second hit to the remaining allele, lead to cancer development. Universal tumor screening for LS is routinely performed on colon cancer, and screening has identified patients with unexplained MMR deficiency that lack MLH1 methylation and a germline mutation. Tumor sequencing has since identified double somatic (DS) mutations in the MMR gene corresponding with the absent protein in 69% of these patients. We assessed whether histomorphology could distinguish patients with DS mutations from those with LS. Colorectal cancer patients with DS mutations were identified from population-based cohorts from Iceland (2000-2009); Columbus, Ohio (1999-2005); and the state of Ohio (2013-2016). Next-generation sequencing was performed on tumors with unexplained MMR deficiency. Patients with LS from Ohio cohorts were the comparison group. The histologic features associated with MMR deficiency (tumor-infiltrating lymphocytes, Crohn-like reaction, histologic subtype, necrosis) were evaluated. We identified 43 tumors with DS mutations and 48 from patients with LS. There was no significant difference in histologic features between tumors in LS patients and tumors with DS mutations. Because histology of tumors with DS mutations is indistinguishable from those caused by LS, tumor sequencing for evaluation of DS mutations should be considered to help clarify sporadic versus hereditary causes of unexplained MMR deficiency.

Increased Levels of Plasma Epstein Barr Virus DNA Identify a Poor-Risk Subset of Patients With Advanced Stage Cutaneous T-Cell Lymphoma

INTRODUCTION

Outcomes in advanced stage (AS) cutaneous T-cell lymphomas (CTCL) are poor but with great variability. Epstein-Barr virus (EBV) is associated with a subset of non-Hodgkin lymphomas. Frequency of plasma EBV-DNA (pEBVd) detection, concordance with EBV RNA (EBER) in tumor tissue, codetection of plasma cytomegalovirus DNA (pCMVd), and prognostic effect in AS CTCL are unknown.

PATIENTS AND METHODS

Patients (n = 46; 2006-2013) with AS CTCL (≥IIB) were retrospectively studied. pEBVd and pCMVd were longitudinally measured using quantitative real-time polymerase chain reaction. EBER in situ hybridization (ISH) was performed on tumor samples. Survival from time of diagnosis (ToD) and time of progression to AS was assessed.

RESULTS

Plasma EBV-DNA and pCMVd were detected in 37% (17 of 46) and 17% (8 of 46) of AS CTCL patients, respectively. pCMVd detection was significantly more frequent in pEBVd-positive (pEBVd(+)) than pEBVd(-) patients (35% vs. 7%; P = .038). Tumor tissue for EBER-ISH was available in 14 of 17 pEBVd(+) and 22 of 29 pEBVd(-) patients; 12 of 14 (85.7%) pEBVd(+) patients were EBER(+) versus 0 of 22 pEBVd(-) patients. Frequency of large cell transformation (LCT) tended to be greater in pEBVd(+) patients, but was not significant (10 of 14 pEBVd(+) vs. 10 of 23 pEBVd(-); P = .17). No notable differences in rates of increased levels of serum lactate dehydrogenase (LDH) were observed (17 of 17 pEBVd(+) vs. 27 of 29 pEBVd(-)). pEBVd detection was associated with significantly worse survival from ToD (P = .021) and time of progression to AS (P = .0098).

CONCLUSION

Detection of cell-free plasma EBV-DNA was highly concordant with the presence of EBERs in tumor tissue, predicted survival independent of LDH and LCT, and should be further studied as a biomarker in AS CTCL.

Combination therapy with capecitabine and temozolomide in patients with low and high grade neuroendocrine tumors, with an exploratory analysis of O6-methylguanine DNA methyltransferase as a biomarker for response

Recent advances in the treatment of neuroendocrine tumors (NET), including the combination regimen of capecitabine and temozolomide (CAPTEM), have mostly focused on grade 1 and 2 pancreatic neuroendocrine tumors (pNET). We undertook a retrospective review of 38 patients with advanced NET treated with CAPTEM, including patients with non-pancreatic tumors as well as grade 2 and 3 tumors. O⁶-methylguanine DNA methyltransferase (MGMT) expression was assessed as a predictive biomarker. We found that CAPTEM demonstrated activity in patients with all grades and in pNET and non-pNET. Median progression free survival (mPFS) was 13.0 months (95% CI: 5.6-17.0) and median overall survival (mOS) 29.3 months (95% CI 17.7 - 45.3). Among evaluable patients, there were 11 (38%) partial responses, 15 (52%) stable disease, and 3 (10%) progressive disease for a disease control rate of 90%. A higher rate of partial responses occurred in patients whose tumors had low levels of MGMT expression (63%) compared to intermediate-high (17%) (p=0.19). Our results show that CAPTEM therapy is active in patients with NET including in previously treated patients and in those with poorly-differentiated histology. We observed a trend towards increased response rate, median PFS, and median OS in patients whose tumors had low MGMT protein expression.

BRAF V600E expression in histiocytic sarcoma associated with splenic marginal zone lymphoma: a case report

Background

Histiocytic sarcoma is a rare histiocytic neoplasm of unknown etiology that constitutes less than 1% of hematologic malignancies. A few cases of histiocytic sarcoma harboring the BRAF^V600E mutation have been reported, but this finding has not been confirmed in all studies.

Case presentation

We report the case of a 63-year-old white woman with a history of splenic marginal zone lymphoma who presented with 2 weeks of right-sided neck swelling. Positron emission tomography revealed an intensely hypermetabolic and destructive soft tissue mass in her right skull base. A bone marrow biopsy was performed, which revealed an infiltrate of malignant cells characterized as large pleomorphic cells with frequent folded/irregular nuclei, variably prominent nucleoli, fine chromatin, and abundant amounts of eosinophilic cytoplasm. The malignant cells were positive for CD163, CD68 (granular), lysozyme (granular), CD4, and CD45 (partial). Based on the biopsy findings, she was diagnosed as having histiocytic sarcoma. The malignant cells tested positive for the BRAF^V600E protein using immunohistochemistry. Before treatment of her histiocytic sarcoma could be initiated, she developed disseminated intravascular coagulation and acute hypoxemic respiratory failure secondary to non-cardiogenic pulmonary edema. She decided to pursue comfort care and died in our hospital 2 weeks following admission.

Conclusions

Our case illustrates the aggressive nature of histiocytic sarcoma, and provides rare evidence that histiocytic sarcoma associated with indolent lymphomas may harbor the BRAF^V600E mutation. Further research is needed to clarify the role of targeted therapies such as vemurafenib in the treatment of patients with this disorder.

Complete response to induction therapy in patients with Myc-positive and double-hit non-Hodgkin lymphoma is associated with prolonged progression-free survival

BACKGROUND

Myc-positive B-cell non-Hodgkin lymphoma (NHL) with or without a B-cell chronic lymphocytic leukemia/lymphoma 2 (BCL2) rearrangement is associated with inferior progression-free survival (PFS) and overall survival (OS). In this study, the authors reviewed the outcomes of patients with myc-positive and double-hit NHL at The Ohio State University.

METHODS

All patients who had non-Burkitt, aggressive B-cell NHL from 2008 to 2011 were assessed for the t(14;18) translocation and for v-myc avian myelocytomatosis viral oncogene homolog (CMYC) rearrangements at diagnosis, and all myc-positive patients were included in the current analysis. Associations with clinical characteristics were described, and univariable and multivariable models were used to assess correlations between clinical variables and outcomes.

RESULTS

Of 49 myc-positive patients, 29 patients also had BCL2 rearrangements (double-hit NHL). No patients underwent autologous stem cell transplantation in first remission. For all myc-positive patients, the median PFS was 16.6 months, and the median OS was 37.7 months. For patients who had double-hit NHL, the median PFS was 8 months, and the median OS was 12.5 months; whereas the median PFS and OS were not reached for myc-positive patients. A complete response (CR) after front-line therapy, the presence of t(14;18), International Prognostic Index (IPI) group, and age were associated with PFS; whereas only the achievement of a CR and age >60 years were associated with OS in the multivariable setting. The median PFS was 3.3 months, and the median and OS was 7.0 months for patients who did not attain a CR; and the medians were not reached for patients who achieved a CR (P < .00001).

CONCLUSIONS

The achievement of a CR with front-line therapy is associated with a prolonged PFS and OS in patients with myc-positive NHL, even after adjusting for type of initial therapy, histology, age, IPI, or the presence of a concurrent BCL2 translocation.

NY-ESO-1 is a sensitive and specific immunohistochemical marker for myxoid and round cell liposarcomas among related mesenchymal myxoid neoplasms

Myxoid and round cell liposarcomas constitute approximately one-third of all liposarcomas, a relatively common group of fat-derived soft tissue sarcomas. The histomorphology is a continuum between highly differentiated myxoid and poorly differentiated round cell components. The gold standard of diagnosis is dependent on histomorphology and/or identification of t(12;16)(q13;p11) translocation by cytogenetics or demonstration of DDIT3 rearrangements by fluorescence in situ hybridization. There are currently no diagnostic immunohistochemical stains available. The broad range of myxoid neoplasms in the differential diagnosis includes a variety of sarcomas. Given the notable differences in disease biology among myxoid neoplasms, which range from benign to aggressive, an accurate diagnosis is imperative for proper treatment and prognostication. Prompted by our recent study showing frequent expression of the cancer testis antigen NY-ESO-1 in myxoid and round cell liposarcomas, we sought to evaluate the utility of NY-ESO-1 as an immunohistochemical marker for myxoid and round cell liposarcoma among mesenchymal myxoid neoplasms within the differential diagnosis. Formalin-fixed, paraffin-embedded blocks were obtained for the following mesenchymal myxoid neoplasms (n=138): myxoid and round cell liposarcoma (n=38); well-differentiated liposarcoma (n=12); lipoma (n=20; 4 with myxoid change); extra-cardiac soft tissue myxoma (n=39); extraskeletal myxoid chondrosarcoma (n=12); myxofibrosarcoma (n=10: 5 low grade, 2 intermediate grade, 3 high grade); and low-grade fibromyxoid sarcoma (n=7). Utilizing standard immunohistochemistry protocols, full sections were stained with NY-ESO-1 (clone E978), and staining was assessed for intensity (1-2+), percentage of tumor positivity, and location. In all, 36/38 (95%) of the myxoid and round cell liposarcomas demonstrated NY-ESO-1 immunoreactivity. The majority of the positive cases (34/36; 94%) showed strong, homogenous staining (>50% tumor positivity), and two cases (6%) showed weak (1+ intensity), patchy staining (20-30% tumor positivity). Immunoreactivity was predominantly cytoplasmic. All the other neoplasms evaluated were negative for NY-ESO-1. NY-ESO-1 appears to be a sensitive and a specific marker for myxoid and round cell liposarcoma among mesenchymal myxoid neoplasms. The assessment of NY-ESO-1 expression by immunohistochemistry in the appropriate setting provides a cheaper, faster, and more accessible confirmatory test.