Xiong Zeng Zhu

Cutaneous Rosai-Dorfman disease: A clinical and histopathologic study of 25 cases in China

Cutaneous Rosai-Dorfman disease (CRDD) is a rare proliferative disorder of histiocytes with unknown etiology, broadly different from systemic Rosai-Dorfman disease. We present the largest series of CRDD, describing the clinical manifestation, histopathology, immunohistochemistry, and follow-up course of 25 cases in China. Clinically, 39 skin lesions in 25 patients were divided into 3 main types: papulonodular type (79.5%), indurated plaque type (12.8%), and tumor type (7.7%). Extremities were the most frequently involved, followed by trunk and face. None of the patients was found to have visceral organ involvement or lymphadenopathy. Microscopically, CRDD was characterized by scattering, clusters or sheets of large polygonal histiocytes intermingled with a florid, mixed inflammatory infiltrate. The most important feature was emperipolesis, which can be highlighted by S-100 protein stain. Patch and bandlike infiltrate of numerous mature plasma cells around glands and vessels was a constant finding in all lesions. Neutrophils existed in all cases to a variable degree with 2 cases forming microabscess. Four cases were remarkable for fibrosis, and xanthomatous change was observed in 2 cases. Coexistence of localized Langerhans cell histiocytosis and CRDD was interestingly found in case 7, which was evidenced by CD1a stain. Clinical follow-up in 22 patients, ranging from 2 to 55 months, indicated that surgical excision was the exclusive effective treatment for CRDD. Partial or complete spontaneous remission was achieved in 7 patients within 6 to 55 months. Owing to its favorable outcome, CRDD should be differentiated from a variety of benign and malignant lesions. Recognition of its wide clinical spectrum and histologic features combined with S-100 protein stain can help to establish the correct diagnosis.

Expression of follicular helper T cell markers in nodal peripheral T cell lymphomas: a tissue microarray analysis of 162 cases

Aims To evaluate the role of the follicular helper T (TFH) cell markers, CD10, BCL6, programmed death-1 (PD-1) and CXCL13, in the differential diagnosis of nodal peripheral T cell lymphomas (PTCLs) and to determine whether PTCL subtypes other than angioimmunoblastic T cell lymphoma (AITL) express TFH cell markers. Methods 162 nodal PTCL specimens and 53 other lymphoid pathology specimens were collected. Immunohistochemistry for CD10, BCL6, PD-1 and CXCL13 was performed on tissue microarray sections. Morphological feature analysis and double labelling assay were also performed. Results For AITL cases, the rate of CD10, BCL6, PD-1 and CXCL13 expression was 75.0% (36/48), 66.7% (32/48), 93.8% (45/48) and 97.9% (47/48), respectively. Expression of CD10, PD-1 and CXCL13 in the AITL group was significantly higher than in other nodal PTCLs and the control group (p<0.05). The rate of coexpression of three or four (≥3) markers was 83.3% for AITL cases, which was significantly higher than that for any of the non-AITL cases (0–4.9%; p<0.05). The rate of coexpression of PD-1 and CXCL13 (91.7%, 44/48) was significantly higher than that of CD10 and BCL6 (56.3%, 27/48) (p=0.000) in the AITL group. Seventeen cases of PTCL not otherwise specified (PTCL, NOS) expressed CXCL13, including both cases of the follicular variant of PTCL, NOS (FVPTCL, NOS), three of the four cases of the lymphoepithelioid variant of PTCL, NOS (LVPTCL, NOS), and the remaining 12 cases which displayed one or more features of AITL. Conclusions The combined detection of CD10, BCL6, PD-1 and CXCL13 has high specificity and sensitivity for the differential diagnosis of AITL. PD-1 and CXCL13 are more sensitive, superior diagnostic markers for AITL than CD10 and BCL6. Currently, TFH cell markers are the only available markers that show high specificity for AITL. LVPTCL, NOS and/or FVPTCL, NOS may also arise from TFH cells and fall within the spectrum of AITL.

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.